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Zemanchik, Normand Joseph. "Preferred building orientation for naturally ventilated buildings." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60641.
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Determining optimum building orientation for naturally ventilated buildings is an important concept. Obtaining the optimum orientation will determine the success of the performance of a naturally ventilated building.This project deals with obtaining the preferred building orientation for 10 regional weather stations across the province of Ontario. Different methods were utilized to obtain the preferred building orientation: the average ventilation rate method, the percentage of ventilation rates above and below the minimum summer ventilation rates, and the consecutive hours method, ie. the number of weather events that are below the minimum summer design ventilation rate for a specific building configuration. The analysis involves six building orientations (0$ sp circ$, 30$ sp circ$, 60$ sp circ$, 90$ sp circ$, 120$ sp circ$, and 150$ sp circ$) with respect to North, and exterior temperatures greater than or equal to 20$ sp circ$C, 25$ sp circ$C, or 30$ sp circ$C.
Optimizing building orientation, to minimize the number of weather events where the ventilation rates are below the summer design ventilation rate is the general goal of this research work.
A statistical analysis was carried out based on the results obtained from the data for the frequency of ventilation rates versus the ventilation rates below the summer design ventilation rate, for all 10 Ontario weather stations, for temperatures greater than or equal to 20$ sp circ$C, and all six building orientations. The output of the statistical analysis showed that for the above mentioned temperature range, that there is a relationship between the ventilation rates below the design summer ventilation rate and building orientation.
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Chen, Shaw-Bing. "Natural ventilation generates building form." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/65048.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1996.Includes bibliographical references (leaves 149-151).
Natural ventilation is an efficient design strategy for thermal comfort in hot and humid climates. The building forms can generate different pressures and temperatures to induce natural ventilation. This thesis develops a methodology that uses a computational fluid dynamics (CFD) program. The purpose of the CFD program is to assist architects to design optimum building form for natural ventilation. The design of a cottage in Miami, Florida demonstrates the application of this methodology. The first phase of this methodology is to create an input file for the CFD program. The input file uses wind velocity, wind direction, and air temperature of the site to simulate the weather. Different weather conditions can be generated through modification of the first input file. The second phase of this methodology is to develop building forms. The CFD programs can simulate airflow in different building forms by changing the building geometry in the input files. The program calculates the airflow pattern, velocity, and temperature for different forms. The printouts of the simulations allow architects to understand the airflow behavior in spaces with different forms. This thesis also uses the CFD program to study variance between the proposed and the actual results of a design. As demonstrated in a sports museum in Washington, DC, this case study clearly displays a difference between the intentions of the architect and the results of CFD calculation. Some problems appear in developing CFD models. However, when the input files are correctly defined, and the calculations converge, very few computational problems appear in developing building forms. Therefore, architects can easily use the CFD programs to develop building form after the input files are correctly defined.
by Shaw-Bing Chen.
M.S.
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Dong, Bing. "Integrated Building Heating, Cooling and Ventilation Control." Research Showcase @ CMU, 2010. http://repository.cmu.edu/dissertations/4.
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Current research studies show that building heating, cooling and ventilation energy consumption account for nearly 40% of the total building energy use in the U.S. The potential for saving energy through building control systems varies from 5% to 20% based on recent market surveys. In addition, building control affects environmental performances such as thermal, visual, air quality, etc., and occupancy such as working productivity and comfort. Building control has been proven to be important both in design and operation stages.
Building control design and operation need consistent and reliable static and dynamic information from multiple resources. Static information includes building geometry, construction and HVAC equipment. Dynamic information includes zone environmental performance, occupancy and outside weather information during operation.. At the same time, model-based predicted control can help to optimize energy use while maintaining indoor set-point temperature when occupied. Unfortunately, several issues in the current approach of building control design and operation impede achieving this goal. These issues include: a) dynamic information data such as real-time on-site weather (e.g., temperature, wind speed and solar radiation) and occupancy (number of occupants and occupancy duration in the space) are not readily available; b) a comprehensive building energy model is not fully integrated into advanced control for accuracy and robustness; c) real-time implementation of indoor air temperature control are rare. This dissertation aims to investigate and solve these issues based on an integrated building control approach.
This dissertation introduces and illustrates a method for integrated building heating, cooling and ventilation control to reduce energy consumption and maintain indoor temperature set-point, based on the prediction of occupant behavior patterns and weather conditions. Advanced machine learning methods including Adaptive Gaussian Process, Hidden Markov Model, Episode Discovery and Semi-Markov Model are modified and implemented into this dissertation. A nonlinear Model Predictive Control (NMPC) is designed and implemented in real-time based on Dynamic Programming. The experiment test-bed is setup in the Solar Decathlon House (2005), with over 100 sensor points measuring indoor environmental parameters such as temperature, relative humidity, CO2, lighting, motion and acoustics, and power consumption for electrical plugs, HVAC and lighting. The outdoor environmental parameters, such as temperature, relative humidity, CO2, global horizontal solar radiation and wind speed, are measured by the on-site weather station. The designed controller is implemented through LabVIEW.
The experiments are carried out for two continuous months in the heating season and for a week in cooling season. The results show that there is a 26% measured energy reduction in the heating season compared with the scheduled temperature set-points, and 17.8% energy reduction in the cooling season. Further simulation-based results show that with tighter building façade, the cooling energy reduction could reach 20%. Overall, the heating, cooling and ventilation energy reduction could reach nearly 50% based on this integrated control approach for the entire heating/cooling testing periods compared to the conventional scheduled temperature set-point.
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Ali, Sadaqat, and Possavee Thummakul. "Mapping and analyzing Ventilation system in University building." Thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-12397.
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This Master Studies Thesis of Quality in Process Technology deals with Process Improvement. The ventilation system of University building is dealt as a Process and is looked for improvements. The ventialtion system for two computer rooms is studied and analyzed for the variaitons in the operating conditions.
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Bergman, Erik. "Evaluation of ventilation for an office building : Situated in Gävle, Sweden." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-17274.
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Since the CO 2-emissions and electricity prices are ever increasing many companies have tried to reduce their energy consumption in order to reduce both CO2-emissions and the cost of using energy. Therefore, in this article an office building situated in Sweden have been investigated with its current ventilation flow and what saving poten-tials can be made from heat recovery and a different ventilation flow in regards to health, energy and cost. Empirical data have been collected to be able to calculate ener-gy savings made by heat recovery and new ventilation flow. A ventilation flow of 25 l/s per office were chosen and that the conference room should have at least 3 l/s per m² the dining room and locker was not investigated thoroughly and therefore a ventilation flow from the recommendations of Sweden was followed. The total flows became, 530 l/s respectively 630 l/s for the top and bottom floor. A rotating heat exchanger with an es-timated efficiency of 80% was used for heat recovery and through the two methods combined an energy reduction up to 96,4 % for heating and 83,4 % from the electricity could be reduced.
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Tsui, Ka-cheung, and 徐家祥. "Neighborhood ventilation of a building cluster by combined forces." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B42182128.
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Hughes, Ben Richard. "Performance investigation of a naturally driven building ventilation terminal." Thesis, Sheffield Hallam University, 2009. http://shura.shu.ac.uk/19845/.
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Naturally driven ventilation terminals (wind vents) offer a way of improving comfort conditions while reducing building carbon emissions. The device sits on top of the building, trapping the air at higher velocity and delivering it into the interior of the building. The current cross-ventilated design combines the velocity, pressure, and density of air to produce wind driven ventilation. Currently there is scarce research investigating the performance of these devices in the United Kingdom (UK).This thesis provides a performance evaluation and optimisation of a commercially available building ventilation terminal (a benchmark) in the UK. A systematic review and optimisation of the device's geometrical components has been carried out using Computational Fluid Dynamics (CFD) and far-field experimentation. An extensive literature review was carried out to provide the framework for this investigation. Building on existing (developed) research techniques, the knowledge gaps identified in this subject area, were isolated and examined thoroughly. A new methodology for creating and dynamically modifying CFD models using complete wind vent geometry was devised. Using this technique the wind vent was subjected to systematic geometrical variation to establish the contribution of each component to the overall performance of the device. The research used full scale Far field experimentation to validate the CFD models of the wind vent. The Far field experimentation provided greater accuracy (0 - 0.08m/s) for this application, when compared to other validation techniques such as wind tunnel experimentation (0 - 0.15m/s). A new empirical methodology was devised for predicting the airflow through a wind vent. The empirical method was based on two dimensionless coefficients (0.44 and 0.3) found through the CFD experimentation research carried out. The investigation established the device is capable of meeting current British Standards Institute (BSI) guidelines, and is therefore suitable for UK applications. The BSI recommended 0.8L/sec of fresh air per m[2] floor area. The benchmark wind vent geometry delivered 1.1 L/sec per m[2] of floor area with an external wind speed of 1m/s (UK average was 4.5m/s). The key geometrical components (in isolation) were identified as the louver angle, distance between louvers and the number of louvers (now subject to patent number 0809311.4). Each of these geometrical variations provided an increase in performance over the benchmark case in the range of 27-45%. An optimum configuration of these parameters did not deliver the same increased performance range as the isolated case. However the optimised combination case increased the internal air movement rate using 50% less material than that of the benchmark geometry.
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Khatami, Narguess. "Retrofitted natural ventilation systems for a lightweight office building." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/17820.
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This study aimed to develop retrofitted natural ventilation options and control strategies for existing office buildings to improve thermal comfort, indoor air quality and energy consumption. For this purpose, a typical office building was selected in order to identify opportunities and constraints when implementing such strategies. Actual performance of the case study building was evaluated by conducting quantitative and qualitative field measurements including physical measurements and questionnaire surveys. Based on the actual building performance, a combination of Dynamic Thermal Simulation (using IES) and Computational Fluid Dynamics (using PHOENICS) models were built to develop appropriate natural ventilation options and control strategies to find a balance between energy consumption, indoor air quality, and thermal comfort. Several retrofitted options and control strategies were proposed and the best retrofitted natural ventilation options and control strategies were installed in the case study building. Post occupancy evaluation of the case study building after the interventions was also carried out by conducting physical measurements and questionnaire surveys. Post refurbishment measurements revealed that energy consumption and risk of overheating in the refurbished building were reduced by 9% and 80% respectively. The risk of unacceptable indoor air quality was also reduced by 60% in densely occupied zones of the building. The results of questionnaire surveys also revealed that the percentage of dissatisfied occupants reduced by 80% after intervention. Two new products including a Motorized ceiling tile and NVlogIQ , a natural ventilation wall controller, were also developed based on the results of this study.
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Tsui, Ka-cheung. "Neighborhood ventilation of a building cluster by combined forces." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B42182128.
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Afroz, Zakia. "Performance improvement of building heating, cooling and ventilation systems." Thesis, Afroz, Zakia (2019) Performance improvement of building heating, cooling and ventilation systems. PhD thesis, Murdoch University, 2019. https://researchrepository.murdoch.edu.au/id/eprint/54931/.
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Heating, Ventilation, and Air Conditioning (HVAC) systems are responsible for a substantial share of the energy consumed in commercial buildings. Energy used by HVAC systems has increased over the years due to its broader application in response to the growing demand for better thermal comfort within the built environment. While existing case studies demonstrate the energy saving potential of efficient HVAC operation, there is a lack of studies quantifying energy savings from optimal operation of HVAC systems when considering indoor environmental conditions. This research aims to improve the performance of HVAC systems by optimizing its energy consumption without compromising indoor environmental conditions.
The concept of maintaining indoor environmental conditions poses new challenges to the optimal operation of HVAC systems. While the primary objective of ensuring optimal operation is to minimize energy consumption, controlling the indoor environmental parameters, e.g., temperature, humidity, the level of carbon dioxide (CO2), and volatile organic compounds (VOCs) to remain within the acceptable range imposes excess energy use. These two conflicting objectives constitute a multi-variable constrained optimization problem that has been solved using a particle swarm algorithm (PSO).
A real-time predictive model has been developed for individual indoor environmental parameters and HVAC energy consumption using Nonlinear Autoregressive Exogenous (NARX) neural network (NN). During model development, efforts have been paid to optimize the performance of the model in terms of complexity, prediction results, and ease of application to a real system. The proposed predictive models are then optimized to provide an optimal control setting for HVAC systems taking into account seasonal variations. An extensive case study analysis has been performed in a real commercial building to demonstrate the effectiveness of developing predictive models and evaluating the relevance of integrating indoor air quality (IAQ) within the optimization problem.
Results show that it is possible to minimize 7.8% energy consumption from HVAC systems without compromising indoor environmental conditions. This study demonstrates that the proposed optimal control settings maintain the indoor environment within the acceptable limit of thermal comfort conditions (indoor air temperature between 19.60 to 28.20C and indoor air humidity between 30 to 65 %RH as per ASHRAE Standard 55-2017) and air quality (CO2 ≤ 800 ppm and VOC ≤ 1000ppm as per Australian Standard AS 1668.2 2016). The outcomes of this research will act as a guideline for energy management practices, not only for energy efficient building design and retrofitting but also for building energy performance analysis. This research provides insight into the aspects that affect the performance of predictive models for indoor temperature. The proposed feature selection approach establishes its efficacy to determine salient and independent input parameters without compromising prediction performance. The application of this approach will minimize the measurement and data storing cost of variables. Further, using fewer numbers of input parameters in the model will reduce the computational cost and time. Thus, the proposed model establishes its applicability in a real system for a more extended period of advanced prediction. In addition, the need to better account for building-occupant interactions as an important step to maintain a healthy indoor environment has been recognized through evaluating a real-life demand control (DCV) system. Lastly, the proposed optimization approach, where four defined environmental parameters are considered simultaneously presents a new outlook within the HVAC control system by eliminating the unseen interface between thermal comfort and IAQ.
Overall, this unexploited potential to simultaneously improve the performance of HVAC systems and indoor environmental conditions drives the discussion on reconsidering the set-point configuration standards of HVAC in commercial buildings, either as part of individual building retrofit planning or as part of building regulatory applications.
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Pálsson, Daði Snær. "Hybrid Ventilation : Simulation of Natural Airflow in a Hybrid Ventilation System." Thesis, KTH, Installations- och energisystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-146761.
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This thesis investigates the possibilities of using hybrid ventilation in an office building in Stockholm. The focus is on simulating the natural airflow to find out for which conditions it is sufficient. The thesis is done at White Arkitekter AB in cooperation and under the supervision of environmental specialists working there. A literature study is carried out to study what has been done before in Sweden as well as in other countries. Computer simulations are used to simulate the airflow to examine the conditions and architecture. A synthetic computer model representing a realistic office building is built up as a starting point. The ventilation method for the natural ventilation part is to take air in through the fa\c{c}ade and use the stack effects in an atrium for natural ventilation. By altering the architecture and the sizes of the openings according to the results from the simulations the building is dimensioned and formed to cope with the rules and requirements about the indoor air quality in workplaces. The simulations are done with a multi zone energy performance simulation tool that can simulate airflows and indoor air climate conditions in the zones as well as the energy consumption. Computational fluid dynamics calculations are then used to more closely simulate the conditions within the zones. The results from those simulations suggest that the natural ventilation as a part of a hybrid ventilation works for all the floors of the building for up to 10$\,^{\circ}\mathrm{C}$. The computational fluid dynamics simulations showed that the thermal comfort of all the occupants is fulfilled for these conditions but there is a risk of occupants experiencing draught because of to high velocities in the air especially for the colder outdoor temperatures. For the higher outdoor temperatures the airflow needs to be enforced to ensure sufficient conditions for the occupants and for the colder temperatures mechanical ventilation is needed to decrease heat losses and avoid the risk of draught.
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Spentzou, Eftychia. "Refurbishment of apartment buildings in the Mediterranean Region for natural ventilation : implications for building design." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/18592.
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With the emergence of climate change, the increasing figure of energy consumption for cooling in buildings expresses an urgent need for energy conscious design of new and existing buildings, and there is a significant opportunity for implementation of natural ventilation strategies. The high-energy consumption of the Greek domestic sector, the number of existing multi-storey apartment buildings, the small rate of building retrofitting in Greece and the warm, dry climate of Greece, indicate the potential to achieve significant energy reductions for cooling via natural ventilation. The aim of this research was to evaluate the energy saving potential of natural ventilation solutions for domestic buildings in the Mediterranean climate to deliver summer comfort, and to propose a low-energy refurbishment design guide. The natural ventilation efficiency of an urban multi-storey apartment building in Athens and the potential implementation of advanced natural ventilation strategies, were evaluated using modelling tools. This would provide the knowledge for future energy refurbishments. The building was a representative example of over 4 million buildings in Greece. Several ventilation strategies were implemented in a single apartment (51.4m2) and evaluated in order to enhance the existing single-sided ventilation strategy of the building, including: daytime and nighttime ventilation; cross ventilation strategies; use of a wind-catcher; lightweight dynamic façade with shading system; new internal openings; and passive downdraught evaporative cooling strategies. The ventilation performance of the strategies was investigated over the full cooling period using DTM simulations. Controlled natural ventilation strategies, in response to internal and external air properties, delivered: occupants comfort; ventilation rates increase; and reductions in air temperatures and in CO2 levels. Natural day and night ventilation contributed to significant temperature reductions (up to 7°C) relative to the base-case ventilation strategy. The proposed strategies marginally reduced the hours during the cooling period for which the CO2 levels exceeded the upper acceptable limit for comfort. The strategies also achieved air change rates above the minimum acceptable values for comfort were provided; and therefore occupants comfort was achieved. De-coupled internal-external steady state CFD airflow simulations were performed to predict wind pressures across the building openings, and to predict detailed ventilation rates for a number of climate scenarios. Using CFD it was possible to overcome the limitation of DTM and predict average pressures at the location of the openings, considering the location of the building within its surroundings (both external and internal flow simulations were performed), leading to accurate results. It was predicted that the ventilation performance of the wind catcher was significant relative to the simple single or cross-ventilation strategies. The downdraft evaporative cooling performed best at low ventilation rates providing up to 4°C further temperature reductions. Indoor comfort was provided during windless hours for specific strategies (buoyancy driven); this is significant considering that low wind speeds (below 1m/s) were predicted for 14% of the cooling period. The performance of the strategies varies considerably with regard to both wind speed and direction; these should be considered when retrofitting natural ventilation strategies in existing buildings. The proposed strategies delivered natural cooling and adequate ventilation rates, relative the base-case strategy. The combined wind catcher and dynamic façade strategy performed the best; this combined strategy would be recommended for the Mediterranean sub-climate, and for buildings comparable to the type studied. This should be combined with evaporative cooling strategies particularly during windless hours, and mechanical cooling only when these strategies do not provide sufficient performance. For both the CFD and DTM results, empirical relationships were established with statistical methods between indoor air properties and climate characteristics, which can be used to predict behaviours under conditions that have not been examined using simulations. This assists extrapolation of patterns in ventilation performance, to facilitate design guidance of the natural ventilation strategies for implementation in similar buildings. The established performance of the natural ventilation strategies in the case study building assisted the development of a prototype scenario for similar building designs with comparable climatic context. A low-energy refurbishment design guide for natural ventilation was proposed that provides guidelines and design recommendations. Retrofitting such natural ventilation strategies in existing apartment buildings in similar climates presents a significant opportunity to achieve significant energy consumption reductions.
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Green, N. E. "Investigations into the impact of traffic pollution on building ventilation." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311922.
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Frank, Daria. "Effects of turbulence on the ventilation rates through building openings." Thesis, University of Cambridge, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709516.
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Nourozi, Behrouz. "Sustainable building ventilation solutions with heat recovery from waste heat." Licentiate thesis, KTH, Hållbara byggnader, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-256567.
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The energy used by building sector accounts for approximately 40% of the total energy usage. In residential buildings, 30-60% of this energy is used for space heating which is mainly wasted by transmission heat losses. A share of 20-30% is lost by the discarded residential wastewater and the rest is devoted to ventilation heat loss. The main objective of this work was to evaluate the thermal potential of residential wastewater for improving the performance of mechanical ventilation with heat recovery (MVHR) systems during the coldest periods of year. The recovered heat from wastewater was used to preheat the incoming cold outdoor air to the MVHR in order to avoid frost formation on the heat exchanger surface. Dynamic simulations using TRNSYS were used to evaluate the performance of the suggested air preheating systems as well as the impact of air preheating on the entire system. Temperature control systems were suggested based on the identified frost thresholds in order to optimally use the limited thermal capacity of wastewater and maintain high temperature efficiency of MVHR. Two configurations of air preheating systems with temperature stratified and unstratified tanks were designed and compared. A life cycle cost analysis further investigated the cost effectiveness of the studied systems. The results obtained by this research work indicated that residential wastewater had the sufficient thermal potential to reduce the defrosting need of MVHR systems (equipped with a plate heat exchanger) in central Swedish cities to 25%. For colder regions in northern Sweden, the defrosting time was decreased by 50%. The temperature control systems could assure MVHR temperature efficiencies of more than 80% for most of the heating season while frosting period was minimized. LCC analysis revealed that wastewater air preheating systems equipped with temperature stratified and unstratified storage tanks could pay off their costs in 17 and 8 years, respectively.QC 20190830
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Yam, Chi-wai, and 任志偉. "Effect of internal thermal mass on building thermal performance." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B27770631.
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Lysén, Julia, and Evelina Lann. "Energieffektivisering av skolbyggnader geom behovsstyrd ventilation." Thesis, Linnéuniversitetet, Institutionen för teknik, TEK, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-12084.
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Ugursal, Ahmet. "Integration Of Natural Ventilation To Office Building Typology In The Ankara Context: A Case Study." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1042720/index.pdf.
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Together with a global concern for the reduction and conservation of energy, the oil crisis of 1973 brought about a turning point in the design of buildings. Responses in this vein were mostly concentrated on the simplistic one of sealing the building against outdoor conditions. This approach towards energy consumption, associated with the introduction of air-conditioning systems, led to different problems such as Sick Building Syndrome. Lack of user satisfaction also appeared to be a common complaint in such sealed, air-conditioned buildings, leading to a marked drop in employee efficiency and, hence, return on capital investments.
In this study, Emek iShani, a sealed office building located in Ankara, whose curtain wall system was renovated in 2001, was investigated in terms of its natural ventilation potential under two sub-topics. With a survey conducted, user perception towards environmental conditions, and health problems they suffered were investigated. With a computer simulation, natural ventilation potential of the building in terms of energy consumption was examined.
It was resulted from the survey that building occupants have serious health problems. They are also not satisfied with the way the ventilation system functions and most of the occupants liked to have a window opening to outside in order to adjust the inner conditions. It was resulted from the computer simulation that integration of natural ventilation did not make any significant difference in the annual energy consumption of the building. On the other hand, cooling loads of the building were eliminated in summer months. As a result, introduction of natural ventilation appeared to be an appropriate tool for more user satisfaction and energy conservation.
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Jones, Benjamin Michael. "Quantifying the performance of natural ventilation windcatchers." Thesis, Brunel University, 2010. http://bura.brunel.ac.uk/handle/2438/4713.
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The significant energy consumption of non- domestic buildings has led to renewed interest in natural ventilation strategies that utilise the action of the wind, and the buoyancy of hot air. One natural ventilation element is the Windcatcher, a roof mounted device that works by channelling air into a room under the action of wind pressure, whilst simultaneously drawing air out of the room by virtue of a low pressure region created downstream of the element. A significant number of Windcatchers are fitted in UK schools where good indoor air quality is essential for the health and performance of children. The performance of a ventilation system in a school classroom is determined by its ability to provide ventilation in accordance with UK government ventilation, air quality, and acoustic requirements. However, there is only limited performance data available for a Windcatcher, particularly when operating in-situ. Accordingly, this thesis investigates the performance of a Windcatcher in three ways: First, a semi-empirical model is developed that combines an envelope flow model with existing experimental data. Second, measurements of air temperature, relative humidity, carbon dioxide, and noise levels in school classrooms are assessed over summer and winter months and the results compared against UK Government requirements. Finally, air flow rates are measured in twenty four classrooms and compared against the semi-empirical predictions. The monitoring reveals that air quality in classrooms ventilated by a Windcatcher has the potential to be better than that reported for conventional natural ventilation strategies such as windows. Furthermore, an autonomous Windcatcher is shown to deliver the minimum ventilation rates specified by the UK Government, and when combined with open windows a Windcatcher is also capable of providing the required mean and purge ventilation rates. These findings are then used to develop an algorithm that will size a Windcatcher for a particular application, as well as helping to improve the ventilation strategy for a building that employs a Windcatcher.
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Filsell, Steven. "Investigations of positive air pressure transients in building drainage ventilation systems." Thesis, Heriot-Watt University, 2006. http://hdl.handle.net/10399/123.
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Swiegers, Jacobus Johannes. "Inlet and outlet shape design of natural circulation building ventilation systems." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97110.
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Thesis (MEng)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Increased awareness of environmental problems has awakened interest in renewable energy systems. Natural ventilation systems are especially of interest, as people spend most of their time indoors. Indoor air quality is an important consideration when human health and occupant comfort is to be maintained. This study focusses on determining the best inlet and outlet shape for a natural ventilation system from a chosen set of configurations. The inlet and outlet configurations were tested on a PDEC (Passive Downdraught Evaporative Cooling) shaft and solar chimney. The PDEC incorporated an evaporative cartridge made from cotton cloth. Independent models of the PDEC and solar chimney were built in a thermally controlled space where the configurations were tested at different wind speeds. The configurations were tested on a wet or dry PDEC shaft and on a hot or cold solar chimney. One-dimensional finite difference models, accounting for some two-dimensional effects in the evaporative cartridge, of the cartridge and solar chimney were developed. CFD (Computational Fluid Dynamics) models were further constructed in FLUENTr, simulating operating conditions for each inlet and outlet test. The CFD models were constructed to obtain numerical comparisons for the experimental data. The ability of the one-dimensional and CFD models to predict the performance of the PDEC and solar chimney were investigated. The results indicated that an inlet configuration called a TFI (Turbine Fan Inlet) performed the best at the tested wind speeds. The TFI was further able to significantly increase volumetric flow rate in the PDEC shaft for the dry evaporative cartridge tests. The outlet that performed best under the tests is a Windmaster Tornado Wind Turbine, or Whirlybird, which is a commercially available configuration. The one-dimensional models were not able to accurately predict conditions during start-up. The CFD models were highly accurate in predicting the experimental values. It is recommended that a two-dimensional theoretical model be developed to better predict start-up conditions.
AFRIKAANSE OPSOMMING: Verhoogde bewustheid van omgewings probleme het belangstelling in hernubare energie stelsels ontwaak. Natuurlike ventilasie stelsels is veral van belang, sedert mense die meeste van hul tyd binnenshuis spandeer. Binnenshuise lug kwaliteit is ’n belangrike oorweging wanneer menslike gesondheid en insittendes se gemak in stand gehou moet word. Hierdie studie fokus op die bepaling van die beste inlaat en uitlaat vorm van ’n gekose stel konfigurasies vir ’n natuurlike ventilasie-stelsel. Die inlaaten uitlaat-konfigurasies is op ’n PDEC (Passive Downdraught Evaporative Cooling) skag en sonkrag skoorsteen getoets. Die PDEC het ’n verdampings doek, gemaak van katoen, ingesluit. Onafhanklike modelle van die PDEC en sonkrag skoorsteen is in ’n termies-beheerde ruimte en die konfigurasies is by ’n onveranderende wind spoed getoets. Die konfigurasies is op ’n nat of droog PDEC skag en op ’n warm of koue son skoorsteen getoets. Een-dimensionele eindige verskil modelle, wat sommige twee-dimensionele effekte in ag neem in die verdampings doek, van die doek en sonkrag skoorsteen is ontwikkel. CFD (Computational Fluid Dynamics) modelle is verder gebou in FLUENTr, wat die werkstoestande vir elke inlaat en uitlaat toets simuleer. Die CFD modelle is ontwikkel om die eksperimentele data met numeriese waardes te vergelyk. Die vermoë van die een-dimensionele en CFD modelle om die verrigting van die PDEC en sonkrag skoorsteen te voorspel, is ondersoek. Die resultate dui daarop dat ’n inlaat opset genoem TFI (Turbine Fan Inlet) die beste vaar by die elke getoetsde wind spoed. Die TFI was verder in staat om die volumetriese vloeitempo in die PDEC skag aansienlik te verhoog vir die toetse met ’n droë verdamping doek. Die uitlaat wat die beste presteer het in die toetse is ’n Windmaster Tornado Wind Turbine, of Whirlybird, wat ’n kommersieel beskikbare konfigurasie is. Die een-dimensionele modelle was nie in staat om die toestande tydens die begin-fase akkuraat te voorspel nie. Die CFD modelle was hoogs akkuraat in die voorspelling van die eksperimentele waardes. Dit word aanbeveel dat ’n twee-dimensionele teoretiese model ontwikkel word om die toestande tydens begin-fase beter te voorspel.
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Bakhtiari, Hossein. "Evaluation of Thermal Comfort and Night Ventilation in a Historic Office Building in Nordic Climate." Licentiate thesis, Högskolan i Gävle, Energisystem och byggnadsteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-33941.
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Envelopes with low thermal performance are common characteristics in European historic buildings resulting in insufficient thermal comfort and higher energy use compared to modern buildings. There are different types of applications for the European historic buildings such as historic churches, historic museums, historic theatres, etc. In historic buildings refurbished to offices, it is vital to improve thermal comfort for the staff. Improving thermal comfort should not increase, preferably reduce, energy use in the building. The overall aim in this research is to explore how to improve thermal comfort in historic buildings without increasing, preferably reducing, energy use with the application of non-intrusive methods. This is done in form of a case study in Sweden. Thermal comfort issues in the case study building are determined through a field study. The methods include field measurements with thermal comfort equipment, data logging on BMS, and evaluating the occupant’s perception of a summer and a winter period indoor environment using a standardized questionnaire. According to questionnaire and thermal comfort measurements results, it is revealed that the summer period has the most dissatisfied occupants, while winter thermal comfort is satisfactory – but not exceptionally good. Accordingly, natural heat sinks could be used in form of NV, as a non/intrusive method, in order to improve thermal comfort in the building. For the historic building equipped with mechanical ventilation, NV strategy has the potential to both improve thermal comfort and reduce the total electricity use for cooling (i.e. electricity use in the cooling machine + the electricity use in the ventilation unit’s fans). It could decrease the percentage of exceedance hours in offices by up to 33% and reduce the total electricity use for cooling by up to 40%. The optimal (maximum) NV rate (i.e. the potential of NV strategy) is dependent on the thermal mass capacity of the building, the available NV cooling potential (dependent on the ambient air temperature), COP value of the cooling machine, the SFP model of the fans (low SFP value for high NV rate is optimal), and the offices’ door scheme (open or closed doors).
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Kong, Jing. "Experimental and Numerical Investigations of Roof-top Solar Chimney for Building Ventilation." Thesis, The University of Sydney, 2019. https://hdl.handle.net/2123/21284.
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Natural ventilation system has attracted massive attention in recent years due to the increasing energy consumption associated with mechanical ventilation systems in buildings. Solar chimney is a bioclimatic design and can promote ventilation by taking advantage of the thermal buoyancy effect. In this study, a small-scale roof-top solar chimney is investigated. The present project focuses on optimising the solar chimney performance by considering three main design parameters: the inclination angle, the incoming solar radiation represented by a heat flux, and the air gap width. Computational fluid dynamics (CFD) simulations have been carried out. The numerical results reveal that both higher heat flux and steeper inclination angle have a positive impact on the solar chimney ventilation performance, while large air gap width may reduce the mass flow rate due to the occurrence of reverse flow. Further, a procedure of using the simulation results to estimate the ventilation performance of solar chimney at various inclination angles under real-life conditions is described. In addition, an experimental solar chimney model has been designed, constructed and tested. Three experimental methods (direct measurements, smoke visualization and Schlieren) are adopted to obtain the temperature and flow field. The experimental data is compared against the numerical data. It is found that the outlet mass flow rate measured by the experiments is around 20% lower than the simulation result. This is mainly because the heat loss near the glazing and side walls is neglected in the numerical simulation. For chimney with smaller inclination angle, the discrepancy between the mass flow rates obtained with numerical and experimental investigations is smaller. One possible cause of the discrepancy is that the thermal stratification has an impact on the solar chimney performance.
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Ahmad, Mardiana Idayu. "Novel heat recovery systems for building applications." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/13852/.
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The work presented in this thesis will explore the development of novel heat recovery systems coupled with low carbon technologies, and its integration to become one device with multifunction (building integrated heat recovery/cooling/air dehumidifier. In the first part of this thesis, an experimental performance of an individual heat recovery unit using Micro Heat and Mass Cycle Core (MHM3C) made of fibre papers with cross flow arrangement has been carried out. The unit was tested in an environmental control chamber to investigate the effects of various parameters on the performance of heat/energy recovery unit. The results showed that as the airflow rate and temperature change increase, the efficiency decreases whilst recovered energy increases. Integrating heat recovery system in energy-efficient system represents significant progress for building applications. As part of the research, the integration of heat recovery using a cross-flow fixed-plate with wind-catcher and cellulose fibre papers of evaporative cooling units have allowed part of the energy to be recovered with the efficiency of heat recovery unit ranged from 50 to 70%, cooling efficiency ranged from 31 to 54%. In another case, the integration of heat recovery system with building part so called building integrated heat recovery (BIHR) was explored using polycarbonate plate with counter-flow arrangement. It introduces a new approach to MVHR system, an established technology that uses a modified insulation panel, linking the inside and outside of a building, to recover heat while extracting waste air and supplying fresh air. In this configuration it is not only acts a heat recovery, but also as a contribution to building thermal insulation. From the experiments conducted, it was found that through an energy balance on the structure, the efficiency of BIHR prototype was found to be 50 to 61.1 % depending on the airflow rate. This efficiency increases to the highest value of 83.3% in a full-scale measurement on a real building in Ashford, Kent as the area of heat transfer surface increases. The increasing of heat surface area again proved a better performance in terms of efficiency as the results on another full scale measurement on a real house in Hastings, Sussex showed to be 86.2 to 91.7%. With the aiming to have a high performance system, a new improvement design of BIHR' corrugated polycarbonate channels with four airstreams has significant advantages over the previous prototype BIHR with two airstreams. The recovered heat is increased by more than 50%. With the issue of thermal comfort in hot region area and problems with conventional air conditioning system, a study of BIHR system with fibre wick structure for different hot (summer) air conditions using different working fluids was carried out. For the first case, water was used to give a direct evaporative cooling effect which is suitable to evaluate the system performance under hot and dry climatic conditions and the second case, potassium formate (HCOOK) solution was used as liquid desiccant for dehumidification under hot and humid climate conditions. By supplying the water over the fibre wick structure, with a constant airflow rate of 0.0157m3/s, the efficiency increased with increasing intake air temperature. The efficiency ranged from 20 to 42.4% corresponding to the minimum and maximum of intake air temperature of 25°C and 38.2°C, respectively. With the variation of airflow rate, the efficiency of the system was found to be 53.2 to 60%. In second case, the HCOOK solution with concentration of 68.6% has been selected as the desiccant and for a defined airflow rate of 0.0157m3/s, heat recovery efficiency of about 54%, a lower desiccant temperature of 20°C, with higher intake air temperature and relative humidity produces a better dehumidification performance with a good moisture absorption capacity. Therefore, this system is expected to be used efficiently in hot and humid regions. The research is novel in the following ways: • The development of multifunction device in one system; building integrated, heat recovery, cooling, desiccant dehumidification. • The design and development of BIHR is an advanced technology of building thermal insulation and heat recovery. The novel BIHR -fibre wick cooling/dehumidification system has the potential to compete with conventional air conditioning systems under conditions involving high temperature and high moisture load.
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Gaidukov, Vladimir A. "Multiple criteria optimisaiton of building heating systems." Thesis, De Montfort University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391425.
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Pinnock, David J. "An investigation into the influence of wind in single-sided natural ventilation." Thesis, Loughborough University, 2000. https://dspace.lboro.ac.uk/2134/7465.
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In the present energy and CO2 emission conscious climate natural ventilation is undergoing increasingly intensive research. Buildings located in a sheltered in-fill location subject to single-sided natural ventilation are a common occurrence. However, the combination of stack effect and wind effect induced natural ventilation rates is not well defined. This thesis investigates the influence of wind on a sheltered building subject to single-sided natural ventilation. Full-scale experiments were undertaken over a wide variety of prevailing conditions on a suitable test cell to provide the measurements for the investigation. The analysis established that the flow/pressure drop relationship representing the airflow across the boundary of the building was best described by a power law relationship with an index of n=0.6348, rather than the conventional Bernoulli equation (which reflects a special case of the power law relationship when the index n=0.5). "Warren" plots, modified to reflect the power law flow/pressure drop relationship, identified stack effect dominance for the test cell. However, the wind was shown to influence the single-sided natural ventilation rates by virtue of the wind direction altering the flow path through the openings in the building and, so, affecting the flow characteristics of the openings. The investigation enabled a prediction model to be developed whereby the natural ventilation rates in the test cell subject to single-sided natural ventilation could be predicted from internal and external temperature and wind direction. Validation of the model identified an over-prediction for high stack effect driving forces and underprediction for low driving forces. The over- and under-prediction was concluded to be the result of incorporating the flow characteristics of the building openings as constant values. The flow characteristics should be treated as a variable function of wind direction and the stack effect driving force.
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Akbari, Keramatollah. "Impact of Radon Ventilation on Indoor Air Quality and Building Energy saving." Licentiate thesis, Mälardalen University, School of Sustainable Development of Society and Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7286.
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Industrial living is caused much people do live and work in closed and confined places; offices and residential buildings. This is why in this new world more fresh air which is generally provided by forced ventilation plays a vital role in living of human being. Furthermore because of many different indoor pollutants, like radon and artificial pollutants, the amount of fresh air and in turn the energy consumption has increased. This energy consumption related to ventilation has reached up to about 30 percent of energy used of building section. So making interaction between indoor air quality (IAQ) and optimization of energy saving is a necessary work. Radon as a natural pollutant is occurred in environment and in many countries threatens people health whereas is called the second causes of cancer. For reducing radon concentration in residential building at the acceptable level forced ventilation is used usually. Ventilation can improve IAQ but in the other side would increase the energy consumption in building sector and just now the contribution of ventilation exceeds up 50 percent of building sector's share. The aim of this thesis is to study the impact of ventilation on indoor radon by using Computational Fluid Dynamics (CFD) to achieve indoor air quality and energy efficiency. Application of CFD as a new technology, because of its cost and time savings, and on the other side, of its flexibility and precision is increasingly grown and can be used as a very important and valuable tool for the prediction and measurement of radon distribution in a ventilated building . Currently, measurement techniques and proposed standards and regulations of indoor pollutants and ventilation, particularly related to indoor radon cannot be able to provide a secure, safe and energy efficient indoor climate. This is why the indoor airflow distribution is very complex and with changing building geometry and operation condition, the treatment of air flow pattern, substantially would be changed, whereas the rules are usually independent of the buildings features. Furthermore, the indoor standards and regulations are based on average amount of pollutants in a room, whereas the pollutant distributions aren't identical and are varied throughout the room. Then the current techniques aren't so exactly valuable and acceptable.
From different methods which is privilege to control pollutants, ventilation method is applicable in existing buildings. Designing effective ventilation can reduce radon concentration to very level low with regarding energy conservation remarks.
This thesis presents results from simulation studies on ventilation and radon mitigation in residential buildings, in view points of indoor air quality and energy savings. The CFD technique is applied to predict, visualize and calculate of mixture radon-air flow. The distribution of indoor radon concentration, air velocity and room temperature also have considered together for achieving indoor air quality and energy saving. The results are also compared with the experimental data and related previous works.
It was found that with increasing ventilation rate, the radon concentration is decreased, but the location of ventilation system is also important. From the simulation results, it is observed that within the ventilated room, there are some zones, which are good for living and somewhere is more polluted. The traditional radon detectors basically show the average value of radon content in 1m3 of air. That is why detector measuring is not exact and safe.
Simulation results proved that floor heat can be supported ventilation effect and speed up the mixture movement. Floor heating reinforces the buoyancy effect, which is useful to reduce radon content in the floor (seating area) and then lower ventilation rate can be applied.
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Hult, Erin L. (Erin Luelle) 1982. "Experimental simulation of wind driven cross-ventilation in a naturally ventilated building." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32808.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (p. 29).
A device was designed and constructed to simulate cross-ventilation through a building due to natural wind. The wind driver device was designed for use with a one tenth scale model of an open floor plan office building in Luton, England. The air flow patterns produced by the wind driver were observed, and the uniformity of the velocity of the flows into the model windows was measured for the three settings of the wind driver fans. The temperatures and velocities of flows on the interior of the building and at the exhaust windows were also examined. The wind driver device was capable of producing uniform velocities across the face of the model to within 20 to 27%, depending on the fan setting. The consistency of certain features of the velocity distributions produced by the wind driver operating at different speeds suggest that improvements made to the design of the wind driver could lower this variation to about 15%. The velocities measured on the interior of the model seem consistent with interior velocities in the Luton building, although further experimentation is needed to confirm this trend. Cross-ventilation was effective in reducing interior model temperatures by up to 10⁰C from the natural convection case.
by Erin L. Hult.
S.B.
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Gough, Hannah. "Effects of meteorological conditions on building natural ventilation in idealised urban settings." Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/71951/.
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With 50 % of the worlds population dwelling in urban environments and over 70 % of people’s time is spent indoors (at home, work or in vehicles). It is important to understand how the urban area effects the internal-external air exchange for buildings and how this may impact on the occupants, though this will differ depending on location. The urban area is complex, requiring multidisciplinary expertise in order to understand the driving features. Urban areas may be simplified down for study to reduce some of the complexity. The study undertaken at Silsoe, UK, used a full-scale staggered array of nine 6 m3 cubes to gain an understanding of the effects of meteorological variables on the natural ventilation rate and pressure coefficient. After 6 months 8 cubes were removed, leaving the instrumented cube isolated for 2 months. All equipment logged constantly, creating a dataset which covers a wide range of wind directions, wind speeds, temperature differences and atmospheric stabilities making the dataset unique from previous work. Changes in wind direction cause changes in the pressure coefficient for both isolated and array cases. However defining wind direction is difficult for the array due to the complex interaction of obstacle wakes. The relation between reference and local wind directions is non-linear. The flow within the array was dominated by mechanical turbulence generated by the wakes of the array elements, with the local turbulence intensity being 7 to 10 times greater than for an isolated cube. The presence of an opening had no effect on the pressure coefficient when acting as an inlet. Stability was found to have no effect due to the building being low-rise and the effects of turbulence could not be discerned from 30 minute averages for both pressure coefficient and ventilation measurements. The full-scale data were compared to a wind tunnel model of the site. This allowed for increased array sizes to be used. It was found that the length and size of the rows have a non-linear effect on the pressure coefficient of a cube within the array, with a limited array reducing the pressure coefficient by 10 to 50 % ± 5 % depending on measurement location. Pre-existing models predict the pressure coefficient for an isolated cube well, but do not accurately predict the pressure coefficient for a limited array due to the lack of wind direction and shielding terms. This is also true for the full-scale data. The three methods used to predict ventilation rate (tracer gas decay, pressure difference and the volumetric method) were all affected by different variables such as the presence of thermally driven ventilation, wind direction, location of the wind speed measurement and amount of turbulence within the flow. The difference in the volumetric flow methods depended on the wind speed measurement used, highlighting the difficulty in gaining an accurate representation of ventilation rate using wind speed alone, especially in an urban area. All three methods show more agreement for the array cases than for the isolated cube cases. Pre-existing empirical models of urban wind speed (CIBSE), pressure coefficient (ASHRAE and AIVC) and ventilation rate do not capture the dual behaviour of the ratio of local and reference wind speeds found for the array. This dual behaviour is demonstrated for 1, 5, 10, 30 and 60 minute averaging periods. This behaviour is not correlated to changes in wind direction, the turbulence or speed of the oncoming flow or internal-external temperature differences. A combination of frontal area density, sheltering factor, wind speed, wind direction, opening location and temperature differences within a ventilation model is required to accurately predict ventilation rate.
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Al-Qahtani, Turki Haif. "An improved design of wind towers for wind induced natural ventilation." Thesis, University of Bath, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323566.
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Jonsson, Reine. "Energieffektivisering i flerbostadshus : Undersökning av lönsamheten med energieffektivare ventilation." Thesis, Mälardalen University, School of Sustainable Development of Society and Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7441.
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This thesis is based on a case study for the real estate manager Mimer in Västerås. Mimer provides a great deal of this city’s rental apartments. Many of their buildings have ventilation systems with a type of heat-recovery called “heatpipe”. This case study focuses on two buildings which have certain problems with these heatpipes. The recovery rates of the existing systems are low, and one building suffers from a warm indoor climate in the summertime. Problems with the indoor climate seem to stem from a faulty installation of the heatpipe. This building does also have considerably higher energy consumption than the other one, which leads suspicions to overloaded fan motors.
The main purpose of this study is to retrieve information about the present situation energy- and ecomonywise. A new type of heat recovery and new fans has been chosen by Mimer in order to calculate expected new energy consumption for these buildings. These values will lead to a few LCC calculations which show life cycle costs for the existing systems and the new systems. Based on the LCC calculations one or more options will be chosen as a recommended action for the ventilation systems. The recommendations will be analysed and discussed from different point of views that are relevant for a real estate manager.
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Gross, Steven James. "A Feasibility Study of Model-Based Natural Ventilation Control in a Midrise Student Dormitory Building." PDXScholar, 2011. http://pdxscholar.library.pdx.edu/open_access_etds/449.
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Past research has shown that natural ventilation can be used to satisfy upwards of 98% of the yearly cooling demand when utilized in the appropriate climate zone. Yet widespread implementation of natural ventilation has been limited in practice. This delay in market adoption is mainly due to lack of effective and reliable control. Historically, control of natural ventilation was left to the occupant (i.e. they are responsible for opening and closing their windows) because occupants are more readily satisfied when given control of the indoor environment. This strategy has been shown to be effective during summer months, but can lead to both over and under ventilation, as well as the associated unnecessary energy waste during the winter months. This research presents the development and evaluation of a model-based control algorithm for natural ventilation. The proposed controller is designed to modulate the operable windows based on ambient temperature, wind speed, wind direction, solar radiation, indoor temperature and other building characteristics to ensure adequate ventilation and thermal comfort throughout the year without the use of mechanical ventilation and cooling systems. A midrise student dormitory building, located in Portland OR, has been used to demonstrate the performance of the proposed controller. Simulation results show that the model-based controller is able to reduce under-ventilated hours to 6.2% of the summer season (June - September) and 2.5% of the winter (October - May) while preventing over-heating during 99% of the year. In addition, the model-based-controller reduces the yearly energy cost by 33% when compared to a conventional heat pump system. As a proactive control, model-based control has been used in a wide range of building control applications. This research serves as proof-of-concept that it can be used to control operable windows to provide adequate ventilation year-round without significantly affecting thermal comfort. The resulting control algorithm significantly improves the reliability of natural ventilation design and could lead to a wider adoption of natural ventilation in appropriate climate zones.
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Cook, Malcolm J. "An evaluation of computational fluid dynamics for modelling buoyancy-driven displacement ventilation." Thesis, De Montfort University, 1998. http://hdl.handle.net/2086/4168.
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Lugg, Andrew. "Energy and cost efficient fuzzy environmental services control strategies for achieving high standards of indoor environmental quality and human comfort." Thesis, Cranfield University, 1999. http://hdl.handle.net/1826/4198.
Full textAbstract:
Building designers aim to create buildings with high quality internal environments
which are energy and cost efficient in their use. Failure to attain these objectives
simultaneously can lead to reduced building occupant productivities. An important
aspect of the building services system which can have a major effect on the provision of
occupant comfort within a building is the adopted control strategy.
The research project investigated the use of fuzzy control strategies as a means of
achieving good standards of comfort provision for occupants while maintaining or
improving energy and cost efficiencies for the operation of the building HVAC services.
This represented a multi-variant controls objective which was capable of being fulfilled
by a fuzzy controller.
A one zone building computer model was developed using Matlab and Simulink
software as a platform for the development of fuzzy control strategies. The model
incorporated building services Heating Ventilating and Air-Conditioning (HVAC)
system models. A Proportional + Integral + Derivative (PID) control strategy was used
as a benchmark control methodology against which to compare the developed fuzzy
control strategies.
Three types of fuzzy controller were developed during the course of the research project.
These were a Proportional Derivative Fuzzy Controller (PDFC), a Fuzzy Ventilation
Controller, and the Fuzzy High Level Controller. The PDFC used the inputs of error and
rate of change of error from a specified zone environmental condition set point in much
the same way as a PID controller would to control the HVAC plant. Simulation results
indicated that the PDFC control strategy was capable of achieving performance levels
equal to the conventional PID control strategy. The Fuzzy Ventilation Controller was
used to control the rate of fresh outside air entering the building zone through the
mechanical ventilation system in order to make use of the "free" cooling and
dehumidification available by purging the indoor air when possible. Simulation results
showed improvements in the indoor environmental quality provided, and the energy
efficiency and cost efficiency of running the HVAC plant. Finally, the Fuzzy High Level
Controller used a fuzzy supervisor to control the actions of the fuzzy ventilation
controllers. Simulation results showed that the fuzzy supervisor was able to improve the
comfort conditions provided and the energy and cost efficiencies of the operation of the
HVAC plant when compared to the use of the fuzzy ventilation control strategies alone.
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Vazquez, Numez Bernardo. "An experimental and numerical study of forced convection in ventilated chambers." Thesis, King's College London (University of London), 1997. https://kclpure.kcl.ac.uk/portal/en/theses/an-experimental-and-numerical-study-of-forced-convection-in-ventilated-chambers(5525a851-2a87-4a65-9669-d7098efd28ac).html.
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Ratnam, Edward. "Indoor air quality simulation and feedback control." Thesis, Glasgow Caledonian University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388935.
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Pettersson, David, and Boris Yukhin. "INOMHUSMILJÖ I SMÅHUSMED FTX-VENTILATION : EN LITTERATURSTUDIE MED ENKÄTUNDERSÖKNINGAR OCHMÄTNINGAR." Thesis, Örebro universitet, Institutionen för teknik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-7397.
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Sakr, Wafa. "Impact of ventilation system operation and building products on perceived indoor air quality." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0005/MQ43651.pdf.
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Cheung, On-pong, and 張安邦. "Computational fluid dynamics simulations on the natural ventilation bahaviour within a building cluster." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45590084.
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Lindvall, Sara. "Comparison of centralized anddecentralized ventilation in amultifamily building in Stockholm : An LCA-study." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-232359.
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Construction companies in Sweden has to comply with regulations forboth indoor environment and energy performance in multifamily buildings,and they also face a growing demand for certified green buildings.In order to lower the energy demand, all potential energy savings areof interest. Recent European studies have reported that a decentralizedventilation system might have a lower energy consumption for fansthan a centralized system, and an increasing interest for decentralizedventilation in multifamily buildings has been noted among the buildingcompanies in Stockholm. However, research comparing the environmentalimpact from the whole life cycle seem to be missing. In this thesis,an LCA-comparison of centralized and decentralized ventilation was performedfor a case building in the outskirts of Stockholm, considering alifetime of 50 years. The energy performance was also compared, in relationto Swedish building regulations, and the initial costs were estimatedfor both systems. The LCA-study was carried out in SimaPro, usingEcoinvent 3 as inventory database and ReCiPe 2016 Endpoint (H) asimpact assessment tool. The results showed that if the pressure dropacross supply air diffusers was kept at 70 Pa in the decentralized system,energy for fans was 19% lower than in the centralized system, and ata supply air diffuser pressure drop of 30 Pa the corresponding energysaving was 44%. This led to lower environmental impact on resources,human health and ecosystems for the decentralized system. When theair supply temperature was raised from 16C to 21C, the differences inenvironmental impact increased between the systems due to the fact thatdistrict heating was employed for air heating in the centralized systemwhile Swedish electricity mix was used in the decentralized system. Productionof products only had limited impact on the LCA-results, whiletransports and maintenance had no impact on the results at all. Theenergy performance in relation to Swedish building regulations was bestfor the decentralized system, if air heating was minimized. Both energyand LCA-results were highly dependent on the choice of pressure dropover supply diffusers in the decentralized system, indicating that the systemperformance is sensitive to relatively small changes in pressure dropdue to the low efficiencies of the small fans. The initial costs were estimatedto be 27% higher for the decentralized system, and an increasewith 25 m2 in salable area would be required in the case building to coverfor the higher cost. Further research regarding long-term functionalitywould be valuable in order to evaluate quality aspects and operationaldifferences between the systems. Also, a more thorough inventory of environmentalimpact from district heating generation and a life cycle costanalysis would be welcome.Svenska byggföretag behöver förhålla sig till regler gällande både inomhusklimatoch energiprestanda i flerbostadshus, och de möter ocksåen växande efterfrågan på miljöcertifierade byggnader. Varje möjlig energibesparingär därför av intresse i byggnadens projekteringsfas. Nyligengenomförda europeiska studier har rapporterat att decentraliserade ventilationssystemkan ha ett lägre energibehov för fläktarbetet jämfört medcentraliserade system, och i Stockholm verkar intresset för decentraliseratventilationssystem i flerbostadshus ha ökat bland byggbolagen. Jämförandestudier av miljöeffekter med ett livscykelperspektiv tycks docksaknas. I denna uppsats genomfördes en LCA-jämförelse av centraliseratoch decentraliserat ventilationssystem som en fallstudie på en byggnadi utkanten av Stockholm, med avseende på 50 års livscykel. Även energiprestandanjämfördes, i relation till svenska byggregler, och de initialakostnaderna uppskattades för båda systemen. LCA-studien gjordes medhjälp av SimaPro, där databasen Ecoinvent 3 användes för inventeringoch ReCiPe 2016 Endpoint (H) för utvärdering av miljöeffekter. Resultatenvisade att det decentraliserade systemet förbrukade 19% mindrefläktenergi då tryckfallet över tilluftsdonen sattes till 70 Pa, respektive44% mindre om tryckfallet sattes till 30 Pa istället. Detta ledde till enlägre miljöpåverkan på resurser, folkhälsa och ekosystem för det decentraliseradesystemet. När tilluftstemperaturen höjdes från 16C till 21Cökade skillnaderna i miljöeffekter mellan systemen eftersom fjärrvärmeanvändes som uppvärmning i det centraliserade systemet medan svenskelmix användes i det decentraliserade. Tillverkning av produkter hadeendast begränsad effekt på resultaten, medan transporter och underhållinte alls påverkade resultaten. Energiprestandan i relation till svenskabyggregler var bäst i det decentraliserade systemet, förutsatt att värmningav luften minimerades. Både energi- och LCA-resultat berodde tillstor del på valet av tryckfall över tilluftsdonen, vilket indikerar att systemetsprestanda är känsligt för relativt små förändringar i tryckfall p.g.a.de låga verkningsgraderna hos de små fläktarna. De initiala kostnadernauppskattades till att vara 27% högre för det decentraliserade systemet,och en ökning av den säljbara ytan med 25 m2 skulle krävas för byggnadeni fallstudien för att täcka denna extra kostnad. Ytterligare forskningpå långsiktig funktionalitet vore värdefullt för att utvärdera kvalitetsaspekteroch skillnader i driftegenskaper mellan systemen. Även en mernoggrann utvärdering av miljöeffekter från fjärrvärme samt livscykelkostnadervore välkommet.
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Wang, Haoyu. "Combined Solar Chimney and Water Wall for Enhancing Building Ventilation and Thermal Comfort." Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/23384.
Full textAbstract:
This thesis is concerned with a window-sized combined solar chimney and water wall system as a natural ventilation and thermal comfort strategy. In this system, the water wall takes the place of the absorber wall of a conventional solar chimney and retains part of the incident solar radiation while allowing the rest into the room. When there is no solar radiation, the heat stored in the water wall is released to the solar chimney to maintain ventilation. During the night, the water wall also acts as a moderate heating source for the room to which the combined system is attached. The combined system is investigated for the mild winter conditions of Sydney, Australia, through both theoretical modeling and numerical simulations. It is found that the combined system is capable of providing the room with sufficient around-the-clock ventilation and at the same time preventing the room from being cooled down too quickly at night. It is also revealed that, while the ventilation rate is sensitive to the variations of the air gap width, the glass panel thickness is the key parameter to the improvements on both the ventilation rate and the room temperature. Inspired by the oscillating behaviour of the ventilation rate observed in a number of cases, the instabilities of the coupled thermal boundary layers at the air-water interface in a differentially heated dual-chamber cavity filled with air and water respectively are researched into through direct numerical simulations. It is found that, over the range of the Rayleigh numbers in discussion, the air layer near the partition becomes absolutely unstable, and the water layer on the other side of the partition is mostly convectively unstable and therefore oscillates at certain frequencies inherited from the air side. Compared to A_water, A_air largely influences the dominant instability modes of the air layer and consequently that of the water layer. It is further found that the dominant instability modes depend on the Ra.
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Cheng, Charles Chor Kwan. "Wind-induced natural ventilation of the refuge floor of a high-rise building in Hong Kong." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16400/1/Charles_Cheng_Thesis.pdf.
Full textAbstract:
An important element in the building fire safety of high-rise buildings in Hong Kong since 1996 has been the use of refuge floors in the building's evacuation system. To prevent smoke collecting and remaining in the refuge floors, the Building Code of Hong Kong requires these floors to have openings on opposite sides to provide adequate wind-induced ventilation. Other researchers using CFD simulations without wind tunnel verification have indicated that under certain conditions smoke could still remain on these floors and thereby reducing the fire safety of the refuge floors. This thesis explores these situations and presents a detailed scientific investigation of the wind movement in and around a refuge floor at mid-height of a high-rise building using wind tunnel testing together with CFD simulations (using CFD CFX-5.6 package). Besides identifying problem areas for smoke logging, this thesis also identifies how the design of a refuge floor can be modified to improve its fire safety.
A significant factor on the fire safety of a refuge floor is the blocking effect of the building's central core and its effect on the wind-induced ventilation. Under Hong Kong Building Code, the central core can occupy up to 50% of the refuge floor. Previous investigators did not take into consideration the effect of the maximum core size on natural ventilation of the refuge floor. This thesis investigates the worst case scenario for a refuge floor that has a core occupying 50% of the floor and has two solid walls on opposite side of the floor to identify the problem areas where smoke could collect and remain.
In exploring the worst case scenario with two parallel solid walls, the investigations revealed that the ceiling height and the wind direction have a significant effect on the wind ventilation of the refuge floor. These factors were not identified by previous investigators. In the case of the ceiling height, it was found that the head height of the refuge floor should be greater than 0.02 times the building height to achieve the desirable wind environment on the refuge floor. Regarding wind directions, the wind from most angles escapes the floor via the channel-like corridors next to the central core of the building. The main problem area occurred when the wind was perpendicular to the solid side walls. This resulted in noticeable stagnant areas where smoke could remain.
To validate the CFD method used in the thesis, wind tunnel experiments were performed to provide the scientific field velocity data of wind flowing over the building and in the refuge floor located at mid-height of the building. Earlier researchers of the refuge floor did not have access to wind tunnel data of a refuge floor. In comparing the wind tunnel experiments with the CFD simulations used in the thesis, acceptable agreement was achieved. These results make it possible for a significant reduction in the CFD computational effort that previous studies required.
Based on the findings of the investigations undertaken, design recommendations are proposed to improve the fire safety of the refuge floor in multistorey buildings in Hong Kong.
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Cheng, Charles Chor Kwan. "Wind-induced natural ventilation of the refuge floor of a high-rise building in Hong Kong." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16400/.
Full textAbstract:
An important element in the building fire safety of high-rise buildings in Hong Kong since 1996 has been the use of refuge floors in the building's evacuation system. To prevent smoke collecting and remaining in the refuge floors, the Building Code of Hong Kong requires these floors to have openings on opposite sides to provide adequate wind-induced ventilation. Other researchers using CFD simulations without wind tunnel verification have indicated that under certain conditions smoke could still remain on these floors and thereby reducing the fire safety of the refuge floors. This thesis explores these situations and presents a detailed scientific investigation of the wind movement in and around a refuge floor at mid-height of a high-rise building using wind tunnel testing together with CFD simulations (using CFD CFX-5.6 package). Besides identifying problem areas for smoke logging, this thesis also identifies how the design of a refuge floor can be modified to improve its fire safety. A significant factor on the fire safety of a refuge floor is the blocking effect of the building's central core and its effect on the wind-induced ventilation. Under Hong Kong Building Code, the central core can occupy up to 50% of the refuge floor. Previous investigators did not take into consideration the effect of the maximum core size on natural ventilation of the refuge floor. This thesis investigates the worst case scenario for a refuge floor that has a core occupying 50% of the floor and has two solid walls on opposite side of the floor to identify the problem areas where smoke could collect and remain. In exploring the worst case scenario with two parallel solid walls, the investigations revealed that the ceiling height and the wind direction have a significant effect on the wind ventilation of the refuge floor. These factors were not identified by previous investigators. In the case of the ceiling height, it was found that the head height of the refuge floor should be greater than 0.02 times the building height to achieve the desirable wind environment on the refuge floor. Regarding wind directions, the wind from most angles escapes the floor via the channel-like corridors next to the central core of the building. The main problem area occurred when the wind was perpendicular to the solid side walls. This resulted in noticeable stagnant areas where smoke could remain. To validate the CFD method used in the thesis, wind tunnel experiments were performed to provide the scientific field velocity data of wind flowing over the building and in the refuge floor located at mid-height of the building. Earlier researchers of the refuge floor did not have access to wind tunnel data of a refuge floor. In comparing the wind tunnel experiments with the CFD simulations used in the thesis, acceptable agreement was achieved. These results make it possible for a significant reduction in the CFD computational effort that previous studies required. Based on the findings of the investigations undertaken, design recommendations are proposed to improve the fire safety of the refuge floor in multistorey buildings in Hong Kong.
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Fennessy, Kristian (Kristian M. ). "Addressing the problem with natural ventilation : producing a guide for designers to integrate natural ventilation into the early stages of building design." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92642.
Full textAbstract:
Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 66-69).
Currently, the United States alone is responsible for approximately twenty percent of the world's total energy consumption. This consumption is equivalent to roughly 100 quadrillion Btu of energy, or in plainer terms, over $1 trillion in energy expenditures annually. This sector alone comprises nearly half of all the energy consumed in the United States. Additionally, about seventy-five percent of all electricity produced in the U.S. is consumed by building operations. This precedent has convinced me that finding an alternative is worth the investment. The purpose of my thesis project is to explore substitutes to mechanical heating, ventilation, and air conditioning (HVAC) building systems. My project revisits the concept of natural ventilation and explores and evaluates its feasibility as an energy-saving and comfortable alternative to mechanical ventilation systems. Additionally, my project focuses on how buildings can be designed to naturally condition the indoor environments of our buildings. More specifically, I would like to help architects discover how they can utilize natural ventilation effectively. Using the TRNSYS simulation environment, I methodically show how a designer would use TRNSYS to make informed decisions about natural ventilation in their designs. My research is meant to be a valuable tool for other designers who are unsure or uncomfortable with utilizing this natural process to condition their buildings. The final deliverable of my thesis project is a comprehensive strategy for designers to incorporate natural ventilation in the early stages of their building design.
by Kristian Fennessy.
S.B.
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Yang, Tong. "CFD and field testing of a naturally ventilated full-scale building." Thesis, University of Nottingham, 2004. http://eprints.nottingham.ac.uk/10091/.
Full textAbstract:
Natural ventilation has the potential to provide good indoor air quality, thermal comfort for occupants, and can also save energy and reduce CO2 emissions. Computational fluid dynamics (CFD) offers detailed information about indoor flow patterns, air movement, temperature and local draught distribution in buildings, so it has unique advantages as an efficient and cost-effective tool for optimum design in a complex built environment. This thesis shows the use of CFD to simulate the coupled external and internal flow field around a 6m cubic building with two small openings. To study both wind driven and combined wind and buoyancy driven cross ventilation through a full-scale cubic structure, un-structured grid CFD and a steady envelope flow model were applied to calculate mean ventilation rates. To validate the CFD results, full-scale experiments were undertaken under various weather conditions in England. For wind driven ventilation RANS model predictions were proved reliable when wind directions were near normal to the ventilation openings, i.e. 0o~30o. However, when the fluctuating ventilation played a more dominant role than the mean flow (90o) RANS models were incapable of predicting the total ventilation rate. Improved results may be expected by applying more sophisticated turbulence models, such as LES, weighted quasi-steady approximations, or unsteady envelope flow models. In the thesis experience on the modelling of combined wind and thermal effects is outlined and feedback is provided to CFD code developers to enable further improvements for building ventilation studies. The full-scale field testing data from this study is valuable for comparison with wind tunnel results and validation of CFD applications.
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Zhao, Ying. "A decision-support framework for design of natural ventilation in non-residential buildings." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27061.
Full textAbstract:
This study develops a decision-support framework assisting the design of non-residential buildings with natural ventilation. The framework is composed of decision modules with input, analysis algorithms and output of natural ventilation design. The framework covers ventilation with natural driving force and mechanical-assisted ventilation. The framework has two major assessment levels: feasibility assessment and comparison of alternative natural ventilation approaches. The feasibility assessment modules assess the potential of the site with the design proposition for natural ventilation in terms of wind, temperature, humidity, noise and pollution conditions. All of the possible natural ventilation approaches and system designs are assessed by first applying constraints functions to each of the alternatives. Then the comparison of alternative approaches to natural ventilation continues by assessing the critical performance mandates that include energy savings, thermal comfort, acoustic control, indoor air quality and cost. Approaches are finally ranked based on their performance.Ph. D.
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Zhang, Taoju. "Energy simulation for improved ventilation system in a collection of Swedish multi-family houses." Thesis, Högskolan i Gävle, Energisystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-24282.
Full textAbstract:
Building sector takes a large part of Swedish domestic energy use. Swedish government had set goal that required energy consumption should decrease by 20% in year 2020 compared to 1995. Public house companies will play an important role in the process. The work studies a typical Swedish Multi-family dwelling, built in 1960s and belonging to Älvkarlebyhus AB. These buildings were given enhanced air tightness in recent years which yielded a good result. This work focuses on improving the old ventilation system and decreasing energy consumption. Building energy simulation tool IDA ICE was used to model the object building and to examine the effectiveness of the new system. The tested energy efficiency measures include upgraded ventilation system with heat exchanger, and the installation of demand control (DCV) to the ventilation. Both energy, environmental and economic aspects are considered in the study. The result showed the total energy demand decreased 35% with renovation. Total investment for all buildings correspond to 5 760 000 SEK. New system could save 237 872 SEK/year and payback time will be 24 years.
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Donovan, Richard J. (Richard James) 1974. "Green building technologies : should a developer implement photovoltaics, underfloor air distribution, and natural ventilation?" Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8262.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2001.Includes bibliographical references (p. 61-64).
This thesis explores implications of green, or environmentally sensitive, development in the commercial real estate industry. Developers, as building owners, will respond to ideas that can improve their profits, not necessarily to an environmental call to arms. The ability to lease up a development quickly is a competitive advantage that a developer can realize as increased net operating income. Green building strategies may increase the productivity of occupants, which may also help a developer differentiate a project from the competition. Three green building technologies, underfloor air distribution, photovoltaics, and natural ventilation, are examined in detail to determine if they are financially feasible for a developer to include in a commercial real estate office project. This thesis attempts to use a financial argument, to address the issue of environmental sustainable, or green, development. The results of the study are that natural ventilation and underfloor air distribution are currently promising technologies that should be seriously considered by developers. The high cost of photovoltaics, however, does not justify their current use in a commercial development. A large part of the decision to include green developments is dependent on the developer understanding his/her clients, the tenants. This thesis includes a survey of both developers and tenants in an effort to gauge their interest in green technologies and willingness to pay for them. The results of the survey are presented, and suggestions for the future of green building practices are laid out.
by Richard J. Donovan.
S.M.
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Akbari, Keramatollah. "Simulation of Indoor Radon and Energy Recovery Ventilation Systems in Residential Buildings." Doctoral thesis, Mälardalens högskola, Framtidens energi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-29274.
Full textAbstract:
This study aims to investigate the effects of ventilation rate, indoor air temperature, humidity and using a heat recovery ventilation system on indoor radon concentration and distribution. Methods employed include energy dynamic and computational fluid dynamics simulation, experimental measurement and analytical investigations. Experimental investigations primarily utilize a continuous radon meter and a detached house equipped with a recovery heat exchanger unit. The results of the dynamic simulation show that the heat recovery unit is cost-effective for the cold Swedish climate and an energy saving of about 30 kWh per floor area per year is possible, while it can be also used to lower radon level. The numerical results showed that ventilation rate and ventilation location have significant impacts on both radon content and distribution, whereas indoor air temperature only has a small effect on radon level and distribution and humidity has no impact on radon level but has a small impact on its distribution.
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Elzaidabi, Abdalla Ali Mohamed. "Low energy, wind catcher assisted indirect-evaporative cooling system for building applications." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/10703/.
Full textAbstract:
Increased consciousness of the environmental problems has aroused people’s interest of renewable energy systems, especially the application of green features in buildings. The demand for air conditioning / cooling in domestic and non-domestic buildings is rising throughout the world; this increases the reliance on conventional fuels and the global warming effect from greenhouse gas emissions. Passive cooling and energy efficient design can substantially reduce reliance on fuel based heating and cooling. Passive and Hybrid Downdraught Cooling, in different forms, is now technically viable in many parts of the world. This has been established through a combination of research projects. In some hot arid regions, a major part of the energy consumed consists of air-conditioning requirements. Alternative methods, using passive cooling techniques, can assist in reducing the conventional energy consumption in buildings. Evaporative cooling, which can be tracked back several hundreds of years in ancient Egypt and Persia [1–3], is one of the most effective strategies, because of the enormous latent heat needed for evaporation of water. Green features are architectural features used to mitigate migration of various air-borne pollutants and transmission of air from outside to indoor environment in an advantageous way [9]. The reduction of fossil fuel consumption and the associated decrease in greenhouse gas emissions are vital to combat global warming and this can be accomplished, in part, by the use of natural ventilation. To assess the performance of several innovative cooling systems devices and to develop improved models for more established technology, quantitative measurement of output was necessary. This was achieved in this study by the development of simply constructed low energy cooling systems which were calibrated by the innovative use of wind and water as a source. These devices were found to be consistent and accurate in measuring the temperature and cooling load from a number of devices. There were some problems in the original evaporative units. Therefore, a number of modifications have to be made to enhance the systems performance. The novel Windcatcher – PEC cooling system was assessed and different cooling loads were achieved.