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1
Dil, Anton J. "Markov modelling of HVAC systems." Thesis, Loughborough University, 1993. https://dspace.lboro.ac.uk/2134/7301.
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Dynamic simulations have been successfully applied to the modelling of building heating, ventilating and air-conditioning (HVAC) plant operation. These simulations are generally driven using time-series data as input. Whilst time-series simulations are effective, they tend to be expensive in terms of computer execution time. A possible method for reducing simulation time is to develop a probabilistic picture of the model, by characterising the model as being in one of several states. By determining the probability for being in each model state, predictions of long-term values of quantities of interest can then be obtained using ensemble averages. This study aims to investigate the applicability of the Markov modelling method for the above stated purpose in the simulation of HVAC systems. In addition, the questions of the degree of accuracy which can be expected, and the amount of time-savings which are possible are investigated. The investigation has found that the Markov modelling technique can be successfully applied to simulations of HVAC systems, but that assumptions commonly made concerning the independence of driving variables may often not be appropriate. An alternative approach to implementing the Markov method, taking into Z): account dependencies between driving variables is suggested, but requires further development to be fully effective. The accuracy of results has been found to be related to the sizes of the partial derivatives of the calculated quantity with respect to each of the variables on which it depends, the sizes of the variables' ranges, and the number of states assigned to each variable in developing the probabilistic picture of the model's state. A deterministic error bound for results from Markov simulations is also developed, based on these findings.
2
Unruh, Cassie, Austin Johnson, and Lisa Nordman. "Residential Telemetry Applications for HVAC Control." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595643.
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ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada<br>Much of the energy consumed in developed countries is for residential heating and cooling. Substantial savings are possible if one can monitor the indoor environment at many locations, and then actively control the heating, ventilation and air conditioning (HVAC) system. This project uses a wireless sensor array and dedicated microcontroller system to control a residential HVAC system. A low data rate, ad-hoc network of sensors is deployed throughout a residence, with the data sent to a central controller. A graphical user interface allows the resident to monitor the system status, and to set parameters.
3
Chillarige, Raghavendra Srinivas. "Development of expert systems in heating, ventilating and air-conditioning (HVAC) an energy approach /." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=849.
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Thesis (M.S.)--West Virginia University, 1999.<br>Title from document title page. Document formatted into pages; contains xi, 137 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 119-126).
4
Smith, Shaun J. "Determination of k-factors of HVAC system components using measurement and CFD modelling." Thesis, University of Nottingham, 1998. http://eprints.nottingham.ac.uk/11059/.
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This thesis conforms conventional and advanced experimental techniques for the measurement of and mathematical prediction of velocity pressure-loss factors (k-factors) for fittings used in heating, ventilation and air-conditioning (HVAC) systems. After an extensive study of different tracer-gas experimental techniques, the constant injection method is applied to various duct fittings on a small scale HVAC system situated in a laboratory. The results are compared with those of experiments performed using a more conventional technique using a Pitot-static tube. The basis of the experimental procedure is to achieve an accurate method of measuring the mean air velocity within a duct. This allows an accurate estimate of the velocity pressure-lossf actor to be obtained. A wide variety of duct fittings are investigated experimentally and numerically including bends, transitions, branches, inlets, outlets and obstructions such as orifice plates, wire mesh and lateral pipe obstructions. Computational fluid dynamics (CFD) is applied to each duct fitting tested in the lab. A commercially available package FLUENT is used with a high powered computer to simulate the airflow through various duct fittings. The pressure loss and velocity vectors are predicted for each particular duct fitting and therefore a prediction for k-factors is obtained. k-factor predictions are compared with experimental results and published data given in ASHRAE and CIBSE guides in order to assess the accuracy of CFD prediction. It is shown that as an accurate method for prediction of k-factors in duct fittings, CFD is a useful tool for the design and development of HVAC systems. The application of CFD allows the designer to vary any duct component with ease to observe the effect on a particular duct fitting without incurring the expense of laboratory experimentation. It is also shown that values of current published kfactors are greatly over estimated leading to oversizing of HVAC system fans. Experimentally produced k-factors obtained using the tracer-gas method and CFD predictions are approximately 20% lower than current data available to HVAC system designers. CFD may be applied to various applications in the field of heat-pumps and refrigeration systems. A detailed investigation is carried out here to compare CFD prediction and experimental results of several low pressure and high pressure ejectors commonly found in refrigerator absorption cycles. The compressible flow of refrigerants was modelled through an ejector to obtain a prediction of the entrainment ratio ( i. e. the ejector's ability to entrain a refrigerant from an evaporator using a hot main flow through a nozzle). These predictions were then compared with experimental results and this indicated that CFD could serve as a useful tool in the design of refrigeration systems. Application of CFD has also been studied in relation to the investigation of pressure loss through different types of evaporator/condensecr oils found in heat pump systems; here the design of such coils is important to the operating efficiency. The pressure loss across heat-pipes found in ducted flows is also predicted using CFD; in this case the geometry and the thermal conditions play an important role in the overall pressure loss.
5
Li, Mingyang Kusiak Andrew. "Application of computational intelligence in modeling and optimization of HVAC systems." [Iowa City, Iowa] : University of Iowa, 2009. http://ir.uiowa.edu/etd/397.
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Lambert, Geoffrey C. "The development of a unique algorithm for the solution of HVAC system design optimisation problems." Thesis, University of Liverpool, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359199.
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Gungor, Faruk Emre. "Computer Aided Noise Prediction In Heating, Ventilating And Air Conditioning Systems." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1210087/index.pdf.
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This thesis aims at preparing a user-friendly software tool for the
prediction and analysis of the noise generated in Heating, Ventilating and Air
Conditioning (HVAC) Systems elaborating the standardized prediction formulae
and data coming from the research studies. For the analysis portion of the
software, different types of indoor noise criteria are introduced and implemented
in the software to ease the investigation of the level and the quality of the sound
perceived by the occupant in a room through such criteria. General software
structure and implementation of HVAC elements are explained by different userinterface
samples in the thesis. Several case studies are presented to demonstrate
the capabilities of the tool prepared in VISUAL BASIC programming language
within the scope of the study.
8
Sklavounos, Dimitris C. "Detection of abnormal situations and energy efficiency control in Heating Ventilation and Air Conditioning (HVAC) systems." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/12843.
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This research is related to the control of energy consumption and efficiency in building Heating Ventilation and Air Conditioning (HVAC) systems and is primarily concerned with controlling the function of heating. The main goal of this thesis is to develop a control system that can achieve the following two main control functions: a) detection of unexpected indoor conditions that may result in unnecessary power consumption and b) energy efficiency control regarding optimal balancing of two parameters: the required energy consumption for heating, versus thermal comfort of the occupants. Methods of both orientations were developed in a multi-zone space composed of nine zones where each zone is equipped with a wireless node consisting of temperature and occupancy sensors while all the scattered nodes together form a wireless sensor network (WSN). The main methods of both control functions utilize the potential of the deterministic subspace identification (SID) predictive model which provides the predicted temperature of the zones. In the main method for detecting unexpected situations that can directly affect the thermal condition of the indoor space and cause energy consumption (abnormal situations), the predictive temperature from the SID model is compared with the real temperature and thus possible temperature deviations that indicate unexpected situations are detected. The method successfully detects two situations: the high infiltration gain due to unexpected cold air intake from the external surroundings through potential unforeseen openings (windows, exterior doors, opened ceilings etc) as well as the high heat gain due to onset of fire. With the support of the statistical algorithm for abrupt change detection, Cumulative Sum (CUSUM), the detection of temperature deviations is accomplished with accuracy in a very short time. The CUSUM algorithm is first evaluated at an initial approach to detect power diversions due to the above situations caused by the aforementioned exogenous factors. The predicted temperature of the zone from the SID model utilized appropriately also by the main method of the second control function for energy efficiency control. The time needed for the temperature of a zone to reach the thermal comfort zone threshold from a low initial value is measured by the predicted temperature evolution, and this measurement bases the logic of a control criterion for applying proactive heating to the unoccupied zones or not. Additional key points for the control criterion of the method is the occupation time of the zones as well as the remaining time of the occupants in the occupied zones. Two scenarios are examined: the first scenario with two adjacent zones where the one is occupied and the other is not, and the second scenario with a multi-zone space where the occupants are moving through the zones in a cascade mode. Gama and Pareto probability distributions modeled the occupation times of the two-zone scenario while exponential distribution modeled the cascade scenario as the least favorable case. The mobility of the occupants modeled with a semi-Markov process and the method provides satisfactory and reasonable results. At an initial approach the proactive heating of the zones is evaluated with specific algorithms that handle appropriately the occupation time into the zones.
9
Sui, Di. "Characterization of HVAC operation uncertainty in EnergyPlus AHU modules." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51911.
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This study addresses 5 uncertainties that exist in the operation of HVAC systems, which will presumably affect the actual energy consumption of the HVAC system in comparison to the consumption under idealized bahavior. We consequently add these parameters and their uncertainty range into the source code, eventually resulting in an EnergyPlus program in which the HVAC operation uncertainty is embedded as so-called model form uncertainty. The upgraded EnergyPlus is tested for each parameter uncertainty separately, and to show the impact of each uncertainty albeit for hypothetical uncertainty ranges of the parameters.
10
Zajic, I. "A Hammerstein-bilinear approach with application to heating ventilation and air conditioning systems." Thesis, Coventry University, 2013. http://curve.coventry.ac.uk/open/items/bb74b3bc-b12b-4a92-8aac-9781131cc75e/1.
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This thesis considers the development of a Hammerstein-bilinear approach to non-linear systems modelling, analysis and control systems design, which builds on and extends the applicability of an existing bilinear approach. The underlying idea of the Hammerstein-bilinear approach is to use the Hammerstein-bilinear system models to capture various physical phenomena of interest and subsequently use these for model based control system designs with the premise being that of achieving enhanced control performance. The advantage of the Hammerstein-bilinear approach is that the well-structured system models allow techniques that have been originally developed for linear systems to be extended and applied, while retaining moderate complexity of the corresponding system identification schemes and nonlinear model based control designs. In recognition of the need to be able to identify the Hammerstein-bilinear models a unified suite of algorithms, being the extensions to the simplified refined instrumental variable method for parameter estimation of linear transfer function models is proposed. These algorithms are able to operate in both the continuous-time and discrete-time domains to reflect the requirements of the intended purposes of the identified models with the emphasis being placed on straightforward applicability of the developed algorithms and recognising the need to be able to operate under realistic practical system identification scenarios. Moreover, the proposed algorithms are also applicable to parameter estimation of Hammerstein and bilinear models, which are special cases of the wider Hammerstein-bilinear model class. The Hammerstein-bilinear approach has been applied to an industrial heating, ventilation and air conditioning (HVAC) system, which has also been the underlying application addressed in this thesis. A unique set of dynamic control design purpose oriented air temperature and humidity Hammerstein-bilinear models of an environmentally controlled clear room manufacturing zone has been identified. The greater insights afforded by the knowledge of the system nonlinearities then allow for enhanced control tuning of the associated commercial HVAC control system leading to an improved overall control performance.
11
Kamal, Rajeev. "Optimization and Performance Study of Select Heating Ventilation and Air Conditioning Technologies for Commercial Buildings." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6656.
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Buildings contribute a significant part to the electricity demand profile and peak demand for the electrical utilities. The addition of renewable energy generation adds additional variability and uncertainty to the power system. Demand side management in the buildings can help improve the demand profile for the utilities by shifting some of the demand from peak to off-peak times.
Heating, ventilation and air-conditioning contribute around 45% to the overall demand of a building. This research studies two strategies for reducing the peak as well as shifting some demand from peak to off-peak periods in commercial buildings:
1. Use of gas heat pumps in place of electric heat pumps, and
2. Shifting demand for air conditioning from peak to off-peak by thermal energy storage in chilled water and ice.
The first part of this study evaluates the field performance of gas engine-driven heat pumps (GEHP) tested in a commercial building in Florida. Four GEHP units of 8 Tons of Refrigeration (TR) capacity each providing air-conditioning to seven thermal zones in a commercial building, were instrumented for measuring their performance. The operation of these GEHPs was recorded for ten months, analyzed and compared with prior results reported in the literature. The instantaneous COPunit of these systems varied from 0.1 to 1.4 during typical summer week operation. The COP was low because the gas engines for the heat pumps were being used for loads that were much lower than design capacity which resulted in much lower efficiencies than expected.
The performance of equivalent electric heat pump was simulated from a building energy model developed to mimic the measured building loads. An economic comparison of GEHPs and conventional electrical heat pumps was done based on the measured and simulated results. The average performance of the GEHP units was estimated to lie between those of EER-9.2 and EER-11.8 systems. The performance of GEHP systems suffers due to lower efficiency at part load operation. The study highlighted the need for optimum system sizing for GEHP/HVAC systems to meet the building load to obtain better performance in buildings.
The second part of this study focusses on using chilled water or ice as thermal energy storage for shifting the air conditioning load from peak to off-peak in a commercial building. Thermal energy storage can play a very important role in providing demand-side management for diversifying the utility demand from buildings. Model of a large commercial office building is developed with thermal storage for cooling for peak power shifting. Three variations of the model were developed and analyzed for their performance with 1) ice storage, 2) chilled water storage with mixed storage tank and 3) chilled water storage with stratified tank, using EnergyPlus 8.5 software developed by the US Department of Energy. Operation strategy with tactical control to incorporate peak power schedule was developed using energy management system (EMS). The modeled HVAC system was optimized for minimum cost with the optimal storage capacity and chiller size using JEPlus.
Based on the simulation, an optimal storage capacity of 40-45 GJ was estimated for the large office building model along with 40% smaller chiller capacity resulting in higher chiller part-load performance. Additionally, the auxiliary system like pump and condenser were also optimized to smaller capacities and thus resulting in less power demand during operation. The overall annual saving potential was found in the range of 7-10% for cooling electricity use resulting in 10-17% reduction in costs to the consumer. A possible annual peak shifting of 25-78% was found from the simulation results after comparing with the reference models. Adopting TES in commercial buildings and achieving 25% peak shifting could result in a reduction in peak summer demand of 1398 MW in Tampa.
12
Rabie, Neil. "Energy management in a telecommunications environment with associated energy and cost modelling of HVAC." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-11102005-122948/.
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Neale, James Richard Mechanical & Manufacturing Engineering Faculty of Engineering UNSW. "Experimental and numerical investigation of noise generation from the expansion of high velocity HVAC flows on board ocean going fast ferries." Awarded by:University of New South Wales. School of Mechanical and Manufacturing Engineering, 2006. http://handle.unsw.edu.au/1959.4/28371.
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This thesis details a study of strategies used to limit the flow generated noise encountered in the outlet diffusers of high velocity heating, ventilation and air conditioning (HVAC) duct systems. The underlying noise rating criterion is drawn from the specifications covering ocean going aluminium fast ferries. Although directed primarily towards the fast ferry industry the results presented herein are applicable to other niche high velocity HVAC applications. Experimental tests have been conducted to prove the viability of a high velocity HVAC duct system in meeting airflow requirements whilst maintaining acceptable passenger cabin noise levels. A 50 mm diameter circular jet of air was expanded using a primary conical diffuser with a variety of secondary outlet configurations. Noise measurements were taken across a velocity range of 15 to 60 m/s. An optimum outlet design has been experimentally identified by varying the diffuser angle, outlet duct length and the termination grill. A 4 to 5 fold reduction in required duct area was achieved with the use of a distribution velocity of 20 to 30 ms-1, without exceeding the prescribed passenger cabin noise criteria. The geometric configuration of the diffuser outlet assembly was found to have a pronounced effect on the noise spectrum radiating from the duct outlet. The development of a numerical model capable of predicting the flow induced noise generated by airflow exiting a ventilation duct is also documented. The model employs a Large Eddy Simulation (LES) CFD model to calculate the turbulent flow field through the duct diffuser section and outlet. The flow-generated noise is then calculated using a far field acoustic postprocessor based on the Ffowcs-Williams and Hawkings integral based formulation of Lighthill???s acoustic analogy. Time varying flow field variables are used to calculate the fluctuating noise sources located at the duct outlet and the resulting far field sound pressure levels. This result is then used to calculate the corresponding far field sound intensity and sound power levels. The numerical acoustic model has been verified and validated against the measured experimental results for multiple outlet diffuser configurations.
14
Ahmedullah, Sharizal Shaik. "Integrated solar energy and absorption cooling model for HVAC (heating, ventilating, and air conditioning) applications in buildings /." Available online. Click here, 2006. http://sunshine.lib.mtu.edu/ETD/DISS/2006/MechanicalEng/ahmedullahs/diss.pdf.
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Ertug, Muzeyyen Oya. "Computer Aided Design And Simulation Of Year Around Air Conditioning-comfort Application." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610356/index.pdf.
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The aim of this thesis is to develop a computer program to design and simulate air
conditioning-comfort application of a selected building, for a year period, on an
hourly basis. In order to carry out this study, a computer program named
AHUSIM.m, is prepared with Matlab computing language.
The design and simulation procedure starts with preparing the inputs like indoor,
outdoor design states, zone cooling and heating loads, along with the general data for
conditioning-comfort equipment. The program, in light of these input data, performs
the plotting of the psychrometric processes -including the design and off design
processes- on psychrometric charts, air conditioning-comfort system selection and
calculating the response of this selected system at varying load conditions for a year.
The program also calculates the energy requirements of parts of the selected system
throughout the year. Furthermore, it lists dimensions of the parts of the air
conditioning-comfort unit, the outdoor supply air and total air flow rates, air and
water inlet and exit states.
Using numerical tools for heating, ventilating and air conditioning (HVAC) process
design and simulation, can improve energy economy and comfort which are the main
criteria of HVAC engineering. In such an attempt, major concern is the interaction
between the comfort and energy consumption. The program, by designing the system
and deciding its behavior throughout a year<br>provides a means of automatic control
considering comfort and energy economy. This program also provides a tool for
comparison of different techniques for putting limits to the relation between comfort
and energy consumption.
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Korolija, Ivan. "Heating, ventilating and air-conditioning system energy demand coupling with building loads for office buildings." Thesis, De Montfort University, 2011. http://hdl.handle.net/2086/5501.
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The UK building stock accounts for about half of all energy consumed in the UK. A large portion of the energy is consumed by nondomestic buildings. Offices and retail are the most energy intensive typologies within the nondomestic building sector, typically accounting for over 50% of the nondomestic buildings’ total energy consumption. Heating, ventilating and air conditioning (HVAC) systems are the largest energy end use in the nondomestic sector, with energy consumption close to 50% of total energy consumption. Different HVAC systems have different energy requirements when responding to the same building heating and cooling demands. On the other hand, building heating and cooling demands depend on various parameters such as building fabrics, glazing ratio, building form, occupancy pattern, and many others. HVAC system energy requirements and building energy demands can be determined by mathematical modelling. A widely accepted approach among building professionals is to use building energy simulation tools such as EnergyPlus, IES, DOE2, etc. which can analyse in detail building energy consumption. However, preparing and running simulations in such tools is usually very complicated, time consuming and costly. Their complexity has been identified as the biggest obstacle. Adequate alternatives to complex building energy simulation tools are regression models which can provide results in an easier and faster way. This research deals with the development of regression models that enable the selection of HVAC systems for office buildings. In addition, the models are able to predict annual heating, cooling and auxiliary energy requirements of different HVAC systems as a function of office building heating and cooling demands. For the first part of the data set development used for the regression analysis, a data set of office building simulation archetypes was developed. The four most typical built forms (open plan sidelit, cellular sidelit, artificially lit open plan and composite sidelit cellular around artificially lit open plan built form) were coupled with five types of building fabric and three levels of glazing ratio. Furthermore, two measures of reducing solar heat gains were considered as well as implementation of daylight control. Also, building orientation was included in the analysis. In total 3840 different office buildings were then further coupled with five different HVAC systems: variable air volume system; constant air volume system; fan coil system with dedicated air; chilled ceiling system with embedded pipes, dedicated air and radiator heating; and chilled ceiling system with exposed aluminium panels, dedicated air and radiator heating. The total number of models simulated in EnergyPlus, in order to develop the input database for regression analysis, was 23,040. The results clearly indicate that it is possible to form a reliable judgement about each different HVAC system’s heating, cooling and auxiliary energy requirements based only on office building heating and cooling demands. High coefficients of determination of the proposed regression models show that HVAC system requirements can be predicted with high accuracy. The lowest coefficient of determination among cooling regression models was 0.94 in the case of the CAV system. HVAC system heating energy requirement regression models had a coefficient of determination above 0.96. The auxiliary energy requirement models had a coefficient of determination above 0.95, except in the case of chilled ceiling systems where the coefficient of determination was around 0.87. This research demonstrates that simplified regression models can be used to provide design decisions for the office building HVAC systems studied. Such models allow more rapid determination of HVAC systems energy requirements without the need for time-consuming (hence expensive) reconfigurations and runs of the simulation program.
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Ghanta, Nikhilesh. "Meta-modeling and Optimization of Computational Fluid Dynamics (CFD) analysis in thermal comfort for energy-efficient Chilled Beams-based Heating, Ventilation and Air-Conditioning (HVAC) systems." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/126989.
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Thesis: S.M., Massachusetts Institute of Technology, Computation for Design and Optimization Program, May, 2020<br>Cataloged from the official PDF of thesis.<br>Includes bibliographical references (pages 172-178).<br>With the rapid rise in the use of air conditioning systems and technological advancements, there is an ever-increasing need for optimizing the HVAC systems for energy efficiency while maintaining adequate occupant thermal comfort. HVAC systems in buildings alone contribute to almost 15% of the overall energy consumption across all sectors in the world and optimizing this would contribute positively towards overcoming climate change and reducing the global carbon footprint. A relatively modern solution is to implement a smart building-based control system and one of the objectives of this study is to understand the physical phenomenon associated with workspaces conditioned by chilled beams and evaluated the methods to reduce energy consumption.<br>Building upon the initial work aimed at creating a workflow for a smart building, this thesis presents the results of both experimental and computational studies of occupant thermal comfort with chilled beams (primarily in conference rooms) and the various inefficiencies associated. Results from these studies have helped to inform an optimum location for the installation of a chilled beam to counter the effects of incoming solar irradiation through an external window while keeping the energy consumption low. A detailed understanding of the various parameters influencing the temperature distribution in a room with chilled beams is achieved using CFD studies and data analysis of experimental data logging.<br>The work converges into a fundamental question of where, how, and what to measure to best monitor and control the human thermal comfort, and a novel technique was presented using the existing sensors which would provide a significant improvement over other existing methods in practice. This technique was validated using a series of experiments. The thesis concludes by presenting early works on hybrid HVAC systems including chilled beams and ceiling fans for higher economic gains. Future work should seek to perform CFD simulations for a better understanding of hybrid HVAC systems, both in conference rooms and open-plan office spaces, and also to design a new sensor that could better estimate human thermal comfort.<br>by Nikhilesh Ghanta.<br>S.M.<br>S.M. Massachusetts Institute of Technology, Computation for Design and Optimization Program
18
Thompson, Glendon Raymond. "Business reasons for utilizing renewable energy applications in facilities to assist in extending the life of the heating ventilation and air conditioning systems." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22631.
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Thesis (M. S.)--Building Construction, Georgia Institute of Technology, 2008.<br>Committee Chair: Dr. Linda Thomas-Mobley; Committee Member: Dr. Del Kiernan-Lewis; Committee Member: Professor Kathy Roper.
19
Van, Rensburg Johann Francois. "Developing ESCO procedures for large telecommunication facilities using novel simulation techniques / J.F. van Rensburg." Thesis, North-West University, 2006. http://hdl.handle.net/10394/1693.
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Borges, Gabriel Adão. "Comparação do desempenho energético entre sistema de condicionamento de ar com distribuição pelo piso e pelo teto, utilizando o modelo computacional EnergyPlus." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3153/tde-13072018-111127/.
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Em pauta já há algum tempo, os impactos ambientais, possivelmente gerados pela ação humana, são cada vez mais discutidos e estudados. A busca por um desenvolvimento sustentável e formas mais eficientes do consumo de energia é abordada frequentemente. No Brasil, os edifícios comerciais e públicos apresentam alta demanda de energia elétrica e os sistemas de condicionamento de ar são responsáveis por uma parcela relevante do consumo no país. Para mitigar esse consumo, o sistema de ar condicionado distribuído pelo piso tem sido proposto como uma solução, pois este é intrinsecamente mais eficiente que o sistema de ar condicionado convencional, com distribuição de ar pelo teto. O presente trabalho tem como propósito identificar o potencial de economia de energia de um sistema de condicionamento de ar com distribuição pelo piso em relação a um sistema com distribuição pelo teto, por meio da simulação computacional. Avaliaram-se também o impacto do aumento da temperatura de insuflação e do pé-direito da edificação, além do uso de ciclo economizador (controle entálpico) aplicado aos sistemas na economia de energia. Para a modelagem computacional, realizada pela ferramenta computacional EnergyPlus, tomou-se como referência uma sala de aula que contém um sistema de condicionamento de ar com distribuição pelo piso. O primeiro sistema modelado foi pelo piso, e este serviu como base para a modelagem do sistema pelo teto. Após a criação dos modelos foram executadas as simulações cujos resultados permitiram a comparação entre os consumos de energia de cada um dos sistemas. Em conformidade com a literatura, onde se afirmam que os sistemas com distribuição de ar pelo piso são mais eficientes que os convencionais (distribuição de ar pelo teto), este trabalho também concluiu que este sistema é mais eficiente, apresentando um indicador de economia de energia da ordem de 33%, para a condição: pé-direito de 3,50 m; temperatura de insuflação de 19 °C; e controle entálpico. Os resultados desta pesquisa indicam ainda que a utilização do controle entálpico tem maior influência na economia de energia se comparada ao aumento da temperatura de insuflação ou do pé-direito.<br>On the agenda for some time, the environmental impacts, possibly generated by human action, are increasingly discussed and studied. The demand for sustainable development and more efficient ways of energy consumption is often addressed. In Brazil, commercial and public buildings have high demand for electricity and air conditioning systems are responsible for a significant portion of this consumption in the country. The underfloor air conditioning system has been proposed as a solution to mitigate such consumption because it is intrinsically more efficient than the ceiling-based air conditioning system. The present work aims to identify the energy saving potential of an air conditioning system with underfloor air distribution comparatively to a system with ceiling air distribution, through computational simulation. Also, the impact of increased supply air temperature and the floor to ceiling height, and the use of the economizer cycle (enthalpy control) was evaluated. For the computational modeling, carried out by the EnergyPlus computational tool, a classroom that contains an air conditioning system with floor distribution was used as reference. The first modeled air distribution system was the underfloor air distribution system, and this served as a basis for the modeling of the ceiling air distribution system. After performing the models, the simulations were carried out, whose results allowed the comparison the energy consumptions between the two systems. According to the literature, where it is stated that the systems with underfloor air distribution are more efficient than the conventional ones (ceiling air distribution), this work also concludes that the system with underfloor air distribution is more efficient, presenting an energy saving indicator around 33%, for the following condition: floor to ceiling height of 3.50 m; supply air temperature of 19 ° C; and enthalpy control. The results of this research also indicate that the use of the enthalpy control has a greater influence on the energy savings compared to the increase of the supply air temperature or the floor to ceiling height.
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Dombrosky, Robson Fernandes. "Eficientização de um sistema de climatização aeroportuário a partir do uso da termoacumulação." Universidade do Vale do Rio dos Sinos, 2012. http://www.repositorio.jesuita.org.br/handle/UNISINOS/4050.
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Previous issue date: 2012<br>Banco Santander / Banespa<br>O trabalho apresenta um estudo do sistema de climatização do aeroporto da cidade de Porto Alegre, visando determinar e mensurar as oportunidades de redução dos seus custos operacionais utilizando o tanque de termoacumulação já existente, recurso que por razões diversas encontra-se atualmente inoperante. Para possibilitar uma avaliação global do comportamento do sistema em estudo, tanto a edificação do terminal de passageiros quanto os equipamentos integrantes da sua planta de climatização foram modelados e simulados através do programa EnergyPlus, com uso de arquivo climático específico para a cidade de Porto Alegre. As simulações ratificaram as previsões de que o sistema de climatização do aeroporto de Porto Alegre trabalha atualmente com custos de operação superiores àqueles que poderiam ser obtidos caso o sistema de termoacumulação estivesse em operação. A economia integrada ao longo de um ano pela redução de custos com as faturas de energia do aeroporto atingiu R$ 312.206,00. Ficou evidente que a redução da demanda e consumo de energia em horário de ponta são as parcelas com maior representatividade na diminuição dos custos operacionais do sistema de climatização do aeroporto, respondendo, respectivamente, por 77% e 18% sobre todas as economias obtidas nas faturas de energia após o uso da termoacumulação. Constatouse que além da redução nos valores pagos pela utilização de energia elétrica em horário de ponta, a participação da termoacumulação possibilita também redução no consumo energético dos equipamentos da planta de climatização, motivada por estratégias de operação mais eficientes. Desta forma, considerando apenas os meses de verão, as simulações apontaram uma redução média de 11% no consumo referente aos equipamentos da planta de climatização. Se para o mesmo período forem também contabilizadas as economias devido redução de demanda e consumo em horário de ponta dos equipamentos de climatização, a redução total sobre a fatura de energia do aeroporto a partir do uso da termoacumulação situase em 30%. Outra importante questão relacionada ao uso da termoacumulação diz respeito à ampliação da capacidade frigorífica que a mesma proporciona ao sistema de climatização, efeito de elevada relevância para fazer frente ao aumento na movimentação de passageiros da aviação civil dos últimos anos. Nesse sentido, as simulações apontaram um incremento de cerca de 25% na capacidade de refrigeração da planta atual, após participação do tanque de termoacumulação. Tal efeito representa notória contribuição ao aumento da longevidade das instalações existentes, limitando ou eliminando a necessidade de maiores intervenções para aumento de capacidade de refrigeração da planta até o momento em que o terminal de passageiros venha a sofrer ampliações mais significativas.<br>The study presents the heating, ventilation and air conditioning system (HVAC) used in Porto Alegre city airport, aiming cost reductions opportunities due to its cool storage tank operation, a feature that for various reasons is currently out use. To enable a comprehensive assessment of the system’s behavior, both the passenger terminal building and HVAC equipment were modeled and simulated using the EnergyPlus software, along with the weather file that contains Porto Alegre’s meteorological data. The simulations have reaffirmed the predictions that Porto Alegre’s airport HVAC system is currently working with operating costs above those that could be obtained if the cool storage system were in operation. The integrated economy over a year by reducing costs to the electricity bills from the airport reached R$ 312.206,00. It became notorious that the reduction of demand and energy consumption during the peak hours are the most representative from all economies, accounting respectively for 77% and 18% of the total energy bills savings after cool storage tank operation. It was found that, besides the reduction in the amounts paid for electricity at peak hours, the participation of cool storage also enables reduction in energy consumption for HVAC plant equipments, driven by more efficient operating strategies. Thus, considering only the summer months, the simulations showed an average reduction of 11% in HVAC plant equipment consumption. As for the same period, if it is also accounted for the savings due to electric demand and consumption reduction during peak hours, the total energy bill reduction for the airport after applying the cool storage tank stands at 30%. Another important issue related to the use of cool storage is the HVAC cooling capacity increase, very relevant if considering the terminal passenger handling increase along last years. In that sense, the simulations showed a 25% increase in cooling capacity for the current system after the cool storage has joined the HVAC plant. This effect is a noticeable contribution to the existing installations longevity, as it limits or eliminates the need for further increase in the airport cooling capacity, not until the time when the passenger terminal may suffer significant enlargements.
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Martinovic, Zarko. "Design a PV – system for a large building." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-17539.
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This study presents the complete design of a photovoltaic system in commercial buildings. PV installation for Multiarena was primary used for internal consumption, rest of production will be sent according intentions in grid. Project presents theoretical demand calculations for building consumptions. According to the theoretical calculations numerical study has been provided by software Indoor Climate and Energy program. Detailed electric optimization strategy can be founded in project description, as well as the sizing of the photovoltaic installation and economic and financial issues related to it. Study presents several models for photovoltaic system and their economic analysis. Environmental issues can be founded at the end of the study.
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Matějíček, Michal. "Modelování, simulace a experimentální měření reakce systémů vytápění/vzduchotechniky na požadavky regulace." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392106.
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The diploma thesis deals with the behavior of technical systems of the student dormitory in Brno. The temperature and humidity climate was measured and evaluated in the building. The measurement is then compared with the computer simulation created in DesignBuilder. The geometric model of the building was created in Revit, which supports BIM technology. Based on the evaluation of the experiment, the optimization of the technical systems in the building was proposed.
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Shi, Hongsen. "Building Energy Efficiency Improvement and Thermal Comfort Diagnosis." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555110595177379.
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Kuegler, Kurt W. "Heating, ventilation and air conditioning engineering and design /." Online version of thesis, 1990. http://hdl.handle.net/1850/10982.
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Tang, Dechao. "Modelling of heating and air-conditioning system." Thesis, University of Strathclyde, 1985. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21451.
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The shortage of natural resources calls for energy conservation and the changing structure of modern science and technology makes possible the efficient dynamic energy modelling. This thesis presents a general review of existing techniques in the field of building and plant system energy modelling and concentrates on the establishment of a generalised modelling tool - the control volume conservation state space approach - to cope with the developing modern technology. The theoretical basis of this approach is discussed and verified in detail and applications demonstrated to the modelling of HVAC systems and equipment. Using this approach, any component of an HVAC system can be modelled at different levels and the qualities of the model are fully supported by the theoretical background of this approach. A computer programme for heating system simulation has been developed for the purpose of model validation and the validation efforts have been involved in the international cooperated programme of IEA Annex 10 exercises. As a part of group research, the work presented in this thesis has been involved in the development of advanced energy modelling techniques and methodology which has taken place at the ABACUS unit.
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Bouwer, Werner. "Designing a dynamic thermal and energy system simulation scheme for cross industry applications / W. Bouwer." Thesis, North-West University, 2004. http://hdl.handle.net/10394/592.
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The South African economy, which is largely based on heavy industry such as minerals
extraction and processing, is by nature very energy intensive. Based on the abundance of coal
resources, electricity in South Africa remains amongst the cheapest in the world. Whilst the
low electricity price has contributed towards a competitive position, it has also meant that our
existing electricity supply is often taken for granted. The economic and environmental
benefits of energy efficiency have been well documented. Worldwide, nations are beginning
to face up to the challenge of sustainable energy - in other words to alter the way that energy
is utilised so that social, environmental and economic aims of sustainable development are
supported.
South Africa as a developing nation recognises the need for energy efficiency, as it is the most
cost effective way of meeting the demands of sustainable development. South Africa, with its
unique economic, environmental and social challenges, stands to benefit the most from
implementing energy efficiency practices. The Energy Efficiency Strategy for South Africa
takes its mandate from the South African White Paper on Energy Policy. It is the first
consolidated governmental effort geared towards energy efficiency practices throughout
South Africa. The strategy allows for the immediate implementation of low-cost and no-cost
interventions, as well as those higher-cost measures with short payback periods. An initial
target has been set for an across sector energy efficiency improvement of 12% by 2014.
Thermal and energy system simulation is globally recognised as one of the most effective and
powerful tools to improve overall energy efficiency. However, because of the usual extreme
mathematical nature of most simulation algorithms, coupled with the historically academic
environment in which most simulation software is developed, valid perceptions exist that
system simulation is too time consuming and cumbersome. It is also commonly known that
system simulation is only effective in the hands of highly skilled operators, which are
specialists in their prospective fields. Through previous work done in the field, and the design
of a dynamic thermal and energy system simulation scheme for cross industry applications, it
was shown that system simulation has evolved to such an extent that these perceptions are not
valid any more.
The South African mining and commercial building industries are two of the major
consumers of electricity within South Africa. By improving energy efficiency practices within
the building and mining industry, large savings can be realised. An extensive investigation of
the literature showed that no general suitable computer simulation software for cross industry
mining and building thermal and energy system simulation could be found. Because the
heating, ventilation and air conditioning (HVAC) of buildings, closely relate to the ventilation
and cooling systems of mines, valuable knowledge from this field was used to identify the
requirements and specifications for the design of a new single cross industry dynamic
integrated thermal and energy system simulation tool.
VISUALQEC was designed and implemented to comply with the needs and requirements
identified. A new explicit system component model and explicit system simulation engine,
combined with a new improved simulation of mass flow through a system procedure,
suggested a marked improvement on overall simulation stability, efficiency and speed. The
commercial usability of the new simulation tool was verified for building applications by
doing an extensive building energy savings audit. The new simulation tool was further
verified by simulating the ventilation and cooling (VC) and underground pumping system of a
typical South African gold mine. Initial results proved satisfactory but, more case studies to
further verify the accuracy of the implemented cross industry thermal and energy system
simulation tool are needed. Because of the stable nature of the new VISUALQEC simulation
engine, the power of the simulation process can be further extended to the mathematical
optimisation of various system variables.
In conclusion, this study highlighted the need for new simulation procedures and system
designs for the successful implementation and creation of a single dynamic thermal and
energy system simulation tool for cross industry applications. South Africa should take full
advantage of the power of thermal and energy system simulation towards creating a more
energy efficient society.<br>Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2005.
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Leung, Wai-yip, and 梁偉業. "Indoor air quality and heating, ventilation & air conditioning systemsin office buildings." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31253787.
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Leung, Wai-yip. "Indoor air quality and heating, ventilation & air conditioning systems in office buildings /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18734315.
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Karlsson, Ejwertz Viktor. "Design of user interface for heating, ventilation and air conditioning systems." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-34806.
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The project was carried out at Karlstad University during the spring of 2014 as a degree project for a Degree of Bachelor of Science in Innovation and Design Engineering and consists of 22.5 ECTS. The supervisor was lecturer Lennart Wihk from Karlstad University. The examiner was professor Leo de Vin. The project was conducted for Swegon AB and dealt with developing a user interface for systems regulating climate parameters in indoor environments, such as hotel rooms or office environments. The area of focus has been on developing the user interface with regard to end users, giving it the right functions and making it easy to understand. Suggestions about how user interfaces of this type could look was to be delivered to Swegon. The project started with creating a foundation. This was done through literature studies, benchmarking and interviews. The information gained here was used to put together a list of requirements which was later used as a guide when developing and evaluating concepts. Idea generation-methods were used to generate concepts and the concepts were developed further to later be voted on by employees at Swegon. The votes were evaluated and two concepts were developed, based on the the voting outcome. The concepts are inspired by wishes from the end users (expressed in the interviews) and are developed with regard to principles of design. The concepts were made into prototypes, in the form of 3D-printed models. The results of the project, in short: • Two image boards. One with thoughts about functions of existing climate related user interfaces written on it, and one with thoughts of different ways of illustrating air-temperature written on it. • Explanations of and reflections about functions of four different types of user interfaces for heating, ventilation and air conditioning (HVAC) systems. • Four product semantic analyses (PSA). Three of existing user interfaces for Swegon HVAC systems and one of a concept for a user interface for HVAC systems. • Interviews with six potential end users, written down to a large extent. • A compilation of the six interviews, written down in English. • An interview with an employee at Swegon service, regarding installation of user interfaces for HVAC systems, written down to a large extent. • A functional analysis, which in this project works as a requirements specification. • 10 ideas of concepts. • Two voting-systems which are developed for use when voting for several elements which can be combined to make up a holistic concept. The voting-systems are inspired by the "morphological analysis" described by Johannesson et al. (2009). • Two final concepts of user interfaces for HVAC systems with thorough descriptions in a table in this report. The concepts are developed with respect to end users and design principles. • Simplified versions of each of the two final concepts as CAD-models and as 3D-prints.
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Kuráňová, Helena. "Výměníky tepla." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392077.
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The master thesis deals with the issue of heat recovery and efficiency of exchangers. The experimental part is dedicated to the measurment of efficiency of a plastic model of heat exchanger with atypical construction compared to a standard plate heat exchanger. For production of the heat exchangers 3D printer was used so the thesis uses the possibilities that 3D printing is offering nowadays.
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Gross, Bryan Eric. "Psychrometric application to closed loop vapor degreasing." Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/16993.
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Haque, Mohammed Ansarul. "An investigation of fresh air ventilation requirements for air-conditioned buildings in Singapore." Thesis, University of London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326153.
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Knall, Peter J. "Heating, Ventilation, and Air Conditioning Fault Detection Using the Fuzzy Jess Toolkit." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1395094657.
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Ibrahim, Sherine Taher Mahmoud. "Simulation of air-conditioning loads in electrical power systems." Thesis, University of Bath, 1997. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362265.
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Wang, Bo. "Unsteady wind effects on natural ventilation." Thesis, University of Nottingham, 2010. http://eprints.nottingham.ac.uk/11653/.
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Ventilation stacks are becoming increasingly common in the design of naturally ventilated buildings. The overall aim of the work described is ultimately to improve design procedures for such buildings. This thesis presents the experimental and theoretical investigation of unsteady wind effects on natural ventilation of a single envelope with multiple openings for both wind alone, and wind and buoyancy combined cases. There are two types of openings: namely the sharp-edged orifice and the long opening (stacks being treated as long openings). Two methods are adopted: 1) direct wind tunnel measurements using the hot-wire technique; 2) theoretical analysis using steady and unsteady envelope flow models. For the wind alone experiments, the influences of wind speed, wind direction and opening configuration on flow patterns are studied. For the wind and buoyancy combined tests, the transitional process between wind dominated and buoyancy dominated states are investigated. The direct velocity measurements provide the criteria for testing the validity of the theoretical models, and ways to improve them. Additionally, improvements are made to the experimental techniques: e.g. a precise unsteady calibration method of the hot-wire is developed; improvements of pressure measurements are also investigated. The experimental technique works well with multiple stacks. Even though small openings are used, some dependence of the mean pressure coefficient on opening configuration is observed. The theoretical models also work reasonably well with multiple stacks, yet it is observed that the accuracy of the theoretical models decrease with the increasing number of openings, and is sensitive to the chosen discharge coefficient which defines the characteristics of ventilation openings.
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Graham, W. J. "Adaptive control of wet heating systems." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370317.
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Croxford, Ben. "An intelligent, domestic central heating controller." Thesis, University of Westminster, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359206.
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Alghatam, Mohammed Jassim. "Solar ventilation and air-conditioning system investigation using the finite element method." Thesis, Loughborough University, 1985. https://dspace.lboro.ac.uk/2134/7408.
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The finite element method is used to predict numerically steady state, two-dimensional laminar and turbulent thermal buoyant and convective recirculating flows. The governing equations are solved by the finite element method using Galerkin Weighting functions, with velocity, pressure, and temperature as dependent variables. Turbulent separating, recirculating flow in the complex geometry of a room with variable inlets, outlets and convective chimney ducts is investigated. The room is ventilated/air-conditioned utilising the solar energy via a flat plate collector and solar absorption airconditioning system. For this purpose the Navier-Stokes, continuity and general energy equations are solved in a coupled form and in an uncoupled form and solutions are compared amongst themselves and with the experimental results of hot wire anemometers and thermocouples. The parts where turbulent flows occurred especially in the convective duct and the room, the flows are analysed using the Prandtl- Kolmöjorov model to depict the effective viscosity. The analogy between thermal and momentum diffusivity via Prandtl number is used to depict the turbulent conductivity from the turbulent viscosity. The length scale of turbulence is specified as an algebraic function of position from empirical data and experience of other researchers . The kinetic energy is expressed as a function of velocity at the nodes together with the turbulence intensity which varies from ~5% - ~20%. This turbulence model is used to predict the flow including its recirculations in the solar ventilated/air-conditioned room, and the fully turbulent convective channel. The analysis includes temperature and heat transfer predictions in this complex geometry of combined free and forced convection, together with buoyancy effects and turbulent transport and recirculations. Results obtained are compared with the experimental data which showed very good agreement.
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Tunzi, Michele. "Optimising the operation of hydronic heating systems in existing buildings for connection to low temperature district heating networks." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/38724/.
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This thesis presents a new method developed to adapt existing hydronic systems in buildings to take advantage of low temperature district heating (LTDH). The work carried out was performed by extensive use of buildings’ energy modelling, validated through recorded data. Two different case studies were investigated and the dynamic heat demand profiles, simulated for each building, were used to evaluate plate radiators connected to single and double string heating loops. The method considered an optimisation procedure, based on supply and return temperatures, to obtain the required logarithmic mean temperature difference (LMTD). The results of the analysis are presented as the average reduction of LMTD over the heating season compared to the base case design conditions. The developed strategy was applied to a Danish single family house from the 1930s. Firstly it was hypothesised a heating system based on double string loop. Two scenarios were investigated based on the assumption of a likely cost reduction in the end users energy bills of 1% per each 1◦C reduction of return and average supply and return temperatures. The results showed possible discounts of 14% and 16% respectively, due to more efficient operation of the radiators. For the case of single loop system, the investigated scenario assumed a cost reduction in the end users energy bill of 1% per each 1◦C lower reduction of average supply and return temperature. Although low return temperatures could not be achieved, the implementation of the method illustrates how to efficiently operate these systems and for the given scenario a possible discount of 5% was quantified. The method was also applied to a UK small scale district heating (DH) network. The analysis began by assessing the buildings of the Estate having double string plate radiator systems. Assuming a likely cost reduction in the end users energy bills of 1% per each 1◦C reduction of return temperature, the optimisation led to obtain a possible discount in the end users energy bills of 14% with a possible yearly average return temperature of 41◦C, compared to the present 55◦C. Moreover, few improvements in the operation of the heat network were proposed. It was assumed to operate the buildings with underfloor heating systems (UFH) with average supply and return temperatures of 40/30◦C, whereas the ones with plate radiators with the optimised temperatures of 81/41◦C. The results shown that an overall average return temperature of 35.6◦C can be achieved operating the heat network as suggested. This corresponds to a decrease in the average return temperature of 18.6◦C compared to the present condition and to a reduction of 10% in the distribution heat losses. Finally, the lower average return temperature achievable would guarantee a better condensation of the flue gases, improving the overall efficiency of the biomass boiler. This was quantified as a possible reduction of fuel consumption of 9% compared to present conditions.
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Nevrlý, Jaroslav. "Energeticky efektivní řadový rodinný dům." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265510.
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The main aim of the thesis was to create design documentation, energyefficient terraced house in the village of Moravian Knínice. The proposed building will be located in the vacant space between buildings. Layout of the building is limited by the size of building lots located in hillside surrounding buildings, and orientation to the cardinal. The thesis deals with the layout, building and construction, buildings, so that it effectively uses renewable energy and efficiently work with them.
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Straw, Matthew Peter. "Computation and measurement of wind induced ventilation." Thesis, University of Nottingham, 2000. http://eprints.nottingham.ac.uk/10110/.
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This thesis aims to predict wind induced ventilation of a structure through the application of current analytical techniques, computational fluid dynamics simulations and novel techniques for ventilation flows induced by turbulent mechanisms. Validation of the predictions was carried out through full-scale measurements undertaken on a purpose built test structure. The structure was of cubic design with an external dimension of 6m. The construction of this full-scale research structure at Silsoe Research Institute, Bedfordshire, England, provided a unique opportunity for undertaking full-scale experimentation on a fundamental wind engineering test case which, prior to this thesis, had only been investigated using scale models in wind tunnels and computational simulations.
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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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Waszkiewicz, Sylwia Danuta. "Adsorption refrigeration system using zeolite and methanol." Thesis, University of Bristol, 2003. http://hdl.handle.net/1983/6e735af3-f009-4b49-b7c5-68d0437a4cbb.
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Giles, Jonathon Richard. "Energy comparison of under floor air distribution heating ventilation and air conditioning systems in office buildings." [Ames, Iowa : Iowa State University], 2008.
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Ho, Wai Fuk. "Air-conditioning system design for optimum control performance in Hong Kong." Thesis, Loughborough University, 2000. https://dspace.lboro.ac.uk/2134/7242.
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Studies on design for control optimization of air-conditioning (a/c) system for better performance in Hong Kong are reported in this thesis. Typical plant configuration data was collected from an in-depth survey of a/c systems and control used in Hong Kong. Control performance has been used for the first time as an objective for optimizing a/c system designs. The study investigates and illustrates that optimization of a/c systems for application in the Hong Kong by simulation is promising and flexible. The accuracy of simulation is enhanced by using the survey data. The survey shows that some a/c control systems and their control strategies are not well considered in the design stage and their operation and set-up are not properly addressed. Hence, there exists optimization opportunities in the a/c system design and control strategies for a/c systems used in Hong Kong. Parameters affecting the control performance of a/c systems were investigated by carrying out experiments. Identified parameters are the objective function of optimization, controller settings, control valve and drive and, in case of direct digital control, sampling rate. The influence of these factors on the control performance is an essential consideration for the entire optimization process. Strategies in applying the findings in optimizing an a/c system for control performance by simulation were developed and suggested. This study provides platform for further simulation study of optimization in both methodologies and control strategies for a/c system design and operation.
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Hayat, Tariq. "Modelling, simulation and control of mine ventilation systems." Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387494.
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Chan, Hoy-Yen. "Solar facades for heating and cooling in buildings." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/12319/.
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The aim of this thesis is to study the energy performance of a building integrated heating and cooling system. The research objectives are to investigate the system operating characters, to develop mathematical models for the heating and cooling systems, to demonstrate the technologies experimentally, to identify the best designs for a combined system and to investigate the cost effectiveness of the system. The main components of the systems are the aluminium plate façade and the building wall behind it, these form a plenum between them and the air is then heated or cooled as it flows through this plenum. Mathematical models were developed based on the energy balance equations and solved by matrix inversion method. These models were then validated with experimental results. The experiments were carried out in the laboratory with a facade area of 2m2. Two designs of facade were tested, i.e. flat and transpired plates. Results showed that the transpired design gave better thermal performance; the system efficiency for the flat plate was only about 30%, whereas it was about 85% for the transpired plate. On the other hand, a cooling system with double plenums was found to be better than a single plenum. Thus, a transpired plate with two plenums was identified as the best design for space heating and cooling. The cooling efficiency was nearly 2.0 even at low solar radiation intensity. A simulation study was carried out by assuming a 40m2 of façade was installed on an office building in London. The yearly energy saving was estimated as 10,877kWh, which is equivalent to 5,874kgCO2/year of emission avoidance. The system is calculated to cost about £70/m2, and for a discount rate of 5% and 30 years of lifetime, the payback period for this system would be less than a years.
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Tang, Man-wah Myra, and 鄧敏華. "Indoor air quality and HVAC systems in institutional buildings." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31255322.
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Simons, Martin W. "The prediction of ventilation effectiveness parameters for design studies." Thesis, Coventry University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323519.
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