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Колесник, Н. С. "Оптимізація енергоефективності системи теплопостачання приватного житлового будинку." Master's thesis, Сумський державний університет, 2021. https://essuir.sumdu.edu.ua/handle/123456789/86617.
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У роботі виконано розрахунок циклу теплового насосу для контролю клімат системи приватного житлового будинку, а також опис обладнання У результаті розрахунку було підібрано модель і потужність та кількість теплових насосів для енергоефективної роботи. У результаті розрахунку було прийнято два теплові насоси ESVMO-SF-MF-140(3). Також було виконано економічний розрахунок та розрахунок заземлення приміщення тепло генераторної від ураження електричним струмом.В работе выполнен расчет цикла теплового насоса для контроля климата системы частного жилого дома. В результате расчета была подобрана модель и мощность и количество тепловых насосов для энергоэффективной работы. В результате расчета было принято два тепловых насоса ESVMO-SF-MF-140(3). Также был выполнен экономический расчет и расчет заземления помещения теплогенераторной от поражения электрическим током.
The calculation of the heat pump cycle for climate control of a private house system is performed in the work. As a result of the calculation, the model and capacity and number of heat pumps for energy efficient operation were selected. As a result of the calculation, two heat pumps ESVMO-SF-MF-140 (3) were adopted. An economic calculation was also performed and calculation of grounding of the heat generator room from electric shock.
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Molyneaux, Glenn Arthur. "Resorption cycle heat pump with ammonia-water working fluid." Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326335.
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Dahlqvist, Johan. "Impulse Turbine Efficiency Calculation Methods with Organic Rankine Cycle." Thesis, KTH, Kraft- och värmeteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-104174.
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A turbine was investigated by various methods of calculating its efficiency. The project was based on an existing impulse turbine, a one-stage turbine set in an organic Rankine cycle with the working fluid being R245fa. Various methods of loss calculation were explored in the search for a method sufficiently accurate to make valid assumptions regarding the turbine performance, while simple enough to be time efficient for use in industrial research and development. The calculations were primarily made in an isentropic manner, only taking into account losses due to the residual velocity present in the exit flow. Later, an incidence loss was incorporated in the isentropic calculations, resulting in additional losses at off-design conditions. Leaving the isentropic calculations, the work by Tournier, “Axial flow, multi-stage turbine and compressor models” was used. The work presents a method of calculating turbine losses separated into four components: profile, trailing edge, tip clearance and secondary losses. The losses applicable to the case were implemented into the model. Since the flow conditions of the present turbine are extreme, the results were not expected to coincide with the results of Tournier. In order to remedy this problem, the results were compared to results obtained through computational fluid dynamics (CFD) of the turbine. The equations purposed by Tournier were correlated in order to better match the present case. Despite that the equations by Tournier were correlated in order to adjust to the current conditions, the results of the losses calculated through the equations did not obtain results comparable to the ones of the available CFD simulations. More research within the subject is necessary, preferably using other software tools.
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Santoso, Moeljadi Christensen Richard Neils. "An alternative configuration of Rankine cycle engine-driven heat pump system /." Connect to resource, 1989. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1144698627.
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Santoso, Moeljadi. "An alternative configuration of Rankine cycle engine-driven heat pump system." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1144698627.
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Siviter, Jonathan Peter. "Increasing the efficiency of the Rankine cycle using a thermoelectric heat pump." Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5802/.
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Thermal plants operating on the Rankine cycle are by far the most common method of global electrical power generation. The Rankine cycle, first developed in the late 19th century, continues to this day to be one of the most important practical implementations of a heat engine. Innovation and enhancement of the cycle continues and today's emphasis is directed towards reduced carbon emissions from the combustion of fossil fuel as well as improvement of the absolute efficiency. This thesis presents an increase in the Rankine cycle efficiency through reducing the waste heat rejected from the process by the use of a thermoelectric heat pump. A thermoelectric heat pump converts a flow of electrical charge carriers to a flow of thermal energy via phonon transport through a semiconductor lattice, described by the Peltier effect. The heat flux through the device can be modulated by varying the electrical voltage and current applied to the semiconductor. Unlike a conventional heat pump, however, the direction of heat transport is determined by the direction of migration of the charge carriers. The efficiency with which the device operates is determined by complex relationship amongst the differential temperature across the device, the geometry of the semiconductor pellets forming the device and the electrical current flow. Peltier effect devices are typically used in small-scale refrigerators, on high-power lasers to aid cooling and to maintain the wavelength stability of optical communications networks. In this thesis the application of a heat pump to recover a portion of the waste thermal energy normally rejected from the Rankine cycle process after the re-condensation of feedwater in the condenser of a steam turbine is considered. Firstly, a theoretical statement of the required Coefficient of Performance for economic operation of such a system is derived. This is followed by an experimental investigation to determine if the calculated performance is available using today's thermoelectric technology point. The thesis then presents a rigourous analysis of novel experimental apparatus used to characterise the impact of redirecting enthalpy normally rejected from the process to instead reducing the fuel load to the plant and concludes with an assessment of the economic benefits such a heat pump system would bring.
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Oelofse, Stephanus Phillipus. "An investigation into the performance of a Rankine-heat pump combined cycle / Stephanus Phillipus Oelofse." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9185.
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The global growth in electricity consumption and the shortcomings of renewable electricity generation technologies are some of the reasons why it is still relevant to evaluate the performance of power conversion technologies that are used in fossil fuel power stations.
The power conversion technology that is widely used in fossil fuel power stations is the Rankine cycle. The goal of this study was to determine if the efficiency of a typical Rankine cycle can be improved by adding a heat pump as a bottoming cycle. Three simulation models were developed to perform this evaluation.
The first is a simulation model of a Rankine cycle. A quite detailed Rankine cycle configuration was evaluated. The simulation model was used to determine the heating requirements of the heat pump cycle as well as its operating temperature ranges. The efficiency of this Rankine cycle was calculated as 43.05 %.
A basic vapour compression cycle configuration was selected as the heat pump of the combined cycle. A simulation model of the vapour compression cycle and the interfaces with the Rankine cycle was developed as the second simulation model.
Working fluids that are typically used in vapour compression cycles cannot be used for this application, due to temperature limitations. The vapour compression cycle’s simulation model was therefore also used to calculate the coefficient of performance (COP) for various working fluids in order to select a suitable working fluid. The best cycle COP (3.015 heating) was obtained with ethanol as working fluid.
These simulation models were combined to form the simulation model of the Rankine-heat pump combined cycle. This model was used to evaluate the performance of the combined cycle for two different compressor power sources.
This study showed that the concept of using steam turbine or electrical power to drive a compressor driven vapour compression cycle in the configuration proposed here does not improve the overall efficiency of the cycle.
The reasons for this were discovered and warrant future investigation.Thesis (MIng (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2013.
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Underwood, C. P. "An investigation into the dynamic thermal modelling and capacity control of the absorption cycle heat pump." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375116.
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Yildiz, Ilhami. "Simulation of greenhouse microclimates and environmental control strategies using a Rankine cycle heat pump /." Connect to resource, 1993. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1145453202.
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Thesis (Ph. D.)--Ohio State University, 1993.Advisor: Dennis P. Stombaugh, Dept. of Agricultural Engineering. Includes bibliographical references (leaves 213-226). Available online via OhioLINK's ETD Center
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Quinn, Matthew Vincent. "The development of a capacity controlled advanced cycle air source heat pump for domestic retrofit applications." Thesis, University of Ulster, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.592665.
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Domestic heating for the majority of the housing stock within the UK and Ireland use a fossil fuel boiler, oil or gas, within a central heating system distributing heat to the living space through hydronic radiators. Current trends show a rise in the price of fossil fuels (through an increasing global demand) which is having a direct impact on the individual and the economy, increasing the price of all commodities through increased transportation costs and increasing the cost of energy (heating and electricity). The increasing costs and the environmental impact associated with the burning of fossil fuels are therefore driving the need for more renewable/more energy efficient means of supplying heat. Utilising a reversed Rankine cycle heat pump is a proven, well established method of providing high energy efficient heat transfer from a low temperature source to a high temperature sink through the manipulation of a working fluid about a pressure differential. The temperature and pressure differential across the compressor, have a large impact on the system performance. The aim of this work was to develop an air to water heat pump as an alternative to the fossil fuel boiler whilst using the existing heat distribution system and comparable water temperatures. This system could therefore be retrofitted into the majority of the existing housing stock providing an affordable energy efficient solution to the majority of homeowners whilst reducing national greenhouse gas emissions. An advanced cycle Economised Vapour Injection heat pump was utilised to improve the system efficiency when compared with a conventional system for the high temperature and pressure lift retrofit application. The COP was improved for the EVI cycle across the range of conditions tested. Between the minimum and maximum pressure differentials, the EVI cycle provided a performance improvement of between 1% and 27%. An off-the-shelf inverter was coupled to the BVI compressor to provide capacity control. The inverter-motor combination was evaluated detailing the maximum and minimum frequency limits. The heat pump performance was then evaluated between these limits comparing both the EVI and conventional cycles. As the frequency/compressor RPM was reduced, the improvement for the EVI cycle with respect to the conventional increased. The transient characteristics and the control strategies of the systems were evaluated showing large reductions of the start-up time-frame and power consumption when using the EV} cycle at increased speeds. When compare:d with the conventional cycle at 50Hz (nominal frequency), the maximum energy and time sav ings were 45% and 64%, respectively. This work concludes that th is set-up, using a nominal single speed compressor with an off-theshelf inverter is not ideal and creates reliability issues; however, it also highlights the potential benefits achievable when utilising capacity control which can be optimised by maximising the load matching range with a dedicated variable speed compressor.
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Caglar, Ahmet. "Theoretical And Experimental Performance Analysis Of A Solar Assisted Heat Pump." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/3/12607898/index.pdf.
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In this thesis, performance of a heat pump aided by solar heating system with an evacuated tubular collector has been analyzed theoretically and experimentally. For this purpose, a domestic hot water heating system has been designed, constructed and tested. The evacuated tubular solar collector has been used to achieve higher collector efficiency in winter. The fraction of the solar energy utilized has been measured experimentally and estimated theoretically. Effects of various parameters have been investigated on the performance of the proposed system.
A mathematical model was developed to investigate the effects of different environmental, design and operational parameters on the solar heating system. In order to compare the obtained theoretical results with experimental ones, an experimental study has been carried out. For that, a number of experiments have been made at the solar house of the Mechanical Engineering Department of METU. An air-to-air heat pump was integrated with an evacuated tubular solar water heater unit (closed water circulation) and the performance of it has been studied experimentally. As a result of the experimental study, the maximum value of the coefficient of performance of the solar assisted heat pump used in this study was obtained as 4.85. The second law efficiency of the system was between 4.8-27.4 %.
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Carlsson, Carin. "Modeling and Experimental Validation of a Rankine Cycle Based Exhaust WHR System for Heavy Duty Applications." Thesis, Linköpings universitet, Fordonssystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-81737.
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To increase the efficiency of the engine is one of the biggest challenges for heavy vehicles. One possible method is the Rankine based Waste Heat Recovery. Crucial for Rankine based Waste Heat Recovery is to model the temperature and the state of the working fluid. If the state of the working fluid is not determined, not only the efficiency of the system could be decreased, the components of thesystem might be damaged.A Simulink model based on the physical components in a system developed by Scania is proposed. The model for the complete system is validated against a reference model developed by Scania, and the component models are further validated against measurement data. The purpose of the model is to enable model based control, which is not possible with the reference model. The main focus on the thesis is to model the evaporation and condensation to determine state and temperature of the working fluid. The developed model is compared to a reference model with little differences for while stationary operating for both the components and the complete system. The developed model also follows the behavior from measurement data. The thesis shows that two phase modeling in Simulink is possible with models based on the physical components.
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Priedeman, Douglas Kelly. "Testing of a residential GAX absorption heat pump and chiller and verification of a computer cycle simulation /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487948440827071.
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Taheri, Hadi [Verfasser], and M. [Akademischer Betreuer] Gabi. "Numerical Investigation of Stratified Thermal Storage Tank Applied in Adsorption Heat Pump Cycle / Hadi Taheri. Betreuer: M. Gabi." Karlsruhe : KIT-Bibliothek, 2014. http://d-nb.info/1051848180/34.
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Jašek, František. "Návrh tepelného čerpadla voda-voda." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230413.
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First part of my diploma thesis contains theoretical description of compressor based heat pumps, refrigeration cycle, main components of refrigeration cycle and auxiliary equipment. Second part contains the heat pump WATER-WATER desing. It will be used for heat recovery from cogeneration units in heating plants.
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Nuutinen, Antti, and Giovanni Graziano. "Towards Flexible Cogeneration: Techno-economic Optimization of Advanced Combined Cycle Combined Heat and Power Plants integrated with Heat Pumps and Thermal Energy Storage." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-235820.
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The liberalization of electricity markets and a growing penetration of renewables is changing operation of electrical grids. The boundary conditions for the operation of conventional power plants are changing and, as such, an improved understanding of the varying loads and prices on the electricity grid is required to assess the performance of emerging combined cycle gas turbine (CCGT) concepts and to further optimize their design for these new markets in the pursuit of increasing their profitability, especially when considering combined heat and power (CHP). To increase the flexibility of CCGT-CHP plants, three new plant layouts have been investigated by integrating different storage concepts and heat pumps in key sections of the traditional plant layout. The present study analyses the influence that market has on determining the optimum CCGT-CHP plant layout that maximizes profits (in terms of plant configuration, sizing and operation strategies) for a given location nearby Turin, Italy, for which hourly electricity and heat prices, as well as meteorological data, have been gathered. A multi-parameter approach for design and operation was followed using KTH’s and EPS’ techno-economic modeling tool DYESOPT. Results are shown by means of a comparative analysis between optimal plants found for each layout and the state-of-the art CCGT-CHP. It is shown that a plant configuration in which a cold storage unit is integrated together with a heat pump at the inlet of the gas turbine unit increases the net present value of the plant by approximately 0.3% when compared against conventional plant layouts. Using the same concept with a heat pump alone can improve lifetime profitability by 1.6%. A layout where district heating supply water is preheated with a combination of a heat pump with hot thermal tank increases plant profitability by up to 0.5%. This work has been performed as part of the PUMP-HEAT project, an EU Horizon 2020 research project in which KTH collaborates with other 13 stakeholders including industry and research institutions. The results will directly influence future work of the project.
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Kožík, Martin. "Analýza investice do obnovitelných zdrojů tepla." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-399638.
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This thesis is focused on renewable energy sources, which are currently and increasingly used. Primarily for passive and low-energy houses. The principles that apply to heat pumps and solar collectors with thermal storage, which are suitable for new or older buildings, are described in detail. The thesis analyzes the thermal properties of the object under consideration and the proposed heat pump with its calculation and determination of the payback period of the investment in dependence on the analysis of energy price development in the las 10 years.
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Masson, Alan John. "An investigation into the effects of lubricating oil on heat pump evaporator performance and possible cycle improvements utilising a regenerative expansion process." Thesis, University of Ulster, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293891.
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Noubli, Halima. "Développement d’un nouveau thermo-transformateur à absorption-démixtion : optimisation conjointe du cycle et du mélange de travail." Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL089N/document.
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Ce travail porte sur l’étude d’un nouveau type de thermo-transformateur à absorption-démixtion (TTAD) utilisant un mélange présentant une lacune de miscibilité à basse température. Dans ce cycle, l’opération de séparation, est effectuée par décantation gravitaire par simple refroidissement du mélange. La séparation est ainsi énergétiquement gratuite et permet d’atteindre des rendements thermiques plus élevés que ceux des pompes à chaleur à absorption classiques dans lesquelles la séparation s’effectue par distillation.Afin de trouver des mélanges de travail pour atteindre un saut thermique de 50°C, un outil de simulation numérique a été développé pour évaluer les performances des TTAD en fonction des conditions opératoires (rapport d’alimentation et nombre d’étages de la colonne de rectification inverse) et des caractéristiques des composés du mélange de travail (Cp, Lv, paramètres caractéristiques des équilibres liquide-liquide et liquide-vapeur). L’optimisation des conditions opératoires a ainsi permis d’obtenir un saut thermique maximal de 12,4°C pour le mélange n-heptane / DMF pris comme référence. En faisant varier les propriétés des composés autour de celles de ce mélange de référence, un saut maximum de 32°C a été calculé pour un mélange fictif. L’étude de 17 mélanges réels a permis atteindre 21°C de saut thermique. Une liste d’autres mélanges à étudier a été établie. A l’aide d’une unité pilote d’une puissance de 4kW, des mesures expérimentales des performances du cycle modifié de TTAD pour le mélange n-heptane / DMF ont été réalisées et démontré la faisabilité de ce cycle même si le saut thermique de 11°C atteint au maximum est inférieur à celui calculé par simulationThis work is a study of a new type of Absorption-Demixing Heat Transformer (ADHT), using a mixture exhibiting a miscibility gap at low temperature. In this cycle, the separation step is performed by settling obtained after cooling the mixture. The separation is then energetically free and enables to reach thermal yields higher than those obtained for classical absorption heat transformers where separation is done by distillation.In order to find suitable working mixtures to reach temperature lift of 50°C, a numerical simulation tool was developed to calculate ADHT performances. This tool enabled to calculate thermal yield and thermal lift for different values of operating parameters (molar feed ratio, number of stages of rectification column) and different properties of working mixtures (Cp, Lv, parameters characterizing liquid-liquid and liquid-vapour equilibria). The best operating conditions allowed reaching a 12,4°C thermal lift for the n-heptane / DMF mixture takes as a reference mixture. By varying the mixture properties around the values of the reference mixture properties, a maximal thermal lift of 32°C was reached for an imaginary mixture. 17 real mixtures were also studied and enabled to reach a 21°C temperature lift. A list of other working mixtures that should be suitable was established. A 4 kW ADHT pilot unit was designed and built. The technical feasibility of this cycle was then experimentally demonstrated with this unit. A maximum temperature lift of 11°C was measured with the n-heptane / DMF mixture that is lower than the values calculated by simulation
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Khadra, Alaa. "Economic Performance Assessment of Three Renovated Multi-Family Houses with Different HVAC Systems." Thesis, Högskolan Dalarna, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:du-29076.
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Since the building sector is responsible for 40% of the energy consumption and 36% of CO2 emissions in the EU, the reduction of energy use has become a priority in this sector. The EU has adopted several policies to improve energy efficiency. One of these policies aims to achieve energy efficient renovations in at least 3% of buildings owned and occupied by governments annually. In Sweden, a large part of existing buildings was built between 1965 and 1974, a period commonly referred to as ‘miljonprogrammet’. Stora Tunabyggen AB, the public housing company in Borlänge municipality, begun a renovation project in the Tjärna Ängar neighborhood within the municipality with the greatest share of its buildings stock from this period. The pilot project started in 2015. The aim of this project was to renovate three buildings with similar measures, that is, by adding 150 mm attic insulation, replacing windows with higher performing ones (U-value 1 W/m ²K), by adding 50 mm of insulation to the infill walls and by the installation of flowreducing taps. The essential difference between the three renovation packages is the HVAC systems. The selected HVAC systems are (1) exhaust air heat pump, (2) mechanical ventilation with heat recovery and (3) exhaust ventilation. Life cycle cost analysis was conducted for the three building and sensitivity analysis for different values of discount rate and energy price escalation was performed. The study found that the house with exhaust ventilation has the lowest life cycle cost and the highest energy cost. The house with exhaust air heat pump has 3% higher life cycle cost and 18% lower energy use at 3% discount rate and 3% energy price escalation. The study found that mechanical ventilation with heat recovery is not profitable, although it saves energy. The sensitivity analysis has shown that the possible increment of price energy and lower discount rate give higher value for the future costs in life cycle cost analysis. This lead to the main finding of this thesis, which is that exhaust air heat pump is the best choice for the owner according to the available data and the assessed parameters.
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Hadid, Zoheir. "Gazéification du GNL par cycle de Brayton associé à une boucle caloportrice et une pompe à chaleur." Thesis, Paris, ENMP, 2012. http://www.theses.fr/2012ENMP0112/document.
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Le marché du gaz naturel liquéfié (GNL) est en plein essor et présente l'avantage de diversifier les approvisionnements. Le GNL est acheminé à une température de -162 °C et à pression atmosphérique. L'objet principal de la thèse vise à valoriser l'exergie contenue dans le GNL lors de sa gazéification et de son réchauffage avant d'être distribué sur le réseau. La thèse étudie un nouveau concept de gazéification qui se différentie des développements en cours par l'usage de l'air ambiant comme seule source de chaleur et par la valorisation d'une partie de l'exergie du GNL en énergie mécanique.Une analyse énergétique et exergétique a permis de définir des architectures de cycles moteurs utilisant l'énergie calorifique de l'air comme source chaude (récupérée par un fluide intermédiaire qui est le propane) et le GNL comme puits froid.L'usage de l'air ambiant conduit à gérer les cycles de givrage et dégivrage sur les évaporateurs du fluide intermédiaire récupérant les calories de l'air. Ceci nécessite la compréhension des phénomènes couplés de transferts de chaleur et de masse. Pour cela un banc d'essai a été construit afin de caractériser des échangeurs à ailettes rondes discontinues en condition de givrage et de valider un modèle numérique simulant le comportement de ces échangeurs en présence de givre. Cette modélisation a permis de proposer une logique de dimensionnement et d'exploitation des évaporateurs à air en prenant en compte l'effet du givre. Une étude saisonnière a montré que le procédé proposé est énergétiquement excédentaire tout au long de l'annéeThe market of liquefied natural gas (LNG) is growing and presents the advantage of diversifying supplies. The LNG is fed at a temperature of -162°C and at atmospheric pressure. The main objective of the thesis aims at the valorization of the LNG exergy during its gasification and heating before being delivered through the network. The thesis investigates a new concept of gasification that differs from the current developments by the use of ambient air as the only heat source and by partial valorization of the LNG exergy in mechanical energy.An energy and exergy analysis helped to the definition of engine-cycle architectures using the air heating capacity as a heat source (recovered by an intermediate fluid, here propane) and LNG as a cold sink.The use of ambient air led to manage frosting and defrosting cycles on the evaporators of intermediate fluid recovering heat from the air. This requires understanding the coupled heat and mass-transfer phenomena. A test bench was built to characterize Circular Finned-Tube Heat Exchangers in frosting conditions and to validate a numerical model simulating the behavior of such heat exchangers in presence of frost. As a result, a logic for the design and operation of air heat exchangers is proposed taking into account the frosting effect. A seasonal study showed that the output power generated by the new concept of gasification is superior to its energy consumption throughout the year
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Oluleye, Oluwagbemisola Olarinde. "Integration of waste heat recovery in process sites." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/integration-of-waste-heat-recovery-in-process-sites(ebbc2669-2c9b-40be-9eae-8d2252f0286f).html.
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Exploitation of waste heat could achieve economic and environmental benefits, while at the same time increase energy efficiency in process sites. Diverse commercialised technologies exist to recover useful energy from waste heat. In addition, there are multiple on-site and offsite end-uses of recovered energy. The challenge is to find the optimal mix of technologies and end-uses of recovered energy taking into account the quantity and quality of waste heat sources, interactions with interconnected systems and constraints on capital investment. Explicit models for waste heat recovery technologies that are easily embedded within appropriate process synthesis frameworks are proposed in this work. A novel screening tool is also proposed to guide selection of technology options. The screening tool considers the deviation of the actual performance from the ideal performance of technologies, where the actual performance takes into account irreversibilities due to finite temperature heat transfer. Results from applying the screening tool show that better temperature matching between heat sources and technologies reduces the energy quality degradation during the conversion process. A ranking criterion is also proposed to evaluate end-uses of recovered energy. Applying the ranking criterion shows the use to which energy recovered from waste heat is put determines the economics and potential to reduce CO2 emissions when waste heat recovery is integrated in process sites. This thesis also proposes a novel methodological framework based on graphical and optimization techniques to integrate waste heat recovery into existing process sites. The graphical techniques are shown to provide useful insights into the features of a good solution and assess the potential in industrial waste heat prior to detailed design. The optimization model allows systematic selection and combination of waste heat source streams, selection of technology options, technology working fluids, and exploitation of interactions with interconnected systems. The optimization problem is formulated as a Mixed Integer Linear Program, solved using the branch-and-bound algorithm. The objective is to maximize the economic potential considering capital investment, maintenance costs and operating costs of the selected waste heat recovery technologies. The methodology is applied to industrial case studies. Results indicate that combining waste heat recovery options yield additional increases in efficiency, reductions in CO2 emissions and costs. The case study also demonstrates that significant benefits from waste heat utilization can be achieved when interactions with interconnected systems are considered simultaneously. The thesis shows that the methodology has potential to identify, screen, select and combine waste heat recovery options for process sites. Results suggest that recovery of waste heat can improve the energy security of process sites and global energy security through the conservation of fuel and reduction in CO2 emissions and costs. The methodological framework can inform integration of waste heat recovery in the process industries and formulation of public policies on industrial waste heat utilization.
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Kürthy, Marián. "Kogenerační jednotka s absorpčním TČ." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230314.
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This diploma work aims to evaluate the functional connection of the cogeneration unit with an internal combustion engine and an absorption heat pump to increase the heating effect of the cogeneration. The aim of this work is to design a functional system and evaluate it from the technical - economic terms. In the introduction of the theoretical work the applied cogeneration technologies used in combined heat and power production are presented. Then there is described the principle of heat pumps, their basic components and theoretical comparison of compression and absorption heat pumps. In the practical part of this work is for a specific application in the area Technická 2 proposed merger of the cogeneration unit with an internal combustion engine and an absorption heat pump, while detailed design parameters used in absorption heat circulation are set. At the end of this paper there are designed various heat exchangers of applied absorption heat pump. The final part of the work is devoted to technical - economic assessment of applied design. In this assestment three different types of heat pumps are compared: Absorption heat pump with working solution H2O-LiBR, absorption heat pump with working fluids NH3-H2O and compressor heat pump.
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Dobiáš, Ladislav. "Náhrada stávající výměníkové stanice pára/voda za plynový kotel." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231285.
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In this work, there is an overview of the design concept of condensing boilers and types of heat pumps. The current state of heating in company is assessed and possible variants are given for techno-economic evaluation. For boiler room with the gas boiler is prepared a proposal with condensation boiler. For parameters are designed and calculated proposals to form a condensing boiler. The end of the work is focused on the advantages of gas boiler and heat pump.
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Bednařík, Jakub. "Využití odpadního tepla z technologických procesů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-376930.
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Master thesis deals with the utilization of waste heat from Nova Mosilana company. Theoretical part of this work is focused on the waste heat description (heat, heat quantity, heat temperature/quality, composition of waste stream) in which a considerable energy potential is hidden. The other parts describe waste heat technology, especially heat pumps, Organic Rankine Cycle (ORC) and system absorption cooling. Some of the technologies described in the theoretical part are used in the design of the more efficient existing waste heat utilization, especifically power and cold production.
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Angren, Jimmy, and Joel Arnoldsson. "Fjärrvärmens konkurrenskraft : En analys av olika uppvärmningsteknikers kostnadseffektivitet och kunders beslutsfattande." Thesis, Linköpings universitet, Industriell miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-110010.
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Historiskt sett har den Svenska värmemarknaden dominerats av fjärrvärmen som i princip varit det enda kostnadseffektiva alternativet där det funnits tillgängligt. På senare tid har dock spelreglerna börjat på att förändras, bland annat på grund av värmepumparnas intåg, en förändrad energipolitik och ökade kundkrav – vilket har lett till en mer konkurrensutsatt marknad. Denna studie syftar till att både kvantitativt och kvalitativt analysera fjärrvärmens konkurrenskraft jämfört med alternativa uppvärmningstekniker, med fokus på segmenten flerbostadshus, övriga- samt offentliga lokaler. Efter en inledande marknadsundersökning bedömdes värmepumpar i kombination med el eller fjärrvärme, samt pellets i kombination med RME, kunna vara konkurrenskraftiga med fjärrvärme. Därefter beräknades livscykelkostnaden för dessa värmesystem för en generell fastighet som en funktion av dess energibehov och utnyttjningstid, samt för ett antal typanvändare. Dessa typanvändare identifierades genom att analysera förbrukningsstatistik från Vattenfall. Vidare genomfördes flera intervjuer med branschexperter parallellt med att en enkät sammanställdes som riktade sig till energi- och klimatrådgivare i Sverige. Enkäten syftade till att få en nulägesbeskrivning av fastighetsägares syn på värmemarknaden och på så sätt bidra till den kvalitativa analysdelen. Resultatet visar att det rent kostnadsmässigt är små skillnader mellan fjärrvärme och övriga alternativ givet de antaganden som författarna anser är rimliga. För ett typiskt flerbostadshus är fjärrvärme mer fördelaktigt men för en typisk övrig eller offentlig lokal är bergvärme ett marginellt bättre alternativ. Frånluftsvärmepump med fjärrvärme är i båda fallen en billig lösning. Dock visar känslighetsanalysen att det kan skilja med mer än en faktor 2,5 i livscykelkostnad för samtliga alternativ beroende på vilka antaganden som görs. Således är valet av värmesystem ur fastighetsägarens perspektiv nära kopplat till riskbedömning, vad denne tror om framtiden och vilken relation de har till nuvarande värmeleverantör. För alla fastighetsägare är säker och problemfri drift den viktigaste parametern utöver kostnaden. Det finns även en ovisshet kring framtida prishöjningar av både el- och fjärrvärme, vilket leder till osäkra kalkyler. Därför kan förtroendet och relationen med nuvarande värmeleverantör vara avgörande vid en beslutssituation. En hög investeringskostnad är också en tydlig barriär - parallellt som investeringen ofta konkurrerar med andra energi- och fastighetsåtgärder om samma budget. Miljöfrågan är viktig för offentliga lokaler och kan vara det även för övriga lokaler, men är sällan av stor betydelse för flerbostadshus. Sammanfattningsvis är det svårt att avgöra vilket alternativ som är mest konkurrenskraftigt i dagsläget. Flera faktorer spelar in och livscykelkostnaden kan variera kraftigt mellan bästa och sämsta fall för uppvärmningsalternativen. Emellertid indikerar denna studie att en effektbaserad prismodell leder till att fjärrvärmen stärker sin konkurrenssituation bland flerbostadshus men blir mer utsatt i segmenten offentliga respektive övriga lokaler. Särskilt i det senare är bergvärmepumpar ett växande hot. För att bibehålla sin konkurrenskraft är det viktigt att fjärrvärmeleverantörerna är transparenta och tydliga i kommunikationen mot sina kunder, framförallt när det gäller prisutvecklingen. På sikt kan affärsmodellen och erbjudandet behöva innafatta mer än bara värmeleveransen, exempelvis stöd vid energieffektivisering, miljöcertifierad värme samt ett komforterbjudande.Historically, the Swedish heat market has been dominated by district heating, which basically has been the only cost effective option where it’s available. Lately, however, the situation has begun to change, partly because of the increased efficiency of heat pumps, but also due to changes in energy policies and increased customer demands - which has led to a more competitive heating market. This study aims to quantitatively and qualitatively analyze the competitiveness of district heating compared to alternative heating technologies, focusing on three segments; apartment buildings, public facilities and other premises. After an initial market analysis, heat pumps in combination with electricity or district heating as peak load, as well as pellets in combination with RME, were identified as the most competitive alternatives to district heating. The estimated life cycle cost of the heating systems was then calculated for a number of facilities, as a function of its energy needs and utilization time. These facilities were chosen based on consumption statistics from Vattenfall. Furthermore, several interviews with industry experts were conducted, in parallel with an inquiry that was addressed to energy and climate advisers in Sweden. The survey aimed to get an up-to-date status report of property owners' views on the heat market and thus contribute to the qualitative analysis. The result shows, given the assumptions that the authors find reasonable, that there are minor differences between district heating and its competition if viewed from a cost perspective only. For a typical apartment building, district heating is slightly more beneficial, but for a typical public facility/other premise geothermal heat is a marginally cheaper option. Exhaust air heat pump with district heating as peak load is in both cases a cost effective option. However, the sensitivity analysis shows that the life cycle cost can differ by more than a factor of 2,5 for all heating systems depending on what assumptions are made. Hence, the choice of heating system is from the property owner's perspective closely related to perceived risk and the extent to which trust towards the heat supplier exists. Effortless and reliable operations appear to be the most important factor besides costs for all customer types. Also, there is uncertainity about future price development among all segments, which can lead to impaired calculations. Thus, the customers’ trust for the existing heat distributor, as well as the relationship between them, may fundamentally affect the choice of heating system. A high investment cost is a crucial barrier since it carries a higher risk while also competing with other efficiency measures about the same budget. Public facility owners are keen about the environmental aspects while this question is of less importance for apartment buildings owners. It may be of importance for other premise owners depending on the owner. In summary, it’s difficult to determine the most competitive heating system since the cost effectiveness for all heating systems can vary a lot depending on the assumptions. However, this study indicates that a power based price model will strengthen the competitiveness for district heating among apartment buildings. Among public facilities and other premises it will become more vulnerable to other heating technologies, especially to geological heat pumps. To stay competitive it’s important for district heating distributors to be transparent and clear in the communication with their customers, particularly in regards of price development. In the long term it may be necessary to include more than district heating in their offer, for example support in energy efficiency measures, an environmentally certified heat supply or an offer of guaranteed indoor- comfort.
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Wernqvist, Jonas, and Kalle Cedervall. "Jämförelse av central och lokal uppvärmning av mindre bostadsrättsförening." Thesis, KTH, Byggteknik och design, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215429.
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Idag när bostadsmarknaden växer snabbare än på länge blir samtidigt energihushållning viktigare och viktigare. Ekonomiska och miljömässiga intressen från bostadsägare angående stigande elpriser och energihushållning leder båda till ett mer medvetet byggande vad gäller klimatskalets täthet, energismarta installationer såsom styrda FTX-system och andra besparingsåtgärder.Examensarbetet har skrivits åt Bjerking för att undersöka möjligheten till att centralisera uppvärmningen istället för att värma upp bostäderna med varsin frånluftsvärmepump i en bostadsrättsförening bestående av parhus.Rapporten innehåller en del beräkningar i form av energiförluster och kostnadsberäkningar för de olika värmesystemen samt statistik för uppvärmning i Sverige.Examensarbetet har resulterat i kostnadsberäkningar som kan användas vid inledande investeringsberäkning för centraliserad uppvärmning i liknande projekt.Today, when the housing industry is growing faster than in a long time energy house holding is becoming more important for every day. Economic and environmental interests from house owners, when it comes to increasing energy prices and energy house holding, both leads to a more conscious house building. This includes the buildings U-value, energy smart installations and other energy saving arrangements.This examination paper has been written for Bjerking to investigate the possibility to centralize the heating in a housing society of several semi-detached houses instead of heating them locally with the standard solution, an exhaust air heat pump per apartment.This examination paper includes a few calculations of energy losses and life cycle costs for the different heating systems. It also includes a bit of statistic for different types of heating in Sweden.It has ended in cost calculations that can be used when thinking about and planning to build semi-detached houses with central heating.
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Desrues, Tristan. "Stockage massif d'électricité sous forme thermique." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00627054.
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Les travaux présentés dans cette thèse concernent un nouveau procédé de stockage d'électricité à échelle industrielle, sous forme de stockage de chaleur sensible. La chaleur est stockée dans deux échangeurs gaz-solide de grande taille appelés régénérateurs qui sont reliés à une paire de turbomachines (compresseur et turbine) formant ainsi un cycle thermodynamique. Selon le sens d'écoulement du fluide caloporteur, ce cycle est de type " pompe à chaleur " en stockage ou " moteur thermique " en déstockage. La modélisation complète du procédé a permis de caractériser son comportement dans un cas industriel, et de mettre en évidence les tendances principales du système. Les performances prévues se rapprochent de celles des installations existantes les plus adaptées au stockage massif d'électricité, telles que le stockage hydraulique gravitaire. Une étude CFD a permis l'optimisation d'une géométrie de canal à obstacles destinée à intensifier l'échange thermique dans les régénérateurs et qui sera testée expérimentalement à la suite de cette thèse. Les préparatifs de cette expérience sont abordés et ses objectifs sont explicités.
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Спориш, О. О. "Дослідження термокомпресійної теплонасосної установки реалізованої за циклом Чистякова-Плотнікова." Master's thesis, Сумський державний університет, 2018. http://essuir.sumdu.edu.ua/handle/123456789/72242.
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У роботі досліджено термокомпресійну теплонасосну установку реалізованої за циклом Чистякова-Плотнікова.В работе исследованы термокомпресийну теплонасосной установки реализованной по циклу Чистякова-Плотникова.
In this work, the thermocompressor of a heat pump unit realized in the Chistyakov-Plotnikov cycle was investigated.
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Besbes, Karim. "Pompes à chaleur à haute température récupérant la chaleur sur des buées ou de la vapeur d'eau à moyenne température." Thesis, Paris, ENMP, 2015. http://www.theses.fr/2015ENMP0091/document.
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La pompe à chaleur industrielle très haute température (PAC THT) à compression mécanique de vapeur, fonctionnant à l'électricité, figure parmi l'une des technologies innovantes les plus efficaces permettant de valoriser les rejets thermiques industriels à basse et moyenne température (<90 °C). Néanmoins, compte tenu des besoins industriels actuels de chaleur, les niveaux de température cible atteignable par les PACs restent trop faibles et freinent fortement son implantation. Les procédés de séchage, dans leur grande majorité, rejettent des buées ou de la vapeur d'eau à moyenne température (50 °C-90 °C) et ont des besoins de chaleur à très haute température (110 °C-150 °C). Le grand écart de température entre la source et le besoin de chaleur ainsi que le niveau de température du besoin, font qu'aujourd'hui envisager l'intégration d'une PAC dans ce type de procédés relève d'un défi énergétique et technologique particulièrement intéressant, dont l'enjeu économique est considérable. Les présents travaux de recherche envisagent à l'aide d'une méthodologie générique d'optimisation de cycles thermodynamiques basée sur la minimisation de la production d'entropie dans les échangeurs de chaleur de déceler les architectures de PACs les plus efficaces d'un point de vue énergétique. L'analyse théorique a permis de déceler la haute efficacité énergétique des architectures transcritiques de PACs dans des conditions de grands glissements de température entre l'entrée et la sortie du besoin de chaleur. Le développement d'un démonstrateur de PAC transcritique très haute température fonctionnant au R32 (PAC T-THT R32) a permis d'une part de démontrer la faisabilité technique d'une PAC, pouvant atteindre la température cible de 120 °C en partant de 60 °C avec une source de chaleur disponible à 50 °C, et d'autres part de démontrer sa haute efficacité énergétique (COP = 4)The mechanical vapour compression high temperature heat pump for industry using electricity is one of the most effective innovative technologies to recover the industrial waste heat at low and medium temperature (<90°C). However, given the current industrial heat needs, the heat pump target temperature levels remain too low and slow strongly its implantation. Overwhelmingly, the drying processes reject saturated moist air at middle temperature (50°C-90°C) and have heat needs at very high temperature (110°C-150°C). The large temperature difference between the source and the heat need and the level off temperature that is needed, today, makes the heat pump integration in such processes an interesting energy and technological challenge, whose economic stake is considerable. The present works tackle, with a generic methodology of thermodynamic optimisation cycles based on the entropy minimization in the heat exchangers, to identify the most efficiency heat pump architectures from an energy point of view. The theoretical analysis allowed to detect the transcritical heat pump architecture, in conditions of high temperature glides between the inlet and the outlet of the heat need. The development of a transcritical high temperature heat pump demonstrator using the R32 as working fluid allowed to demonstrate the technical feasibility of a heat pump that can reach the target temperature of 120°C from 60°C with an available heat source at 50°C, and to demonstrate its high energy efficiency (COP = 4)
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Снісаренко, Д. О. "Дослідження теплонасосної установки системи опалення на базі рідинно-парового ежектора з робочим середовищем R718." Master's thesis, Сумський державний університет, 2021. https://essuir.sumdu.edu.ua/handle/123456789/86613.
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У роботі виконано розрахунок теплового навантаження приміщення та визначено величину тепловтрат в залежності від температури навколишнього середовища. Виконано термодинамічний, ексергетичний та термоекономічний розрахунок теплонасосної установки для потреб опалення з робочим середовищем R718 на базі рідинно-парового ежектора в складі вакуумного агрегату та виконано порівняльний аналіз з традиційними теплонасосними установками з робочими середовищами R142b, R245fa та R410a. В результаті цього визначено доцільність впровадження нової установки. У розділі охорони праці виконано аналіз шкідливих та небезпечних факторів при експлуатації опалювального обладнання та виконано розрахунок захисного заземлення електричного обладнання.В работе выполнен расчет тепловой нагрузки помещения и определена величина теплопотерь в зависимости от температуры окружающей среды. Выполнен термодинамический, эксергетический и термоэкономический расчет теплонасосной установки для нужд отопления с рабочей средой R718 на базе жидкопарного эжектора в составе вакуумного агрегата и выполнен сравнительный анализ с традиционными теплонасосными установками с рабочими средами R142b, R245fa и R410a. В результате определена целесообразность внедрения новой установки. В разделе охраны труда выполнен анализ вредных и опасных факторов при эксплуатации отопительного оборудования и расчет защитного заземления электрического оборудования.
In this work, the calculation of the heat load of the room was carried out and the amount of heat loss was determined depending on the ambient temperature. A thermodynamic, exergy and thermoeconomic calculation of a heat pump unit for heating needs with a working medium R718 based on a liquid-vapor ejector as part of a vacuum unit was carried out and a comparative analysis was performed with traditional heat pump units with working environments R142b, R245fa and R410a. As a result, the expediency of introducing a new installation was determined. In the labor protection section, an analysis of harmful and dangerous factors during the operation of heating equipment and the calculation of protective grounding of electrical equipment is carried out.
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Mantilla, Gutierrez Weimar. "Towards Flexible Power Generation Short-term Optimization of a Combined Cycle Power Plant Integrated with an Inlet Air Conditioning Unit." Thesis, KTH, Energiteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263904.
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Combined cycle gas turbine power plants (CCGT), as part of the electricity generation fleet, are required to improve their flexibility to help balance the power system under new scenarios with high shares of variable renewable sources. Among the different possibilities to enhance the power plant performance, an inlet air conditioning unit offers the benefit of power augmentation and “minimum environmental load” reduction by controlling the gas turbine intake temperature using cold thermal energy storage and a heat pump. In this thesis, an evaluation of the conditioning unit impact over a power-oriented CCGT under a day-ahead optimized operation strategy is presented. To establish the hourly dispatch of the power plant and the right operation mode of the inlet condition unit bringing the desired benefits, a mixed-integer linear optimization was formulated aiming to maximize the operational profit of the plant within a 24 hours horizon. To assess the impact of the proposed unit operating under this control strategy, annual simulations of a reference power plant were developed with and without the unit, allowing to a comparison of their performance by means of technical and economic indicators. Furthermore, a case study changing equipment sizes was performed in order to identify trends of the power plant performance related to such parameters; and lastly, a sensitivity analysis on market conditions to test the control strategy response was included. The results indicate that the inlet conditioning unit together with the dispatch optimization increase the power plant operational profit trough the gain of power variation over peak and off-peak periods. For the specific case study in northern Italy, it is shown that a power plant integrated with the conditioning unit is more profitable in terms of net present value based on the undertaken investment figures. Related to the technical performance, it also shows that the unit reduces by 1,34% the minimal environmental load when part-load operations are required and that it can increase the net power output by 0.17% annually. All in all, this study presents the benefits of a dispatch optimization strategy when couple to a novel solution to increase CCGT flexibility.Elproducerande kombikraftverk (CCGT) förväntas förbättra sin flexibilitet för att kunna bidra till stabilisering av elnätet i framtida scenarier med ökande andel variabla, förnybara energikällor. Av de diverse metoder som finns att tillgå för att förbättra ett kraftverks prestanda, erbjuder en inluftsbehandlingsenhet både fördelar med kraftförbättring samt minskning av “minimun environmental load”; genom att med hjälp av kall termisk energilagring och en värmepump kontrollera gasens inluftstemperatur till gasturbinen. I den här uppsatsen undersöks hur en sådan inluftsbehandlingsenhet påverkar prestandan hos en kraftproduktionsfokuserad CCGT när en optimerad driftsstrategi introduceras. För att bestämma kraftverkets elproduktion vid varje timme och det korrekta driftläget för luftbehandlingsenheten (för att uppnå tidigare nämnda eftersökta fördelar) formulerades ett linjärt optimeringsproblem med syfte att maximera kraftverkets driftsförtjänst under ett 24-timmars tidsspann. För att bedöma den föreslagna inluftsbehandlingsenhetens inverkan under den optimerade driftsstrategin genomfördes simuleringar av ett referenskraftverk med och utan nämnda enhet, varpå en jämförelse med avseende på teknisk prestanda och ekonomi genomfördes. Vidare genomfördes en fallstudie där storlek på diverse utrustning varierades för att kunna identifiera trender i kraftverksprestanda baserat på dessa parametrar; slutligen genomfördes en känslighetsanalys rörande hur luftbehandlingsenheten och kontrollstrategin reagerar vid olika marknader.. Resultaten indikerar att en inluftsbehandlingsenhet tillsammans med en optimerad driftsstrategi ökar kraftverkets driftsvinning genom en ökad variation i kraftuttag över peak och off-peak timmar. För fallstudien i norra Italien fanns att ett kraftverk med integrerad luftbehandlingsenhet är mer lönsamt sett till nuvärdesanalys. Gällande teknisk prestanda visade resultaten att enheten minskar den minsta miljöbelastningen med 1,34 % när delbelastningsdrift fordras, och att det kan öka nettokraftuttag med 0,17% årligen. Sammanfattningsvis presenterar denna studie fördelarna med ett driftsoptimerat kraftverk kopplat till en ny lösning för att öka flexibilitet hos CCGT:er.
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Niznik, Maria. "Amélioration et intégration d'une méthode d'affichage des performances en temps réel d'une pompe à chaleur." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM029/document.
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Actuellement, la plupart des fabricants de pompes à chaleur (PAC) fournissent les valeurs de coefficients de performances (COP) obtenus en laboratoire en conditions contrôlées et standardisées. Une méthode prometteuse, appelée méthode de mesure des performances dans la suite, d’évaluation des performances de PAC in situ, basée sur le bilan énergétique du compresseur, a été présentée par Tran et al. (2013). Cette méthode détermine le débit de fluide frigorigène et est compatible avec différents types de PAC, notamment air-air, et des cycles frigorifiques plus complexes.Tran et al. (2013) ont déterminé que l’incertitude sur l’évaluation de pertes thermiques du compresseur contribue à hauteur de 40% sur l’erreur d’estimation de la puissance thermique. L’objectif de cette thèse est d’établir une méthode simplifiée quant à l’instrumentation pour mesurer les pertes thermiques in situ. Pour cela, deux modèles numériques détaillés sont développés afin d’examiner la distribution de température sur l’enveloppe de deux types de compresseurs, scroll et rotary. Les mesures expérimentales fournies par un fabricant de compresseurs, Mitsubishi Heavy Industries (MHI), sont utilisées pour calibrer et valider les modèles numériques. Ces derniers permettent de définir deux protocoles de mesures différents pour les deux compresseurs. Ensuite, le protocole établi pour le compresseur rotary est intégré dans la méthode de mesures des performances. Les puissances thermiques calculées sont comparées avec des valeurs de référence, obtenues à partir d’un prototype en banc d’essai à EDF Lab Les RenardièresCurrently, most heat pump(HP) manufacturers provide coefficient of performance (COP) values obtained in laboratories under standardized controlled operating conditions. These COP values are not necessarily representative of those obtained on-field. A promising method, referred to as the performance assessment method, that measures heat pump performances in-situ based on compressor energy balance, was presented by Tran et al. (2013). The method determines refrigerant mass flow rate and has the capability of measuring performances of various HP types, such as air-to-air, as well as more complex refrigeration cycles. The method abstains from intrusive measurements, and is, therefore, perfectly suitable for in-situ measurements.As shown in the work of Tran et al. (2013), compressor heat losses account for 40% in the final uncertainty of performance values obtained with the performance assessment method. The objective of this thesis is to establish a rather simplified measurement method, in terms of instrumentation, that is used to determine compressor heat losses in-situ. For this purpose two detailed numerical models for assessing the temperature fields of the scroll and rotary compressor shells were developed. Experimental measurements obtained with the help of compressor manufacturer, Mitsubishi Heavy Industries (MHI), are used to validate and calibrate the numerical models. The developed numerical models allow to define two different measurement protocols for both compressors. Established compressor heat loss protocol for rotary compressor is then integrated in the performance assessment method and the obtained heating capacities are compared with reference measurements in an experimental test bench in EDF Lab Les Renardières
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Івахно, Г. Г. "Оцінка впливу режимних параметрів первинного контуру теплонасосної установки на її енергоефективність." Master's thesis, Сумський державний університет, 2021. https://essuir.sumdu.edu.ua/handle/123456789/86610.
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У роботі виконано варіантні розрахунки для теплонасосної установки з первинним контуром роздільного та суміщеного виконання в залежності від температури навколишнього середовища. В результаті розрахунків одержано залежності навантаження на випарник, зміну коефіцієнта перетворення холодильного циклу та споживану потужність компресора. У розділі охорони праці виконано аналіз шкідливих та небезпечних факторів при експлуатації теплонасосного обладнання та виконано розрахунок природного та штучного освітлення ділянки цеху, в якому експлуатується дана теплонасосна установка.В работе выполнены вариантные расчеты для теплонасосной установки с первичным контуром раздельного и совмещенного исполнения в зависимости от температуры окружающей среды. В результате расчетов получены зависимости нагрузки на испаритель, изменение коэффициента преобразования холодильного цикла и потребляемая мощность компрессора. В разделе охраны труда выполнен анализ вредных и опасных факторов при эксплуатации теплонасосного оборудования и расчет природного и искусственного освещения участка цеха, в котором эксплуатируется данная теплонасосная установка.
In this work, variant calculations have been made for a heat pump installation with a primary circuit of separate and combined versions, depending on the ambient temperature. As a result of calculations, the dependences of the load on the evaporator, the change in the conversion factor of the refrigeration cycle and the power consumption of the compressor were obtained. In the labor protection section, the analysis of harmful and dangerous factors during the operation of heat pump equipment and the calculation of natural and artificial lighting of the section of the workshop in which this heat pump unit is operated is carried out.
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Kotásek, Petr. "Systémy přímého chlazení v potravinářských provozech." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240239.
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Diploma thesis deals with direct cooling systems in food processing plants. The work focuses on the description of the components of the refrigerant cycle, with emphasis on the choice of refrigerant. The result is a design of direct cooling system in the food factory in the variants with refrigerant R404A and R717. The work describes the advantages and disadvantages of various options. The work includes an experimental section which deals with the measure-ment and processing of the actual values of the refrigerant cycle and the comparison of two cold sources.
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Maxamhud, Mahamed, and Arkam Shanshal. "SELF-SUFFICIENT OFF-GRID ENERGY SYSTEM FOR A ROWHOUSE USING PHOTOVOLTAIC PANELS COMBINED WITH HYDROGEN SYSTEM : Master thesis in energy system." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-49379.
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It is known that Sweden is categorised by being one of the regions that experience low solar radiation because it is located in the northern hemisphere that has a low potential of solar radiation during the colder seasons. The government of Sweden aim to promote a more sustainable future by applying more renewable initiative in the energy sector. One of the initiatives is by applying more renewable energy where PV panels will play a greater role in our society and in the energy sector. However, the produced energy from the PV panels is unpredictable due to changes in radiation throughout the day. One great way to tackle this issue is by combining PV panels with different energy storage system. This thesis evaluates an off-grid rowhouse in Eskilstuna Sweden where the PV panels are combined with a heat pump, thermal storage tank, including batteries and hydrogen system. The yearly electrical demand is met by utilizing PV panels, battery system for short term usage and hydrogen system for long-term usage during the colder seasons. The yearly thermal demand is met by the thermal storage tank. The thermal storage tank is charged by heat losses from the hydrogen system and thermal energy from heat pump.The calculations were simulated in Excel and MATLAB where OPTI-CE is composed with different components in the energy system. Furthermore, the off-grid household was evaluated from an economic outlook with respect to today’s market including the potential price decrease in 2030.The results indicated that the selected household is technically practicable to produce enough energy. The PV panels produces 13 560 kWh annually where the total electrical demand reaches 6 125 kWh yearly (including required electricity for the heat pump). The annual energy demand in terms of electricity and thermal heat reaches 12 500 kWh which is covered by the simulated energy system. The overproduction is stored in the batteries and hydrogen storage for later use. The back-up diesel generator does not need to operate, indicating that energy system supplies enough energy for the off-grid household. The thermal storage tank stores enough thermal energy regarding to the thermal load and stores most of the heat during the summer when there are high heat losses due to the charge of the hydrogen system. The simulated energy system has a life cycle cost reaching approximately k$318 with a total lifetime of 25 years. A similar off-grid system has the potential to reduce the life cycle cost to k$195 if the energy system is built in 2030 with a similar lifespan. The reduction occurs due to the potential price reduction for different components utilized in the energy system.
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Liou, shu hong, and 劉書宏. "Life Cycle Assessment of Heat Pump-Considerations of Heat Source and Heat Sink." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/44646227381996300592.
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碩士國立臺北大學
自然資源與環境管理研究所
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Taiwan depended on fossil fuel as its main using energy for a long time, resulting the Greenhouse gases remained a huge number, and the regeneration cycle of fossil fuel was very long time, almost could as it was a non-renewable energy, so there is a problem how should we reduce the demand of fossil fuel, and developing the appropriate energy of natural resource will be a important step of sustainability with Taiwan. This research’s target referenced the energy using statistics value of real exist building, calculated the target’s carrying capacity of air conditioning and hot water, there are seven cases in research, the case 1 is target’s original statistics value, the other are scenarios, the result of the case 2(all the air condition get exchanged with GSHPs)have the best performance with the energy input, reduction of CO2 emission and the energy costs in using phase, Otherwise the case 3 is the worst in every scenarios, but comparing with the case 1, it’s still has a nice performance and advantage, but the CO2 emission is more than the case 1. To compare with the case 1, the ranges of reduction of energy input in using phase is between 69,747~123,082GJ; the ranges of reduction of CO2 emission in using phase is between 2,429~11,662Mt, the ranges of energy costs in using phase is between 52~86M. The Payment of energy with the case 2, case 2a and case 2b are 0.11y, 0.10y, 0.16y; The Payment of CO2 emission are 0.08y, 0.10y, 0.12y.
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Van, Eldik Martin. "Simulation of a micro heat pump cycle / Martin van Eldik." Thesis, 1998. http://hdl.handle.net/10394/16071.
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The purpose of this study was to develop a thermal cycle simulation for a micro heat pump. A feature of the simulation is that it can simulate the four qasic components in detail, based on fundamental principles. The product of this study is a simulation routine which can be used as a design tool for micro heat pumps as well as its individual components. Experimental tests were conducted on an existing R-134a micro heat pump.and the results were successfully used to verify the simulation routines. An extensive literature survey was conducted on heat pump component models as well as heat transfer correlations. In this study models were developed for each of the four basic components used in the micro heat pump, i.e. fluted tube water heating condenser, air-cooled evaporator, reciprocating compressor and capillary tube. The theory on which each model is based, was derived from first principles and the relevant model algorithms were developed and implemented in C++ computer routines. The component models were also integrated to allow a complete cycle simulation at different operating conditions. An advantage of the fluted tube condenser model is that it allows the surface area to be divided into any number of sections over which the change in refrigerant and water properties can be evaluated. The evaporator model calculates the change in refrigerant properties along the length of each tube in the coil. It can also predict in detail the state of the air across the coil face and along the depth of the coil. A model for simulating the compressor was derived which solves for both the mass flow rate and the refrigerant outlet conditions. Two capillary tube models were implemented. The first was based on a theoretical model obtained in the literature. This model did not provide sufficiently accurate results, however the second capillary tube model was based on a dimensional analysis providing a non-dimensional correlation for the mass flow rate. The coefficients of the correlation had to be modified for this application. The individual component models as well as the integrated cycle were both verified by means of the experimental data. The verification study showed that for the integrated cycle the condenser and evaporator heat transfer rates were predicted with average accuracies of 97% and 96% respectively. The refrigerant mass flow rates predicted by the compressor and the capillary tube models resulted in an average accuracy of 95%.
The high degree of accuracy obtained with the individual models as well as with the integrated cycle provides confidence in the simulation results. The simulation can therefore be applied as a design tool for micro heat pumps and its individual components.Thesis (MIng)--PU for CHE, 1999
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Self, Stuart. "Enhancing geothermal heat pump systems with parametric performance analyses." Thesis, 2010. http://hdl.handle.net/10155/93.
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Parametric performance analyses and comparison of a basic geothermal heat pump, a heat pump cycle with motor cooling/refrigerant preheating, and a heat pump cycle utilizing an economizer with respect to first law is conducted through simulation. Changing compressor, pump, and motor efficiency, along with condenser pressure, evaporator pressure, degree of subcooling at the condenser exit and degree of superheating at the evaporator exit is investigated. Economizer arrangements yield the highest coefficient of performance and resilience to change in COP with variation in evaporator pressure, and degree of superheating and subcooling. The basic vapor compression and motor cooling/refrigerant preheating systems have the lowest COP throughout and greatest resilience to variation in compressor efficiency, motor efficiency and condenser pressure. Motor cooling/refrigerant preheating and economizers have advantages over basic vapor compression cycles. Motor cooling reduces ground loop heat exchanger length with similar COP, and economizers allow for an increase in COP compared to the basic cycle.UOIT
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Diogo, João Bernardo Cabral de Mascarenhas. "Preliminary assessment of carnot batteries as an innovative electrical energy storage." Master's thesis, 2021. http://hdl.handle.net/10316/97950.
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Dissertação de Mestrado Integrado em Engenharia Mecânica apresentada à Faculdade de Ciências e TecnologiaIncreased world-wide demand for energy (especially electricity), rising energy costs, and heightened environmental concerns are factors that continually press for the adoption of technologies to exploit the renewable energy sources (RES). However, due to the ever increasing share of RES in the energy mix, large-scale energy storage systems are considered essential to ensure the security of supply in energy systems.The purpose of this work arises from the need to find a new form of energy storage technology, which works without any restriction of location, with low-cost materials and a high storage capacity. The technology studied comprehends a combination of a heat pump that transforms electrical energy into thermal energy in the charge phase, that can be stored for several hours to a few days, and an organic Rankine cycle (ORC) that transforms the thermal stored energy in electrical energy again in the discharge situation. This technology is known as Carnot BatteriesThree different configurations of the Carnot Batteries were tested using models created in Matlab programming software. The first model is a simple model in which both the heat pump and the organic Rankine cycle are described in the simplest configuration. The second model adds a new stage in the heat pump and an organic Rankine's cycle regenerator. The third and last model uses an additional heat source (waste heat, geothermal or solar) to the cycle.Six working fluids were used to run the tests in the three configurations, R1233zd(E), R1234yf, R11, R236ea, R245fa, and iso-pentane. The second configuration makes the system more complex but increases the P2P efficiency relatively to the first one. The third configuration achieves P2P efficiencies higher than 100%, where the resulting electrical energy of the system is bigger than the provided one. The best results were obtained using the third configuration with iso-pentane as the working fluid.
O aumento da demanda mundial por energia (especialmente eletricidade), os custos crescentes da energia e as preocupações ambientais intensificadas são fatores que pressionam continuamente para a adoção de tecnologias para explorar as fontes de energia renováveis (FER). No entanto, devido à participação cada vez maior de FER no cabaz energético, os sistemas de armazenamento de energia em grande escala são considerados essenciais para garantir a segurança do abastecimento dos sistemas energéticos.O objetivo deste trabalho surge da necessidade de encontrar uma nova forma de tecnologia de armazenamento de energia, que funcione sem qualquer restrição de localização, com materiais de baixo custo e elevada capacidade de armazenamento. A tecnologia estudada compreende a combinação de uma bomba de calor que transforma energia elétrica em energia térmica na fase de carga, que pode ser armazenada por várias horas a alguns dias, e um ciclo Rankine orgânico (ORC) que transforma a energia térmica armazenada em elétrica energia novamente na situação de descarga. Esta tecnologia é conhecida como Baterias CarnotTrês configurações diferentes das baterias Carnot foram testadas usando modelos criados no software de programação Matlab. O primeiro modelo é um modelo simples no qual a bomba de calor e o ciclo Rankine orgânico são descritos na configuração mais simples. O segundo modelo adiciona um novo estágio na bomba de calor e um regenerador de ciclo orgânico de Rankine. O terceiro e último modelo usa uma fonte de calor adicional (calor residual, geotérmico ou solar) para o ciclo.Seis fluidos de trabalho foram usados para executar os testes nas três configurações, R1233zd (E), R1234yf, R11, R236ea, R245fa e iso-pentano. A segunda configuração torna o sistema mais complexo, mas aumenta a eficiência P2P em relação à primeira. A terceira configuração atinge eficiências P2P superiores a 100%, onde a energia elétrica resultante do sistema é maior que a fornecida. Os melhores resultados foram obtidos usando a terceira configuração com iso-pentano como fluido de trabalho.