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Delano, Andrew Douglas. "Analysis of the Einstein refrigeration cycle." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/17887.
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Delano, Andrew D. "Design analysis of the Einstein refrigeration cycle." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/17578.
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Wilson, Kyle B. "The use of Sage simulation software in the design and testing of Sunpower's pulse tube cryocooler." Ohio : Ohio University, 2005. http://www.ohiolink.edu/etd/view.cgi?ohiou1126908659.
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Altenhof, Jeffrey L. "Computer-aided concurrent engineering in refrigeration system design." Master's thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-01262010-020010/.
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Menegay, Peter. "Experimental investigation of an ejector as a refrigerant expansion engine." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10222009-124957/.
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Mirza-Tolouee, Changiz M. "Experimental study of zeotropic refrigerant mixture HFC-407C as a replacement for HCFC-22 in refrigeration and air-conditioning systems." Australasian Digital Thesis Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20070416.141307/index.html.
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Thesis (PhD) - Swinburne University of Technology, Faculty of Engineering and Industrial Sciences, 2006.A thesis submitted for the degree of Doctor of Philosophy, School of Engineering and Science, Swinburne University of Technology, 2006. Typescript. Includes bibliographical references (p. 123-127).
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Lough, Benjamin C. C. "Investigations into thermionic cooling for domestic refrigeration." School of Engineering Physics - Faculty of Engineering, 2004. http://ro.uow.edu.au/theses/230.
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Thermionic refrigeration using semiconductor heterostructures is examined theoretically and experimentally. A theory of single-barrier devices is first developed where two classes of single-barrier devices are defined and compared. So-called class 1 devices are found to always perform better. A theory of multiple-barrier devices based on class 1 barriers is then developed using a numerical solution. Experimentally, three generations of 10-barrier devices based on A1(subscript x)Ga(subscript 1-x)As-GaAs heterostructures were made and electrically characterised. This material is by no means ideal (as will be discussed) but was used to availability and because, at the commencement of this work, had never been used for this purpose before. Thermal measurements were made to determine if any cooling occurred at room temperature. No cooling was observed but the electrical characteristics allowed for examination of the models developed. It was found that the earlier models used did not accurately model the I-V characteristics of the devices. This was attributed to the fact that the initial models did not take space-charge into account. A more robust numerical model is developed in which the I-V characteristics of devices are predicted much more accurately. This model is then used to design new generations of devices. The work concludes by recommending a next generation design in which substantially more cooling is expected compared to the samples examined here. The probability of cooling being observed in the future is therefore increased. The types of devices described here will always be hindered because of heat conduction. Other methods incorporating thermionic emission, such as an opto-thermionic system in which removed heat is given off as light, may ultimately prove to be the best solution. This aside, it is hoped that the work presented here will contribute to the understanding of the field.
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O'Loughlin, R. L. "Optimal design of organic refrigerant reverse cycle absorption air conditioning systems /." Title page, contents and abstract only, 1986. http://web4.library.adelaide.edu.au/theses/09ENS/09enso52.pdf.
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Herman, David Laurence. "Experimental optimization of cooling tower fan control based on field data." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/16629.
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Weber, Eric Dean. "Modeling and general optimization of commercial building chiller/cooling tower systems." Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/16874.
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Li, Yong, and 李勇. "Performance prediction model for a rotary multi-bed adsorption coolingsystem." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31245742.
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Kharazi, Amir Ahmadzadeh. "Study of a novel R718 turbocompression cycle." Diss., Connect to online resource - MSU authorized users, 2006.
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Thesis (Ph. D.)--Michigan State University. Dept. of Mechanical Engineering, 2006.Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographic references (p. 84-89). Also issued in print.
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Al-Ansary, Hany A. M. "Investigation and improvement of ejector-driven heating and refrigeration systems." Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-06072004-131032/unrestricted/al-ansary%5Fhany%5Fa%5Fm%5F200405%5Fphd.pdf.
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Mavalankar, Aquila Mukund. "Thermometry and refrigeration using quantum dots." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708092.
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Riley, Caryn M. "Current-based sensorless vibration monitoring of small ac machines." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/13741.
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Moorehead, Lynnette Ann. "Design optimization of cooling tower systems for dual-stage absorption chillers." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/16360.
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Gowreesan, Vamadevan. "Process-structure-property relationship of micro-channel tube for CO₂ climate control systems." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1107891543.
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Walters, Joseph D. "Optimization and Thermodynamic Performance Measures of a Class of Finite Time Thermodynamic Cycles." PDXScholar, 1990. https://pdxscholar.library.pdx.edu/open_access_etds/1186.
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Modifications to the quasistatic Carnot cycle are developed in order to formulate improved theoretical bounds on the thermal efficiency of certain refrigeration cycles that produce finite cooling power. The modified refrigeration cycle is based on the idealized endoreversible finite time cycle. Two of the four cycle branches are reversible adiabats, and the other two are the high and low temperature branches along which finite heat fluxes couple the refrigeration cycle with external heat reservoirs.
This finite time model has been used to obtain the following results: First, the performance of a finite time Carnot refrigeration cycle (FTCRC) is examined. In the special case of equal heat transfer coefficients along heat transfer branches, it is found that by optimizing the FTCRC to maximize thermal efficiency and then evaluating the efficiency at peak cooling power, a new bound on the thermal efficiency of certain refrigeration cycles is given by $\epsilon\sb{m} = (\tilde\tau\sp2\sb{m}\ (T\sb{H}/T\sb{L}) - 1)\sp{-1},$ where $T\sb{H}$ and $T\sb{L}$ are the absolute high and low temperatures of the heat reservoirs, respectively, and $\tilde\tau\sb{m}=\sqrt{2}$ + 1 $\simeq$ 2.41 is the dimensionless cycle period at maximum cooling power.
Second, a finite time refrigeration cycle (FTRC) is optimized to obtain four distinct optimal cycling modes that maximize efficiency and cooling power, and minimize power consumption and irreversible entropy production. It is found that to first order in cycling frequency and in the special symmetric case, the maximum efficiency and minimum irreversible entropy production modes are equally efficient. Additionally, simple analytic expressions are obtained for efficiencies at maximum cooling power within each optimal mode. Under certain limiting conditions the bounding efficiency at maximum cooling power shown above is obtained.
Third, the problem of imperfect heat switches linking the working fluid of an FTRC to external heat reservoirs is studied. The maximum efficiency cycling mode is obtained by numerically optimizing the FTRC. Two distinct optimum cycling conditions exist: (1) operation at the global maximum in efficiency, and (2) operation at the frequency of maximum cooling power. The efficiency evaluated at maximum cooling power, and the global maximum efficiency may provide improved bench-mark bounds on thermal efficiencies of certain real irreversible refrigeration cycles.
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Swart, JC. "Solar refrigeration using the Peltier Effect." Thesis, Cape Technikon, 1996. http://hdl.handle.net/20.500.11838/1153.
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Thesis (Master Diploma (Electrical Engineering))--Cape Technikon, Cape Town,1996In order to design a coolerbox, utilising Thermo-electric technology as a heat pump, it was necessary to determine if this type of technology would be suitable for a coolerbox heat pump application. A detailed TEC (Thermo Electric Cooler) sizing estimation was done, using formulas supplied by the manufacturer, and using thermo-electric themy formulas to calculate the absolute theoretical performance parameters for a suitable TEe The correct heat pumping capability is important since.it is possible to obtain TEes with different input currents, voltages and heat pumping capabilities. Using the TEC as a heat pump, it was decided to use water cooling due to the extremely high cost of a suitable air cooled heatsink. It should be noted that to cool the hot side of theTEe a vel}' efficient heat exchanger should be used. A simulator was constructed to simulate, under variable operating temperatures and input powers, the cooling capacity of the TEC heat exchanger. The cooling characteristics were then used to determine if the theol}' and manufacturers claims correspond with the cooling characteristics of the coolerbox. It might be possible that the performance of the TEC would be drastically influenced, since installation con~itions may not be ideal when installed; and, that the manufacturers performance claims are done when the TEC is operated under ideal conditions. This would ensure optimum results because, should an under sized TEC be used, the result would be poor cooling characteristics; or, if the TEC is over sized, the coolerbox would consume too much power, resulting in an inefficient system.
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Schneider, Thomas. "An experimental investigation of the finite time efficiency of a Peltier refrigeration device." PDXScholar, 1991. https://pdxscholar.library.pdx.edu/open_access_etds/4261.
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Since the need of energy conservation has become more and more urgent in the past decades, there has been an increased interest in the study and development of more efficient energy conversion systems. One of the fields that have arisen from that endeavor is a branch of physics called Finite Time Thermodynamics (FIT). It may be said that FIT was initiated through the famous paper by Curzon and Ahlborn (1975) that established new bounds on the efficiency of a finite time Carnot heat engine. Before, the traditional treatments gave a fundamental upper limit on the efficiency of any heat engine. However, this figure, the well-known Carnot efficiency, is far too optimistic in comparison to real heat engines. The reason lies in the fact that the traditional Carnot engine is operating infinitely slowly, thus having zero power output. Curzon and Ahlborn were able to improve upon this treatment and to set an upper limit on engines producing finite power.
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Chen, Chung-Kang. "Applications of substructuring methods to the dynamic finite element analysis of a container refrigeration unit frame structure /." Online version of thesis, 1992. http://hdl.handle.net/1850/11688.
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Hill, John Michael. "Simulation of a variable speed air conditioner as a multiple loop thermal system." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/16754.
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Joyce, Charles Thane. "Optimized design of a commercial building chiller/cooking tower system." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/24115.
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Nascimento, Ubiraci Silva. "Carvão de babaçu como fonte termica para sistema de refrigeração por absorção no estado do Maranhão." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265326.
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Orientador: Jorge Isaias Llagostera BeltranDissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-04T02:56:29Z (GMT). No. of bitstreams: 1 Nascimento_UbiraciSilva_M.pdf: 4551351 bytes, checksum: d36f11b4eb3e73786c0d3e1a3785be33 (MD5) Previous issue date: 2004
Resumo: Neste trabalho procurou desenvolver-se uma análise teórica da utilização integral do babaçu como fonte energética, procurando da ênfase às potencialidades agregadas ao carvão. Foi realizado um estudo de caso em municípios maranhenses, visando diagnosticar aspectos que relacionam o homem do campo a essa importante fonte de biomassa. Um forno foi projetado para a produção do carvão do babaçu com melhores índices de qualidade e quantidade. O sistema de refrigeração consta de um acoplamento do forno acionado com carvão de babaçu uma geladeira de absorção tipo Platen-Munters, através de um termosifão bifásico fechado. Os resultados obtidos decorreram de uma análise comparativa a um experimento já realizado com um sistema similar, movido a um fogão à lenha, onde percebe-se claramente uma melhoria significativa da eficiência do sistema proposto
Abstract: In this work a theoretical analysis of the integral use of Babaçu looked for to develop itself as energy source, looking for to give emphasis to the aggregate potentialities to the coal. A study of case in maranhenses cities was carried through, aiming at to diagnosis aspects that relate the man of the field to this important source of biomass. The refrigeration system consists of a coupling of the oven a set in motion with coal of Babassu na absorption refrigerator Platen-Munters type, through a closed two-phase thermosiphon. The gotten results had a similar system, moved to a stove to the firewood, where a significant improvement of the efficiency of the considered system is perceived clearly
Mestrado
Refrigeração de Condicionamento Ambiental
Mestre Profissional em Engenharia Mecanica
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Belaid, Ashur Belaid. "A six-chamber medium-to-high temperature refrigeration system for laboratory purposes." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2522.
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Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2017.Food and water fuel and sustain life on earth. Since ancient times, their sourcing and preservation have been very important issues to humanity. In modern times, experimentation is a major step in analysing how cold storage problems in the medical and food science technology fields can be addressed. For investigating spoilage of new products and/or growth of pathogens in such cases, it is necessary to do experiments at different low temperatures for prolonged periods and check the effects. While this can be undertaken in a conventional two chambers fridge, it takes a long time to investigate a whole range of feasible storage temperatures. This dissertation describes work intended to treble the samples in such investigations and, therefore, significantly reduce the times. Six well- insulated chambers were constructed from plastic and wood and set at different temperatures. An ordinary deep freezer was used as the main heat sink for the chambers. Experiments were done with different methods to get the best result for the cold air flow into the chambers over period of eight months. The chambers temperatures were set between 0 and 15°C. It was finally established that a properly-designed six-chamber system could successfully be added to an ordinary freezer to provide different medium-to-high refrigeration temperatures without the use of a multi-pressure refrigeration cycle.
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White, S. D. "Design and modelling of novel absorption refrigeration cycles /." Title page, contents and summary only, 1993. http://web4.library.adelaide.edu.au/theses/09PH/09phw5878.pdf.
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Conrad, Theodore Judson. "Miniaturized pulse tube refrigerators." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41108.
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Pulse tube refrigerators (PTR) are robust, rugged cryocoolers that do not have a moving component at their cold ends. They are often employed for cryogenic cooling of high performance electronics in space applications where reliability is paramount. Miniaturizing these refrigerators has been a subject of intense research interest because of the benefits of minimal size and weight for airborne operation and because miniature coolers would be an enabling technology for other applications. Despite much effort, the extent of possible PTR miniaturization is still uncertain.
To partially remedy this, an investigation of the miniaturization of pulse tube refrigerators has been undertaken using several numerical modeling techniques. In support of these models, experiments were performed to determine directional hydrodynamic parameters characteristic of stacked screens of #635 stainless steel and #325 phosphor bronze wire mesh, two fine-mesh porous materials suitable for use in the regenerator and heat exchanger components of miniature PTRs. Complete system level and pulse tube component level CFD models incorporating these parameters were then employed to quantitatively estimate the effects of several phenomena expected to impact the performance of miniature PTRs. These included the presence of preferential flow paths in an annular region near the regenerator wall and increased viscous and thermal boundary layer thicknesses relative to the pulse tube diameter. The effects of tapering or chamfering the junctions between components of dissimilar diameters were also investigated.
The results of these models were subsequently applied to produce successively smaller micro-scale PTR models having total volumes as small as 0.141 cc for which sufficient net cooling was predicted to make operation at cryogenic temperatures feasible.
The results of this investigation provide design criteria for miniaturized PTRs and establish the feasibility of their operation at frequencies up to 1000 Hz with dimensions roughly an order of magnitude smaller than those that have recently been demonstrated, provided that challenges related to their regenerator fillers and compressors can be addressed.
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Jurns, John M. "Flow of sub-cooled cryogens through a Joule-Thomson device : investigation of metastability conditions." Cleveland, Ohio : Cleveland State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=csu1198954696.
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Thesis (M.S.)--Cleveland State University, 2007.Abstract. Title from PDF t.p. (viewed on May 8, 2008). Includes bibliographical references (p. 80-82). Available online via the OhioLINK ETD Center. Also available in print.
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Duke, Connor R. "Optimization of control source and error sensor locations in free field active noise control /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2087.pdf.
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Kelly, Allan D. "Dynamic finite element modeling and analysis of a hermetic reciprocating compressor." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-01242009-063231/.
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Craun, Matthew Ashby. "Identification of sound transmission paths within a hermetic reciprocating refrigeration compressor via multiple-input/single-output modeling." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-09192009-040610/.
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Golden, James Hollis. "Ammonia - water desorption in flooded columns." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44884.
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Refrigeration systems employing the NH3-H2O absorption cycle provide cooling using a thermal energy input. This cycle relies on the zeotropic nature of the refrigerant - absorbent pair: because of the difference in boiling temperatures between NH3 and H2O, they can be separated through selective boiling in the desorber. Desorbers with counter-current flow of the solution and generated vapor enable efficient heat and mass transfer between the two phases, reducing the absorbent content in the generated vapor.
Flow visualization experiments at temperatures, concentrations and pressures representative of operating conditions are necessary to understand the heat and mass transfer processes and flow regime characteristics within the component. In this study, a Flooded Column desorber, which accomplishes desorption of the refrigerant vapor through a combination of falling-film and pool boiling, was fabricated and tested. Refrigerant-rich solution enters the top of the component and fills a column, which is heated by an adjacent heated microchannel array. The vapor generated within the component is removed from the top of the component, while the dilute solution drains from the bottom.
Flow visualization experiments showed that the Flooded Column desorber operated most stably in a partially flooded condition, with a pool-boiling region below a falling-film region. It was found that the liquid column level was dependent on operating conditions, and that the pool-boiling region exhibits aggressive mixing between the vapor and solution phases.
Heat transfer coefficients were calculated from the data for the pool-boiling region, and were compared with the predictions of several mixture pool-boiling correlations from the literature. The correlations from the literature were in general unable to predict the data from this study adequately. It was found that the Flooded Column desorber yielded higher heat transfer coefficients within the pool-boiling region than those predicted by these correlations. Therefore, modifications to existing mixture boiling correlations are suggested based on the findings of this study. The resulting modified correlation predicts 33 of the 35 data points from this study within ±40%, with an average absolute error of 19%.
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Sharp, Joshua Glenn. "Experimental determination of the feasibility of waste heat recovery in data centers using ejector based refrigeration." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41060.
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The purpose of this thesis is to experimentally determine the feasibility of an ejector based, waste heat recovery driven refrigeration system applied to the data center environment in order to reduce operational cooling costs. A comprehensive literature review is detailed to determine the current state of the ejector refrigeration research and assess the initial direction of this thesis. A simplified model was created to perform preliminary performance estimations and system sizing before constructing an experimental system apparatus to evaluate the model predictions. The pressures and temperatures used in the model and instituted in the experimental system are based on the maximum temperatures typically observed in computing servers (50-75°C). Precision controlled heaters are used to simulate the computer server heat, and R245fa is used as the working fluid. Performance results ranged from 0.06 to 0.13.
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Alkilani, Fouad M. "A solar assisted high temperature refrigeration system for postharvest pre-storage fruit cooling." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2557.
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Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2017.Agriculture has emerged as a major economic activity in the African continent. Therefore, fruits and vegetables are considered as essential source of vitamins, minerals and proteins. However, fruits and vegetables are perishing rapidly. Thus, the adequate handling starts from the field, by applying appropriate method of storage and preservation in order to reduce post-harvest losses and extend its shelf life. Preservation by removing heat from the products is the most common method of preservation. In rural areas, the access to the grid is expensive or in some cases impossible. Therefore, researchers have been paying more attention to find alternative sources of power to run the cooling units. This study provides proof of a concept for the use of solar energy to cool down harvested fruits and vegetables at the farm level to an adequate farm storage temperature. The target storage temperature range is between 5 and 15 oC. A model refrigerator was designed and constructed in the mechanical engineering workshop of Cape Peninsula University of Technology. It was installed and tested in outdoor conditions to get the effect of different weather conditions. The model consists of a typical vapour compression system powered by a 12 V solar PV system. A DC compressor was used, and therefore, there is no inverter. The model was first tested without a product and then with 20 kg batches of different fruits for a period of two weeks in April 2016. Wind speed, ambient temperature and solar radiation intensity data were monitored and collected from a Campbell Scientific weather station mounted on the roof adjacent to the model. By monitoring the temperatures and compressor current hourly, the refrigeration effect, power consumption and coefficient of performance were determined. The overall COP based on input solar energy was 2.8. It was thus proved that a suitably sized PV system could be designed and implemented at farm level to cool harvested fruits from ambient to storage temperature without the use of an inverter. This could go some way to helping retard deterioration of fruits and vegetables before delivery to a marketplace or to storage.
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You, Ying 1962. "A solar adsorption refrigeration system operating at near atmospheric pressure." Monash University, Gippsland School of Engineering, 2001. http://arrow.monash.edu.au/hdl/1959.1/8740.
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Yeung, King-ho, and 楊景豪. "An optimization model for a solar hybrid water heating and adsorption ice-making system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B29632432.
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Zingano, Bernard Wilson. "Effects of solar radiation on buildings and thermal comfort." Thesis, University of Hertfordshire, 2003. http://hdl.handle.net/2299/14151.
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This work was undertaken to investigate the perceived problem of Thermal Discomfort in Malawi. One observable effect of thermal discomfort was the amount of foreign exchange that was spent to import air conditioning devices. The purpose of the work was to find out, and quantify the problem of thermal discomfort and outline its effects to the people and country. In order to investigate the problem of thermal discomfort in depth in a place where the necessary data hardly existed a lot of work had to be done. The work has been outlined in four stages of research, analysis and documentation and these are as follows 1 Literature Review The subject of Thermal Comfort appears to be location specific, but the general principles are universal. In that context it was necessary to read widely on both historical and contemporary current work. The problem of thermal comfort in general was being discussed as early as 1758 and still remains a big area of research and discussion today. A considerable number of literature that specifically relate to the problem of thermal comfort in the tropics has been reviewed. The problem of scales for thermal comfort measurement has been discussed in detail. It is still not possible to quote a scale that is satisfactory. However, the recent approach of Adaptive Thermal Comfort Model seems to be closer to the answer than the others 2 Analysing Existing Relevant Information And Data In Malawi In the course of this work it was found out that quite a large amount of useful data existed in Malawi. However, this data was not standardised. Most of this data had to be cleaned and updated. Some of the old formulae are quoted in their original formats in order not to confuse the referencing. The data that exists in Malawi has been recorded on three types of instruments; namely the Gunn Bellum Spherical Pyranometer, the Camp Bell Stoke Sunshine Recorder and the Eppley Pyranometer. Most of the data was recorded using the Camp Bell Stokes Sunshine Recorder. The data recorded on the Gunn Bellum Spherical Pyranometer had to be related to that from the Camp Bell Stokes Sunshine Recorder. The former gave data that was more accurate as was found out when a comparison was made with data recorded on an Eppley Pyranometer. A paper on this subject was accepted for publication in the Renewable Energy Journal of WREN. Wind speeds, air temperatures, and humidity have been analysed to investigate the severity of thermal discomfort relative to locations in Malawi. This has resulted in the identification of three climatic zones. A tool for testing Thermal Discomfort severity of a location by calculating number Degree Days (D. d) if the altitude (AL) has been developed; as D. d = -575.994 In AL + 4226.6 3 Field Measurements In order to investigate some of the issues that came out of this work, it was felt simpler to conduct field measurements. For example it would have been possible to build typical experimental houses, and extract performance data on Thermal Comfort from these buildings. However, this approach would have been very expensive. On the other hand it was felt that it was possible to find in the field that were representative of typical buildings and could be prepared and tested to extract performance data for use in the work. The latter approach was adopted and has proved to be more realistic than the former. 4 Field Surveys There were certain areas where the only way to find information was not to conduct experiments but to conduct field conduct surveys. This was done once to find the Preferred Bath Water Temperature (PBWT) and deduce the Neutral Temperature Range for Malawi. This yielded very useful results. The first published paper on this work was in this area (copy of this publication is attached). The second area of field survey was to survey traditional buildings in seven selected districts stretching from latitude 9°S to 17°S; covering a terrestrial distance of over 1000 km; over altitudes from 52 to over 1600 metres above mean sea level (m. a. m. s. l). This again yielded very useful environmental data that explained why traditional buildings have certain structural elements as functions of the environment and the need to achieve Thermal Comfort. A number of useful equations have been developed. From that sub routine of this research of PBWT survey an equation was developed that related the bath temperature (h) to the air temperature (tab) as; tb =0.3772 tab + 36.4401. Part of this work was also published separately in 2001. From this equation the Thermal Comfort Temperature Range for Malawi was deduced as 22-27°C. From the survey of the traditional buildings, a number of structural elements were that are functions of Thermal Comfort were identified as derivatives of the desire to have Thermal Comfort in the buildings. A regression equation that can give values of irradiation of the locality in MJm 1 Day' was developed. Lastly the results have been extracted as recommendations directed at policy makers, and both Architects and Engineers to use this data and the results in their design work. It is also further recommended that the national buildings regulations could be updated and revised to incorporate some of the findings. It is strongly believed that some of the findings will be incorporated to update the two main Laws that regulate Public Health in Malawi. These are the Public Health Act; Cap. 34.01, and the Health and Safety at Work Act, 1977; of the Malawi Laws. All data that has been cleaned up or measured specifically for this work has been organised and tabulated into ready-to-use tables and are included.
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Al-Ansary, Hany A. "Investigation and improvement of ejector-driven heating and refrigeration systems." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/36540.
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Soares, Darrow P. "Curriculum in mathematics for air conditioning and refrigeration." CSUSB ScholarWorks, 1996. https://scholarworks.lib.csusb.edu/etd-project/1239.
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Fourie, Marna. "A subcritical and transcritical carbon dioxide refrigeration system utilizing multiple expansion devices." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86380.
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Thesis (MScEng)--Stellenbosch University, 2014.ENGLISH ABSTRACT: Carbon dioxide is a natural gas that has been used as a refrigerant as far back as the 1850s. It was then primarily used because it was easily obtainable and non-toxic. Due to the high operating pressure and relatively low critical temperature (and high critical pressure) of CO2, it was gradually phased out and replaced with hydrochlorofluorocarbons and chlorofluorocarbons. With the discovery of the greenhouse effect, greenhouse gasses and ozone depleting gasses, the Montreal Protocol and the Kyoto Protocol were placed into effect. These two protocols call for the reduction in use of certain greenhouse gasses and the complete exclusion of others. The focus turned to natural gasses that are more environmentally friendly and easier to come by. Carbon dioxide is one such gas. However, CO2 has a low critical temperature and high pressure, 33.98 °C and 73.77 bar respectively. CO2 refrigeration systems are more effective, have a greater coefficient of performance and have a greater operating temperature difference (over the gas-cooler) when used under transcritical conditions. It is preferred to have transcritical CO2 refriger-ation systems. The drawback of such a system is the extreme operating conditions. A special system must be designed, built and commissioned at the University of Stellenbosch. The system will demand the use or manufacture of unique, special-ised components. Most of the components utilised are extremely expensive and/or difficult to come by, or designed and manufactured specifically for this system. The CO2 system at the University of Stellenbosch is exceptional and stands out from conventional systems in that: - it can operate under both the subcritical and transcritical conditions; - it has multiple expansion units, which can be alternated, giving a total of four different operating configurations; - the system can run with fully automated controllers or as a static system; - the internal heat exchanger can be included or excluded from the system; - all the heat exchangers can run in counter flow or parallel flow; and - The system has multiple testing points, for both temperature and pressure, to give the operator accurate measurements to be used in comparison with design software, etc. Three simulation programs are given that describe the physical system. The first simulation program is a steady-state simulator used to aid in the design of the heat exchangers and the capillary tube. The second simulator is a steady-state program that determines the mass flow rate in the capillary tube. The third simulation is a transient program, programmed to determine the steady-state conditions of a sys-tem, given set initial conditions and a transient start-up.
AFRIKAANSE OPSOMMING: Koolstofdioksied is 'n natuurlike gas wat gebruik word as 'n verkoelingsmiddel so ver terug as die 1850's. Dit is toe hoofsaaklik gebruik omdat dit maklik verkrygbaar en nie giftig is nie. As gevolg van die hoë werksdruk en relatief lae kritiese temperatuur (en hoë kritiese druk) van CO2, is dit geleidelik uitgefaseer en vervang met hidrochloorfluoorkoolstof en chloorfluoorkoolstowwe. Met die ontdekking van die kweekhuiseffek, kweekhuisgasse en osoon-afbrekende gasse, is die Montreal-protokol en die Kyoto-protokol in werking gestel. Hierdie twee protokolle vereis die afname in die gebruik van sekere kweekhuisgasse en die algehele uitsluiting van ander. Die fokus het verskuif na natuurlike gasse wat omgewingsvriendeliker en makliker is om te bekom. Koolstofdioksied is so 'n gas. Maar CO2 het 'n lae kritiese temperatuur en hoë kritiese druk, 33.98 °C en 73.77 bar onderskeidelik. CO2 verkoelingstelsels is meer effektief, het 'n groter koëffisiënt van werksverrigting en het 'n groter bedryfstemperatuur-verskil (oor die gas-verkoeler) wanneer dit gebruik word onder transkritiese toestande. Dit is dus verkieslik om transkritiese CO2 verkoelingstelsels te hê. Die nadeel van so 'n stelsel is die relatief uiterste bedryfstoestande. 'n Spesiale stelsel moet ontwerp word, dikwels met die gebruik of vervaardiging van unieke, hoogs gespesialiseerde komponente. So 'n stelsel is ontwerp vir die Universiteit van Stellenbosch. Die meeste van die komponente wat gebruik is, is baie duur en/of moeilik om te bekom, of is spesifiek ontwerp en vervaardig vir hierdie stelsel. Die CO2-stelsel by die Universiteit van Stellenbosch is uitsonderlik en staan uit bo konvensionele stelsels deurdat: - dit kan funksioneer onder beide subkritiese en transkritiese toestande; - dit verskeie gasuitsettings-eenhede het, wat afgewissel kan word, wat 'n totaal van vier verskillende bedryfskonfigurasies gee; - die stelsel bedryf kan word met volle outomatiese beheerders of as 'n statiese stelsel; - die interne hitte-uitruiler óf in-, óf uitgesluit kan word van die stelsel; - al die hitte-uitruilers bedryf kan word in kontra-vloei of parallelle vloei; en - die stelsel verskeie toetspunte het, vir beide temperatuur en druk, wat die operateur akkurate metings gee om te vergelyk met die ontwerp sagteware, ens., wat gebruik word. Drie gegewe simulasieprogramme beskryf die fisiese stelsel. In een simulasie word 'n bestendige toestand-simulator gebruik om te help met die ontwerp van die hitteruilers en die kapillêre buis. Die tweede simulasie program is 'n bestendige toestands-program wat die algehele vloeitempo in die kapillêre buis bepaal. Die laaste simulasie is 'n vlugtige program, geprogrammeer om die tydelike toestande van 'n stelsel te bepaal, gegewe vasgestelde aanvanklike toestande en 'n kortstondige aanskakeling.
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Mulcahey, Thomas Ian. "Convective instability of oscillatory flow in pulse tube cryocoolers due to asymmetric gravitational body force." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51808.
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Pulse tube cryocoolers (PTCs) are among the most attractive choices of refrigerators for applications requiring up to 1 kW of cooling in the temperature range of 4-123 K as a result of the high relative efficiency of the Stirling cycle, the reliability of linear compressors, and the lack of cryogenic moving parts resulting in long life and low vibration signature. Recently, PTCs have been successfully used in applications in the 150 K range, extending the useful range of the device beyond the traditional cryogenic regime. A carefully designed cylindrical cavity referred to as the pulse tube replaces the mechanical expander piston found in a Stirling machine. A network consisting of the pulse tube, inertance tube, and surge volume invoke out-of-phase pressure and mass flow oscillations while eliminating all moving parts in the cold region of the device, significantly improving reliability over Stirling cryocoolers. Terrestrial applications of PTCs expose a fundamental flaw. Many PTCs only function properly in a narrow range of orientations, with the cold end of the pulse tube pointed downward with respect to gravity. Unfavorable orientation of the cold head often leads to a catastrophic loss of cooling, rendering the entire cryocooler system inoperable. Previous research indicates that cooling loss is most likely attributed to secondary flow patterns in the pulse tube caused by free convection. Convective instability is initiated as a result of non-uniform density gradients within the pulse tube. The ensuing secondary flow mixes the cryogen and causes enhanced thermal transport between the warm and cold heat exchangers of the cryocooler.
This study investigates the nonlinear stabilizing effect of fluid oscillation on Rayleigh-Bénard instability in a cryogenic gas subject to misalignment between gravitational body force and the primary flow direction. The results are directly applicable to the flow conditions frequently experienced in PTCs. Research has shown that the convective component can be minimized by parametrically driven fluid oscillation as a result of sinusoidal pressure excitation; however, a reliable method of predicting the influence of operating parameters has not been reported. In this dissertation, the entire PTC domain is first fully simulated in three dimensions at various angles of inclination using a hybrid method of finite volume and finite element techniques in order to incorporate conjugate heat transfer between fluid domains and their solid containment structures. The results of this method identify the pulse tube as the sole contributor to convective instability, and also illustrate the importance of pulse tube design by incorporating a comparison between two pulse tubes with constant volume but varying aspect ratio. A reduced domain that isolates the pulse tube and its adjacent components is then developed and simulated to improve computational efficiency, facilitating the model’s use for parametric study of the driving variables. A parametric computational study is then carried out and analyzed for pulse tubes with cold end temperatures ranging from 4 K to 80 K, frequencies between 25-60 Hz, mass flow - pressure phase relationships of -30◦ and +30◦, and Stokes thickness-based Reynolds numbers in the range of 43-350, where the turbulent transition occurs at 500.
In order to validate the computational models reported and therefore justify their suitability to perform parametric exploration, the CFD codes are applied to a commercially developed single stage PTR design. The results of the CFD model are compared to laboratory-measured values of refrigeration power at temperatures ranging from 60 K to 120 K at inclination angles of 0◦ and 91◦. The modeled results are shown to agree with experimental values with less than 8.5% error for simulation times of approximately six days using high performance computing (HPC) resources through Georgia Tech’s Partnership for Advanced Computing (PACE) cluster resource, and 10 days on a common quad-core desktop computer. The results of the computational parametric study as well as the commercial cryocooler data sets are compiled in a common analysis of the body of data as a whole. The results are compared to the current leading pulse tube convective stability model to improve the reliability of the predictions and bracket the range of losses expected as a function of pulse tube convection number. Results can be used to bracket the normalized cooling loss as a function of the pulse tube convection number NPTC. Experimental data and simulated results indicate that a value of NPTC greater than 10 will yield a loss no greater than 10% of the net pulse tube energy flow at any angle. A value of NPTC greater than 40 is shown to yield a loss no greater than 1% of the net pulse tube energy flow at all angles investigated.
The computational and experimental study completed in this dissertation addresses static angles of inclination. Recent interest in the application of PTCs to mobile terrestrial platforms such as ships, aircraft, and military vehicles introduces a separate regime wherein the angle of inclination is dynamically varying. To address this research need, the development of a single axis rotating cryogenic vacuum facility is documented. A separate effects apparatus with interchangeable pulse tube components has also been built in a modular fashion to accommodate future research needs.
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Forson, Francis Kofi. "Modelling and experimental investigation of a mixed-mode natural convection solar crop dryer (MNCSD)." Thesis, De Montfort University, 1999. http://hdl.handle.net/2086/4201.
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Augustyn, Ockert Philippus Hermanus. "Experimental and numerical analysis of axial flow fans." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85720.
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Thesis (MScEng)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The majority of power stations in South Africa are located in coal rich, but arid regions where wet-cooled condenser systems are not feasible from an environmental and economic perspective. Consequently the focus on power generation cooling has shifted towards dry-cooling systems using air-cooled steam condensers (ACSC). The steam passing through the ACSC units is cooled by an air-draught, mechanically induced by large diameter axial flow fans. Consequently the effectiveness of the cooling is impacted by the performance of these fans, which ultimately affects the overall efficiency of the power plant. However, due to the large diameters (> 10 m) of these fans, their performance is predicted based on small scale test results using the fan scaling laws. The objective of this project was to develop a methodology which accurately predicts the fan performance of more than one fan configuration using computational fluid dynamics (CFD) software and validating the results with experimental tests. Four fans were considered in this study of which three were scaled fan models of large air-cooled axial fans. The performance of the scaled fan models (L1-, L2- and N-fan) were measured in a type A, BS 848 standard fan test facility. The geometries of the fans were scanned three-dimensionally to obtain the models for simulation purposes. The other fan considered was an 8- bladed axial fan designed by Bruneau (1994) and referred to as the B-fan. Simulations were carried out for the L2-, N- and B-fan for different computational domains while implementing the multiple reference frames (MRF) and steady RANS approach. Three variations of the k-ε turbulence model were also investigated. Noticeable differences were found between the experimental and numerical results of the B-fan. Good correlations between the numerical and experimental fan static pressure, fan power and fan static efficiency were found for the two scaled model fans over a large operating range. The performance of the full scale fans, however, did not correlate well with the performance of the scaled models. It is concluded that accurate simulations of axial fans are possible although these domains require a large number of mesh elements. It is recommended that further research is carried out to investigate the relationship between full scale and small scale fan models.
AFRIKAANSE OPSOMMING: Die meerderheid steenkool kragstasies in Suid-Afrika is geleë in droë, maar steenkool ryke streke waar natverkoelde kondensor stelsels uit ʼn omgewings en ekonomiese perspektief nie geskik is nie. Die fokus in kragopwekking verkoeling het dus verskuif na droë-verkoelings stelsels en spesifiek die gebruik van lugverkoelde stoomkondensors (LVSKs). Die stoom in LVSK eenhede word verkoel deur atmosferiese lug wat meganies geïnduseer word deur groot aksiaalvloeiwaaiers. Die effektiwiteit van die verkoelingsproses word gevolglik beïnvloed deur die werksverrigting van hierdie waaiers wat uiteindelik die algehele effektiwiteit van die kragstasie beïnvloed. As gevolg van hierdie waaiers se grootte word hulle werksverrigting egter bepaal op grond van kleinskaal toetsresultate en deur gebruik te maak van die waaierskaleringswette. Die hoofdoelwit van hierdie projek was om ‘n metodiek te ontwikkel wat die werksverrigting van ʼn aksiaalwaaier akkuraat kan voorspel vir ʼn verskeidenheid opstellings, deur gebruik te maak van berekenings vloei meganika (BVM) sagteware en die resultate eksperimenteel te verifieer. Die projek het vier waaiers ondersoek waarvan drie van hierdie waaiers geskaleerde modelle van groot lugverkoelde aksiaalwaaiers was. Die werksverrigting van die geskaleerde waaiers (L1-, L2- en N-waaier) was met ‘n tipe A, BS 848 standaard waaier toetsfasiliteit gemeet. Die geometrie van dié waaiers was ook drie-dimensioneel opgemeet vir simulasie doeleindes. Die B-waaier, ‘n 8 lem aksiaalwaaier, wat ontwerp is deur Bruneau (1994) was slegs numeries ondersoek. Die L2-, N- en Bwaaier was gesimuleer in verskillende berekeningsdomeine deur gebruik te maak van die multi verwysingsraamwerk en gestadigde vloeiberekenings benaderings. Drie k-ε turbulensie modelle was ook ondersoek. Merkbare verskille tussen die eksperimentele en numeriese resultate van die Bwaaier was waargeneem. Goeie korrelasie tussen die eksperimentele en numeriese resultate van die geskaleerde waaiers vir ‘n wye bedryfsbestek was gevind. ‘n Vergelyking tussen die volskaal en kleinskaal waaiers se werksverrigting het egter beduidende afwykings aangetoon. Deur gebruik te maak van ‘n groot aantal selle in die berekeningsdomein was dit moontlik om ʼn verskeidenheid aksiaalvloeiwaaiers akkuraat te simuleer. Verdere navorsing wat die verhouding tussen volskaal en kleinskaal waaiers ondersoek woord aanbeveel.
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Kroger, Detlev G. "Air-cooled heat exchangers and cooling towers : thermal-flow performance evaluation and design." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/49822.
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Thesis (PhD)--Stellenbosch University, 2004.ENGLISH ABSTRACT: During the last 30 years I have been involved in the theory and practice of thermal engineering and in particular, in the areas of air-cooled heat exchangers and cooling towers for the power, refrigeration, process and petrochemical industries in South Africa and internationally. During this period, I have authored and co-authored more than 120 papers that were published in technical journals or presented at conferences nationally or internationally. Most of these papers are included in a manuscript entitled "Air-cooled Heat Exchangers and Cooling Towers", in which Ipresent a systematic approach to the thermal performance evaluation and design of industrial air-cooled heat exchangers and cooling towers. This original publication also includes the relevant practice applicable to the design of cooling systems, based on my experience as a consultant to industry. Design offices throughout the world presently follow our design methods, or at least employ many of our research results. Our work has furthermore contributed to the development of improved cooling system designs (e.g. new dephlegmator header designs), components (e.g. single-row flattened finned tubes) and product improvement and quality control (e.g. performance testing and measurement of thermal contact resistance between fin and tube during production). Many of our research findings have found application in the modification of existing cooling systems. The manuscript has also been used as reference work during the presentation of short courses to practising engineers and consultants in industry and to engineering graduates at the University of Stellenbosch. A two-volume edition of this manuscript was published by PennWell Corp., Tulsa, Oklahoma, USA in 2004.
AFRIKAANSE OPSOMMING: Gedurende die laaste 30 jaar was ek betrokke by die teorie en praktyk van lugverkoelde warmteoordraers en koeltorings vir die kragopwekkings-, verkoelings-, proses- en petro-chemiesenywerhede in Suid-Afrika sowel as in die buiteland. Gedurende hierdie periode was ek outeur en mede-outeur van meer as 120 publikasies wat in tegniese tydskrifte, of by plaaslike of oorsese konferensies aangebied is. Die meeste van hierdie publikasies vorm deel van 'n manuskrip getiteld "Air-cooled Heat Exchangers and Cooling Towers" waarin ek 'n sistematiese benadering tot die bepaling van die termiese vermoë en ontwerp van industriële lugverkoelde warmteoordraers en koeltorings aanbied. Hierdie oorspronklike publikasie bevat ook die relevante praktyk wat van toepassing is op verkoelingsaanlegte. Ontwerpkantore wêreldwyd volg tans hierdie ontwerpsmetodes, of gebruik ten minste baie van ons navorsingsresultate. Ons werk het verder bygedra tot die ontwikkeling van verbeterde verkoelingsaanlegte (bv. nuwe deflegmatore), komponente (bv. enkelbuisry platvinbuise ) en verbeterde produkte en kwaliteitskontrole (bv. toetsing van verkoelingsvermoë oftermiese kontakweerstand tussen vin en buis gedurende produksie). Baie van ons bevindinge het toepassing gevind in die modifikasie van verkoelingsaanlegte. Die manuskrip is ook as verwysing gebruik gedurende die aanbieding van kort kursusse aan ingenieurs in die praktyk en aan nagraadse studente aan die Universiteit van Stellenbosch. 'n Twee-volume uitgawe van die manuskrip is deur PennWell Corp., Tulsa, Oklahome, VSA in 2004 gepubliseer.
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Hugh, Mark A. "The effects of regenerator porosity on the performance of a high capacity stirling cycle cryocooler." Ohio : Ohio University, 1993. http://www.ohiolink.edu/etd/view.cgi?ohiou1175707790.
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Andrade, Diogo Elias da Vinha. "Modelo para predição de resultados de ensaios de sistemas de refrigeração em tempo real." Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/207.
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Atualmente, a análise de desempenho de sistemas de refrigeração domésticos é realizada através de ensaios experimentais normalizados. Durante esses experimentos, diversas variáveis como pressões de trabalho, temperaturas em diversos pontos do sistema, corrente elétrica e potência consumida, são monitoradas. Porém, em muitos casos são necessárias mais de 24 horas para execução de um teste experimental (e.g., teste abaixamento de temperatura). Tendo em vista o tempo despendido nestes testes, propõe-se no presente trabalho um modelo matemático semi-empírico capaz de predizer o comportamento das variáveis do sistema testado e, com isso, antecipar o final do ensaio. O modelo, desenvolvido através das leis de conservação da massa e da energia, apresenta parâmetros que são ajustados a partir de informações experimentais obtidas durante a execução do próprio teste. Após a inicialização do ensaio, a cada período de tempo prédeterminado, os dados medidos são utilizados para determinar os parâmetros empíricos do modelo. Obtidas as constantes, simula-se o comportamento das principais variáveis do sistema de refrigeração até a condição de regime permanente. Com isso, o teste experimental pode ser finalizado com antecedência. O modelo desenvolvido é capaz de prever com boa precisão, a partir de duas horas de teste, a variação da vazão mássica e da pressão de sucção (com diferenças da ordem de 10% em regime permanente quando comparadas às variáveis experimentais), da pressão de condensação (com diferença da ordem de 5%) e da temperatura da parede do condensador (diferença da ordem de 2°C).The performance of household refrigeration systems are usually evaluated through experimental tests carried at in temperature and humidity controlled chambers. During the tests, the discharge and suction pressures, the temperature in several system positions, and the compressor power are measured. These tests are expensive and time-demanding, e.g., a single pull-down test can take more than 24 hours to be performed. Although the mathematical models have been proposed for decades as an alternative to the experiments, they are not sufficiently reliable to substitute completely the tests. Therefore, the current work proposes a semiempirical mathematical model to predict the system performance with the purpose of reducing the test time instead of replacing it. The model is based on the mass and energy conservation equations in which the constant parameters, such as conductance and capacitances, are calibrated from previous measured values of temperature and pressure. As soon as the parameters are obtained, a simulation is performed to forecast future values of temperature, pressure and compressor power and therefore, to anticipate the end of the test. Calibrations and simulations can be continuously performed as the test evolves. Preliminary results show that steadystate values of discharge and suction pressures can be predicted within error bands of 5 and 10%, respectively, after only two hours of a pull-down test being performed.
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Landrum, Evan. "Anisotropic parameters of mesh fillers relevant to miniature cryocoolers." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28159.
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Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Ghiaasiaan, S. Mostafa; Committee Member: Desai, Prateen; Committee Member: Jeter, Sheldon; Committee Member: Kirkconnell, Carl.
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Clearman, William M. "Measurement and correlation of directional permeability and Forchheimer's inertial coefficient of micro porous structures used in pulse tube cryocoolers." Thesis, Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-07092007-111541/.
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Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2008.Kirkconnell, Carl S., Committee Member ; Ghiaasiaan, S. Mostafa, Committee Chair ; Desai, Prateen V., Committee Member ; Jeter, Sheldon M., Committee Member.
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Tipton, Russell C. "Simulation of a storage freezer operating with a binary nonazeotropic refrigerant blend part I. equation of state cycle selection compressor model and air-cooled condenser model." Ohio : Ohio University, 1989. http://www.ohiolink.edu/etd/view.cgi?ohiou1182524272.
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Rezk, Ahmed Rezk Masoud. "Theoretical and experimental investigation of silica gel/water adsorption refrigeration systems." Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/3623/.
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This PhD project was set out to improve the performance of silica gel / water adsorption cooling systems using a number of investigation tools. A novel global lumped analytical simulation model has been constructed for a commercialised two-bed silica gel / water 450kW adsorption chiller. It was integrated with a genetic algorithm (GA) optimisation toolbox to determine the optimum operating conditions to obtain the optimum chiller performance. The model was used to investigate the effect of physical and operating on the chiller performance. The model was also used to investigate the effect of various adsorbent bed enhancement techniques that are presented in published literature. An experimental test facility has been designed, constructed and commissioned to study the performance of scaled down adsorbent bed modules. It has been constructed to understand the effect of the operating conditions on adsorbent-bed heat and mass transfer performance. A dynamic vapour sorption (DVS) gravimetric analyser has been used to characterise a new species of adsorbents (MOFs). These adsorbents have strong potential towards water sorption and could replace the currently applied silica gel. MOFs adsorbents have been characterised in terms of adsorption isotherms and kinetics, in addition to its cyclic analysis. It was found that HKUST-1 (copper based MOF) outperforms silica gel with 95.7% increase in the water uptake. Iron based MOF (MIL-100) was found to outperform silica gel for high evaporating temperature application.