Academic literature on the topic 'Refrigeration capacity distribution'
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Journal articles on the topic "Refrigeration capacity distribution"
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Yang, Shutong, Youlei Wang, and Yufei Wang. "Optimization of Cascade Cooling System Based on Lithium Bromide Refrigeration in the Polysilicon Industry." Processes 9, no. 9 (September 18, 2021): 1681. http://dx.doi.org/10.3390/pr9091681.
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Cascade cooling systems containing different cooling methods (e.g., air cooling, water cooling, refrigerating) are used to satisfy the cooling process of hot streams with large temperature spans. An effective cooling system can significantly save energy and costs. In a cascade cooling system, the heat load distribution between different cooling methods has great impacts on the capital cost and operation cost of the system, but the relative optimization method is not well established. In this work, a cascade cooling system containing waste heat recovery, air cooling, water cooling, absorption refrigeration, and compression refrigeration is proposed. The objective is to find the optimal heat load distribution between different cooling methods with the minimum total annual cost. Aspen Plus and MATLAB were combined to solve the established mathematical optimization model, and the genetic algorithm (GA) in MATLAB was adopted to solve the model. A case study in a polysilicon enterprise was used to illustrate the feasibility and economy of the cascade cooling system. Compared to the base case, which only includes air cooling, water cooling, and compression refrigeration, the cascade cooling system can reduce the total annual cost by USD 931,025·y−1 and save 7,800,820 kWh of electricity per year. It also can recover 3139 kW of low-grade waste heat, and generate and replace a cooling capacity of 2404 kW.
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Chen, Xinwen, Zhaohua Li, Yi Zhao, Hanying Jiang, Kun Liang, and Jingxin Chen. "Modelling of Refrigerant Distribution in an Oil-Free Refrigeration System using R134a." Energies 12, no. 24 (December 16, 2019): 4792. http://dx.doi.org/10.3390/en12244792.
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Increasing number of refrigeration units has led to an increase of CO2 emissions and the destruction of the ozone layer. Using low global warming potential (GWP) refrigerants, improving the efficiency of vapour compression refrigeration (VCR) units, and minimising refrigerant leakages can reduce the global warming effect. Investigating the refrigerant distribution under varied operating conditions can provide a deeper understanding of refrigerant charge optimization. This study proposed a model of refrigerant mass distribution in a prototype oil-free VCR system using a linear compressor with variable strokes and R134a. The absence of the oil lubricant allows the adoption of compact heat exchangers, such as micro-channels, so that the total refrigerant charge can be reduced significantly. The predicted total refrigerant charge has a Mean Absolute Percentage Error (MAPE) of 3.7%. The simulation results indicate that refrigerant distributed in the condenser is most sensitive to operating conditions and total refrigerant charges. The refrigerant accumulated in the condenser is 6.8% higher at a total refrigerant charge of 0.33 kg than that of 0.22 kg. For a total refrigerant charge of 0.33 kg, 72.1% of the total refrigerant can accumulate in the condenser. At a fixed pressure ratio, the refrigerant as a two-phase form in the condenser decreases slightly with the increase of compressor strokes, resulting in a larger mass flow rate, thus cooling capacity. The present model can be adapted for optimization of a refrigeration unit and its components.
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Hermes, Christian J. L., Joel Boeng, Diogo L. da Silva, Fernando T. Knabben, and Andrew D. Sommers. "Evaporator Frosting in Refrigerating Appliances: Fundamentals and Applications." Energies 14, no. 18 (September 21, 2021): 5991. http://dx.doi.org/10.3390/en14185991.
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Modern refrigerators are equipped with fan-supplied evaporators often tailor-made to mitigate the impacts of frost accretion, not only in terms of frost blocking, which depletes the cooling capacity and therefore the refrigerator coefficient of performance (COP), but also to allow optimal defrosting, thereby avoiding the undesired consequences of condensate retention and additional thermal loads. Evaporator design for frosting conditions can be done either empirically through trial-and-error approaches or using simulation models suitable to predict the distribution of the frost mass along the finned coil. Albeit the former is mandatory for robustness verification prior to product approval, it has been advocated that the latter speeds up the design process and reduces the costs of the engineering undertaking. Therefore, this article is aimed at summarizing the required foundations for the design of efficient evaporators and defrosting systems with minimized performance impacts due to frosting. The thermodynamics, and the heat and mass transfer principles involved in the frost nucleation, growth, and densification phenomena are presented. The thermophysical properties of frost, such as density and thermal conductivity, are discussed, and their relationship with refrigeration operating conditions are established. A first-principles model is presented to predict the growth of the frost layer on the evaporator surface as a function of geometric and operating conditions. The relation between the microscopic properties of frost and their macroscopic effects on the evaporator thermo-hydraulic performance is established and confirmed with experimental evidence. Furthermore, different defrost strategies are compared, and the concept of optimal defrost is formulated. Finally, the results are used to analyze the efficiency of the defrost operation based on the net cooling capacity of the refrigeration system for different duty cycles and evaporator geometries.
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Wang, Guiqiang, Xiaohang Cheng, Zhiqiangè Kang, and Guohui Feng. "Influence of Airflow Field on Food Freezing and Energy Consumption in Cold Storage." E3S Web of Conferences 53 (2018): 01038. http://dx.doi.org/10.1051/e3sconf/20185301038.
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Currently most food products are cooled and frozen in air-blast cold storage to prolong storage time. The airflow field distribution in storage has a great impact on the process of food freezing and energy cost by that. In this paper, a transient model of food freezing considering airflow field was developed to simulation the temperature profile of air and food products during freezing process. A lumped parameter model was used to predict the temperature and moisture profile of air, which connected all other components together, such as air coolers, food products, envelop enclosure and refrigeration system. A finite difference method was employed to model the heat transfer inside food products during freezing, where the mass transfer was neglected as the food products were wrapped with polystyrene films. Unit load factor method was applied to calculate the sensible heat refrigeration capacity and thus the total capacity of air coolers. The simulation was conducted on a large cold storage filled with large quantities of packaged food products. Results show that there are great differences in airflow field distribution at different locations in cold storage, which lead to spacial differences in freezing time required. Inappropriate set point of freezing time prolongs freezing process unnecessarily and leads to extra energy consumption. Operational mode of air coolers has a great impact on the total energy consumption, as they consume energy themselves and release equivalent heat into storage simultaneously.
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Трушляков, Євген Іванович, Андрій Миколайович Радченко, Микола Іванович Радченко, Сергій Анатолійович Кантор, and Веніамін Сергійович Ткаченко. "ПІДВИЩЕННЯ ЕФЕКТИВНОСТІ КОНДИЦІЮВАННЯ ЗОВНІШНЬОГО ПОВІТРЯ СИСТЕМИ КОМБІНОВАНОГО ТИПУ." Aerospace technic and technology, no. 4 (August 31, 2019): 9–14. http://dx.doi.org/10.32620/aktt.2019.4.02.
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One of the most attractive reserves of enhancing the energetic efficiency of air conditioning systems is to provide the operation of refrigeration compressors in nominal or close to nominal modes by choosing rational design cooling loads (cooling capacities) and their distribution according to a cooling load behaviour within the overall design (installed) cooling load band to match current changeable climatic conditions and provide close to maximum annual cooling capacity generation according to cooling duties. The direction of increasing the efficiency of outdoor air conditioning in combined central-local type systems by rationally distributing the heat load - cooling capacity of the central air conditioner into zones of variable heat load in accordance with current climatic conditions and its relatively stable value, i.e. cooling capacity required for further air cooling at the entrance to the indoor recirculation air conditioning system is justified. By comparing the values of the excessive production of cold and its deficit within every 3 days for a rational design heat load of the air conditioning system (cooling capacity of the installed refrigeration machine), which provides close to maximum annual production of cold, and the corresponding values of the excess and deficit of cooling capacity in accordance with current climatic conditions during July substantiated the feasibility of accumulating the excess of cooling capacity of a central air conditioner at low current loads and its use for covering cooling deficit at elevated heat loads through pre-cooling the outdoor air. It is developed a scheme of a combined central-local air conditioning system, which includes the subsystems for the outdoor air conditioning in a central air conditioner and the local indoor recirculated air conditioning.
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Yang, Zongming, Mykola Radchenko, Andrii Radchenko, Dariusz Mikielewicz, and Roman Radchenko. "Gas Turbine Intake Air Hybrid Cooling Systems and a New Approach to Their Rational Designing." Energies 15, no. 4 (February 17, 2022): 1474. http://dx.doi.org/10.3390/en15041474.
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Gas turbine intake air cooling (TIAC) by exhaust gas heat recovery chillers is a general trend to improve turbine fuel efficiency at increased ambient temperatures. The high efficiency absorption lithium–bromide chillers of a simple cycle are the most widely used, but they are unable to cool inlet air lower than 15 °C. A two-stage hybrid absorption–ejector chillers were developed with absorption chiller as a high temperature stage and ejector chiller as a low temperature stage to subcool air from 15 °C to 10 °C and lower. A novel trend in TIAC by two-stage air cooling in hybrid chillers has been substantiated to provide about 50% higher annual fuel saving in temperate climate as compared with absorption cooling. A new approach to reduce practically twice design cooling capacity of absorption chiller due to its rational distribution with accumulating excessive refrigeration energy at decreased thermal loads to cover the picked demands and advanced design methodology based on it was proposed. The method behind this is issued from comparing a behavior of the characteristic curves of refrigeration energy required for TIAC with its available values according to various design cooling capacities to cover daily fluctuation of thermal loads at reduced by 15 to 20% design cooling capacity and practically maximum annual fuel reduction.
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Wang, Li Juan, Yan Feng Liu, Jia Ping Liu, and Fei Lu. "Study on a New Mathematical Model for Aggregate Air Cooling or Heating." Advanced Materials Research 374-377 (October 2011): 1882–86. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.1882.
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Before the construction of hydraulic structure, aggregate must be cooled or heated by air (we call it aggregate air cooling or heating in this paper) or other technologies to the required temperature. Previous model of aggregate air cooling or heating cannot provide the center temperature of each aggregate. So a more accurate mathematical model is developed to determine the thermal performance of aggregate, and the surface heat transfer coefficient of wet aggregate is revised. This model can predict the center temperature of an aggregate and can accurately calculate the cold down time or temperature distribution of aggregate, so that the refrigeration or heating capacity can be reasonably supplied. It’s significant for foundation engineering of hydraulic structure.
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Hamad, Mahmoud. "Magnetocaloric effect in Sr2FeMoO6/Ag composites." Processing and Application of Ceramics 9, no. 1 (2015): 11–15. http://dx.doi.org/10.2298/pac1501011h.
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The enhanced low-field magnetocaloric effect was investigated for double perovskite Sr2FeMoO6 - silver (SFMO/Ag) composites with 0, 5 and 10 wt.% of Ag. A phenomenological model was used to predict magnetocaloric properties of SFMO/Ag composites, such as magnetic entropy change, heat capacity change and relative cooling power. It was shown that magnetic entropy change (?S M) peaks of SFMO/Ag span over a wide temperature region, which can significantly improve the global efficiency of the magnetic refrigeration. Furthermore, the ?S M distribution of the SFMO/Ag composites is much more uniform than that of gadolinium. Through these results, SFMO/Ag composite has some potential application for magnetic refrigerants in an extended high-temperature range.
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DOIPHODE, PUSHPAK, MANDAR TENDOLKAR, PATRIC ANANDA BALAN, and INDRANEEL SAMANTA. "NUMERICAL ANALYSIS OF CHEST FREEZER'S CONDENSING UNIT." International Journal of Air-Conditioning and Refrigeration 22, no. 04 (December 2014): 1450028. http://dx.doi.org/10.1142/s201013251450028x.
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Chest freezers are high energy consuming refrigeration systems generally used for food storage. In a chest freezer, components such as condenser coil and fan, compressor, expansion device, etc. are placed at one corner of freezer and are covered by grills. All these components together are referred as condensing unit. Position of grills with respect to these components plays an important role in air flow distribution over condenser coil. Present work deals with the study of air flow distribution in condensing unit using Computational Fluid Dynamics (CFD) tool. Performance of the condenser is analyzed using CoilDesigner®. It is found that some air enters from side grill and bypasses the condenser coil without producing any condensing effect, resulting in degradation of performance. Effect of complete blockage of some portion of side grill on air flow distribution over condenser coil and performance of condenser is presented. Quantity of air flowing over condenser coil measured as Cubic Feet per Minute (CFM) and condenser capacity are found to be increased by approximately 10% and 2%, respectively.
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Xie, Jie Fei, Xin Hua Li, and Hong Zhang. "Study on Characteristics of the Linear Air-Conditioner Compressor at Varied Operating Conditions." Advanced Materials Research 201-203 (February 2011): 632–36. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.632.
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This paper mainly introduces a novel linear air conditioner compressor which is driven by the linear oscillatory motor with two divided moving body, of which the Cylinder-piston assembly presents symmetrical distribution along the axial direction. The compressor dynamics equations were built and solved numerically with the fourth order Runge-Kutta method. in the meantime, this paper emphatically analyzes the influence of those factors, such as the intake pressure, the exhaust pressure, the suction gas superheat, the cooling degree, on the compressor performance at varied operating conditions. These works shows that improving the suction gas pressure and reducing the exhuast pressure can help to increase the refrigeration capacity and energy efficiency ratio of the air conditioner compressor. Those analysis results provide theory foundation for design,development, and engineering application of this linear air-conditioner compressor.
Dissertations / Theses on the topic "Refrigeration capacity distribution"
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Trushliakov, Eugeniy, Andrii Radchenko, Mykola Radchenko, Serhiy Kantor, and Oleksii Zielikov. "The Efficiency of Refrigeration Capacity Regulation in the Ambient Air Conditioning Systems." Thesis, 2020. https://doi.org/10.1007/978-3-030-50491-5_33.
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The Efficiency of Refrigeration Capacity Regulation in the Ambient Air Conditioning Systems / E. Trushliakov, A. Radchenko, M. Radchenko, S. Kantor, O. Zielikov // Proceedings of the 3rd Intern. Conf. on Design, Simulation, Manufacturing: The Innovation Exchange «Advances in Design, Simulation and Manufacturing III». – Kharkiv, 2020. – Vol. 244. – P. 343–353.Abstract. The operation of the ambient air conditioning systems (ACS) is characterized by considerable fluctuations of the heat load in response to the current climatic conditions. It needs the analyses of the efficiency of the application of compressors with frequency converters for refrigeration capacity regulation in actual climatic conditions. A new method and approach to analyzing the effectiveness of ACS cooling capacity adjusting by using the compressor with changing the rotational speed of the motor as an example have been developed, according to which the overall range of changeable heat loads is divided into two zones: the zone of ambient air processing with considerable fluctuations of the current heat load, that requires effective refrigeration capacity regulation by the compressor with frequency converters (from 100% rated refrigeration capacity down to about 50%) and not an adjustable zone of reduced refrigeration capacity below 50% rated refrigeration capacity of the compressor. The magnitudes of threshold refrigeration capacity between both zones are chosen according to the rational value of installed (design) refrigeration capacity on the ACS, required for cooling the ambient air to a target temperature that ensures the maximum annual refrigeration capacity production in actual current climatic conditions. The proposed method and approach to the analysis of the efficiency of the refrigeration capacity regulation of the ACS compressor by distributing the overall range of changes in current heat loads allows increasing the efficiency of utilizing the installed refrigeration capacity in prevailing climatic conditions.
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Radchenko, M., E. Trushliakov, A. Radchenko, S. Kantor, V. Tkachenko, М. Радченко, Є. Трушляков, А. Радченко, С. Кантор, and В. Ткаченко. "Approach to enhance the energetic efficiency of air conditioning systems by cooling load distribution in ambient air procession." Thesis, 2020. http://eir.nuos.edu.ua/xmlui/handle/123456789/4346.
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Approach to enhance the energetic efficiency of air conditioning systems by cooling load distribution in ambient air procession = Підхід до підвищення енергетичної ефективності систем кондиціювання повітря шляхом розподілу холодопродуктивності при обробці зовнішнього повітря / M. Radchenko, E. Trushliakov, A. Radchenko, S. Kantor, V. Tkachenko // Матеріали XI міжнар. наук.-техн. конф. "Інновації в суднобудуванні та океанотехніці". В 2 т. – Миколаїв : НУК, 2020. – Т. 1. – С. 490–500.У загальному випадку весь діапазон холодопродуктивності будь-якої системи кондиціювання повітря включає нестабільний діапазон і порівняно стабільну частину холодопродуктивності для подальшого охолодження повітря. Таким чином, стабільний діапазон холодопродуктивності може бути забезпечений роботою звичайного компресора, в той час як режим із значними коливаннями холодопродуктивності вимагає її модуляції. Пропонований підхід може бути використаний для проектування систем зі змінним потоком хладагента (VRF), забезпечених системою обробки зовнішнього повітря (OAP).
Abstract. In general case, an overall cooling load band of any air conditioning system comprises the unstable cooling load range and a comparatively stable cooling load part for further air cooling. Thus, the stable cooling load range can be covered by operation of conventional compressor, meantime mode with considerable cooling load fluctuation needs load modulation. A proposed method can be adopted for designing Variable Refrigerant Flow (VRF) systems provided with Outdoor Air Processing (OAP) system.
Conference papers on the topic "Refrigeration capacity distribution"
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Broglia, Thomas, Matteo Iobbi, and Nikola Stosic. "Improving the Capacity and Performance of Air-Conditioning Screw Compressors." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-13121.
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Traditional compressor design methods make it very difficult to make significant improvements to screw compressors required for refrigeration and air conditioning applications. The principles which determine the optimum design of such machines are reviewed and, in some cases, redefined. These include rotor profiling, configuration and proportions, clearance distribution and bearing clearances and it is shown that there are conflicting requirements for them when attempting to obtain optimum performance. The best result can thus only be obtained by consideration of all the relevant parameters in an optimisation procedure, which leads to rotor designs that vary according to the specific duty of a machine, rather than follow a standard pattern An outline description is given of a process modelling procedure which has been developed to optimise the design of a compressor by the use of multi variable minimisation methods that take simultaneous account of all these parameters As a result of a collaborative project between industry and an academic institution, this procedure was applied to the design of a new refrigeration screw compressor, which was then built and tested. Its performance was then compared with that of the machine it was intended to replace. It is shown that the optimised design was up to 9% better than the original machine.
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Xueliang, Bai, and Zhou Shaoxiang. "Specific Consumption Analysis of Vapor Compression Refrigeration System." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-70799.
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In real life applications the latest findings of energy savings are playing important role for optimizing and improving the systems. Vapor compression refrigeration systems are some of the most implemented refrigeration systems and most of the energy consumption in this area depends on this system. The power consumption of VCR systems cannot be obtained or compared only with the COP. In order to alleviate the above challenges, a temperature-entropy diagram of actual compression refrigeration cycle is designed to show the differences between the actual and theoretical refrigeration cycles in this research. Second law of thermodynamics was utilized to analyze the entropic and exergy balance of irreversible factors during the refrigeration process. Then specific consumption analysis model of VCR is proposed and specific consumption of specific refrigeration capacity is studied. The proposed method can obtain the actual specific consumption and distribution of the additional specific consumption. Numerical results have shown that the exergy efficiency of the VCR is lower than the COP due to high entropy generation (irreversible losses) because of electricity consumed by the system. An alternative method is introduced for the evaluation of the energy saving potential in VCR system.
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Khan, Muhammad Saad, Sambhaji T. Kadam, Alexios-Spyridon Kyriakides, Ibrahim Hassan, Athanasios I. Papadopoulos, Mohammad Azizur Rahman, and Panos Seferlis. "Comparative Energy and Exergy Analysis of Large Capacity Ammonia-Water and Water-Lithium Bromide Vapor Absorption Refrigeration (VAR) Cycles." In ASME 2021 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/imece2021-71084.
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Abstract District Cooling Plants (DCP) is the sustainable way of energy consumption, refrigeration, and supply of chilled water to end-users via chillers and distribution networks. Thermodynamic assessment of the vapor absorption refrigeration (VAR) in the open literature has been performed for cooling capacity well below the actual requirement (less than 300 kW) of DCP. Therefore, this work aims to investigate energy and exergy analysis of large-scale single effect VAR cycles operated on NH3-water and water-LiBr systems for a cooling capacity of 4000 kW and assess several operating parameters’ influence on cycle performance. Different parameters such as evaporator operating pressure (water-LiBR = 0.010–0.020 atm, NH3-water = 5.39–6.20 atm), chilled water outlet temperature (288–297 K), absorber temperature (300–305 K), condenser temperature (310–315 K), cooling output (2900–4000 kW) and heat input (4300–5500 kW) to the generator are varied during the parametric analysis. The exergy destruction analysis of the cycle’s components is also included in the study. Overall, the COP (0.89) and Exergy efficiency (89%) of water-LiBr were found to be higher than that of an equivalent NH3-water system which is 0.697 and 81%, respectively. The maximum exergy destruction was found at the absorber unit (24%), followed by the generator (23%). Furthermore, the NH3-water and water-LiBr simulations were optimized for different parametric conditions, and optimal operating conditions were identified for large-capacity district cooling systems. Therefore, the findings will provide the roadmap for designing and optimizing large-scale DCP operated on VAR cycles.
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Ranes, Anne, Patrick Phelan, Rafael Pacheco, Anastasios Frantzis, and Lionel Metchop. "Optimization of the Adsorber in an Adsorption Solar-Powered Cooling System." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81833.
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The adsorption solar-powered cooling system is one of several types of solar-powered cooling systems currently under development. Increasing the efficiency and decreasing the cost of this system will make it a commercially viable alternative to traditional refrigeration systems. The objective of this project was to optimize the adsorber in the adsorption system. A mathematical model of the refrigerant distribution within a cylindrical adsorber was developed using equations from Chua et al. [1]. The simulation revealed effects of varying design parameters on the theoretical refrigerant mass flow rate, which is directly proportional to the system refrigeration capacity. These results indicated parameter values to be used in designing the adsorber. It was found that decreased particle radius, decreased bed porosity, increased pipe radius, increased adsorber radius, and increased fin thickness all positively affect the performance of the adsorption system. Further simulation and experimental trials are recommended to verify these results.
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Wei, Jie, Hideo Kubo, and Junichi Ishimine. "Thermal Design and Packaging of a Prototype Refrigeration Cooling System for CMOS-Based MCMs." In ASME 2003 International Electronic Packaging Technical Conference and Exhibition. ASMEDC, 2003. http://dx.doi.org/10.1115/ipack2003-35156.
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Thermal design and packaging strategy of a prototype dual-loop vapor compression refrigeration cooling system, developed as a pilot model for thermal management of high performance CMOS based MCMs, is introduced in this paper. The cooling system was comprised of two separated refrigeration units providing low temperature cooling via a dual-path cooling module (evaporator) mounted on a CPU-MCM package. Cooling capacity for each refrigeration unit was controlled ranging from 250W to 2500W with a refrigerant evaporating temperature at −25 degree centigrade. The CPU-MCM mounted with the refrigeration cooling module was packaged on a system board assembly, together with other electronic devices. The assembly was accommodated into a dew-point control box where two dewpoint control units were operating in a redundancy to remove moisture and keep a dew temperature inside the box below −30 degree centigrade for completely preventing from condensation. Cooling redundancy was provided by both the refrigeration units and dual-path cooling module. The cooling module was redundant in that two sets of refrigerant passages were staggered within a thin copper plate, where each set was connected to a separated refrigeration unit. Apart from the robust system and steady operation, the configuration and operation mode also provided the cooling system a high power efficiency and much shortened starting time. Numerical simulations were also performed for investigating airflow and thermal characteristics, in a system board level inside the dew-point control box. Detailed predictions of airflow and temperature distributions were significantly helpful for improving and verifying practical system designs.
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Li, Haiyan, Lige Tong, Xinxing Sun, Li Wang, and Shaowu Yin. "A Distributed Model for Air-to-Refrigerant Fin-and-Tube Evaporators With Special Emphasis on Two-Phase Zone." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22097.
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A general and simple model for simulating the steady behavior of air-to-refrigerant fin-and-tube evaporators, which accounts for detailed flow state inside the tubes, is introduced. To account for the heat transfer between air and the working fluid, the evaporator is divided into a number of control volumes. Space dependent partial differential equations group is obtained from the mass, energy and momentum balances for each one. The corresponding discretized governing equations are solved afterwards. Empirical correlations are also required to estimate the void fraction, the internal and external heat transfer coefficients, as well as the pressure drops. According to the phase of refrigerating fluid, the evaporator can be divided into two distinct zones on the refrigerant-side: the vapor zone and the two-phase zone, while special emphasis is performed on the treatment of the two-phase zone. The distribution of flow pattern has been evaluated with the aim of improving the calculation accuracy. The model prediction is validated against experimental data for an evaporator using R22 as the working fluid, which shows a reasonable level of agreement: the cooling capacity is predicted within the error band of 3%. The developed model will have wide applications in operational optimization, performance assessment and pipeline design.