利用工程方程求解器（EES）软件，建立了低温太阳能驱动的有机朗肯?蒸汽压缩制冷系统热力学模型。从HCFC、HFC、HC和HFO中分别选取一种代表性的工质R123、R245fa、R600a和R1234ze(E)，从热力学第一和第二定律角度，兼顾系统换热器的传热能力（UA值），建立了耦合系统效率和投资的目标函数EPUA，研究了发生温度、冷凝温度和蒸发温度对系统热效率、?效率和UA值的影响规律，同时探讨了发生器、冷凝器、蒸发器换热温差对系统UA值和EPUA的影响。结果表明：提高发生温度、降低冷凝温度、提高蒸发温度均可以提高系统的热效率和?效率，但同时也增大了系统的UA值，相应地增加了系统的投资。通过考察系统的EPUA，发现存在最佳的冷凝温度42℃和最佳的蒸发温度4℃。蒸发温度对系统性能的影响要小于冷凝温度的影响，远大于发生温度的影响。4种工质热效率和?效率从大到小依次为R123、R600a、R245fa、R1234ze(E)。在本文研究范围内，从热力学角度分析，R123是最适合的循环工质。系统的UA值随着发生器热水进出口温差的增大先降低后增大，随着冷凝器冷却水进出口温差的增大而增大。蒸发器冷冻水进出口温差对系统的UA值和EPUA的影响可以忽略不计。
A thermodynamic model of low-temperature solar oganic rankine vapor compressor refrigeration system was built by using the Engineering Equation Solver (EES) software. Four working fluids, including R123, R245fa, R600a and R1234ze (E) were preselected from HCFC, HFC, HC and HFO, respectively. The influences of generation, condensation and evaporation temperature on the thermal efficiency, exergy efficiency, the UA value and EPUA (thermal efficiency per UA value), were studied. Further, the effects of heat transfer temperature differences of the boiler, condenser and evaporator on the UA and EPUA were also investigated. The results showed that the thermal efficiency, exergy efficiency and UA value all increased with the increase of generation and evaporation temperature, and decreased with the increase of condensation temperature. There existed an optimal condensation temperature of 42oC and evaporation temperature of 4oC to get a maximal EPUA value. The impact degree of evaporation temperature on system performance was less than that of condensation temperature, greater than that of generation temperature. In terms of the largest thermal efficiency and exergy efficiency, the order went as follows: R123, R245fa, R600a, and R1234ze(E). Analyzing on the basis of thermodynamics, R123 was the most suitable working fluid. The UA value first increased and then decreased with the increase of the heat transfer temperature differences of the boiler. Higher heat transfer temperature differences of the condenser led to higher UA value. The heat transfer temperature difference of the evaporator had little impact on the UA value.
[1] 宋兆培, 王如竹, 翟晓强. 太阳能驱动的高温辐射供冷[J]. 科学通报, 2008, 53(24): 3056-3061.
[2] BALARAS C A, GROSSMAN G, HENNING H M, et al. Solar air conditioning in Europe-an overview[J]. Renewable and sustainable energy reviews, 2007, 11(2): 299-314. DOI: 10.1016/j.rser.2005.02.003.
[3] E?RICAN A N, KARAKAS A. Second law analysis of a solar powered Rankine cycle/vapor compression cycle[J]. Journal of heat recovery systems, 1986, 6(2): 135-141. DOI: 10.1016/0198-7593(86)90073-1.
[4] LI H S, BU X B, WANG L B, et al. Hydrocarbon working fluids for a Rankine cycle powered vapor compression refrigeration system using low-grade thermal energy[J]. Energy and building, 2013, 65: 167-172. DOI: 10.1016/j.enbuild.2013.06.012.
[5] DUBEY M, RAJPUT S P S, NAG P K, et al. Energy analysis of a coupled power-refrigeration cycle[J]. Proceedings of the institution of mechanical engineers, part a: journal of power and energy, 2010, 224(6): 749-759. DOI: 10.1243/09576509JPE894.
[6] APHORNRATANA S, SRIVEERAKUL T. Analysis of a combined Rankine-vapour-compression refrigeration cycle[J]. Energy conversion and management, 2010, 51(12): 2557-2564. DOI: 10.1016/j.enconman.2010.04.016.
[7] 黄允东, 郁永章. 利用涡旋机械的朗肯-朗肯循环制冷系统制冷剂的优选[J]. 流体机械, 1997, 25(1): 52-55, 38.
[8] JEONG J, KANG Y T. Analysis of a refrigeration cycle driven by refrigerant steam turbine[J]. International journal of refrigeration, 2004, 27(1): 33-41. DOI: 10.1016/S0140-7007(03)00101-4.
[9] KAUSHIK S C, SINGH M, DUBEY A. Thermodynamic modelling of single/dual organic fluid Rankine cycle cooling systems: a comparative study[J]. International journal of ambient energy, 1994, 15(1): 37-50. DOI: 10.1080/01430750.1994.9675627.
[10] KAUSHIK S C, DUBEY A, SINGH N. Thermal modelling and energy conservation studies on freon rankine cycle cooling system with regenerative heat exchanger[J]. Heat recovery systems and CHP, 1994, 14(1): 67-77. DOI: 10.1016/0890-4332(94)90073-6.
[11] KARELLAS S, BRAIMAKIS K. Energy-exergy analysis and economic investigation of a cogeneration and trigeneration ORC-VCC hybrid system utilizing biomass fuel and solar power[J]. Energy conversion and management, 2016, 107: 103-113. DOI: 10.1016/j.enconman.2015.06.080.
[12] ANEKE M, AGNEW B, UNDERWOOD C, et al. Thermodynamic analysis of alternative refrigeration cycles driven from waste heat in a food processing application[J]. International journal of refrigeration, 2012, 35(5): 1349-1358. DOI: 10.1016/j.ijrefrig.2012.04.008.
[13] PRIGMORE D, BARBER R. Cooling with the sun's heat Design considerations and test data for a Rankine Cycle prototype[J]. Solar energy, 1975, 17(3): 185-192. DOI: 10.1016/0038-092X(75)90058-4.
[14] WANG H L, PETERSON R, HARADA K, et al. Performance of a combined organic Rankine cycle and vapor compression cycle for heat activated cooling[J]. Energy, 2011, 36(1): 447-458. DOI: 10.1016/j.energy. 2010.10.020.
[15] WANG H L, PETERSON R, HERRON T. Design study of configurations on system COP for a combined ORC (organic Rankine cycle) and VCC (vapor compression cycle)[J]. Energy, 2011, 36(8): 4809-4820. DOI: 10.1016/j.energy.2011.05.015.
[16] LIU W, MEINEL D, WIELAND C, et al. Investigation of hydrofluoroolefins as potential working fluids in organic Rankine cycle for geothermal power generation[J]. Energy, 2014, 67: 106-116. DOI: 10.1016/j.energy.2013.11.081.
