R404A直接接触凝结制冷循环的性能分析

提出R404A直接接触凝结换热的制冷循环,分析R404A直接接触凝结制冷循环的热力性能,并与常规双级压缩制冷循环的性能进行对比。得出结论:在一定的冷凝温度、蒸发温度和过冷液体的过冷度下,直接接触凝结制冷循环存在最佳的饱和液体温度,并在此最佳的饱和液体温度下,获得最优的性能和最小的冷凝热负荷,随着过冷液体的过冷度增大和蒸发温度升高,直接接触凝结制冷循环的性能系数增加、冷凝热负荷减少,获得最优性能的最佳饱和液体温度值提高。过冷液体的过冷度为25℃时,直接接触凝结制冷循环的最佳性能系数较双级压缩制冷循环的最佳性能系数提高6.2%。直接接触凝结制冷循环的最小冷凝热负荷较双级压缩制冷循环的最小冷凝热负荷减小1.8%。

Analysis on performance of R404A direct contact condensation refrigeration cycle

The direct contact condensation refrigeration cycle of R404A is designed.The thermal performances of this R404A direct contact condensation refrigeration cycle are analyzed and compared with that of convention two stage compression refrigeration cycle.It is found that at a certain evaporating temperature,condensation temperature and super cooling degree of supercooled liquid,direct contact condensation refrigeration cycle has the optimum saturated liquid temperature.At the optimum saturated liquid temperature,the coefficient of performance (COP) of the direct contact condensation refrigeration cycle reaches the maximum and the condenser heat load is the minimum.With the increasing of the super cooling degree of supercooled liquid and evaporating temperature,the coefficient of performance (COP) of direct contact condensation refrigeration cycle increases,the condenser heat load reduces,and the optimum saturated liquid temperature(at that temperature the maximum performance is obtained)rises.when the super cooling degree of supercooled liquid is 25 ℃,compared with that of conventional two stage compression refrigeration cycle,the maximum coefficient of performance (COP) of direct contact condensation refrigeration cycle increases by 6.2％,the minimum condenser heat load of direct contact condensation refrigeration cycle reduces by 1.8％.