一种双制冷温度双工质吸收制冷系统的模拟

Simulation of Absorption Refrigeration System with Double-chilling Temperature and Double-working Pair

在较高的热源温度下 ,吸收制冷系统需采用双效再生流程提高制冷性能系数COP ,从而却使只用氨作为制冷剂的系统再生操作压力大幅度增高。为克服这种缺陷 ,提出了一种新的吸收制冷系统 ,分别以水 -溴化锂和氨 -硝酸锂作为二个系统的工质 ,将二系统耦合组成双制冷温度双工质系统。对该系统的操作性能进行了热力学模拟 ,分析讨论了热源温度、冷却水温度和蒸发器 2蒸发温度对系统操作性能的影响及系统适宜的操作条件。该系统操作稳定 ,在较宽的操作条件下 ,COP可以稳定在 1.10以上 ,与类似条件下只用水 -溴化锂作为工质的系统相当 ,但相应的制冷温度可低至 - 13℃以下 。

The two-stage generation is adopted at higher heating temperature in absorption refrigeration system for higher coefficient of performance (COP), but the generation pressure increases to a great extent only with ammonia as refrigerant. A new absorption refrigeration system was presented for overcoming the shortcoming. Two systems respectively with water-lithium bromide and ammonia-lithium nitrate as working pair were coupled in a system with double-chilling temperature and double-working pair. The operation performance of the system was simulated thermodynamically. The effects of the heating temperature, the cooling-water temperature, the second evaporator temperature, and the feasible operation conditions were analyzed and discussed. The operation is steady for the system, and the COP may retain above 1.10 at wide operation conditions. It corresponds to the system only with water-lithium bromide as working pair at the similar conditions, but the corresponding chilling temperature may retain below -13℃. The system has a good prospect of the development and application.