基于R124/DMAC为工质的压缩吸收式制冷系统的性能分析

摘要

Absorption refrigeration can recover industrial waste heat,but cannot effectively utilize waste heat below 100℃.Aiming at the problems of high pressure and temperature in the traditional ammonia absorption refrigeration system,the performance of compressive absorption refrigeration system was simulated with R124/DMAC as working fluids.Operating parameters were studied by changing operating temperatures,pressures and condensing temperatures.Operating temperature and pressure were the major factors influencing system COP,energy loss and efficiency.Compared with the traditional ammonia absorption refrigeration system,the results showed that at the same condensing temperature,the maximum COP of the two working fluid systems was the same.But the new system had a lower pressure of 600kPa (ammonia system of 1100kPa),a lower temperature of 75 ℃ (ammonia system is 100℃).The irreversibility using the new refrigerant and the exergy efficiency were in a reasonable range.The main factors influencing the system of COP,exergy loss and exergy efficiency were pressure,temperature and condensing temperature.%吸收式制冷能够利用工业余热进行制冷,但存在不能高效利用100℃以下废热的问题.本文以压缩吸收式制冷系统为研究对象,采用新型制冷工质对R124/DMAC,对不同发生压力、发生温度和冷凝温度下系统性能的变化规律进行研究,并与传统氨/水制冷系统的性能进行比较.结果表明影响系统制冷系数(COP)、(火用)损和(火用)效率的主要因素是发生温度和发生压力,在相同冷凝温度下,R124/DMAC制冷系统的最佳发生压力为600kPa,最佳发生温度为75℃;而氨/水制冷系统的最佳发生压力为1100kPa,最佳发生温度为100℃,采用新型制冷工质对能够有效地利用更低品位的热源进行制冷,同时系统的安全性更高.