吸收-喷射复合制冷系统热力性能与节能分析

Analysis on thermal characteristics and energy saving of absorption–ejector combined refrigeration system

基于工业余热回收利用,提出了一种吸收-喷射复合制冷系统,对系统建立数学模型并进行热力性能分析,分析了发生温度、蒸发温度、冷凝温度、吸收温度及喷射器效率对系统COP的影响。与传统单效式吸收式制冷系统进行对比,得出了吸收-喷射复合制冷系统COP最大时喷射器压缩比最佳值随发生温度的变化规律。研究表明:吸收-喷射复合制冷系统传统单效吸收式制冷系统可利用更低品位的热源,在热源温度为75℃时仍能正常工作;高、低压喷射器压缩比最佳值随发生温度的升高而降低,并逐渐接近于1,且低压喷射器最佳压缩比总是高于高压喷射器的最佳压缩比,在较低热源温度工况下,吸收-喷射复合制冷系统相比传统单效吸收式制冷系统节能效果显著。

A novel absorption-ejector composite refrigeration system is proposed.The mathematical model is established and the thermal characteristics are analyzed.The effects of temperature,evaporation temperature,condensation temperature,absorption temperature and ejector efficiency on the system COP are analyzed.Gain the change law of the optimum value of the squeezing ratio with generating temperature when the ejector composite refrigeration system COP is the biggest.The results show that the absorption-ejector composite refrigeration system can work with the lower grade heat source compared with the traditional single-effect absorption refrigeration system,the absorption-ejector composite refrigeration system can work at the heat source temperature of 75℃.High and low pressure ejector compression ratio optimal values occurred with the rise of temperature,and gradually close to 1,and the best compression ratio of low pressure ejector is always higher than the high pressure ejector,and in low heat source temperature conditions,absorb-ejector composite refrigeration system compared with the traditional single effect absorption refrigeration system can save energy up.