三种中高温热泵工质循环性能实验研究

采用改进型的循环性能对比实验评价研究方法,在水-水蒸汽压缩式热泵实验台上,对理论循环性能优良、样品可得的混合工质M3、M4和纯质HFC245fa,在冷凝温度90～95℃、蒸发温度40～65℃的工况范围内进行了循环性能对比实验研究.研究结果表明,与在冷凝温度90～100℃工况范围内实验性能较优的纯质HFC245fa相比,M3和M4的制热量和COP均明显高于HFC245fa,排温比HFC245fa高10℃左右,综合性能优于HFC245fa;两种混合工质中,M3的环境特性和循环性能最优.

MEASURED PERFORMANCES OF THREE WORKING FLUIDS IN MODERATELY HIGH-TEMPERATURE HEAT PUMPS

The performances of zeotropic mixtures of M3 and M4 and pure fluid HFC245fa were investigated experimentally at condensing temperatures of 90℃and 95℃,with various temperature lifts from 30 to 50℃.The measurements were carried out with a real-sized water-to-water vapor compression heat pump employing the improved approach for comparative evaluation on experimental performances of working fluids.Results show that M3 and M4 offer higher heating capacities and higher COPs,but 10℃ higher discharge temperatures than HFC245fa ever regarded as a suitable working fluid for the condensing temperature range of 90℃ to 100℃.Compared with M4,M3 presents an excellent environmentally friendly cycle performance.