跨临界CO_2制冷系统气体冷却器实验研究

Experimental Study of Gas Cooler in Trans-critical CO_2 Refrigeration System

对跨临界CO2制冷系统气体冷却器进行了实验研究。研究表明:随着高压压力的变化,尽管气体冷却器进口的CO2温度与冷却水的换热温差变化范围较大,但气体冷却器出口CO2温度几乎不变;系统的高压压力为9 MPa时,气体冷却器中CO2的压降只有高压压力的1%左右,相对较小;随着气体冷却器出口CO2温度的升高,系统制冷量先呈线性减小,后逐渐趋于稳定,压缩机耗功呈线性增加;实验条件下,气体冷却器出口CO2温度由30℃增至37℃时,系统的COP减小了约25%。

In this paper, the gas cooler in trans-critical CO2 refrigeration cycle system is studied experimentally. Research shows that： the temperature different between the inlet CO2 and the cooling water changes in a wide range as the heat rejection pressure changes, but the outlet CO2 temperature of the gas cooler is almost unchanged; the relative pressure drop is only about 1% when the heat rejection pressure is 9MPa in the system; with the increase of the outlet temperature of the gas cooler, the refrigeration effect decreases linearly first, and the latter becoming more and more stable, but the compression work is linearly increased; on the experimental conditions, the COP decreased about 25% when the outlet temperature of the gas cooler ranged from 30℃ to 37℃.