跨临界CO2两相流引射制冷系统性能实验研究

对跨临界CO2两相流引射制冷系统性能进行了实验,分析了工况及引射器几何参数对系统性能的影响,结果表明:在实验工况范围内,跨临界CO2两相流引射制冷系统制冷量和COP随气体冷却器压力的升高而升高,随气体冷却器出口温度的升高而降低。对于使用不同喉部直径喷嘴的系统,在相同工况下,引射器喷嘴喉部直径较大的系统的性能较好。对于使用不同直径混合室的系统,随着气体冷却器压力的升高,使用小直径混合室的系统COP变化较大;当气体冷却器压力较低时,使用大直径混合室的系统COP较高,而当气体冷却器压力较高时,使用小混合室直径的系统性能较好。在相同工况下,与传统跨临界CO2循环进行比较,两相流引射制冷循环系统COP最大可提高14%。

Experimental Investigation on the Performance of the Transcritical CO2 Two-phase Ejector Refrigeration Cycle

Experimental studies on the transcritical CO2 two-phase ejector refrigeration cycle were carried out, and the effects of the working conditions and the geometric parameters of the ejector on the performance of the system were analyzed. The experiment results indicate that the COP and cooling capacity of the system increase with the rise of the cooling pressure, while decrease with the increase in the outlet temperature of the gas cooler. For the systems using different throat diameter of the nozzles, the COP of the system using the larger throat diameter of the nozzle is larger than that using the smaller one under the same condition. For systems using different diameter mixing chambers of the ejector, with the increase in the cooling pressure, the COP of the system using the smaller diameter of the mixing chamber varies greatly, and is lower than that of the system using the larger one under the lower cooling pressure condition. While under higher cooling pressure condition, the performance of system using smaller diameter of the mixing chamber is better. The COP of the transcritical CO2 refrigeration cycle with a two-phase ejector is increased by 14% comparing to the traditional cycle at the same condition.