杨俊兰,姬旭,李金芮,白杨
YAGN Junlan,JI Xu,LI Jinrui,BAI Yang

• 1:天津城建大学能源与安全工程学院

摘要(Abstract)：

为了提高CO_2跨临界热泵系统的性能，通过建立热力学模型，将3种带膨胀机的CO_2跨临界循环，即单级膨胀机循环(SCE)、双级一次节流中间完全冷却循环(TPCE)、双级二次节流中间完全冷却循环(TSCE)与单级节流阀循环(BASE)进行了制热性能对比分析。结果表明：蒸发温度变化时，TSCE循环的制热系数COP_h最大，分别比SCE和TPCE循环平均高出6.32%和10.01%；当气体冷却器出口温度高于37 ℃时，SCE循环的COP_h最大，低于37 ℃时，TSCE性能最好；TPCE和TSCE循环在蒸发温度变化过程中，存在蒸发温度的最优值，对应对基础循环的提升程度ΔCOP最大，TPCE和TSCE循环的ΔCOP最大值分别为27.27%和15.21%；根据假设条件，进而得到了最优高压和蒸发温度和气体冷却器出口温度之间的关联式。
In order to improve the performance of CO_2 transcritical heat pump system，three kinds of CO_2 transcritical cycles with expander，i.e.，single-stage expander cycle(SCE)，two-stage primary throttling intermediate complete cooling cycle(TPCE)，two-stage secondary throttling intermediate complete cooling cycle(TSCE) and single-stage throttle valve cycle(BASE)，were compared and analyzed by establishing thermodynamic model.The results show that the heating coefficient COP_h of TSCE cycle is the highest when the evaporation temperature changes，an increase of 6.32% and 10.01% against that of SCE and TPCE cycle，respectively；When the outlet temperature of the gas cooler is higher than 37 ℃，the COP_h of SCE cycle is the largest，and when the outlet temperature is lower than 37 ℃，the performance of TSCE is the best；There is an optimal value of evaporation temperature in TPCE and TSCE cycles，which has the greatest increase ΔCOP corresponding to basic cycle，and the maximum value of TPCE and TSCE cycles was 27.27% and 15.21%，respectively；According to the assumptions，the correlations between the optimal high pressure and evaporation temperature and the outlet temperature of the gas cooler were obtained.

关键词(KeyWords)： CO_2跨临界循环;膨胀机;系统性能;双级压缩
transcritical CO_2 cycle;expander;system performance;two-stage compression

Abstract:

Keywords:

基金项目(Foundation): 天津市科技特派员项目(16JCTPJC52800)

作者(Author): 杨俊兰,姬旭,李金芮,白杨
YAGN Junlan,JI Xu,LI Jinrui,BAI Yang

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