空气源跨临界CO_2热泵最优排气压力的理论和实验  

Theoretical and Experimental Investigation for Optimal Discharge Pressure of Air-Source Trans-Critical CO_2 Heat Pump

作　　者：宋昱龙 唐学平 王守国[1] 杨东方[1] 曹锋[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049 [2]江苏白雪电器股份有限公司,江苏常熟215500

出　　处：《西安交通大学学报》2014年第9期81-87,共7页Journal of Xi'an Jiaotong University

摘　　要：为了研究空气源跨临界CO2热泵系统中影响最优排气压力的主要因素,以跨临界CO2热泵机组为平台,在焓差室中进行了制热性能测试。结果表明,系统的蒸发压力和气冷器出口温度随排气压力的上升而下降,过热度随排气压力的上升而上升,制热量与制热能效比随排气压力的上升先上升后下降,且存在一个最优值。综合实验数据可以看出,系统的最优排气压力随着环境温度、进水温度、出水温度的下降而降低。在进水温度(环境水温)没有剧烈变动的条件下,通过数据拟合的方法创新性地提出了以环境温度及出水温度为自变量的预测最优排气压力的实验关联式。实验对比证明,系统运行在预测最优排气压力时,制热能效比与实验最优值的偏差小于1.3%,说明以环境温度及出水温度为自变量的预测最优排气压力的方法是值得同行参考的一种有效方法。To reveal the main factors of the optimal discharge pressure in a trans-critical CO2 heat pump system,the heating performance is tested in entha[py difference laboratory.The results show that the evaporation pressure and temperature in gas-cooler outlet decline with increasing discharge pressure; the superheat increases with discharge pressure; the heating capacity and the coefficient of performance （COP） increase firstly and then drop when discharge pressure rises,indicating that an optimal value exists.According to the test data,it is found that the optimal discharge pressure drops with declining environment temperature,inlet water temperature and outlet water temperature.At unchanged inlet water temperature （ambient water temperature）,an experimental correlation taking environment temperature and outlet water temperature as independent variables is constructed by data fitting to predict the optimal discharge pressure.The experiments indicate that the COP difference between predicted optimal discharge pressure and actual optimal discharge pressure is less than 1.3 %.

关 键 词：跨临界CO2热泵 最优排气压力 关联式 

分 类 号：TB61[一般工业技术—制冷工程]