不同除霜周期对空气源热泵运行性能影响的实测研究
Influence of different defrosting cycles on operating performance of air-source heat pumps
摘要:
为探究不同除霜周期对空气源热泵运行性能的影响,并寻求不同结霜工况下的最佳除霜周期,针对北京地区4种不同结霜工况,分别采用5种不同除霜周期对机组进行实测研究。实测研究在环境温度-2.1~5.6 ℃(平均1.8 ℃)、相对湿度48%~88%(平均68%)、回水温度设定值40 ℃的运行工况下进行,结果表明:在同一结霜工况下,机组存在最佳除霜周期,在不同结霜工况下,机组的最佳除霜周期会发生变化;采用最佳除霜周期控霜时,名义结除霜损失系数为24%~36%,名义有效供热系数可达0.69~0.78,平均性能系数保持在2.06~2.30,机组运行性能显著优于其他除霜控制周期。
Abstract:
To investigate the influence of different defrosting cycles on the operating performance of air-source heat pump (ASHP) and find out the optimal defrosting cycle under different frosting conditions, tests the performance of ASHP with five different defrosting cycles under four kinds of frosting conditions in Beijing. Conducts the field tests under the condition of -2.1 to 5.6 ℃ of environmental temperature with an average temperature of 1.8 ℃,48% to 88% of relative humidity with an average of 68% and 40 ℃ of return water temperature. The results show that there exists an optimal defrosting cycle under the same condition, and it changes with the different conditions. In the optimal defrosting cycles, nominal frosting-defrosting loss efficiency is in the range of 24% to 36%, nominal heating coefficient and average COP are between 0.69 to 0.78 and 2.06 to 2.30 respectively. The performance of ASHP can be significantly improved in optimal defrosting cycles.
Keywords:air-sourceheatpump(ASHP),optimaldefrostingcycle,nominalfrosting-defrostinglossefficiency,nominalheatingcoefficient,averagecoefficientofperformance