空气与土壤复合源热泵在北方地区的匹配设计模拟分析

空气与土壤复合源热泵系统通过空气换热器实现了间接空气源热泵模式与补热模式,可补偿取、放热量的差值,解决土壤源热泵系统在我国北方地区长期运行产生的土壤热不平衡问题。为能够在保障供暖效果的前提下最大限度地降低地埋管数量,本文以我国5个北方城市的住宅为例,在TRNSYS平台上建立了空气与土壤复合源热泵系统的仿真模型,对地埋管和空气换热器的匹配设计进行了研究,并对减少地埋管数量后的复合源热泵系统的应用效果进行了模拟分析。结果表明:复合源热泵系统在哈尔滨、长春、沈阳、北京、济南的地埋管数量最大减少比例为29%~43%,每延米地埋管需对应匹配0.029~0.050 m²的空气换热器面积;减少地埋管数量后的复合源热泵系统在长期运行中可维持土壤温度稳定,其十年总费用节省率为12.6%~25.3%。

Performance Simulation of Air-ground Hybrid Source Heat Pump Systems in Northern China

The air-ground hybrid source heat pump system can realize indirect air-source heat pump mode and heat compensation mode through an air-water heat exchanger,which could compensate for the difference between heat extraction and heat injection to the soil.This could solve the problem of soil heat imbalance caused by the long-term operation of the ground-source heat pump system in northern China.In this study,the residential buildings in five cities of northern China were used as examples and a model of air-ground hybrid source heat pump system was established on the TRNSYS platform.To minimize the number of ground heat exchangers and ensure a good heating effect,the matching design of ground heat exchangers and air-water heat exchangers was explored and the performance and reduced number of ground heat exchangers of the air-ground hybrid source heat pump system were simulated and analyzed.The results showed that the maximum reduction ratios of the ground heat exchangers in Harbin,Changchun,Shenyang,Beijing,and Jinan were 29%-43%,and 0.029-0.050 m² of air-water heat exchangers were needed per linear meter of ground heat exchangers.The air-ground hybrid source heat pump system with a reduced number of ground heat exchangers could provide a stable soil temperature during a long-term operation.Its total cost saving rates for ten years were 12.6%-25.3%.