【摘要】 建立了考虑土壤冻结的地埋管换热器非稳态传热模型,采用有限容积法离散了管内流体、管壁及土壤区域的控制微分方程,对涉及的土壤相变问题采用显热容法处理。数值计算结果表明,地埋管换热器周围土壤冻结区域较小,但土壤冻结后导热系数大幅度提高,更有利于土壤的导热;考虑土壤冻结的影响后,计算出的地埋管换热器的出水温度和取热量均有所提高;土壤含水量高有利于地埋管换热器的换热,但土壤含水量较低时,土壤冻结对地埋管换热器性能的影响较小。更多还原

【Abstract】 Develops a transient heat transfer model considering the soil freezing. With the finite volume method,discretizes the governing differential equations of the fluid,the pipe wall and the soil,and solves the soil freezing problem based on the sensible heat capacity method. The numerical calculating results indicate that the soil freezing region around the ground heat exchanger is small,but the heat conductivity of freezing soil increases largely,which is benefit to the soil heat transfer. When considering the effect of soil freezing,the outlet fluid temperature and the heat extracted from the ground are higher. High soil moisture content is benefit to the heat transfer,but the effect of soil freezing on the performance of ground heat exchanger is small with lower soil moisture content.更多还原