STUDY ON HEAT TRANSFER EFFECT OF SINGLE U-SHAPED BURIED PIPE HEAT EXCHANGER IN KARST AREA

doi:10.19912/j.0254-0096.tynxb.2021-0602

Abstract

Abstract: Due to the abundant groundwater in the karst area of south China,the heat transfer capacity of buried pipes can be improved by seepage of multiple aquifers. In this paper,the three-dimensional numerical model of a single U-shaped heat transfer hole was established by using finite element software,and the heat transfer effect of the ground source heat pump system with or without aquifer was analyzed respectively by relevant indexes. The results show that the average outlet temperature of U-shaped pipe shows N1>A1>A2>AF1>AF2 when there is no aquifer in the energy storage rock and soil. The average heat transfer rate per meter under the condition of AF2, AF1,A2 and A1 is 49.87%,44.06%,39.51% and 31.93% higher than that in N1 respectively. The average COP of AF2,AF1,A2 and A1 is 4.35%,3.93%,3.52% and 2.67% higher than that of N1 respectively. Heat exchange holes should be reasonably arranged in areas with abundant groundwater to improve the operating efficiency of the heat pump system. This work can provide certain guidance for practical engineering projects.

Key words: ground source heat pump, heat exchanger, groundwater seeoage, fracture water flow, coefficient of performance

摘要： 以南方岩溶地区地下水丰富为前提,利用多含水层渗流提高地埋管的换热能力。该文利用有限元软件建立三维单U型换热孔数值模型,利用相关指标分析有无含水层时地源热泵系统的换热效果研究。结果表明：蓄能岩土体内有无含水层多种情况时,U型管出水口平均温度呈现N1>A1>A2>AF1>AF2;AF2、AF1、A2和A1情况下的平均延米换热量分别比N1高49.87%、44.06%、39.51%、31.93%;AF2、AF1、A2和A1情况下的平均COP分别比N1高4.35%、3.93%、3.52%、2.67%。在地下水丰富区域应合理布置换热孔,提升热泵系统运行效率,对实际工程项目可提供一定的指导。

关键词: 地源热泵, 换热器, 地下水渗流, 裂隙流, 性能系数

CLC Number:

TK52

Yang Bin, Pei Peng, Luo Tingting, Hao Dingyi, Wang Chen. STUDY ON HEAT TRANSFER EFFECT OF SINGLE U-SHAPED BURIED PIPE HEAT EXCHANGER IN KARST AREA[J]. Acta Energiae Solaris Sinica, 2022, 43(12): 510-519.

杨斌, 裴鹏, 罗婷婷, 郝定溢, 王沉. 岩溶地区特殊地质条件对U型地埋管换热器的传热影响研究[J]. 太阳能学报, 2022, 43(12): 510-519.

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