竖直地埋管换热器的结构改进与性能试验

肖益民¹, 刘希臣², 张华廷¹, 付祥钊¹

(1.三峡库区生态环境教育部重点试验室(重庆大学), 400045 重庆; 2.中国建筑西南设计研究院有限公司, 610041 成都)



摘要:

为了改进竖直埋管岩土换热器型式的换热性能,提出减小换热器热阻的结构改进设计方案,由三根进水管和一根较大管径的保温出水管构成．推导了结构改进后的换热器热阻理论计算式,计算结果表明,改进后换热器的热阻值比单U和双U型明显减小．在深度约96 m的钻孔内对改进型换热器和单U型、双U型换热器进行了多组加载热负荷试验, 结果显示: 改进后换热器的热阻比单U型减小29%～34%,比双U型减小10%～15%；系统循环水温升比双U型平均小1.5 ℃,换热性能有较明显提高．

关键词:  地埋管换热器  土壤源热泵  热阻  温升

DOI：10.11918/j.issn.0367-6234.2015.02.017

分类号:TK02

基金项目:国家自然科学基金(51178482).



Contrast experiments on three different types of underground heat exchangers of GSHP system

XIAO Yimin¹, LIU Xichen², ZHANG Huating¹, FU Xiangzhao¹

(1.Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment(Chongqing University), Ministry of Education, 400045 Chongqing, China; 2.China Southwest Architectural Design and Research Institute Co.,Ltd. 610041Chengdu, China)

Abstract:

Based on the deficiencies of existing ground heat exchangers, a new type energy-storage heat exchanger is proposed, which consists of three inlet pipes and one thermal insulation outlet pipe. Thermal resistance of this new type heat exchanger is calculated, which shows a much smaller value over conventional ones. Experimental measurements to evaluate the performance of single-U, double-U and the new design, were carried out in boreholes about 96 meters deep, which showed superior performance of the new type. The thermal resistance of the new type was 29%-34% and 10%-15% smaller than that of single-U and double-U respectively. The circulation water temperature rise of new type was 1.5 ℃ lower than double-U.

Key words:  underground heat exchangers  GSHP  thermal resistance  temperature rise