Structure optimization for horizontal ground heat exchanger

• Published in: Applied thermal engineering Vol. 136; pp. 131 - 140
• Main Authors: Pu, Liang, Xu, Lingling, Qi, Di, Li, Yanzhong
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 25.05.2018; Elsevier BV
• Subjects: Buried pipes; Comprehensive parametric analysis; Energy efficiency; Heat conductivity; Heat exchangers; Horizontal ground heat exchanger; Numerical analysis; Numerical simulation; Parameter optimization; Resistance factors; Thermal performance; Thermal resistance; Numerical simulation; Horizontal ground heat exchanger; Comprehensive parametric analysis; Thermal performance
• ISSN: 1359-4311; 1873-5606
• DOI: 10.1016/j.applthermaleng.2018.02.101

•The effects of bending number for buried pipes on thermal performance of HGHE.•Comparison of performance between the staggered and in-line arrangement.•Comprehensive influence of pipe spacing and buried depth were investigated.•The critical pipe spacing of HGHE was obtained. With the advantages of lower installation cost and lower drilling technology requirement, the horizontal ground heat exchanger (HGHE) has attracted much attention. In this paper, the pipe arrangements with in-line and staggered are evaluated comparatively and the effects of the relative displacement of staggered pipes are investigated. Meanwhile, the comprehensive effects of bending number, pipe spacing and buried depth on thermal performance of HGHE are studied. The results show that the thermal performance of staggered arrangement outperformed that of in-line arrangement when the relative offset displacement is greater than 1/3. The thermal interference between adjacent buried pipes is the significant factors causing thermal resistance. For double-layered HGHE, the critical pipe spacing of first layer and second layer is 40d and 100d respectively. The buried depth has little effect on the thermal performance of HGHE.