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http://dx.doi.org/10.7843/kgs.2013.29.10.49

Evaluation of Borehole Thermal Resistance in Ground Heat Exchanger  

Yoon, Seok (Graduate Student, Dept. of Civil and Environmental Eng., KAIST)
Lee, Seung-Rae (Graduate Student, Dept. of Civil and Environmental Eng., KAIST)
Kang, Han-Byul (Graduate Student, Dept. of Civil and Environmental Eng., KAIST)
Go, Gyu-Hyun (Graduate Student, Dept. of Civil and Environmental Eng., KAIST)
Kim, Min-Jun (Graduate Student, Dept. of Civil and Environmental Eng., KAIST)
Shin, Ho-Sung (Dept. of Civil and Environmental Eng., Univ. of Ulsan)
Publication Information
Journal of the Korean Geotechnical Society / v.29, no.10, 2013 , pp. 49-56 More about this Journal
Abstract
The use of geothermal energy has been increased for economic and environmental friendly utilization. Ground thermal conductivity and borehole thermal resistance are very important parameters in the design of geothermal heat pump system. This paper presents an experimental study of heat exchange rate of U and W type ground heat exchangers (GHEs) measured by thermal performance tests (TPTs). U and W type GHEs were installed in a partially saturated dredged soil deposit, and TPTs were conducted to evaluate heat exchange rates under 100-hr continuous operation condition. The heat exchange rates were also calculated by analytical models to estimate borehole thermal resistances and were compared with experimental results. It comes out that multi-pole and equivalent diameter (EQD) models resulted in more accurate agreement than shape factor (SF) model which is currently more often used.
Keywords
Ground heat exchanger; Heat exchange rate; Borehole thermal resistance; Multi-pole model;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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