Comparison of Borehole Thermal Resistance Values of Ground Heat Exchanger Obtained by Several Methods

Abstract:

The Ground-Coupled or Source Heat Pump (GCHP/GSHP) system is increasingly being considered as an alternative to traditional cooling/heating system because it can reduce the emission of greenhouse gases. The GCHP/GSHP system uses sustainable ground temperature to emit heat during the summer and to extract heat during the winter. It is a ubiquitous system because it can be used at any time or place and semi-permanent energy. The geothermal system is composed of Ground Heat Exchanger (GHE), heat pump and load facilities. The GHE is embedded in a borehole, which is made up of GHE and grout. The borehole thermal resistance is the most important parameter in designing the geothermal system because it shows the quantity of heat transfer in the borehole. There are many methods to estimate the borehole thermal resistance. Thermal Performance Tests (TPTs) were conducted to directly measure the borehole thermal resistance of several kinds of GHEs. Then the experiment results and analytical results were compared in order to select the most accurate methods to evaluate the borehole thermal resistance.

• Periodical: Advanced Materials Research (Volumes 732-733)
• Pages: 103-108
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.732-733.103
• Online since: August 2013
• Authors: Han Byul Kang*, Seok Yoon, Gyu Hyun Go, Seung Rae Lee
• Keywords: Borehole Thermal Resistance, Geothermal Energy, Ground Heat Exchanger (GHE), Heat Transfer, Thermal Performance Test, Vertical Closed Loop

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