A Study on the Thermal Characteristics of Horizontal Ground Heat Exchanger using Thermal Response Test

Title & Authors
A Study on the Thermal Characteristics of Horizontal Ground Heat Exchanger using Thermal Response Test
Chang, Keun Sun; Kim, Min-Jun; Kim, Young-Jae;

Abstract
Vertical and standing column well ground heat exchangers have mostly been installed for ground source heat pump systems (GSHP) and thermal response tests (TRT) have been applied to evaluate the thermal characteristics for these heat exchangers. In this paper, the TRT coupled with a line source method was applied to evaluate the thermal characteristics of the horizontal ground heat exchanger (HGHX). Load tests of a HGHX were also performed to examine the daily variations of the ground and fluid temperatures associated with the daily intermittent operation of GSHP. For this test, the straight HGHX (depth 2 m, length 50 m, 8 line) was installed in Ansan city. The results showed that the variations of ground thermal conductivity of HGHX during one year were relatively small with the range of $\small{1.43{\sim}1.64W/m{\cdot}K}$, and the maximum and minimum values appeared in December and May, respectively. Load tests with heat injection rate of 6.0 kW for 10 hours per day to HGHX during twelve days were performed in June, September and December, and resulted in a ground initial temperature rise of $\small{4.31^{\circ}C}$, $\small{3.14^{\circ}C}$, and $\small{1.21^{\circ}C}$ during these days, respectively.
Keywords
Thermal response test(TRT);Ground thermal conductivity;Horizontal ground heat exchanger(HGHX);Ground source heat pump system(GSHP);
Language
Korean
Cited by
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