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Prediction of Ground Thermal Properties from Thermal Response Test

현장 열응답 시험을 통한 지중 열물성 추정

Yoon, Seok;Lee, Seung-Rae;Kim, Young-Sang;Kim, Geon-Young;Kim, Kyungsu
윤석;이승래;김영상;김건영;김경수

  • Received : 2016.04.04
  • Accepted : 2016.06.21
  • Published : 2016.07.31

Abstract

The use of geothermal energy has increased for economically and environmentally friendly utilization, and a geothermal heat pump (GSHP) system for space heating and cooling is being used widely. As ground thermal properties such as ground thermal conductivity and ground thermal diffusivity are substantial parameters in the design of geothermal heat pump system, ground thermal conductivity should be obtained from in-situ thermal response test (TRT). This paper presents an experimental study of ground thermal properties of U and 2U type ground heat exchangers (GHEs) measured by TRTs. The U and 2U type GHEs were installed in a partially saturated dredged soil deposit, and TRTs were conducted for 48 hours. A method to derive the thermal diffusivity as well as thermal conductivity was proposed from a non-linear regression analysis. In addition, remolded soil samples from different layers were collected from the field, and soil specimens were reconstructed according to the field ground condition. Then equivalent ground thermal conductivity and ground thermal diffusivity were calculated from the lab test results and they were compared with the in-situ TRT results.

Keywords

Thermal response test;Ground thermal conductivity;Ground thermal diffusivity;Non-linear regression anlaysis

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Cited by

  1. A Prediction of Specific Heat Capacity for Compacted Bentonite Buffer vol.15, pp.3, 2017, https://doi.org/10.7733/jnfcwt.2017.15.3.199

Acknowledgement

Supported by : 한국연구재단