Interpretation of thermal response tests for a borehole heat exchanger system

Category Other
Group GSI.IR
Location International Geological Congress,oslo 2008
Author Shim, Byoung Ohan; Lee, Choon-Ki
Holding Date 07 October 2008

In order to design optimal borehole heat exchanger system the measurement of in-situ thermal conductivity of ground is very important. In this study we conducted several thermal response tests (TRTs) and compared with the results of laboratory test from rock core samples. The test site is located in Daejeon city, Korea. We calculated several thermal conductivity values from TRTs with different injection powers of 2kW and 10kW, and the application of horner plot method. Each interpretation method has pros and cons and can be applied to various situations. We used fiber optic sensing method to monitor ground temperature variation during TRT period. To evaluate the effect of ground water flow to thermal conductivity of the ground we simulated heat exchange rate and heat transfer with a developed numerical model in the case of TRT by pumping of ground water.