Investigation of the effect of seasonal variation in ground temperature on thermal response tests

Abstract

Economical design of Ground Heat Exchangers (GHEs) relies significantly on accurate estimations of ground thermal properties, including undisturbed ground temperature, ground thermal conductivity, and GHE thermal resistance. Typically these are measured in situ by a Thermal Response Test (TRT), where the parameters are back-calculated by fitting a heat transfer model to the temperature response. The accuracy of most models relies on an assumption of constant ground temperature with depth, but in reality there are several mechanisms by which this may be invalid, one being seasonal variation in ground temperature. In this paper a study of Infinite Line Source Model performance under different ..