A transient technique for in-situ thermal property measurements

Abstract

A technique was developed to measure in-situ thermal properties effectively. It makes use of the early transient temperature behavior at the borehole wall in response to the constant heat supply in the borehole. The use of early phase is appropriate since the assumption of cylindrical radial heat flow holds with a good accuracy. To determine the thermal properties of the medium, the theoretical temperature behavior in the Laplace domain was compared with the measured temperature behavior transformed into the Laplace domain. Field data from Avery Island was used for practical application. The obtained thermal properties were subsequently substituted in the nondimensional result given by Carslaw and Jaeger and also used as input parameters in a finite element analysis. The measured temperature behavior was closely reproduced.