Rock-soil thermal physical parameter calculation based on line heat source model

Obtains the original test data by in-situ thermal response test from a ground-source heat pump project in Wenzhou. Based on the line heat source model, calculates the rule of heat conduction coefficient and heat capacity per unit volume of soil changing with the test time using slope method and non-linear curve fitting method respectively, and analyses the influence of the initial test data on the result of calculation by non-linear curve fitting method. The results indicate that the slope method has the same stability as the non-linear curve fitting method, but its calculation results deviate from the recommended values greatly. The non-linear curve fitting method is less affected by the initial test data, and the calculation results are close to the recommended range. There is a deviation between the soil thermal physical parameters obtained by in-situ thermal response test and the recommended range in the areas rich in groundwater.