Study On Simultaneous Thermal Response Apparatus For Parameters Of The Rock-soil Thermal Properties And Test Condition

The parameters of the rock-soil thermal properties because of significant changes have decisive influence on the design of ground-source heat pump system. The low operating efficiency and under-capacity is related to irrational design in ground-source heat pump system application.At present, the response test is a more applied method to obtain parameters of the rock-soil thermal properties. In this paper, the test system which two vertical testing exchangers were tested simultaneously was improved on conventional electric heater or air source heat pump as power. The merit and demerit between this system and conventional system were analyzed mainly. Then the design calculation of the new apparatus was achieved.Because of the result of thermal-physical properties tester be testing is not parameter of the rock-soil thermal properties but the temperatures of vertical U-tubes in steady heat-flow, needing a theory of computation based on vertical ground heat exchanger model. In this paper, the analytical solution based on line-source model and cylindrical heat source model was solved, then thermal-physical properties utilized by slope method and parameter estimation method were obtained.The accuracy and Communication of test dates by in-situ response test is poor, because of detailed test introduce is not yet established at the moment. Aiming at this situation, the author Compare the merit and demerit of current design methods, selecting the optimum design and design software according to the design request and Software features. For in-situ test details, focus on determination of initial average temperature of the rock-soil, test time and the effects of the factors, such as transfer temperature differences, physical property of circuit fluid, circulation velocity and the size of the buried tube.etc, on the result of the test result, in order to provide references for standardized test. Then parameter was calculated and modified with related literatures.In a word, this paper focus on testing instrument for in-situ response test, counting principle of parameter of the rock-soil thermal properties based on test dates, and the application condition of response test, make contributions to realize the in-situ response test standardization and parameter modification.