Development And Application Research Of Testing Platform Of Shallow Geothermal Energy Thermal Response Tester

The Chinese economy developed rapidly, the demand and supply contradiction ofenergy is more and more apparent. At the same time, the environment is becoming moreand more serious, and sustainable development of our society is seriously threat.Shallow geothermal as a renewable energy had gradually attracted people attention.With the rapid development of ground source heat pump technology, problems inthe system increased, and the system did not match the load in a lot of ground sourceheat pump projects. The main cause is the lack of more accurate thermal propertiesparameters of rock and soil in the design. Therefore, the accurate thermal propertiesparameters of rock and soil are one of the key issues of ground source heat pumptechnology to solve. At present, it is agreed that the thermal response test is an effectivetechnological measure to obtain thermal physical properties of rock and soil. Themethod used the ground heat exchanger system and adopted the artificial cold (hot)source for continuous heating (cooling) in the rock and soil mass and recorded thetemperature change and the flow of heat transfer medium to measure the thermalconductivity.Thermal response test is mainly done by thermal response test instrument, ourcountry has many units to develop a thermal response test instrument. But all testinstruments are in a state of independent research and application, and there is nothird-party certification or relevant standard for the test results. Many thermal responsetester have a problem in accuracy, reliability, etc. In order to control the product quality,test the product performance and ensure the sound development of the industry,scientific testing and measurement are required for the performance of thermal responsetest equipment. If the standard heat exchanger is used for the testing of thermal responsetester, it will be affected by rainfall, temperature change and other conditions, andthermal physical parameters of the heat exchanger will vary with the change in externalconditions, that is, the actual heat exchanger is not standard. To test the accuracy of thermal conductivity of geotechnical thermal response tester,a performance testing platform of shallow geothermal thermal response tester wasdesigned on the basis of line heat source model and in combination with the basicprinciples of heat transfer. The testing platform could be used to simulate ground heatexchangers with different parameters and achieve the online precision testing of thethermal response tester as well as the testing and certification on the accuracy of thermalconductivity. The ground heat exchanger and the testing platform were respectivelyused to test five different types of thermal response test equipment, compare and verifythe reliability of the testing platform, and the developed platform was applied to test theperformance of one thermal response tester. The results showed that the testing platformcould replace the heat exchanger for online performance testing of the thermal responsetest equipment. The thermal response tester had conforming accuracy and the thermalconductivity error was1.4%. By testing the thermal response tester’s precision and theerror of the thermal conductivity, the basis is provided for improving the designaccuracy of heat exchanger.