Research And Implementation Of Geotechnical Thermophysical Property Tester

With the pollution of living environment and the depletion of fossil energy sources,the development and utilization of renewable clean energy sources have attracted the attention of governments.Geothermal energy is a clean,environmentally friendly and pollution-free energy source.Among them,the ground source heat pump is the main method of exploiting geothermal energy,and the accuracy of geophysical thermal physical parameters is an important indicator for designing the ground source heat pump.In order to obtain accurate geophysical and thermophysical parameters,this subject independently developed a geotechnical thermophysical property tester based on the field thermal response principle and applied it to actual project engineering.The geotechnical thermophysical property tester is mainly composed of circulation system,heating system,data acquisition system and display control system.The power of the tester is adjusted by stepless power regulation,which can meet the power requirements of drilling at different depths.According to the control logic of the tester,display and control human-computer interaction software is developed to realize the real-time data display,monitoring and storage of temperature,flow and power.At the same time,related researches on heat transfer model and data processing of rock and soil were made.The detailed calculation process of the models inside and outside the borehole is given.In the data processing,the dual-parameter estimation method combined with Nelder-Mead simplex algorithm was used to develop the calculation software for geophysical and thermal properties.Taking the actual project as an example,the boreholes on the construction site were tested in the field,and the collected data were calculated to obtain the geophysical and thermal parameters of the area.Therefore,the research of this topic has certain engineering practical value for the investment of ground source heat pumps,and also plays a positive role in protecting the environment and using clean geothermal energy.This project was commissioned by Beijing Survey and Design Institute to conduct joint research and development.