天府新区红层砂泥岩热响应试验与地温恢复特性研究OA

Shallow geothermal energy is a clean and renewable resource,and field thermal response test can reveal the thermal response characteristics of rock and soil.Taking the Sichuan Tianfu New Area as an example,a thermal response test was conducted of the buried pipe.To study the ground temperature recovery characteristics,the heater was turned off while the circulation pump and data acquisition system continued operating.The monitoring data were used to calculate the thermal conductivity of the rock and soil,verify the accuracy of the rock and soil thermal response test results,and determine the time interval required between two thermal response tests at different heating powers in the red sandstone and mudstone area.Results show that the initial average ground temperature was 19.4℃,with a comprehensive thermal conductivity of 2.83 W·(m·℃)-1.The relative deviation between the thermal conductivity obtained from the field thermal response test and that from the ground temperature recovery test was approximately 12%,indicating reliable test data.Ground temperature recovery mainly occurs in the early stage after heating stops,with the recovery rate gradually decreasing thereafter.