Conditions and Features of the Occurrence of Shallow Geothermal Energy in Major Cities of Liaoning Province

Abstract:

Change rule for the study of the thermal physical parameters of rock and soil mass can occurrence characteristics of shallow ground temperature,such as using the thermal response test and the research methods such as laboratory test and analysis of geotechnical engineering (thermal conductivity),porosity,thermal conductivity,specific heat,scientific analysis,parameters,such as using IGSHPA line heat source model and INGERSOll cylindrical heat source model to carry out the analysis of characteristics of coefficient of thermal conductivity changes.The results show that the average thermal conductivity of strata in the area is 1.68～3.44W? (m?K)-1,and the high value area is located in bedrock mountainous area.Formation of initial ground temperature range of 10.80～15.80℃,the high value area in east and west on both sides of bedrock mountains and piedmont zone.Under the condition of natural moisture content,the thermal conductivity of the rock and soil body shows an obvious trend with the change of water content,particle density and porosity,that is,it gradually decreases with the increase of water content,increases with the increase of particle density and gradually decreases with the increase of porosity.As the diameter of borehole increases, the thermal conductivity of borehole decreases and the thermal resistance of borehole increases obviously.And the initial temperature of 1.0°as a standard for geothermal recovery,sticky soil layer recovery needs 5d,coarse sand formation in the recovery of 3d; And the initial temperature of 0.5°as a standard for geothermal recovery,sticky soil layer recovery need 15d,coarse sand formation in the recovery period for 7d.