Research On The Laws Of Moisture Soil Heat And Moisture Transfer Sensitivity

With the advent of the global energy crisis and environmental problems,a use of renewable energy efficient green energy saving, pollution-free both winter heating and summer cooling of ground source heat pump air conditioning new technology is developing rapidly. The shallow ground source heat pump technology is an effective way for geothermal energy utilization,and has a good economy,and underground heat storage is used widely. Researching on the laws of moisture soil heat and moisture transfer sensitivity has an important engineering practical significance for the optimization design of underground heat storage system.In this paper, a one-dimensional experimental setup is established for moisture soil heat and moisture migration. On the basis of the physical properties and hydrodynamic properties theoretical and experimental test of moisture soil, the laws of moisture soil heat and moisture transfer sensitivity is analyzed under the condition of different initial volume moisture content, and focuses on analyzing the gravity of moisture in the soil. Heat conduction model and heat and moisture transfer model is established on the basis of the experiment, and through the finite volume method for solving based on the Fluent.The results show that the moisture migration is not obvious under the condition of low temperature heat storage, and leads to the physical properties of the soil changed small.As a result, three models of data result error is smaller. But under the condition of high temperature thermal storage moisture migration makes the heat and mass transfer effect of strong coupling,and makes great changes of soil physical properties. Especially near the heat source, moisture migration showed obvious sensitivity regularity. When the initial volume moisture content is less than 15%(the initial saturation within 40%), Temperature field is rising with the increase of initial moisture,and moisture migration is very significant under the effect of temperature gradient near the heat source within 15 cm.In the initial saturation within 40%, the gravity of the moisture migration has little effect on temperature field for soil thermal storage. When the initial volume moisture content is less than 25%(the initial saturation within 67%), Temperature is gradually increasing with the increase of moisture content and good for the heat storage of the soil. More than 25% the soil temperature field increase is not obvious with the increase of moisture content. Under the condition of high moisture content, Soil moisture evaporation diffusion condensation migration process caused by temperature and temperature gradient is significantly weakened, and the energy transfer caused by moisture migration is not obvious.