The Operating Performance Analysis Of GSHP With The Heat And Moisture Transfer In Unsaturated Soil

This paper mainly investigates the model of ground heat exchanger (GHE) with heat and moisture transfer in unsaturated soil. The paper establishes the thermal and mass equations of GHE, and gives the numerical calculation procedure of the equations. Then the paper analyses the factors'effect to the temperature and moisture distribution of underground soil from the view of theory. The factors include the initial soil temperature, initial soil moisture, rejection heat. Based on the model, the paper analyses the operating performance of Ground Source Heat Pump (GSHP) system theoretically and experimentally. The paper mainly account on as follow.1. Constitute one-dimension heat and moisture transfer model of the vertical U type ground heat exchanger in unsaturated soil. The paper firstly introduces the essential concepts and parameters of porosity. And present the model development of heat and moisture transfer in porosity. At last, the paper constitutes the one-dimension physical and mathematical heat and moisture transfer model of GHE.2. The numerical solution of one-dimension heat and moisture transfer model of GHE in unsaturated soil. The solution to the differential equations is limit difference, with front difference to time and center difference to space dots. Then the paper gives the compiled calculation procedure to deal with difference equations sets by Visual Basic 6.0.3. Analyze the effect factors of the one-dimension heat and moisture transfer model of GHE. The effect factors include initial temperature, initial moisture, heat rejection. The paper gives the temperature and moisture distribution of soil under the factors.4. The theoretical analysis model of the GSHP operating performance. The paper establishes the operating analysis model of the GSHP system main parts. Then give the fitted equations about the cooling water temperature of condenser input (of GHE output).5. Validate the heat and moisture transfer model of GHE with the practical operating performance of GSHP system. The paper designs two operating modes to the system, the continuous operating mode and intermittent operating mode. The paper gives the comparative results of experiment and simulation. Although the results are matched, there are somewhere for built model to perfect.