Study On Performance Of Ground Source Heat Pump In Chengdu

Ground Source Heat Pump (GSHP) is applied to many areas because of its high efficiency, steady performance, energy saving, and environment friendly, the research on it have became one of the most hot problem in clean energy area.The heat transfer of ground heat exchanger is the vital of GSHP. The research about ground heat exchanger mainly focus on investigating heat transfer mechanism and performance according to capability experiment and numerical simulation, effect factors of heat transfer ability. All of above don't connect with dynamic building load, which can't gain its practical performance.A new model combing numerical simulation and analytical solution is proposed for U tube ground heat exchanger with varied heat flux boundary. The calculation area is divided into two parts by the boundary of the borehole wall. For the area in the borehole and the surrounding soil area, the calculation method is steady analytical solution and unsteady numerical simulation respectively. The two parts are coupled by the temperature of the borehole.Complex GSHP model coupled with ground heat pump is also established. It is believed that the performance of GSHP only relate outlet circle water temperature in underground heat exchanger when circular medium flux of condenser or evaporator keep steadily. In order to realize the simulation to the whole system, outlet circle water temperature in underground heat exchanger is used to associate with performance of GSHP and underground heat exchanger, their relationship can be gained by analyzing thermodynamic power cycle on the basis of performance data provided by GSHP manufacture. Then, Compaq Visual Fortran 6.5 is adopted to program in order to realize simulation to the hole system.According to above achievements, effect of intermittent operation on the heat transfer performance and the restoration of soil of a vertical U buried pipe heat exchanger is investigated after discussing the intermittent operation models in classic buildings. Then based on a demonstration project in Chengdu, a yearly dynamic analysis on Ground Source Heat Pump systems, which predict heat transfer performance and temperature response of soil.At last, Ground Source Heat Pump computation soft is designed. It contains functions as follow:analysis of ground heat exchanger heat transfer capability effect factor, ground heat exchanger, analysis of dynamic performance of Ground Source Heat Pump system. All of the research enriches the theories of Ground Source Heat Pump heat transfer.