Numerical Simulation On Heat Transfer Of GSHP Buried Pipe Based On The Principle Of Energy Storage

Nowadays, resource and environment are one of the hottest problems concerned by the whole world. Ground source heat pump technology has the characteristics of energy conservation and environmental protection. In the process of ground source heat pump system research, the research for ground heat exchanger is one of the important and difficult. Based on the soil temperature field under the premise of not influenced by larger, this paper proposes a exchanger of ground source heat pump on the basis of the principle of regenerative heat exchanger. This heat exchanger with the biggest difference between the conventional ground heat exchanger is composed of two groups of buried pipe run alternately, the disturbance of soil temperature is reduced. Two groups of buried pipe, a set of heat exchange stop running,another set of soil in the back temperature state. For one group of u-shaped exchanger to simulate the process of heat transfer and temperature returning, finding out the heat exchanger alternately running time with two groups of buried tube, and making the reversing cycle diagram. Mainly on the three-dimensional unsteady vertical U shape buried pipe heat transfer model was simulated with CFD software. The mathematical model, geometric model, mesh generation, single valued condition and physical property parameters are given. The main research contents are as follows:(1) The first simulation system of long run impacts on the soil temperature field. According to the contrast can know, based on heat storage principle of the ground source heat pump buried heat exchanger have less effect on the soil temperature field.(2) It will detail analysis of heat transfer process, and determine a reasonable standard of exchange period. It is resolved by means of monitoring the exit water temperature of import and export water temperature difference, when the water temperature difference satisfy the premise of the theoretical calculation to determine the exchange period, and the exchange period is obtained.(3) Because of the different parameters of the soil in each region, the thermal conductivity of the backfill is changed, the greater the heat conduction coefficient is, and the longer the exchange period is.(4) In comparison with the simulation of refrigeration condition, the change of the thermal conductivity of the back fill is increased, and the change of the exchange period is also increasing.(5) In backfill soil coefficient of thermal conductivity under the same conditions, working condition of refrigeration and heating condition of reversing cycle difference is very small, so you can use the same exchange period. Here the heat exchanger range has little effect on soil temperature, provide the basis for reducing the parallel buried tube spacing.In this paper, the research methods and research results, to improve the stability of the whole heat pump work and decrease soil temperature disturbance to provide certain reference.