Numerical Simulation Of The Factors Influencing Performance Of High Temperature Thermal Energy Storage In Underground Heat Exchangers

Nowadays, with the development of modern social needs, energy conservation & emission reduction and the promotion of green urban development have become a central theme of building a harmonious society. Seasonal heat storage of solar thermal energy as a new heating technology has great potential. Among of that, maturity of the underground heat exchanger application technology makes the buried pipe with seasonal solar heat storage as the preferred way of underground thermal energy storage.In this paper, numerical simulation techniques has been used to study the heat transfer process in high-temperature thermal storage of various factors on the impact of underground heat exchanger, using a three dimensional model to simulate the situation. The obtained results have a comparison with engineering data to verify the correctness of the model.Solar energy stored in the soil are affected with the heat of the soil, This dissertation simulated three types of soil with different temperature distribution, outlet temperature and heat exchange under different rate of water content. There is the result that heat transfer device has different heat transfer performance under different circumstances change and obtain the evaluation of soil parameters for long-term thermal storage. Underground heat exchanger by changing the import of different temperature, the flow rate, pipe depth and spacing of the size of the wells to analysis the factors that affect heat exchanger performance. U-tube ground by comparing the single and double U-tube ground simulation results, obtained the heat transfer performance of double U higher 20% when compared with the single U. Finally, a simulation on continuous soil heat storage verifies the feasibility of soil temperature thermal storage.