Study On Coaxial Underground Heat Exchanger And Heat Transfer Model

Energy is one of elements human being needed to survive.It is important strategic material for economy develop and important material base for social living in modern times. In order to avoid the energy crisis and the ecological environment destruction. When the renewable energy and the new energy have not become the primary energy.Two or more resources should be together utilized in the energy framework of divers renewable energy ,because this way can improve use efficiency of every resource by the way of bringing its adwantages into play.Under this condition,ground source heat pump is brought forward as new way or approach of using geothermal.It is necessary and timing.Ground source heat pump technology has already received great attention by the U.S. and European countries for its good energy saving performance and less harm to the environment. At present there is a lack of fundamental study on this area in our country. Therefore, it is important to discuss its component performance and the application issues. For this purpose, experimental study on caoxial style heat exchanger of ground source heat pump is carried out in this paper.Based on a review of related research on ground source heat pump both home and abroad, and applying Jilin University Green Energy Development and Utilization Laboratory. The experimental table accounted to 500 m~2.There are 4 primary parts in this system: outdoor heat interchanger subsystem, heat pump unit subsystem, indoor circulation subsystem and measure and control subsystem. The system has provided the experimental condition for research each aspect of source heat pump system.This article introduced the structure and the characteristic of each kind of underground heat exchanger. Study on coaxial underground heat exchanger. Ground heat exchanger is the research emphases of ground source heat pump system. And many parameters such as temperature, pressure, velocity of flow, flux and heat flux are measured and controlled. These data are used to evaluate entirely ground source heat pump system. It can support in the theory the technology to be used other engineer projects.A heat transfer model of caoxial style tube is established through analyzing its heat transfer process. According to the existing heat interchanger size, the soil temperature and so on, coaxial underground heat exchanger is researched by numerical modeling with FLUENT software. And the conclusions are very useful for the right design of the ground source heat pump system.Influences factors of caoxial style heat exchanger are studied in this paper based on the establishment of the experiment table. According to the boundary conditions and the conditions are known, using finite element analysis software ANSYS solution of the model. The results with the experimental results obtained at the rate of more than 70.5%.By the way of analysis and experimental study, it reveals the performance of caoxial style heat exchanger and its influence factors. Besides, it provides fundamental data to the design and optimization of ground source heat pump system. All the results are applicable to both the theoretical and the practical work.