. As Ground Supply Heat Pump Ground of several aspects influencing heat transfer is difficult to style, standard data, and some of the improper selection of parameters will trigger unacceptable project cost, restricted the technology, so till the last century till the late 80’s in the business, civil Creating Of Air conditioning Method used. In current years, a massive quantity of reports reflecting the function carried out abroad, and the outcomes accomplished  .
Since of its environmental protection and energy saving characteristics, ground source heat pump method in China is becoming far more and far more attention, specifically in current years, the nation started to have ground source heat pump system in fact functions. Consequently, the ground supply heat pump design details, and match with the traditional building method is small data on ground supply heat pump engineering case research and lessons discovered in international study on ground supply heat pump is an critical aspect.
In ground supply heat pump systems, geothermal heat supply of the analysis has been to Heat Pump The troubles, but also is the core of the technologies and application of foundation. Current geothermal heat exchanger design and style methods are based on the United States and Europe on geothermal heat exchanger pilot study. Domestic connected research focuses on ground supply heat pump geothermal heat exchangers are placed on the pilot studies, had been also offered the relevant experimental final results. The absence of a heat exchanger in the complex mechanism of heat transfer in soil-depth analysis, producing conclusions apply only to a particular experimental technique, theory is poor, supply standard information and less, therefore creating it hard to guide the actual style . As a result, it is one particular of the study is to create closer to the actual predicament of the ground heat exchanger heat transfer model.
Is properly recognized, ground supply heat pump technique consists of two parts figure out the major traits: 1st, the length of geothermal heat exchangers and configuration, and second, matched heat pump efficiency. Therefore, the ground heat exchanger configurations have been defined situations, the performance of ground source heat pump method functions how is most concerned about. Consequently, the content of this investigation is to develop another geothermal heat pump heat exchanger and a dynamic model and by experimental verification of the model.
1. Evaluation of the geothermal heat exchanger model
According to the various layout, closed-loop geothermal heat exchangers can be classified into horizontal and vertical heat exchanger buried two categories. Vertical Geothermal heat exchanger is set in a number of vertical borehole ground heat exchanger buried in the ground, generally in the type of U-tube ground. U-tube geothermal heat exchanger is a U-tube borehole arrangement, together with backfill material, and the surrounding soil form a complete. A borehole can set one particular group of U-tube, you can set the two U-tube. Vertical Buried small footprint, heat transfer efficiency, the project has been widely employed, this post in order to project the most broadly utilized example a single U-tube. As the geothermal heat exchanger heat transfer procedure involved in the complicated nature of geothermal heat exchanger heat transfer model is still the foreign closed-loop ground source heat pump program concentrate. The geothermal heat exchanger heat transfer, so far no universally accepted model and specification. Internationally obtainable heat transfer model can be largely divided into two categories. The first category is based on the notion of thermal analytical models, the second approach to discrete numerical model based on the numerical remedy. The 1st model utilizes a line heat supply model or Kelvin infinite cylinder model  . The idea of semi-empirical approaches such straightforward and simple for engineers to accept, and consequently the application of a specific project. The drawback is that the calculation of the thermal entry done a lot of simplifying assumptions  , Model is also basic and restricted to the aspects considered, in distinct, is hard to contemplate the cold, heat load with time, hot and cold throughout the year of conversion and load imbalance far more complex aspects. The second class strategy to discrete numerical heat transfer model primarily based on, can be deemed close to reality, utilizing the finite element or finite difference strategy for ground temperature response and heat transfer analysis. However, due to geothermal heat exchanger spatial extent of the dilemma requires a massive, complex geometric configuration, and load adjustments more than time, the time span of much more than a decade, so if this method by utilizing 3-dimensional non-steady-state problem solving sensible engineering difficulties will price a lot of personal computer time, the calculation of the current projects below the direct dilemma solving is practically impossible. This strategy is presently only suitable for certain research perform carried out beneath simplified situations in the parameter evaluation, but not for undertaking large-scale multi-borehole ground heat exchanger heat transfer simulation, considerably less appropriate for engineering design and optimization.
2. Vertical single U-tube ground heat exchanger model