Thermal Response Experiment And Numerical Simulation Of Buried Pipe Heat Exchanger

Ground-source heat pump technology is an effective way to develop and uselow-temperature geothermal resources, in Europe, the United States, Japan and otherdeveloped countries. It has long been widely promoted, and has been more and morewidely used in domestic fields in recent years. When we design the heat exchange ofground-source heat pump systems or underground power storage, the accuracy ofthermal properties parameters of sock and soil is very important. To solve thisproblem, firstly, this thesis introduces the testing method of thermal physicalproperties of sock and soil and their respective characteristics, the thesis also makesa detailed account of the existing analytic method heat transfer model and numericalmethod heat transfer model, and focuses on the advantages and working principlesof thermal response testing.The thesis applies FLUENT to model soil temperature field simulation in theprocess of testing, analysis of the temperature distribution on the horizontal directionand vertical direction. Analyzed the heat transfer situation between the undergroundheat exchanger and the soil around, in the condition of different backfill materialcoefficient of thermal conductivity, pipe diameter, geotechnical coefficient ofthermal conductivity. This analysis method is also applicable to simulatetemperature changes in long-term operating mode of heat pump system.In this paper, multiple measuring points in Handan-Xingtai areas weremeasured with the use of homemade thermal response tester. Start with Longquantemple toll station as an example, we introduce the process of the composition andworking principle of test equipment and construction process. Then discuss themethods to determine the time of thermal response test and the initial temperature ofthe earth. Finally, combining the line heat source model and the least square methodto calculating and analyzing the measured data of the Longquan temple toll station,got the rock and soil coefficient of thermal conductivity in Longquan temple tollstation. In the final, analyzed the cause of error factors in the experiment.On the basis of the specific example we have tested some different points inHandan-Xingtai area, the site of the test and calculation results are analyzed.Analysis process mainly includes the distribution of geological structures, groundwater, the initial ground temperature, etc., then draws a certain conclusion, analyzed the Handan-Xingtai areas regularity of rock and soil coefficient of thermalconductivity.