Operation Performance And Surrounding Soil Temperature Research Of Library Gshp In Donghua University

The system of ground source heat pump is a new energy utilizing technology which uses soil as its cold and heat source, and take advantage of heat pump theory to provide cooling and heating. As is compared by traditional air conditioning, ground source heat pump can be more efficient, more energy saving and more environmental protecting. At present, there are still few project examples about its operating performance and soil temperature monitoring, especially lacking long-term actual operating data. This situation is not coordinated with the high development of the ground source heat pump in our country. Therefore, it is of great practical significance to research ground source heat pump operating performance and its surrounding soil temperature by combing the actual case.This topic set the ground source heat pump system of Shanghai Donghua University library as the background, using experimental tests, theoretical analysis, establishing heat transfer models and numerical simulation during the research. Firstly, a set of automatic control and data collection system is developed by using the METASYS system and King Viewing software, which automatic controls the operation of the ground source heat pump system and real-time records various data. On the basis of that, the operational characteristics of summer and winter of the ground source heat pump will be studied and the emphasis will be put on the research of factors which impact the unit depth of heat and the system cycle performance during the dynamic load. The soil temperature experiment aims at studying the impact on the center and edge of the pipe groups by long-term operation of the ground source heat pump. In order to analyze impact on the soil temperature which near the pipe by system operation, the study established the pipe-soil heat transfer model by GAMBIT in accordance with the experiment. Using FLUENT to simulate soil heat distribution under long-term operation, meanwhile simulate the change of soil temperature by variable load and running time under short-term operation.Through large number of experimental data, this study found the relationship between unit depth of heat, cyclic performance parameters and running time, load, average temperature within the pipe. After one year’s study, we found ratio by winter and summer heat exchanger to the soil heat is1:1.5. The temperature of the center and edge of the pipe groups was not impacted which means high recovery performance.Simulation results consistent with the experimental, we obtained following conclusion: The over more soil temperature around the pipe group showed the law of exponential distribution and was impacted by the unit depth of heat; Magnitude of soil temperature changed various from distance to the borehole. The biggest magnitude of the soil temperature happened at one year running, the temperature only increased1.88℃which had little impact on the ground source heat pump system operation of next year.