Effect of Wet Soil on Thermal Performance of Air-Fluid Ground Heat Exchanger for Heating

Abstract

The energy crises that emerged after the economic problems in the world increased the interest in alternative energy resources. The effects of global warming, which has a serious threat, will be reduced by the more efficient use of these energy resources. In this study, the thermal effects of wet soil were investigated experimentally using a ground source heat exchanger (GHE), which is an alternative energy resource, in an area on the Esentepe campus of Sakarya University. Researches on this subject are mostly directed to dry soil applications. In this research, the performance of soil in an artificial pool was examined in terms of heat transfer. By means of the artificial pool formed under the ground, it is aimed to increase in heat transfer between the soil and the process fluid. In the experiments which are conducted, air is used as the process fluid. The system has a significant advantage in certain temperature ranges due to the passive heating method, in other words, the process fluid can be circulated under the soil without using a compressor. The purpose of this method is to reduce the cost of heating in the winter season. The temperature difference at GHE inlet and outlet is approximately 9.07 °C in the experiments. The heat transfer rate has been increased by 46.28% compared to dry soil application for the same air velocity speed.

Keywords

• ground base heating,earth air heat exchanger,wet soil

References

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