The Effect of Construction Methods on Geothermal Exchange Rates of Cast-in-place Energy Piles

Title & Authors
The Effect of Construction Methods on Geothermal Exchange Rates of Cast-in-place Energy Piles
Park, Yong-Boo; Nam, Yu-Jin; Sim, Young-Jong; Sohn, Jeong-Rak;

Abstract
In recent, there are many studies associated with energy piles to save initial construction cost for ground source heat pump system. In this study, to evaluate geothermal exchange rates two types (a connection type and a slinky type) of cast-in-place energy piles (PRD, 4.5m in depth, 1,200 mm in diameter) were constructed for the tests and their efficiencies were compared with numerical analysis results. As a result, starting with operation, geothermal exchange rate gradually decreases due to exchange of lower ground temperature. In the case of connection type, temperature difference is $\small{0.37^{\circ}C}$ in heating mode and $\small{0.34^{\circ}C}$, in cooling mode, respectively. In addition, in case of a connection type, geothermal exchange rate in heating mode is 2,314W/m and in cooling mode, 252.2W/m whose value is 9% higher than in heating mode. In the case of slinky type, the average geothermal exchange rate in heating mode is 168.0W/m, which is about 27% lower than that of connection type.
Keywords
Cast-in-place Energy Pile;Geothermal Exchange Rate;Cooling-Heating Mode Operation;
Language
Korean
Cited by
References
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