| Title |
Measurement of Ground Thermal Conductivity and Characteristics of Thermal Diffusion by the Ground Heat Exchanger |
| Authors |
정영만(Youngman Jeong) ; 구경민(Kyungmin Koo) ; 황유진(Yujin Hwang) ; 장세용(Seyong Jang) ; 이영호(Yeongho Lee) ; 이동혁(Donghyuk Lee) ; 이재근(Jaekeun Lee) |
| Keywords |
열전도도 ; 열확산 ; 지중열교환기 ; 보어홀 Thermal conductivity ; Thermal diffusion ; Ground heat exchanger ; Borehole |
| Abstract |
This paper presents the measurement of ground thermal conductivity and the characteristics of ground thermal diffusion by a ground heat exchanger(GHE). A borehole is installed to a depth of 175m with a diameter of 150mm. To analyze the thermal diffusion property of the GHE, thermocouples are installed under the ground near the GHE. The outdoor temperature, the ground temperature, and the water temperature of the GHE are monitored for evaluating the characteristics of ground thermal diffusion. The ground thermal conductivity is evaluated by the in-situ thermal response tester and the line source model. It is found to be 3.08W/m℃ in this study. The ground temperature is greatly dependent on the outdoor temperature from the ground surface to 2.5m in depth and is stable below 10m in depth. The surface temperature of the GHE varies as a function of the temperature of circulating water. But the ground temperature at 1.5m far from the GHE is not changed in accordance with the temperature of circulating water. |