# 태양열 집열관 과열방지를 위한 지중열교환기 연구

• Hwang, Hyun-Chang (School of Mechanical Engineering, Chungbuk National University) ;
• Chi, Ri-Guang (School of Mechanical Engineering, Chungbuk National University) ;
• Lee, Kye-Bock (School of Mechanical Engineering, Chungbuk National University) ;
• Rhi, Seok-Ho (School of Mechanical Engineering, Chungbuk National University)
• 황현창 (충북대학교 기계공학부) ;
• ;
• 이계복 (충북대학교 기계공학부) ;
• 이석호 (충북대학교 기계공학부)
• Accepted : 2016.07.07
• Published : 2016.07.31

#### Abstract

The heating load using solar hot water is lower in summer than in the other seasons. This decreased heating load leads to the overheating solar collectors and related components. To prevent overheating of the solar collectors, air cooling and shading shields were used. On the other hand, it requires additional mechanical components, and reduces the system reliability. The geothermal heat dump system to release the high temperature heat (over $150^{\circ}C$) transferred from the heat pipe solar collectors was investigated in the present study. Research on the heat dump to cool the solar collector is rare. Therefore, the present study was carried out to collect possible data of a geothermal heat dump to cool the solar collector. A helical type geothermal heat exchanger was buried at a 1.2m depth. Experimentally and numerically, the geothermal heat dump was investigated in terms of the effects of parameters, such as the quantity of solar radiation, aperture area of the collector and the mass flow rate. A pipe length of 50m on the geothermal heat exchanger was suitable with a 0.33 kg/s flow rate. The water reservoir was a possible co-operation solution linked to the geothermal heat exchanger.

#### Acknowledgement

Supported by : 충북대학교

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