| Title |
Thermal Performance Variations of Glass Evacuated Tube Solar Collectors Depending on the Absorber Shape and the Incidence Angle of Solar Ray |
| Keywords |
Thermal performance ; 열성능 ; Absorber tube shape ; 흡수관 형상 ; Incidence angle ; 입사각 ; Beam and diffuse radiation ; 직달 및 산란 일사 |
| Abstract |
The thermal performances of glass evacuated tube solar collectors are numerically investigated. Four different shapes of solar collectors are considered and the performances of these solar collectors are numerically investigated. Dealing with only collecting tube, the effects of not only the shape of the absorber tube but also the incidence angle of solar irradiation on the thermal performance of the collector are studied because the energy obtained by the absorber can be varied according to the incidence angle of solar radiation. However, the solar irradiation consists of the beam radiation as well as the diffuse radiation. Also, in actual system, the interference of solar irradiation and heat transfer interaction between the tubes should be considered. Therefore, this study considered these effects is carried out experimentally and numerically. The accuracy of the numerical model is verified by experiments. The result shows that the thermal performance of the absorber used a plate fin and U-tube is about 25% better than those of the other models. |