A Study of Solar Reflector Efficiency of Parabolic Dual Trough

Abstract

Problem statement: The receiver of parabolic dual trough had been designed and built in order to increase efficiency of solar radiation accumulation by using iron-aluminum sheet as an intermediate in receiving heat and it is the study into how to benefit from solar radiation energy. This research proposed the principle of changing solar radiation to be heating energy by using aluminum sheet made into dual parabolic curve tilted with iron-aluminum sheet which was receiver of radiation reflection. Approach: This dual parabolic curve could be adjusted so that heat obtained from the solar radiation accumulation, which was the focus, could spread around iron-aluminum sheet. In testing of heating by solar energy, the unit would be tilted at 16° to the North-South in order to receive solar radiation and the unit was arranged horizontally. The test was classified into 4 conditions including (1) laying the unit horizontally and un-drive the motor, iron-aluminum sheet would be put in place unmoved in vertical line; (2) laying the unit horizontally and drive motor so that iron-aluminum sheet could be moved upwards and downwards along the vertical line; (3) laying the unit to be tilted at 16° with plane level and un-drive motor and (4) laying the unit to be tilted at 16° with the plane level and drive motor so that iron-aluminum sheet could be moved upwards and downwards along the vertical line. Results: It was found from the test of temperature of iron-aluminum sheet that on the first condition, the highest temperature of iron sheet was 75.2°C and the highest temperature of aluminum was 84.7 °C; on the second condition, the highest temperature of iron sheet was 90.6°C and the highest temperature of aluminum was 97.2°C; on the third condition, the highest temperature of iron sheet was 87.4°C and the highest temperature of aluminum was 93.4°C; on the fourth condition, the highest temperature of iron sheet was 94.5°C and the highest temperature of aluminum was 89.4°C. Therefore, the test of laying the unit to be tilted at 16° with the plane level and driving motor leaded to the high temperature since the perpendicular of light and the spreading of sunlight from dual parabolic curve could cover all area. Conclusion: These results indicate dual parabolic curve could be increased efficiency of solar radiation accumulation by using iron-aluminum sheet as an intermediate in receiving heat.