THERMAL PERFORMANCE EVALUATION OF A PROPOSED POINT-FOCUS SOLAR COLLECTOR FOR LOW POWER APPLICATIONS

In this study, thermal performance of a proposed point-focus solar collector for low power applications was estimated under different operating variables. For this purpose, theoretical analysis was employed with varying relevant parameters, using a set of thermodynamics and energy equations, i.e., ambient temperature, beam solar insolation, wind speed, wind incidence angle and wall temperature of the absorber. The results show decreasing trend of the wind incidence angle along with increasing the convective heat loss coefficient as the highest related values obtained under head-on wind flow, but the wall temperature of the absorber exerts negligible influence. The maximum thermal efficiency of 79.68% was obtained in August with the side-on wind flow of 4.9 m/s and an ambient temperature of 29.2°C when the absorber wall temperature has a minimum value of 150°C.