Abstract:It is good for the consumer to have solar cookers of various varieties in terms of geometrical designs, performance and price but it is a ch allenge to develop a u niform test standard for evaluating the thermal performance of the cookers irrespective of their geometrical construction. Due to the lack of uniform test protocol, consumer cannot compare the quantitative performance of the cookers of different configuration and become confused. For this end, we plotted graphs between exergy output and temperature difference, for solar cookers of different designs and it resembled a parabolic curve for each design. The peak exergy (vertex of the parabola), can be accepted as a measure of devices' fuel ratings. The ratio of the peak exergy gained to the exergy lost at that instant of time can be considered as the quality factor of the solar cooker. Besides, the exergy lost is found to vary linearly with temperature difference irrespective of the topology of the device and the slope of the straight line obtained through curve fitting represents the heat loss coefficient of the cooker. The proposed parameters can lead to development of unified test protocol for solar cookers of diversified designs.

No abstract

No abstract