The effect of psychrometry on the performance of a solar collector.

The investigation of a solar collector is based on the thermal behaviour of a carrier fluid and the degradation of energy across a flat plate collector. The exergy analysis of a thermal system includes the change in the exergy function of a carrier fluid while transferring solar radiation across an air gap. The cell cast acrylic glass was used to transmit the incident solar radiation to the absorber plate, and to safeguard the absorber plate from the outside environment. With the help of the steady flow energy equation, the enthalpy of the carrier fluid (moist air) was calculated. The specific humidity of the incoming air was calculated at an average dry bulb temperature of 299.4 K. The stagnation temperature at a limiting condition was also estimated to find out the maximum permissible limit for a given thermal design. The mass flow rate of air was assumed to be 5.2 g-s(-1). The efficiency of the solar collector was found to vary from 40 to 42%, whereas the thermal energy available for drying was 15-59% of the exergy of the carrier fluid. The net entropy generation rate due to the collector plate was calculated to be 0.12 W-K(-1).