Thermal Performance Testing of a Flat Plate Solar Air Heater Using Optical Measurement Technique

Abstract

Experimental test set up at laboratory scale has been developed for thermal performance testing of flat plate solar air heater with simulated solar radiation intensity; 600W/m 2 . A test cell of size 1m x 0.5m x 0.1m was fabricated. Three designs namely (i) plane absorber (ii) transverse V- porous ribs and (iii) inclined V-porous ribs of absorber are tested. All the experiments are conducted with artificial solar radiation and in natural convection. Performances of these three designs have been compared on the basis of overall thermal efficiency and thermal gradient along normal to the base. Thermal gradient has been determined by laser beam deviation method. PT-100 temperature sensors have also been used to validate the optical results of thermal gradient. The overall thermal efficiencies of these designs have been found as 14.91%, 17.24% and 20.04% respectively. It has also been seen that thermal gradient tends to reduce with increase in efficiency.