Flat plate air-heater improvements

Several design improvements in flat-plate solar air heaters are examined, with the objective of increasing the rate of heat transfer from the absorber to the flowing air. The steady-state energy balance equation on the absorber plate is employed to determine those parameters which may aid in raising the heat transfer rate. Collector designs involving dimpled absorbers, finned absorbers or the interruption of the absorber surface are proposed as candidates for comparison with a standard collector having non-selective coatings, two glazings and conventional tube-in-sheet or plane duct flow passages.