Abstract
Heat transfer augmentation features for the improvement of heat transfer from the absorber-plate of a solar air heater to the working fluid are mostly fins however these features also increase pressure drop in the flow channel. The exergy optimization philosophy is adopted in the fin sizing for this air heating application; this optimization philosophy ensures that the maximum quantity of heat is transferred by the fins while generating the least entropy in the system thus conserving exergy. Results indicate that the higher the fin efficiency, the higher the heat conversion and delivery potential. Given an optimum fin length (efficiency) and superior coating absorptive vigour, useful energy losses in the heater can be minimized. Some important observations relevant in design are made.
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Nwosu, N.P. Employing exergy-optimized pin fins in the design of an absorber in a solar air heather. Appl. Sol. Energy 45, 248–253 (2009). https://doi.org/10.3103/S0003701X09040069
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DOI: https://doi.org/10.3103/S0003701X09040069