Efficient design of a wavy channel embedded with porous media for solar air heating

In this experimental thermal performance investigation, we present a solar air heater design exhibiting a wavy channel embedded with porous media to illustrate the enhanced fluid mixing and heat transfer area, and consequently high thermal performance. In this design, two wavy plates form the air flow channel and wiremesh as a porous media of high porosity is inserted in the wavy channel to maintain the channel porosity. Results of the investigation revealed promising scope for thermal performance enhancement. Thermal and thermohydraulic efficiency of 38-93% and 38-89%, respectively, is obtained for the investigated range of Reynolds number (2000 <= Re <= 11000) and channel porosity (97% <= phi <= 100%). Moreover, the obtained result of thermal and thermohydraulic efficiency for 97% channel porosity is 27% and 24%, respectively, high compared to 100% channel porosity. As a part of this work, we also presented the developed correlations for Nusselt number and friction factor to predict the thermal performance of wavy absorber plate embedded with porous media and the effect of Darcy number on the thermal performance.