Numerical Analysis for the Performance of a SAH Having Different Corrugated Shapes of Absorber Plates

Abstract

Solar energy is the cleanest and most viable solution in energy generation process and contributes to the achievement of net-zero carbon emissions. Solar air heater (SAH) is a well-established technology to convert solar energy directly into thermal energy and used for low temperature applications. However, the performance is poor due to low convective heat transfer between absorber plate and air circulating inside the duct. The convective heat transfer can be improved by providing artificial roughness to the underside of the absorber plate. Different types and shapes of roughness geometries have been employed and investigated by various researchers. However, there is still scope to investigate the efficient roughness geometry. Keeping in this view, a V-shape corrugated and sine-wave corrugated geometry have been investigated in the present study. A 3D CFD analysis on the thermal performance of SAH having different parameters (wavelength, λ and amplitude of sine-wave, a) of corrugated shapes is investigated for different Reynolds number (Re). Based on fluid flow analysis, it is found that roughness geometry having sine-wave corrugation results in higher Nusselt number (Nu) and lower friction factor (f) in comparison to V-shape corrugated geometry.