Thermal performance augmentation of a solar flat plate collector using the shot peening technique

Abstract

This article deals with the thermal-hydraulic performance of a flat plate solar collector (FPSC) whose copper absorber plate and copper tubing surface are shot-peened to increase the fatigue life, strength, and roughness through a pressurized steel grit shot peening mechanism, to enhance the performance of FPSC. The objective of this experiment is to increase the convective heat transfer coefficient (CHTC) with lowest possible pumping power by augmenting the heat transfer between the absorber plate and the heat transfer fluid. The increase in surface area of the absorber tube and absorber plate made of the copper enables an increment in a specific length for “h” from the absorber area to the heat transfer fluid; this ensures that the surface area exposed to solar irradiance is increased. The experimental results show that the maximum thermal efficiency of the shot peened FPSC was about 54.24% when the flow rate was maintained at 0.02 kg/s. The cost per liter of hot water produced using FPSC whose absorber tube and absorber plate were painted black was about US $0.3.