Performance enhancement of solar air heater by attaching artificial rib roughness on the absorber Plate

Abstract

Despite the limitations of conventional energy sources, the current energy scenario is still biased towards the use of these resources. Solar energy is regarded as a vital component of sustainable energy development due to its environmental friendliness and abundant resources. Solar air heaters (SAHs) are devices that convert solar energy into thermal energy by using air as a working fluid. SAHs are used in various applications due to their low cost and operation. The low thermal efficiency of SAHs can also limit their effectiveness due to the low temperature rise caused by the air. Due to the high thermal losses from the SAH, it is important to improve its performance in turbulent flow. Various efforts have been made to improve the heat transfer rate through the use of various components such as ribs, baffles, and fins in SAHs. This paper presents a detailed review on the thermal performance of a SAH with a ribbed absorbing plate. The use of artificial roughness has been found to improve the thermal performance of the SAH. The various configurations of the ribs have been presented in order to provide an optimized SAH design. This article aims to describe and conclude the studies on the influence of ribs on the SAH duct's pressure drop and heat transfer rate. It also explores the effects of varying the surface roughness on the performance of SAHs.