Impact of hybrid roughness geometry on heat transfer augmentation in solar air heater: A review
Shuchi Chaurasia, Varun Goel, Ajoy Debbarma
Abstract
An effective method to increase the heat transfer rate of fluid flowing in a solar air heater duct (SAHD) is to apply artificial roughness geometry over the absorber plate. The heat transmission rate is determined by the type of roughness geometry applied and its proposed arrangement in the duct. The present review article aims to discuss the combination of two roughness geometries in the range of studied parameters and to obtain the optimum values for performance enhancement. The flow pattern of the combination of two roughness geometry has been studied. Hybrid roughness is categorized mainly into four basic sections i.e., rib roughness with staggered elements, a combination of two different rib geometries, rib roughness combined with a vortex generator and different types of rib arranged with grooves. This study focuses on analyzing the parameters responsible for the maximum heat transfer and thermal performance. An attempt has been made to highlight the numerous earlier research work done by the various researchers by considering single roughness geometries implemented over the absorber plate for the augmentation of heat transfer.