Heat and fluid flow enhancement of the structure of a solar air heater with optimized distance between rib and groove

Abstract

A popular and common method to enhance the heat transfer in a flow passage is to artificially roughen the surfaces with ribs, grooves or combination of ribs and grooves (rib-grooved surface). In this paper, heat transfer enhancement of optimized ribgrooved surfaces in channels is multi objectively optimized applying the NSGA II algorithm. The distance between rib and groove was set from 0 to 3w. The optimized distance between rib and groove was d=2.2w which computed by considering maximum heat transfer and minimum friction factor, simultaneously. The effects of Reynolds number of 5000 to 30000 are so investigated. when the velocity of flow increases the Nusselt number and pressure drop increase .When the distance between rib and groove increases the Nusselt number increased while the friction factor decreases in optimization with NSGAІІ algorithm point=2.2w was the best.