Shashi Shukla, H. S. Sahu
A 3-dimensional CFD analysis has been carried out of solar air heater to study heat transfer and fluid flow behavior in a rectangular duct of a solar air heater with one roughened wall having combination of circular and square transverse wire rib roughness. The effect of Reynolds number, roughness height, roughness pitch, relative roughness pitch and relative roughness height on the heat transfer coefficient and friction factor have been studied. In order to validate the present numerical model, results have been compared with available experimental results under similar flow conditions. CFD Investigation has been carried out in medium Reynolds number flow. CFD analysis has been carried out to study heat transfer and fluid flow behavior in a rectangular duct of a solar air heater with one roughened wall having W shaped wire rib roughness. a numerical analysis of convective heat transfer enhancement in solar air heaters with artificially roughened absorber is presented in this project. CFD numerical simulations were carried out to analyze the flow and heat transfer in the air duct of a solar air heater provided with transverse ribs (W shaped).W-shaped roughness gives better heat transfer rate as compare to the V rib roughness because of more secondary flow development in W rib under similar operating conditions. the maximum value of Nusselt number for W-shaped roughness is obtained with the relative roughness pitch (P/e) of 10 beyond that it starts decreasing i.e. at P/e = 12. The maximum increment in Nusselt number for W-shaped roughness is found to be 2.34 times as compare to the smooth surface at Re = 14000.The maximum increment in Nusselt number is found to be 1.15 times as compare to the V rib roughness at Re = 14000.
CFD Analysis, Absorber plate, Enhancement Factor, Reynolds’s No., Nusselt No