CFD Analysis of Single Flow Solar Air Heater with Double ARC Roughness

Artificial roughness is used for enhancement of thermal performance of solar air heaters in the form of repeated ribs has been proposed as a convenient method. This thesis presents the CFD investigation of heat transfer and friction factor characteristics of a rectangular duct roughened with repeated Double arc, on one broad wall arranged at an inclination with respect to the flow direction. The duct has a width to height ratio (W/H) of 8, relative roughness pitch (P/e) of 10, relative roughness height (e/Dh) of 0.044, and arc angle of 15?, 30? and 45?. The comparision of heat transfer and friction characteristics of roughened duct and smooth duct under similar flow condition is simulated in this. The effect of change in angle of attack in flow having Reynolds numbers from 2000 to 16,000. The maximum enhancement in Nusselt number and friction factor is observed to be 1.69 and 1.79 times of that of the smooth duct, respectively. The thermo-hydraulic performance parameter is found to be the maximum for the arc angle of 30?.