...Pranjal Prasad Newar; Biplab Das A roughened solar air heater is developed numerically and experimentally with a novel roughness in the absorber. The roughness incorporated is a combination of rectangular and semi-circular ribs. The analysis is done to improve the thermal characteristics...

... is kept constant. The channel design that gives the best performance was further investigated by incorporating a sinusoidal wavy absorber having variable wavy roughness parameters. The flow and heat transfer characteristics have been evaluated in terms of friction factor (f) and Nusselt number per unit...

... wall of the domain was considered as a no-slip wall without roughness. The top wall was specified as zero-shear stress (or slip wall) to prevent boundary layer formation. Note that this simplification has little influence on the simulations since the boundary layer formed on the top wall...