Heat Transfer Enhancement by Detached-Ribs on a Surface Subjected to Jet Impingement

The jet Reynolds number is varied from 15,000 30,000. It is found that square grooves give higher heat transfer than the triangular ribs. Ekkad and Kontrovitz investigated the effect of dimples on the local heat transfer along with turbulent impinging jet. It was observed that heat transfer in a hemispherical cavity largely depends on cavity and nozzle diameters ratio. It is found that contrary to a smooth surface, there is a continuous increase in Nusselt number from a stagnation point. Turbulent impinging jets with surface enlargement are a promising technique for heat transfer enhancement. It is found from the work of numerous researchers, available in open literature, that for the case of impinging jet, the shear stress transport (SST) model predicts flow field and heat transfer results more accurately than other eddy viscosity models. The secondary peak in Nusselt number distributions is not identifiable, as the flow in this zone is highly complex and governed by non-equilibrium effects through high acceleration and streamline curvature.