Numerical investigation on location of protrusions and dimples during slot jet impingement on a concave surface using hybrid ANN–GA

Abstract

AbstractNumerical simulations using ANSYS Fluent 17.2 are explored for a detailed discussion on jet impingement over a compound dimpled and protrusioned concave surface. Previous researchers have proved that both dimples and protrusions help in heat transfer augmentation. However, the combined effect of dimple and protrusion over a concave surface is still not studied, which may show a significant improvement in heat transfer. Therefore, the present study is devoted to the alternate location of dimple and protrusion over a concave surface for enhancement in impingement heat transfer. Simulations are performed for several arrangements of dimples and protrusions over a concave surface. It is noticed that a particular arrangement of dimples and protrusions leads to an increase in heat transfer compared with a fully protruded or fully dimpled concave surface. Furthermore, it is also noticed that protrusions/dimples at the stagnation region degrade overall impingement heat transfer. The wall shear stress profile is found to be similar to its corresponding local Nusselt number profile. Lastly, the optimal location of dimples and protrusions is predicted using an artificial neural network and a specially formulated discrete version of genetic algorithm.