Numerical predictions of augmented heat transfer of an internal blade tip-wall by hemispherical dimples

Turbulent flow and heat transfer enhancement in rectangular channels with novel cylindrical grooves

“…On the other hand, previous research work [20][21][22][23][24][25] has shown that dimples can provide substantial heat transfer enhancement in confined channels with relatively low pressure loss penalty, compared to that of other types of augmented heat transfer devices such as fins, pins, and rib turbulators. Unlike protruding turbulators, heat transfer of dimpled surfaces is enhanced because vortex structures promote mixing, drawing ''cold'' fluid from outside the thermal boundary layer to make contact with the heated wall, enhancing convective heat transfer.…”

Numerical modeling flow and heat transfer in dimpled cooling channels with secondary hemispherical protrusions

“…1). The values for Nu 0 of fully developed channel flow are obtained by the DittuseBoelter correlation shown in Equation (12).…”

Review of Heat Transfer Augmentation for Cooling of Turbine Blade Tip by Geometrical Modifications to the Surfaces of Blade

“…Also this method resulted in negligible pressure drop as compared to that of a smooth surface of the turbine internal tip. Gongnan Xie and Bengt Sunden [2] simulated the same geometry as given by Bunker. Only here the difference was provision of hemispherical dimples/concave dimples on the internal tip cap instead of arrays in case of Bunker's experiment.…”

“…Gongnan Xie and Bengt Sunden [2] investigated numerically the heat transfer augmentation for the same geometry as that of Bunker. The difference being the provision of hemispherical dimples instead of pin arrays as considered by Bunker.…”