Numerical Investigations on Turbulent Transport Phenomena over a Moving Surface Due to Impinging Annular Jets

In the present paper, turbulent flow field and heat transfer over a moving surface under an array of impinging annular jets have been numerically studied. The flow field was resolved using the transition SST model with highly refined mesh. The values of non-dimensional surface velocity were considered from zero (stationary surface) to two times of the inlet jet velocity. The study depicts that both the flow field under the jet and the corresponding thermal performance are strongly affected by the surface movement. Variations in the flow profiles and skin friction distribution at different surface velocities are documented. The initial symmetric distribution of heat transfer pattern for a stationary jet is broken as the surface starts moving, leading to a reduction in average heat transfer. However, after a certain velocity of the surface, the total heat transfer again starts increasing with a more uniform and enhanced heat transfer for high surface velocity cases. The level of near-wall turbulent kinetic energy is also found to initially reduce with imposing surface motion which, starts increasing at higher surface velocity. It is observed that the heat transfer from impinging surface at different velocity is closely linked with the strength of turbulent field.