Heat transfer in rotating impingement channels with asymmetric curvature target surfaces for different channel orientations and jet hole shapes

This study investigates heat transfer in rotating leading-edge impingement channels with asymmetrically curved target surfaces. Experiments cover jet Reynolds numbers from 5000 to 15,000 and a maximum jet rotation number of 0.39, considering rotating effects, channel orientations, and jet hole shapes on heat transfer. Numerical simulations elucidate flow mechanisms. The results revealed that the asymmetry of the target surface leads to jet preferentially turning towards the trailing side after reaching the stagnation point, resulting in differences in heat transfer between the trailing side and leading side. Furthermore, flow rate redistribution due to rotation significantly enhances heat transfer at lowest and highest radial positions. Coupling flow rate changes and rotating force exhibit similar heat transfer variation trends with rotation at mid-radius position-initial enhancement, attenuation, then further enhancement. Moreover, changes in channel orientations induce Coriolis force components, altering flow rate distribution and jet deflection direction, influencing heat transfer differences among models under rotation. Furthermore, under rotational conditions, the elliptical jet hole model with higher flow rates exhibits significantly weaker rotational enhancement effects in the stagnation region compared to the circular jet hole model.