Impingement heat transfer enhancement in crossflow by a skewed twisted rib pair for simplified leading edge structure

Impingement cooling is a widely used cooling technology with extremely high local heat flux dissipation, but its heat transfer is often destroyed by upstream crossflow. To improve the impingement heat transfer under crossflow condition, a skewed-twisted rib pair is proposed for simplified leading edge structure. The flow and heat transfer characteristics of Baseline and STRP cases are compared when the crossflow ratio varies from 0.2 to 0.4. According to the results, in both Baseline and STRP cases, increased crossflow ratio results in a decrease in impingement heat transfer, and it also leads to the peak value location of Nusselt number shift further downstream. Besides, with the increase of crossflow ratio, the total pressure-drop of jet decreases, but that of crossflow increases. Under the same crossflow ratio, the arrangement of STRP intensifies the turbulence level and induces an additional vortex pair whose centerline direction is same as jet, so the impingement heat transfer performance is improved effectively. Moreover, the effect of skewed-twisted rib pair height is considered, and it is found that the increased height makes the heat transfer enhancement effect get obvious, but it also leads to an increase in total pressure-drops of both jet and crossflow.