To optimize the coolant air development space and enhance overall cooling performance,a plug structure positioned within the cooling chamber is proposed for swirl cooling structures used at the leading edges of turbine blades.Based on a simplified swirl cooling structure,the effect and mechanism of the plug structure on the heat transfer coefficient,comprehensive cooling performance,flow distribution and flow structure of the swirl cooling target surface are investigated using the numerical simulation method.The results show that by incorporating the plug structure,within the jet Reynolds number range of 5 000 to 20 000,the average Nusselt number on the swirl cooling structure's target surface increases by 5.9％to 8.3％,the overall cooling effectiveness factor rises by 5.2％to 6.6％,the Nusselt number on the suction side experiences a significant increase of 14.8％to 16.6％,and the maximum difference in flow between adjacent nozzles decreases from 18％to 5％.The plug structure reduces the development space of the upstream jets at the cooling chamber axis,thereby inhibiting the formation of swirl backflow and vortex cores.This reduction minimizes the interference of upstream coolant on fresh jets and strengthens the weakening effect of swirl on the wall boundary layer.Consequently,the plug structure effectively enhances the consistency of the swirl structure and improves the strength and uniformity of the heat transfer coefficient of the target surface.
swirl coolingturbine bladesinternal coolingNusselt numberjetting Reynolds number
NETL
NSTL
万方数据
