A numerical investigation is carried out to study flow and heat transfer (HT) performance of impingement/swirl cooling structures in the turbine leading edge (LE) adopting shear stress transport (SST) k-ω turbulent model. The influence of Re, the ratio of impingement cooling (IC) hole offset distance to IC hole diameter (e/d) and coolant outflow structure are analyzed. Results show that for a model without film holes, the first IC jet forms a large vortex because of the limitation imposed by one side wall of the LE. The remaining four IC holes all form a small entrainment vortex near the impact target surface (TS) due to the outlet diversion effect. When Re = 20 000 and e/d = 0, the impingement jet is not uniformly diffused to the left and right sides but flows more along the inclined plane. Both the turbulent pulsation and turbulent kinetic energy (TKE) in the wall region impacted by the jet increase as Re increases, and the region generates small entrainment vortices. When Re = 20 000, regardless of e/d, the region with a high level of TKE includes a region of vortex generation, a region of vortex collision in opposite directions and the wall where the jets make impact.
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