沟槽平板颗粒沉积特性和气膜冷却性能

Particle deposition characteristics and film cooling performance of flat plate with trench

通过将平板上的气膜冷却孔嵌入横向沟槽中,探究沟槽深度对平板颗粒沉积分布和气膜冷却性能的影响。结果表明:沟槽结构的存在改善了平板表面的颗粒沉积情况和气膜冷却性能,并将一定颗粒阻隔在沟槽内部。在同一吹风比下,沟槽深度的增加使得整体的颗粒碰撞效率增大。在吹风比较小时,3种沟槽深度的结构减小了平板颗粒的沉积和捕获,并改善了冷却孔下游气膜冷却效率。但在大吹风比下,不同沟槽深度改善颗粒沉积分布和气膜冷却效率方面各有差异。对比不同沟槽深度结构在各个工况下的性能,沟槽深度为0.8倍孔径的结构在改善颗粒沉积分布的同时也能兼顾提升气膜冷却孔下游的气膜冷却效率。

The effects of different trench depths on the particle deposition distribution and film cooling performance of the flat plate were explored by embedding the cooling holes into the trench. The result showed that the existence of the trench structure improved the particle deposition and film cooling performance on the flat plate, and effectively blocked certain particles inside the trench. Under the same blowing ratio, the increase of the trench depth made the overall particle impact efficiency increase. When the blowing ration was relatively small, the three trench depth structures all reduced the particles deposition and capture on the flat plate, and improved the downstream film cooling efficiency of the cooling holes. However, under the large blowing ratio, different trench depths had different performances on particle deposition distribution and film cooling efficiency. Comparing the performance of different trench depth structures under various working conditions, the structure with a trench depth of 0.8 times film cooling hole diameter improved the particle deposition distribution and can also promote the downstream film cooling efficiency of the cooling holes.