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.