An experimental study on reducing depositing on turbine vanes with transverse trenches

Particles depositing is a severe damage to turbine vanes. The depositing on upper surface for the plate models with film cooling configuration is experimentally studied for the attack angle −5º with a kind of wax, which is melted and atomized to generate particles. Some models are trenched along the row of film cooling holes to study the effects of different trenches with different depths on the depositing. All the trenches could distribute the depositing on the near downstream of the row of film cooling holes more uniformly and the deeper trench could make the depositing on this area more uniform. When the blowing ratio is 0.98, all the trenches could decrease the depositing on the upper surface and the depositing mass decreases with the trench depth increasing. When the blowing ratio is 1.47, all the trenches increase the depositing on the upper surface although the increment is not vary large and the depositing mass increases with the trench depth increasing. However, even if the blowing ratio is 1.47, the trench may reduce the negative effect of the depositing on turbine vanes since it could delay the depositing to the area far from the row of film cooling holes.