Coating Growth on Turbine Blade in Polydisperse Particles/Hot Gas Flow

Deposition of particles onto a turbine blade in cascade inclined at some angle to the flow at infinity is considered. The submicron particles are thermophoretically deposited onto the blade surface, whereas supermicron particles strike it inertially. A coating at the foil surface is accumulated due to the thermophoretical deposition and polished as a result of supermicron particle strikes. The competition of these two processes does not lead (generally as regards the flow around the foil) to the emergence of steady-state continuous coating at the blade surface. However, some slowly growing coating islands may be obtained and used to protect the blade. The effects of various flow and blade parameters on the coating growth are studied.