The Influence of Substrate Topography on the Plasma Jet Flow in the Substrate Boundary Layer under Suspension Plasma Spray Conditions: A Numerical Approach

Abstract This study deals with the numerical analysis of plasma jet behavior close to substrate surface depending on its topography. It uses a 2D axisymmetric time-dependent CFD model solved Ansys Fluent 2020/R1 package. The takes into consideration nonlinear thermophysical properties and turbulent phenomena as well interaction microtextured substrate. Representative topographies were considered boundary condition in simulations. They correspond bond coats used Thermal Barrier Coating technology, actually APS sprayed NiCrAlY coatings which experimentally using various laser unit operational conditions resulting different topographies. calculations showed that topography, modified controlled this work by microtexturing, disturbs homogeneity pressure field layer periodical fluctuation. was also observed relative local disturbance is more significant outer regions than centerline. Then, based results calculations, potential movement feedstock particles near discussed. concluded deposition fine powders, characterized low Stokes number, will be influenced distribution take place mainly high-pressure zones. Furthermore, swirl taking each microtexture, created here ablation, privileges such asperities. These observations show code modeling opens possibility predicting during spraying, essential for understanding coating mechanisms suspension spray.