In this study, a 3D two-way coupled Eulerian-Lagrangian approach is used to model the plasma jet and droplet-particle trajectory, velocity, and temperature achievable by suspension plasma spraying. A Reynolds stress model is used to account for turbulence and the effect of the substrate on the flow field and a Kelvin-Helmholtz Rayleigh-Taylor breakup model is used to predict the secondary breakup of the suspension. The focus of this work is on particle behavior near the substrate. Flat substrates placed at stand-off distances ranging from 40 to 60 mm are modeled to provide detailed information on particle impact behavior.

This study compares two methods for modeling the breakup of droplets during suspension plasma spraying. One is based on Taylor analogy breakup, the other on Kelvin-Helmholtz Rayleigh Taylor breakup. A three-dimensional model with two-way coupling is used to simulate flow within the plasma plume and interactions between suspension droplets, and a Reynolds stress model is used to simulate gas field turbulence. After breakup and vaporization, the solid suspended particles are tracked through the domain to determine the characteristics of coating particles. The numerical results are validated against experiments using high-speed imaging.