The Impact of a Partially Molten YSZ Particle

Abstract

In plasma and high velocity oxy-fuel spraying, a certain portion of the injected powder is often not fully molten upon impact onto a substrate. We present numerical results of the impact of a partially molten yttria-stabilized zirconia particle, a material widely used as a thermal barrier. We consider an idealized scenario: the axisymmetric impact of a particle with a solid core, examining only the flow of the molten material around the core. The numerical method is based on the immersed boundary method for treating the interaction of solids and fluid within a computational domain. We present the results of a set of simulations, varying the particle and solid core diameters, and the impact velocity. When the core diameter is small relative to the particle, the impact behavior is similar to the impact of a fully molten droplet. When the core is larger, it promotes considerable splashing, which is undesirable.