Investigation of Volume-of-Fluid Method to Simulate Melting-Solidification of CMAS Particles

The ingestion of CMAS (Calcium-Magnesium-Alumino- Silicate) particles into aircraft engines is an issue for both the safety and resilience of aircraft. CMAS ingestion process can erode compressor blades, erode/infiltration thermal barrier coatings, and lead to overheating and stall. To better understand the physical details, this paper presents a novel approach to exploring individual CMAS dynamics in the context of melting particles. The methodology was accomplished by resolving the details of a single CMAS particle using the volume-of-fluid method. To account for thermal properties of the flow and particle, melting-solidification modeling was implemented. The particle was initialized at a stagnant condition with a temperature under its solidus temperature. The flow around the particle was initialized at turbine relevant conditions, including high velocities and temperatures above the particle's liquidus temperature. Transient conditions were explored in context of non-dimensional numbers (including slip Reynold's Number, Weber number, and Ohnesorge number), as well as several ratios (ρs/ρg and Ts/T∞). For validation, sensitivity to mesh and input, as well as experimental comparisons were examined. The experimental comparison benchmarked the temperature ratio of particles at varying thermal Stokes numbers against the experimental correlation shown in Bojdo et al. [1].