8th Thermal and Fluids Engineering Conference (TFEC)
An Initial Investigation of Endothermic Surface Emissions of Wake Bound Particles by means of Computational Fluid Dynamics
Densely loaded particulate flows represent a particularly interesting subset of fluid and fluid-structural dynamics due to the complex non-linear and interdependent physical phenomena involved. A novel usage of particles that exhibit endothermic, energy absorbing properties is for controlled dispersion of the particles within elevated temperature flows for a thermal protection system and/or wear reducing agent. The focus of this study is to observe the coupled effects of particles within the wake bound flow of a wedge-shaped surface feature in Mach 3.5 air flow. These mobile particles are directly modeled using an overset mesh technique and are simulated to exhibit endothermic surface emissions controlled by a temperature dependent reaction rate equation. Simulations are performed in 2d planar space, utilizing Ansys FLUENT CFD software. The current set of simulations vary the endothermic impetus, or strength, of the endothermic surface emissions, while observing qualitative data on general flow and particle behavior and capturing quantitative data on the kinematic properties of each individual particle. Through this analysis, it is shown that the motion of the particles exhibits a non-linear dependence on the strength of the endothermic emissions, and that effects such as local wall flow cooling are present due to convection of these emissions away from the particulate boundaries. The numerical results for these phenomena are presented, and suggestions for the genesis of these behaviors are discussed.