Erosion prediction near a stagnation point resulting from aerodynamically entrained solid particles

The study treats the problem of determining the particle trajectories near a stagnation point of a two-phase gas-solid mixture flow. This is a critical area arising in a corner flow, flow into a flat plate, and flows over closed bodies such as cylinders and blades. An analytical model is developed to predict erosion occurring near the stagnation point. The model takes account of the aerodynamic drag on the particles, the impact angle speed, and density, and determines the material removal along the wall. The solution is of closed-form type and based on analysis of a single particle; it is readily applicable to a distribution of any number of like particles. However, when the number of particles becomes large, the continuous phase is altered and the assumption of continuous phase invariance under particle flows becomes invalid. It is found that the momentum equilibration parameter is the unique criterion for predicting particle trajectories, and that erosion is proportional to the particle velocity raised to the mean exponent of 3.83.