MODELING OF DUST ENTRAINMENT BY HIGH-SPEED AIR-FLOW

An analytical model for dust lofting due to shock waves or high speed (> 100 fps) winds is described. The model divides the dusty boundary l ayer into two rigions, an inner granular flow region where particle im pacts dominate and an outer region where turbulent diffusion dominates , The two regions are linked by specifying appropriate boundary condit ions at a matching point. The effect of surface cohesion is modeled wi th a parameter representing the energy necessary to fluidize the surfa ce material. The model has been implemented into the MAZe: (multiphase adaptive zoning) hydrocode, As a validation of the model, the code wa s used to simulate a wind-tunnel dust lofting experiment. The model pr oduced good agreement with experimental mass lofting rates and vertica l dust loading profiles.