Computational Fluid Dynamics of Complex Three-Dimensional Multiphase Flowfields

Extensions of a 3D upwind/implicit multiphase flow computer code (CRAFT) to simulate complex flow patterns associated with chemical/biological (C/B) agent release resulting from missile impact and from destruction of storage containers due to blast impact are proposed. The problems to be dealt with require the utilization of a time-accurate Navier-Stokes code with three-phase methodology (gas/bulk liquid/dispersed [droplet/particle] phase), multiphase combustion, the ability to numerically capture strong discontinuities (blasts/shocks/flames), and, a large eddy turbulent framework. Our starting framework is quite advanced and has been used to analyze very complex problems associated with transient solid/liquid rocket and gun propulsion. In Phase I, the framework for predicting in-situ destruction/dispersion of C/B agents will be established and demonstrated for both free and enclosed environments using present technology with limited upgrades. The Phase II program will focus on advanced upgrades (e.g. dynamic droplet formation modeling at gas/liquid interfaces, representation of non-Newtonian substances, etc.) required for improved simulation.