Extended, Transient Rocket Exhaust Plume Modeling

The extended transient exhaust plume from hypervelocity tactical missiles contains particles, which degrade EM waves used for guidance and/or tracking. Our proposed Phase II effort continues the development of an efficient parallel architecture frameworkto analyze the complete transient plume, from launch to target, using specialized Navier-Stokes methodology in a dynamic and expanding grid system. A multiple grid and/or time-scale formulation is proposed to treat the disparate scales in the plumenearfield and farfield domains. Launcher interactions will be investigated and ground effects such as dust and blowing sand will be investigated. Efficiency strategies will be examined using a sequence of quasi-steady solutions as well as a translating,expanding grid system. Multiphase enhancements will include continuing the inclusion of RANS particle dispersion methodology utilizing a Lagrangian particle solver with stochastic methods to emulate the turbulent eddy structure. A framework for modelingsecondary smoke formation will be developed. Demo calculations will be performed for a CKEM type missile over a complete trajectory.The ability to deal with the extended transient plume problem has significant commercial potential as related to a varietyof dispersion problems which include:(1) dispersion of noxious elements from rocket boosters during launch;(2) exhaust plume products from rocket/missile launchers as related to IR and structure interaction problems:(3) Varied commercial smokestack dispersion problems; and,(4) Chem/Bio bunker venting and threat missile post-hit cloud dispersion scenarios.This effort will expand the types of problems we can support and will enhance the commercialization of specialized codes we now license.