Transient, Rocket Exhaust Plume Modeling for Static Test Analyses

Our proposal addresses the high fidelity modeling of transient rocket exhaust plumes in a static test environment. Static testing provides a practical means of obtaining plume signature data to support model validation. However, existing CFD codes routinely used for plumes in flight cannot accurately address many of the complexities associated with a static test environment. Our starting point will be an advanced state of the art Navier-Stokes code that contains much of the requisite physics (chemistry, multiphase particulates, condensation, etc.) and operates in a dynamic grid framework. In Phase I, we investigated the use of all-speed preconditioning techniques for mixed regions of high and low speed flow. A technical approach was formulated to efficiently model rocket motors exhausting into quiescent environments including the effects of the test stand, surrounding terrain, prevailing wind, physical phenomena such as buoyancy, and secondary smoke formation. In Phase II we will incorporate models simulating these effects into our Navier Stokes code and analyze realistic static test firing problems. Work on the development of hybrid RANS/LES turbulence models for static test analyses will also be conducted to more accurately model transient turbulent structures and multiphase particulate phenomena present in these complex transient flowfields.