Multiphase CFD Analysis of Solid Rocket Motor Nozzle and Plume Flow

Abstract

Specialized computer models have been developed by others, to predict the multiphase flow through SRM nozzles, as well as the rocket plu me. In this study, two approaches are discussed for calculating the effects of a particul ate phase on the nozzle and plume flow in the continuum regime. The focus of the work is the comparison of computational fluid dynamics (CFD) models in which the particulate phase is calculated in either a Langrangian or Eulerian reference frame, and the discussion of the multiphase nozzle and plume flow dynamics observed. Steady-state, compressible, non-reacting, turbulent, multiphase flow is assumed. Phase change and radiative heat transfer are not considered. The properties, size distribution, and mass loading for the particulate phase are assumed and kept constant. A conical nozzle profile is chosen with assumed inlet flow conditions (including a 30% particulate mass loading), and the multiphase nozzl e flow is compared with a solution obtained using a specialized computer model. The plume is then expanded into an initially ambient environment, and the multiphase plume flow resulting from the CFD solutions on two different computational grids is discussed. Co mplex mean flow effects were modeled and shown to have great importance in compressible multiphase nozzle and plume flow simulations. The methodologies presented are general and can be applied to 3D and parallel computations.