Plume-on base drag prediction including three-dimensional and real-gas effects

A multicomponent method to predict base drag in base flow/plume interaction problems has been formulated, implemented, and validated. The formulation accounts for real-gas effects in the nozzle and in the plume as well as for three-dimensional effects associated with small angle of attack (up to 10 deg) conditions. Its application is intended for both launcher configuratio n analysis and missile drag prediction. Development of this methodology has been carried out to fill in the category of tools that are located between semi-empirical methods and computational fluid dynamics (CFD) algorithms. The technique being used consists of dividing the flowfield into several su bregions that are solved separately and, subsequently, matched together in an iterative self-consistent way. Validation of the method has been perform ed by comparing the multicomponent method results with experimental and CFD data in a series of cases.