Numerical Study of Plume Interference on Missile Bodies at Transonic Speeds

Strongly underexpanded jets may lead to the plume-induced shock and wall boundary layer separation on the afterbody surface of flight objects, resulting in doing harm to their maneuverability and deteriorating the overall perfomance. To understand the general physics on this area, numerical studies were conducted for the missile model with a rectangular base to simulate moderately and highly underexpanded exhaust plumes at transonic speeds. Fully implicit finite volume scheme was applied to mass averaged Navier-Stokes equations with a two-equation turbulence model, RNG k- e. The results showed that the plume-induced boundary layer separation on the missile afterbody was generated at high plume supply pressures and Mach number of 1.2. The plume-induced shock moved downstream movement as the free steam Mach number increased.