Numerical analysis of unsteady multiple jet plume interactions

摘要

The prediction of the transient behavior of multiple jet plume systems is important in engineering problems such as those encountered in solid rocket motor (SRM) design. Many SRMs employ a pyrogen-type ignition system, which consists of one or more hot exhaust plumes that induce burning in the motor propellant grain through impingement and subsequent heat transfer. Experimental cold-flow studies have indicated that aerodynamic plume-on-plume interactions, as well as plume-on-wall interactions, can significantly modify the heat transfer to the propellant grain. Such interactions are studied here with a computational model previously utilized in the study of unsteady confined supersonic jets. The model uses a MacCormack explicit, predictor-corrector finite-difference solution of the unsteady, compressible, full Navier-Stokes equations, coupled with a two-equation k − ε turbulence model. A parametric study of the transient behavior of multiple plume systems is performed and the degree of interaction between the plumes is investigated.