Multiheaded Rotating Detonation in an Annular Gap Under Variable Stagnation Pressure

Flows with multiheaded rotating detonation in a combustor in the form of an annular gap between plates are numerically studied. It is assumed that a homogeneous propane-air mixture enters the combustor from a reservoir with specified stagnation parameters through elementary nozzles uniformly filling the outer ring that limits it. The gas-dynamic parameters of this mixture are determined as functions of the stagnation parameters and static pressure in the gap. The study of multiheaded rotating detonation is carried out under the following conditions: the number of waves is 1, 2, 4, and 8, while the stagnation pressure slowly decreases over time according to a linear law. It is revealed that shock-wave structures can be qualitatively different, depending on the stagnation pressure, and that detonation ceases at a stagnation pressure lower than the critical pressure. The dependences of the power characteristics of the traction equipment on time are presented. Calculations are performed on the Lomonosov supercomputer at the Moscow State University using an original software package implementing a modified Godunov method and a one-step reaction kinetic model.