A Comparison of the Nonlinear Unsteady Responses of Two Classical Models for Solid Propellant

The nonlinear characteristics of unsteady combustion of solid propellants are investigated numerically. The adopted mathematical models are the quasi-steady homogeneous one-dimensional (QSHOD) model and the Zel'dovich-Novozhilov (ZN) model, widely used in combustion instability study. A numerical algorithm based on the spectral decomposition is constructed for the two models according to their similar governing equations. The different dynamical features of the two models driven by the pressure excitation are compared. The results show the responses of the two models are still qualitatively equivalent in nonlinear region but quantitatively different.