Representative interactive flamelet model and flamelet/progress variable model for supersonic combustion flows

Abstract

Two flamelet-type models are developed for supersonic combustion flows. First, the representative interactive flamelet (RIF) model is introduced to fully incorporate the local high-Mach-number effects into the flamelet library, and some algorithms specifically for supersonic flows are designed in the RIF model. Secondly, the flamelet/progress variable (FPV) model is also extended to supersonic combustion flows, based on a new compressible rescaling for the tabulated chemical source term of the progress variable. These two models, together with the steady flamelet (SF) model, are then applied in a supersonic combustion experimental case. Numerical results indicate that the RIF model induces very limited changes on the temperature and major species concentrations compared to the SF model, implying that the species concentrations in the flamelet library are not sensitive to the local high-Mach-number effects. Overall, the RIF model does not show obvious improvement on the simulation accuracy for the studied case. While for the FPV model, the obtained numerical results achieve much better agreements with the experimental data, including the temperature, major species concentrations and auto-ignition position. It is also found that the proposed compressible rescaling for the FPV model reasonably incorporates the high-Mach-number effects on the tabulated chemical source term of the progress variable and effectively improves the simulation accuracy of the FPV model for supersonic combustion flows.