Modeling the Combustion of Opposed Flows of Butadiene and Air: A Skeletal Finite-Rate Chemical Kinetics Mechanism Derived from the San Diego Mechanism and Regression Rate Predictions for Hydroxyl-Terminated Polybutadiene-Air Systems
CCDC Army Research Laboratory Aberdeen Proving Ground United States
To evaluate the potential of a homogeneous-reactor HR-simulation-based implementation of the trial mechanism method TMM to produce skeletal finite-rate chemical kinetics mechanisms that are valid for modeling solid-fuel ramjet SFRJ combustor dynamics, one was employed to reduce the San Diego SD mechanism to produce candidates for modeling opposed-flow burner experiments involving hydroxyl-terminated polybutadiene HTPB and N2O2 mixtures. A candidate with 63 reactions and 33 species was vetted for the application. It was confirmed that when it was substituted for the full SD mechanism in HR simulations with initial conditions similar to those expected to be realized near HTPBs pyrolyzing surface, temperature and rate of heat release versus time histories produced with the full mechanism were reasonably reproduced. In addition, when it was substituted for the full mechanism in relevant opposed-flow diffusion flame simulations, key features, including the temperature gradient adjacent to the fuel inlet, the systems maximum temperature, and that temperatures location, were reasonably reproduced. In addition, HTPB regression rate predictions produced with the full mechanism and with the candidate were in reasonable agreement. The evaluation thus indicated that an HR-simulation-based TMM implementation can produce skeletal mechanisms that are valid for modeling SFRJ combustor dynamics.