A Method of Characteristics Solver for Unsteady Quasi-One-Dimensional Chemically Reacting Gas Flows

摘要

The unsteady, inviscid, quasi-one-dimensional flow of chemically reacting mixture of gases was modeled based on the method of characteristics (MoC). Gaseous mixtures were assumed to be in thermal equilibrium but no such restrictions were placed on the chemical time scales, that is, frozen, equilibrium or non-equilibrium chemistry can be simulated. The variables associated with chemical composition were evaluated using the open-source toolkit Cantera. Numerical integration of the resulting ordinary differential equations from MoC was carried out using an explicit, second-order Euler predictor-corrector method for the gasdynamic equations, while the chemical rate equations were evaluated using ode 15s available in MATLAB™. Validation studies were performed by simulating three cases, namely, supersonic combustion, reactive flow behind a normal shock and chemical non-equilibrium flow in hypersonic nozzle and the results agreed well with the data available in the literature.