Numerical Simulation of Combustion of Unlike Impinging Jets Near a Wall

The combustion of gas-gas hypergolic propellants with MMH (Monomethylhydrazine) as fuel and RFNA (Red fuming nitric acid) as oxidizer are studied numerically for unlike impinging jets near an inclined wall using a detailed chemical reaction mechanism. The current study focuses on quantifying the effect of the inclined wall on the ignition characteristics: namely, contact time/location and ignition delay/location. Furthermore, the effect of wall is assessed with respect to mixing and flame spreading. The baseline three-dimensional simulation results compare two domains, with and without the inclined wall, under the same inlet flow conditions. These results show that the space between the wall surface and injector tips acts as a mixing zone with intensified vorticity and heat release rate. Two-dimensional results for various injection velocities are also presented and are compared with the three-dimensional results. The original document contains color images. Supported in part by ARO.