Mixing and Reacting Zone Structure in a Supersonic Mixing Chemical Oxygen-Iodine Laser with Ramp Nozzle Array

The adoption of a ramp nozzle array in supersonic mixing chemical oxygen-iodine lasers is examined by simulating the mixing and reacting flow fields numerically. Then, the efficiency of the ramps in improving the resulting gain region is studied. The compressible Navier-Stokes equations with a detailed chemical kinetic model are solved using a full-implicit finite volume method. The numerical results show that streamwise vortices, which were not anticipated in the previous studies, are induced downstream of the base relief region of the ramp nozzle array and significantly accelerate the mixing and reaction. The contact surface between the reactant streams is stretched very rapidly due to the vortices, resulting in much higher laser performance.