Effects of wall catalysis on the reacting zone structure of a supersonic flow chemical oxygen-iodine laser

The flow field of a supersonic how chemical oxygen-iodine laser is simulated by solving the three-dimensional full Navier-Stokes equations, and the dependence of the mixing/reacting zone structure and the resulting gain region on the penetration depth of I-2 jet into the primary flow of singlet: delta oxygen O-2((1)Delta) is investigated. The effects of wall catalysis are discussed by introducing the surface catalytic efficiency into the wall boundary condition. It is shown that an optimum condition for the secondary It jet momentum exists, and that the jet that causes a high gain penetrates the primary flow up to an intermediate depth and does not collide with the counter one. It is also shown that the molar fractions of I(P-2(1/2)) and O-2((1)Delta) are reduced markedly on the fully catalytic wall. The deactivated oxygen molecules are engulfed by the vortices generated behind the I-2 jet, leading to the presence of a large amount of unconsumed It, the reduced formation of I(P-2(1/2)) and a large negative gain region in the center of the vortices even far downstream of the nozzle blades. The present study demonstrates the importance of the choice of wall material.