Characteristics of Radiation from a Q-Switched Supersonic Flow Chemical Oxygen-Iodine Laser

The flow and optical fields of a Q-switched supersonic flow chemical oxygen-iodine laser are simulated by solving simultaneously the gas flow model coupled with the precise chemical kinetic model and the geometric optical model. The effects of hyperfine relaxation and velocity cross relaxation for iodine atoms and nonuniformity of the three-dimensional flow field on power extraction are investigated. The results show that the peak power under the influence of hyperfine relaxation and velocity cross relaxation, which is normalized by the corresponding continuous wave value, is 15. This value agrees fairly well with previously reported experimental results of Q-switched chemical oxygen-iodine laser operations. The peak power of pulse in the three-dimensional flow field is considerably small compared to that in the equivalent one-dimensional flow field and the pulse is widened roughly twice due to insufficient mixing, shock waves, expansion waves and wakes.