| Chemical oxygen-iodine laser (COIL) whose wavelength is 1.315μm is a continuous wave chemical laser. It is one of the highest energy output lasers at present. It consists of singlet oxygen generator (reacted fluids tank, collection tank, gas supplying system), oxygen-iodine mixing nozzle, optical cavity, diffuser and auxiliary system (freezing system, vacuum system etc). Singlet oxygen generator, which provides chemical energy for laser output, is the core component of laser. Its volume and weight account for more than 80% of whole laser. However, the application of the chemical oxygen-iodine laser, just as vehicle, airborne and space etc mobile platform, is limited for its relatively huge volume and weight. Therefore, lightening of chemical oxygen-iodine laser is inevitable for expanding its application. And lightening of singlet oxygen generator is the key. There are two ways to lighten singlet oxygen generator:one is increasing the volumetric efficiency and chemical efficiency, namely, increasing reactor flow per unit volume (calculated by Cl2 flow) and increasing yield of singlet oxygen (singlet oxygen flow generate by per unit Cl2 flow); the other is lightening the generator weight by using low density material instead of traditional stainless steel.Several technical innovations happened on singlet oxygen generator research:From the first generation of bubble-column generator, the second generation of rotating-plate generator, the third generation of jet generator to the forth generation of uniform droplet singlet oxygen generator. In contrast with the other generators, uniform droplet singlet oxygen generator which has higher volumetric efficiency and chemical efficiency is more suitable for mobile platform. Uniform droplet singlet oxygen generator was researched in this paper. Basic hydrogen peroxide formed uniform droplets in spacetime by the forced shock of piezoelectric oscillator. Based on this, a new reaction technology which enhanced mass and heat transmission in gas-liquid reaction was produced to increase the volumetric efficiency and reaction stability of generator. Generator structure and process conditions were optimized for higher yield of singlet oxygen by numerical simulation and experimental research. When the Cl2 flow is 0.5mol/s, Cl2 utilization ratio is 90.6%, and the absolute yield of O2(1△) is more than 50%. The concentration of O2(1△) reaches 2.94 which is higher than 2.5×1017mol/cm3-the reported index of uniform droplet singlet oxygen generator. Light extraction experiment was done on lOkW class laser driven by this generator. Output power reaches 9.55kW, and power density of nozzle reaches 121.3 W/cm2 when cold trap was not offered. It verified the high efficiency of uniform droplet singlet oxygen generator in spite of the small volume. In contrast with the most successful applied jet generator at present, generator's volume reduced by 1/3～1/2,and the usage amount of basic hydrogen peroxide reduced by 1/3～1/2 in the same Cl2 flow. The auxiliary system of generator was reduced which improved the miniaturization level of generator.In order to reduce the weight, carbon fiber composite was suggested to replace stainless steel to make singlet oxygen generator. Under vacuum conditions the max stress of liquid storage tank is 94.9MPa with latmsphere pressure loaded. which is far lower than the yield strength of carbon fiber composite. The max displacement is no more than 0.428mm which occurs on the top of tank—the connecting point with generator, it is feasible to make singlet oxygen generator by carbon fiber composite instead of stainless steel. Meanwhile,8 radialized fortifiable spokes were suggested to use on the generator vessel head to enhance the vessel head. A reaction tank which has equivalent application effect with stainless steel was made with carbon fiber composite, and its weight is only 1/4～1/3 of stainless steel made at the same volume. It is effective to use carbon fiber composite instead of stainless steel for generator manufaction. System weight was reduced greatly. A feasible technical route was shown clearly for lightening chemical oxygen-iodine laser.To verify the possibility of COIL's industry application, an experiment on aluminum and copper-zinc alloy surface radiated by laser was done. Samples melt in a twinkling by the laser energy. The diameter of laser is 6mm. power density is 10000-20000 W/cm2. Numerical Simulation of interaction of chemical laser with two component alloy was done based on Fourie thermal conduction mode through ANSYS in this paper. Numerical simulation results show that the aluminum began melt at 0.273s, a spherical cap molten pool whose diameter is 9.6mm, depth is 4.08mm was formed at last when the power density of laser is 17783 W/cm2: The copper-zinc alloy began melt at 0.393s, a spherical cap molten pool whose diameter is 6.4mm, depth is 1.64mm was formed at last when the power density of laser is 17950 W/cm2. The power density threshold value of aluminum melting is 4200-4500W/cm2,the power density threshold value of brass melting is 6100-7300 W/cm2. The simulation results above are consistent with the results of experiment. Damage extent of alloy radiated by COIL is related with power density of laser, radiated time and performances of material itself etc. According to the simulation results, appropriate process parameters of laser can be chosen in the practical application of material radiated by laser.
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