Highly efficient cw chemical oxygen—iodine laser with transsonic iodine injection and a nitrogen buffer gas

Abstract

Highly concentrated ozone gas, of greater than 20%, was applied, for the first time, in order to obtain a stable wettable polyimide film surface. The water contact angle of the polyimide film surface decreased from 60 to nearly 20 after exposure to the highly concentrated ozone gas. The increase in the small water contact angle during storage in ambient air was very gradual, i.e., 5 for over one month. Scanning electron microscopy and the atomic force microscope showed that surface roughening simultaneously occurred. Since the X-ray photoelectron spectra showed an increase in oxygen concentration at the polyimide film surface, the highly concentrated ozone gas is considered to produce a wettable surface by the significant oxidation of the polyimide film chains on the surface.

Modeling of cw OIL energy performance based on similarity criteria

“…Based on these data, the similarity criteria , , and energy efficiency d τ Π Λ ( ) cal. η are found by the solution of system of the equations (15) and (16) with use (5). The values of , and d τ Π Λ presented in Table 2 are found with the accuracy about 20 % because of inaccuracy in measurements of atomic iodine concentration and gas temperature.…”

Problems of COIL fluid dynamics

“…Early numerical results [4] obtained with RANS k-ω SST model exhibits overestimated small signal gain (SSG). One of possible reason for this is non-stationary effects which were not taken in account in highly-symmetrical simulation.…”

“…Of course it is not enough for deep understanding of flow structures. 3D RANS based on k-ω SST model with standard kinetic package like in [4] is proved to be valid for the COIL diffuser simulation. Verification procedure is based on the two approaches: (1) grid convergence and (2) comparison with real 15-kW COIL experiments [4].…”

“…3D RANS based on k-ω SST model with standard kinetic package like in [4] is proved to be valid for the COIL diffuser simulation. Verification procedure is based on the two approaches: (1) grid convergence and (2) comparison with real 15-kW COIL experiments [4]. Unstructured grid adapted to the flow structure I j f. and refined in high-gradient areas allows getting grid-converged solution.…”

3.7 Iodine lasers

“…A subsonic system in the Institute of Physics, Prague, Czech Republic, attained 50-100 W in a continuous regime [91Sch] and was also operated in a repetitive (1.3-4 kHz, 250 W peak power) magnetically switched regime [94Sch], now a supersonic upgrade renders 0.5 kW cw power [04Spa]. An experimental system at the Lebedev Institute branch, Samara, Russia, had originally 170 W, now it reaches 770 W of cw power [96Nik,05Nik], elsewhere in Russia, the Russian Federal Nuclear Centre, VNIIEF Arzamas 16 -Sarov, Russia, operate a chemical iodine laser system at 3.4 kW [05Vys] and a large cw system of 13.5 kW was recently reported by a joint team of Voenmekh Baltic State Technical University and Laser Systems Ltd. at St. Petersburg [05Bor]. At the Korea Atomic Energy Research Institute, Taejon, Korea, a system of 2.2 kW is in operation [00Kwo], another system in India, Delhi, gives 5 kW [03Tya].…”