Cw Chemical Oxygen Iodine Laser Research Articles

Chemical oxygen-iodine laser with external production of iodine atoms in CH3I/Ar dc glow discharge

A cw chemical oxygen-iodine laser (COIL) operating in a subsonic mode with a high water content of ∼15% and external production of iodine atoms in CH3I/Ar dc glow discharge has been demonstrated. A straightforward comparison of COIL performance for two cases—conventional, when I2 was injected in the singlet oxygen flow, and when iodine atoms produced externally together with other discharge products were injected—was made. In the latter case nearly four times increase in output power was observed, suggesting that the relaxation of the energy stored in the singlet oxygen slowed down substantially, when the laser operated using CH3I/Ar discharge products instead of iodine molecules.

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

Methods of increasing the efficiency of low-pressure chemical oxygen—iodine lasers (COILs) with transsonic injection of molecular iodine, in which nitrogen is used as a buffer gas, are studied. A two-layer gas-dynamic model is used for a parametric analysis of physicochemical processes occurring in the transsonic iodine injector and in the COIL resonator, including mixing and generation of radiation. The 3D-RANS computer simulation software is used to study the flow structures resulting from an injection of iodine-containing flow into the transsonic zone of the oxygen nozzle. Experiments with a 10-kW modified laser have resulted in a chemical efficiency of 31.5% for a lasing power of 13.5 kW. The results of experimental studies of the cryosorption COIL exhaust system are presented.

Temporal and 2-D small-signal gain measurements in a supersonic COIL

A dedicated CW chemical oxygen iodine mini-laser is constructed and used to probe the two-dimensional (2-D) distribution of small-signal gains in a supersonic CW chemical oxygen iodine laser (CW COIL). The uneven lateral gain distribution may possibly be explained by boundary layer effects.

Pulsed chemical oxygen—iodine laser with bulk formation of iodine atoms by an electric discharge

A preliminary investigation was made of a chemical oxygen—iodine laser with bulk formation of iodine atoms in an electric discharge. The output energy was comparable with that obtained for a photolysis variant of the laser, but the technical efficiency of the investigated discharge variant was much higher (91%). The pulse power (~100 kW) was approximately three orders of magnitude higher than the power of a cw chemical oxygen—iodine laser with the same chlorine flow rate.

Experimental investigation of chemical oxygen-iodine laser

Results of an experimental investigation of a chemical oxygen-iodine laser (COIL) are presented. We determine the factors influencing the efficiency of a chemical singlet-oxygen generator (SOG) of the bubbler type operating on the chlorination of an alkaline solution of oxygen peroxide. We describe SOG constructions. A cw COIL with output power up to 400 W is developed on the basis of the investigated SOG. The feasibility of a modular construction of high-power COIL is demonstrated. A power-output level of 1 kW was achieved with a two-section laser. The feasibility is analyzed of COIL operation in a pulsed regime by pulsed bulk accrual of iodine atoms. We show that in this regime the laser can be operated without a low-temperature trap. An advantage of such a regime is also the possibility of controlling, in a wide range, the lasing pulse duration. A strong influence of molecular chlorine on the energy content of the active medium is observed when alkyliodides are used as iodine donors. The possibilities of using a pulsed COIL for controlled thermonuclear fusion are discussed.

Experimental and theoretical study of a high-power c.w. chemical oxygen iodine laser(COIL)

A theoretical analysis of a kilowatt class COIL system has been performed in order to explain its output power limitation in the range of 600 watts.The influence of the excessive water vapour content on laser output power was studied using two theoretical models. The theoretical and experimental results confirm that decreasing the water vapour concentration by a factor of 2,allows to reach the kilowatt power levels

Experimental study of gain and output coupling characteristics of a CW chemical oxygen-iodine laser

Gain and output coupling characteristics of the CW chemical oxygen-iodine laser (COIL) are determined experimentally by means of varying the output coupling method. Under the conditions that the Cl/sub 2/ flow rate is 11.8 mmol/s, the I/sub 2/ molar flow rate is from 20 to 50 mu mol/s, and the duct pressure is 200 Pa, the following were obtained from the experimental data: maximum values of output power of 58 W, and optimal output coupling factor of 1.50%, a resonator efficiency of 4.8%, an unsaturated small-signal gain of 1.55*10/sup -3/ cm/sup -1/, a threshold small-signal gain of 1.31*10/sup -3/ cm/sup -1/, a saturation intensity of 1150 W/cm/sup 2/, intraresonator losses of 9%, and an atomic iodine concentration of 2.85*10/sup 14/ cm/sup -3/. A comparison of these results to the published data of other COIL systems is presented. >

Moderate-power cw chemical oxygen-iodine laser capable of long duration operation

Design and operation of a cw, transverse-flow oxygen-iodine chemical laser are reported. Reactant recirculation in the O2(1Δ) chemical generator allows long duration (up to 2 h) operation. Peak powers of 460 W, and stable outputs of 80 W have been demonstrated. Power extraction efficiencies of up to 65% were measured for 80-W operation, and the implications of this observation for the I2 dissociation mechanism are discussed.

Numerical modeling of a chemical oxygen–iodine laser

A calculation is reported of the specific output energy and of the gain of a cw chemical oxygen–iodine laser. An allowance is made for the influence of quenching impurities present in the active medium. Conditions are found for achieving simultaneously high values of both the specific output energy (~100 J/g) and of the gain [(2–4)×10−3 cm−1]; this should make it possible to use resonators with a high coupling coefficient (0.3–0.5).