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Title: Optimisation of characteristics of a chemical HF laser operating by using a new method for oxidising-gas production

Abstract

The energy parameters of an HF laser operating by using a new method for oxidising-gas production, which is based on the principle of two-region mixing, are optimised. The total amount of the inert diluent (helium) supplied to the laser was varied during experiments by varying its relative fraction only in the second mixing region. For an optimal relative fraction of the diluent in the second mixing zone and for an optimal position of the optical axis of the cavity under a constant pressure in the gas generator, the laser radiation power and the specific power output could be increased by 50% and 60%, respectively, compared to the laser operation regime realised in our previous experiments. In this case, the inert diluent amount decreased by 35% and the length of the generation region increased by 20%. (lasers)

Authors:
; ; ; ; ; ;  [1]
  1. Russian Science Centre 'Applied Chemistry', St Petersburg (Russian Federation)
Publication Date:
OSTI Identifier:
21456925
Resource Type:
Journal Article
Resource Relation:
Journal Name: Quantum Electronics (Woodbury, N.Y.); Journal Volume: 36; Journal Issue: 12; Other Information: DOI: 10.1070/QE2006v036n12ABEH013249
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; GAS GENERATORS; HELIUM; HYDROFLUORIC ACID; LASER CAVITIES; LASER RADIATION; LASERS; OPERATION; OPTIMIZATION; OXIDIZERS; ELECTROMAGNETIC RADIATION; ELEMENTS; FLUIDS; FLUORINE COMPOUNDS; GASES; HALOGEN COMPOUNDS; HYDROGEN COMPOUNDS; INORGANIC ACIDS; INORGANIC COMPOUNDS; NONMETALS; RADIATIONS; RARE GASES

Citation Formats

Rebone, Vitalii K, Fedorov, Igor' A, Maksimov, Yurii P, Mitryaev, V A, Rotinyan, Mikhail A, Tret'yakov, Nikolai E, and Etsina, Alla L. Optimisation of characteristics of a chemical HF laser operating by using a new method for oxidising-gas production. United States: N. p., 2006. Web. doi:10.1070/QE2006V036N12ABEH013249.
Rebone, Vitalii K, Fedorov, Igor' A, Maksimov, Yurii P, Mitryaev, V A, Rotinyan, Mikhail A, Tret'yakov, Nikolai E, & Etsina, Alla L. Optimisation of characteristics of a chemical HF laser operating by using a new method for oxidising-gas production. United States. doi:10.1070/QE2006V036N12ABEH013249.
Rebone, Vitalii K, Fedorov, Igor' A, Maksimov, Yurii P, Mitryaev, V A, Rotinyan, Mikhail A, Tret'yakov, Nikolai E, and Etsina, Alla L. Sun . "Optimisation of characteristics of a chemical HF laser operating by using a new method for oxidising-gas production". United States. doi:10.1070/QE2006V036N12ABEH013249.
@article{osti_21456925,
title = {Optimisation of characteristics of a chemical HF laser operating by using a new method for oxidising-gas production},
author = {Rebone, Vitalii K and Fedorov, Igor' A and Maksimov, Yurii P and Mitryaev, V A and Rotinyan, Mikhail A and Tret'yakov, Nikolai E and Etsina, Alla L},
abstractNote = {The energy parameters of an HF laser operating by using a new method for oxidising-gas production, which is based on the principle of two-region mixing, are optimised. The total amount of the inert diluent (helium) supplied to the laser was varied during experiments by varying its relative fraction only in the second mixing region. For an optimal relative fraction of the diluent in the second mixing zone and for an optimal position of the optical axis of the cavity under a constant pressure in the gas generator, the laser radiation power and the specific power output could be increased by 50% and 60%, respectively, compared to the laser operation regime realised in our previous experiments. In this case, the inert diluent amount decreased by 35% and the length of the generation region increased by 20%. (lasers)},
doi = {10.1070/QE2006V036N12ABEH013249},
journal = {Quantum Electronics (Woodbury, N.Y.)},
number = 12,
volume = 36,
place = {United States},
year = {Sun Dec 31 00:00:00 EST 2006},
month = {Sun Dec 31 00:00:00 EST 2006}
}
  • The energy and spectral characteristics of an HF laser operating by using a new method of obtaining the oxidising gas based on a two-region mixing are studied experimentally. The investigation involved redistribution of the overall amount of the rare-gas diluent (helium) delivered to the laser between the gas generator (the first mixing region) and the subsonic parts of the nozzles of the nozzle unit (the second mixing region). In this case, the temperature in the gas generator was maintained constant and the experiments were conducted under conditions when either the mass flow of atomic fluorine or the pressure in themore » gas generator were maintained constant. It was shown that upon a nearly full transfer of helium from the first mixing region to the second one in the constant-pressure regime in the gas generator, the laser output power increased by 70%, while in the regime of a constant mass flow of atomic fluorine, the output power increased by 14% along with a simultaneous increase in the specific energy extraction by 40%. The lasing region was found to lengthen by no less than 35%. (lasers)« less
  • Self-induced transparency (SIT) of HF laser radiation at lambda 2.7 ..mu..m has been observed in low-pressure HF gas for several P/sub 1/(J) transitions. Low-loss propagation through the resonantly absorbing medium was observed, and intensity threshold values for the onset of SIT were found to agree with those predicted by theory. Laser pulses of high peak power and/or long duration were found to break up into several individual 2..pi.. pulses. The resulting frequency of modulation in the output waveform was in quantitative agreement with theory and the damping of the modulation envelope was in agreement with the rotational relaxation time ofmore » the HF transition. Measurements showed that the velocity of propagation of the laser pulse through the HF gas at millitorr pressures was as little as 1/40 the speed of light in vacuum.« less
  • An experimental investigation was made of the energy and gasdynamic characteristics of a supersonic cw chemical HF laser with a radial-expansion (nozzle-sonic injector) nozzle array of 35 cm x10 cm dimensions. The two types of secondary-fuel feed collector differing in respect of the angular orientation of the hydrogen injector axes relative to the direction of flow of the oxidant gas. The Mach number, the static pressure, and the total pressure distributions behind a plane shock wave were determined in the field of flow of the active medium. Injection of the additional hydrogen jets into the oxidant gas stream intensified mixingmore » of the reactants, increased the specific output energy by 10%, and improved homogeneity of the gasdynamic parameters of the active medium. (lasers and amplifiers)« less
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