CW HF laser with supersonic premixing and stationary shock initiation. Final report 1 Jun 75-31 Dec 76

Technical Report · Fri Apr 01 04:00:00 EST 1977

OSTI ID:5268170

Moran, J P; Kolb, C E

Formation of HF by the chain reaction is initiated by the simultaneous reaction NO + F/sub 2/ yields NOF + F. A detonable mixture of the reactants, H/sub 2/, F/sub 2/, and NO in argon or helium diluent, is achieved by secondary injection of H/sub 2/ and NO along the trailing edges of a two-dimensional nozzle array into a cold supersonic stream of premixed F/sub 2/ plus diluent. Mixing of the secondary injectants is achieved without significant chemical reactions in slightly divergent supersonic mixing section. The resultant detonable mixture is directed into a chamber as a slightly underexpanded free jet. This free jet is interrupted shortly downstream of its exit plane by a nearly normal shock wave. The shock is held in a stationary manner by a shock holder which accepts only a portion ( approximately 70%) of the total jet flow. An adjustable sonic throat, within the shock holder, controls the accepted fraction. Laser mirrors in a fixed stable-cavity configuration constitute two walls of the shock holder. Maximum laser cavity intensity, sampled through several small holes in one mirror, presently appears to be in excess of 51 W/sq cm, as deduced from measurements of power in excess of 117 mw incident on a PbSe detector. Laser power output in excess of 20W, in a closed cavity configuration, was determined from local mirror heating by thermocouple measurements. This work represents the first success in achieving a stationary shock in a detonable mixture in a configuration other than a free jet. Furthermore, it represents the first demonstration of CW laser operation across a stationary shock.

• Research Organization: Aerodyne Research, Inc., Bedford, Mass. (USA)
• OSTI ID: 5268170
• Report Number(s): AD-A-041779; ARI-RR-105
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
CHALCOGENIDES
CHEMICAL LASERS
CHEMICAL REACTIONS
HYDROFLUORIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
LASERS
NITROGEN COMPOUNDS
NITROGEN OXIDES
OPERATION
OXIDES
OXYGEN COMPOUNDS