The F2 wind tunnel at Fauga-Mauzac

Details on the French subsonic wind-tunnel F2 that becomes operational on July 1983 are presented. Some of the requirements were: (1) installation of models on any wall of the facility, (2) good observation points due to transparent walls, (3) smooth flow, (4) a laser velocimeter, and (5) easy access and handling. The characteristics include a nonpressurized return circuit, dimensions of 5 x 1.4 x 1.8 m, maximum velocity of 100 m/s and a variable speed fan of 683 kW

Reliability of metal/glass-ceramic junctions made by solid state bonding

The solid state diffusion bonding leads to helium-tight ceramic-metal junctions. However this technique induces residual stresses due to expansion mismatches which may cause ceramic flaws to propagate hence junction delayed failure. This phenomenon is evidenced on glass-ceramic/Al/Invar junctions from which a better reliability is ensured by a reduction of surface flaws

RELIABILITY OF METAL/GLASS-CERAMIC JUNCTIONS MADE BY SOLID STATE BONDING

L'assemblage par diffusion dit par thermo-compression permet de réaliser des liaisons céramique-métal étanches à l'hélium. Ce procédé engendre cependant des contraintes résiduelles d'origine thermique sous l'action desquelles les défauts de la céramique peuvent se propager et conduire à la rupture différée de l'assemblage. Ce phénomène est mis en évidence sur des assemblages vitrocéramique/Al/Invar où une meilleure fiabilité est assurée par une réduction des défauts de surface.The solid state diffusion bonding leads to helium-tight ceramic-metal junctions. However this technique induces residual stresses due to expansion mismatches which may cause ceramic flaws to propagate hence junction delayed failure. This phenomenon is evidenced on glass-ceramic/Al/Invar junctions from which a better reliability is ensured by a reduction of surface flaws

Nouveaux moyens d'essais hypersoniques developpes a l'ONERA Les souffleries R5 et F4

Communication au Symposium AGARD 'Theoretical and experimental methods in hypersonic flows', Turin (Italie), 4-8 mai 1992Available at INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.1992 n.39 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc