An Experimental Investigation of the Flow in an Interstage Connecting Duct for Use on a High Power Gasdynamic Laser. I. Gas Chromatograph Studies,

摘要

A model of a duct used to optically connect to high-power gasdynamic lasers was tested employing the USAF Academy trisonic wind tunnel. The wind tunnel was used as the cold flow simulation of the laser operating at Mach numbers of 3.5and 4.5,and at test section static pressures of 0.5to 0.8torr,and a mock-up of one half of the laser duct was attached to the wind tunnel test section. Gas chromatograph analysis of the flow composition at several locations in the duct resulted in the determination of the proper helium purge gas mass flow out of the duct which was necessary to keep the duct free of laser gas. The necessary purge gas mass flow was found to be sufficiently low enough so as not to adversely affect the laser diffuser performance. A similarity parameter allows correlation to actual laser conditions. (Author)