An experimental analysis of a cylindrical shock wave for use in a cylindrical gas dynamic laser.

Abstract

The goal of this research was to experimentally demonstrate the feasibility of a cylindrical shock wave to serve as the major pressure recovery mechanism for wither cylindrical gas dynamic lasers or chemical lasers. An analysis was conducted to determine the minimum distance between the nozzle exit cylinder and the shock wave locations, r(m)-r(e), required for power extraction. A cylindrical nozzle array was designed using the axisymmetric method of characteristics for a Mach number of 4.5 with a flexibility of other Mach numbers. A chamber incorporating end wall boundary layer bleed and ejectors for back pressure control was designed and built. The apparatus was run up to a pressure value of (r(m)-r(e))/(r(s)-r(e)) of 0.3 was attained, where r(s) is the shock wave location. Flow in the end wall nozzles consisted of a Conada jet with a subsonic flow region adjacent to the wall; flow was not altered by boundary layer bleed. Except for the end wall nozzles a cylindrical shock wave was established.