Cold Flow Testing of a Modified Subscale Model Exhaust System for a Space Based Laser

Abstract

The aim of this research was a continued study of gas-dynamic phenomena that occurred in a set of stacked nozzles as reported by Captains Ian Bautista in 2003 and Scott Bergren in 2002. The arrangement of the stacked nozzles was a modified version of a 1/5th scale-model of one quadrant of the conceptual Space Based Laser Integrated Flight Experiment (SBL IFX) gas dynamic laser. Rather than cylindrical rings of nozzles, the stacked nozzles were flat and able to be rotated about a vector normal to the nozzle exits. This set of stacked flat nozzles was installed on a blow-down/vacuum wind tunnel, which in addition to the nozzles, consisted of a stilling chamber, centerbody, supersonic diffuser, and transition structure to join the vacuum and test sections. The goals of this research were two fold; first, modify the original scale-model of the stacked cylindrical rings of nozzles so schlieren photography could be used to visualize an average flow field across the nozzles. Secondly, using the schlieren photographs, in conjunction with pressure data, observe the interactions between the individual nozzles. Results have shown that the modified nozzle array produces a vastly complex flow field as well as a highly supersonic flow r gime, with Mach numbers that reach as high as 5.6.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 2004
Accession Number
ADA426656

Entities

People

  • David B. Jarrett

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Boundary Layer
  • Cameras
  • Exhaust Systems
  • Flow Fields
  • Fluid Dynamics
  • Fluid Flow
  • Gas Dynamic Lasers
  • Lasers
  • Light Sources
  • Mach Number
  • Photographs
  • Photography
  • Pressure Measurement
  • Test Facilities
  • Turbulent Mixing
  • Wind Tunnels

Readers

  • Combustion and Flow Dynamics.
  • Fluid Dynamics.

Technology Areas

  • Directed Energy
  • Hypersonics
  • Hypersonics - Hypersonic Flow
  • Space
  • Space - Hall-Effect Thruster