Initial Growth Rate and Visual Characteristics of a Round Jet into a Sub- to Supercritical Environment of Relevance to Rocket, Gas Turbine, and Diesel Engines

Abstract

The combustion chamber temperature and pressure in many liquid rocket, gas turbine, and diesel engines are quite high and can reach levels above the critical point for the injected fuels and/or oxidizers. A high pressure chamber is used to investigate and understand the nature of the interaction between the injected fluid and the environment under such conditions. Pure N2 He, and O2 fluids are injected. Several chamber media are selected including, N2, He, and mixtures of CO+N2. The effects of chamber pressure ranging from a subcritical (i.e. relative pressure, P(sub r) = P/P (sub injectant critical < 1) to a supercritical (P sub r > 1) value at a supercritical chamber temperature (relative temperature T sub r = T/T sub injectant critical >1) are photographically observed and documented near the injector hole exit region using a CCD camera illuminated by a short-duration back-lit strobe light. At low subcritical chamber pressures, the jets exhibit surface irregularities that amplify downstream, looking intact, shiny, but wavy (sinuous) on the surface that eventually break up into irregularly-shaped small entities.

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Document Details

Document Type
Technical Report
Publication Date
Nov 20, 1998
Accession Number
ADA409800

Entities

People

  • B. Chehroudi
  • D. Talley
  • E. Coy

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Biomedical
  • Materials and Manufacturing Processes
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force Research Laboratories
  • Combustion
  • Combustion Chambers
  • Critical Temperature
  • Froude Number
  • Gas Turbines
  • Heat Energy
  • Heat Of Vaporization
  • Heat Transfer
  • Latent Heat
  • Measurement
  • Phase Transformations
  • Pitot Tubes
  • Pressure Measurement
  • Reynolds Number
  • Turbines
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.