Accession Number:

ADA409800

Title:

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

Descriptive Note:

Technical paper

Corporate Author:

AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE WEST

Personal Author(s):

Report Date:

1998-11-20

Pagination or Media Count:

18.0

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 andor 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 CON2. The effects of chamber pressure ranging from a subcritical i.e. relative pressure, Psub r PP sub injectant critical 1 to a supercritical P sub r 1 value at a supercritical chamber temperature relative temperature T sub r TT 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.

Subject Categories:

  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE