MECHANICAL VIBRATION; A DRIVING MECHANISM FOR COMBUSTION INSTABILITY IN ROCKET ENGINES.

Abstract

The mixing and burning of gas/air jets in the presence of mechanical vibration of the injector was studied. Initial photographic Schlierer and spectroscopic observations of a H2/air and coal gas/air flame vibration conditions have been carried out. The vibration obviously enhances the rate of mixing and higher mean flame temperatures result. A closed solution was obtained for the case of a vibrated gas jet mixing with its surroundings, in the near-field (potential core) region. Generally speaking, the theory predicted that the vibration, treated as a source of vorticity, would raise the mean axial component of velocity at any point inside the mixing region. This was verified by a hot-wire anemometer investigation. Furthermore, it was established that the vibration drives the vortex shedding mechanism in the flow from an orifice. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1965
Accession Number
AD0628920

Entities

People

  • David Cochrane
  • L. Crane
  • P. D. Mccormack

Organizations

  • Trinity College Dublin

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Anemometers
  • Coal Gases
  • Combustion
  • Flow
  • Gases
  • Hot Wire
  • Hot Wire Anemometers
  • Near Field
  • Rocket Engines
  • Vibration
  • Vortex Shedding

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Internal Combustion Engine (ICE) Technology.
  • Structural Dynamics.