Mixing Effects of Pylon-Aided Fuel Injection Located Upstream of a Flameholding Cavity in Supersonic Flow (Postprint)

Abstract

An investigation into the non-reacting flow associated with the pylon-aided gaseous fuel injection upstream of a flame holding cavity is described. Characteristics of penetration and mixing were measured in a Mach 2 freestream environment. The downstream combustion cavity had an LID of 4.7 and an aft ramp angle of 22.5 degrees. A circular injection port was placed upstream of the cavity, and a series of three pylons (medium, tall, wide geometries) were in turn fitted just upstream of the port to examine changes in mixing and penetration of the fuel into the core airflow. The main goals of this experiment were to characterize the mixing ability of injected fuel with the core flow as it propagated downstream of the pylon and to analyze the effects, if any, of this mixing strategy on cavity flow and overall efficiency compared to a no pylon case. Visual measurements were obtained using Planar Laser-Induced Fluorescence (PLIF), and Mie scattering techniques. Of the three pylon geometries tested, the wide pylon (1.6 jet diameters wide, 4 diameters high) provided a 135% increase in penetration. All pylons lifted the fuel from the injection wall in the farfield (a flashback related issue), and all pylons demonstrated distinctive mixing characteristics when compared to the flat reference, although quantifying experiments on this subject are recommended.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2005
Accession Number
ADA463272

Entities

People

  • Campbell D. Carter
  • Daniel R. Montes
  • Kuang-yu Hsu
  • Mark R. Gruber
  • Paul I. King

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Boundary Layer
  • Combustion
  • Flow
  • Fluids
  • Fluorescence
  • Fuel Injection
  • Geometry
  • Laser Induced Fluorescence
  • Lasers
  • Measurement
  • Mie Scattering
  • Research Facilities
  • Scattering
  • Supersonic Flow
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Internal Combustion Engine (ICE) Technology.
  • Optical Physics and Photonics.

Technology Areas

  • Directed Energy
  • Hypersonics