Investigation of shock boundary layer interactions to unravel the physics of unstart in axisymmetric inlets

Abstract

The vision of the project is to bring about an unprecedented understanding of the mechanisms that result in the inflated propensity of the axisymmetric inlets to unstart. Given the preponderance of the shock boundary layer interactions (SBLI) in inlets and their critical role towards unstart in planar geometries, the objective of the present effort is to unravel how the shock interactions with axisymmetric inlet/isolator boundary layers can inflate their unstart propensity. The objective was approached from three specific angles: 1. Unravel the response of the started inlet with unseparated boundary layers to back pressure fluctuations and the length scales over which a given shock leg would respond to a downstream pressure fluctuation within the isolator. 2. Make detailed investigations of the unique phenomena and mechanisms that occur with shock interactions with axisymmetric inlet/isolator geometries, which causes the inflated propensity to unstart. 3. Investigate the changes in the SBLI within the inlet/isolator duct caused by circumferential variations in the incoming boundary layer, which both provide insights into situations that occur in angle of attack flight as well as opportunity to delay the onset of inlet unstart.

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Document Details

Document Type
Technical Report
Publication Date
Apr 14, 2020
Accession Number
AD1104325

Entities

People

  • Venkateswaran Narayanaswamy

Organizations

  • North Carolina State University

Tags

Communities of Interest

  • Air Platforms
  • C4I
  • Energy and Power Technologies
  • Materials and Manufacturing Processes
  • Weapons Technologies

DTIC Thesaurus Topics

  • Acoustic Propagation
  • Acoustic Waves
  • Air Force Research Laboratories
  • Back Pressure
  • Boundary Layer
  • Convection
  • Frequency Bands
  • Geometry
  • Pressure Distribution
  • Pressure Gradients
  • Pressure Measurement
  • Repetition Rate
  • Scattering
  • Supersonic Combustion Ramjet Engines
  • Three Dimensional
  • Turbulent Mixing
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Systems Analysis and Design