Low-Dimensional Dynamical Characteristics of Shock Wave /Turbulent Boundary Layer Interaction in Conical Flows

Abstract

Shock wave / boundary layer interaction is studied in a large area ratio axisymmetric nozzle comprising a design exit Mach number of 5.58. Shock motion unsteadiness is captured by way of the dynamic wall pressure and is evaluated during overexpanded operations of the nozzle up to a nozzle pressure ratio of 65. Stationary SWBLI is considered whereby the nozzle is operated at a nozzle pressure ratio of 28.7 such that the internal flow structure is in a restricted-shock separated state; the annular separation shock resides within a fixed intermittent region of the flow. Conditional averages of the wall pressure fluctuations show how the motion of the incipient separation shock is out of phase with pressure fluctuations measured in the separated region downstream of the shock; pressure decreases when the shock moves downstream and vice versa. This is indicative of a long intermittent region, in terms of the boundary layer thickness, as the observed phenomena can be explained by translating the static wall pressure profile along with the shock motion. Non-stationary SWBLI is also considered by increasing the nozzle pressure ratio over time (transient start-up). Under these conditions, the shock pattern is shown to vary in strength and structure as it sweeps through the nozzle.

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Document Details

Document Type
Technical Report
Publication Date
Dec 16, 2014
Accession Number
ADA613848

Entities

People

  • Charles E. Tinney

Organizations

  • University of Texas at Austin

Tags

Communities of Interest

  • Energy and Power Technologies
  • Materials and Manufacturing Processes
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Boundary Layer Flow
  • Computational Fluid Dynamics
  • Energy Bands
  • Fluid Flow
  • Frequency
  • Frequency Bands
  • Geometry
  • Hydrodynamics
  • Mach Number
  • Pressure Gradients
  • Pressure Measurement
  • Shock Waves
  • Simulations
  • Three Dimensional
  • Turbulent Boundary Layer
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Combustion Dynamics and Shock Wave Physics.
  • Combustion and Flow Dynamics.
  • Fluid Dynamics.