Experimental Observations on an Unsteady, Normal Shock/Boundary Layer Interaction,

Abstract

An experiment is described in which a normal shock interacts with the natural turbulent wall boundary layer in a parallel sided duct at Mach 1.3 and 1.5. The shock wave is vibrated in symmetric fashion by a rotating cam mounted in the tunnel diffuser. The design of this experiment, particularly the efforts to obtain a pure forcing signal, is discussed. Shock motion analysis at reduced frequencies of order 0.2 to 2 and amplitude parameters of 2% to 20% (based on equivalent chord) is presented. Unsteady surface pressure measurements under the interaction have been made and demonstrate that there is negligible phase change between the shock motion and the surface pressures. It appears reasonable to utilise quasi-steady assumptions in the calculation of the surface pressures at the low frequency conditions tested.

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1987
Accession Number
ADP005510

Entities

People

  • J. A. Edwards
  • L. C. Squire

Organizations

  • University of Cambridge

Tags

DTIC Thesaurus Topics

  • Amplitude
  • Boundaries
  • Boundary Layer
  • Diffusers
  • Frequency
  • Frequency Shift
  • Layers
  • Measurement
  • Observation
  • Pressure Measurement
  • Shock
  • Shock Waves
  • Waves

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Fluid Mechanics and Fluid Dynamics.