AN INVESTIGATION OF THE COMPRESSIBLE LAMINAR WAKE BEHIND A LONG SLENDER CYLINDER.

Abstract

A theoretical and experimental investigation of the compressible laminar wake behind a long slender cylinder has been made. The theoretical investigation has led to approximate solutions which are valid within the entire wake region extending from the rear stagnation point. Solutions for two-dimensional and axially symmetric flows are obtained from the momentum and energy equations which are linearized on the basis of centerline properties. A sample calculation for the profiles in the near wake was made. An experiment to produce a thick laminar compressible wake behind a long thin circular cylinder was devised. The free stream Mach number and Reynolds number were 4.02 and 2300/inch, respectively. The electron beam-fluorescence technique was used to obtain the density and rotational temperature profiles for stations extending from a half diameter to 42 diameters downstream from the base of the cylinder. Impact pressures were also obtained at these stations. Measurements in the separated region indicated the existence of large gradients in static pressure. Comparison of theory and experiment for a station located 4 diameters downstream of the base showed good agreement. Further calculations by computer are required, however, before the theory can be assessed completely. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1966
Accession Number
AD0802263

Entities

People

  • Robert H. C. Au

Organizations

  • University of California, Berkeley

Tags

DTIC Thesaurus Topics

  • Axisymmetric Flow
  • Diameters
  • Electron Beams
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Free Stream
  • Mach Number
  • Measurement
  • Reynolds Number
  • Stagnation Point
  • Static Pressure
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.

Technology Areas

  • Directed Energy
  • Microelectronics