Secondary Flows in Jets and Their Effects on Fluidic Components,

Abstract

On the basis of physical and mathematical arguments it is shown that the flow of a fluid from a nozzle of rectangular cross section contains an axial component of vorticity, called secondary flow, that is directly related to the Reynolds number and inversely related to the radius of curvature of the nozzle. The results of tests on open channels, water tunnels, and air models are given, verifying the presence of these secondary flows. As a consequence of the propagation of this vorticity downstream with the jet, the attachment of a three-dimensional jet is found to be considerably different from the often assumed two-dimensional case. Known secondary flows were introduced through the power nozzle into two typical fluidic units, and the operating characteristics were found to change considerably but predictably, based on the knowledge of the sense of rotation and cellular structure of the imposed secondary flow. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1970
Accession Number
AD0719232

Entities

People

  • R. Pierce Trask Ii
  • Tadeusz M. Drzewiecki

Organizations

  • Harry Diamond Laboratories

Tags

DTIC Thesaurus Topics

  • Attachment
  • Cellular Structures
  • Curvature
  • Flow
  • Geometric Forms
  • Geometry
  • Lines (Geometry)
  • Mathematics
  • Reynolds Number
  • Rotation
  • Secondary Flow
  • Three Dimensional
  • Tunnels
  • Two Dimensional
  • Water Tunnels

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Fluid Dynamics.