ON MAGNETOHYDRODYNAMICS OF ROTATING FLUIDS,

Abstract

The influence of rather general electromagnetic forces acting upon steady rotating motions of conducting viscous incompressible fluids over a rotating disk is investigated by means of adjustable local boundary layer approximations of first order. Numerical results for the most important motions of von Karman and Bodewadt are displayed and discussed in full detail. The hypothesis of small variations of the imposed magnetic field assumed in other investigations is found to be justified provided the corresponding Hartmann number and magnetic Reynolds number are of sufficiently small magnitude. Considerable distortions of the rotating motions result from strong electromagnetic forces. When the strength of the imposed electromagnetic forces is increased, the secondary motions may change their stagnation character to wake character, and vice versa. In addition to critical Reynolds numbers critical Hartmann numbers and magnetic Reynolds numbers are shown to exist beyond which no simple boundary-layer-type motions are possible. The interpretation of the spacial instabilities of wake-type flows as a separation phenomenon is supported by the 'tea-cup' experiment photographed. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1965
Accession Number
AD0627919

Entities

People

  • Ernst W. Schwiderski
  • Hans J. Lugt

Organizations

  • Naval Surface Warfare Center Dahlgren Division

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Distortion
  • Fluid Mechanics
  • Instability
  • Layers
  • Magnetic Fields
  • Magnetohydrodynamics
  • Personality
  • Reynolds Number

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Fluid Mechanics and Fluid Dynamics.