KINETIC THEORY OF THE AERODYNAMIC DRAG OF A SLOWLY ROTATING SPHERE.

Abstract

The drag of a sphere rotating slowly inside a concentric stationary sphere is analyzed for a range of values of the mean free path in the gas filling the space between the spheres. Knudsen iteration is used to predict the drag for high values of the Knudsen number, based on the ratio used to represent the gas phase collisions. Based on this result and that appropriate for slip flows (low Knudsen number) two interpolation formulas are suggested to predict the drag for arbitrary Knudsen number. The predictions from these formulas agree well with available experimental data. A solution of the problem, using the moment method proposed by Lees, Leads to a simple algebraic expression for the drag which is not in such good agreement with the data. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1967
Accession Number
AD0810351

Entities

People

  • D. Roger Willis

Organizations

  • University of California, Berkeley

Tags

DTIC Thesaurus Topics

  • Aerodynamic Drag
  • Agreements
  • Collisions
  • Drag
  • Experimental Data
  • Flow
  • Interpolation
  • Iterations
  • Kinetic Theory
  • Knudsen Number
  • Mean Free Path
  • Slip Flow
  • Stationary

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.

Technology Areas

  • Space
  • Space - Orbital Debris