Velocity Profile Measurements in the Knudsen Layer for the Kramers Problem.
Abstract
An experimental study of the Knudsen layer is reported. The use of an effusive source to generated a local approximation to the Kramers problem over a flat surface is described. Velocity profiles are measured with a free molecule orifice technique which required no assumptions as to the form of the molecular velocity distribution function. Data are obtained in the Knudsen layer for polished aluminum, oil and Crocus cloth surfaces. The normalized slip coefficients for these surfaces are in agreement with theoretical predictions for the BGK and pseudo-Maxwellian molecular models, found by different techniques, if the tangential momentum accommodation coefficients are 0.96, 0.90 and 1.07 for the respective surfaces. Within the Knudsen layer, the velocity profile is compared with the linearized BGK model equation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1974
- Accession Number
- ADA013835
Entities
People
- J. F. Wendt
- J. J. Smolderen
- M. A. Reynolds
Organizations
- von Kármán Institute for Fluid Dynamics