INITIAL STUDY OF THE EFFECT OF CRYOSURFACE GEOMETRY ON CRYOPUMPING

Abstract

An experimental study of cryogenic pumping using several cryosurfaces in the pressure ranges of .0001 and .001 mm Hg is presented. At these pressures, where the mean free path of the condensable gas is on the order of the cryosurface dimensions, it is shown that the pumping rate is no longer a constant as it is in free-molecular flow, but increases through what is termed the transition range and presumably approaches a higher constant value in the continuum flow regime. Flow in the gas kinetic, gas dynamic, and transition regimes is discussed. Experimental results are presented showing the effects on cryopumping of the addition of fins or ribs to a cryosurface, and the effect of pumping with parallel cryosurfaces at different separations.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1962
Accession Number
AD0274355

Entities

People

  • E.s. Wang
  • J.a. Collins Jr
  • J.d. Haygood

Organizations

  • Arnold Engineering Development Complex

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Boundary Layer
  • Computational Fluid Dynamics
  • Cryopumping
  • Experimental Data
  • Flow Rate
  • Fluid Dynamics
  • Fluid Mechanics
  • Government Procurement
  • Kinetic Theory
  • Knudsen Number
  • Mean Free Path
  • Partial Pressure
  • Pumping
  • Pumps
  • Temperature Gradients
  • Transitions

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.