EVALUATION OF POROUS MATERIALS AS MOLECULAR LEAKS,

Abstract

From the experimental results obtained, adsorption effectively makes Knudsen's flow theory inadequate for predicting the conductance of a molecular leak. This necessitates calibrating the molecular leak for each gas or vapor that will be used. Of the four types of leaks tested, porous glass and porous stainless steel offer the best possibilities for use as molecular leaks at relatively high pressures (100-760) TORR). A leak fabricated from porous glass exhibits molecular flow up to atmospheric pressure. For a conductance of 0.00001 liters/sec for N2, the over-all length of the leak is approximately 8 in. with an OD of 15/32 in. The leak is easily contaminated and has a great affinity for water vapor and other vapors. It is difficult to mount and easily broken.

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1964
Accession Number
AD0602922

Entities

People

  • A. J. Mathews

Organizations

  • Arnold Engineering Development Complex

Tags

DTIC Thesaurus Topics

  • Adsorption
  • Barometric Pressure
  • Ceramic Materials
  • Glass
  • High Pressure
  • Materials
  • Porous Materials
  • Reinforcing Materials
  • Sizing Compounds
  • Stainless Steel
  • Steel
  • Test And Evaluation
  • Vapors
  • Water Vapor

Readers

  • Aerospace Test and Evaluation
  • Combustion and Flow Dynamics.
  • Systems Analysis and Design