THE WAKE OF A CATALYTIC FLAT PLATE IN A LOW DENSITY DISSOCIATED GAS FLOW.

Abstract

Experimental measurements of the concentration profiles in the wake of a catalytic flat plate are reported. Tests were conducted in a glow discharge tube at pressures of .1 to 1 Torr, using oxygen as the working gas and centerline velocities on the order of 1000 cm/sec. The oxygen was weakly dissociated (about 5%) by a radio frequency driven induction coil, upstream of the test section. The flow then passed a silver coated flat plate, which catalytically recombined the oxygen in its vicinity. The resulting concentration wake was then surveyed using a constant temperature hot catalytic thermistor probe. A concentration analog to the classical laminar momentum solution for the wake of a flat plate at zero incidence was proposed with the diffusivity playing an analogous role to the kinematic viscosity. Tests conducted at plate Knudsen numbers of .110 and .330 produced good correlation with the classical continuum wake theory, even though these flows were conducted in a regime where continuum theory loses its validity. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 15, 1970
Accession Number
AD0711291

Entities

People

  • Daniel L. Pike

Organizations

  • United States Naval Academy

Tags

DTIC Thesaurus Topics

  • Diffusivity
  • Discharge Tubes
  • Flow
  • Frequency
  • Gas Flow
  • Glow Discharges
  • Knudsen Number
  • Low Density
  • Measurement
  • Momentum
  • Physical Properties
  • Radio Frequency
  • Thermistors
  • Viscosity

Fields of Study

  • Physics

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Fluid Mechanics and Fluid Dynamics.
  • Plasma Physics.