AIR LIQUEFACTION BOUNDARIES EXPERIMENTALLY DETERMINED FOR THE BALLISTIC RESEARCH LABORATORIES' SUPERSONIC AND HYPERSONIC WIND TUNNELS

Abstract

The boundaries for the onset of air liquefaction were experimentally determined. These boundaries indicate the regions where the liquefaction of air constituents has an effect on the flow properties in the test section. The boundaries were determined by making static and total head pressure measurements (with varying temperature) throughout the appropriate Mach and Reynolds number ranges of both the supersonic and hypersonic wind tunnels. The results show that air liquefaction occurs near the theoretical boundary (Clausius-Clapeyron) for Mach numbers 4.75 and 5.00 with little, if any, supersaturation. However, as the Mach number increases to 6.0, 7.5 and 9.2, there is an increase in the amount of supersaturation before liquefaction occurs, and at a given Mach number, the difference between the experimental and theoretical temperature at the onset of liquefaction is about the same at all pressure levels tested. These results may allow a relaxation of our stagnation temperature requirements by an amount which would be of considerable operational significance at M = 9.2.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1967
Accession Number
AD0656445

Entities

People

  • Maurice A. Sylvester

Organizations

  • Ballistic Research Laboratory

Tags

DTIC Thesaurus Topics

  • Air
  • Boundaries
  • Boundary Layer
  • Flow
  • Free Stream
  • Hypersonic Wind Tunnels
  • Instrumentation
  • Mach Number
  • Measurement
  • Pressure Measurement
  • Reynolds Number
  • Saturation
  • Stagnation Pressure
  • Stagnation Temperature
  • Static Pressure
  • Test Equipment
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Combustion science or combustion engineering.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flow