USE OF HYDROGEN BUBBLES FOR QUANTITATIVE DETERMINATION OF TIME DEPENDENT VELOCITY FIELDS IN LOW SPEED WATER FLOWS,

Abstract

Improved flow visualization methods based on the hydorogen bubble technique are described. Use of 'combinedstreak markers' allows quantitative measurement of the instantaneous velocity field in a plane as a function of time in low speed water flows. Adaptation to a great variety of situations using different probe techniques is possible. Disturbance to the flow is very small. Adequate accuracy is obtainable. The method offers the advantage of simultaneous visual images of the flow structure and quantitative measurement of velocity over a finite region. It also allows some types of measurements not previously possible. Limitations of the method include its restriction to low speed water flows and the observation of fluctuations only at low frequencies. Practical difficulties occur due to probe frangibility and problems of uniform bubble production. Part I describes the underlying concepts, summarizes the history of the method and describes operating experience to date at Educational Services, Incorporated and Stanford University. Part II is a detailed analysis of the uncertainties in velocity measurements using combined-time-streak markers formed by hydrogen bubbles. (Author)

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1964
Accession Number
AD0602795

Entities

People

  • A. Littell
  • F. A. Schraub
  • J. Henry
  • P. W. Runstadler Jr.
  • Stephen Jay Kline

Organizations

  • Stanford University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Accuracy
  • Flow
  • Flow Visualization
  • Frequency
  • Hydrogen
  • Measurement
  • Observation
  • Production
  • Stratified Fluids
  • Uncertainty
  • Universities
  • Visualizations
  • Water Flow

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Systems Analysis and Design
  • Underwater engineering and Marine Technology.