Helium Bubble Survey of a Parachute Opening Flowfield

Abstract

A velocity survey of the flow field surrounding an 18 inch nominal diameter flat circular parachute model was made using the helium bubble technique. Due to asymmetrical model behavior arising from optical limitations, only two points in the filling cycle were examined. The point at which the canopy first reaches full open (instant at which inflation is complete) and at a time late in the cycle when steady state flow conditions are reached. Bubble streaks were photographed by two synchronized, orthogonally mounted still cameras, and the particle velocities were calculated using the measured lengths of the images and the camera exposure times. Although the canopy geometries at the two points considered were quite similar, their surrounding flow fields were not.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1973
Accession Number
AD0761098

Entities

People

  • Paul C. Klimas

Organizations

  • United States Army Soldier Systems Center

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Cameras
  • Diameters
  • Flow
  • Flow Fields
  • Flow Visualization
  • Fluid Flow
  • Geometry
  • Measurement
  • Ordnance Laboratories
  • Parachutes
  • Particles
  • Photographs
  • Photography
  • Radial Velocity
  • Steady State
  • United States
  • United States Naval Academy

Readers

  • Aerial Delivery - Logistics and Supply Chain Management.
  • Combustion and Flow Dynamics.
  • Geodesy