Oscillations of Ventilated Cavities Expermental Aspects

Abstract

By injecting air in the low pressure regions of water flows, it is possible to obtain cavities similar to the attached cavities due to "true" cavitation. That ventilation is a current practice in the field of spillways for large concrete dams, especially in tropical zones. It is aimed to diminish the risks of erosion, as the speeds of the water flows ordinarily are very large: the stresses between concrete and water are diminished by the injected air, due to its compressibility which increases the characteristic time of contact and diminishes the forces for the same total impulse. Then the main problem is to calculate the ideal dimensions of the ducts by which atmospheric air is sucked up under the water flow (Chanson, 1999). Here our main concern is rather on the side of ventilated hydrofoils or, possibly, torpedoes.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 2001
Accession Number
ADP012073

Entities

People

  • J. M. Michel

Organizations

  • National Center for Scientific Research

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Compressors
  • Air Flow
  • Air Pressure
  • Barometric Pressure
  • Bubbles
  • Cavitation
  • Coefficients
  • Curvature
  • Flow
  • Flow Rate
  • Froude Number
  • Geometry
  • Pressure Gradients
  • Three Dimensional
  • Two Dimensional
  • Water Flow
  • Water Jets

Readers

  • Combustion and Flow Dynamics.
  • Marine Propulsion Engineering and Naval Architecture
  • Theoretical Analysis.