MECHANISM OF VENTILATION INCEPTION ON SURFACE PIERCING FOILS

Either separation or cavitation is a necessary but not sufficient condition for ventilation inception, and the surface 'seal' must be ruptured in some way to admit air. Three modes of rupture have been observed: at the nose, at the trailing edge, and through the tip vortex. Nose ventilation is associated with the vortex in a separation bubble, and tail ventilation arises from the instability of surface perturbations and can be predicted empirically. Tip vortex ventilation is not likely on prototype craft. Waves increase the likelihood of ventilation and in open sea conditions a reduction of some 4 degrees in inception angle is predicted. Conventional fences suppress nose ventilation only.

• Corporate Authors:

  Institution of Mechanical Engineers

  1 Birdcage Walk
  London SW1H 9JJ,   England 
• Authors:
  • Swales, P D
  • WRIGHT, A J
  • McGregor, R C
  • Rothblum, R
• Publication Date: 1974-2

Media Info

• Features: References;
• Pagination: p. 18-24
• Serial:
  • Journal of Mechanical Engineering Science
  • Volume: 16
  • Issue Number: 1
  • Publisher: Mechanical Engineering Publications Limited

Subject/Index Terms

• TRT Terms: Hydrofoil boats; Hydrofoils; Ventilation systems
• Uncontrolled Terms: Separation
• Old TRIS Terms: Cavitating hydrofoils; Hydrofoil craft; Surface piercing hydrofoils; Ventilated hydrofoils
• Subject Areas: Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00057638
• Record Type: Publication
• Source Agency: Engineering Index
• Files: TRIS
• Created Date: Oct 5 1974 12:00AM