Accession Number:

ADA214244

Title:

Flow Visualization of the effect of Pitch Rate on the Vortex Development on the Scale Model of a F-18 Fighter Aircraft

Descriptive Note:

Master's thesis

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s):

Report Date:

1989-06-01

Pagination or Media Count:

144.0

Abstract:

Experiments were performed in a water tunnel to visualize the vortex bursting phenomenon on a 148th scale model of the F-18 fighter aircraft. Photographs were taken to investigate the effect of pitch rate and yawing on bursting locations of vortices shed from the forebody and the strake during simple pitch up and simple pitch down maneuvers in an angle of attack range up to 50 degrees. It was found that the vortex burst point moves upstream with increasing pitch rate. At the same pitch rate, vortex bursting was usually found to occur earlier for the pitch-down than for the pitch-up maneuver. Aircraft yawing generated significant vortex asymmetries due to earlier vortex bursting on the windward side thus leading to undesireable side forces and yawing moments. Keywords Fluid dynamics Aerodynamics. KT

Subject Categories:

  • Aerodynamics
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE