Accession Number:

ADA390885

Title:

Simulation and Analysis of Wing Rock Physics for a Generic Fighter Model with Three Degrees-of-Freedom

Descriptive Note:

Doctoral dissertation Sep 1996-Aug 2000

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT

Personal Author(s):

Report Date:

2000-07-01

Pagination or Media Count:

115.0

Abstract:

Modern fighter designs have been associated with lateral self-excited oscillations own as Wing Rock. Simulations of wing rock by flow visualization utilities have been encouraged to develop a complete understanding of the fluid mechanism that drives fle motion as well as for prediction purposes. Previous windiwater tunnel simulations have been limited to a single degree-ofifreedom DoF in roll. In this study, for the first time, wing rock is computationally simulated in three DoF roll, sideslip, and vertical motion to study the effect of adding file sideslip and vertical motion. The results are for a generic fighter model consisting of a fore-body, a cropped delta wing, and a vertical fin. The effect of including the vertical fin is also studied. The interaction of aerodynamics and rigid-body dynamics during a single DoF wing rock for the wing-body configuration has been studied via snap shots of a cross-plane stagnation pressure distribution and tracing ile instantaneous locations of vortex burst for an entire cycle of wing rock. The effect of adding the sideslip and vertical motion DoF to the simulations of the wing-body configuration was found to delay file onset and to reduce the amplitude of wing rock by about 50 with surprisingly no change in frequency. The wing rock simulation in three DoF was repeated for file full generic fighter model with fle fin included. The aerodynamic effect of fle fin was found to significantly delay the vortex burst on the upper surface of the wing. The net effect of the fin was found to augment the damping of the oscillations with significant increase in frequency.

Subject Categories:

  • Aerodynamics
  • Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE