Self-Excited Roll Oscillations of Non-Slender Wings

Abstract

The main objective of this research is to understand the free-to-roll aerodynamics and self-excited roll oscillations of low aspect ratio wings. Generic thin, flat-plate wing planforms for unmanned air vehicles and micro air vehicles were considered. Slender and nonslender delta wings with sweep angles between 40-deg and 70-deg, cropped delta wings, rectangular wings with aspect ratios of AR = 2 and 4, Zimmerman, and elliptical wings were investigated. Measurements of roll history, flow visualization, and PIV measurements were conducted in the free-to-roll experiments in a wind tunnel. Nonzero trim roll angles and self-induced roll oscillations were observed for most of the wings. Leading-edge vortices, tip vortices and separation bubbles play an important role in the free-to-roll aerodynamics. Hysteresis and time lag effects are behind the observed roll oscillations. The results may be useful in improving the maneuverability and gust response of unmanned air vehicles.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 2010
Accession Number
ADA537734

Entities

People

  • Ismet Gursul
  • Surya Surampudi

Organizations

  • University of Bath

Tags

Communities of Interest

  • Air Platforms
  • Autonomy

DTIC Thesaurus Topics

  • Aerodynamics
  • Aircrafts
  • Airframes
  • Aspect Ratio
  • Boundary Layer
  • Delta Wings
  • Fixed Wing Aircraft
  • Flow Visualization
  • Fluid Dynamics
  • Fluid Mechanics
  • Leading Edges
  • Measurement
  • Micro Air Vehicles
  • Shape
  • Turbulent Mixing
  • Unmanned Aerial Vehicles
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Control Systems Engineering.

Technology Areas

  • Autonomy