Accession Number:

ADA499246

Title:

Influence of Structural Flexibility on Flapping Wing Propulsion

Descriptive Note:

Doctoral thesis

Corporate Author:

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

Personal Author(s):

Report Date:

2009-06-01

Pagination or Media Count:

180.0

Abstract:

The influence of structural deformations on the aerodynamic response of a flapping wing configuration was examined using Navier-Stokes based simulation. Two deformation modes, torsion and bending, were considered for an elastic axis along the leading edge of the wing. Both deformation modes influence the velocity and acceleration profile of the wing surface, altering the unsteady aerodynamic phenomena produced by the dynamic wing motion. The spanwise feathering rotation, or torsional response, alters the motion of the wing near the wing root. This variation in the acceleration profile influences the non-circulatory aerodynamic response and the local wake structures produced near the wing root during pronation and supination. Increased lifting forces and enhanced aerodynamic efficiencies were observed for a moderate increase in torsional exibility. Peak bending deformations near the wing tip also occur during pronation and supination, altering the velocity and acceleration profiles of the wing as the circulatory aerodynamic phenomena undergo a transition as the wing changes direction of motion. Because of the timing of the bending deformations, small tip deformations may have a significant influence on overall aerodynamic performance.

Subject Categories:

  • Lighter-than-air Aircraft
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE