Experiments on a 3-D Flapping and Pitching Mechanical Model

The motivation for this paper is to focus on the better understanding of
flapping wing flight, including flapping flight involving high pitching amplitudes. The
investigation will be primarily experimental. The experiment will utilize a mechanical
flapping and pitching wind tunnel model, which is modeled on large migrating birds. The
3-D rectangular wings are forced to flap and pitch sinusoidally in a low speed wind tunnel.
The unsteady aerodynamic forces generated are measured using a three-component force
balance. The main objective of this work is to investigate the effect that varying the
oscillation parameters has on the aerodynamic forces acting on the 3-D wing undergoing
flapping and pitching. The parameters in question are reduced frequency, flapping ampli-
tude and pitching amplitude. Comparisons are made with aerodynamic force predictions
obtained from unsteady vortex lattice calculations.