Transient Heat Transfer Effects from a Flapping Wing

Lind, R.J., Abedian, B.
Department of Mechanical Engineering Tufts University, Medford, Massachusetts

This presentation is a numerical study of fluid flow around a two-dimensional rigid flapping plate and its effects on the resultant transient heat transfer effects on the solid interface.

In this study, a flat inflexible thin plate surrounded by air undergoes sinusoidal angular motion from one end while the other end is kept stationary, simulating a flapping motion. The two-dimensional incompressible Navier-Stokes equations along with the energy equation are solved to determine the velocity and temperature fields around the plate. Results have been obtained for the case of a flapping plate in quiet air and with an axial free stream air velocity U.

In the FEMLAB calculations, the flapping plate is simulated by assigning the resulting oscillatory axial and lateral velocities to the solid interfaces, with the axial velocity having a frequency twice the lateral velocity.

It is shown that, in some ranges of dimensionless parameters, the tip vortices on either side are spinning alternatively clockwise and counterclockwise. The effect of this binary vortex formation at the tip on the unsteady heat transfer on the plate is investigated.