Three-dimensional effects on the aerodynamic performance of flapping wings in tandem configuration

Abstract

A weakly coupled immersed boundary method and dynamic algorithm for the fluid-structure interaction of multibody systems, J. Comput. Phys., Under review.

Characterization of Aerodynamic Forces on Wings in Plunge Maneuvers

“…Hence, we have conjectured that the observed difference between experiments and simulations might be related to the interaction of the leading edge vortex with the wing tip vortices. According to previous studies [34,37], these interactions may cause a quicker dissipation of the leading edge vortex, or a change in its trajectory. Note that while wing tip vortices were present in the finite aspect ratio wings used in the experiments, they were not present in the spanwise-periodic wings used in the simulations.…”

“…Thus, the results shown in figure 9 support the conjecture offered in the first paragraph of section III.A; namely that towards the end of the deceleration phase the LEV shed during the acceleration phase approaches the upper surface of the wing, producing a suction peak that yields a positive contribution to . and TEV shed by finite aspect ratio wings dissipate much faster than those produced by airfoils or infinite aspect ratio wings due to the wake compression [34] and the vortex break-down caused by the non-linear interactions between LEV, TEV, and the wing tip vortices [37]. Also note that the Reynolds number is higher for the finite aspect ratio wings, which could also contribute to more unstable vortices and a quicker vortex break-down.…”

Fluid-structure interaction of multi-body systems: Methodology and applications

“…For further details on the immersed boundary method described above, the reader is referred to Uhlmann [12]. This algorithm has been implemented in a flow solver called TUCAN, which has been successfully used for the simulation of rigid-bodies with prescribed kinematics [40,41,42,43,44,45]. Likewise, the free motion of a single-rigid body immersed in a fluid has been also successfully simulated [46,47], using the coupling method presented in Uhlmann [12].…”

Three-Dimensional Effects on Plunging Airfoils at Low Reynolds Numbers

“…TUCAN has been successfully employed in flapping wing studies of infinite [14,24,25] and finite [26][27][28][29] aspect ratio wings.…”