Several problems of engineering interest have strong interactions between the fluid flow around surfaces/bodies, and the motions/deformations of the solid surfaces/bodies. Examples of such problems range from compressor blade flutter of aircraft engines to the gentle flapping of leaves in the wind. In these problems, the strong interactions between the fluid and the solid surfaces can result in rich and interesting dynamics both within the fluid and in the deformations or motions of the solid surfaces. We are exploring a range of such Fluid-Structure Interaction problems in the lab. These include the flapping of flexible foils for the generation of efficient thrust in “robotic fishes”, the unsteady shock induced flutter of compressor blades, stall flutter of single blades or airfoils and the flow through flexible valves. One of the focus areas in FSI within the lab has been on studying the effects of surface flexibility in a few flow configurations motivated by biological systems, whose surfaces (tissues/membranes) are inherently flexible.
In this connection, we have studied
- the effects of vortex-pair/vortex-ring generation from a flexible exit, motivated by the propulsive action of some aquatic creatures such as the jelly-fish, and heart valves that are composed of flexible membranes.
- the forces and wake of an oscillating flexible airfoil motivated by the undulating motions of a “flexible” fish tail to generates propulsive thrust.
- the effect of a flexible splitter plate in the wake of cylinder for reducing drag and to suppress noise and vibrations.