Plants, cables, clothes, bridges, plane wings and living organisms are various examples of objects that can change their shape when immersed in a strong enough flow. Changing shape can be undesired and lead to destruction: typical examples are wing flutters or vortex-induced vibrations. But changing shape is also a way to adapt to the flow and reduce the loading: trees resist much higher winds than if they were rigid. The heart contracts with blood pressure. And plants motion underwater can improve mixing.
At UNFoLD, we investigate experimentally how soft objects dynamically deform in a fluid flow and how the flow adapts in return.
The motion of flags in the wind is a typical example of closed coupling with the flow. We reproduce the flapping of flags in wind tunnel experiments where we reveal the flow features at play.
