A cylinder in a flow produces a series of alternating vortices known as a von Karman vortex street. Changing the flow speed and rotating the cylinder both allow researchers to Keep reading
Tag: wake
Swimming in Line
When swimming in open waters, it pays to keep your ducks (or your goslings!) in a row. A recent study examined the waves generated behind adult water fowl and found Keep reading
Flexible Filament Reduces Drag
Most shapes aren’t streamlined for fluid flow. We call these bulky, often boxy shapes, bluff bodies. Above, we see two examples of a bluff body, a flat plate, in a Keep reading
Trails from a Delta Wing
Rhodamine (red) and fluorescein (green) dyes highlight the complex flows around a delta wing. To visualize the flow, researchers painted the apex of the delta wing with rhodamine, which gets drawn into Keep reading
Asymmetric Wakes
When a ship moves through water, it leaves a distinctive V-shaped wake behind it. In the nineteenth century, Lord Kelvin made some of the earliest theoretical studies of this phenomenon, calculating that Keep reading
Entraining Bubbles
If you stand on a bridge and watch the current flow past pylons below, you’ll see disturbances marking the wakes. Dragging a rod – or an oar – at a high Keep reading
Reshaping the Wake to Decrease Drag
When it comes to the aerodynamics of cars, there’s only so much streamlining one can do. In the end, most cars have a certain boxy-ness as a matter of practicality; Keep reading
Powdery Trails
Because air and water are colorless and transparent, we cannot see most of the flows around us – but they’re always there. In a recent series, photographer Jess Bell has Keep reading
Dinosaurs, Propellers, and Hiding Objects
The latest FYFD/JFM video is out, and it’s all about the interactions between structures and flows! We learn about plesiosaur-inspired underwater robots, how turbulence affects air-water interfaces, and how adding Keep reading
Swirls of Color
These beautiful swirls show the wake downstream of a thin plate. Here water is flowing from left to right and dye introduced on the plate (upstream and unseen in the Keep reading