A fixed cylinder will shed alternating vortices in its wake, but one allowed to oscillate forward and backward in the flow instead sheds simultaneous vortices. The shape of the wake Keep reading
Tag: wakes
An Oasis Among Dunes
The Saudi Arabian oasis of Jubbah sits in the bed of an ancient lake. It’s protected from the westerly winds that sculpt the surrounding dunes by the wind shadow of Keep reading
Sensing Obstacles Through Flow
Mosquitoes, bats, and even eels use non-visual means to sense their environments. For mosquitoes, part of their obstacle avoidance comes from the exquisite sensitivity of their antennae, which are able Keep reading
Dunes Avoid Collisions
The speed at which a dune migrates depends on its size; smaller dunes move faster than larger ones. That speed differential implies that small dunes should frequently collide into and Keep reading
The Microscopic Ocean
When you’re the size of plankton, water may as well be molasses. Viscosity rules at these scales, and swimming plankton leave distinctive wakes that are slow to dissipate. Fish that feed on plankton use Keep reading