3 ms·
> active drag reduction What the heck is active drag reduction?
by Simon_ORourke 2y ago
> active drag reduction
What the heck is active drag reduction?
- Someone 2y agoDecreasing drag through active flow control. https://en.wikipedia.org/wiki/Flow_control_(fluid)#Active_control https://en.wikipedia.org/wiki/Flow_control_(fluid)#Active_co...: “Passive devices by definition require no energy. Passive techniques include turbulators or roughness elements geometric shaping, the use of vortex generators, and the placement of longitudinal grooves or riblets on airfoil surfaces. Active control requires actuators that require energy and may operate in a time-dependent manner. Active flow control includes steady or unsteady suction or blowing, the use of synthetic jets, valves and plasma actuators. Actuation may be pre-determined (open-loop control) or be dependent on monitoring sensors (closed-loop control).” An example: continuously changing wing surface (https://www.gauss-centre.eu/results/computational-and-scientific-engineering/active-friction-drag-reduction-in-turbulent-boundary-layer-flow https://www.gauss-centre.eu/results/computational-and-scient...) I don’t know either something like this has been built or flown.