Hmmm... Might this work on the back of a car..?

[Logic]

https://www.youtube.com/watch?v=dLlJRujBWos

I'm thinking this might make for 'shorter tails' (but still how effective?) behind cars.
ie: tails at angles that are normally 'stalled' causing turbulent air.
And are at a shorter, more manageable length.

I like the 'fully automated', zero actuation energy, of them.
I 'd want to try spring loading them a little. (adjustable) They stay 'fully automated', but you have a 'trim tab' so to speak. Like the birds do..? I think so?

Lift to opposed sides cancels... so that looks like a smaller wake to me..?
Those springed 'trim tabs' should give you 'rudder control'...
Which has a torque component down the 'centre' of the vehicle.. That's 'lean'. in the wrong direction if you're thinking aircraft controls. (and 2 wheelers)
Inverting the 'rudder'? That tries to straighten you when you want to turn, but will ameliorate tail-happiness at speed.
Rudder in front of rear tire contact patch?

Hmmm... More lift... Is there a forward/backward component to that force, 'pushing/sucking' on the wing?
He said: "...pressure damp... prevents high pressure...from..." behind the wing, moving forward..!
Those look like small 'sails' to me..?

Interesting non the less

[aerohead]

Each feather on a bird is attached at feather follicles, which contain nerve endings, leading to the brain.
As a bird 'fledges', it's brain 'learns' how to morph its wings and tail, to accomplish it's flight dynamics ( like learning to crawl, walk, and run ).
--------------------------------------------------------------------------------------
Birds are 'most aerodynamic ' ( lowest drag ) during 'bounding flight', or' 'stooping,' where the feet and feathers are held as close as can be to the body, which then takes on the form of a 'streamline body of revolution'. A 'bomb'. Perrigrine Falcon at 244-mph ( 392-km/h ).
--------------------------------------------------------------------------------------
Automobiles would experience no benefit with the inclusion of 'feathers.' And their danger to cyclists and pedestrians would never allow them to make it through the certification process.
--------------------------------------------------------------------------------------
Aft-body length requirements for lowest drag are rooted in the adverse pressure gradient / flow separation relationship. No cheating possible.

[Logic]

No one?
That's a video to save you reading:

Distributed feather-inspired flow control mitigates stall and
expands flight envelope
https://www.bamlab.princeton.edu/_fi...fd70b218cf.pdf

The paper does have lots of pictures based on self actuating spanwise flaps on aircraft wings. (Tested)
(Can people still read and comprehend..?
Do people consider research worth reading?
Would they consider it worth reading if it was posted by someone else..?? )

[kach22i]

Originally Posted by Logic

Hmmm... Might this work on the back of a car..?

In the video they stated similar stall benefits no matter the position, even on aft locations of the wing.

The simplified model flaps that were of a clear material looked to be rapidly ripping away in a turbulent dance. I have been told this was bad, at least as it applied to the tonneau cover on my pickup truck.

I know what happens to flags over time, the ends fray, and same thing happens to the bottom of hovercraft skirts. On hovercraft the frantic pressure gradients may create an acoustic signature heard by fish - at least that's my theory based on an event I experienced plus some reading done years later.

I recently went to a funeral ceremony at the Great lakes National Cemetery for a departed Vietnam veteran friend. For a moment I thought I had a flat tire until I realized the sound was from all the American flags on a windy day.

Sound is energy, and this probably means an inefficient waste of some kind depending on the example (flag, hovercraft skirt, flexible wing flap....).

I did a quick search for "flexible wickerbill aerodynamics" thinking somebody has looked into this, but found nothing related to this thread's twist on the topic.

In short: I think you are flapping in the wind.

EDIT:

I'm starting to read the PDF, and regarding the oscillations creating vortexes this topic does indeed seem to be related to the Gurney Flap Spoiler or so-called Wickerbill.

So I'll just warn ya, Aerohead is all about "attachment", and probably regards vortex creation as wasted energy (in general).

I'm less set in my ways and say give it a try, the Cybertruck managed to get vortexes to work in their favor, right?

https://damogranlabs.com/2019/12/tes...-aerodynamics/