I just come to some new idea,Vibration.How it may effect fin or even foil? I am guessing the spontaneous vibration because poor material or loose bolts may be harmful to efficiency and speed.But good vibration !! may be good news !! Take for example foil wind. That is airfoils shape. If we could deliver external energy to foil, is should work like a flippers.
Flippers could propel fish faster then any windsurfer ever goes.
If future design of the complete rig - sail, board, foil or fin.
could generate vibration the are transferred specially to the foil- be design- it should
in principle provide additional force, making us faster !! I could imagine experimental test rig to check the concept. We could mount our foil on the hinge at front edge , and attach vibrating tool to the rear end.Obviously test in the water tank at first.They changing speed RPM and distance movement in mm we could see clearly water been thrown like a boat propeller or better.the same principle shold apply to our windsurfing fin.
Vibrating like fish flipper by external energy should actually accelerate our board even faster .
I can imagine future rig designs that generator vibrations utilizing wind power that is then transferred to the fin or foil to provide additional acceleration/ thrust.What do you think? will it works ?

Unless you are introducing the vibration artificialy (ie motorized) then the vibration will be caused by occilating movement of fin or foil which will create fatigue in the unit an premature failure.

Realistically it wouldn't be all that flash for stability either.

I've had fins which "sing" before and found them dragy

Betteridge's Law.

Are you referring to a marine equivalent of Aeroelastic Flutter Macro ?

The Beach Boys knew about vibration , and they thought it was good .

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jn1 said..
Are you referring to a marine equivalent of Aeroelastic Flutter Macro ?

No, in general I can envision powered vibration to provide additional energy. Lets call them active.Although spontaneous , passive vibration, designed materials on molecular level may also appear usefull.For example to shake off turbulence behind object.Maybe water also doesn't stick to vibrating surface. For sure doesn't stick to Ultrasonic frequency which create micro bubbles. Take for example fin. I wonder what percentage of forces components that provide drag/ resistance. say surface friction, force to cut water in front, sucking by turbulence behind fin ...etcI have been thinking also about serrated rear edge of the fin,. I need to try one day on one of my older fins to make multille cuts on read edge. How to effect turbulence and drag.

Vibrations. Hint something is off. Brain fart moments. More than once. Our launch off or rental on Maui has a bit of wind shadow. Sometimes you need to pump, do the hula to get into clean wind. One day got too excited. Really nice wind and waves at 1100. Pump like crazy. Just wasn't really moving. Then hit the clean air. Vibrations...Dragging a sea anchor feeling. What the h... Friends were lined up onshore all laughing. Thought it was from my excessive gyrations to get going. Something wasn't right. Off the board to discover the fin cover still on.