Biomimicry

[r.oril]

My wife saw this information on the shape of a whales flipper. Question, would this work on a rudder and daggerboard?
http://www.nwf.org/News-and-Magazin...ls/Archives/2009/Mimicking-Mother-Nature.aspx

 

[kloudie1]

Pretty kool, but what a trash collector ! Every piece of string, weed, crab pot line, etc within 2 miles would get hung up on the ridges.. Probably OK if you have a swing keel that can be pulled up to clear it while under way.
All fun and games 'till someone puts an eye out on them bumps!

 

[DannyS]

I have a friend in our marina that modified his Freedom 20 by adding "tubercles" on the leading edge of his rudder and keel. He did this with golf balls that he cut in half and then epoxied and faired in place. He was convinced it worked. We sail on Lake Superior...no crab pots or weeds to worry about.
He's a little bit crazy though...in a good way.

 

[walt]

I think that particular whale feeds on small fast schools of fish and needs to turn quickly - ie, it needs the fins to generate very high lift without stalling. Past discussion on this (I believe) came to the conclusion that the structure on the fins was possibly more about not stalling under high lift conditions than good lift to drag. Not exactly what National Wildlife mag says..

I think we are generally more concerned about higher lift to drag ratio.

 

[caguy]

I think that particular whale feeds on small fast schools of fish and needs to turn quickly - ie, it needs the fins to generate very high lift without stalling. Past discussion on this (I believe) came to the conclusion that the structure on the fins was possibly more about not stalling under high lift conditions than good lift to drag. Not exactly what National Wildlife mag says..

I think we are generally more concerned about higher lift to drag ratio.

I would think that while it may not benefit the keel or dagger board it could make a difference on the rudder. It may reduce stall on a hard turn or increase steerability at lower speeds.

 

[sinnettc]

Could you test with a pool noodle?

I would think that while it may not benefit the keel or dagger board it could make a difference on the rudder. It may reduce stall on a hard turn or increase steerability at lower speeds.

It might be interesting to cut a pool noodle down and tape a few pieces to the front of the rudder to test that theory . . . it would require good tape and an unpainted rudder though.

 

[r.oril]

It might be interesting to cut a pool noodle down and tape a few pieces to the front of the rudder to test that theory . . . it would require good tape and an unpainted rudder though.

I have the original rudder for my Mac 26D that was replaced by a new Ida Rudder. I like your "noodle" idea.