How important/beneficial is an assymetric hull?

 
skyl4rk
 
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skyl4rk
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04 January 2013 16:52
 

Is it worth the extra design and construction effort to build an assymetric hull?

 
Adam
 
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Adam
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04 January 2013 19:54
 

It’s worth it if you’re planning on going through shallows a lot. That’s the chief advantage, shallow draft. You don’t gain efficiency as a general rule, if not a hard and fast law. I answer somewhat vaguely because experts have said you’re better off having a highly efficient hull complimented by highly efficient foils, yet I’ve never seen proof that this is necessarily true.

 
Editor
 
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Editor
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04 January 2013 20:12
 

AFAIK, their has been no scientific study of the usefulness of an asymmetric hull. I’d vote for that study, over say, the chances of getting fat by eating Chicken McNuggets study.

 
 
Johannes
 
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Johannes
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11 January 2013 12:50
 

Based on my experience with my monoproa and bargeproa models I must say that there is a lot of potential advantages with asymmetry. A flat(ish) leeside will make the proa very directionally stable when sailing in large ocean swells or breaking waves. When the wind and/or waves push the vaka toward lee a flat leeside will resist any turning effect the wave has
Every aspect of a boat is a tradeof and positioned on a scale. Asymmetry will solv some problems and create new ones. I believe asymmetry is essential on a bluewater cruising proa.

Cheers
Johannes

 
 
Johannes
 
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Johannes
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14 January 2013 06:31
 

Kiribati dimple

Both the United States Navy and Jaques Cousteau carried out experiments on the form drag of fish and marine mammals. When towed (dead) at their known respective speeds, the from drag of their streamlined bodies was far greater than their musculature could possibly propel them.
I believe that we have been looking at the dynamics wrongly.
No fish dolphin, shark or seal is ever symmetrical when swimming at speed. They are always at any given moment either asymmetric one way, or the other. Whilst asymmetric at the extreme extent of flex the body is curved on one side and hollow on the other

Very interesting text about asymmetry.

Cheers
Johannes