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Serviola_ en la ingeniería naval debe haber algunos conceptos claros, no inmutables desde luego, pero si mas claros
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Lo que es muy mutable es la mar, donde dos olas seguidas pueden se parecidas, pero nunca iguales.
Tienes un barco que marcha estupendamente en el Atlantico Norte, pon un pesquero escoces de arenque rojo tipo Fifie, con su recta proa vertical, y de que llega al Cantabrico donde a a esa ola se suma la mar de leva atlantica y ya no va tan bien...hace falta otra cosa delante, como ilustran los pesqueros de Santoña.
Se gastaron fortunas inmensas el siglo pasado en la busqueda del diseño de velero mas rapido en traer un cargamento de the desde la China a Boston y
W. Griffith invento la famosa Clipper bow que garantizaba una marcha sin frenazos en portantes, sin meter la proa si el monzon arreciaba y queria inundar el puente y estropear la valiosa mercancia.
Compromisos...compromisos.
Seaworthiness
"One of the reasons is the full bow design. If you look at the bow of any good seaworthy boat, you will see that it is shaped like the pointed end of a football. If you lay a football on its side in a pool of water and heel it over, there is no change to its underwater shape. And this is what occurs to the bow of the boat, which is spoon shaped and, like a spoon when it is heeled over, the shape remains the same. This is not true, however, for the clipper bow that you have seen on clipper ships. This is a concave forward quarter section that looks beautiful as it enters the water, slicing its way through the waves. But somewhere there you have to pay the price. Somewhere you still have to push the mass of the boat through the water. Now you can start entering it very finely but you still have to get back to the mass. If you start off concave then you just get full a little farther back. Clipper ships were well known for their downwind performance, but you never saw them really beating to windward for when they were beating to windward they were laid over on their sides. When a clipper ship is laid over on its side, you’ve changed its attitude. You don’t have that football bow. You have a differently shaped bow. It is concave, and when a wave smashes into that concave bow the tendency is not only to slam the boat but to slow its forward momentum. This might not be as critical on a large sailing ship as it would be on a sixteen-foot sailboat that lacks the mass to push itself through the seas. So even though the clipper bow was a beautiful sight on the old sailing ships, it doesn’t work on every boat.
When beating into the wind, the full bow of the traditional bow design is such that as the boat heels, the waterline actually increases, and therefore the boat sails faster at that angle," They told me.
como curiosidad un ultimo (feisimo) diseño de proa que dicen ser el mas rapido con mar muy dura
http://www.youtube.com/watch?v=UaaVeBkeJZQ
http://www.youtube.com/watch?v=3zZ_tzndh1U
