On Fri, 22 Oct 2004 17:06:07 GMT, igavioli wrote:
I am planning to mount a bow thruster on a 41' Sailboat and i wonder if
someone
knows the influence of the tunnel opening at the bow. Namely how much
the created
turbolence will affect the performance of the sailboat.
In the Vetus Web site, as small as possible tunnels (possibly more than
one) are suggested just to keep the resistance under way low;
unfortunately this very statement
makes me worry!
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It's difficult if not impossible to quantify the drag but it will
definitely be significant. Racing boats go to great lengths to either
plug up, or put mylar flaps over, through hull fittings that are far
smaller than a bow thruster aperature. The bow thruster aperature is
also in just about the worst possible place as it will disrupt
attached flow over the entire length of the hull. If you are serious
about sailing performance, I would not install a thruster.