wrote in message
...
I would say that a keel which makes ZERO leeway is highly efficient...
super-efficient.... preternaturally efficient!


"Charles Momsen" wrote:
~A leeway angle of zero degrees means the flow comes head on at the keel.
Since keels are symettric, the net lift is zero and the drag is a
quantity
greater than zero. L/D = 0 in that case.


Oh, you're assuming that the keel is symmetric? You didn't say that at
first. You just said zero leeway angle.

Also the keel is on backwards.


Maybe the keel you're looking at has micropores connected to a pump
that induces a pressure differential accross the foil at zero AoA,
producing lift with no leeway.

That's highly ineffective. The pump should pump water onto the surface of
the keel through the micropores to eliminate the boundary condition that the
water velocity=0 relative to the keel. The lift will increase by a factor of
at least 6.




Maybe the keel you're looking at is a ballast strut and the leeway is
being eliminated by an asymmetric foil daggerboard or a toed-in
leeboard or a controllable twin foil, all of which are well proven
configurations and can produce zero leeway.

They produce zero leeway for the boat. I'm talking about relative direction
between the keel and the fluid as the leeway angle.





Maybe the boat is being towed to windward by a giant.

Or by midgets.



Did your physics prof introduce new conditions after the problem had
been stated and answers given? Mine didn't.

Neither did mine, but when someone was confused or didn't understand they
did offer to explain the problem more.

But he did encourage a
wide range of correct solutions rather than dogmatically insist on a
single prosiac answer.


That's great! Did any of the wide range of solutions involve adding new
information/parameters to the question? If not, could you explain how a
science problem can have 2 correct but different answers?

Did your physics professor ever teach the "law of parsimony"?