Traditional rudder design query

[CarlosK2]

we can play with producing only lateral force at the bow, so that the sum of the hull's lateral force plus the rudder's lateral force balances the sails' lateral force.

"deep bow and rudder" ( + without lateral Low pressure, Suction, at the Stern)

Yeah

I think it's a very difficult path to calculate or not worth the effort.

The best-solved case I know of is Matt Lyden's Paradox, which uses the Heel of the hull to transform the hull into a lifting fuselage/body

Lifting body - Wikipedia https://en.m.wikipedia.org/wiki/Lifting_body

 

[CarlosK2]

Paradox

Lateral Force = Heeled Hull (+ Leeway/Yaw) as Lifting Body + Rudder

And at the stern, the water exits straight, without curves that create low pressure, suction.

 

[CarlosK2]

Heeled Hull, symmetry Broken
+ Yaw/Leeway

Bow ------ Stern

H: High pressure
L: Low pressure

Huuuge Hull Yaw Moment
Total Lateral Force= 0

 

[gonzo]

I meant the leeway with respect to the centerline. When heeled, the immersed hull is rotated by a few degrees, plus some helm to balance the boat. This produces a sufficient angle of attack to go straight along the centerline. Not very important, just interesting.

krzys

That happens only when you are going straight downwind. Otherwise, there is always leeway.

 

[gonzo]

This layout is so uncommon, that little is known about its hydrodynamics in practice

Not really, ask anyone that fishes from one.

How much variation around these designs is possible? Nobody knows.

Look at the different versions of the type. The builders new how much variation.

The closest modern boats are beach cats, like Hobie 16 - also a relatively shallow hulls and deep rudders.

Not even close even by the furthest stretch of the imagination. Comparing a heavy monohull to a light catamaran is like comparing oranges to tires.