4 ms·
With the relative wind angle mostly being dead ahead because of the engines, this means that the vessel will effectively be sailing a close hauled course. When
by fourseventy 4y ago
With the relative wind angle mostly being dead ahead because of the engines, this means that the vessel will effectively be sailing a close hauled course. When sails are trimmed for this heading, most of the force generated by the sail is perpendicular to the direction of the vessel. In normal sailing vessels this perpendicular force is converted into forward velocity with a keel. Without a keel your sailing ship will just drift sideways when attempting to sail a close hauled course. I'm assuming that giant shipping container ships don't have a keel, so how will these sails generate effective forward velocity for the ship and not just drag the ship horizontally off course?
- jmoorebeek 4y agoWhile a container ship doesn't have a keel per-se, it does have about 200m of flat plate length sticking into the water. At small angles, that flat plate can actually have a decent lift to drag ratio. Historic sailing vessels also made do without a modern wing-keel, so our current plan is that the container ship can crab into the wind by less than a degree to produce all of the side force required to maintain a steady course.
- Rorando 4y agoYeah a classic keel is not needed for bigger vessels as long as GM is low enough. One big difference between sail ships and modern ones is the increased air draft which effects the lift to drag ratio. Looking at your answers so far, I assume you've considered this already.
- jmoorebeek 4y agoYes, I can't say that we have absolutely everything figured out so far, but we have a decently complete model. Windage, changes to draught, and GM are already factored into our models at the root level, and while we may need to still tweak things we aren't waiting to be surprised by their effects.