Thank you patzefran, yes the angular momentum has to be conserved. When you stop generating lift this is fulfilled by the stop-vortex. Btw. there...
I shall make a last attempt to answer your question in a serious way. The potential flow theory is not "my" model, although I have used it,...
Nice simulations indeed. I am surprised that the reduction in wind-speed was only 3% at 45° true wind-angle. I would have expected some 20%...
What you see in Prandtl's movie is the downwash generated by the lift of the airfoil and how this downwash together with the fluid behind and in...
Nice visualization, but I think this classical visualization by Ludwig Prandtl shows the downwash and development of start- and stop-vorticies at...
Defining "lift" as the force perpendicular to the apparent wind-direction and "drag" as the force in the direction of the apparent wind is very...
Although the America's cup has not always been sailed in the fastest boats, it has always been sailed in boats that are far too big and expensive...
David, maybe Sailor Al is as familiar with vector analysis and concepts like irrotational flow-fields as you are. But I think also sailors, that...
If you want to get a better understanding of aerodynamic lift I recommend that you forget Violas's theory. I have watched it twice now, without...
My cat, Skilla just made a precision jump with a perfect point-landing on my shoulder. So I asked her what the function for her variable moment of...
Thanks for informing me CT249. I was thinking about yachts like Reliance, that sailed the Americas cup some 110 or 120 years ago. And I am very...
If you want a safe victory for the boat, that can stay on the foils, I recommend a zero-hull boat, that can not go anywhere after a touch-down. If...
Sure, the Vampire was sailing a few years before the the AC-75. And the advantages of this configuration are quite obvious. You are welcome to...
Maybe the box I suggested is too big. I just took the size from the AC-75 class we were discussing then. There may also be more clever ways to...
I can rather imagine a major tidying of the current class. There are elements in the AC-75 class, that are improvements over previous AC-classes,...
ETNZ won the America's Cup today. Both the defender and challenger demonstrated exceptional skill when sailing these not-so-easy-to-sail AC-75...
The AC-75 rigs are fairly aerodynamically clean, so it is reasonable to assume that they give the air, that flows past the sails, a change in...
It is difficult to find good names. But necessary. Most of my sailboats have lacked names. That's probably the reason I have not been as...
As I tried to tell in my previous comment, the downwash and tip-vortex, from a boat sailing 4 times the windspeed with the kind of load you have...
I was going to start a new thread on this subject after viewing the AC-races, and now you have already done that farjoe, what a coincidence! What...
