Sail Flow Presentation

470 upwind in waves, downwind under spinnaker
470 upwind in waves, downwind under spinnaker

The first animation shows turbulence around the 470 pitching in waves upwind, the second is about sailing downwind under spinnaker, and the last part sohws trimming the spinnaker from running to reaching. (c) WB-Sails

470 turbulence in 13 kn of wind.
470 turbulence in 13 kn of wind.

Turbulence around 470 sails in 13 kn of true wind, with shrouds & rigging included. 45% of the total drive comes from the jib, even if it is only 30% of sail area. The drag of the rigging (shrouds, trapeze wire & spreaders) is 1% of the total drive, similar to the drag of the skipper. The skipper is...

Finn creating its apparent wind
Finn creating its apparent wind

Simulation video associated with the presentation "How the sailboat works" by Mikko Brummer at the Technology Days 2014 in Otaniemi, Finland. A Finn moving through the static (true-) wind field, creating its apparent wind. The wind field is only modified locally, and mostly in velocity, apart from ...

Turbulence around Star sails in waves
Turbulence around Star sails in waves

Turbulence around the sails of a Star sailing in waves in 12 kn of wind. When the bow is pitching up, the mast top is pitching back and the head of the mainsail is loaded. This results in flow separation & turbulence on the leeward side. Conversely, when the bow pitches down, the flow separates on ...

Star bear away-stall
Star bear away-stall

Vortcity shed behind the sails of a Star bearing away from close hauled. (c) WB-Sails

Interference between boats when sailing upwind
Interference between boats when sailing upwind

A collection of animations about Finn class boats interfering with each other when sailing upwind. You can read more online here https://issuu.com/finn-class/docs/finnfare-november-2018/12, or download as pdf here https://www.finnclass.org/images/stories/finnfare/Finnfare-November-2018.pdf (c) W...

Finn Free Pumping
Finn Free Pumping

Simulating sail forces when free pumping in the Olympic Finn-dinghy. Note: Tripling the sail force does not mean tripling the boat speed. All the simulations were done at a similar speed range, varying around 4 kn (the boat speed is not constant). In reality, with free pumping boatspeed will be hig...

Simulating Dragons on the run
Simulating Dragons on the run

Simulating Dragons on the run WB-Sails has used their Dragon model for studying interaction between boats on the race course. One boat overtaking another (blue spinnaker overtaking the red), is simulated in the computer. The two boats are sailing in a true wind field, moving to form their own appar...

470 upwind in waves, downwind under spinnaker
470 upwind in waves, downwind under spinnaker

The first animation shows turbulence around the 470 pitching in waves upwind, the second is about sailing downwind under spinnaker, and the last part sohws trimming the spinnaker from running to reaching. (c) WB-Sails