The meaning of circulation
Circulation is one of the most misunderstood terms in sailing. Yet, circulation is essential to understand lift and why sails, wingsails, keels, rudde…
Aerodynamics
The Reynolds number
The Reynolds number is the ratio of inertia forces to viscous forces involved in the flow. Reynolds understood that while inertia forces were dominant…
Understanding the boundary layer
In 1904, Ludwig Prandtl introduced an approach to understanding and analyzing flows around bodies that produced a massive breakthrough: the boundary l…
Bernoulli’s principle
The physical significance of Bernoulli's equation is what is known as Bernoulli's principle. It states that when the velocity of a fluid increases, th…
Flows in sailing
Sailing boats interact with flows of two very different fluids: air and water. Moreover, sailing boats are able to make their way through the water su…
Sails sets: Mainsail + Spinnaker forces and coefficients (calculation)
Calculation template How does it work? See also: Sails sets: Mainsail + Flying Headsail (calculation). Sails sets: Mainsail + Spinnaker (calculation). Mainsail aerodynamic coefficients (calculation).…
Sails sets: Mainsail + Flying Headsail forces and coefficients (calculation)
Calculation template How does it work? See also: Sails sets: Mainsail + Flying Headsail (calculation). Sails sets: Mainsail + Spinnaker (calculation). Mainsail aerodynamic coefficients (calculation).…
Sails sets: Mainsail + Headsail forces and coefficients (calculation)
Calculation template How does it work? See also: Sails sets: Mainsail + Flying Headsail (calculation). Sails sets: Mainsail + Spinnaker (calculation). Mainsail aerodynamic coefficients (calculation).…
Sails sets: Mainsail + Spinnaker (calculation)
Calculation template How does it work? Following the ORC VPP methodology, this template calculation combines the individual sail’s characteristics of a user-defined mainsail and a…
Sails sets: Mainsail + Flying Headsail (calculation)
Calculation template How does it work? Following the ORC VPP methodology, this template calculation combines the individual sail’s characteristics of a user-defined mainsail and a…
Sails sets: Mainsail + Headsail (calculation)
Calculation template How does it work? Following the ORC VPP methodology, this template calculation combines the individual sail’s characteristics of a user-defined mainsail and a…
Spinnakers aerodynamic coefficients (calculation)
Spinnakers are sails set forward of the mast where the measurement between the half luff point and the half leech point (SHW) is equal or greater than…
Headsails “Set Flying” aerodynamic coefficients (calculation)
A headsail is a sail set forward of the mast. Headsails may be set on the forestay or set flying, i.e., with no sail edge attached to the forestay. Wi…
Headsail aerodynamic coefficients (calculation)
A headsail is a sail set forward of the mast, or of the foremast mast if there is more than one mast, where the measurement between the half luff poin…
Mainsail aerodynamic coefficients (calculation)
A mainsail is a sail with the luff attached to the mainmast. The mainmast is the only mast in a una rig, sloop rig, or cutter rig, the fore mast in a …