Cruising Sailors Forum Archive

Both of these 'theories' are WRONG

(Restored after inadvertently deleted)
Fluid dynamicists (aero and hydro) have long described that lift is generated by the action of fluid viscosity. They acknowledge that the 'flow' is a (vector flow) 'circulating' about the foil created/initiated by a generated 'vortex' at the trailing edge due to the fluid VISCOSITY --- is what causes the 'lift'. Simplistic Energy Method physics or Newtonian Physics (inviscid flow) will always result in whats known as D'Lamberts Paradox = "0" lift.

A brief paper written to explain the viscous effects causing lift: http://www.arvelgentry.com/techs/Origins_of_Lift.pdf This brief was written to explain the aerodynamic effects that generate LIFT in SAILS but can be derived for any fluid --- just change the VISCOSITY value.

What you learned about lift in USA high schools and almost all 'sailing books' is utter nonsense; and, has been so since the time time of the Wright Brothers.

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