Hydrofoil Cavitation Improvements with Elastically Coupled Composite Materials

Laminate construction technology is used to reduce the local angle of attack at the tip of an elliptic foil to delay the inception of tip vortex cavitation. As the angle of attack is increased on the foil, the increased lift causes the tip to flex in a direction that relieves the hydrodynamic loading in that region, resulting in delay of the inception of tip vortex cavitation. The global decrease in lift of the foil caused by unloading of the tip is very small, and cavitation is still delayed with respect to the same overall foil lift.