Research is underway by Philip Rolla, founder of Rolla Propellers, into the development of improved propeller blade geometry for surface piercing propellers. Rolla Propellers is now part of the Twin Disc group which supplies both submerged propellers and the surface piercing designs in which Mr Rolla has specialised. His blade development improves the distribution of pressure and control to wetted and ventilated regions of the blade via a positive step between the one-fifth and four-fifths chord length of the blade. This creates a high pressure peak or zone in what is now a low pressure zone on either the blade face or back, or both, to create speed-controllable wetted and ventilated regions.
展开▼
