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Paper Title: Comparison Between Freewheeling and Locked Sailboat Propeller Drag Using a Computational Fluid Dynamics Approach



R E Spall, Utah State University, USA


Computational fluid dynamics calculations were performed to predict the drag of locked and freewheeling 2- and 3-blade, 12 inch diameter, 6 and 10 inch constant pitch sailboat propellers.  Drag levels and coefficients for both freewheeling and locked configurations are presented for flow velocities ranging from 1 m/s to 4 m/s.  Results indicate that the drag for the freewheeling configurations were in all cases below those for the locked configurations at equivalent flow velocities.  However, the relative magnitude of the decrease was found to be strongly dependent on the blade design.


Transactions RINA, Vol 156, Part B2, International Journal of Small Craft Technology, Jul-Dec 2014 

DOI Number

DOI No: 10.3940/rina.ijsct.2014.b2.160

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