Sections for Proa Boards and Rudders

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Paper (HTML)
Proa 1-Series
Proa 2-Series
Proa 3-Series
NACA Sections

Paper (PDF)
Appendix A (PDF)
Appendix B (PDF)
Appendix C (PDF)
Appendix D (PDF)

Hydrofoil section designs for proa sailboats which reverse direction in a shunt when changing tacks are presented.  These sections have fore-aft symmetry with blunt leading and trailing edges.  The design rationale for three families of sections is discussed.  XFOIL computed data are provided for all sections at Reynolds numbers of 500,000 to 2,000,000, cambers ranging from 0 to 2%, and thickness ranging from 8% to 12%

The Proa 1-series were based on circular biconvex thickness distributions with rounded edges.  This series exhibited excessive drag and flow separation.  The Proa 2- and 3-series were designed using an inverse method.  A boundary layer trip was found to be necessary for the Proa 2 series.  The Proa 3 series achieved performance comparable to NACA sections without a boundary layer trip. 

Complete coordinates and data plots can be found in the appendices.


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