Oyster 100’ sailplan study

1. Oyster 100’ sailplan study Study conducted using SA-Evolution, a SMAR-Azure technology Boat: Oyster 100’ Sail: blade jib & mainsail Date: November 24th 2010 Responsible: Sabrina Malpede Contents 1. Aerodynamic Analysis 2. Aerodynamic Optimization

2. 1. Aerodynamic Analysis INPUT DATA • Design shapes provided by Dolphin Sails • True wind speed 12 kn • Target TWA 43.3° • Target BS 8.93 kn • Heeling angle 10° • Sheeting angle 12.3° jib / 2° main RESULTS • Thrust 11690 N • Side force 48020 N • Heeling moment 894.7 kNm • Thrust Coefficient 0.40 • Side Coefficient 1.64 • Thrust / Side Ratio 0.24 Notes • Sails are flying at appropriate angle of attack • Foresail is developing higher forward thrust Pressure distribution

3. 2. Aerodynamic Optimization Results INPUT DATA • Target sailing course at 12 TWS (see previous slide) • Sheeting and heeling angles have been kept fixed Jib design shape • Twist and maximum camber has been evenly reduced throughout the foresail Mainsail design shape • Twist has been slightly evenly increased, while camber has not been changed RESULTS • Thrust 12620 N +8.0% • Side force 46770 N - 2.6% • Heeling moment 865.6 kNm - 3.3% • Thrust Coefficient 0.43 +8.0% • Side Coefficient 1.59 - 2.6% • Thrust / Side Ratio 0.27 +13% Conclusions • Even if the thrust is increasing considerably, the side force and the heeling moment are decreasing instead, allowing a much higher overall efficiency of the sailplan