Doyle CFD recently finished a study comparing predictions made with our RANS CFD based VPP system to on the water performance data logged on a J70. We have been supplying yacht designers with aerodynamic and hydrodynamic RANS CFD force data for the past six years. Two years ago we started to develop our own VPP program to work directly with our CFD data. This study is our first attempt at making a one-to-one comparison between sailing states predicted in the VPP analysis and to real world. To do this it is important to accurately capture the 4 hydrodynamic state variables; boat speed, heel, yaw and rudder angle, as well as the sail flying shapes and the apparent wind conditions.
The initial comparison looks promising. Boats speed compared to predictions are shown below.