Performance Prediction for Sailing Yachts - Calm Water

Read our notes on the application of CFD in high performace yacht design.

For large yacht design campaigns we run hundreds of sailing points for each design candidate, and as many candidates as the campaign time allows. The best design is found by comparing all candidates, for example the diagram on the left below shows drag over side force for many yachts at a given sailing condition. Each candidate is also compared against a reference design to understand the effects of specific design features. The center and right diagrams below compare load distribution and trim versus velocity for a given candidate.

Drag over side force for a series of yachts at given sailing condition

Longitudinal load distribution for a candidate hull and its reference hull

Trim of a yacht candidate compared to its reference at different speeds

We use advanced visualization techniques to understand performance differences between design features. We either analyze the flow ourselves, or provide the visualization files to our clients. We use the Ensight post processing suite, one of the best in the market, to generate 3D visualization files called 'scenarios'. These files can be viewed using free viewing software which allows users to rotate, zoom, pan, and switch on and off the different parts of the body or flow features, such as free surface, pressure, friction coefficient, stream lines, turbulence, separation, vorticity and so on.

3D 'scenario' file showing the wave deformation around a yacht

3D 'scenario' file showing pressure coefficient around the keel of a yacht

3D 'scenario' file showing stream lines around the appendages of a yacht