Hi Luc,

The styling I have chosen has been influenced by both the Visionarry and the Norwegian proa. The software can produce a wide range of shapes however.  The sharp seam on the Norwegian proa is no problem – same with chines – easier to produce than a constant radius that requires fairing into another radius or stem.

I didn’t feel that the Steiner ww hull styling suited a fuller bodied windward hull.  The sharp edge compliments the fine lines of that hull but didn’t seem to mesh with the one I was working on.

Concerning the KSS compounding in the bow section: I am not committed to fully developing the compounded shape without resorting to foam carving.  Developing the shape in the software assists in design aesthetics.  The build choice will be determined by a combination of engineering requirements and build simplicity. It’s worth noting from the KSS panels on the web page that the compounding in the bow is not likely to be that tricky – the darts are not particularly large.

Concerning degrees of freedom in hull shape design: this was my principal reason for developing the software.  The other packages I’ve looked at restricted my design brief.  Software that relies on NURBS surfaces is fine until heavily compounded regions are added longitudinally to slightly compounded ones; then it can become very fiddly to fair a hull.  If you can draw a hull design on paper but can’t successfully draw it in 3d with software then find something that will.  I have used my software to generate NURBS surfaces for the finite element modelling I’m now working on.  It presented problems though:  in areas of the hull in which the hull surface was too far from normal to the hull sections faint ripples in the surface appeared – even when the hull curvature lines were used as guides.

I’m leaning toward round bilge, high prismatic and a little rocker for the following reasons:

1.       Reduced wetted surface for light wind performance.

2.       Aesthetics. A fair surface from stem to stem.

3.       To generate an exacting test of the software I’m developing.

The first two can arguably be traded against the reduced build time of the rockerless hull, but would limit the scope for a full test of the software.

Thanks for expressing your thoughts re the software.  Time will tell concerning how it develops. I haven’t promoted it anywhere yet (other than here) as my time is restricted.  With PhD studies on the backburner while I get the this boat built and a lifestyle change happening, I don’t know when I’ll find time to put a graphical interface into the software.  At the moment I build sets of parameters for different hull configurations and file input the small amount of section detail required for the program to run.

David