A numerical method that is successfully applied in yacht design are the
genetic algorithms. The computer is used to improve a design in an
evolutionary process through many generations. I presented first
results
of
this method at the
Second High Performance Yacht
Design Conference
2006 in Auckland. The validity of the optimum depends heavily on
the accuracy of the predicted speed potential of the yacht. The speed
must be calculated from the geometries of hull and sails, where the
resistance of the hull can be predicted on the basis of the research at
the TU Delft. All influences on driving- and resistance-forces are
still not known though. Of great help were the towing tank test
data of a Dehler 33. They were thankfully supplied by the SVA
Potsdam. The status of my work as of 2012 is described
here.
Since the beginning of 2013 all test
results from the towing tank of
the
TU Delft are available on their web-site. This is a new
invaluable knowledge base. Based on this experimental data and an
additional boundary-layer calculation, I have developed a new correlation for the residual
resistance. A prerequisite
for this task is explained
here, the theoretical background and the results of the regression analysis can be found in this
report. The database was increased by adding the towing tank results for the
Delft-372 model. UliTank is a computer program that incorporates all the newest findings. In 2015 the
Sailing Yacht Research Foundation
published
on their website towing tank results that were conducted in
2003. I used these results to increase the database of the regression
analysis for the new version UliTank_3.2.This new version
computes the resistance with appandages in the heeled
attitude and with leeway. UliTank_3.2 can be
downloaded
here.
The
next step is the modelling of the sail forces. These are based on the
aerodynamic characteristics of the 2D sail sections. A first report can
be downloaded
here.