The HB concept (english)

Posted on May 15 2016

[powr-file-embed id=fb1f9a0a_1463505883983]

The HB Concept
Since day one, the Makani team worked really hard on offering the best fin collection on the market
with the widest range of weed fins. We are now introducing a new concept to the windsurfing fin world,
the hb concept. The idea is not new since it has been effective on whales flippers for many years but we
have been able to apply it on a windsurfing fin in a concept that
really works. Let’s briefly see how the idea works in nature,
how it has been translated
in science and
especially how it will
change your riding.

As you can see on the image above the humpback whales front flippers have tubercles on the leading
edge of their fins. Nature’s evolution is no hazard as Darwin discovered many years ago and these
tubercles have a function. They help these massive mammals to catch their prey by drastically enhancing
their manoeuvrability. Specifically, humpback whales use their flippers to achieve tight circles
while rounding up and eating their prey. So if these tubercles are so effective on whales we figured they
could also work on windsurfing fins The Makani humpback whale file was now open !

We gathered all the information we could find on these protuberances and contacted University teacher
Frank Fish Ph.d who worked on the idea. We realized that the scientific results were promising for the
hydrodynamics of wind sports. Many scientists like Frank have worked on the project for a good number
of years and some industrial applications such as wind mills
have already applied the idea with great success. The foils with
the leading edges protuberances did not stall in the same manner
giving a gradual stall rather then a drastic one one on flat leading
edges. They even had greater drag to lift coefficient. The conclusions
showed that the tubercles reduce drag, they delay stall and
give a higher angle of attack. Let’s not expand too much here and
see how we applied the idea on windsurfing fins.

Windsurfing fins
The challenge for us was to translate all the new datas and
project it into an actual fin design that would work. We felt that
starting with a single wave fin would be best so we could really
feel the influence of the protuberances on the leading edge. The
enhanced manoeuvrability would also be directly felt on actual
wave riding. We created a 3D generic model with key input parameters
on the sinusoidal leading edge that let us generate precise and
comparable prototypes to optimize the one that would end up in production.
The distribution of the thickness relative to the bumps frequency was a
key factor also in order to get the right flow behaviour with these leading edges
protuberances. Finally we selected a foil that would also match the results expected so
the HB concept fin would be efficient.
The tests have been clear and we now have a single wave
fin that gives the following advantages:
-Better upwind angle
-Better upwind speed
-Better grip in the turns
-Radical turn angles
-Drastically reduced spin outs
-Easier to recuperate after spin outs
The only negative feedbacks we found was all the questions
we got on the beach before going riding. We will
keep working on the concept and making it even better
and expanding it to other fins ... We have more prototypes
on the way !! Dealer, shaper, customer inquiries are welcome
as well !

Pin It


Leave a comment

All blog comments are checked prior to publishing

Recent Posts