Sail Loading on Rig, Rig Loading on Vessel

[brian eiland]

The 2009 version of the Mirabaud LX, Thomas Jundt’s foiler has a new hull that favours speed and stability by light wind. Its mast has also been reinforced in order to improve the upwind sailing angle, as well as the reactivity of the boat. Finally, the sensors used to trim the foiler’s flaps have been improved, allowing a better precision whilst sailing. Introduced in 2008 as “the boat with no hull”, the Mirabaud LX has recently proved that this wording could be translated into reality by sailing on its hydrofoils with no buoyancy at all. Thomas Jundt and his team have accomplished this challenge and validated a different and creative way to consider the sport of sailing.

...and check out this YouTube Presentation
http://www.youtube.com/watch?v=Lx6K1PzqnG0

[MikeJohns]

Foilers have been around for decades of course and carbon fibre composites are allowing the concept to move into lighter air operation.



The times have moved on since this thread started and German.. Lloyds publish some reasonably well considered guidelines which I have attached here.

Any rig desin these days particulalry if a novel design, should be using FEA. All you need is beam elements and tension (cable) elements for the rig evaluation. Then a column buckling assesment when you find your compressions to refine the mast section.

The approach is to assess the sail forces for smooth water at the sail attachment points, these are applied to a non pre-tensioned beam and cable FEA model. A FOS accounts for pre-tension and dynamic loads. This approach seems to be working.

We use Strand7 for this and it is very easy to use.

[brian eiland]

DSM Dyneema, producer of Dyneema®, the world’s strongest fiber™, is recruiting the globe for 40 ‘Skippers’. They can test running-rigging made with Dyneema® fiber and share their experiences through social media.

If you are selected to join the 2011 Dyneema® Experience Team, we will re-rig your boat completely free of charge with ropes made with Dyneema®. All we ask of you is that you test and experience rigging with Dyneema® and share this with us, your friends, family and other sailors worldwide,

http://www.dyneemaexperience.com/?utm_source=scuttlebutt&utm_medium=mailing&utm_content=Join%2Bnow&utm_campaign=Dyneema%2BExperience%2BTeam

[petereng]

Hi Brian, Vectran is quite a bit stronger than Dyneema so I'm not sure where the claim of strongest fibre comes from? Published data is Dynema 2432MPa and Vectran 3000MPa ultimate tensile strength. But Dyneema (HM-PE) is a bit lighter. Density of Dynex is 980kg/m3 but Vectran is 1400kg/m3. But Vectran like PBO is a naturally highly oriented polymer and needs no heat treeatment or stretch processing to get to HM. But HM-PE is acheived by heating and stretching to orient the fibres. This process is not 100% efficient so there are non optimal fibres in the construction. Plus as the polymers have been stretched they like to return to their original condition. This is called relaxation. Commonly called creep but creep is different. VE/PBO being naturally oriented can be loaded at 50%+ UTS higher loads continuously with no relaxation. However HM-PE can only be loaded at 30% of its UTS continuously otherwise it can relax and loss its tension. So for standing rigging its a toss up. I like Vectran as I can tie knots in it, splice it and not worry about UV degradation of relaxation.
Regards Peter S