Launch of largest sailing yacht ever built

Discussion in 'Boat Design' started by Remmlinger, Sep 21, 2015.

  1. daiquiri
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    daiquiri Engineering and Design

    Very interesting observation. I didn't notice that exhaust stack in front of the mast at the first glance.
    Carbon fibre alone is sufficiently resistant to high temperatures, losing just some 10% of mechanical strength at 250 °C and 20% at 350 °C. The weak point is the resin. A carbon-epoxy uni, for example can lose up to 50% of strength at approx. 250 °C. A carbon-polyimide unidirectional strength drops by just 10% at 350 °C. We do not know which resin was used in this application, but you do have a very good point there.
     
  2. Clarkey
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    Clarkey Senior Member

    Yes, my thought was that there may be sufficient heat to soften the matrix.

    The video linked to in post #102 shows a significant heat plume from the exhaust at around the 3:05 minute mark and what looks like local discolouration at the base of the damaged mast.

    How easy or difficult might it be to resolve this issue? (if, indeed, it is the issue)
     
  3. daiquiri
    Joined: May 2004
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    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    The mast is there and it cannot be changed. The position of the exhaust piping probably cannot be changed. IMO, they will have to cool the exhaust somehow to the ambient temp. or so, before discharging it into the atmosphere. Or divert the plume sideways, far from the mast.
     
  4. W9GFO
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    W9GFO Senior Member

    I'm not convinced there is structural damage. At the 26 second mark you can see what appear to be some cracks - but they are not, they are lines or wires that are taped to the mast. Possible thermocouples?

    The panels strapped onto it look to be ad hoc heat shields.

    Around the 2:47 mark you can see that the mast is perfectly in line with the other two. I would not think that likely if there had been buckling.

    My guess is that they caught the heat issue before it caused a failure, but they will have to verify that it has not been weakened.
     
  5. Manie B
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    Manie B Senior Member

    My goodness interesting video,
    that is a lot of hot air to deal with
    phew - design / engineering mistake of note
    going to be very interesting to see what happens with this lot
     

  6. Clarkey
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    Clarkey Senior Member

    I think you are correct. Still, an interesting issue to deal with.
     
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