scaling applied to multihulls

Discussion in 'Multihulls' started by peterchech, Jul 29, 2011.

  1. peterchech
    Joined: Aug 2010
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    Location: new jersey

    peterchech Senior Member

    I am not seriously considering scaling up any designs in the near future, but after reading many posts about the scaling up of monohulls and the laws of "mechanical similitude" I got to wondering :D...

    general consensus seems to be that, for the most part, a monohull can be safely lengthened by up to 10% without negative consequences, often gaining in stability. This can be done by simply increasing distance between station molds. Does this apply equally to a cat or tri?

    general consensus also seems to be that increasing the overall dimensions of a monohull shouldn't be done more than 2-3% if at all. Again, multihulls?
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    Whenever you change the overall dimensions by more than 10%, you need to re-engineer all the structure. That applies to multihulls too. For example, a 10' wave will be 100% of the length of a 10' hull but only 20% of a 50' hull. The stresses and handling are very different.
  3. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    The laws of mechanical similitude apply to kitchen chairs, office desks, mutli hulls and everything else alike.
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