Michlet over estimates the total resistance

Discussion in 'Software' started by Andrea Kursetgjerde, May 16, 2017.

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  1. Andrea Kursetgjerde
    Joined: May 2017
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    Andrea Kursetgjerde New Member

    Hi

    Im trying to optimize a trimaran hull, which I later will verify against CFD. I already have som estimations on what the total resistance should be without any changes. From Michlet i get almost the 2x as much. Also, If i which off/on the slender body setting, nothing happens?

    Help please

    - Andrea
     
  2. patrik111
    Joined: Sep 2003
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    patrik111 Junior Member

    Have you possibly done your base caser CFD using a symmetry plane and therefore only see the results for half a hull?
     
  3. Andrea Kursetgjerde
    Joined: May 2017
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    Andrea Kursetgjerde New Member

    I have used symmetry plane, but I have included this in my calculations. My main hull have a very complex geometry, I have found that this may have caused some problems, any experience with this?
     
  4. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Being estimates...how do you know if this is correct? You need a confirmed baseline datum that is correct and verifiable by several sources, otherwise, you will be chasing your own tail!
     
  5. TANSL
    Joined: Sep 2011
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    TANSL Senior Member

    In my humble opinion, all power calculations (and many other calculations of naval architecture) are estimates. So, in my opinion, do not worry about your tail. :)
     

  6. CNair
    Joined: Feb 2017
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    CNair New Member

    How do the results of Michel integral based Michlet compare with results using panel based programs using say Rankine source distribution based on say Havelock/Newman green functions? I find Michlet's Wave Resistance prediction about 20-30% lower when compared with model test based predictions for an existing trimaran.
     
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