WAMIT Excitation Force Nondimensionalization

Discussion in 'Software' started by maltox, Oct 15, 2012.

  1. maltox
    Joined: Oct 2012
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    maltox New Member

    Does anyone know how WAMIT nondims the excitation force with water density when water density doesn't have to be specified for the Force Control File (using Alternative 1)? I'm guessing it is implied somehow but I'm having trouble figuring out how.

    This question may be out of the scope of this forum; is anyone aware of a solid WAMIT forum? I'm new to the software and have a few questions.
     
  2. CWTeebs
    Joined: Apr 2011
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    CWTeebs AnomalyGenerator

    Attached Files:

    Last edited: Oct 15, 2012
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  3. tava.amitava
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    tava.amitava New Member

    To add to the answer,

    non-dimensional force=Force/(rho*g*A*L^m)

    Here, A = 1,
    L = non dimensianalizing length used in GDF file parameter ULEN
    rho is automatically defined by WAMIT based on the unit of gravitational acceleration "g" defined in GDF file.
     
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  4. Murdock86
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    Murdock86 Junior Member

    I think excitation forces refer the incoming wave forces (Froude Krylov) and scattering components.

    Empirical Haskind relations are one way to get them (IOPTN (2) in WAMIT's FRC file). Another way is to obtain the same through the diffraction potential as given in the screenshot you attached. IOPTN (3) is the FRC file option that needs to be used in that case.
     

  5. Murdock86
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    Murdock86 Junior Member

    To answer the OP's question, I agree with tava.amitava's answer.
     
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