Wetted Surface Area?

Discussion in 'Boat Design' started by naupigos_gr, Feb 5, 2009.

  1. naupigos_gr
    Joined: Feb 2009
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    naupigos_gr Junior Member

    hello i am new member, my name is john.
    i study marine engineering and naval architecture in Technological Dept. of athens .
    i have a problem with a designing exercise. i am looking for " wetted surface area" in this model of that tanker which is in surface compartments (1:150)
    if anyone knows that problem please help me!! thanks in advance
    :confused:
     

    Attached Files:

  2. marshmat
    Joined: Apr 2005
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    marshmat Senior Member

    Hi naupigos / John,

    First question: What software did you use to create the model?

    Looking at the iges file, I see a few things that could be messing up your calculations. The biggest one is that the forebody and afterbody do not match up at midships: the point counts do not match, the u/v directions do not match, and there is thus a gap between the two ends of the ship.

    You can still extract the wetted surface area from this model. If your CAD software doesn't have built in hydrostatics, you can make a copy of the model on a new layer, draw a cutting plane at the waterline, and trim off everything above water. Virtually all surface modellers can give you an area value for the surface that's left.

    If you want to do much more with this model, I think you'll have to rebuild it so the surfaces match up.

    For convenience, in CAD one usually draws the model with the actual dimensions. If a scale drawing is required, the scale dimensioning is usually done on a per-drawing basis, instead of scaling the whole model.
     
  3. naupigos_gr
    Joined: Feb 2009
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    naupigos_gr Junior Member

    hey matt thx for your reply..!
    well our teacher, gave us that "plan", i didnt create it just download it from teacher's website
    already scaled when i recieved it ...!:(
    i use rhino 4.0..i know there a gap i cant fix it :/
    most of the times i save my ship plans in .3dm format

    rhinoceros with marine upgrade has hydrostatics , i use marine upgrade tools when i need to find them
     
  4. naupigos_gr
    Joined: Feb 2009
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    naupigos_gr Junior Member

    i need wetted surface area , because i have to do an exercise with method of froude..you know first calculate for model and then for full size model

    i cant rebuild model or full size vessel , cuz i havent got offsets !just surfaces u see in igs file
     
    Last edited: Feb 5, 2009

  5. Guest625101138

    Guest625101138 Previous Member

    Importing the model I get it to be 92m long. Setting the draft at 6m gives a wetted area of 1815sq.m

    As Mat points out it would sink because of the poorly aligned plating amidship.

    Rick W
     

    Attached Files:

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