Floodable Length Hydromax

Discussion in 'Software' started by kiddo14, Feb 20, 2018.

  1. kiddo14
    Joined: Apr 2015
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    kiddo14 Junior Member

    Hi
    I was trying to do floodable length calculations on hydromax. I did set Trim(LCG), VCG, Displacement range and criteria as shown in the tutorial available in youtube but I keep getting the following error "Unable to find a condition where the criteria are passed-Displacement 400 Tonne and Permeability 95%" . Did I skipped something ? Any hydromax expert here ?
     
  2. TANSL
    Joined: Sep 2011
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    TANSL Senior Member

    Have you set the stability criteria that the boat must meet?
    Can you show us the file. msd and give the necessary data so that we can reproduce what you are trying?.
     
  3. kiddo14
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    kiddo14 Junior Member

    Hi
    In the criteria I set immersion criteria as Margin line immersion and also checked maximum trim angle, GMt and GMl criteria.
     

    Attached Files:

  4. TANSL
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    TANSL Senior Member

    I do not have time at the moment to analyze the problem but, perhaps, you should define the load condition for which you want to calculate the floodable lengths. I do not know if that will be the problem but I see that no load condition has been defined so far.
     
  5. TANSL
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    TANSL Senior Member

    I think your model has some error that prevents Hydromax from performing the calculation, but I can not detect what error it is.
    Try with this file.
     

    Attached Files:

    • 001.msd
      001.msd
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  6. kiddo14
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    kiddo14 Junior Member

    The same error occurs with your given attachment too.
     
  7. TANSL
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    TANSL Senior Member

    It is true, I have tried it again and, in effect, it gives the same error. Surprising. I can assure you that the first time he did the calculation perfectly. Let me investigate a little more.
     
  8. TANSL
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    TANSL Senior Member

    So far, I am unable to solve the problem, but I'm still working on it. If you find out something, please let me know.
     
  9. kiddo14
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    kiddo14 Junior Member

    The only thing that I found out is that it works for small amount of displacement like 20 to 30 Tonne. But if the displacement is bigger which it should be for this vessel it does not works. I am really perplexed by this
     
  10. kiddo14
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    kiddo14 Junior Member

    Hi TANSL
    I found out the solution for the problem. Its the Margin line . Since I have slopped transom so maxsurf somehow include the transom inside deck. If you turn on the margin line you will see it goes till the end of transom. So when I run floodable length calculation and transom is already immersed(and hydromax thinks deck too) so hydromax stops the calculation. So in the margin line input window if I manually delete the margin lines after my actual deck( in this case delete all margin line points after 0.63m) then everything works fine. So yes If you have a slopped transom you might see this problem. Same problem going to affect the severe wind and rolling criteria too. You will see unrealistic value.
     
  11. TANSL
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    TANSL Senior Member

    Thanks, Kiddo14, I had also tried to "touch up" the margin line, I even built my own model, but I had not achieved anything. Could you upload here to the current .msd file?
     
  12. TANSL
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    TANSL Senior Member

    Yes, now it works perfectly. The truth is that it is totally logical and we (me at least) should have noticed right away. The margin line was so low that it was not submerged only for very small displacements.
     
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  13. kiddo14
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    kiddo14 Junior Member

    Yeah thats true. I also figured it out since F.Length calculation was running at very low displacement (mentioned above) & I was getting unrealistic value in sever wind & rolling where Deck angle immersion matters. So I thought Deck hence margin line must not be defined correctly
     
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