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  #16  
Old 04-14-2016, 08:10 AM
TANSL TANSL is offline
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It is unlikely, quite improbable that GZ curve has a flat area values. Unless you understand as "stability curve" anything else.
A double humped curve stability can exist but is not "very common". It occurs mainly in ships with a forecastle deck that encloses much volume.
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  #17  
Old 04-15-2016, 01:08 AM
xichyu xichyu is offline
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Originally Posted by gonzo View Post
A double humped stability curve is very common. When it has a flat area where the maxima is, the usual graphical solution is to go a fixed distance to the right and left from either side of the flat. Then you pick the center point.
Oh,I forget the “ double humped stability curve” . Thanks
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  #18  
Old 04-15-2016, 07:35 AM
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gonzo gonzo is offline
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I meant to say "not very common"
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  #19  
Old 04-15-2016, 11:13 AM
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PAR PAR is offline
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Actually, when you accurately plot a stability curve, it can have a number of "bumps" in it. Typically when the side deck submerge, a flattening on the curve occurs, then when the cabin or deck structures start to submerge, the curve spikes up again. Depending on how you calculate the curve (many don't include deck structures) and the configuration of the deck, you can have a number of bumps.

In small craft design, the curve is typically hull only, through 180 degrees. This is how I do small craft, knowing the actual AVS may be a bit higher, than the calculations show, but an error toward the higher side isn't a bad thing. On larger craft ,the deck structures have to be included, but not so much on a 22' sloop (as an example) with a small cabin on it's foredeck.
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  #20  
Old 04-15-2016, 07:30 PM
xichyu xichyu is offline
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Originally Posted by gonzo View Post
I meant to say "not very common"
ha ha
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  #21  
Old 04-16-2016, 02:39 AM
xichyu xichyu is offline
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Quote:
Originally Posted by PAR View Post
Actually, when you accurately plot a stability curve, it can have a number of "bumps" in it. Typically when the side deck submerge, a flattening on the curve occurs, then when the cabin or deck structures start to submerge, the curve spikes up again. Depending on how you calculate the curve (many don't include deck structures) and the configuration of the deck, you can have a number of bumps.

In small craft design, the curve is typically hull only, through 180 degrees. This is how I do small craft, knowing the actual AVS may be a bit higher, than the calculations show, but an error toward the higher side isn't a bad thing. On larger craft ,the deck structures have to be included, but not so much on a 22' sloop (as an example) with a small cabin on it's foredeck.
Thanks!
It is useful for me
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