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ellen lee March 5, 2013 11:08

help with fine/marine!
I am using fine/marine with a planing hull, and the results are not very accurate,I am wondering is it because the froud number is over 3 or still problems with the meshing?

Rombzh March 10, 2013 09:45

You mean the predicted drag is off ? You might want to increase the y+ value, and already prescribe your final trim value in Hexpress.

ellen lee March 12, 2013 10:59

you mean fix the trim? but what if i don‘t know the final trim?

Rombzh March 12, 2013 12:05

Well you could use the trim value you got with your first run, even if forces were off, rotate your geometry in Hexpress and build the mesh.
You can also predict your final trim value with Savitsky's formulae.

lava12005 June 16, 2013 11:36

have you make sure there is no air entrapment below?
This I found to reduce the viscous drag significantly.
Check your mesh resolution on the transom as well, it needs to be fine enough so that the water separate from the hull nicely.

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