do any one have any emperical formula for calculation of BM

[sujith]

do anyone have any emperical formulas to calculate BMt(vertical distance between center of buoyancy and metacenter) of a ship
input i have is
lenght of vessel
breadth
depth
draft
KB
kG

[Leo Lazauskas]

Originally Posted by sujith

do anyone have any emperical formulas to calculate BMt(vertical distance between center of buoyancy and metacenter) of a ship
input i have is
lenght of vessel
breadth
depth
draft
KB
kG

Google around for the "U.S. Navy Salvage Engineer's Handbook". It might have some formulae you can use.

[Stephen Ditmore]

You need breadths at stations along the waterline so you can determine the transverse moment if inertia of the waterplane. If you use meters, your result, call it "I(t)", will be in meters^4

BMt = I(t) / displacement (as a volume)

displacement (as a volume) = weight (in metric tonnes) / specific gravity of water
specific gravity of fresh water = 1.000
specific gravity of sea water = 1.025

[CDBarry]

Typically Itt is on the order of Cwp^2 of the Itt of the enclosing rectangle of the waterplane.