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Froude Number

Ratio of inertia to gravity waves; governs hull resistance.

Formula

Fr = \frac{v}{\sqrt{gL}}

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Variables

FrFroude number

vSpeed (m/s)

gGravity 9.81

LWaterline length (m)

Example

v=5 m/s, L=10 m: Fr = 5/√98.1 ≈ 0.50

Did You Know?

Naval architects match the Froude number to test small models that behave like full-size ships.

marine froude hydrodynamics

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