Reynolds Number

Dimensionless ratio of inertial to viscous forces; the x-axis of every friction-coefficient correlation.

Resistancehydrodynamics

Ship speedknLength (LWL)mKinematic viscosity νm²/sSea water at 15 °C = 1.1892e-6 m²/s.

Reynolds number: 1,211,270,770 -

Changing the inputs requires JavaScript. The calculator above shows its default inputs and result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, and limits

\text{Re} = \frac{V \cdot L}{\nu}

Symbol	Meaning	Unit
$V$	Ship speed	m/s
$L$	Waterline length	m
$ν$	Kinematic viscosity	m²/s

Source: ITTC Recommended Procedure 7.5-02-03

In short

Dimensionless ratio of inertial to viscous forces; the x-axis of every friction-coefficient correlation.

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