The Euler number or cavitation number is a dimensionless number used in flow calculations. It expresses the relationship between a flow's pressure and kinetic energy, and is used to characterize the potential of the flow to cavitate. It is named for Leonhard Euler.

It is defined as

$$

\mathit{Ca}=\frac{p-p_v}{\frac{1}{2}\rho V^2}

where

• $\backslash rho$ is the density of the fluid.
• $p$ is the local pressure.
• $p\_v$ is the vapor pressure of the fluid.
• $V$ is a characteristic velocity of the flow.

See also

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• Reynolds number for use in flow analysis and similarity of flows
• List of topics named after Leonhard Euler

Reference

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• Batchelor, G.K. (1967). An Introduction to Fluid Dynamics. Cambridge University Press. ISBN 0-521-09817-3

Dimensionless numbers | Fluid dynamics