Eötvös Number

Eötvös Number Calculator

Eötvös Number Calculator

Eötvös number is proportional to { (gravitational force) / (surface tension force) } and is used in momentum transfer in general and atomization, and motion of bubbles and droplets calculations in particular. It is equivalent to (Bo). It is normally defined in the following form above.





Characteristic length




Density of bubble/droplet




Density of surrounding fluid



Surface tension

The Eötvös number is named after the Hungarian physicist Loránd Eötvös, who made significant contributions to the study of surface tension and its effects on fluid behavior.

The Eötvös number is often used to predict the behavior of fluid interfaces, such as the shape of liquid drops, the stability of liquid films, and the dynamics of capillary flows. It helps determine whether gravitational effects dominate over surface tension effects or vice versa in a given fluid system.

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