Marangoni number

The Marangoni number (Mg) is a dimensionless number named after Italian scientist Carlo Marangoni. The Marangoni number may be regarded as proportional to (thermal-) surface tension forces divided by viscous forces. It is – for example – applicable to bubble and foam research or calculations of cryogenic spacecraft propellant behaviour.

\mathrm{Mg}=-{\frac{d\sigma}{dT}}\frac{1}{\eta \alpha} \cdot L \cdot \Delta T

See also