Morton Number

Morton number, abbreviated as Mo, a dimensionless number, is the shape of bubbles or drops moving in a surrounding fluid or continuous phase.

 

Morton Number formula
\( Mo \;=\;  g \; \mu^4 \; \Delta \rho \;/\; \rho^2 \; \sigma^3 \)
Symbol	English	Metric
\( Mo \) = Morton number	\(dimensionless\)
\( g \) = gravitational acceleration	\(ft\;/\;sec^2\)	\(m\;/\;s^2\)
\( \mu \) (Greek symbol mu) = dynamic viscosity of surrounding fluid	\(lbf-sec\;/\;ft^2\)	\( Pa-s \)
\( \Delta \rho \) = density differential in the phases	\(lbm\;/\;ft^3\)	\(kg\;/\;m^3\)
\( \rho \) (Greek symbol rho) = density of surrounding fluid	\(lbm\;/\;ft^3\)	\(kg\;/\;m^3\)
\( \sigma \) (Greek symbol sigma) = surface tension coefficient	\(lbf\;/\;ft\)	\(N\;/\;m\)