The Laplace number (La), also known as the Suratman number (Su), is a dimensionless number used in the characterization of free surface fluid dynamics.
It represents a ratio of surface tension to the momentum-transport (especially dissipation) inside a fluid.
It is named after Pierre-Simon Laplace and Indonesian physicist P. C.
Suratman.
[1] It is defined as follows:[2] where: Laplace number is related to Reynolds number (Re) and Weber number (We) in the following way:[2]