Richardson number

The Richardson number is named after Lewis Fry Richardson (1881 - 1953). It is the dimensionless number that expresses the ratio of potential to kinetic energy where g is the acceleration due to gravity, h a representative vertical lengthscale, and u a representative speed.When considering flows in which density differences are small (the Boussinesq approximation), it is common to use the reduced gravity g' and the relevant parameter is the densimetric Richardson number
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