Taylor number

A nondimensional number arising in problems of a rotating viscous fluid. It may be written

where f is the Coriolis parameter (or, for a cylindrical system, twice the rate of rotation of the system), h is representative of the depth of the fluid, and ν is the kinematic viscosity. The square root of the Taylor number is a rotating Reynolds number, and the fourth root is proportional to the ratio of the depth h to the depth of the Ekman layer.