In fluid mechanics, the Blake number is a nondimensional number showing the ratio of inertial force to viscous force. It is used in momentum transfer in general and in particular for flow of a fluid through beds of solids. It is a generalisation of the Reynolds number for flow through porous media. It is named after the US chemist Frank C. Blake (1892–1926).
Expressed mathematically the Blake number is:
where
{| style="border:0px" | || = || void fraction |- | || = || dynamic viscosity |- | || = || fluid density |- | || = || hydraulic diameter |- | || = || flow velocity
References