Hartmann number
Encyclopedia
Hartmann number is the ratio of electromagnetic force to the viscous force first introduced by Hartmann. It is defined by:
where
where
-
is the magnetic field -
is the characteristic length scale -
is the electrical conductivity -
is the viscosityViscosityViscosity is a measure of the resistance of a fluid which is being deformed by either shear or tensile stress. In everyday terms , viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, while honey is "thick", having a higher viscosity...