The Elsasser number, Λ, is a dimensionless number in
magnetohydrodynamics
Magnetohydrodynamics (MHD; also called magneto-fluid dynamics or hydromagnetics) is the study of the magnetic properties and behaviour of electrically conducting fluids. Examples of such magnetofluids include plasmas, liquid metals ...
that represents the ratio of magnetic forces to the Coriolis force.
where σ is the
conductivity
Conductivity may refer to:
*Electrical conductivity, a measure of a material's ability to conduct an electric current
**Conductivity (electrolytic), the electrical conductivity of an electrolyte in solution
** Ionic conductivity (solid state), ele ...
of the fluid, ''B'' is the
magnetic field
A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and t ...
, ρ is the density of the fluid, and Ω is the rate of rotation of the body.
Notes
References
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{{Fluiddynamics-stub
Dimensionless numbers of fluid mechanics