Hartmann number

Hartmann number ( Ha ) is a dimensionless number of fluids, that is, gases or liquids. It is defined as the ratio between viscous and magnetically induced frictional forces.

The Hartmann number (English Hartmann number) - named after the Danish physicist Julius Hartmann ( 1881-1951 ) - plays in the calculation and characterization of plasmas such as occur for example in the MGD, an important role.

Definition

  • - Magnetic flux density
  • - Characteristic length of the system
  • - Electrical conductivity
  • - Dynamic viscosity, sometimes

The square of the Hartmann number results in the so-called Chandrasekhar number:

Electromagnetic induction Digital Object Identifier
377243
de