# Hartmann Number

Hartmann number, abbreviated as Ha, a dimensionless number, the ratio of electromagnetic force to the viscous.

## Hartmann Number formula |
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\(\large{ Ma = B \; l \; \sqrt{ \frac{ \sigma }{ \mu } } }\) | ||

Symbol |
English |
Metric |

\(\large{ Ha }\) = Hartmann number | \(\large{dimensionless}\) | |

\(\large{ l }\) = characteristic length | \(\large{ft}\) | \(\large{m}\) |

\(\large{ \mu }\) (Greek symbol mu) = dynamic viscosity | \(\large{\frac{lbf-sec}{ft^2}}\) | \(\large{ Pa-s }\) |

\(\large{ \sigma }\) (Greek symbol sigma) = electrical conductivity | - | \(\large{\frac{S}{m}}\) |

\(\large{ B }\) = magnetic field | - | \(\large{T}\) |

Tags: Fluid Equations