Stuart number
The Stuart number (N, also known as magnetic interaction parameter) is a dimensionless number of fluids, i.e. gases or liquids.
It is defined as the ratio of electromagnetic to inertial forces, which gives an estimate of the relative importance of a magnetic field on a flow. The Stuart number is relevant for flows of conducting fluids, e.g. in fusion reactors, steel casters or plasmas. [1]
Definition
\[ {\it N} = \frac{Ha^2}{Re} = \frac {B^2 \cdot L_{c} \cdot \sigma}{\rho U} \]
- \(Ha\) – Hartmann number
- \(Re\) – Reynolds number
- \(B\) – magnetic flux density
- \(L_c\) – characteristic length
- \(\sigma\) – electric conductivity
- \(\mu\) – dynamic viscosity, sometimes denoted as \(\eta\)
References
- ↑ D. Lee, H. Choi,: Magnetohydrodynamic turbulent flow in a channel at low magnetic Reynolds number. In: Journal of Fluid Mechanics. 439, 2001, p. 367–394 (doi:10.1017/S0022112001004621).
Further reading
- R. Moreau: Magnetohydrodynamics (= Fluid Mechanics and its Applications. Vol. 3). Kluwer Academic Publishers, Dordrecht u. a. 1990, ISBN 0-7923-0937-5, S. 127.
- P. A. Davidson: An Introduction to Magnetohydrodynamics. Cambridge University Press, Cambridge 2001, ISBN 0-521-79149-9, S. 97.
