ISSN:
1089-7666
Source:
AIP Digital Archive
Topics:
Physics
Notes:
A straight arc column operated in a cylindrical tube changes its shape into a helical form if the strength of the arc current, the gas pressure, or a superimposed axial magnetic field exceed marginal values. The helical arc is described by the electromagnetic equations in an electrostatic approximation and by the balances of mass, momentum, and energy. The critical nonlinear term is the Lorentz force. The equations are solved by linear perturbation theory. A first order differential equation is deduced for the helix amplitude from which the stability limit of the cylindrical arc and the growth rate of the helical instability can be evaluated. The ratio of the destabilizing and stabilizing terms in the equation is determined by a dimensionless number, the Maecker number, which comprises integral properties of the arc and properties of the gas.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.866161
