Stability of shaft motion in a radial magnetohydrodynamic bearing of finite length

L. P. Terekhov

Abstract
The stability of the motions of a shaft in a cylindrical MHD bearing of finite length is investigated. The effect of inertia terms in the equations of motion and induced electromagnetic field is not taken into account. The lubricant is considered incompressible and the lubrication gap to be small in comparison with the radius of the bearing. An electromagnetic circuit in which the axial magnetic field and the potential difference between the perfectly conducting journal and bearing is considered. The function of hydrodynamic pressure is sought in the form of a double trigonometric series. It is shown that the method of series expansion is convenient in practice. It is established that, under the assumptions made, the zone of stability of shaft rotation narrows somewhat for the case of an incomplete lubrication gap with increase of the applied field. It is shown that in the stability problem an increase of the relative length of the bearing has a stabilizing effect.