Magnetic fluid bearing

Abstract

Magnetic fluid bearing is a sliding bearing with conductive fluid as lubricant and an external magnetic field. It is a new type of bearing developed in the 1960s with nuclear power equipment. The commonly used conductive fluids are: molten sodium, potassium and sodium potassium eutectic alloy at high temperature; Mercury is used at room temperature.

Principle and application

The magnetic fluid bearing can be made into hydrodynamic bearing and hydrostatic bearing, which can be divided into cylindrical radial bearing, plane thrust bearing, spherical bearing and tapered bearing according to the structure. FIG. 1 shows the magneto-hydrodynamic radial bearing and FIG. 2 the magneto-hydrodynamic thrust bearing. A magnetic field is generated by a permanent magnet or electromagnetic coil in a direction perpendicular to the flow direction of the conducting fluid. Fluid of the induced current and magnetic field interact to produce Lorentz force, its size and the conductivity of the fluid, speed, and magnetic induction intensity is proportional to square of the direction opposite to the direction of fluid flow, function block movement of fluid, the fluid of equivalent viscosity multiply, thus greatly improve the bearing capacity.