CALCULATION OF FLOOR BEARING WITH FERROMAGNETIC LIQUID OF TURBOGENERATORS OF POWER DISTRIBUTION SYSTEMS

The article discusses ways to solve the problem of wear of the rotor bearings of turbine units at the moments of start–up and shutdown. The concept of a new type of elastic–damping combined sliding bearings, which combines the use of ferromagnetic fluids in the design of multi–blade bearings, is proposed. On the basis of this, a design of a petal bearing with an electromagnetic effect on elastic elements and a ferromagnetic lubricant has been proposed. The properties and features of the use of ferromagnetic fluids in precision engineering as a lubricant are described. A mathematical model of an electromagnetic petal bearing with a ferromagnetic fluid is proposed on the basis of the Reynolds equation from the course of magnetohydrodynamics, Maxwell's equations for a magnetic field, a system of equations in displacements based on the theory of cylindrical shells. An algorithm for the operation of the rotor support during start–up, shutdown, as well as when the power supply of the electromagnets is turned off.

Hopfions

More than 40 years ago, Faddeev proposed the existence of three-dimensional topological solitons classified by the integer-valued Hopf invariant. These solitons are now known as hopfions and have been investigated in a range of systems, including the original model suggested by Faddeev, where a variety of stable knot and link solutions have been computed numerically. Very recently, numerical computations have predicted the existence of nanoscale hopfions in frustrated magnets and experiments have realized micrometer-sized hopfions in chiral ferromagnetic fluids. All these examples of hopfions will be described and their similarities and differences discussed.