Numerical Simulation and Optimization Design for Magnetic Fluid Sealing Device
In this paper the principle of magnetic fluid seals is discussed. Based on the finite element software ANSYS, the magnetic field of magnetic fluid sealing device with three slots and four pole teeth is analyzed, and the size parameters of magnetic fluid sealing pole are optimized. The results show that the difference between the maximum and minimum intensity of magnetic field in the area near the shaft determine the sealing capacity of sealing device. The gap of seal should not be larger than 0.3mm. The optimized parameters which are provided for practical design can increase sealing capacity of sealing device as well as decrease the volume of sealing device.
Numerical Computations for Seal Pressure Differential of Magnetic Fluid Seals
The precise computation for the seal capacity of magnetic fluid seals is a rather complicated problem, because this technique concerns with the fundamental theory and analysis method of tribology, electromagnetics and hydrodynamics, and the computations of the seal capacity should be based on the magnetic field computation. Thus, the magnetic field model is analyzed and simplified. On the basis of magnetic fluid seal theory, the magnetic field and isobars in the magnetic fluid are computed with finite element method. The seal pressure differential of the seals is worked out. The relation of the seal pressure differential with the magnetic fluid amount is analyzed. The seal capacity computation method of multi stage seals is presented. The influence of rotating speed on the seal capacity is indicated. It has been found that the computation results agree well with the experimental ones.
Nonlinear Analysis of Magnetic Bearings for Space Technology
The high magnetic energy stored in rare earth-cobalt magnets allows the design of lightweight motors and magnetic bearings for high-speed rotors. Magnetic bearings are not subject to wear and with the ability to operate under high vacuum conditions, they appear ideal for applications requiring high rotational speeds such as 100 000 r/min. Important applications are for turbomolecular pumps, laser scanners, centrifuges, momentum rings for satellite stabilizations, and other uses in space technology. This paper presents a two-dimemsional nonlinear numerical analysis of the magnetic fields in a magnetic bearing, based on magnetostatic assumptions and finite-difference iterative techniques.