A Theoretical Study of the Turbine Flowmeters With Magnetic Bearing

A novel structure of the turbine flow meter with magnetic bearing is put forward. The analysis of the structure of the turbine flowmeter with magnetic bearing and the theoretical calculation of the characteristics of the magnetic bearing are shown. It is found that there is difference between the axial force and the radial stiffness of the axially magnetized radial magnetic bearing and those of the radially magnetized one, as the shape, the dimensions and the intensity of magnetization are same. The universal model, which ignores the effects of the curvature on the accuracy of the calculation and deals with the magnetic rings as infinite long line magnets, is only suitable for the case of all the magnetic ring section dimensions are very small in comparison with the ring radius, and those are less than or equal to the gap between the two rings. The numerical integral model is accurate, which is based on the method of equivalent charges of magnetism and the direction of magnetization. The preliminary discussion of the problems occurred during the development of the turbine meter is shown also.