Papers by Author: S.H. Xiao

Abstract: In this paper，the characteristics of GD-II built-in motorized spindle is introduced；the thermal features of the frameless motor and the hybrid bearings have been studied；the 2D temperature field model has also been developed by finite element method．The results of the calculation show that a good efficiency of heat transferring has been achieved with the oil-air lubrication and oil-water heat exchanger．

Abstract: For the design and application of ultra-high speed aerostatic spindle, it is often difficult to determine the load capacity of bearing gas film because of nonlinear problem, especially when the gas film is very thin. As ultra-high speed aerostatic spindle is working, rotational velocity of spindle ranges up to 300,000 rpm, while Reynolds number of air flow also increases in aerostatic bearing, so we need to consider the impact of gas inertia on the load capacity. In order to improve design accuracy of ultra-high speed aerostatic spindle, it is vitally necessary to consider hydrodynamic effect of aerostatic bearings. By using finite element analysis software ANSYS software as analysis platform, through finite element the analysis of the internal flow field of aerostatic thrust bearing, this paper obtains the relationship of rotation speed and load capacity of aerostatic thrust bearing.

Abstract: The sintered neodymium-iron-boron (Nd-Fe-B) material is used in most of PM machines. The kind of PM materials has small tensile strength and cannot withstand large centrifugal force due to high rotational velocity. A nonmagnetic steel enclosure is needed to cover the PM material. The tensile stress of the PM can reduced by pre-pressure applied to the outer surface of the PM through shrink-fitting into the enclosure. Based on the elasticity theory and the elastic-plastic contact theory, in soft ANSYS it is feasibility to establish a finite element mechanical model of interference fit between the enclosure and motor rotor PM at high rotating speed. This paper simulates the effects of the temperature and rotating speed (centrifugal force) on the displacement and the contact pressure on the interference-fitting surfaces .By finite element non-linear contact model analysis, if setting up right fit clearance, this paper could ensure the security of the PM rotor under rotational velocity up to 300,000 r/min high and temperature up to 150°C.