Rotation Error Calculation of the Spindle of Precision Centrifuge Under the Coupling Effect of Aerostatic Bearing-Rotor System

For aerostatic bearing-rotor coupling system of precision centrifuge, the method of computational fluid dynamics is used to calculate flow field with variation of eccentricity and the supply pressure. The bearing load capacity related to eccentricity and the supply pressure is derived by a nonlinear fitting function. The dynamic characteristic of bearing-rotor system is built based on the finite element method and the response under the influences of gravity and unbalanced force and nonlinear gas film force is calculated. The calculated results show that the rotation error can meet the design requirements of 10^-6 precision centrifuge.