Investigation of micro-vibration reduction method based on dynamic performance analysis of aerostatic bearing

The present work is dedicated to investigating both characteristics of the vortex-induced excitation and the displacement impedance and also weakening the micro-vibration for the aerostatic bearing with orifice type restrictor. Firstly, the numerical simulation is conducted to study the characteristics of the vortex flow in the frequency domain. Further, the displacement impedance is investigated based on an approximate model; the effects of bearing parameters on displacement impedance are also discussed. It is found that the vortex-induced excitation is the dynamic load acting on the floating device, while the displacement impedance reflects the capability of the bearing to withstand the dynamic load. Hence, it is necessary to enhance the displacement impedance for micro-vibration reduction in the bearing. Moreover, the design problem corresponding to the micro-vibration reduction is formulated, and the design optimization is carried out under several given bearing loads. Optimization results show that the micro-vibration can be reduced by increasing the displacement impedance and decreasing the Reynolds number in the flow field. The optimization process can provide an efficient way for reducing the micro-vibration in engineering application.