Numerical Study Of The Dynamic-Behaviour Of Gas Bearings-rotor System

Gas bearings have many advantages, such as high speed and vibration small, whichmeet the requirements of high precision in modern society. Compared with the rollingbearings and the liquid bearings, gas bearings are more preferable and more practical inhigh precision field, the aerospace domain, the medical field and the optical field.Therefore, it’s more and more important to study the static and dynamic characteristicsof gas bearings. This paper tries to find some method and research approach forproduction practice by theoretical study of dynamic behavior of gas bearings.In the study process, the pressure derived with time should not be ignored. For thiscase, time discrete method is used to simplify the Reynolds equations, which containsthe pressure derived with time. Then the weighted residual method combining with thefinite element method is used to discrete the Reynolds equations.Based on the study of dynamic analysis of the gas bearings-rotor system, thedynamic models of cylindrical vortex movement and cone vortex movement are built.The Reynolds and dynamic equations are combined by weak coupling algorithm,and the equations are solved by cyclic iterative method. Matlab programs are used tosolve the iterative process, and the simulated data is recorded during the process ofproblem-solving. According to simulated result, some factors related to the systemstability are analyzed, such as rotor speed, the mass eccentricity and the quality of shaft.At last, combining with non-linear theory, further research into the dynamicbehavior is conducted with axis path method and bifurcation method.By comparing with the physical truth and the theoretical analysis, the reductionprocess, modeling method and the solving ideas of weak coupling are proved correctqualitatively.