Study on two different calculation methods for thrust aerostatic bearings with single supply hole at large gas film clearance

摘要

In order to study the applicability of the Reynolds equation and the precise calculation of the flow field at large gas film clearance, the thrust aerostatic bearing with single supply hole was taken as a study subject. Both the finite difference method (FDM) based on Reynolds equation and the finite volume method (FVM) based on N-S equations were used to calculate the two-dimension flow field. For FDM, the Newton iteration method for two-dimension Reynolds equation of thrust aerostatic bearings was deduced, the central difference method was used, the Chebyshev accelerated over-relaxation iterative method was introduced to improve the calculation efficiency; For FVM based on the Fluent software, the structured and partial refinement grids were used, the mixture model of laminar and turbulent models was built and the SIMPLE algorithm was used for solving. The calculation results of the two numerical methods were compared with the experiment ones. The results show FDM based Reynolds equation are not effective to calculate the pressure depression and recovery, but after the pressure recovery, the calculation results agree well with the experiment ones, which can satisfy the engineering requirement, it needs little calculation grids and has a high calculation efficiency. The FVM based on N-S equations is able to calculate the pressure change with a high calculation resolution, which has a low calculation efficiency, and can be used for further study on the characteristics of the flow field.