Research On Dynamic Performance Of Flotation Cushion Based On Elastic Plate

With the development of science and technology, the precision and ultra-precision processing technology was born, which puts forward more stringent requirements to aerostatic bearings that are important components of the precision and ultra-precision processing equipment. Gas's inherent nature restricts the improvement of the aerostatic bearing's performance. So how to study the performance of aerostatic bearing and then to optimize the structure of aerostatic bearing is still a research priority in the domain of gas lubrication, which is also the research purpose of this paper.In this paper, flotation cushion, also named aerostatic thrust bearing, is the study object. Reynolds equation is decomposed using the perturbation method, which gives the dynamic mathematic model of the flotation cushion in cartesian coordinate system, combined with the mechanical model. The discretization and boundary condition of the dynamic mathematic model are obtained by finite difference method. With the Successive Over-Relaxation method, numerical calculation and simulation analysis of the flotation cushion's performance are done in MATLAB through programing. Finally, the dynamic stiffness and damping coefficient of the flotation cushion are known.A test-bed is developed, in order to to measure performance of aerostatic thrust bearing. It is a kind of precise and automatic laboratory device and has functions of testing bearing gap. pressure distribution, load capacity and gas film thickness. The test-bed applies balance of tense and compressed springs to supply working force, uses force senser to measure load and uses single coordinate table to achieve continious measuring of pressure distribution.The bearing characteristic and damping characteristic of the notation cushion are known by experiment.The result shows that the experimental data is consistent with the numerical data.The mathematical modeling and numerical analysis in this paper are available.Two new structure flotation cushion are designed, but there are a lot of difficulties when trying to bond the elastic plate to the body of the flotation cushion. So that the bearing characteristic and damping characteristic of the two new structure flotation cushion can not be known by experiment. It need to be resolved in future work.