Modeling And Simulation Research On Aerostatic Bearing With Orifice Array

Air bearing's characteristics involve supporting without touching, friction-free movement and precise position, and bearing with orifice array is applied significantly in special industrial areas.The performance of orifice arrays was analyzed using turbulent viscosity standard k-εmodel based on FLUENT, and the influence of the number of orifice on characteristics of coupling air film in orifice arrays were obtained. The results provide reference to design of air bearings, and simulation data can be used to building analytical model of film pressure distribution in orifice array.As it is time-consuming to calculate film capacity of large orifice array by CFD method, this thesis has proposed air film's equivalent circuit modeling and simulation method in orifice unit combining with segmented nonlinear interpolation to reduce the computing time. Unit film's equivalent circuit model and interpolation function were established, and then the film capacity of orifice unit was calculated through circuit simulation and interpolation computation. The error is 3.70% compared with the CFD results. Then, equivalent circuit model of 3×4 and 4×4 orifice array were obtained, and the capacity of two arrays were computed quickly. Physical test results of 4×4 orifice array are in good agreement with the result of CFD. Compared with the CFD result, errors of proposed method are determined to be 10.16% and 8.74% respectively.Computing time and error indacate that the model of orifice unit is effective. This method has reduced computing time of large array's capacity, and will be a computational efficient equivalent formula utilized for larger array and array with other structural parameters.