Fluid-structure Interaction Analysis And Dynamic Analysis Of Hydrostatic Spindle

Hydrostatic spindle are used extensively in the ultra-precision machine tool because of its higher stiffness and load capability. In work process, temperature rise and oil chamber pressure will result in the deformatin of the spindle, which will influence the performance of hydrostatic spindle. Therfore, it is necessary to research the influence of temperature rise and pressure distribution on the static and dynamic characteristic of the hydrostatic spindle.Hydrostatic spindle is the research object of this paper. Firstly, on the basis of the theoretical formula, the static characteristic of the hydrostatic jorunal and thrust bearing is analysed, namely stiffness, flux, and mean temperature rise;Secondly, the finite element model of the hydrostatic spindle is analysed by the FLUENT software, and the temperature distribution and pressure distribution are obtained. Then, the rules of temperature distribution and pressure distribution are analysed;Thirdly, the fluid-structure interaction model of the hydrostatic spindle is established through realizing data exchange between the CFD software FLUENT and FEA software ANSYS. Then the influence of temperature distribution and pressure distribution on the oil clearance is analysed. Based on the deformation value obtained by the simulation, the model of hydrostatic bearing deformed is established, then the influence of temperature rise and pressure distribution on the static characteristic is analysed;Finally, the stiffness characteristics of hydrostatic bearings is converted to spring element.Then the analysis finite element model of hydrostatic spindle system is established. With consideration of temperature rise and pressure distribution, static and hamonic analysis on the hydrostatic spindle system are done. After the analysis, the deformation curves of amplitude-frequency characteristics are obtained. Then the result data is fitted into the transfer function of hydrostatic spindle system. Based on the transfer function of hydrostatic spindle, the dynamic response under the influence of temperature rise and pressure distribution on the dynamic performance of hydrostatic spindle system are analysed.