氢气透平膨胀机静压止推轴承参数设计研究

Research on parameters design of aerostatic thrust bearing of hydrogen turbo-expander

为了提高应用于氢气透平膨胀机中的氢气静压止推轴承的静态承载特性,建立了带均压槽的单排环形供气小孔静压止推轴承模型。应用Fluent软件进行仿真计算,分析了节流孔深度、节流孔数目、节流孔分布圆半径、节流孔直径对于轴承静态承载特性的影响。与文献实验值进行对比,验证了仿真模型以及方法的有效性。结果表明,为保证最好的轴承静态承载特性应选择合理的气膜厚度,增大节流孔深度可以减少轴承最大耗气量,节流孔分布圆半径为R=/R_(1)R_(2)时静态承载特性最好,减小节流孔直径以及节流孔数量可以减少轴承耗气量并且增大气膜最大刚度,但会降低轴承承载力与大气膜厚度下刚度。

In order to improve the static characteristics of hydrogen aerostatic thrust bearings used in hydrogen turboexpanders,the model of single-row annular supply orifice aerostatic thrust bearing with pressure equalizing ring groove.The Fluent software was used to analyze the effects of the orifice depth,the orifice number,the orifice distribute radius and the orifice diameter on the static characteristics of the bearing.The effectiveness of the presented simulation model and method was verified by comparing the calculated results with the experimental data.The results show that the gas film thickness should be reasonably selected to ensure the best static characteris-tics of the bearing.Increasing the orifice depth could decrease the maximum bearing gas con-sumption.The static characteristics of the bearing were optimum when the orifice distributed radius R=/R_(1)R_(2).With the decrease in the orifice number and the orifice diameter,the bearing gas consumption will decrease and the maximum gas film stiffness will increase,but the bearing ca-pacity and the stiffness on the large gas film thickness will decrease.