一字槽柱面气膜两种参数拟合优化分析

Two-parameter Fitting Optimization Analysis of Gas Film on Grooved Cylindrical Sruface

针对柱面气膜密封中的一字槽结构,采用三维建模软件SolidWorks建立关于转速、压差、槽数、槽深、偏心率及长宽比参数的柱面气膜模型,利用流体仿真软件Fluent进行气膜流场仿真。通过改变单一变量转速、压差、槽数、槽深、偏心率及长宽比气膜参数,分析气膜的泄漏量、浮升力及气膜刚度的变化规律,对得到的密封性能变化曲线,采用力漏比、刚漏比拟合曲线对操作参数、槽型参数及密封面结构参数进行优化分析,得到合理的转速、压差、槽数、槽深、偏心率及槽长宽比参数。结果表明:在转速35000 r/min,压差为0.4 MPa,槽数为18,槽深为7μm,偏心率为0.4,槽长宽比为1.8时,一字槽柱面气膜模型得到最优的力漏比与刚漏比,密封性能达到相对最优值。

Aiming at the grooved structure in the cylindrical gas film seal,the three-dimensional modeling software SolidWorks is used to establish the cylindrical gas film model on the parameters of speed,pressure difference,groove number,groove depth,eccentricity and length-to-width ratio.Fluid simulation software Fluent is used to perform gas film flow field simulation.By changing the single variable speed,pressure difference,groove number,groove depth,eccentricity and aspect ratio gas film parameters,analyze the change law of gas film leakage,buoyancy and film stiffness,and obtain the sealing performance change curve.The force-to-leak ratio and stiffness-to-leak ratio fitting curves are used to optimize and analyze the operating parameters,groove parameters and sealing surface structure parameters to obtain reasonable speed,pressure difference,groove number,groove depth,eccentricity and groove length-to-width ratio parameters.The results show that,when the rotation speed is 35000 r/min,the pressure difference is 0.4 MPa,the groove number is 18,the groove depth is 7μm,the eccentricity is 0.4,and the groove length-to-width ratio is 1.8,the grooved cylindrical gas film model obtains the optimal force-to-leak and stiffness-to-leak ratio,the sealing performance reaches the relatively optimal value.