中国机械工程

• 机械基础工程 • 上一篇    下一篇

螺旋槽机械密封瞬态启动过程润滑特性

徐鲁帅1;王赟磊1;张帆1;郝木明2;袁小阳1   

  1. 1.西安交通大学现代设计及转子轴承系统教育部重点实验室,西安,710049
    2.中国石油大学(华东)密封技术研究所,青岛,266580
  • 出版日期:2020-08-25 发布日期:2020-09-17
  • 基金资助:
    国家自然科学基金资助项目(51775412,51805409);
    国家重点基础研究发展计划(973计划)资助项目(2015CB057303)

Lubrication Characteristics of Spiral Groove Mechanical Seals during Transient Start-up

XU Lushuai1;WANG Yunlei1;ZHANG Fan1;HAO Muming2;YUAN Xiaoyang1   

  1. 1.Key Laboratory of Education Ministry for Modern Design and Rotor-bearing System, Xi'an Jiaotong University,Xi'an,710049
    2.Institute of Sealing Technology,China University of Petroleum(East China),Qingdao,Shandong,266580
  • Online:2020-08-25 Published:2020-09-17

摘要: 建立了螺旋槽机械密封瞬态启动过程润滑特性的计算模型,耦合求解了含流量因子、接触因子及质量守恒空化边界的雷诺方程、弹塑性粗糙峰接触方程及动力学方程,比较了不同运行工况及结构参数的润滑状态转变过程。结果表明:增速阶段流体承载力与液膜厚度不断增大,粗糙峰承载力逐渐减小至消失;相比较于流体动压润滑状态,混合摩擦状态的液膜刚度较大且振荡幅值明显,在到达脱开转速时刻有较大的轴向速度突变。受挤压效应影响,较小的启动加速度可以在低转速下进入流体润滑状态,较高的外压和较低的内压均有利于润滑状态的转变。随槽数的增加,脱开转速呈先增大后减小趋势,螺旋角与槽深的减小或槽坝比的增大均对润滑状态转变能力起促进作用。

关键词: 机械密封, 瞬态启动, 润滑状态, 挤压效应

Abstract: A mathematical model of lubrication characteristics and sealing performance in spiral groove mechanical seals during transient start-up was established,which included the average Reynolds equation with flow factors, contact factor and JFO(Jakobsson-Floberg-Olsson) (mass conserving) cavitation boundary, elastic-plastic asperity peak contact equation as well as the equations of axial dynamics model. Furthermore, the influences of different working conditions and structural parameters on lubricate regime transformation were compared. Results show that fluid bearing capacity and film thickness increase while the asperity peak contact force gradually decreases to zero during acceleration periods. Mixed lubrication regimes have larger film stiffness and more obvious oscillation amplitude compared with hydrodynamic lubrication regimes. A distinct mutation of axial speed appears when reaching separation speed. The smaller accelerated speed may achieve hydrodynamic lubrication regime at low speed affected by squeezing effect. Both higher outer pressure and lower inner pressure are beneficial to the transformation of lubrication regimes. The separation speed ascends at first and then descends with the increment of groove number. The decrease of spiral angle, groove depth and the increase of groove width ratio play an effective role in the ability of lubrication regime transformation.

Key words: mechanical seal, transient start-up, lubrication regime; squeeze effect

中图分类号: