磁流体润滑螺旋槽机械密封环角变形计算

Calculation of angular deformation of seal ring in a spiral groove mechanical seal lubricated by magnetic fluid

为研究磁流体润滑螺旋槽机械密封稳态运行时密封环的角变形,推导了外磁场作用下磁流体的黏度公式;基于Muijderman窄槽理论,计算了磁流体润滑螺旋槽机械密封压力场和磁流体膜的开启力,分析了操作参数和螺旋槽结构参数对磁流体膜厚度和密封环角变形的影响。结果表明:磁流体膜厚度和密封环角变形随着转速、密封介质压力、电流、槽深、螺旋角的增大而增大,随着堰槽宽比和槽长比的增大而先增大后减小,随着闭合力的增大而减小。为了得到较高、较稳定的动压效应和较小的密封环角变形,应取槽长比为0.8,槽深为2.5~10.0μm,螺旋角为10°~15°。

To study angular deformation of seal ring in a spiral groove mechanical seal lubricated by magnetic fluid under steady state operation,the viscosity formula of magnetic fluid film in external electromagnetic field was obtained,then the pressure and opening force of magnetic fluid film between the end faces in a spiral groove mechanical seal were calculated based on the Muijderman narrow groove theory.The effects of operating parameters of mechanical seal and geometrical parameters of spiral groove on film thickness of magnetic fluid and angular deformation of seal ring were analyzed.Results indicated that the film thickness of magnetic fluid and angular deformation of seal ring increased with the increase of rotating speed,medium pressure,current,groove depth and spiral groove angle,increased first and then decreased with the increase of ratio of groove width to weir and ratio of groove length,and decreased with the increase of closing force.When the ratio of groove length was 0.8,the groove depth was 2.510.0μm,and the angle of spiral groove was 10°15°,the higher and more stable hydrodynamic pressure effect and the smaller deformation could be obtained.