基于梯形齿的磁性液体密封设计与耐压能力分析

Influence of trapezoidal pole teeth on anti-pressure ability of magnetic fluid sealing

为了在磁流体密封结构的密封间隙内获得最大磁感应强度差从而提高磁性液体密封装置的耐压能力,基于一典型的磁性液体密封结构,在磁性液体密封理论基础上,采用有限元仿真计算出磁性液体密封结构中的磁场,从而计算出磁性液体密封耐压能力并对极齿进行了优化。结果表明,改变极齿齿形,增加极齿齿顶部长度,极齿处于饱和磁化,磁阻逐渐减小,极齿间最大磁感应强度的均值逐渐增高,而最小磁感应强度的均值逐渐降低,因此密封间隙的耐压能力增强。继续增加极齿齿顶部宽度,极齿处于不饱和磁化状态,极齿间最大磁感应强度降低的幅度大于最小磁感应强度降低的幅度,因此耐压能力降低。

In order to obtain the maximum magnetic induction difference in the sealing gap of the magnetic fluid sealing structure and improve the pressure resistance of the magnetic liquid sealing device,based on a typical magnetic liquid sealing structure and the magnetic liquid sealing theory,the author optimized the tooth profile of the pole teeth.The magnetic field in the magnetic liquid seal structure is calculated by finite element simulation,and then the pressure resistance of the magnetic liquid seal is calculated.The pole teeth are optimized and the calculation results are analyzed and discussed.The results show that by changing the tooth profile and increasing the top length of the teeth,the teeth are in saturation magnetization,the magnetic resistance gradually decreases,the average value of the maximum magnetic induction strength between the teeth gradually increases,while the average value of the minimum magnetic induction strength gradually decreases,so the pressure resistance of the seal gap increases first.When the top width of pole teeth is increased continuously,the pole teeth are in an unsaturated magnetization state,and the trend of decreasing the maximum magnetic induction intensity between pole teeth is greater than that of decreasing the minimum magnetic induction intensity,so the withstand voltage capability is reduced.