发散型阶梯式磁流体密封的磁场有限元分析

Magnetic field element finite analysis of diverging stepped magnetic fluid seals

阶梯式磁流体密封结构是一种在阶梯式迷宫密封基础上提出的用以提高普通磁流体密封耐压能力的新型密封结构.为了在阶梯式磁流体密封结构密封间隙内获得最大磁能积,在阶梯式磁流体密封理论的基础上,对一种具有二级磁源的发散型阶梯式磁流体密封结构进行了磁路设计,同时采用有限元法数值计算出密封间隙内的磁场分布从而计算出阶梯式磁流体密封耐压能力,并对计算结果进行了分析和讨论.结果表明:发散型阶梯式磁流体密封耐压能力随着径向密封间隙的增大而减小;永磁体与极靴结合处的漏磁是导致磁路法设计的发散型阶梯式磁流体密封结构耐压能力偏高的原因.

A new type of the stepped magnetic fluid seal is proposed based on the stepped labyrinth seal to improve universal magnetic fluid seal capacity. To obtain the maximum magnetic energy product, the magnetic circuit design was performed for diverging stepped magnetic fluid seal with two magnetic sources on the basis of stepped magnetic fluid seal theory. The magnetic field element finite method was adopted to calculate magnetic field distribution and stepped magnetic fluid seal capacity. The results are analyzed and discussed. It is demonstrated that the diverging stepped magnetic fluid seal capacity decrease with the increasing height of the radial sealing gap; magnetic field leakages at the connections of pole pieces and permanent magnets result in the sealing capacity of stepped magnetic fluid seal higher than universal magnetic fluid seal.