Numerical and experimental study on pole teeth interlaced divergent ferrofluid seals with single magnetic source

For the improvement of pressure resistance in ferrofluid seal with a small gap, a structure of divergent ferrofluid seal (FS) with alternating pole teeth (PT) was proposed in this paper. Distribution of the magnetic field in the seal gap (SG) is analyzed by using the magnetic field finite element method, and the theoretical pressure resistance (PR) is calculated by using the step ferrofluid seal PR theory. Effect of the number of pole teeth and seal gap on its sealing PR were studied experimentally. The PR of the interlaced divergent FS is compared to the experimental findings of a conventional ferrofluid seal structure. The results show that the actual pressure value of the interlaced divergent FS is consistent with its theoretical pressure value well. Compared to the common ferrofluid seal, the interlaced divergent FS has better PR.