Abstract:In order to further explore the impact mechanism of sealing performance of liquid film seals, taking the upstream pumping spiral groove liquid film seals as a research object, the whirling model of rings was established based on the Schnerr-Sauer cavitation model complying with the conservation of mass. On account of the circular whirling trajectory, the effects of whirling directions on the sealing performance and cavitation of spiral groove liquid film seals were discussed under different operational conditions such as pressure difference, rotating speed and liquid film thickness. The results indicate that, the positive whirling can promote the loadcarrying capacity but aggravate leakage, the reverse whirling decreases the leakage but greatly lowers the loadcarrying capacity, the latter being not conductive to the stability of liquid film seals. When the liquid film thickness is changed, the reverse whirling significantly reduces the loadcarrying capacity,but the positive whirling can promote the loadcarrying capacity relatively smaller in case of larger film thickness.For the liquid film cavitation, the positive whirling acts as a catalyzer, while the reverse whirling inhibits it in the case of changing pressure difference and does not work at lower rotating speed, not being affected by the liquid film thickness.