Analysis of dynamic characteristics of spiral groove liquid film seal considering cavitation

Abstract

Purpose The purpose of this paper is to investigate the dynamic characteristics of a spiral groove liquid film seal considering the effect of cavitation. Design/methodology/approach A mathematical model of a spiral groove liquid film seal was established based on the mass-conserving Jakobsson–Floberg–Olsson cavitation boundary condition. The film rupture and film reformation boundaries were assumed to be unchanged under infinitesimal perturbation conditions. Governing equations under steady and perturbed states were solved by the finite element method, and then the dynamic characteristics of the spiral groove liquid film seal were theoretically investigated considering the effect of cavitation. Findings The results indicate that dynamic coefficients considering cavitation are smaller than those neglecting cavitation. The difference value is consistent with the change in cavitation area. The liquid film seal does not suffer axial instability whether considering cavitation, but its angular instability is more likely to occur when cavitation is considered. Originality/value For liquid lubricated non-contacting mechanical seals, the dynamic characteristics considering cavitation are investigated. The results are expected to provide a theoretical basis for improving the design method of liquid film seals.