In order to investigate the influence of phase change on sealing performance

a liquid film seal phase change model has been established by simultaneous N-S equation and mass transport equation

the governing equations are discretized using a finite volume method

the phase change phenomenon of double spiral groove liquid film seal is simulated and the influence of structural parameters on the phase change region and sealing performance is analyzed. The result shows that the physical parameters change when the phase change occurred

and the flow field in the seal clearance and the pressure distribution at the end face changed obviously. The inner spiral groove can provide stable opening force and ensure the sealing end face to be in good lubrication state

but at the same time lead to the seal leakage increased. The sealing leakage can be reduced

and the sealing performance can be improved by reducing the ratio of groove width to face width

the ratio of groove width to dam width

spiral angle

and groove depth of outer spiral groove or increasing the groove number of outer spiral groove.