In order to further explore the change law of sealing performances of the liquid film seal with inclined-straight grooves,the hydrodynamic lubrication model for the liquid film seal with inclined-straight grooves was established based on the mass conservation cavitation boundary and the liquid film density ratio defined,and the finite difference method was adopted to discretize the governing equation and the SOR method was used to solve the equation.The theoretical and experimental values of cavitation zone in the liquid film were compared and analyzed to verify the accuracy of calculation.The influences of operating conditions,physical property parameter and film thickness groove depth ratio on the hydrodynamic characteristic of liquid film seal with inclined-straight grooves were investigated.Results show that the liquid film seal with larger tilt angle can effectively improve the liquid film load-carrying capacity,increase the leakage and reduce the liquid film cavitation area ratio compared with the smaller one.At the different tilt angles,increasing the rotating speed or the pressure difference can improve the liquid film load-carrying capacity and increase the leakage but the two cases adversely affect the cavitation area ratio.Increasing the viscosity of medium or decreasing the film thickness groove depth ratio can improve the liquid film load-carrying capacity,promote the cavitation and reduce the leakage,but the influence laws of the two cases are different.