Study On Controllable Flexible Sealing Performance Used For Rotating Shaft Under Water Hydraulic Condition

In this paper,the sealing performance and tribological characteristics of the rotating sealing pair with different sealing structures and sealing control parameters under water hydraulic sealing conditions were studied.Firstly,the background and significance of developing the controllable flexible sealing were introduced.The research achievements of fluid sealing technology at home and abroad was summarized.The research status,development prospects and technical difficulties were introduced respectively from water hydraulic pressure,rotary dynamic seal and controllable seal these three technical directions.Secondly,the theory of controllable flexible sealing was analyzed.This paper introduced its sealing principle and failure criterion,established its physical deformation model,and analyzed its deformation process of rubber seal ring.Based on tensor function,the relation expressions of contact pressure in different deformation process were given.The lubrication analysis model was established.The lubrication mechanism of friction pair was analyzed,which was composed of rubber seal ring and rotating shaft.Considering the influence of centrifugal force,the modified Reynolds equation was deduced.The main friction and wear mechanism of the sealing ring was discussed and the formula of friction torque between the sealing ring and the rotating shaft was derived.Then,the performance analysis of controllable flexible sealing was carried out.By comparing and analyzing the existing rubber constitutive models,the constitutive model used in this study was determined.3D controllable flexible sealing was simulated and analyzed by ANSYS Workbench.The influence laws of cross-section structure,pressure of control medium,axial pre-compression of seal ring,radial gap of seal baffles and rotation speed on Von-mises stress,deformation displacement,contact pressure and the friction stress between seal ring and rotary shaft were explored.Through regression analysis,the relation expression of the control pressure and the sealed medium pressure under corresponding parameters can provide a reference for finding reliable control methods of controllable flexible seal.Finally,the experimental system of controllable flexible sealing was designed,which was used for water hydraulic rotating condition.By combining the theory with the experiment results,the relationship between control pressure and the sealed medium pressure was studied.