Investigation Into T-groove Cylindrical Gas Film Flow And Thermal Mechanical Coupling Of Flexible System

Cylindrical gas film seal has a bright future because of its excellent sealing performance and its adaptability to large displacement vibration.In recent years,scholars at home and abroad have made some progress in the field of cylindrical gas film seal.As an important part of cylindrical gas film seal,T-groove cylindrical gas film seal is a typical representative of cylindrical gas film bidirectional rotary seal.In this paper,the flow field of T-groove cylindrical gas film seal and the thermal mechanical coupling of floating ring are studied,and the related performance of T-groove cylindrical gas film seal is analyzed,which lays a solid foundation for the practical application of T-groove cylindrical gas film seal.The numerical model of T-groove cylindrical gas film seal is established and the numerical simulation is carried out.The results show that the influence of the average film thickness on the leakage rate is very significant,followed by the film eccentricity.And the influence of the film axial length,T-groove depth and T-groove number on the leakage rate decreases in turn.The effect of the axial length of the film on the buoyancy force is significant,followed by the average film thickness and T-groove depth,while the influence of film eccentricity and T-groove number on the buoyancy force is not obvious.The depth of T-groove exert a more profound influence on the film stiffness than that of the average film thickness and the number of T-groove.The influence of the legnth of film axial and film eccentricity on the film stiffness weakens gradually.With the force coupling,thermal coupling and thermal mechanical coupling,the flexible sysytem composed of floating ring and support ia analyzed by changing floating rings,flecible supporting materials,differential pressure and rotational speed.The results show that the results of thermal coupling are closer to those of thermal coupling under different materials.The pressure value of thermal mechanical coupling to floating ring is higher than that of pressure coupling,but it is lower than that of thermal coupling.With the increase of pressure difference,the maximum deformation increases gradually and shows an exponential increase trend in the case of thermal coupling.The maximum stress decreases with the increase of differentical pressure,which is approximately linear decreasing.Increase with the increase of speed the maximum deformation and maximum stress of floating ring,and both of them are approximately linear increase.The strain of flexible support is similar to that of the flexible support under the circumstance of thermal coupling.The maximum deformation and maximum stress increase with the increase of pressure difference and speed,and both reveal a exponential growth trend.Therefore,the influence of thermal stress should be considered in the future design.