Research And Design Sealing Structure Of Dynamic And Static Frame Of Altitude Simulation Test Facility Based On PTFE

Altitude simulation test facility is an important platform for high-altitude simulation experiments on aero-engines and components of aero-engines.It is indispensable means for development advanced aero-engines and improvement aero-engines.The sealing structure of dynamic and static frame of altitude simulation test facility has great influence on accuracy of aero-engines thrust test.Therefore,research and design the sealing structure of dynamic and static frame of altitude simulation test facility based on Teflon（PTFE）has significantly to improve the sealing structure of dynamic and static frame and improve accuracy of aero-engines thrust test.The dynamic and static frame of altitude simulation test facility adopts non-contact sealed connection structure.The differential pressure between internal flow channel and external environment at connection of dynamic and static frame lead to gas leakage,which seriously affects accuracy of aero-engines thrust test.The article is to solve the above problems.It combined theoretical research,simulation calculation,and experimental verification research influence of non-contact sealing structure parameters（sealing gap,shape of sealing ring cross-sectional,number of sealing rings）on leakage of sealing structure.The research shows that only gap of between sealing ring and static frame is changed,leakage of sealing structure significantly reduced.Trapezoidal section sealing ring has better sealing effect than D-shaped section sealing ring.When only number of sealing rings is changed,leakage of sealing structure changes less.When sealing structure parameters are unchanged and pressure ratio is reduced,leakage of sealing structure will greatly decreased.Through parameter optimization design of sealing structure,sealing characteristic of sealing structure is improved,at the same time,deformation of seal ring under action of gas force is analyzed,which provides reference for detection and maintenance of sealing ring.An experimental system was designed to test the friction coefficient,and the friction coefficient of PTFE and 45 steel was used to calculate the friction resistance of dynamic and static frame.The formula of friction resistance of sealing ring in different states is derived,and the formula of additional thrust resistance of altitude simulation test facility is corrected.The research in this paper has important engineering application value for optimization design of dynamic and static frame sealing structure of altitude simulation test facility and improvement of accuracy of aero-engines thrust test.