弹簧和密封圈刚度和阻尼对气体端面密封追随性的影响研究

摘要

气体端面密封在实际运行中,静环对动环轴向窜动和角向摆动的跟踪响应能力(追随性)至关重要,优良的追随性能够降低外界干扰对密封稳定性造成的影响.将气体端面密封简化为弹簧-阻尼-质量系统,基于线性化的摄动法求解了密封气膜动态性刚度和阻尼系数,在此基础上研究了弹簧和补偿环用辅助密封圈刚度和阻尼对气体端面密封追随性的影响规律,研究对象包括动压式密封、静压式密封以及动静压混合式密封三种密封形式.研究结果表明:当刚度和阻尼分别小于某数量级时,三种密封在轴向和角向均能具有优异的追随性,随着刚度和阻尼的增加,密封追随性随之变差;同等条件下,动压式密封追随性最好,动静压混合式密封次之,静压式密封最差.%In actual operation of a gas face seal,its stator ring' s ability to track its rotating seal ring' s axial endplay and angle swing (i.e.,its tracking property) is crucial,its excellent tracking property can reduce the influence of external disturbances on the seal stability.Here,a gas face seal assembly was simplified into a spring-damper-mass system.Using the perturbation method based on the linearization,the gas film dynamic stiffness and damping coefficients were solved.Then,the effect laws of stiffness and damping of spring and secondary seal on the tracking property of gas face seal were investigated.Gas face seals had three different end face structures including dynamic pressure one,hydrostatic pressure one and dynamic-hydrostatic pressure hybrid one.Results showed that the three types of seal possess perfect axial and angular tracking properties when stiffness and damping are less than a certain order of magnitude;with increase in stiffness and damping,the tracking property of gas face seal becomes poorer;under the same conditions,the dynamic pressure gas face seal has the best tracking property,followed by the dynamic-hydrostatic pressure hybrid one,and the last is the hydrostatic pressure one.