摘要
提出一种航空发动机主轴承端适用密封——柔性端面气膜密封。通过对三种密封端面变形情况下的压力控制方程进行求解,获得密封气膜微尺度流场特性的演变规律,并探讨关键密封性能参数与工况条件的相关性。研究结果表明:柔性端面在带压气膜的作用下发生变形,其中波箔片的变形起主导作用,平箔片的影响可忽略不计;相较于刚性端面,柔性端面可有效增大气膜开启力,同时泄漏量也增大;在不同进出口压力比、转速以及初始气膜厚度下,二者部分密封特性呈现出不同的变化趋势,间隙楔形效应使柔性端面的黏性摩擦力矩和气膜刚度变化率均小于刚性端面的相应数值。通过研究结果推断,柔性端面结构可在高速低压工况下具有更稳定的综合密封性能。
A flexible end face gas film seal was proposed for aero-engine shaft end seals.By solving the pressure governing equations under three kinds of sealing end face deformation,the evolution law of the micro-scale flow field characteristics of the sealing gas film was obtained,and the correlation between the key sealing performance parameters and the working conditions was discussed.The research results show that the flexible end face is deformed under the action of the compressed gas film,among which the deformation of the corrugated foil plays a leading role,and the influence of the flat foil is negligible.Compared to the rigid end face,the flexible end face may effectively increase the opening forces of the gas film,and the leakage rate also increases.Under different inlet and outlet pressure ratios,speeds and initial gas film thickness,the sealing characteristics of the two situations show different trends,the gap wedge effectiveness makes the viscous friction torque and gas film stiffness change rate of the flexible end face both are smaller than that of the rigid end face.Inferred from the research results,the flexible end face structure may have a more stable comprehensive sealing performance under high-speed and low-pressure conditions.
作者
徐洁
俞树荣
严如奇
丁雪兴
王世鹏
丁俊华
XU Jie;YU Shurong;YAN Ruqi;DING Xuexing;WANG Shipeng;DING Junhua(College of Petrochemical Technology,Lanzhou University of Technology,Lanzhou,730050)
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2022年第6期656-663,共8页
China Mechanical Engineering
基金
国家重点研发计划(2020YFB200298)
宁波市“科技创新2025”重大专项(20201ZDYF020031)。
关键词
柔性箔片
端面变形
有限差分法
密封特性
数值分析
flexible foil
end face deformation
finite difference method
sealing characteristics
numerical analysis
