基于反旋流的密封气流激振抑制方法及结构参数设计  

Flow-induced vibration suppression method and structural parameter design of the seal with shunt injection

作　　者：曹仲勋 申智勇 汪飞 董雪峰 张乃丹 张万福[2] CAO Zhongxun;SHEN Zhiyong;WANG Fei;DONG Xuefeng;ZHANG Naidan;ZHANG Wanfu(China Energy Science and Technology Research Institute Co.,Ltd.,Nanjing 210046,China;School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]国家能源集团科学技术研究院有限公司,江苏南京210046 [2]上海理工大学能源与动力工程学院,上海200093

出　　处：《热力发电》2024年第3期137-145,共9页Thermal Power Generation

基　　金：国家能源集团科学技术研究院有限公司科技项目(WH2023Y02);国家自然科学基金面上项目(51872361)。

摘　　要：梳齿密封因其结构简单、方便维修及使用寿命长等特点被广泛应用于各类透平机械,反旋流装置可通过影响密封腔室内周向流动,减弱螺旋形效应引起的气流激振问题,提高密封系统稳定性。建立反旋流梳齿密封三维数值模型,计算分析不同结构参数下反旋流喷嘴对密封动力学特性影响。结果表明:反旋流喷嘴倾斜角度越小,系统阻尼越大、稳定性越高,当倾斜角度为30°时,有效阻尼为垂直角度入射时的4倍;反旋流喷嘴形状对密封动力特性及流动特性影响较小,2种喷嘴孔型交叉刚度均为负值且低频下二者交叉刚度差值约为5 k N/m、高频下约为1~2 k N/m;喷嘴数目越多,越能够抑制转子周向流动,利于系统稳定。Labyrinth seals are widely used in various types of turbomachinery due to their simple structure,convenient maintenance,and long service life.The shunt injection devices can reduce the flow-induced vibration caused by the spiral effect and improve the stability of the sealing system by affecting the circumferential flow inside the seal cavity.The three-dimensional numerical models of shunt injection labyrinth seal were established to calculate and analyze the impact of the shunt injection nozzle on the dynamic characteristics of the seal under different structural parameters.The results show that the smaller the tilt angle of the anti-swirl nozzle,the greater the system damping and stability.When the tilt angle is 30°,the effective damping is 4 times that of the vertical angle incident;the shape of the anti-swirl nozzle has a small impact on the sealing dynamic and flow characteristics.The cross stiffness of both nozzle hole types is negative,and the difference in cross stiffness between the two is about 5 kN/m at low frequencies and 1~2 kN/m at high frequencies;the more nozzles there are,the more they can suppress the circumferential flow of the rotor,which is beneficial for system stability.

关 键 词：反旋流 梳齿密封 动力特性 计算流体力学 

分 类 号：TH136[机械工程—机械制造及自动化]