双级低滞后刷式密封级间不均衡性分析

针对一种结构参数的双级低滞后刷式密封，采用多孔介质模型进行流场计算，对刷丝安装角度以及第二级前板间隙高度和背板间隙高度与分压比的关系进行分析；基于梁弯曲理论和刷丝区域压力分布，采用有限元法计算得到刷丝的受力和变形情况，分析参数对转子所受摩擦扭矩的影响，讨论参数对双级低滞后刷式密封级间不均衡性的影响.分析表明，第一级刷丝安装角度的增大和第二级刷丝安装角的减小能在一定程度上使两级分压趋于均衡.第一级结构参数不变时，第二级的前板间隙高度变化对级间不均衡性影响不大，背板间隙高度在特定值时，两级可达到均衡状态.

Inter-stage imbalance analysis of two-stage low hysteresis brush seal

The flow field of a two-stage low hysteresis brush seal with certain structure was computed with porous medium model. The relationship between seal installation angles, front and back plate gap clearance height of the second stage and partial pressure ratio were also analyzed. Based on cantilever beam theory and the pressure distribution, bristle forces and deflections were calculated with the finite element method, and the effects of parameters on friction torque and inter-stage imbalance were discussed. The result indicates that, increase of the first stage bristle angle and decrease of the second stage bristle angle could make the partial pressure tend to equilibrium. With the given structure of first stage seal, different front plate gap clearance heights of the second stage seal have little effect on inter-stage imbalance, and a specific back plate gap clearance height can make the two stages get an equilibrium state.