VSV调节机构阻滞力和调节精度的归因分析

Attribution analysis of blocking force and adjustment accuracy of adjusting mechanism of variable stator vane

基于ANCF方法和摩擦力的NURBS表达算法,构建了考虑装配间隙、尺寸公差、关键件柔性、热影响以及接触摩擦等因素的复杂VSV调节机构的刚柔耦合动力学模型,并依据部件空间分布关系和参数化表述开发了VSV调节机构的快速自动化建模流程,大大提升了建模效率。分别对VSV调节机构的单级模拟气动实验及热态联调实验状态进行了对比仿真,结果表明,所构建的VSV调节机构模型在阻滞力仿真方面具有较高的可信度,且气动力引起的摩擦力矩是造成机构阻滞力、角度调节迟滞和调节精度下降的主要原因,气动力矩对机构阻滞力和角度迟滞影响不明显,关键件柔性对阻滞力影响较小,但却是调节精度降低的内在因素。

Based on the Absolute Nodal Coordinate Formulation(ANCF)method and the NURBS expression algorithm of friction,a rigid-flexible coupling dynamics model of a complex adjusting mechanism of Variable Stator Vane(VSV)is built,taking into account factors such as the assembly clearances,dimensional tolerances,flexibility of key components,thermal aerodynamic load,and contact friction.According to the parametric representation and the spatial distribution relationship among the components,a rapid automatic modeling process of multibody dynamics for the VSV adjusting mechanism is developed,considerably improving the modeling efficiency.The simulation results of the single-stage experiment cases with emulated thermal aerodynamic loads and the multiple-stage joint commissioning experiment cases with thermal aerodynamic loads of the VSV adjusting mechanism show that the multibody dynamics model has high reliability in the simulation of the blocking force.The friction torque induced by the force components of the aerodynamic load is the main cause of the blocking force,the retardation of the adjustment angle and the reduction of adjustment accuracy of the VSV mechanism.The influence of the torque components of the aerodynamic load on the blocking force and the retardation of the adjustment angle is not obvious.Despite its little effect on the blocking force,the flexibility of the key component is an intrinsic factor that reduces the adjustment accuracy.