A numerical study on the friction and wear predictions of finger lock chuck in landing gear
A numerical study on the friction and wear predictions of finger lock chuck in landing gear
复制标题
起落架指锁卡盘摩擦磨损预测的数值研究
DOI：
10.1177/0954410016650710
复制
发表时间：
2017-01-01
影响因子：
1.1
通讯作者：
Nie, Hong
中科院分区：
文献类型：
--
作者：
Zhang, Ming;Jiang, Rongmin;Nie, Hong
锁止机构是起落架的重要组成部分，在飞机起飞和着陆过程中，要求锁止起落架。介绍了一种有效的数值模拟预测方法，用于研究未磨损指形锁紧卡盘的摩擦磨损情况，并进行了相关的实验验证了方法的正确性。采用Abaqus/Explicit求解器进行动力学显式求解，利用商业软件包ABAQUS中的用户子程序VFRIC，研究了未磨损指锁式卡盘运动过程中与速率相关的动摩擦系数。摩擦仿真结果表明，在松锁过程中，指形锁紧卡盘发生了较大的变形，最大应力位于指形锁紧卡盘的根部区域，轴向作用力仿真结果与未磨损指形锁紧件的实验结果相差较小。从摩擦能量耗散的角度出发，以接触足印区域内节点摩擦能量密度率作为评价磨损严重程度的指标。编写Python语言命令实现了对ABAQUS后处理的二次开发，图形化显示了指锁式卡盘接触足迹区域的节点摩擦能密度率分布。磨损模拟结果表明，指锁式卡盘的节点摩擦能密度率分布在卡盘凸起部分的两个圆角区域和凸起平台的内侧表面显著集中，表明未磨损的指锁式卡盘投入使用后首先在这些区域发生磨损。将得到的磨损模拟结果与已磨损的指状锁紧卡盘进行500次偏夹加工磨损试验进行对比，结果基本一致。
Locking mechanism is an important part of landing gear, which is required to lock retractable landing gear during taking off and landing processes of aircraft. This paper introduces an effective numerical simulation forecasting method to investigate the friction and wear of unworn finger lock chuck, where an associated experiment was conducted to verify the correctness of the method. The dynamic explicit procedure was adopted in the simulation process with Abaqus/Explicit solver, the user subroutine VFRIC integrated in the commercial package ABAQUS was coded to study the rate-dependent dynamic friction coefficient during the movement of unworn finger lock chuck. The friction simulation results indicate that large deformation occurs in the finger lock chuck during the unlocking–locking process and the maximum stress lies in the root zone of finger lock chuck, the difference of axial acting force between simulation results and experiment results of unworn finger lock is small. From the perspective of frictional energy dissipation, nodal frictional energy density rate within contact footprint regions was taken as the index to assess the wear severity. Python language commands were programmed to realize the secondary development of ABAQUS post-process, the nodal frictional energy density rate distribution in contact footprint regions of finger lock chuck was graphically displayed. The wear simulation results show that the nodal frictional energy density rate distribution of finger lock chuck concentrates significantly at the regions of two rounded corners in the raised portion of chuck and inner side surface of the raised platform, indicating that wear first occurs in these regions after the unworn finger lock chuck is put into use. The wear simulation results obtained was compared with a worn finger lock chuck after 500 times disengagement-stuck processing wear test, and the results are basically accordant.