基于NASTRAN的垂直分流器控制优化与疲劳寿命分析  

Control Optimization and Fatigue Life Analysis of Vertical Shunt Based on NASTRAN

作　　者：陈猛 李佳鸿 谢军华 罗俊斌 CHEN Meng;LI Jiahong;XIE Junhua;LUO Junbing(Southwest Forestry University,Kunming 650044,China;Kunming Logan-KSEC Airport System Company Ltd.,Kunming 65005l,China)

机构地区：[1]西南林业大学,云南昆明650044 [2]昆明昆船逻根机场系统有限公司,云南昆明650051

出　　处：《工业技术创新》2023年第1期60-66,共7页Industrial Technology Innovation

基　　金：云南省先进装备智能制造技术重点实验室开放基金课题(项目编号:KLYAEIMTY2022002)。

摘　　要：针对某机场行李分拣线上垂直分流器使用过程中减速电机底部螺栓发生断裂的问题,对螺栓受力来源进行分析,得知主要因素是主连杆的作用力和螺栓预紧力。建立垂直分流器三维模型,应用NASTRAN软件,在Motion模块中通过STEP函数表达电机速度控制方式,获得连杆的受力—时间历程。将速度控制方式优化为0.22 s加速、0.36 s匀速、0.42 s减速,主连杆受力减小约27%。在NASTRAN的Simulation模块中,电机、螺栓均采用混合实体单元,建立有限元模型,以螺栓预紧力和主连杆的轴向力作为载荷,分析得到螺栓所受的Mises应力。比较不同的电机速度控制方式和预紧力对螺栓应力的影响,发现当预紧力为12.5 kN时,螺栓最大Mises应力为114 MPa,为最优解。对最优解进行疲劳寿命分析,最小循环次数大于107次,表明可以避免螺栓断裂。工况改进后,新的垂直分流器使用一年间未再出现断裂现象,在不更换材料、不改变结构的情况下,解决了螺栓断裂问题。Aiming at the problem that the bolt at the bottom of the deceleration motor was broken during the use of deceleration motor in baggage sorting line of an airport, the force source of the bolt was analyzed, knowing that the main factors were the force of the main connecting rod and the pre-tightening force of the bolt. The three-dimensional model of the vertical shunt was established, and the force-time duration of the connecting rod was obtained by using the NASTRAN software to express the control mode of the motor speed through the STEP function in the Motion module. The speed control mode was optimized as 0.22 s acceleration, 0.36 s uniform speed and 0.42 s deceleration, and the force on the main connecting rod was reduced by about 27%. In the Simulation module of NASTRAN, both the motor and the bolt were set as mixed solid elements, and the finite element model was established. The Mises stress on the bolt was analyzed by taking the pre-tightening force of the bolt and the axial force of the main connecting rod as loads. Comparing the influence of different control modes on the motor speed and pre-tightening forces on the bolt stress, it was found that when the pre-tightening force is 12.5 kN, the maximum Mises stress of the bolt was 114 MPa, which was the optimal solution. The fatigue life analysis of the optimal solution showed that the minimum number of cycles was more than 10~7, showing that the bolt break was avoided. After the improvement of the working conditions, the new vertical shunt does not break again within one year, showing that the problem of the bolt break is solved without changing materials and structures.

关 键 词：垂直分流器 NASTRAN Mises应力 疲劳寿命 螺栓 

分 类 号：TH202[机械工程—机械制造及自动化] TP115[自动化与计算机技术—控制理论与控制工程]