摘要：以垂直悬臂提升管道为研究对象,应用有限元软件ADINA对其输送过程进行流固耦合效应特性分析。本文应用有限元软件ADINA对扬矿管道进行管内流体—管道—管外流体三者流固耦合模态分析。首先建立了扬矿管道流固耦合有限元模型,得到了不同输送矿石体积浓度、管道截面尺寸下的前6阶固有频率和振型,继而比较了上述条件下三者耦合、二者耦合及无耦合情况的固有频率,讨论了流固耦合作用对管道固有频率的影响。研究结果表明:(1)扬矿管道流固耦合效应下其固有频率随着管内输送矿石颗粒浓度的增大而降低,考虑管内流体—管道—管外流体三者流固耦合时的管道固有频率较只考虑管内流体—管道二者耦合和不考虑流固耦合时要小,影响系数也相应降低;(2)流体对管道流固耦合固有频率的影响程度随着相对厚度d值的增大而减小,在考虑管内流体—管道—管外流体三者流固耦合时管道固有频率较只考虑管内流体—管道二者耦合相对误差增大;(3)在实际的扬矿管道输送中应该考虑输送流体颗粒浓度、不同相对管道壁厚、管内流体—管道—管外流体三者流固耦合作用对固有频率的影响,尽量使管道固有频率远离工作频率,避免共振情况的发生分析结果对扬矿管道的动态响应计算、结构设计和减振研究具有一定的指导意义。

摘要：This paper reports the reengineering of the assembly processes of printed circuit boards (PCBs) used in *** new designed assembly processes are quite different from the traditional ones,and the business performance is dramatically improved through establishing parallel workstations,off line workstation,merging workstations and organizing a small teamwork who cooperates in stations.“ITHINK”,a software package of business process reengineering (BPR),was used to analyze the current processes and create new *** is a powerful tool of BPR in modeling business processes,“soft” variables and conducting sensitivity *** new assembly processes were tested over a period of 8 hours *** results show that the new processes can increase throughput by 80% with only requiring less additional *** throughput can increase further by 17.5% when a small teamwork cooperates in some stations.

摘要：换挡摇臂是换挡执行机构的关键零件之一,其变形与疲劳寿命对于换挡执行机构的正常工作具有重要影响。文中以某型电控电动式换挡机构的换挡摇臂为研究对象,首先通过多体动力学仿真计算获取载荷谱,基于有限元仿真计算换挡摇臂的应力分布,从而计算出换挡摇臂的变形与疲劳寿命;然后基于变形和疲劳寿命分析结果,选取换挡摇臂关键几何参数为设计变量,以换挡摇臂质量和换挡摇臂变形为目标,以换挡摇臂疲劳寿命为约束条件,通过响应面法对换挡摇臂结构进行多目标设计优化。结果显示,在换挡摇臂质量减轻的同时,变形不增反减。这充分说明文中建立的模型和优化方法具有一定的工程应用价值,为换挡摇臂的设计提供了重要的理论支撑。