备件供应保障系统的动力学原理及动态性研究

 针对基层级备件供应保障的供需平衡要求,分析“需求牵引”模式下备件供应保障活动中的反馈控制关系,利用系统动力学分析备件供需系统的动力学数学原理。据此原理建立系统状态空间模型,对备件供应保障系统的动态性进行分析,导出系统达到稳定时关键结构参数的值域,考察物流延迟的存在对系统稳定所产生的影响,并通过系统动力学仿真分析和验证了弱化物流延迟造成的不良影响、恢复系统稳定的条件。在考虑物流延迟的前提下,通过系统动力学仿真对订货周期、订货调整幅度等控制策略进行优化研究。     

高熔点金属电弧熔射成形

以3Cr13高熔点合金进行电弧熔射实验,总结了电弧熔射成形的工艺过程,解决了存在的技术难题;分析了熔射成形件的微观组织以及熔射层表面粗糙度的影响因素,提出了改善熔射层质量的途径和措施。     

EDM电磁信号法放电位置检测一维薄壁模型仿真

从理论分析入手，阐述了电火花加工 (EDM)中电磁信号法放电位置检测的基本原理。结合电路理论、电磁场理论及传感器的原理，建立了一维放电位置与霍尔效应传感器输出之间的理论关系，并在此基础上进行了数值仿真。     

HISTORICAL PROCEDURES AND G-DSG METHOD BASED MANUFACTURING PLANNING

Oriented to CAD/CAM seamless integration, this paper presents an idea for synthetically considering the qualitative history model, which represents the whole course of modeling, and the quantitative geometry model, which contains the extended Brep model, CSG and feature pedigree. History model building captures in background the dynamic interactive definition of engineering requirement and then explicitly conveys the original intention to successive application layers, which isc onductive to the decision support of manufacturing planning in not only automatic geometry re-constructing but also machining set-up. G-DSG theory as an earlier achievement is applied to generate the topology-independent generalized mid-model as an input to manufacturing planning, which istherefore simplified and its accuracy is simultaneously improved. Manufacturing planning lays emphasis on optimizing the mapping in both geometry and function from part itself to detail machining scheme. Comparatively, process planning pays more attention to the mapping to those items like tool, fixture, etc. Theoretically, such an idea is also beneficial to realizing the parametric NC machining trajectory generation and maintaining its dynamic consistency with the update of the design model.     

二次通用旋转组合设计试验在造粒技术领域的应用研究

本文研究了利用二次通用旋转组合设计来进行多因素影响的振动流化床喷雾造粒试验,建立数学模型,得出了具有一定参数价值的最佳操作参数。     

锻造焊接齿坯薄壁受力扇形齿轮的改进

针对航空产品中锻造焊接齿坯薄壁受力扇形齿轮的机械加工，从毛坯、工艺路线、基准选取、加工参数、刀具选择等进行了介绍，重点介绍了关键工序——切制齿轮，为类似零件的加工提供方法、技巧和借鉴。     

Electrochemical machining of a convex strips structure on a revolving part by using site directed power interruption

Revolving parts with complex surface structures are widely used in machinery and mechanical equipment. The ECM process provides its adequacy to cut hard materials with different shapes, and its applications are widely increased, due to its outstanding advantages. In this paper, a new method for machining a convex strips structure on a cylinder by using site directed power interruption(SDPI) in the ECM process is presented. A variable correction value of the power-off time was defined and optimized to obtain the ideal interval for better machining accuracy and stability.The electric field distribution and the simulated convex profiles show that the stray current density can be reduced effectively by using the proposed method. The correction value has an important influence on the machining accuracy. A suitable correction value in the range of 0.6–1.2 s can effectively improve the machining accuracy of the convex strips structure. Experiments were also conducted to verify the proposed method. Results have confirmed that the stray corrosion on the convex strips surface is significantly reduced and the machining accuracy of convex strips structure is remarkably improved by using the proposed method with a suitable correction value in the ECM process. Finally, a convex strip with a height of 2 mm on a thin-wall revolving part was also produced successfully using a correction value of 0.9.     

基于MBD的数字化零件检测技术研究

为了提高零件的检测效率,保证零件质量,研究总结了典型飞机结构件的典型检测特征,提出了基于MBD的检测数据模型,并在Catia下使用CAA进行二次开发,实现了MBD检测数据模型的自动生成和数据的自动提取。研究实现了针对曲面轮廓度检测特征的测量点自动生成算法,并自动转为DMIS格式的测量程序,可供三坐标测量机直接读取,实现从检测特征提取到检测设备运行的自动化。最终可对零件的检测结果做出评价。     

目标成本管理在汽车零部件行业应用研究

汽车零部件行业生命周期相对固定、事先确定销售价格、产量预测较为明确等特点使该行业具有目标成本管理的先天优势。而一个产品在生命期必然面对客户每年提出的降价要求,因此如果简单地运用目标价格扣减目标利润的公式难以真正实现产品盈利的目标。文章认为目标成本的确定应该结合产品生命期内的现金流分析,在满足项目评价指标的前提下,在整个生命期内对产品进行成本规划。文章以KD公司为案例企业,对其基于产品生命期现金流的目标成本管理的具体应用方法进行了研究,肯定了其取得的良好效果。     

高速前飞时旋翼气动载荷计算

针对大速度前飞的特点,我们研制了一套计算大速度前飞旋翼气动载荷的方法和软件,算例计算表明计算值和试验值有较好的吻合度,它不仅在桨叶内段吻合得较好,而且在桨尖这种大载荷区域也是如此;不仅对前进比μ=0.3以下状态符合得较好,而且对μ=0.4,0.45这种高速状态也是如此。这说明本计算方法与软件对大速度前飞旋翼气动载荷计算达到了一定的精度,基本上能满足工程设计的需要。