数控编程的工艺分析

介绍数控编程时 ,在编写加工工艺的过程中所要进行的零件安装方法、程序原点和换刀点、加工路线、程序编制允许误差等的确定中应注意的问题和建议     

变转速液压系统瞬时转速测量与误差分析

为实时监测柱塞马达的运行状态,准确测量瞬时转速,结合基于工控机与数据采集卡的瞬时转速测量原理与算法,讨论了数据量化误差的主要来源、影响机理以及处理方法,利用LabVIEW与Matlab混合编程的方法,设计了变转速液压系统柱塞马达瞬时转速的测量系统,通过实验验证了测速系统的可行性.仿真与实验结果表明,采样频率对马达转速测量具有重要影响.提高采样频率可以减小数据量化误差、提高测量精度.     

基于减速机漏油问题的分析与防治

针对减速机漏油的现象进行了详细分析,重点介绍了造成减速机漏油的各种原因.通过对漏油减速机实施相应改造与防治,基本解决了减速机漏油的问题.     

高速轿车车身脉动压力的数值分析

分析了高速轿车气流噪声的产生原理,通过求解Lighthill方程得出车辆外部气流噪声只与车身表面的脉动压力有关。采用RNG k-ε和LES相结合的方法求解车外流场,对三个速度下车辆外部流场和表面脉动压力进行仿真模拟,并分析了车辆外流场的特性,得到了车身关键点处的脉动压力级,并将左侧窗中部分监测点的脉动压力级的计算值和实验值进行了对比,得出两者变化趋势基本一致,误差低于5%。经计算分析表明,用大涡模拟方法来计算汽车脉动压力是可行的。     

Sensitivity analysis of suspension characteristics for Korean high speed train

The dynamic performance of railway vehicle is normally expressed as stability, safety and ride comfort, and is affected by mass properties, suspension characteristics, contact mechanism between a wheel and a rail, etc. This paper describes the procedure of sensitivity analysis between some of the suspension characteristics of the Korean high speed train (KHST) as the design variables and the dynamic performance as the response variables; and it analyzes the results of sensitivity characteristics for the design variables, comparing two different approximated approach processes known as the response surface model formulated in a polynomial equation and neural network model formulated in a processing code. Analyzing the suspension characteristics for KHST, the approximated method creating meta-models consisted of 29 design variables and 46 performance indexes, which are applied in this paper. The models were coded by using the correlation information between the design variables and the performance indexes made by the 66 times iterative simulations according to the design of experimental method. The table consists of the orthogonal array L32 and the D-Optimal design table. The results show that the proposed sensitivity analysis procedure is very efficient and simply applicable for a complex mechanical system such as railway vehicle system. Also they show that the two models applied in this paper have similar tendency in the view of the sensitivity order of the design variables. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. ChanKyoung Park received B.S., M.S., and Ph.D. degrees in Mechanical Engineering from Hanyang University in 1987, 1989, and 2004, respectively. Dr. Park is currently a Principal Researcher at the Korea Railroad Research Institute in Euwang, Korea. His research interests are in the area of high speed train dynamics and system engineering of trains.     

圆容栅传感器原理及其误差分析

圆容栅是在传统容栅技术基础上发展起来的新型传感器技术。圆容栅传感器是角行程传感器,其抗干扰能力进一步增强,测量范围进一步增大。     

模态分析方法综述

综述模态分析在研究结构动力特性中的应用,介绍模态分析的两大方法:数值模态分析与试验模态分析。并着重介绍目前的研究热点———工作模态分析,对其方法存在的问题进行评述。     

高速圆柱滚子轴承动力学分析

建立相应坐标系,对滚动轴承中滚子与滚道、滚子与保持架、保持架与引导套圈之间的相互几何作用进行分析,计算出各部件之间作用力和力矩,采用牛顿-欧拉方程建立6自由度滚动轴承动力学模型,对滚动轴承进行动力学分析,为圆柱滚子轴承设计提供理论依据。     

数值模拟在产品认证中的应用研究

以美国ANSI/BIFMAX5.12002标准中对通用办公用椅底座静态强度测试要求为例,采用MSC.Marc对一种铝合金底座进行了有限元数值模拟。在此模拟的基础上,采用正交试验设计方法,研究设计此种底座的三个主要设计参数对底座测试强度的影响规律,并依据此规律进行回归分析,根据分析结果,对此种底座进行结构优化使其在满足测试强度要求的前提下轻量化。     

高速切削热及温度预测研究进展

切削热和温度问题是研究高速切削加工的一个重要参数指标,对刀具磨损、刀具寿命、表面质量、加工效率和零件精度等都具有很大影响。目前,高速切削热和温度问题主要通过试验法、解析法及数值分析法来进行分析。这些方法各有优缺点,给定状况下切削热问题的最佳分析方法的选择主要取决于方法的可操作性、过程的力学特性、分析的准确性及设施的经济性等因素。从正反两方面简要介绍了上述三种方法的各自特点及其研究进展,并对高速切削过程热及温度预测方法的发展方向进行了初步探讨。