抗侧滚扭杆支座的疲劳特性和结构优化设计

抗侧滚扭杆是轨道车辆转向架上与空气弹簧协同工作,弥补空气弹簧抗侧滚刚度不足,减小车体柔性系数的重要装置部件。其主要由扭杆、扭臂、拉压杆和铰接元件组成。其中的支撑座是安装于转向架或者车体,支撑扭杆的重要零件,其结构多种多样,疲劳寿命十分关键。本文使用计算机仿真软件ANSYS WORKBENCH 15.0对支撑座的结构进行了仿真,预测其疲劳寿命和失效模式,并分析了结构参数和材料对寿命的影响作用。最后对支撑座结构作优化设计,并制作实际样品进行工况试验,验证其效果是否符合优化设计。     

轨道交通车辆扭杆系统刚度设计

抗侧滚扭杆系统的系统刚度是重要的性能参数.文中通过分析在车体侧滚时扭杆系统的变形,研究扭杆系统刚度的影响因素,提出了计算抗侧滚扭杆系统刚度方法.     

抗侧滚扭杆对地铁车辆动力学性能影响分析

采用SIMPACK动力学分析软件建立了某80km/h B型地铁车辆的动力学模型,分析比较了该车辆的动力学性能随抗侧滚扭杆刚度的变化情况。计算结果表明:抗侧滚扭杆装置能显著降低车辆柔度系数、轮轴横向力、车体侧滚角和倾覆系数;对车辆非线性临界速度、脱轨系数则影响不大;对车辆运行平稳性、轮重减载率则存在不利影响。     

CW-2型转向架轴箱定位装置检修工装研制与应用

对CW-2型转向架轴箱转臂定位装置定位转臂节点结构特点进行分析。找出压装中遇到的有关问题提出相应的控制方法,优化了CW-2型定位转臂节点压装工艺流程,有效解决了CW-2型定位转臂节点芯轴与构架梯型槽的配合问题。     

某型动车组动力转向架构架优化设计

转向架作为轨道交通车辆的关键部件,是保证车辆安全、稳定运营的重要一环.构架作为转向架的基础,其强度和动态特性直接影响轨道交通车辆的运营安全.参照JIS E 4207标准,对某型动车组动力转向架构架进行强度评价,根据强度分析和模态分析可以发现构架的薄弱区域,如侧梁上的转臂定位座区域以及侧梁和横梁的连接区域.最终,在确保构架强度合格的条件下,对其进行了最佳的设计优化,增加了构架相对薄弱部分的强度,并且减少了构架整体的质量,达到了轻量化的目的.     

铁道车辆转K6型转向架三维建模与虚拟装配

铁道车辆转K6型转向架是相对车体回转运动的走行装置,主要由摇枕、侧架三大件及轮对组成、制动装置等零部件组合而成。本文利用CAXA实体设计三维软件对转K6型转向架各零部件进行三维建模和虚拟装配,最后通过软件的分解技术生成模拟爆炸图,直观展示了转向架的结构原理和装配关系,对全面了解转向架各零部件的相互位置关系和使用性能要求进而进行干涉检查和可靠性分析,创造了极为有利的条件。     

本期导读

正高速动车转向架构架静强度试验和仿真研究转向架作为支撑车体、保证列车顺利通过曲线的重要部件,其结构强度是否满足设计要求直接关系到列车能否安全运行。以某高速列车动车转向架构架为研究对象,对构架进行静强度测试。试验通过测试构架以及轴箱转臂共同组成的被测试件在静态载荷的作用下产生的变形,并据此计算出相应测点所承受的应力从而判断其是否满足静强度要求。     

履带式折叠越障搜救车的设计

设计一种适应于灾后废墟区或野外进行搜救的多功能越障车.通过蜗轮蜗杆减速器、轴套轴机构及电磁离合器可使越障车翻越较大障碍;三角型履带轮遇到小障碍时,自然向前滚翻,能够顺利翻越小障碍;车体前后均安装侧臂,可实现双向行走和越障.车体上装置采用模块化设计,能够满足人为或自然的灾后救援、反恐行动等不同任务的要求.     

拖车转向架气动噪声数值研究

拖车转向架作为高速列车最主要的气动噪声声源,由于其结构复杂、细小部件多、周围涡流分布紊乱等,对拖车转向架的气动力和气动噪声认识甚少。采用定常RNG k-ε湍流模型与宽频带噪声源模型对拖车转向架的气动阻力、气动升力和气动噪声声源进行初步探讨,并结合非定常大涡模拟与Lighthill声学比拟理论对其进行远场气动噪声分析。计算结果表明:较大漩涡存在于空气弹簧与抗蛇形减振器之间、迎风侧轴箱与构架侧梁外侧的邻近区域;气动阻力、气动升力与运行速度的平方成正比关系,占总气动阻力最大的部件依次为构架(24.02%)、轮对(19.30%)、枕梁(18.08%)、制动闸片、抗侧滚扭杆、制动盘、构架支架和空气弹簧,枕梁的气动升力最大且占总气动升力的157.88%左右;轮对、构架、制动闸片、制动盘、枕梁、垂向减振器、抗侧滚扭杆等凸起部位的迎风侧表面为拖车转向架的气动噪声源,且构架对拖车转向架总噪声的贡献量最多,其次为轮对,然后为盘形制动装置和枕梁,抗侧滚扭杆、垂向减振器、空气弹簧和横向减振器对总噪声的贡献量较少。拖车转向架远场气动噪声是宽频噪声,具有噪声指向性、衰减性和幅值特性等,主要能量集中在28~56 k Hz频率范围内,中心频率为50 Hz、100 Hz、160 Hz在低频部分能量较大且分布规律不随运行速度的改变而变化。     

新西兰机车牵引装置磨损原因分析及改造

对新西兰出口机车转向架牵引装置拐臂销与构架拐臂安装座之间、拐臂销端部与止板之间磨损进行原因分析,阐述制定现场改造工艺的实施过程,并对牵引装置结构提出改造方案。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

Robust Impedance Control of Robots Using an Adaptive Interaction Force Observer

For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type ...     

Research on key techniques of expendable conductivity temperature depth measuring system

This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.     

CHARACTERISTCS OF FLUID FILM IN OPTIMIZED SPIRAL GROOVE MECHANICAL SEAL

In order to investigate the sealing performance variation resulted from the thermal deformation of the end faces, the equations to calculate the fluid film pressure distribution, the bearing force and the leakage rate are derived, for the fluid film both in parallel gap and in wedgy gap. The geometrical parameters of the sealing members are optimized by means of heat transfer analysis and complex method. The analysis results indicate that the shallow spiral grooves can generate hydrodynamic pressure while the rotating ring rotates and the bearing force of the fluid film in spiral groove end faces is much larger than that in the flat end faces. The deformation increases the bearing force of the fluid film in flat end faces, but it decreases the hydrodynamic pressure of the fluid film in spiral groove end faces. The gap dimensions which determine the characteristics of the fluid film is obtained by coupling analysis of the frictional heat and the thermal deformation in consideration of the equilibrium condition of the bearing force and the closing force. For different gap dimensions, the relationship between the closing force and the leakage rate is also investigated, based on which the leakage rate can be controlled by adjusting the closing force.     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

OPTIMIZATION METHOD ON IMPELLER MERIDIONAL CONTOUR AND 3D BLADE

An optimization method for 3D blade and meridional contour of centrifugal or mixed-flow impeller based on the 3D viscous computational fluid dynamics (CFD) analysis is proposed. The blade is indirectly parameterized using the angular momentum and calculated by inverse design method. The design variables are separated into two categories: the meridional contour design variables and the blade design variables. Firstly, only the blade is optimized using genetic algorithm with the meridional contour remained constant. The artificial neural network (ANN) techniques with the training sample data schemed according to design of experiment theory are adopted to construct the response relation between the blade design variables and the impeller performance. Then, based on the ANN approximated relation between the meridional contour design variables and impeller performance, the meridional contour is optimized. Fewer design variables and less calculation effort is required in this method that may be widely used in the optimization of three-dimension impellers. An optimized impeller in a mixed-flow pump, where the head and the efficiency are enhanced by 12.9% and 4.5% respectively, confirms the validity of this newly proposed method.