液压测试技术交流会议综述

液压测试是生产及科研中必不可少的环节与手段,提高液压测试技术是发展液压技术的重要措施之一。对于工厂,它能反映产品的质量,对于科研,它能改进老产品,发展新产品,验证新理论。测试技术是一门理沦性与实践性都很强的综合技术,它涉及到流体力学、电工学、系统动力学及统计学等多方面的知识。而其内容又可分为:测试标准、测试方法、测试装置、测     

基于虚拟仪器软件的液压测试系统设计

文章介绍了液压测试系统的硬件设计和软件的开发,讨论了虚拟仪器软件LabVIEW在液压测试系统中的应用.通过对液压测试系统的数据采集和信号处理的深入研究,指出了利用虚拟仪器技术可以使液压测试更加精确与高效,虚拟仪器在液压测试技术领域具有广阔的应用前景.     

应用颗粒测试技术解读液压系统污染控制平衡图

根据液压系统污染控制平衡理论,论述了颗粒测试技术对于实施液压系统污染控制的作用,简要介绍了用颗粒测试技术对液压元件污染敏感度、过滤器过滤比卢和液压系统油液污染度的验证研究方法.     

轧机液压厚度自动控制系统试验技术及设备研究

文章阐述了液压AGC的试验与诊断技术所存在的主要技术问题及研制的重要性，提出了现场原型轧机液压AGC动态负载测试、双方向全行程轧机AGC液压缸摩擦力特性的测试、电液伺服阀流量的宽量程及高精度测试、大电流伺服阀和多级电反馈伺服阀测试等技术策略，介绍了所开发的液压虚拟仪器平台软件及液压AGC的CAT系统。     

液压是一门实验科学——与学习液压的朋友们交流

该文回溯液压技术的理论基础,提醒读者,液压是一门实验科学,只进行数学解析和数字仿真,脱离了实际测试,是不可能真正提高液压产品的水平的。     

采用CAT的液压缸试验台的研究

采用ＣＡＴ的液压缸试验台的研究陈尧明，许福玲，张德贺随着计算机技术的迅速发展，计算机辅助测试技术越来越多地应用在液压产品的质量检测之中。配备有高速Ａ／Ｄ转换装置及相应处理设备的高精度计算机测试系统，不仅可以保证液压元件静态性能的测试精度，而且能准确地...     

采煤机牵引部CAT试验台的设计与研究

通过综合运用计算机技术、自动化仪表及传感器技术的CAT是目前液压传动技术中比较先进的测试方法。此方法应用于采煤机液压系统的测试,极大提高了采煤机的工作可靠性。该文介绍了一种采煤机牵引部试验台的设计及其测试系统,该测试系统液压部采用了先进的CAT系统,测试自动化程度较高。     

搞好试验台技术改造,提高检测手段

搞好试验台技术改造，提高检测手段辽宁省轻工业学校赫辽瓦抚顺比欧西气体工业有限公司孙紫静液压试验台是液压元件出厂前检验产品性能质量的主要测试设备，也是最后一道工艺过程．该设备的功能、用度及工作可靠性的好坏将直接影响出厂产品的质量．因此必须搞好试验台技术...     

液压系统实现功率匹配节约能源的途径

液压传动技术已成为工业机械、工程建筑机械及国防尖端产品不可缺少的重要技术.但由于液压传动系统往往既存在压力损失,又存在流量损失,因此功率损失大、效率低,浪费大量能源.基于对液压系统效率和能耗的分析,提出了液压系统实现功率匹配节约能源的几种途径.     

国家重点研发计划——流体传动与控制

正项目四:液压元件可靠性评估方法与寿命测试技术项目研究目标:该项目实施中,将积累液压元件故障模式与失效案例数据,突破高端液压元件可靠性与寿命测试评估技术,建立液压元件可靠性评估标准,为我国液压元件产品可靠性和市场竞争力的提升提供有力的理论与技术装备支撑,解决工程装备等相关行业在国产化配套中的元件可靠性难题,产生显著的经济效益与社会效益。     

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.