基于旋转法的发动机润滑油黏度检测技术研究

在传统旋转法基础上,提出一种新型的旋转式黏度在线测量方法。该方法利用流体力学相关理论对转子旋转时的黏滞力矩进行分析,通过建立传感器直流电机电流和油液黏滞力矩的关系来仿真计算油液黏度。研发一种发动机润滑油黏度在线检测传感器,通过高低温试验测试传感器对润滑油黏度的响应,并对传感器进行标定。结果表明,该传感器对油液黏度变化具有较快的响应与较高的灵敏度,结构简单,稳定可靠,克服了传统黏度计测量时间长、对环境要求苛刻、尺寸较大且价格昂贵的缺点。     

新型自补偿在线润滑油水分监测传感器响应特性试验研究

目前基于油液介电常数的变化来在线监测润滑油品质和含水率的传感器,存在着需要对传感器输出值进行温度补偿的问题。研究一种具有自动温度补偿功能的在线润滑油水分监测传感器,通过实验考察温度和润滑油中水分含量对传感器的响应灵敏度和动态响应稳定性的影响。实验结果表明,该型传感器无需温度和其他补偿,对润滑油中水分的变化具有较高的线性响应和灵敏度,能准确测量润滑油中的水分含量,且稳定可靠。     

齿轮箱润滑油在线监测系统总体设计

润滑油品质在线监测可以提高齿轮箱系统的故障监测水平.设计一种齿轮箱润滑油在线监测系统,根据油液检测的相关知识建立整体结构,合理选用系统前端的传感器单元,介绍了通信部分的设计,进行上位机软件设计,给出系统的软件模块及界面设计,并利用数据库进行辅助分析.该监测系统对于提高齿轮箱故障监测水平具有重要意义.     

基于光吸收的润滑油劣化传感技术研究

根据润滑油老化后颜色变深的特性,研究一种基于光吸收的润滑油劣化传感技术来测定润滑油的颜色,或直接检测润滑油的劣化状态。根据这个思路,设计开发一款油液颜色传感器,可实时在线采集润滑油的颜色信息,并将数据发送到PC端的数据库中。设计润滑油高温老化方案,并采用实验室色度仪和颜色传感器定期监测润滑油老化样品。结果表明:随着老化时间的增加,润滑油的目视颜色不断加深;通过对强制老化油液的检测与对比分析发现,所研发的传感器的颜色输出、光强输出与实验室测得的润滑油色号之间都具有很强的相关性,表明该油液颜色传感器可用于检测油液的颜色变化和劣化程度。     

大型内燃机组润滑油换型方案制定与实施方法

为实现某进口关键大型机组润滑油国产化改造,制定润滑油换型方案与实施方法。首先通过现场调研、原润滑油和替代润滑油的混容试验,确定替代的润滑油品种;然后提出详细的换油方案包括油品更换的方式和更换时间、油样取样周期等;最后对机组换油后润滑油各项指标进行监测,在运行4 000 h后进行对机组摩擦副进行磨损情况检测。油液监测结果表明,油品各项指标(黏度、闪点、水分、碱值等)及元素含量均处于正常范围,拆机检测表明,气缸内部、连杆轴瓦、活塞磨损均处于正常水平,验证了该润滑油换型方案的可行性。     

发动机润滑油液质量在线监测传感器研究

开发一种发动机润滑油质量在线监测传感器。该传感器利用多波长光来感知润滑油质量变化情况,对润滑油具有较好的区分能力。实验研究光源强度变化、温度变化对该传感器检测精度的影响,并考察其检测稳定性和对不同等级润滑油的区分能力。结果表明,传感器在实验室条件下能够有效地检测润滑油的质量,且受光源强度变化和环境温度变化的影响较小,具有良好的工作稳定性。     

船舶柴油机在线油液监测传感器的安装设计

论述常见的在线水分/黏度/磨损颗粒量传感器的选取及设计安装.针对船舶柴油机干式和湿式润滑系统的特点,提出不同的在线油液监测传感器的设计安装方法,并进行试验研究.结果表明,按该方法设计安装的柴油机在线油液监测传感器测试稳定性好,不仅满足油液在线监测的取样要求,且大大降低了传感器加工安装的难度.     

串口和以太网通信技术在油液在线监测系统中的应用

油液在线监测是设备润滑磨损状态监测技术发展的重要方向,而通信技术在油液在线监测控制系统中有着举足轻重的作用.针对设备润滑磨损监控开发的油液在线监测系统由上位机和下位机组成,采用以太网技术实现上、下位机的通信.上位机实现对被监测润滑油参数的实时显示、趋势分析、数据存储、数据导出、故障报警及诊断等;下位机集磨损、黏度等多种传感器采用PC104实现被监测润滑油数据的采集与处理,并利用嵌入式处理器中的异步通信接口(串口技术)与PC104进行数据交换,从而实现该技术在设备油液在线监测系统中的应用.     

基于FPS传感器的润滑油品质车载监测系统

使用FPS油品传感器测量柴油机润滑油的黏度和介电常数,并将其标准化后建立润滑油的实车监测模型.使用该模型对某重型柴油机润滑油进行监测,所测量结果与使用石油产品运动黏度测定仪测量的结果一致.因此,采用该模型可监测柴油机润滑系统的技术状况,为实车机油的在线监测和按质换油提供了一种新方法.     

新型电化学阻抗谱在线润滑油含水率监测传感器的测试

介绍一种电化学阻抗谱在线润滑油含水率传感器,并通过试验测试其性能.结果表明,该传感器可在线准确测定润滑油含水量,监测润滑油中水分含量的变化趋势,防止因冷却器泄漏、密封垫漏水等造成的润滑油中含水量短时间内显著增加而引起的设备重大事故的发生.该传感器可直接安装于润滑油通路中,具有较强的抗电磁干扰性能,在润滑油质量实时监测和机械设备故障诊断中具有广泛应用.     

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.     

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。     

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。     

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...     

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.     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

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.