Study on lubrication performance of hydrostatic clearance oil film considering multi-factor coupling

The lubricating performance of the clearance oil film determines the machining accuracy of the hydrostatic thrust bearing and the stability of the oil film. From the perspective of working parameters and cavity structure, based on tribological principles and lubrication theory, the clearance oil film temperature rise equation, pressure equation, and viscosity-temperature equation are deduced, and the relationship between load-rotating speed-oil film thickness for different cavity shapes is matched. Through the combination of simulation and experiment, the multi-factor coupling influences on the lubricating performance of the clearance oil film are studied. The study found that the degree of influence on the clearance oil film temperature is in order: rotational speed, hydraulic oil viscosity, load, and cavity depth, and the degree of influence on the clearance oil film pressure is in order: load, hydraulic oil viscosity, rotational speed, and cavity depth. This work provides a theoretical basis for the research and optimization of the lubrication performance of hydrostatic thrust bearings, and provides a research direction for the machining accuracy and running stability of high-speed and heavy-duty CNC equipment.     

雷达方位转台静压轴承支承的计算机辅助设计

静压轴承因其具有独特的特点 ,常用来作为雷达方位转台的支承形式 ,本文根据静压轴承的设计理论 ,编制了计算机辅助设计程序 ,实现了设计过程的智能化、程序化 ,并在工程设计中应用 ,得到良好效果     

PM流量控制器参数对液体静压导轨性能影响的研究

在介绍PM流量控制器基本结构、工作原理以及流量压力特性基础上,推导出基于PM控制器的矩形对置油垫的承载能力、油膜刚度及动态传递函数的表达式。以某机床静压导轨的一对对置油垫为例,重点分析研究PM控制器的三个性能参数比流量cr、初始流量q0和泵压ps之间的相互关系及对油膜承载能力、静刚度及动态特性的影响。研究表明,给定初始流量q0和泵压ps,静刚度随cr增大而逐渐增加,在cr=6.2时静刚度有峰值,这对静压导轨的正常工作不利。比流量cr的合理取值范围为1.2～5.2,此时对置油垫静刚度随着q0的增大和pp减小而增大。基于油膜厚度传递函数表达式,研究敏感油路体积Vo=500 cm3时,在阶跃载荷作用下,不同的比流量cr、初始流量q0以及泵压ps对油膜在时域及频域内动态特性的影响。研究表明:在时域内,cr、q0、pp主要影响着油膜厚度的超调量,随着cr、q0增大以及泵压pp减小,其超调量明显增加。为提高油膜承载的稳定性,减小过渡过程的超调量,可减小cr、q0,增大泵压pp;在频域内,幅频特性曲线峰值处的频率为油液振动的固有频率。随着cr、q0的增加和pp减小,幅值越大,对应的固有频率也有所增大,失稳区频率范围变宽。当...     

综合传动装置液压二次调节试验台的设计与试验研究

在分析履带车辆综合传动装置试验台的原理和组成方案的基础上，利用液压二次调节和实时仿真技术建立了综合传动装置动态仿真试验台的在环硬件和实时仿真环境。确定了综合传动装置负载转矩模拟的实时模型，研究了利用液压二次元件模拟惯性负载的方法，采用非线性死区环节解决了转向阻力矩对转速差的敏感性问题。试验结果表明试验台完全能够满足综合传动装置动态性能试验的需要，为综合传动装置的研制和开发提供了有力的试验手段。     

A decentralized multivariable controller for hydrostatic wind turbine drivetrain

A hydrostatic drivetrain transmits wind turbine energy to a generator. One hydrostatic transmission system (HTS) configuration utilizes a fixed displacement pump and a variable displacement motor. The system dynamics are captured in a nonlinear multi‐input multi‐output mathematical model. This paper introduces a decentralized control configuration based on this model to achieve two desired objectives: maximizing the harvested energy without direct measurement of wind and regulating the frequency of the generator without using power electronic converters. To accomplish these objectives, suitable pairing of control actuators and system responses are identified through nonlinear relative gain arrays (RGA) analysis. The pairing also provides a strong decoupling of control loops. So maximum power point tracking (MPPT) is achieved independently while the generator speed is regulated to maintain the frequency of generated power at 60 Hz. Simulation results demonstrate robust performance of MPPT and frequency regulation in the presence of uncertainties in the turbine and HTS model. We also demonstrate that the RGA paired input‐out control configuration offers superior performance over other possible input–output paired control configurations.     

数控机床导轨结合部动态特性参数优化识别方法研究

数控机床结合部动力学参数识别是机床动力学分析中至关重要的一个环节。针对企业精密卧式加工中心动力学设计的需要,在对该加工中心导轨部件进行模态试验的基础上,提出了一种将模态实验数据与有限元分析模型相集成的导轨结合部动力学参数的优化识别方法。该方法以试验所得各阶模态频率与阻尼比为优化目标,在Matlab与Ansys的集成环境下建立优化任务,采用基于Armijo搜索准则的拟牛顿BFGS算法对结合部动力学参数优化计算。导轨结合部动力学参数优化识别结果表明,所提出优化识别算法的收敛性好、精度能满足工程应用需要。     

玻璃纤维缠绕容器的水压应变测试及分析

简要介绍了直径0．50m的球形及柱形玻璃纤维缠绕压力容器的结构设计；试验研究了在1、2、3、4、5、6和OMPa水压试验条件下，2个球形及2个柱形容器外表面有代表性的7个和9个测点的压力应变；结果表明带金属内衬的纤维缠绕压力容器制造工艺稳定，在6MPa水压时承力纤维的最大应变还不到其极限应变的1／20，说明这类容器的承压潜力巨大。     

FORCE ANALYSIS AND DYNAMIC SIMULATION OF THE PLAIN FLOWDISTRIBUTION PAIR IN A RADIALPISTON HYDRAULIC

ＦＯＲＣＥＡＮＡＬＹＳＩＳＡＮＤＤＹＮＡＭＩＣＳＩＭＵＬＡＴＩＯＮＯＦＴＨＥＰＬＡＩＮＦＬＯＷＤＩＳＴＲＩＢＵＴＩＯＮＰＡＩＲＩＮＡＲＡＤＩＡＬＰＩＳＴＯＮＨＹＤＲＡＵＬＩＣＭＯＴＯＲＬｉＹｕａｎｘｕｎ；ＣｈｅｎＺｈｕｏｒｕ；ＺｈａｎｇＳｈｏｕｌｉ；...     

减小导轨磨床床身-基础系统热变形的一种新方法

为消除环境温度变化和摩擦热对导轨磨床加工精度的影响,对利用自准直设计原理设计的自准直导轨磨床床身-基础系统的热态特性进行了有限元分析和试验研究.结果表明,自准直导轨磨床的床身-基础系统具有很好的精度保持性.     

MM52125A导轨磨床周边磨头的修复方法

针对MM52125A导轨磨床周边磨头的磨损情况,分析原因制定修复方案,并按磨头的技术要求采取切实可行的修复措施,成功地完成了MM52125A周边磨头的修复工作。