共查询到19条相似文献，搜索用时 187 毫秒
1.
利用秒表法找转子静平衡 总被引：1，自引：0，他引：1
张鸣 《淮南职业技术学院学报》2010,10(3):16-18
泵与风机的振动常常是由于转子不平衡不良引起的,现在火力发电厂中高压、高速的大型泵与风机对转子精确平衡的要求更高,特别是在检修、更换转子上的零件后,找平衡成为检修中十分重要的环节,其中秒表法找转子静平衡由于操作简单、省时、误差小等诸多优点而被广泛的应用。 相似文献
2.
谢闰根 《江西教育学院学报》2004,25(3):16-18
转子的不平衡是引起转子失稳的主要因素,对机器有着不利的作用;不平衡的响应特性是一个值得关心的问题。本文建立了单盘转子的运动微分方程,分析了在各个加速度条件下的响应特性,研究表明,不同加速度的不平衡瞬态响应有一定的规律,加速度越大,响应越小,相位越小;同时进动角速度可以分为三个区域波动。这些特性对于转子平衡有一定的指导作用。 相似文献
3.
介绍了水轮机组发电机转子在转动过程中的三种偏心:静偏心、振动偏心和转动偏心,建立了转子在不平衡电磁力作用下的非线性振动微分方程。采用数值方法分析了转动偏心和静偏心对轴系电磁振动特性的影响,结果表明,这两种偏心与电磁力呈非线性关系,随着偏心的增大使不平衡磁拉力作用不断加强,机组的横向振动固有频率有所降低,转子和转轮的振幅不断增大,倍频共振时的振幅也显著加大,转子系统展现出非常复杂的非线性动力学特征。 相似文献
4.
文章介绍了虚拟仪器在转子不平衡故障诊断中的应用,结合硬件设备,采用Labview编程实现了系统的诊断功能,所建实验台对转子故障数据的处理结果表明该系统的诊断效果良好。 相似文献
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6.
风阻效应组合转子是新型航空发动机中最核心最重要的零部件之一,转子结构复杂,装配精度要求高。影响转子的动平衡的因素有很多,且动平衡时不允许去除材料,是国内外研究的热点问题。通过理论分析和现场试验,采用错齿平衡、二倍频分析、计算机辅助编程、影响系数等新工艺方法,攻克了动平衡过程中转子组合后跳动值超差、动平衡值飘移、振动大、旋转不稳定等难题。 相似文献
7.
将样本熵引入旋转机械故障诊断领域,结合形态滤波和样本熵,提出了一种新的转子故障特征提取方法.首先选用最简单的直线结构元素,对实测转子振动信号进行形态滤波降噪处理;然后计算降噪后信号的样本熵,包括转子正常、不平衡、不对中、油膜涡动和碰摩等五种工况的振动信号;最后将样本熵作为特征,对各种故障状态进行评价.转子系统故障诊断的实例验证了该方法的可行性和有效性. 相似文献
8.
第四章交流异步电动机 8.要弄清异步电机转子绕组折合的意义以及具体的折合方法。由于异步电机定、转子绕组之间仅仅通过磁路使它们联系在一起,即满足磁势平衡矿F_1+F_2=F_0。站在定子 相似文献
9.
工业现场中最常用的寻找子动平衡的方法是三圆幅值法.对于不平衡转子,将其三等分后取了三个试重加载位,先讨论了两种特殊情况即原始不平衡矢量位于试重加载位时和原始不平衡量位于两个试重加载中间时平衡质量的大小和平衡位置,后讨论了一般情况平衡平衡质量的大小和平衡位置,从而完成了三圆幅值法寻找动平衡理论的几何证明. 相似文献
10.
《实验室研究与探索》2017,(2):98-101
为了探讨异步电动机的故障运行状态,利用Matlab/Simulink仿真工具中丰富的电机及相关测控模块,结合多回路理论,建立了简易转子断条电机故障仿真模型及三相供电电压不对称时异步电动机运行状态仿真模型,并分析了电机各种运行状态下的定子电流、转速及转矩。同时针对不同故障,采用不同的特征量进行分析。主要包括当电机转子断条时,对电机定子电流进行频谱分析;当电机的三相供电电压不对称时,对不同三相电压不平衡度下的定子电流负序分量进行计算。仿真计算结果表明,频谱分析方法可有效应用于电机转子断条故障的诊断;定子电流负序分量可应用于三相供电电压不平衡的诊断。 相似文献
11.
实现耕地总量动态平衡是我国耕地保护的目标。四川省人多地少的矛盾十分突出,耕地保护的压力巨大。通过对四川省耕地数量和质量的动态平衡情况的考察可以发现,四川省虽然实现了耕地数量的动态平衡,但耕地质量呈现逐年恶化趋势,耕地总量动态平衡的目标还未实现。要实现耕地总量动态平衡目标,四川省必须加强耕地质量保护,在建立耕地质量保护监测服务体系的同时,切实完善耕地保护的经济补偿制度,形成耕地保护的长效机制。 相似文献
12.
曹礼 《安阳师范学院学报》2021,(2):100-106
基于验证增强式训练提升篮球运动员体能及竞技表现功效,探索提高大学生球员弹跳、灵敏、动态平衡能力的新方法的研究目的。该研究采用文献资料法、实验测试法、数理统计法等研究方法,以绍兴文理学院28名校篮球队员作为研究样本,针对2019-2020年度浙江省ZUBA大学生篮球联赛赛前体能训练予以增强式训练。通过对实验前后以跳跃触墙高度、T型测试时间、八向稳定限度等跳跃、灵敏、动态平衡能力运动评估指标的分析。研究发现:1)增强式训练能够有效增加大学生篮球选手的垂直跳跃高度、缩短T型测试时间,增强式训练的频率、时间及强度是影响PT提高垂直跳跃高度的首要因素,其组合方式、设置顺序及对象特征等因素也会影响其它训练效益。2)增强式训练能改善人体姿势平衡控制与神经肌肉适应,其在整体、右方、左前与左后等方向的LOS测试表现,即身体双侧姿势控制及动态平衡能力等方面,应激机制与PT包含姿势控制与快速敏捷性转向动作(急停、冲刺与方向变化)有关。研究显示增强式训练能够有效提高大学生篮球运动员动态平衡与弹跳能力,可作为赛前体能专项训练方法。 相似文献
13.
祝长生 《浙江大学学报(A卷英文版)》2003,4(5)
A disc-type magneto-rheological fluid damper operating in shear mode is proposed in this paper, which is based on the special characteristics of the magneto-rheological (MR) fluid with rapid, reversible and dramatic change in its rheological properties by the application of an external magnetic field. The magnetic field of the disc-type MR fluid damper is analysed by the finite element method; the controllability of the disc-type MR fluid damper on the dynamic behaviour of a rotor system; and the effectiveness of the disc-type MR fluid damper in controlling the vibration of a rotor system, are studied in a flexible rotor system with an over-hung disc. It is shown that the magnetic flux density of the disc-type MR fluid damper in the working areas can significantly change with the applied current in the coil; and that the dynamic behavior of the disc-type MR fluid damper can be varied by the application of an external magnetic field produced by a low voltage electromagnetic coil. The disc-type MR fluid damper can significantly change the dynamic characteristics of a rotor system, provided that the location of the disk-type MR fluid damper is carefully chosen. The disc-type MR fluid damper is a new actuator with good dynamic characteristics for rotating machinery. 相似文献
14.
In this study a new dynamic model of a rotor system is established based on the Hamilton principle and the finite element method (FEM). We analyze the dynamic behavior of the rotor system with the coupled effects of the nonlinear oil film force, the nonlinear seal force, and the mass eccentricity of the disk. The equations of the motion are solved effectively using the fourth order Runge-Kutta method in MATLAB. The dynamic behavior of the system is illustrated by bifurcation diagrams, largest Lyapunov exponents, phase trajectory diagrams, and Poincaré maps. The numerical results show that the rotational speed of the rotor, the pressure drop in the seal, the seal length, the seal clearance, and the mass eccentricity of the disk are the key parameters that significantly affect the dynamic characteristics of the rotor system. The motion of the rotor system exhibits complex types of periodic, quasi-periodic, double-periodic, multi-periodic, and chaotic vibrations. This analysis can be used to guide the design of seal parameters and to diagnose the vibration of rotor/bearing/seal systems. 相似文献
15.
INTRODUCTIONElectro rheological (ER ) Magneto rheologi cal(MR)fluidisakindofcontrollablefluidwhoserheologicalproperties,especiallyapparentviscosity,canbedramaticallyandreversiblyvariedinafewmillisecondsbytheapplicationofanexternalelectrical magneticfield… 相似文献
16.
Zhu Chang-sheng 《浙江大学学报(A卷英文版)》2003,4(5):514-519
A disc-type magneto-rheological fluid damper operating in shear mode is proposed in this paper, which is based on the special
characteristics of the magneto-rheological (MR) fluid with rapid, reversible and dramatic change in its rheological properties
by the application of an external magnetic field. The magnetic field of the disc-type MR fluid damper is analysed by the finite
element method; the controllability of the disc-type MR fluid damper on the dynamic behaviour of a rotor system; and the effectiveness
of the disc-type MR fluid damper in controlling the vibration of a rotor system, are studied in a flexible rotor system with
an overhung disc. it is shown that the magnetic flux density of the disc-type MR fluid damper in the working areas can significantly
change with the applied current in the coil; and that the dynamic behavior of the disc-type MR fluid damper can be varied
by the application of an external magnetic field produced by a low voltage electromagnetic coil. The disc-type MR fluid damper
can significantly change the dynamic characteristics of a rotor system, provided that the location of the disk-type MR fluid
damper is carefully chosen. The disc-type MR fluid damper is a new actuator with good dynamic characteristics for rotating
machinery.
Project supported partially by the EC BRITE/EURAM program under BRPR-CT97-0544 IMPACT project and State Key Laboratory of
Vibration, Shock and Noise, Shanghai Jiatong University 相似文献
17.
从三自由度超声波电机的原理与基本结构出发,先分析转子在静止情况下的力矩,接着分析转子在旋转情况下的力矩．随后通过转子转动时动平衡关系得到了求解摩擦驱动力矩和摩擦阻力矩的方法．最后,通过仿真结果对本文提出的数学模型做了初步验证,得到了一些有益的结果． 相似文献
18.
风机转子磁悬浮演示实验系统设计 总被引：1，自引：0，他引：1
开展风机转子磁悬浮演示实验系统设计,对学生充分了解和掌握机械的基本结构、工作原理、控制方式及其维护修理技术具有重要的意义,并在教学实践和科学研究等方面发挥了重要作用,为提高机械工程专业课程和课程实验等实践性教学环节的教学质量奠定重要基础,对促进教学改革有示范性。此外,学生在系统的设计分析过程中,能力得到了显著提高。 相似文献
19.
Recently, the finite element method (FEM) has been commonly applied in the engineering analysis of rotor dynamics. Gyroscopic moments, rotary inertia, transverse shear deformation and gravity can be included in computational models of rotor-bearing systems. In this paper, a finite element model and its solution method are presented for the calculation of the dynamics of dual rotor systems. A typical structure with two rotor shafts is discussed and the procedure for obtaining the coupling motion equations of the subsystems is illustrated. A computer program is developed to solve critical speeds and to simulate the transient motion. The influence of gyroscopic moments on co-rotation and counter-rotation is analyzed, and the effect of the speed ratio on critical speed is studied. The dynamic characteristics under different conditions of increasing speed during start-up are demonstrated by comparison with transient nodal displacements. The presented model provides a complete foundation for further investigation of the dynamics of dual rotor systems. 相似文献