轴向的

The effect of tribology factors on bearing vibration is studied experimentally. AR model and WPT are used to processing the normal arid abnormal signals. The results are as follows:1. The vibration of ball bearings is caused by the tribology action of contact pairs of ball and ring races and has the essential of tribo-dynamics. Any factors affecting the tribology characteristics of contact pairs will affect vibration and noise of bearings consequently.2. Vibration characteristics of bearing keep almostly unchanged with the increasing of axial load expecting the increasing of nature frequencies. When radial load increasing with axial load unchanged, nature frequencies keep unchanged but some new vibration peaks appears in the spectrum.3. Vibration amplitudes are damped and nature frequency are enhanced with sufficient lubrication. Vibration and noise of bearings increase obviously and roar can happen and the contact surfaces scratch slightly under insufficient and unclean lubrication state. Bearing will be disabled in a few minutes without any lubrication.4. Bearing vibration is unstable under low speed. With the speed increasing, the vibration become stable and natural frequencies increase slightly but the amplitudes increase apparently.5. Bearing vibration can be excited only by some harmonics ofwaviness without lubrication and by all harmonics with lubrication based on the theoretical analysis.6. The nature frequencies of ball bearings decrease with the increasing sizes. When international clearance increasing, nature frequencies decrease in radial and increase in axial and angular and the amplitudes increase in radial and decrease in axial and angular. When the number of balls increasing, nature frequencies increase and amplitudes decrease. When the pitch diameter increasing, axial nature frequency increase and others nearly keep no change. When outer race groove curvature radius increasing, nature frequencies increase in radial and decrease in axial and angular and amplitudes keep no change in radial and increase in axial and angular. When inner race groove curvature radius increasing, nature frequencies decrease and amplitudes increase.7. The distortion in amplitude and frequency components of bearing vibration signals picked up by the present probe measurement method is founded and right conclusions cannot be achieved by the signals. When accelerometer is rigidly screwed with steel stud onto a flat outer surface of a ball bearing, vibration signal can be got without distortion and the reliability of research on bearing vibration is assured.8. AR model is suitable for large samples of bearing vibration signals, square root of length of samples can be used as the upper limitation of order determination and the FPE order selection criterion is effective. Many advantages of AR spectrum are founded over the classical based on FFT.9. Time-Frequency analysis is necessary for abnormal noise of ball bearings. WPT overcomes the principle shortcomings of STFT and proved to be a best tool to process the abnormal signals.

理论分析和试验研究表明： 1球轴承振动是钢球—滚道接触副中的各种摩擦学作用引起的，具有摩擦动力学的本质，任何对接触副的摩擦学特性有影响的因素都将对球轴承的振动和噪声特性产生影响； 2中心轴向载荷作用下，载荷增大使球轴承的固有振动频率升高，载荷越大同样的载荷增幅引起的频率升幅减小，足够大的中心轴向载荷作用下载荷的变化对球轴承振动的频率特性不会产生明显的影响； 3轴向和径向联合载荷作用下，径向载荷不大时球轴承振动的固有频率基本不变，但是可能引起变刚度激励的非线性振动，出现新的频峰，过大的径向载荷将使部分钢球脱离接触，使球轴承的振动和噪声呈现不稳定状态； 4润滑对球轴承的振动和噪声特性有重要的影响，良好的润滑对振动有明显的抑制作用，润滑不充分时，振动和噪声的水平会有明显增高，一定条件下还会激发接触副中的谐振，发出啸声，造成接触表面的伤害，无润滑干接触时，短时的运转就会损伤接触副表面，使振动和噪声迅速增大，并随时可能引发严重的磨损和卡滞失效；接触副润滑良好时，油膜的"刚化效应"使球轴承振动的固有频率有所提高，润滑剂中含有弥散性污浊时，振动的幅度总体升高，但弥散性污浊不会改变球轴承振动的频率特性；浙江大学博士学位论文：球轴承振动的研究 5低速时，球轴承振动的基本特征呈现不稳定状态，随着转速的提高，球轴承振动的频率特性趋于稳定，固有频率频峰升高； 6理论分析表明，干接触时钢球和滚道表面波纹度的某些谐波分量能激励球轴承的振动，振动的幅值与谐波幅值成正比，实际球轴承中钢球的分布不可能完全均匀，波纹度的激励作用会随时发生；润滑接触的分析表明，波纹度的任意谐波分量均能激励球轴承的振动； 7球轴承的几何和结构参数分析表明，球轴承尺寸越大，径向、轴向和角振动的固有频率越低；钢球中心圆直径增大，球轴承的径向和轴向振动的固有频率基本不变，角振动的固有频率有所上升，振动的幅频特性基本不变；径向游隙加大使球轴承的径向振动固有频率降低，轴向和角振动的固有频率有所升高，径向振动幅频特性的幅值升高，而轴向和角向降低；钢球的数量增多使球轴承振动的固有频率上升，幅频特性的幅值下降，径向振动的幅值下降最为明显；外圈沟曲率半径系数增大使球轴承径向振动的固有频率升高，轴向和角振动的固有频率降低，径向幅频特性基本不变，轴向和角向幅频特性幅值升高；内圈沟曲率半径系数增大使径向、轴向和角振动固有频率均下降，振动幅频特性的幅值均有升高； 8试验对比表明，传感器采用探针式安装时，由于探针接触副接触特性的影响，钡(量得到的球轴承振动信号有失真，采用专门设计和制作的试验球轴承，以固定式安装加速度计，首次测量得到了球轴承振动的真实信号，通过对振动信号的分析，验证了球轴承振动的理论模型； 9)基于时间序列分析的AR模型适用于大样本球轴承振动信号的分析，以样本长度的均方根值作定阶上界，FPE做判阶准则，给出的AR谱光滑，频率分辨率高，是球轴承振动分析的简便而可靠的手段； 10以时频域分析的小波包变换分析球轴承异音信号能够比较好地定位和聚焦异音发生的时间，时间间隔，频率范围，同样是球轴承振动分析的可靠的手段，可用作球轴承故障诊断技术。

Polynomial fitting was used to map out the pressure distribution curve of numerica...

与通过试验数据计算出的结果相比，数值模拟计算出来的轴向力相对误差在9%以内，而经验公式计算的轴向力相对误差为14%，采用数值模拟方法计算轴向力具有更高的精度，对多级离心泵轴向力平衡的研究具有指导意义。

In chapter II, we calculate the binding energy of a quantum wire in the presence of a strong magnetic field along the wire axis by using the variational method and strong perturbation method.

在第二章中，我们用变分法和强相互作用方法计算了在一个沿着轴向的强磁场下的量子线的束缚能，讨论了束缚能随着量子线的半径，磁场和掺杂浓度的变化。

Based on the vehicle ride comfort performances, analyzes the relationship between suspension system and vehicle ride comfort performances. Carrying on dynamics simulation to the different entire vehicle model under the different operating mode, analyzes each axial acceleration change curve in the post-processing module, the use curve processing function, the computation always weighting acceleration mean square value, analysis the influence of suspension system to ride comfort performances, and obtains the suspension system optimization plan.

基于整车行驶平顺性，从理论上分析悬架系统与整车平顺性的关系，然后对不同整车模型在不同的工况下进行动力学仿真，在后处理模块中分析各轴向的加速度变化曲线，利用曲线处理功能，计算总的加权加速度均方值，分析悬架系统对平顺性的影响，并在此基础上得出悬架系统选型的优化方案。

Firstly, triaxial compression creep tests with mica-quartzose schist which is a kind of soft metamorphic rock with lots of schistosity surfaces were carried out on the rock servo-controlling rheology testing machine under the condition of the axial stress vertical to the direction of the schistosity surface.

首先，对片理发育的软弱变质岩—云母石英片岩，在轴向力与片理垂直的条件下，采用岩石全自动流变伺服仪进行了三轴压缩蠕变试验，对轴向蠕变和径向蠕变进行了对比分析，提出径向蠕变比轴向蠕变敏感，以径向蠕变长期强度作为长期强度更合理。

The B and Q bands, the characteristic bands of the two metalloporphyrins, undergo bathochromic shift in some of the Lewis basic solvents. The spectral changes are thought to be due to the axial coordination of these solvents with vanadium in VOTPP and nickel in NiTPP. After axia...

结果表明，金属卟啉可以和一些Lewis碱性溶剂发生轴向配位作用，其特征紫外可见吸收峰发生红移；轴向配位作用与卟啉中心金属离子的外层d轨道电子数、碱性溶剂的供电子能力及其空间构造有关，VOTPP比NiTPP更容易和Lewis碱性溶剂发生轴向配位作用；碱性强、空间阻碍小的Lewis碱性溶剂易于与金属卟啉发生轴向配位作用。

On base of analysis to simulation result, it was point out the main cause making dissimilar metal"s bonding so difficult was metal"s inharmonic plastic deformation. The distribution and changement of stress and strain on interface and in workpieces were analyzed.Making use of experiment and simulation result, main factors that influence welding property of cold pressure welding were discussed.

通过对模拟结果的分析，说明了异种金属冷压焊较同种金属冷压焊困难的原因主要是界面处两种材料的径向和轴向的不协调塑性变形；直观地显示了冷压焊过程中工件内部及界面处的应力应变分布及变化情况。

The thesis designs that PLC controls four servo electric motors using Aimosheng EC20H , the rocker arm realizing beam drill goes up and down , the rocker arm rotates , the main spindle box slides , the chief axis moves forward to give axial four action , PLCs the motion controlling one frequency conversion electric motor at the same time realizing the machine tool host moving the revolution being a chief axis.

本论文设计使用艾默生EC20H PLC控制四台伺服电机，实现摇臂钻床的摇臂升降、摇臂旋转、主轴箱滑动、主轴进给四个轴向的动作，PLC同时控制一台变频电机实现机床的主运动即主轴的旋转运动。

The Van der pol equation under impulse excitation can be used to simulate the development of perturbation along the body,and it can also explain the exponential growth of the disturbance energy.

采用脉冲激励的Van der pol方程可以很好地模拟扰动量沿轴向的发展过程，而且可以解释扰动能量的指数增长现象。

The plasma spraying technique was used to prepare a set of thermal barrier coating specimens,and water-cooling method was used in thermal shock experiments.

用等离子喷涂方法在合金圆柱体上制备了热障涂层，并用水冷的方法进行了热冲击实验，试样的失效现象为轴向的开裂和剥落。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。