角条件

The results show that the driving force angle and the pressure angle are complementary angle each other,i.e.α+δ=90°,the condition for pure rolling without sliding of toggle plate is δ≤φ and independen...

结果表明，传力角与压力角互为余角，即α+δ=90°，肘板机构纯滚动而无滑动的条件是δ≤φ，保证肘板纯滚动而无滑动的条件与肘板的摆角无关。

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。

Since theparabolic system is an approximation from the elliptic system under small ray angle,we may have reasons to question the result of the parabolic system under large rayangle.

由于抛物方程是椭圆方程在小掠射角条件下的近似，我们有理由对抛物系统在大掠射角情况下的考察结果的可靠程度保持怀疑。

Slender body is a widely used forebody configuration for modern advanced fighters and tactic missiles.

现代先进战斗机和战木导弹常具有细长前体，大攻角条件下前体背风面会形成非对称涡结构，从而产生很大的侧向力和偏航力矩，这会严重影。。。

A detailed investigation was conducted in this paper on the flow asymmetry and its influencing factors over an ogive slender body model, incorporated with surface pressure measurement, skin oil flow pattern visualization, hot wire dynamic signal acquasition and other relevant approaches, in a low turbulence wind tunnel.

现代先进战斗机和战木导弹常具有细长前体，大攻角条件下前体背风面会形成非对称涡结构，从而产生很大的侧向力和偏航力矩，这会严重影响飞行器的可操纵性和飞行安全。

Under different cut-angle circumstances the optical path differences with different incident angles i is calculated accurately and completely.

在不同切割角条件下，对光程差与入射角的关系进行了计算机模拟。

Pass to count to Wisterch parameter , and the steel wire is different from the molding tool get in touch with the length, and settle the path the research taking the length work the stabber angle to get under differently pull to stir the term, mold core adoption of best severally why size, combine the best work stabber of research the Cape, and settle the path to take the length nextly steel wire is in the molding tool of have fever to measure, air inside dispel-heat calories, winding dispel-heat on the coil-canister , and its molding tool dispel-heat calories of, and cause the steel wire the temperature difference pass in and outing the molding tool to influence steel wire machine function, under the experiment inside pull to stir the term according to the same race different work stabber Cape half of adoption the Cape(7 degree,10 degree,12 degrees, the best mold Cape, experience mold Cape) settle the path to take the length(2-3 mm,3-4 mm,4-5 mms, theories length, experience length) to proceed to experiment, and get the conclusion, work stabber the Cape then is more big the steel wire get in touch with the length with

通过对Wisterch参数，钢丝与模具接触长度、定径带长度、工作锥角度的研究得到了在不同拉拨条件下模芯采用的最佳几何尺寸，并研究最佳工作锥角、定径带长度下钢丝在模具中的发热量、空气中散热量、卷筒上的散热量及其模具散热量的不同，导致钢丝进出模具的温度差别对钢丝机械性能的影响，在实验中根据同种拉拨条件下采用不同工作锥角半角、定径带长度进行试验，得出结论，工作锥角越大则钢丝与模具接触长度越短，钢丝变形越剧烈，在模具中发热量就越高，导致钢丝出模温度高，使钢丝强度、硬度升高，弯曲、扭转次数降低，并且降低模具使用寿命。在其它条件相同的情况下，定径带越长则钢丝与定径带简壁磨擦增大，使钢丝发热量加大，从而使钢丝强度、硬度略升高，弯曲扭转次数略降低但定径带的增大减小了钢丝变形产生的弹性后效使钢丝出模直径比较稳定。

Subsonic vortical flows over a slender body at different angles of attack were simulated numerically,and the aerodynamic characteristics of asymmetric vortical flow were also investigated.

运用数值方法模拟了细长体在不同攻角条件下亚音速绕流的背涡结构，探讨了非对称涡流的气动力特性。

For the problem of the ratio of inner to outer diameter of long tube, according to the "residual core" in the target plays an important role in DOP of long tube penetrator, the analytical model of long tube pentration in semi-infinite homogeneous steel target is established and calculated to devide three kinds of different scopes, the rule of varied by the ratio of inner to outer diameter is analyzed. The patterns of penetration of the yawed tubular against a normal homogeneous semi-infinite target is established, the size and direction of "residual core" is analyzed, under the different impact yawed, the regularity of variations in the yawed of the tube and depth of the penetrateion is described during the penetrateion against the plate.

二是对于长管体的不同内外径比，依据长管体时形成的中间&靶芯&是其侵彻机理不同于长杆体的重要因素，分三种情况建立了长管体对半无限均质靶板的简化理论模型，并进行了分析，得出了穿深随内外径比变化的规律；描述了带攻角长管体垂直侵彻半无限厚靶的物理图像，分析了&靶芯&力的大小和方向，建立了侵彻简化模型，给出了在不同的初始攻角条件下，管体在侵彻过程中攻角和穿深的变化规律。

In different conditions on fluidized state and stability of conical fluidized bed. The conlusions are: the conical angel of the conical fluidized bed is 20°, the fluidized state havesmall difference in conical distributor and distributor plate. The angle of conical bed increase,the fluidized state will have big difference. The angle is 60°and the conical as distributor, themass of fluidized is less, the most of material is the bottom of conical bed. The effect ofdistributor plate is much better than the conical distributor. Sawdust and rice hull can fluidize.The annular gap of conical distributor different, the angle of conical bed is same, the fluidizedquality of 10mm annular gap is better than the other conical distributors. The annular gap ismore wide, the conical bed have more slugging phenomenon and the pressure fluctuate is turnbig.In the experiment the flow of 2％and 4％distributor plates don\'t easy to control, becausethe pressure is very big and the pressure fluctuate of conical bed is too big.

在不同的条件下对锥形床的流化状态和稳定性进行了研究，结果得出：锥形床的锥角为20度时，分布锥和分布板的流化状态相差不明显，随着锥形床锥角的增大，分布锥和分布板的流化现象会出现明显的变化，锥形床锥角越大，分布锥的流化状态变化越明显，流化的的物料越少，大量物料都聚集在锥形床底部，而分布板在加料量少的情况下，能流化起来。10mm、15mm和20mm环隙分布锥在锥形床锥角相同条件下，10mm环隙分布锥的流化质量要好于其它两个分布锥，环隙越大越容易出现腾涌现象的产生，压降波动范围增大。2％、4％和6％开孔率分布板在本实验测定时，2％和4％开孔率分布板的流量不容易调节，同时产生的压降波动范围也很大，比较来说，6％开孔率分布板流化质量好些。

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。