1、冲压模具设计外文翻译 摘录: 在这一篇论文中,对滚动接触机械装置上的滚动接触体结构柔性变形的效果简短地分析。轮副和轨道对轮的潜变力的结构变形的效果和轨条详细地被分析研究。轮副的一般结构柔性变形和轨道首先分别用有限元的机械要素方法和关系一起分析 ,从而获得表达滚动方向和轮副的横方向的结构柔性变形和对应的负载。按照它们之间的关系 ,我们计算轮和轨条的在一点相接接触的影响力系数。影响力系数代表发生在轮 /轨道接触的一个小的矩形面积上的单位面积的牵引力引起的结构柔性变形。他们习惯校订一些与 Kalker 的无赫兹的形状滚动接触的三维空间的有柔性体的理论 Bossinesq 和 Cerruti 的公式一
2、起获得的影响力系数。在潜变力的分析中 , 利用了修正的 Kalker 的理论。从轮副和轨道的结构柔性变形中获得的数字结果表明潜变力发挥的很大影响力。 2002 Elsevier 科学出版社版权所有。 关键字 : 轮 /轨条 ; 滚动接触 ;潜变力 ;柔性变形结构 1.介绍 由于火车轮副和轨道之间的很大相对运动作用力引起轮副和轨道的结构较大的柔性变形。大的结构变形极大影轮和轨条响滚动接触的性能 ,如潜变力,波形 1 3 ,黏着,滚动接触疲劳 , 噪音 4,5 和脱轨 6等等 . 到现在为止在轮 / 轨道的潜变力的分析中广泛应用的滚动接触理论是以柔性一半的空间假定为基础的 7 12. 换句话说,轮
3、 / 轨道的一个接触的柔性变形和牵引之间的关系可以用 Bossinesq和 Cerruti的理论公式表达。实际 , 当轮副在轨道上持续运动 ,接触的柔性变形是比那些以滚动接触的现在理论公式计算的更大。因为轮副 / 轨道的挠性是比柔性一半的空间更加大 。由对应的负荷所引起的轮副 / 轨道柔性变形结构在图中被显示。如 1 和 2. 在图中轮副弯曲变形被显示出来。在图 1a 中被显示的轮副弯曲 变形主要由车辆和轮副 /轨条的垂直动载荷所引起。在图 1 b 中描述的轮副扭转的变形是由于轮和轨道之间的纵潜变力的作用生产的。在图 1 c 中显示的轮副斜角弯曲变形和在图 2 中显示的轨道翻折变形主要地由交通
4、工具和轮副 /轨道的横动态负荷所引起。在轮副 (图 1 d) 的轴周围的和旋转装置相同方向的扭转变形 ,火车可以使用的 ,主要在电动机的轮 / 轨条和驱动扭矩的接触补缀上的牵引所引起。到目前为止很少的出版物讨论滚动接触的轮副和轨道之间的爬动和潜变力的效果。 事实上,上面提到轮副 / 轨道的柔性变形结构是在轮 /轨道 的常态和切线的接触刚性以下运动。轮 / 轨道的正常的接触点的刚性通常低于轨道的下沉位置。 低于正常接触点的刚性很少的影响接触面积上的正常压力。那低于切线的接触刚性很大影响接触面积的黏结 / 滑移面积状态和牵引力。如果滚动接触的柔性变形结构的影响被对于轮 /轨道的分析考虑进去,一对接
5、触面积的全体微粒滑移与用现在滚动接触理论计算的结果不同。所有的连络颗粒和摩擦功的总的滑移比那在分析轮 /轨道浅动力的时候,被忽略的柔性变形结构更小。同样一个接触面积的根 / 转差面积的比率比没有考虑的柔性变形结构的效果更大。在这一篇论文中,在滚动接触性能上的滚动接触的车体柔性变形机构的装置被简短地分析,而且和Kalkers 无赫兹的形状滚动接触的三度空间的有柔性车体的理论模型用来分析在轮副和轨道之间的潜变力。在数值分析中挑选的轮副和轨条分别地 ,是货车轮副的锥形轮廓,中国 兆位元组 和钢轨条的质量是 60 公斤 /m 。有限元分析方法用来决定他们的柔性变形结构。依照柔性变形结构的关系和对应的由
6、于 FEM 获得负荷 , 表示轮副的柔性变位的影响系数是由轮 / 轨条的接触单位面积密度有所反应的牵引生产的轨条所决定。这些影响系数用来代替一些与Kalkers 的理论 Bossinesq和 Cerruti的公式一起计算的影响系数。在图 1a 中被显示的轮副弯曲变形的效果和在轮副轨道的柔性变形结构之中的横断的影响力在研究中被疏忽。获得的数字结果表明在轮副 /轨道柔性变形结构的潜变力效果考虑和疏忽的条件之间的显着差别。 In this paper the mechanism ofeffects of structure elastic deformations of bodies in roll
7、ing contact onrolling contact performance is briefly analyzed. Effects of structuredeformations of wheelset and track on the creep forces of wheel and rail are investigatedin detail. General structure elastic deformations of wheelset and track arepreviously analyzed with finite element method, and t
8、he relations, whichexpress the structure elastic deformations and the corresponding loads in therolling direction and the lateral direction of wheelset, respectively, areobtained. Using the relations, we calculate the influence coefficients oftangent contact of wheel and rail. The influence coeffici
9、ents stand for theoccurring of the structure elastic deformations due to the traction of unitdensity on a small rectangular area in thecontact area of wheel/rail. They areused to revise some of the influence coefficients obtained with the formula ofBossinesq and Cerruti in Kalkers theory of three -d
10、imensional elastic bodies inrolling contact with non-Hertzian form. In the analysis of the creep forces,the modified theory of Kalker is employed. The numerical results obtained showa great influence exerted by structure elastic deformations of wheelsetandtrack upon the creep forces. 2002 Elsevier S
11、cience B.V. Allrights reserved. Keywords:Wheel/rail; Rolling contact; Creep force; Structureelastic deformation 1.Introduction During running of a train on track the fierce action between wheelsetandrails causes large elastic deformations of structure of wheelset and track. Thelarge structure deform
12、ations greatly affect performances of wheels and rails inrolling contact, such as creep forces, corrugation 1 3, adhesion, rollingcontact fatigue, noise 4,5 and derailment 6. So far rolling contacttheories widely used in the analysis of creep forces of wheel/rail are based onan assumption of elastic
13、 half space 7 12. In other words, the relationsbetween the elastic deformations and the traction in a contact patch ofwheel/rail can be expressed with the formula of Bossinesq and Cerruti in thetheories. In practice, when a wheelset is moving on track, the elasticdeformations in the contact patch ar
14、e larger than those calculated with thepresent theories of rolling contact. It is because the flexibility ofwheelset/rail is much larger than that of elastic half space. Structure elasticdeformations (SED) of wheelset/rail caused by the corresponding loads are shownin Figs. 1 and 2. The bending defo
15、rmation of wheelset shown in Fig. 1a ismainly caused by vertical dynamic loads of vehicle and wheelset/rail.Thetorsional deformation of wheelset described in Fig. 1b is produced due to theaction of longitudinal creep forces between wheels and rails. The obliquebending deformation of wheelset shown i
16、n Fig. 1c and the turnover deformationof rail shown in Fig. 2 are mainly caused by lateral dynamic loads of vehicleandwheelset/rail. The torsional deformations with the same direction ofrotation around the axle of wheelset (see Fig. 1d), available for locomotive,are mainly caused by traction on the
17、contact patch of wheel/rail and drivingtorque of motor. Up to now very few published papers have discussions on theeffects of the SED on creepages and creep forces between wheelset and track inrolling contact. In fact, the SED of wheelset/railmentioned above runs low the normal and tangential contac
18、t stiffness ofwheel/rail. The normal contact stiffness of wheel/rail is mainly lowed by thesubsidence of track. The normal contact stiffness lowed doesnt affect thenormal pressure on the contact area much. The lowed tangential contactstiffness affects the status of stick/slip areas and the traction
19、in thecontact area greatly. If the effects of the SED on the rolling contact aretaken into account in analysis of rolling contact of wheel/rail, the total slipof a pair of contacting particles in a contact area is different from thatcalculated with the present rolling contact theories. The total slip of all thecontacting particles and the friction work are smaller than those obtainedunder