查询词典 friction

The key to this yield criterion is that the concept of internal friction angle which used in soil mechanics has been introduced to infer the relationships among poisson ratio, internal friction angle and relative density.

并且在Miss屈服准则的基础上论证了粉末体屈服准则在主应力空间，为一个回转椭球体。

Four-node degenerated shell element and rigid shell element are used in our FEM model.Updated Lagrange formulation and rate form constitutive equation are adopted to solve the problem of large strain and large rotation in sheet forming process.Sheet metal material property is described by plastic anisotropy yielding model and isotropic hardening model.Master surface-slave surface contact model is used to define the contact between tools and blank.Contact constraints are enforced with a kinematic algorithm and friction stress is computed by Coulomb friction law.Dynamic relaxation method is used to treat springback after forming stroke.

四结点蜕化壳单元和刚体壳单元分别用来建立板和模具的有限元模型；更新Lagrange法和速率型本构关系被用来处理板料变形中的大应变和大转动；材料模型采用塑性各向异性屈服与等向强化模型；通过主从面模型定义板料和模具的接触，接触算法采用运动约束法，摩擦力用库仓定律计算；并利用动力松弛法对回弹过程进行了计算。

In chapter six, A finite element model to evaluate the mechanics properties of thin wall structure is put forwards. The 4-node quadrilateral Hughes-Liu shell element with five through-the-thickness integration points is employed. The material is assumed to satisfy the elastic-plastic yield condition with isotropic hardening. The single surface contact algorithm is taken to deal with the contact searching. The priori stabilization procedures for the numerical control of the hourglass instability and the penalty method for the evaluation of contact force are used. The classical Coulomb law of friction is employed to evaluate the friction force.

第六章采用法向方向5点积分的4节点Hughes-Liu壳单元，前置参数法砂漏控制技术，等向强化弹塑性材料模型，分步增量应力回映方法，一体化接触搜寻算法，罚参数接触力计算方法及经典摩擦定律，建立了一种计算受冲薄壁结构大变形力学特性计算的有限元模型，通过对汽车A传动轴及汽车纵向方形吸能梁的大变形力学特性分析，验证了该有限元模型的正确性。

The results of tests of friction and wear shows that the coefficient of kinetic friction of specimens is decreased by 64%～77%,and the wear rate of specimens is decreased by 22%～48%.

精密摩擦、磨损试验及显微硬度测量结果，试件表面的滑动摩擦系数降低了64%～77%；磨损率减少了22%～48%；显微硬度提高0.3～1.4倍。

For sliding contact, the coefficient of kinetic friction Uk is defined as the ratio of the friction al force to the normal force

滑动接触时，动摩擦系数Uk的定义是摩擦力与法向力的比率。

"Kinetic friction arises between surfaces in relative motion, static friction acts between surfaces at rest with respect to each other"

动摩擦力存在于相对运动之表面间，静摩擦则存在于静止的表面间，。

K stands for the coefficient of kinetic friction and Fk stands for the Force due to the kinetic friction, m is the mass of the ball and g means gravity.

k主张系数的动力学摩擦的FK对于主张武力由于动力学摩擦， M是质量的球和G手段的严重性。

By making such effort, the conclusion has been drawn as follows: the redistribution of vertical force and transformation of coefficient of kinetic friction are the fundamental factors of ultra-low friction.

在具有构造等级的深部岩体介质的变形过程中，储能及返还性状与介质变形的摩擦因数有关。

ABSTRACT Linear Motion Guide is a new kind of rolling functional unit with the advantages of simple structure, small difference between static friction force and kinetic friction force, high setting accuracy andgood stability of high precision, etc..

滚动直线导轨副是新兴的滚动功能部件，具有结构简单、动静摩擦系数小、定位精度高、精度保持性好等优点。

The action point of limiting force on retaining structure is not always at 1/3 of the height of retaining structures, but varies with the friction angle δ between soil and retaining structures, the type of limiting state, the failure mode, the internal friction angle φ, and cohesion c of the soil, ranging from 1/5 to 2/3 of the height of retaining structures.

3土体极限荷载P〓的作用点位置不象Coulomb理论中假定的那样，总是作用在墙高的1／3处，而是与土体极限状态的类型、土体的破坏形式、墙土之间的摩擦角δ、土体的内摩擦角φ和粘聚力c有关系，在挡土结构物高度的1／5到2／3的范围内取值。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。