摩擦

Next, a few important friction models in common use are discussed, including six static and seven dynamic friction models. The forms, characteristics and applicability of these models are discussed in detail.

其次， 系统地介绍了几种较为重要的、常用的摩擦模型，包括6种静态摩擦模型和7种动态摩擦模型，并对每一种模型的构成，特点和适用范围等进行了较为详细地论述。

At present, although finite element methods is a kind of effective measures in analyzing metal plastically forming problems with friction, dynamic friction in the process of metal forming is substituted with static friction and constant frictional force as one of independent constraint conditions is transposed to equivalent node-load or FEM unit is divided into contact unit and inner unit in numerous studys and applications, so that it result in relative bad accuracy and awkward operation. These defects mostly attribute to the fact that FEM bases on the variational equality principles, however frictional constraint will actually result in variational inequality energy functional.

目前，应用于分析金属塑性成形的有限元法是一种有效的处理摩擦效应的定量计算方法，但是许多应用和研究是用常摩擦来代替金属塑性成形过程中的动态摩擦；把常摩擦力作为单独的约束条件移置到等效结点载荷上或把有限元单元划分成接触单元和内单元，这些将导致解的精度相对不高及实际操作不方便等一系列问题，产生这些不足的重要原因之一在于它的理论基础是变分等式原理。

In the analysis, firstly, the flux boundary condition is used to simulate the frictional heat resource between wheel and rail. The non-steady heat transfer between the contacting surfaces of the wheel/rail, heat-convection and radiation between the wheel/rail and the ambient were all taken into consideration. Therefore, a heat coupling model of the wheel/rail in rolling/sliding is put forward to calculate the frictional temperature rise in the wheel and rail. Secondly, after the temperature distribution of wheel/rail, due to friction, is calculated, substitute the thermal load with equivalent fictitious body force and boundary distributed force loaded on the nodes of the corresponding elements. The wheel-load is applied to the center of the wheel.

首先，用热流边界条件模拟轮轨接触界面的摩擦热源，考虑轮轨间的非稳态热传导、轮轨自由表面与环境的热对流、热辐射的影响，建立轮轨滚动接触热耦合有限元计算模型，分析计算轮轨滚、滑工况下的摩擦温升；其次，以求得的轮轨温度场结果作为求解轮轨应力场的已知条件，轮载以集中力形式直接加载于轮心处，将摩擦温升引起的热载荷等效为假想体力和热边界面力，施加于相应的单元节点上，建立了轮轨热—机械载荷耦合作用的热弹性平面应力模型，分析热—机械载荷作用下的轮轨应力场。

It is a new type of excellent automobile friction brake material as a replacement of asbestos friction materials

研究表明：此摩擦材料力学性能高，摩擦性能稳定，特别是高温磨损小，噪声低，是一种取代石棉摩擦材料的新型制动材料。

The correlation test on pressure, speed and temperature of brake friction coefficient are performed, the results indicate that the stability of friction coefficient is enough.

按照制动标准VW TL 110规定的试验程序，进行了制动衬片摩擦系数的压力、速度、温度相关性试验，试验结果表明，制动摩擦系数随压力、速度、温度的变化范围在规定的离散带范围内，摩擦系数的稳定性是符合要求的。

Friction rubber draft gear, as one of high-capacity draft gears, is developed after friction steel spring draft gear. Rubber has energy absorption capability and non-linear rigidity capability, so the friction rubber draft gear's capacity is usually higher than the friction steel spring bumper.

摩擦式橡胶缓冲器是继摩擦式钢簧缓冲器之后开发的一种大容量缓冲器，这种缓冲器利用了橡胶自身具有吸收能量及非线性刚度的特性，因此其容量一般比摩擦式钢弹簧缓冲器高。

We can reduce friction where it is undesirable, and increase it where it is needed.

我们可以在不需要摩擦的地方减少摩擦，在需要的地方增加摩擦。

The effect of surface friction on the structure of front and frontogenesis is investigated by using the cloud model in which the large-scale deformation field is taken into consideration.

利用加入大尺度变形场作用的非静力模式，研究了地面摩擦对锋生和锋面结构的影响，在变形场锋生条件下，对不同模式格距、不同湍流参数化方案、不同变形场强度、考虑与不考虑地面摩擦等情形进行了比较，在考虑地面摩擦拖曳作用后得到了类似重力流结构的边界层锋面特征。

The stiffness, stress distribution and contact status under different friction coefficients were obtained, and the influence of interleaf friction coefficient on the stiffness and stress was studied.

在不考虑摩擦和考虑摩擦两种情况下计算其刚度、应力分布和接触情况，研究片间摩擦对钢板弹簧刚度和应力的影响。

And more, the article dissects the friction of the joggle, notarizes that the character of the friction is mixed friction which is near boundary friction, and get a conclusion that the rolling part of friction can be neglect through a c...

继而对该处的摩擦问题进行剖析，确认滑动性质为接近边界摩擦的混合摩擦，并且通过一个实例计算得出滚动摩擦部分可忽略不计的结论。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。