22.1.4 - Frictional - behavior -- 摩擦行为

1、22.1.4 - frictional - behavior - - 摩擦行为 abaqus analysis users manual 22.1.4 frictional behavior 摩擦行为 products: abaqus/standard abaqus/explicit abaqus/cae references ? ? ? ? ? ? “mechanical contact properties: overview,” section 22.1.1 “fric,” section 25.2.8 “vfric,” section 25.3.2 *friction *change

2、friction “creating interaction properties,” section 15.11.2 of the abaqus/cae users manual overview when surfaces are in contact they usually transmit shear as well as normal forces across their interface. there is generally a relationship between these two force components. the relationship, known

3、as the friction between the contacting bodies, is usually expressed in terms of the stresses at the interface of the bodies. the friction models available in abaqus: 当发生接触时，表面通常通过接触面传播剪力和法向力。这两种力之间一般有关系。该关系也叫接触体间的摩擦，它一般表达为物体接触面应力的形式。在abaqus中的摩擦模型： include the classical isotropic coulomb friction mod

4、el (see “coulomb friction,” section 5.2.3 of the abaqus theory manual), which in abaqus: ? 包括经典的各向同性库仑摩擦模型（见“coulomb friction,” section 5.2.3 of the abaqus theory manual），该模型在abaqus中： ? ? in its general form allows the friction coefficient to be defined in terms of slip rate, contact pressure, avera

5、ge surface temperature at the contact point, and field variables; and ? 普通式允许根据滑移率，接触压力，接触点的平均表面温度和场 变量定义摩擦系数； ? provides the option for you to define a static and a kinetic friction coefficient with a smooth transition zone defined by an exponential curve; ? 提供选项来定义静止和运动学的摩擦系数用由指数曲线定义的平 滑转换区； ? ? ?

6、 ? ? ? ? ? ? ? ? ? allow the introduction of a shear stress limit, , which is the maximum value of shear stress that can be carried by the interface before the surfaces begin to slide; 允许引入剪应力极限，该应力极限是接触面在开始滑动前所能承受的最大剪应力值； include an anisotropic extension of the basic coulomb friction model in abaqu

7、s/standard; 包括在abaqus/standard中对基本库仑摩擦模型的各向异性扩展； include a model that eliminates frictional slip when surfaces are in contact; 包括当表面接触时消除摩擦滑动的模型； include a “softened” interface model for sticking friction in abaqus/explicit in which the shear stress is a function of elastic slip; 包括在abaqus/explicit中

8、针对粘着摩擦的软接触面模型，在粘着摩擦中剪应力是弹性滑动的函数； can be implemented with a stiffness (penalty) method, a kinematic method (in abaqus/explicit), or a lagrange multiplier method (in abaqus/standard), depending on the contact algorithm used; and 可用刚度（罚函数）法，运动学法（abaqus/explicit里）或者拉格朗日乘子法（abaqus/standard里）来实现，摩擦决于使用的算法

9、。 can be defined in user subroutine fric (in abaqus/standard) or vfric (in abaqus/explicit for the contact pair algorithm only), which allows modeling of very general frictional surface conditions. 可在用户子程序fric（abaqus/standard中）或vfric（abaqus/explicit中只用于接触对算法），用户子程序容许模拟非常一般的摩擦表面条件。 in abaqus/standard

10、 tangential damping forces can be introduced proportional to the relative tangential velocity, while in abaqus/explicit tangential damping forces can be introduced proportional to the rate of relative elastic slip between the contacting surfaces (see “contact damping,” section 22.1.3, for more infor

11、mation). 在abaqus/standard中能引入切向阻尼力，该力与切向相对速度成比例。在abaqus/explicit中能引入切向阻尼力，该力与接触表面间相对弹性滑移速率成比例（更多信息见“contact damping,” section 22.1.3）。 including friction properties in a contact property definition 在接触属性定义里包含摩擦属性 abaqus assumes by default that the interaction between contacting bodies is frictionles

12、s. you can include a friction model in a contact property definition for both surface-based contact and element-based contact. abaqus默定接触体间相互作用为无摩擦。你可以在基于面和基于单元的接触属性定义里包含摩擦模型 input file usage: use both of the following options for surface-based contact: *surface interaction, name=interaction_propert

13、y_name *friction use both of the following options for element-based contact in abaqus/standard: *interface or *gap, elset=name *friction abaqus/cae usage: interaction module: contact property editor: mechanicaltangential behavior element-based contact is not supported in abaqus/cae. changing fricti

14、on properties during an analysis 在分析过程中改变摩擦属性 the methods used to change friction properties during an analysis differ between abaqus/standard and abaqus/explicit. 在abaqus/standard and abaqus/explicit里在分析过程中改变摩擦属性的方法不同。 changing friction properties during an abaqus/standard analysis 在abaqus/standard

15、分析过程中改变摩擦属性 it is possible to remove, to modify, or to add a friction model to a contact property definition in any particular step of an abaqus/standard simulation. in some models, such as shrink-fit contact interference problems, friction should not be added until after the first steps have been c

16、ompleted. in other models friction might be removed or lowered to represent the introduction of a lubricant between the bodies. 在任何abaqus/standard仿真分析步里可以移除，修改或添加摩擦到接触属性定义里。某些模型，比如收缩配合接触过盈问题，直到第一步完成，才能添加摩擦。在另一些模型，为了表示在物体间引入润滑剂，应该移除或减小摩擦。 you must identify which contact property definition or contact

17、 element set is being changed. 你必须确定哪种接触属性定义或接触单元集改变了。 input file usage: use both of the following options for surface-based contact: *change friction, interaction=name *friction use both of the following options for element-based contact: *change friction, elset=name *friction abaqus/cae usage: def

18、ine a contact property with a new friction definition. then change the contact property assigned to an interaction in a particular step. interaction module: contact property editor: mechanicalbehavior interaction editor: contact interaction property: new_interaction_property_name element-based conta

19、ct is not supported in abaqus/cae. tangential specifying the time variation of the change in friction coefficients 指定改变摩擦系数的时间变化 you can use an amplitude curve (specifying a relative magnitude definition) to define the time variation of the change in friction coefficients throughout the step. 你能使用幅值

20、曲线（指定相对大小的定义）来定义摩擦系数随分析步时间的变化。 if the friction coefficient is dependent on slip rate, contact pressure, average surface temperature at the contact point, or field variables, the current change in the friction coefficient at a material point is defined as the difference between the friction coefficie

21、nt for the current slip rate, contact pressure, etc. and the friction coefficient at the end of the previous step, multiplied by the amplitude magnitude. 如果摩擦系数由滑移率，接触压力，接触点的平均表面温度或场变量决定，那么当前在材料点上改变摩擦系数定义为由当前滑移率，接触压力等决定的摩擦系数和上一分析步末的摩擦系数的差，再乘以幅值大小。 if you do not specify an amplitude curve, the change in friction coefficients is applied immediately at the beginning of the step or ramped up linearly over the step, depending on the amplitude variation assigned to the step (see “procedures: overview,” section 6.1.1). if the friction coefficients are changed from finite values to rough friction or