ABAQUS子程序USDFLD.docx

1、ABAQUS子程序USDFLDAbaqus/CAE Users Manual12.8.5 Defining field variables at a material point个材料点岌义场雯量丿In Abaqus/Standard you can introduce dependence on solution variables with user subroutine USDFLD. This subroutine allows you to define field variables at a material point as functions of time, of any

2、of the available material point quantities listed in output variable identifiersj Section4.2of the Abdqus Analysis Users Manual, and of material directions. Material properties defined as functions of these field variables may, thus, be dependent on the solution.User subroutine USDFLD is called at e

3、ach point for which the material definition includes a referenee to the user subroutine(A. ABAQUS里面，你能够用子程序USDFLD来求解变量。USDFLD允许你将 一个材料6上的场雯量龙义为肘间场数，能够使用到的材料点亦用户使用手册 421节中“abaqus输岀变量的标识码”中彼提及到。材料的特性菠定义作场 雯量的函救，因此依赖于求解方比。丿(柱每个被定义材抖性能的6 USDFLD能够後调用丿To include a reference to user subroutine USDFLD in a

4、material definition：1.From the menu bar in the Edit Material dialog box. select General User Defined Field.(For information on displaying the Edit Material dialog box. seeCreating or editing 8 materiaj Section 12.7J2.Click OK to close the Edit Material dialog box. Alternatively, you can select anoth

5、er material behavior to define from the menus in the Edit Material dialog box (see “Browsing and modifying material behavior* Section 12.72 for more information).Abaqus/CAE Users Manual W W（孑程序USDFLD蛊材料中的龙义it程可洪考下面：1.疫编辑材料的对话框中选择General- User Defined Field2.AOK关闵编辑材坍的对话框，或者A编辑对话桓中选择另外的一个材料特性。）Abaqus

6、 User Subroutines Reference Manual1.L49 USDFLDUser subroutine to redefine field variables at a material point.（在一个材料6上使用USDFLD重新灾义场tf ）Product: Abaqus/StandardReferences C参考丿Obtaining material point information in an Abaqus/Standardanalysis/ Section 2.6Material data definition, Section 20.2 of the A

7、baqus Analysis UsersManual-USER DEFINED FIELDDamage and failure of a laminated composite plate/ Section 14 of the Abaqus Example Problems Manual“USDFLD,” Section 4.24 of the Abaqus Verification ManualOverview (机述丿User subroutine USDFLD:allows you to define field variables at a material point as func

8、tions of time or of any of the available material point quantities listed in the Output Variable Identifiers table ( Abaqus/Standard output variable identifiers/ Section 4.2of the Abaqus Analysis Users Manual) except the user-defined output variables UVARM and UVARM/7；can be used to introduce soluti

9、on-dependent material properties since such properties can easily be defined as functions of field variables;will be called at all material points of elements for which the material defi nition in eludes user-defi ned field variables;must call utility routine GETVRM to access material point data;can

10、 use and update state variables； andcan be used in conjunction with user subroutine UF1ELD to prescribe predefined field variables.(孑程序USDFLD：1.允许你4 一个材料点定义场变量作为肘间函数柱输出变量的标 示符中列出了所有材料点的雯量，除了用户定义的输出雯量 和 uvarm uvarmo2.能够用来介绍材抖的性能，并且这种性能能够菠龙义为场变量的3.柱各元素的材料点中，用户龙义的场雯量能够被调用。4.处须调用使用程序GETVRM来接入妨料点救据5.可以和U

11、FIELD 起使用来福述预岌义的场变量丿Explicit solution dependence （朗确鮮的关糸）Since this routine provides access to material point quantities only at the start of the in creme nt, the solution depende nee introduced in this way is explicit: the material properties for a give n increme nt are not influenced by the result

12、s obtained during the in creme nt. Hence, the accuracy of the results depends on the size of the time increment. Therefore, you can control the time in creme nt in this routine by means of the variable PNEWDT.（由于程序提供的接入点只是柱增量的开始，解之间的相互关糸应该彼刚确：在 增量的过程中，妨料的性能不应该祓得列的结果所影响。因此，结果的准确性依 赖于肘间增量的丸小。因此，你能通过PE

13、NWDT来抄制程序中的肘间增量。）Defining field variables义场变量）Before user subroutine USDFLD is called, the values of the field variables at the material point are calculated by interpolation from the values defined at the nodes. Any changes to the field variables in the user subroutine are local to the material poi

14、nt: the no dal field variables retain the values defined as initial conditions, predefined field variables, or in user subroutine UFIELD. The values of the field variables defined in this routine are used to calculate values of material properties that are defined to depend on field variables and ar

15、e passed into other user subroutines that are called at the material point, such as the following：CA-f程序USDFLD拔调用之前，通过节点中龙义的数值采用麦值法计算出材 料点的场雯量。子程序中场变量的任意改动都是柱材料点上的改动：节点场雯量 保特着数值彼岌义为初始状态（预岌义场变量丿，或者使用子程序UFIELD.程序 中场变量的值被用来计算材料的性能，材料的特性彼龙义依赖于场变量，并且亦 其他孑程存中彼调用。例如下面的程存：丿CREEPHETVALUEXPANUHARDUHYPELUMATUM

16、ATHTUTRSOutput of the user-defined field variables at the material points can be obtained with the element integration point output variable FV (see Abaqus/Standard output variable identifiers/* Section 4.2.1 of the Abaqus Analysis Users Manual).Accessing material point data (it 料存舖点数据)You are provided with access t