InAbaqusit is sometimes desirable to set up the runtime environment and manageinteractions with external data files or parallel processes that are used inconjunction with user subroutines. For example, there may be history-dependentquantities to be computed externally, once per increment, for use during theanalysis; or output quantities that are accumulated over multiple elements inCOMMON block variables within user subroutinesmay need to be written to external files at the end of a converged incrementfor postprocessing. Such operations can be performed with user subroutineinAbaqus/StandardandinAbaqus/Explicit.This user interface can potentially be used to exchange data with another code,allowing for “stagger” betweenAbaqusand another code.
Abaqus User Subroutines Global Coordinate Test
If problems are encountered during compilation or linking of the subroutine,make sure that theAbaqusenvironment file (the default location for this file is thesite subdirectory of theAbaqusinstallation) contains the correct compile and link commands as specified in.These commands should have been set up by theAbaqussite manager during installation. The number and type of arguments mustcorrespond to what is specified in the documentation. Mismatches in type ornumber of arguments may lead to platform-dependent linking or runtime errors. Your user subroutine will share memory resources withAbaqus.When you need to use large arrays or other large data structures, you shouldallocate their memory dynamically, so that memory is allocated from the heapand not the stack. Failure to dynamically allocate large arrays may result instack overflow errors and an abort of yourAbaqusanalysis. For an example of dynamic allocation using native Fortran allocatablearrays, refer to.Abaqusalso provides another, more convenient way for users to allocate their ownstorage (see). Although a local coordinate system can be defined for each part instance,all variables (such as current coordinates) are passed to a user subroutine inthe global coordinate system, not in a part-local coordinate system.
For example user subroutine UMAT in Abaqus/Standard and user subroutine VUMAT in Abaqus/Explicit allow constitutive. An ABAQUS toolbox for multiscale finite element. Apr 19, 2013 - the computation procedure in ABAQUS using a Python scripting and user-defined. Good accuracy the results obtained in 19. First, you need to define user defined material orientation for the composite and then use ORIENT sub-routine and link the FORTRAN program with the abaqus job. In FORTRAN subroutine, you must define the orientation of each elements as per your geometry. Once you have done this then check that whether orientation is defined correctly or not in ABAQUS Viewer.
The onlyexception to this rule is when the user subroutine interface specificallyindicates that a variable is in a user-defined local coordinate system (,or).The local coordinate system originally may have been defined relative to a partcoordinate system, but it was transformed according to the positioning datagiven for the part instance. As a result, a new local coordinate system wascreated relative to the assembly (global) coordinate system. This newcoordinate system definition is the one used for local orientations in usersubroutines. The node and element numbers passed to a user subroutine are internalnumbers generated byAbaqus.These numbers are global in nature; all internal node and element numbers areunique.
If the original number and the part instance name are required, callthe utility subroutine GETPARTINFO ( Abaqus/Standard)or VGETPARTINFO ( Abaqus/Explicit)from within your user subroutine (see).The expense of calling these routines is not trivial, so minimal use of them isrecommended.Another utility subroutine, GETINTERNAL ( Abaqus/Standard)or VGETINTERNAL ( Abaqus/Explicit),can be used to retrieve the internal node or element number corresponding to agiven part instance name and local number. Any number of solution-dependent state variables can be used in thefollowing user subroutines:.The state variables can be defined as a function of any other variablesappearing in these subroutines and can be updated accordingly.Solution-dependent state variables should not be confused with field variables,which may also be needed in the constitutive routines and can vary with time;field variables are discussed in detail in.Solution-dependent state variables used in, andare defined as state variables at slave nodes and areupdated with other contact variables. Alphanumeric data, such as labels (names) of surfaces or materials, arealways passed into user subroutines in the upper case. As a result, directcomparison of these labels with corresponding lower-case characters will fail.Upper case must be used for all such comparisons. An example of such acomparison can be found in.It illustrates the code setup inside user subroutinewhen more than one user-defined material model needs to bedefined. The variable CMNAME is compared againstMAT1 and MAT2(even in situations where the material names may have been defined asmat1 and mat2,respectively.). Abaqus/Explicitis installed with both single precision and double precision executables.
Touse the double precision executable, you must specify double precision when yourun the analysis (see).All variables in the user subroutines that start with the letters a to h and oto z will automatically be defined in the precision of the executable that yourun. The precision of the executable is defined in thevabaparam.inc file, and it is not necessaryto define the precision of the variables explicitly.
Most user subroutines that are used to define material, element, orinterface behavior are called twice per material point, element, or slavesurface node in the first iteration of every increment such that the model'sinitial stiffness matrix can be formulated appropriately for the step procedurechosen. The subroutines are called only once per material point, element, orslave surface node in each succeeding iteration within the increment.By default, in transient implicit dynamic analyses Abaqus/Standardcalculates accelerations at the beginning of each dynamic step.Abaqus/Standardmust call user subroutines that are used to define material, element, orinterface behavior two extra times for each material point, element, or slavesurface node prior to the zero increment. The extra calls to the usersubroutines are not made if the initial acceleration calculations aresuppressed. If the half-increment residual tolerances are being checked in atransient implicit dynamic step,Abaqus/Standardmust call these user subroutines (except) one extra time for each material point, element, or slavesurface node at the end of each increment. If the calculation of thehalf-increment residual is suppressed, the extra call to the user subroutinesis not made.User subroutines, and, when used in plane stress analyses, are called moreoften.
If there is any doubt as to how often a user subroutine is called, thisinformation can be obtained upon testing the subroutine on a small example, assuggested earlier. The current step and increment numbers are commonly passedinto these subroutines, and they can be printed out as debug output (alsodiscussed earlier). The iteration number for which the subroutine is called maynot be passed into the user subroutine; however, if printed output is sent fromthe subroutine to the message (.msg) file ,the location of the output within this file will give the iteration number,provided that the output to the message file is written at every increment.
Configure ABAQUS to run user subroutinesHere are instructions on how to configure ABAQUS to run user subroutines.They apply to installation within University of Cambridge Engineering Department only.Please note that the following software is required to run ABAQUS with user subroutines:. Microsoft Visual Studio 2005 Professional Edition.
Version for 2008 will not work. Intel Fortran Compiler Version 9.1.
Later versions will not work. Click on the Start Menu and open the Run dialog box. In the dialog box, type the following:diva-appservwindowsabaqus. Open folder 6.8, then Documentation, and double-click on setup.exe to install ABAQUS documentation. Follow the on-screen instructions from the ABAQUS installer. Once ABAQUS documentation is installed, go up one folder and open folder Product. Double-click on setup.exe to install ABAQUS product.
Follow the on-screen instructions from the ABAQUS installer. Enter for the licence server:27000@abaqus-lmserv. Borrow the Visual Studio CDs from the Design Project Office. Insert Disk 1 of Visual Studio, right-click on the D:/ drive and select Autoplay. Follow on-screen instructions and insert Disk 2 when prompted. There is no need to install the MSDN library.
Install the licence for Intel Fortran Compiler. Run the executable to set-up Intel Fortran Compiler 9.1, and follow on-screen instructions. Find the path for the file ifortvars.bat, which will be similar toC:Program Files (x86)IntelCompilerFortran9.1em64tbinifortvars.bat. Click on the Start Menu, click on Programs, find ABAQUS and right-click on the ABAQUS Command window. Click on Properties.
In the Target dialog after the/ksymbol, add a blankspace, then the path toifortvars.batbetween double quotation marks.