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PolyUMod Integration with MSC Marc and

Mentat

Introduction

This document demonstrates how to run PolyUMod

material models with MSC Marc and Mentat

The example shown here is for MSC Marc version 2017,

but the procedure should also work for other versions of

Marc

This document assumes that you already have installed

PolyUMod and MCalibration

For technical support use our online Help Center

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Step 1: Start MCalibration

Start MCalibration and

click on the

Calibrate button

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Step 2: Create Material Model

The next step is to

select a material

model

Click the Set Material Modelbutton

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Step 3: Create Material Model

For this example

select the PolyUMod-Bergstrom-Boyce in

the list of material

models

Click OK

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Step 4: Create Material Model

Actual experimental

data should also be

read in and the

selected material

model should be

calibrated to the

experimental data.

Here we will just

accept the default

material parameters.

Back in the main

window click the

Export Model button

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Step 5: Create Material Model

Select MSC.Marc as

the format and click Save

Then specify a file

name and click save

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Step 6: Create Material Model

The txt-file created by MCalibration contains commands that need to be added to the MSC.Marc dat-file

The file contains one command for the parameter section of the dat-file

The material model should be added to the model definition section of the dat-file

The PolyUMod material model is defined as a md_hypela2 subroutine

The material model commands can be manually added to a dat-file or be added using Mentat

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$$ Calibrated with MCalibration$$ Units: [length]=millimeter, [force]=Newton, [time]=seconds, [temperature]=Kelvin$$ Material Model: POLYUMOD-Bergstrom-Boyce$$ Calibration file name: polyumod_with_marc.mcal$$------------------$ Parameter Section$------------------$--- define the number of state variables ---state vars, 14, 0$$-------------------------$ Model Definition Section$-------------------------MATUDS$ (subName, matid, notUsed, nrInt, nrReal, nrChar)hypela2, 1, 0, 0, 25, 0$ MM, ODE, JAC, ERRM, TWOD_S, VERB, VTIME, VELEM,4, 0, 0, 0, 0, 1, 0, 0, $ VINT, ORIENT, NPROP, NHIST, GMU, GKAPPA, FAILT, FAILV,0, 0, 25, 13, 1, 500, 0, 0, $ (params)2, 3.5, 500, 3, 0.05, -0.5, 0.5, 8, 0.01, $hypoelastic$ L2: (nr of data sets)1,$ L3: (matid, anisotropic, rotflag, notused, notused, matname)$ (--need to update the matid--)1, 0, 1, 0, 1,mat$ L4: (density, thermExp, conductivity, specHeat, resistivity, heatTransDens, emmisivity)1e-09, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0$ L5: (table ids)0, 0, 0, 0, 0, 0, 0$ L6: (list of elements -- Need to update)1,$---end material model---

Step 7: Setup FE Model in Mentat

The next step is to

setup a FE model

using Marc Mentat

This demonstration is

using version 2017.0.0

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Step 8: Create 2D Element

Create a 2D element using the Geometry & Mesh tools

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Step 9: Convert to 3D Element

Expand the element to

3D using Expand tool

in the Operationssection

Remove unused

nodes: Geometry &

Mesh > Operations >

Sweep > All

Click OK

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Step 10: Assign Solid

Assign a 3D solid

using: Geometric

Properties > New

(Structural) > Solid

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Step 11: Assign Material Model

Assign a material

model: Material Properties > New > Finite Stiffness Region > Standard

Select Hypoelastic,

and method User Sub,

Hypela2

Make sure

“Deformation Gradient

& Rotation Tensor” are

passed to the user

subroutine

Then add the one

element

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Step 12: Fixed Boundary Conditions

Prevent the x-

displacement of the left

side

Prevent the y-

displacement of the

bottom side

Prevent the z-

displacement of the

back side

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Step 13: Displacement Boundary Conditions

Pull the right side a

distance of 0.1 in the

x-direction

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Step 14: Assign a Temperature

Set the initial

temperature: Initial Conditions > New (State Variable) > Nodal Temperature

This step is only

needed if the material

model is temperature

dependent

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Step 15: Define Load Case

Define a new load

case using: Load Cases > New > Static

Select Multi-Criteria for the time

stepping approach

Select the load case

time

Click OK to save the

load case

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Step 16: Define Job

Define a new job

using: Jobs > New > Structural

Select the defined load

case to add it to the

job

Click on Analysis Options

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Step 17: Set Large Strains

Select Large Strain

Click OK

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Step 18: Select Job Results

Click the Job Results

button in the Job

Properties dialog

Select suitable output

results

Click OK

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Step 19: Specify State Variables

To specify the number of

state variables that the

PolyUMod material

model needs click on the

Job Parametersbutton, and enter the

value in the dialog

The required number of

state variables is listed

in the file that is

exported by

MCalibration

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Step 20: Specify Material Parameters

To specify the material parameters

that the PolyUMod material model

needs click on the Input File Text button

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Step 21: Specify Material Parameters

Click on the Model Definition button, then

click the Read Model Text File button

Select the dat-file that was

created by MCalibration

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Step 22: Specify Material Parameters

Remove all lines that are not

part of the MATUDS

command

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Step 23: Specify Material Parameters

In this example the

MATUDS commands

consists of 10 lines

Click the OK button

Then back in the Job

Properties dialog click the

OK button

Note that Mentat currently

does not have the ability to

run a custom executable

Select: File menu > Export > Marc Input…

Save the file at job.dat

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Step 24: Verify DAT file

The exported dat-file

contains the lines that were

added for the PolyUMod

material model

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Step 25: Setup BAT file

The created dat-file can be run from a command window

A more convenient way to launch the simulation is to write a short bat-file

Before running this bat-file you need to copy the Marc_PolyUMod.exe and rlm1222.dllfiles to the current working directory

These two files are located here: C:\Program Files\PolyUMod\PolyUMod_Marc2017

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Step 26: Run FE Simulation

Run the simulation by

double-clicking on the

created bat-file

The simulation should then

run to completion

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Step 27: Analyze FE Results

The FE results can

be analyzed using

Mentat by double-

clicking on the

job.t16 file

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Conclusions

All PolyUMod material models can be calibrated using

MCalibration

The calibrated material models can be exported to Marc

dat-file format

Mentat can read in the material model and setup the FE

simulation

The FE simulation is then run using the Marc solver

More details about the PolyUMod library is available in

the PolyUMod User’s Manual

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