Science topic

# Abaqus - Science topic

Explore the latest questions and answers in Abaqus, and find Abaqus experts.

Questions related to Abaqus

Is it possible to get the coordinates of all integration points in an element in ABAQUS UMAT?

I know that it is possible to get the COORDS of one integration point, but my UMAT (based upon mechanism based strain gradient crystal plasticity) requires that I must have the COORDS of other integration points as well in the same element.

I wish to model the crack on composite beam using ABAQUS software. Can anyone tell me the procedure?

ABAQUS CAE (finite element program) treats each inclusion and a matrix as an independent part and therefore the mesh of one part (inclusion) is not connected with the mesh of another part. That is why the user needs to enforce displacement continuity conditions on all interfaces between inclusions and the matrix in order to "bind" them into a single model. This process is very inconvenient and time-consuming especially if there are many inclusions. How can I avoid this and make the mesh of one part dependent on the mesh of another part automatically?

I am trying to model a Micropipette Aspiration experiment, which is in fact creeping of a portion of a hyperelastic thin wall spherical membrane into a rigid pipette as a result of applying negative pressure (suction) through the pipette.

I obtained the equibiaxial data from my experiments and accordingly defined the test data in the Material properties section in ABAQUS. The problem is although in reality (experiment), there is up to 50 % nominal areal strain (in the portion of sphere which is sucked into the pipette), my FE model in abaqus/standard (quasi-static solution) would be aborted after experiencing 7% areal strain with unknown errors and warnings such as

I have used almost all possible hyperelastic models in my FE analysis (to find which is the best fit) but they didn’t work out and they all got aborted in the same point of running. Also, I have tried different contact conditions and considering different steps of solution but they didn’t work for me so far.

Does anybody think that I should write any subroutine (UMAT,…) to sort this problem out? If yes, which one? Given that I am new in using ABAQUS, I would be grateful if anybody could kindly send me any file/tutorial in this regard or point me to the correct direction.

For your further consideration, I have also attached a figure of the experiment I am trying to simulate.

Any guide or suggestion would be much appreciated.

Many thanks in advance.

Navid

My material property like density, conductivity will change with porosity as well as with temperature. I have the data for change of porosity with time. The change of porosity is linear with time.

I have no idea how I can change the properties with time.

Can you give me some idea please?

I am a new user of Abaqus. I want to ask whether it's possible or not to perform fatigue life analysis using standard abaqus (without sub-routine). If possible, then how to define their loadings and where can I get their results. I hope that somebody can share their experiences here. Many thanks.

Can anyone help me with a video tutorial, or a step by step guide, or a CAE/INP file of bullet impacting a material. I would like to use this approach, to model penetration of soft tissue using a bed of needles in Abaqus. Currently in Abaqus I have used the surface to surface contact, approach as a starter, and would like to progress to actual penetration.

Erroneous Spatial displacement for coupled Temp-Disp Problem in ABAQUS?

There are 3 parts in a assembly, Lower mould, Upper mould, a rectangular block placed at center of the blocks. The block is sitting over the lower mould. Upper mould is in just contact with the block.
Objective is to find residual stress analysis in the block. There is no external forces. Only thermal loads are acting on the entire system. It is being heated and then cooled rapidly.
In coupled temperature displacement, after the analysis I find a spatial displacement of the block in the Z- direction. Uexpan user subroutine is being used for capturing the thermal expansion behaviour of the block. Kindly can anyone suggest solution for it?
I have tried *TIE option: result -> the block pulls the lower mould.
I have tried Coupling DOF constraint : Result-> simulation runs like a infinite loop. No step increment is taking place.

Actually my research area is fault diagnosis of beams. So I want test the modal analysis of cracked composite beam. So, how can I create crack over composite beams?

I have to model fiber-matrix debonding in polymeric composites using cohesive elements. Can anybody help me?

When I was doing numerical simulation by using Abaqus software for a deep drawing process, I got the output result for stress in that tha contour plot colour indication is in grey. What is the indication of that colour? Does it mean failure condition?

For every load step, fortran code is complied from beginning, when we link with abaqus. My question is: if, for example, I am solving for a(t) and 't' is time at current load step and I want a(t) value in the next load increment a(t+1), how will I get value of a(t) ? Because for every load increment fortran code run from beginning and I don't know how to call/use, all previously solved/stored value. Can any one help?.

In numerical integration of (B^t*D*B) for calculation stiffness matrix, can its value (B^t*D*B) be printed at integration points. Also, is it possible to print value of weight at each integration point which is being taken by abaqus.

I am trying to model a composite cantilever beam using a solid section on ABAQUS. This requires defining elastic material property using engineering constants. Can anyone help me define transverse properties of the material in ABAQUS/CAE?

Thank you.

Could anybody help me with the analysis of a 2D 3 story single bay frame on Abaqus? I have obtained my pseudo acceleration of a given earthquake and I am trying to apply it on my model so that I can conduct a response spectrum analysis. I am having two problems: after I upload my data on my acceleration spectrum table (acceleration, frequency and damping) and I try to run the analysis I get an error message saying that my frequency needs to be continuously increasing. Given that these are pseudo acceleration graph data I am using, my frequency can not always be increasing..It's a highly non linear graph..I tried overcoming that problem by keeping the values that only indicated the frequency is increasing. When I did that I got no error messages however this is where my second problem appeared. When I go to history output to plot my displacements/ acceleration etc.. the results are blank. As if nothing is applied on the frame. Does this have something to do with my boundary conditions? or with the fact that I manipulated the acceleration spectrum maybe?

This work is for the submission of my masters thesis. Your help would be much appreciated.

For a start, I just want to make a 2D-axisymmetric model.

How to define/apply fatigue load(sin varing fuction) in Abaqus?

I could not find any damage model associated with Mohr coulomb plasticity model. When I try other damage models there was an error that those could be used with other plasticity models except Mohr Coulomb plasticity.

Does anyone know how to refer damage associated with Mohr Coulomb model?

I have used the Abaqus software for deep drawing process.In that I was not able to get the output for shell thickness (STH) .Can anyone help me to get the output.

Could anyone explain or post a video tutorial in modeling of MMC rod in ABAQUS?

I used the section force command but wondering if there is a visual way to do it.

I wrote an VUEL. However, there are some problems on it. When you stretch it the element volume increases. You can get the poisson ratio and it's positive 0.33. I want to check the inner calculation process by abaqus itself. Did anyone do this before? Abstract these matrix from abaqus?

I am printing the stiffness matrix from abaqus for C3D8 element and also I have written a code for 8 noded brick element with full gauss integration. But stiffness matrix is not matching. Does C3D8 takes care of shear locking or something else?

For a cantilever TWB, U cross section, 10 Hz excitation, I tried using general contact in Abaqus/Explicit (edge to edge contact, normal interaction: hard contact; tangential: rough), modeling with shell elements for 3 seconds of simulation time. It works, but here is the point: Is it a realistic simulation? The crack, located at a flange, is regarded as a very sharp V-notch: with mouth of 0.001 mm (length of the beam: 2000 mm; flange: 100 mm; crack depth: 50 mm).

I would like some opinions. Thank you in advance.

I’m trying to install a free Windows Fortran compiler to run Abaqus subroutines. I found a couple of compiler, gcc and open64, but they seem not windows compatible (I couldn't install them). If you have any alternative Fortran compiler, please let me know. In addition, would be helpful an explanation about how to link the compiler to Abaqus (I mean what to write in the environmental variables and so on).

We have used gasket elements with Abaqus/Standard for a long time. But it is even not possible in Abaqus/Explicit. Does anyone have any idea how can we solve this problem?

Why is there alternate layers in visualization when I select section points - top in composite layup?

Alternate quarter by quarter.

At present I am facing a memory problem in ANSYS (APDL) while meshing as well as solving the solution for the model. I know that in Abaqus there are no memory problems while meshing and solving solutions for applied load.

So if I change my analysis from FEA to Abaqus, will it affect my results because I need to validate it? The analysis in FEA will be Tensile and Flexural and the same has to be simulated in Abaqus.

I am using unstructured mesh for analysis. The number of points where I need displacement is high. So, rather than selecting or giving every coordinate individually, I would prefer to input all coordinates at once if possible.

Could someone give me some advice how to get a reasonable ply contour plot for the solid element composite?

I'm trying to display the individual ply stresses in a composite OHT model.
I am modelling 3D composite damage, therefore I used a composite layup with solid elements.
The envelope plot seems fine, but if I display the individual plies, the orientation of the displayed
contour surface is not corresponding with the laminate surface.
http://abaqus-users.1086179.n5.nabble.com/Composite-Contour-Plot-td17508.html

Drilling behaviour of natural fiber composite.

I am trying to penetrate a hyperelastic material with a single needle model and have discovered that I can achieve this using abaqus explicit, but will need to use element deletion.

Is there a rational way to select the penalty contact stiffness values based on the elastic properties of the contacting materials? It would seem reasonable to relate the pressure - overclosure function to the bulk modulus, but how?

Air cavity simulation in ABAQUS

I am going to model the polymer matrix composite tube and find out the cutting forces while machining.Can anyone recommend which software show better results?MSC/NASTRAN or ABAQUS?

We have a problem finding a suitable damage model for poylmer concrete. The most important characteristics of this concrete is that there are nonlinear elastic-plastic behavior with large volume change at the plateau zone at nearly constant pressure, pronounced hardening under clamping conditions after the plateau zone and very early damage under shear loading conditions without clamping.

I've given the time history in Load-> tools-> Amplitude -> Amp 1. I've given a

small time history for practice. For the gravity step, the model deforms, but for the apply acceleration step, the model doesn't deform even if I give large values.

Plasticity behavior of lamina.

How can I combine different materials from ABAQUS library and UEL at the same time?

I want to run a composite material simulation from Abaqus library, linear elastic for a material and a UEL subroutine for the other material?

I need guidance how to calculate J-integral in Abaqus.

Can anyone recommend software or numerical methodology for modeling pile in liquefied soil?

I'm working on my thesis that needs numerical modeling and now I am looking for good software for modeling liquefaction in soil, with the capability to consider pile as a structure element in the soil.
Abaqus might be a good option but I don't know its performance in modeling soil, especially the liquefaction phenomenon.

Is it possible to model plastic behavior of fiber reinforced polymer composite in Abaqus (without using subroutines)? As u know, just elastic behavior for lamina can be defined in property module.

How do I carry out analysis of RC beam for reversed cyclic load using Abaqus?

The problem has been solved :)

For who's interested in this topic, we have published a paper in E.S journal with detailed information about the damage evolution in DPM among new approach for obtaining dt,dc. This is a link where you can download the Journal version http://www.sciencedirect.com/science/article/pii/S0141029616312317

All I know is that the journal file should be saved as a python file and then the saved filed can be invoked from Abaqus CAE.

I am trying to simulate foam using crushable foam in Abaqus under the uniaxial compression. As I understand, I need to insert true stress and plastic strain (from uniaxial compression test) for foam hardening. However, the foam that i am using has poison ratio 0. Can I assume the engineering stress equals to the true stress as there is no change in the Area. I have tried inserting true stress and plastic strain but it gave me a less stiffer compressive stress strain curve as compared to the experimental data. I attached the uniaxial compression test data here. I would really appreciate your advice.

The problem is that I want to define initial strain field for my model and leave the other fields such as displacement Zero. I used the predefined field option in ABAQUS and chose the initial state but the problem is that I want the displacements to be zero.

I am making a coupled temperature-electrical-structural model for spark plasma sintering. I have used Abaqus standard.

The model worked for simple geometry involving only 3 parts (2 punch and die), but it is not converging for my original model which has 2 punch, sample, die, 4 spacers.

The error that I am getting is -

Too many attempts made for this increment

There are few warning messages aswell

1. Displacement increment for contact is too big

2. SURFACE INTERACTION "interaction name", ASSOCIATED WITH ONE OR MORE CONTACT PAIRS WITH SURFACES HAVING UNDERLYING ELEMENTS WITH ELECTRICAL, TEMPERATURE, AND DISPLACEMENT DEGREES OF FREEDOM, DOES NOT HAVE ANY ELECTRICAL INTERACTION DEFINED. NO ELECTRICAL INTERACTION WILL OCCUR.

I used to SI units and applied a pressure of 5 MPa at the top of upper spacer.

Can anyone help me?

I have attached the input file here

Hello to all.

I don't know if anybody here uses Abaqus, but I'll post a question here.

I've tried to compute simple geotechnical problem in it by using Mohr - Coulomb criterion as a constitutive model, and I came up to a problem.

When I assign properties to continuum as a "Homogeneous", Abaqus gives me a message that I cannot use MC in plane stress conditions. Ok, I understand that, but when I change to plane strain conditions, Abaqus starts to give me a messages that I haven't assigned nodes to section.

Does anybody know, or at least has an idea how to solve that?

I am modelling an extended end plate steel connection with ABAQUS. Here is my question; what should be the interaction type with end plate and and column? Surface to surface or node to surface? Also what should be the sliding formula, small sliding or finite sliding?

I performed a simple 3d analysis of a beam (5x5x50) with steel properties (E=206e3 and v=0.33). As I decreased the element size, the results drastically changed. The changes are recorded in the excel sheet.

Why is the stress increasing exponentially?

Which region should we label 'safe or acceptable'?

I am using axisymmetric modeling to simulate indentation and the indentor is an analytic rigid body while the workpiece is a 2D deformable body. I am using ABAQUS 6.12 version and did displacement controlled test. Both indentor and work piece are modeled as axi symmetric. When I do the indentation, I get an unwanted reaction force along the perpendicular direction to the loading axis (RF1) which is high compared with the reaction force along the loading axis. I imposed encastre boundary condition for the bottom of the work piece and Y axis symmetric boundry condition for the workpiece axis as well as to the indentor. Could you please help me whether there are other things to be satisfied to get rid of that RF1 component?

CPD model in abaqus does not consider pinching effect.

Does anyone have experience with porous structures modelling in Abaqus?

I´d like to simulate stress-strain behaviour of titanium porous structures prepared by powder metallurgy.

I am modelling BMG using abaqus and i have a problem of introducing shear band formation to the model.

Analyzing wave propagation in plate by using the dynamic analysis.

What is the element that I should use it to find fracture intensity factor?

I also need to define the zig-zagged path of the heat source, which must have constant temperature.

Can anybody tell me how i can open .inp files in Abaqus/CAE? I tried to open dcb_vcct_fatigue_3d.inp (Abaqus Example Problems Manual 1.4.7.) I found something about "abaqus fetch command". However i always get an error message (SyntaxError: invalid syntax), after i write "abaqus fetch job=dcb_vcct_fatigue_3d.inp" to the command line.

Does anybody know how to use fetch command or how can i open this example input files?

I am doing transient thermal analysis of rapid prototyping and I am having a problem with script writing, which is used for the continuous element activation process. I want the process to be continued for several stages. Can anyone with expertise in this field some advice?

When working with hyperelasatic materials in any FEA software, we need to select FE models such as Ogden, Van der Waals, Yeoh, Mooney-Rivlin, etc. And I also assume that you know that hyperelastic materials can handle 600-700% strains when stretched. FE Models are required to match the experimental results with minimum errors. In my case, the Yeoh 3rd degree model fits reasonably well.

I am trying to identify that the YEOH (3rd Degree) FE model falls in to which category of strain percentage. What I mean is that the 3rd Degree Yeoh Model is acceptable in which strain ranges?

I would like to ask the users of FEM/ FEA about the topics that they believe are missing and if not missing, topics that are not discussed in great detail. Also the topics on which FEM/ FEA users would like to see books or research on?

Are the users of FEA packages happy to get help from 'Help' integrated in the software or would like a summarized version of that help so they can find what they need instead of clicking links upon links just to find out a simple definition?

In Abaqus, you have the option to import your assemblies made in Creo (formerly Pro/E) as one single part or as an assembly. The difference is that, when imported as a single part, no interactions are required because Abaqus treats it as a single part no matter how complex the geometry is.

But when imported as an assembly, individual parts are imported which can be assembled later on. But with this kind of import, interactions are required. However my contacts (interactions) would be defined as 'TIE" which means it is a fixed part.

My question is that for a same assembly, should my results differ from each other in different import methods? If so, then which is an ideal way to do your analysis considering importing in part mode, it is very easy to run the analysis with minimum errors?

In Abaqus when we want to define a concentrated force (CF) at a certain point but it is coupled with other surfaces/ nodes so the force is transfered to those surfaces or nodes.

Once you made a reference point (RP) and then under interactions module, you define kinematic coupling. In coupling option, when the surface is selected, the analysis solves without any problems. When edges are selected, again it solves. But when the nodes are selected, the error pops up 'too many attempts made for this increment'. Why?

Any ideas or suggestions?

In Abaqus there is something called 'Global CSys' and then the user is allowed to make several others according to the model and requirements to define forces and other things. However, whenever you solve an analysis, the default result shown in Visualization Module is according to the Global CSys even though your BCs and Materials and other things defined using the new or custom csys. We need to change the csys from Results > Options.

Is this correct? Or there is no need to change the CSys from results > options. The results vary very slightly but it's a bit confusing.

Any advise or comment?

I'm modelling the interaction between plough tool and soil.

Abaqus, Ansys and Patran/ Nastran

I have used a lot of software during my degree and professional work and I know it depends on what you are trying to solve determines the advantages of a particular software. Hence, this question is not about which software is better.

I am trying to solve a very simple composite problem. I have a circular plate subjected to 70 bar of pressure. The plate is made of E-Glass and Epoxy through hand layup process. 50 plies of 0.5mm are used to make up the thickness of about 25mm. The plate is bolted (25 bolts equally divided).

Model: shell

Boundary Conditions: Pressure applied on the face, bolts = encastre.

Mesh: Tet/ sweep fine mesh

Why am I getting different results in Ansys Multiphysics 14.0, Abaqus 6.12 and Patran/ Nastran 2012? Am I doing something wrong?

For example: Max. Disp. in Abaqus 6.12 = 1200mm where as Max. Disp. in Patran/ Nastran 2012 = 3400mm

I wasn't aware about distributed and parallel computing and advantages they had, but now I have been informed. Hence, I would like to build a new cluster to perform heavy mathematical calculations in Matlab and Abaqus. I have never clustered before and that's why I need assistance to setup.

Current workstation I own:

Dell Precision T5400

2 x Intel Xeon 2.5 GHz

16 GB RAM (2GB x 8)

1 x Western Digital 1TB HDD 7200 rpm

1 x nVidia Quadro FX4600 768MB GPU

1 x 870W PSU

OS: Windows 7 Ultimate 64-bit

2nd WS: I can buy another WS similar configuration to the one I own

I am not bothered about OS, I am willing to cluster with either Windows or Linux. However, my software are compatible with windows 64-bit only.

I try to model couple thermal electric phenomena using two electrodes placed on the skin. All the settings of the Abaqus program seem to be fine. I check the job, which works well and I submit that. After submission I got the comment: Too many attempts made for this increment. I did some corrections and manipulations with the value of increment size in STEP; however, I cannot possibly get the optimum.

My questions are: Do you know what should be the settings in my case? Maybe I missed some parameters earlier, before getting to STEP.

Working with axis symmetric model in Abaqus. I have a sandwiched structure which consists of rubber and metal plates stacked on each other. In 2D I have a single edge which is shared both by the metallic section and the elastomeric section. Defining the material properties is a nightmare.

How will I define the cross section of sandwich structure in 2D Axis-symmetric analysis?

I have programmed a UEL subroutine for a 3D cohesive element and I have a problem.

When I do the testing using a 3D single element, the subroutine converges if and only if I put initial boundary conditions on all nodes.

For example, imagine the bottom surface is fixed and the upper surface is prescribed a displacement to perform a tensile test. Then, it is necessary to impose the lateral displacements in order to obtain convergence. If this latter constraint is not applied, the subroutine does not work (wrong displacement values obtained, error message). It seems that stiffness matrix becomes ill conditioned in the absence of sufficient boundary conditions. Yet, I observe that the cohesive elements already available in Abaqus cause no problem. For these elements, the convergence is always obtained even if the lateral displacements are not applied.

Why does this work well with Abaqus elements, but not with a user element in UEL? I verified my subroutine and I think that I have strictly implemented the classical formulation for cohesive element.

I am trying to match Abaqus FE results with experimental results. I have a quad lap specimen, rubber block measures 25.4 x 25.4 x 6 mm. For this test, assume there is only 1 rubber block rather than 4. From experimental results, 300% of shear strain equals 3 which means at original thickness, shear strain equals 1.

Keeping that in mind, I modeled 2D plane stress, 2D plane strain and 3D specimens and run the analysis with plane stress, plane strain and 3D stress elements respectively. The shear strain I am getting is 1.5 at 300% shear strain. I have also noticed that when using 100% of shear strain, I get around 0.88 shear strain, which means the deviation is 12%, however as I increase to larger strains, the deviation increases dramatically.

Rubber model being used: YEOH 3rd Order

Test data used: Uniaxial and Volumetric Compression

Can anyone help me in modeling shear strain of rubber like materials?

I have developed a phase field model in Comsol and I want to import the result to ABAQUS, and perform stress analysis using UMAT.

Helpful tips from my colleaques that use ABAQUS is needed.

Is there any way to model a viscoelastic material in Abaqus using the results from tensile and relaxation tests of dog-bone shaped samples of adhesives?

I am modeling a truss structure, in which elements have different temperatures. I don't want to use thermal analysis, because there are no heat flows or thermal changes. The analysis is static and the effect of temperature is just initial strain.

I'm trying to carry out a seismic analysis for 2D frame, I tried to define a new step with new boundary conditions "release the U1", which is the direction of the input "X" direction, and deactivate the initial boundary conditions in this new step, but the drift is not logical.

Can anyone help me - what is the best way to improve my simulation?

I am a new Abaqus user. I tried to make a simple model of asperity flattening by imposing a downward displacement into an analytically rigid die compressing an Aluminum 3 asperity. I used Abaqus standard, pairwise contact with Hard normal behavior and friction less tangential behavior, and 2d symmetrical model.

I expect to have the maximum PEEQ and Mises stress on top layer ( based on hertz contact theory) but it is observed in under layer elements. Actually maximum PEEQ starts from contact area but gradually it goes down to the underlays. Also maximum Mises stress is a little bit lower than contact surface.

I tried surface- to-surface and node to surface discretization method, different contact constraint enforcement methods (Direct, Penalty, Augmented Lagrange), different elements (CPE4R, CPE3) also higher order elements with reduced integration points. but I still have the same problem. I have attached some pictures of initial model, Smises and PEEQ contours. Do you have any idea what's wrong?

Some papers focus on the FEA of 2D cellular structures (in Abaqus). It seems that the yield surface can be obtained by applying biaxial loading to a specific 2D cellular structure (honeycomb). But how should the yield surface be plotted?

I am trying to implement the Yoshida-Uemori kinematic hardening model in Abaqus. Unfortunately, I cannot figure out how to handle the the non-isotropic hardening surface in the stress-integration. Does anybody know where I could find an algorithm for the integration of this model?

Ghaei and Green have written articles on the explicit and implicit integration of this model, but the papers are not very clear about the non-IH surface.

In FEM, when shell elements are used, the stresses we obtain do not include peak stresses. But while calculating fatigue damage, we need to include peak stress too. How do we account for it?

Could anybody compare shell element and solid element, with as many points as possible. Shell elements need low computational time. Is it that if we have high speed computer, it is better to go with solid elements? What are the other advantages of shell element?

Working with hyper-elastic materials in Abaqus/ CAE, I would like to convert the following:

Logarithmic (true) strain tensor (shear strain components of tensor)

TO

Engineering (nominal) strain tensor (shear strain components of tensor)

Does anybody have any freeware program, matlab code, formulas or a method that can be shared so I can achieve the task above?

The purpose of doing this work is to transfer the results of structural analysis of ABAQUS software to MATLAB software.

I want to create an UMAT for the analysis of damage and failure in FRC

I have an .stl file that I want to analyse with Abaqus software. I know that I can import a stl file to Abaqus but I want to change its mesh size and kind. I then need to import it as a solid file.

I would like to receive some advice about creating a partition and then meshing a part in the proper way. I made a hexagonal 3D elastic solid with curved corners. I tried to use partition cell extrude cell/sweep edge in the the curved edge, but the solid it has not been partitioned yet. I attached the part image.

I've been trying to get a multi-surface plasticity model running, without finally succeeding.

I am coding the algorithm Simo & Hughes give in "Computational Inelasticity" in Box 5.2a-c into an Abaqus-umat written in fortran. I apply it for perfect plasticity (at the moment), therefore it is simplified from the original.

Unfortunately, my code does not provide proper results even in a quite simple example (two surfaces only) that can be more or less followed.

Nevertheless, the algorithm does work if only one surface is active. These results are verified by a single-surface model. I assume therefore, that the algorithm is OK in principle, only the combinatorial terms are somehow not working properly. I have also rewritten the code in mathematica which yields the very same results - wrong ones in case of multiple active surfaces.

Questions to the community are:

- Is the algorithm given in Simo & Hughes working at all?

- Has someone experienced some troubles with this as well? Were there any minor/major/obvious/hidden misinterpretations or errors in understanding the procedure? Any hints what one can make wrong?

- Does anyone know of a similarly well-documented algorithm for multi-surface plasticity?

- Any other information that may be helpful?

I need to determine the element characteristic length L in Abaqus to identify the plastic displacement for ductile damage evolution. I know that characteristic length is roughly element diagonal dimensions but the problem is that my elements are around a typical cylindrical dog bone specimen. Is there any way to get the length using a specific tool or do I just need to approximate it with element dimensions?

I am modeling a multi-layer bar. I have experimentally obtained storage/loss moduli data for individual layers,which I am giving as input in Abaqus. I want to get the viscoelastic behaviour of the whole bar as output.

I am trying to run the FEM simulations of an Si anode material used in a lithium ion battery. I am able to impose the equivalent thermal stress on the material. However, I wonder how to specify the charging rate (fast/slow insertion of lithium ions into Si) of the anode in the lithium ion battery while doing FEM simulations using ABAQUS?

There is a vertical bar of height H, and we have varying temperature profile along the height, The curve is quite zig-zag. I have divided the curve into many parts and got the equation fitting each part. Then I have used the analytical field option to give the equation for each part. But as each equation is approximated, there is discontinuity at the point joining the two parts. (The temperature at that point should be the same, but as there are 2 different equations at that point, dr is discontinuity). Could anyone suggest how to solve this problem (other than writing a program)?

Can anyone help me to make the user subroutine UMATHT used in ABAQUS simulation for lithiation process in lithium ion battery (LIB)? I am working on anode part of LIB and need to run an FEM simulation. However, I am not aware of the programming part of this subroutine. I would really appreciate comments from people who know about it.

I have DMA data and I need a prony series coefficent in order to do viscoelastin modelling in ABAQUS.

How can I make torsion on a tube in Abaqus?

Torsion Load - Abaqus