Science topics: FE Analysis

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# FE Analysis - Science topic

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Questions related to FE Analysis

Dear members,

I am trying to predict temperature distribution in laser melting process using FEM. It is a 3D transient heat conduction problem.

I have modelled it without considering phase change at the melting temperature of metal, but I am not able to understand how to incorporate the phase change, particularly how to handle the nonlinearities associated with the phase change (the latent heat, enthalpy as well as heat conductivity might not be continuous at the point of phase transition)?

Please provide some resources or any kind of help will be helpful.

Sincerely,

Ravi Varma

Hello everyone,

I've written a rather simple linear elastic UMAT for orthotropic materials. I found that my output stresses are different from stresses should be.

For example:

In my model, I set a max load of 25 MPa and min load of 2.5 MPa (aka cyclic load ratio R=0.1). In my UMAT a wrote a line "write(*,*) "stress(2)=", stress(2) " to see how applied load matches outputs. I expect see alternation of 25 and 2.5 (when increment time=0.5), but I see the following:

stress(2)=0 - okay, initial step

...

stress(2)=-25 - okay

...

stress(2)=-49.99 ????

...

stress(2)=-2.5 - okay

...

stress(2)=-19.99 ????

then everything repeats

But in ABAQUS visualization stresses are as I set, 25 2.5 ...

Have you seen something similar? I'm bit confused, don't understand how it works.

If you have any ideas what can be wrong, let me know.

I have attached the UMAT subroutine file and inp file. Thank you.

Greetings to all.

I am new to UMAT in Abaqus and want to create

**UMAT**for**"shell"**elements for an isotropic and anisotropic material, can anyone suggest any reference material, book, or website link which can help me.Thank You

Hi,

I am modelling a beam reinforced with GFRP bars on ATENA 2D. The experimental and analytical load-deflection behaviours are in agreement with each other however, my FE model terminates 10 KN before the experimental load due to stress concentration near to loading plate. I tried to avoid it by increasing the plate's surface area but it didn't work. Please guide me on how to prevent stress concentration.

I am New to MDS simulation which software will be open source and free tutorial available for beginners?

Dear ABAQUS users,

I want to make a three-dimensional model of

**the three-point bending simulation**!What do you think is the best element to use in ABAQUS for this problem?

**C3D8R - C3D8 - C3D20R - C3D20 - C3D8I**Can you please tell me about

**the advantages and disadvantages**for each element or send me a reference for that!I couldn't find any example or useful info online. Can anyone familiar with altair help me with it?

Basicly, I want to study the optimized parameters of a I-beam under given BC and max stress/strain.

I have created the beam using HyperBeam standard I-section and assign PROD properties to the component. Now, I am stuck here. I want to link the desvar in size optimziation to the dimensions of I-beam parameters. How do I do this?

Thank in advance for any help!

Hello everybody
How can a

**three-dimensional FE analysis of a threaded screw**(inserted into a material with an insertion torque) be substituted with an**axisymmetric analysis**of the same problem?**Please kindly share good references' links if are available.**Best regards, Yunus.Dear Researchers:

I need help, please if someone knows how to, o can, help me, I'll really appreciate it

I am trying to solve a model of a Medium voltage Energy Cable. So I need to solve for the Temperature Distribution across the whole 2D cross section (my model is a 2-D Model).

I have two direct questions :

(first image) I am trying to use the coupled Joule Heating Multiphysics. This is the "Electromagnetic Heating (emh1)" section.

1. My first question is : Do I have to ad a domian of "Heat Source", or I don't need to add this Boundary Condition ?

And if so, on the "Heat Source" section is it correct to select "General Source" and then: "Volumetric loss density, electromagnetic (ec) for the "Qo" ? (as is shown in the first image attached).

2. And second. On the "Electric Current (ecs)" physics. Do I have to use the domain "Terminal" or the domain "External Current Density" ?? I have a fixed value dor the voltage in the problem, and I also know the electric resistance of my Cable

Does anyone know How to solve this ?

I am trying to analyse a large structure with multiple loading scenarios (independent - different loading directions), while considering geometric non-linearity. Using different steps is not sufficient, since each step starts off with the geometry shaped as it was at the end of the previous step.

I tried creating a dummy step just to deactivate all the loads from the previous step, but the non-linearity causes some distortion to remain even without any loads.

One obvious solution is to run each step in a separate analysis, but the model is quite large and the input file processing takes about about as much time as it takes the solver to solve a step, which would immediately double the time required to obtain the entire solution and there would also be redundant information in the result files (mesh data repeated in each result file). So creating a separate analysis for each step is something that I am trying to avoid for the moment.

Hello Researchers,

The FEM discretized (meshed) geometry/domain is considered stiffer than the actual geometry/domain due to the assumption of variation of the displacement within each element. This is analogous to the displacement being constrained to vary in a particular fashion within each of the elements. This results in the stiffness of the discretized domain being greater than the actual domain. As the element size decreases (or the number of elements increases), the constraint on the displacement loosens due to the smaller size of the element and hence, the smaller constraint zone. Thus, the stiffness of the meshed domain decreases and approaches that of the actual domain as the number of elements is increased.

**Based on the above reasoning, the natural frequencies (on increasing the number of elements) must converge from above to the actual value (i.e. converge from higher values to the actual value).**

- Can this be considered to be strictly true?
- Has any deviation from it been observed (i.e. convergence from below or lower values to the actual value) and if so how can that trend be physically explained/interpreted?

hello how to input materials parameter for the following

elastic - plastic material

I have the following parameters only

lame constants

yield stress

hardening parameter

young modulus and poisson's ratio

I know how to input everything except lame constants

I want to do FEM analysis on cold extrusion.

Dear all

Please find attached the image T.jpg.

The image of the FE model attached is a hollow body with some prismatic textures on the interior surfaces. Here I need to

**select all the nodes at the interior surfaces of the FE model**. I have tried to use:

*NSEL, S, LOC, X, X1, X2* but as the body is having a certain curvature on one side, all the required nodes are not getting selected. And as the number of nodes is many i.e. above 100000, graphical picking seems to be a cumbersome task.

Please help.

Hello everyone,

I found in some papers that the bolt joint can be conveniently modeled using the

*which has been integrated into many commercial FE packages.***thin layer element**In the tutorial

*, the authors have given a simple example (see Fig. 20 and Table 4 in section 3.5 of the attached PDF); however, it was completed in MSC. Nastran with which I am not familiar. I wonder if similar treatment can be done in COMSOL?***Modeling the dynamics of mechanical joints (S. Bogradet al, 2011, MSSP)**My final goal is to simulate how the pretension of the bolts affects the dampings of different vibration modes and I think the

*based method can be a possible solution. If anyone has ever done or seen similar simulations before? COMSOL based tutorial will be of great help.***thin layer element**Thank you so much for reading and I appreciate your help.

Best regards,

Hao

Greetings,

We know that locking in the finite element method (FEM) is a numerical artifact due to the choice of the approximation functions. A couple of implications of locking in a static analysis can be mentioned as follows

- A FEM model of a beam subjected to a point load at its tip can severely underpredict the tip displacement if the FEM model is prone to shear locking.
- A FEM model of a beam acted upon by pure bending moment would develop spurious membrane strains if the FEM model is prone to membrane locking.

*As far as modal analysis is concerned, what is the effect of the locking phenomenon on the determination of the natural frequencies and mode shapes of the system?*

I'd like to draw a simple model on Plaxis LE designer but I did not find any guideline video that could help me to design it.

The model sample I attached. Please I hope any one can help me as fast as you can

Thanks

Hello everyone

When I plot elements of a FE model with node numbering and multi plots ON, I am also able to see the nodes which are of elements that are opposite/adjacent/not relevant to a particular element of interest. Is there any option in ANSYS APDL to make sure that only the nodes of a particular element is only seen and not that of another element that is adjacent or opposite to that particular element of interest?

N.B: In the attached image, I don't want to see the red-marked nodes.

Hello Researchers,

I am using Gauss Quadrature for numerical integration to obtain the stiffness and mass matrices for a plate element in my FEM code. We know that both these matrices are symmetric. However, I find that due to numerical integration the stiffness and mass matrix turns out to be

**.***asymmetric*Kindly note that the

*is not by any means large. The result of the subtraction of a symmetric matrix from its transpose is a null or zero matrix. If I subtract the stiffness and mass matrix from their respective transposes, the resulting matrix has all the non-diagonal terms of the order 10 to the power of -8 and all diagonal terms are zero (maybe for most cases it can be considered as a zero matrix).***asymmetry**At the point of writing this question, I am suspecting that this discrepancy (i.e asymmetry of the mass and stiffness matrices) is due to the finite precision arithmetic of floating-point numbers. (need your thoughts on whether my suspicions are true)

The end result of not having symmetric stiffness and mass matrices is that the 'eig' function in MATLAB gives incorrect eigenvectors although the eigenvalues are correct.

I would like to know if anyone has encountered such issues and how was it resolved.

I am also attaching a couple of links related to finite precision arithmetic errors below for your reference:

Thank you,

Jatin Poojary

I am using abaqus to model geosynthetic encased stone column (wished in-place). I am new to abaqus so how should I model geosynthetics in 3D and 2D (solid or shell or wire ) and can I get an idea about what type of interaction should I apply in between soil- geosynthetics and geosynthetic-stone column ( in 2D and 3D ).

Hello friends

Nowadays I am trying to use Code_Aster to simulate CABLE . I want to know how to add a force like this F=0.5*velocity^2 on selected nodes?

And how can people add a triangle distributed force on a moving cable whose coordinate is changing with time .

Thanks for your help in advance.

Hi,

I have an experimental tensile curve. This is the engineering stress strain curve right?

I have then converted it to a true plastic strain curve using Abaqus material conversion. Using these values, I have run a tensile simulation.

However, the results that I have obtained seem to replicate more of the true stress strain curve and not the experimental curve.

The load is displacement based where it is pulled by 32 mm which reflects accordingly to the experiment.

I have plotted misses stress vs LE11.(logarithmic strain along x direction ).

The peak stress in the experiment is 50 MPa while the peak stress for the true stress strain is 70 MPa.

I have attached my results below.

From the simulation, I am getting 70 MPa also which is not representative of the experiment.

Is this how its supposed to be or am I skipping something?

Thanks in advance for your help!!

I'm trying to reduce a 3d printer extruder vibration. When the extruder starts to move, vibrates that decrease printing quality. How can I reduce the vibration? I need a procedure to solve the problem using FEM methods like Abaqus. The procedure should contain an optimization method.

Hi,

When I open up Abaqus CAE, I am supposed to see the message area in the lower half of the window below the viewport. But in my system, I am not finding the "Message area" and "Kernal Command Line Interface". The screenshot is attached herewith.

Can anyone guide me where to find it?

Also, in the above link, it is given that the command line area is usually hidden, and we need to click the 3 arrows to get it. But in my case, I am not even finding the 3 arrows.

Please help.

Thanks in advance.

Hi,

I am currently struggling to virtually ream an acetabulum from a segmented hemipelvis. This is required for an implantation of an uncemented cup. As my analysis involves FEA (ABAQUS), I am currently performing the virtual reaming using a sphere. I am currently applying a boolean subtraction operation in ABAQUS to remove the cortical bone (and expose the subchondral bone) by positioning the sphere on the Centre of Rotation of the Hip.

Nevertheless, I seem to get rid of more than desired trabecular bone. Thus, my uncemented cup doesn't seem to have contact with the reamed acetabulum unless the cup is deepened, which leads me to the next question of How to virtually implant an uncemented cup in an already reamed acetabulum?

I have reviewed some literature and some researchers seemed to have used a step in ABAQUS where they perform a displacement control until the uncemented cup is overhanged(certain level of contact is achieved). I haven't used this FEA technique before, so any comments about this is widely appreicated.

I hope I was able to explain myself and this questions aren't too technical to be answered.

Thanks!

Hello everyone,

Hope you are doing great.

I am using coupled temperature-displacement step and coupled temperature-displacement elements as well. I need to use UMAT to model plasticity behavior and fracture. In every run I do, It takes 5-10 days to finish the simulation. I don't know if this is normal for my case study or something is missing?

Usually, I run my job by writing these lines:

---------------------------------------------------------------

abaqus job=xxx.inp user=yyy.for cpus=12 standard_parallel=solver int

OR

abaqus job=xxx.inp user=yyy.for cpus=12

---------------------------------------------------------------

Another thing I'm not sure about is my step setting, which is as follow:

---------------------------------------------------------------

*Step, name=Step-1, nlgeom=NO, extrapolation=NO, inc=1000000, unsymm=NO

*Coupled Temperature-displacement, creep=none, steady state

0.002, 1, 1e-10, 0.002

*Solution Technique, type=SEPARATED

*Controls, reset

*Controls, parameters=time incrementation

5000, 5000, 5000, 5000, 5000, 5000, , , , ,

--------------------------------------------------------------

I appreciate any help you can provide.

Mojtaba Ab

**#Abaqus**

**#fem**

**#FE_Analysis**

**#FEM_Simulation**

**#Plasticity**

**#Fracture**

**#Elastic**

**#Simulation**

I have seen many research papers many people have worked on different software but I am unable to conclude that which is best for research purpose.

I want my ABAQUS script to read values from excel (these values will be used to create the FE Model). After the analysis, I want to extract the results (for example, maximum displacement) and save it in another excel file.

After meshing, I want to create a set comprising of all the nodes on a particular surface of a part (in my case, the top surface of a hollow cylinder). I successfully created the node set in the GUI but for a parametric study, I will be considering many different cylinders. So I want to generalize using a python script.

I wrote a subroutine VDLOAD for dynamic explicit analysis in ABAQUS. The load is spatially distributed as well as varying with time. The subroutine VDLOAD works fine. But the load has two horizontal and vertical components (component1 and component2).

Horizontal component of load = 1*value

Vertical component of load = 0.75*value

Value is defined in the VDLOAD subroutine.

I know that the magnitude data entered in the editor (Attached figure) are passed into the user subroutine in an Abaqus/Standard analysis but are ignored in an Abaqus/Explicit analysis (Abaqus/CAE User’s Guide(6.14) section 16.9.8).

How to model these two components of the load by VDLOAD?

I would be grateful if you guided me through this.

Dear Researchers :

I will appreciate if someone can give me some help with this issue

I already have my 2D-model of a Power Energy Cable in COMSOL Multiphysics.

But so far I haven't been able to model the Heat Transfer and Temperature Distribution in the Cable due to the Joule Effect.

The Cable works under a DeltaV = 25 000 kV, has a Longitude of 1 m , its dimensions are given, as well as the material properties.

But I don't know how to stablish this condition in the model under the 'Heat Transfer in Solids' physics

I also selected the 'Joule Electromagnetic Heating' effect to include into my model, but I cannot solve the Temperature correctly.

How do I have to consider this condition? What Boundary Condition (or Domain Condition) do I have to use on the model ?

Thak you for any help !

Regards ! :)

Dear Researchers, I ask for help;

This is in COMSOL Muliphysics ver.5.6

I am tryring to solve a model of an Energy Power Cable which is burried in the soil, is a 2D model

I choose to couple the phenomena of: -Electrostatics, -Electric Currents and -Heat Transfer in Solids (this last one is coupled using the 'Electromagnetic Heating' sub-module within the AC/DC module).

I already could solve the Electric Potential and the Electric Field (both, E and D) distribution,

But as much as I tried, I cannot understand how to solve correctly the Heat Transfer part of the model

The coupled phenomenon of Heat Transfer is due to the Joule Effect, due to the Electric Current/Voltage passing across the conductor.

When I solve for the Temperature Distribution I get :

- All the model is at the same temperature

- The value of the Temperature is negative, and

- This value is x10^18 K

Defenitevely something is wrong, very likely with the boundary condition of the Heat Source I'am trying to stablish.

It could be an evident-to detect mistake, but I cannot understand it

I am attaching the pictures

The first one is of the view 100% zoomed out, to see the complete geometry (I am including the seccion of the soil in my model),

and the second image is the view zoomed in of the geometry of the Cable

Please, does any know, and can help me, Why I cannot solve this model correctly ?

I will really appreciate it,

Best Regards !

Dear all,

Does anyone ever run site response analysis using Abaqus? Please upload some examples for reffrence.

I did but the results are very strange. I think I have problem with how to assign boudary conditions. I use tie constrain for lateral boudary and dashpot for base boudary.

Thank in advance all.

(my model is attached below)

No matter if I chose topology or shape optimization tasks (or whether they are condition-based or general) I can not see any thermally related variable to select as my design responses for heat transfer related optimization. All variables are all structural parameters (see the picture).

Does Abaqus Tosca work with heat transfer analysis at all? If it does how design responses can be defined as variables like temperature, conduction, etc.?

If you have experience performing thermal optimization using Abaqus optimization module your share of experience will be much appreciated.

I need to model a delamination started from the pick of a transverse crack, how can I model it without using the cohesive zone ( I can't use it due to the lack of properties)

Thank you.

For example I want to model a sandwich composites and I have modelled bi-woven composites in TexGen which I want to import in Abaqus for FE analysis where in the core of the sandwich has to be modelled and I should be able to give interactions between the core and face sheets.

Hi,

I am doing analysis for Reinforced concrete sandwich panel subjected to blast load.After submission, the job aborted due to this error Truss Element 1 has zero length

Need your help.

Thanks.

I need to simulate a Hyper Velocity Impact upon a sensible plate. I would like to split the simulation in two: firstly simulating the part of the plate near the impact (which is subjected to extreme deformation) in Autodyn, exploiting the SPH method; then starting from the results obtained in Autodyn I will conduct the analysis FE involving the rest of sensible plate.

Thus, I need to know how to use the results of Autodyn (in term of displacements/forces/pressures...) directly as the input of FE analysis, which I will do as a "simple " transient structural analysis, to reduce significantly the computational time.

Thank you for your help!

Can anyone share ANSYS APDL code for the Gaussian heat source.

I am using ANSYS 16.2, so I don't have an ACT extension.

I have modeled a flexible multi-body system in Abaqus and I wish to let Abaqus/Explicit solver simulate the system under some actuator loads. Description of simulation steps is as follows:

At the end of "each time-step", some selected results of the simulation (eg. displacements of bodies) are extracted and fed into a MATLAB program to compute the new actuator force which in turn is used as new actuator input for Abaqus simulation.

So after each time-step, Abaqus/Explicit pauses and waits for MATLAB program to run and then receives new inputs for actuators and resumes the simulation for the next time-step.

Attached is a snapshot from ANSYS brochure showing the exact simulation setup where I can insert my FE model into a control loop within SIMULINK editor. I want to know the ways I could do the same thing with Abaqus. Any help would be greatly appreciated.

I am trying to estimate the thermal stresses that develop during the sintering of yittria stabilized zirconia (YSZ) cylindrical pellet containing Gd2O3 sphere, from room temperature to 1500oC with a heating rate of 10oC/min and holding time of 20 min, using the heat transfer in solids interface, solid mechanics interface, and coefficient form PDE interface.

Problem description and simulation files are attached for your reference

Hey guys,

I am attempting to model the installation of a helical pile into sand using Abaqus CAE (explicit). I am using a CEL model with a rigid pile and Eulerian sand part.

Every time I run the job, the sand part 'explodes' and has very large deformations. I have attempted to rectify this problem via the following trials:

-assigning cohesion to the sand;

-applying a pressure to the sand;

-beginning the installation with the pile already penetrated into the sand part.

Through an exhaustive trial-and-error process, I found that I have solved the exploding sand problem by changing the 'hard' normal contact interaction to a 'linear' contact interaction. However now, the history outputs show no plasticity/plastic deformation! This is kindof important as I am interested in finding the installation disturbance effects of screw-pile installation.

Is anyone aware of what I can do to accurately/realistically model the installation disturbance effects of a screw-pile being installed into sand? I am happy to provide any more information as needed.

Thanks!

Hello all!

How to model a composite model with a high strain rate (explicit dynamic analysis) in ANSYS or Ls-Dyna.

I am trying to predict the preload loss in a bot using the analytical relation ( Equation-(28)) given in the paper: . I am not sure How to implement the analytical relation in algorithm. The preload loss seems not to effect any parameter in the Eq-28 except sliding speed to rotational speed ratio. But that dependency of bolt can be neglected based on the assumption of Eq.28 .

It will be of great help if you could suggest something here.

Thanks!

Dear ANSYS users,

I am doing FE analysis of RC beam using ANSYS APDL VI9, where I assigned force-displacement (bond-slip) to COMBIN39 based on CEB-FIP 2010 MODEL CODE, to model the steel-concrete INTERFACE. After completion of simulation, I wish to determine the interface bond stress at each load step and the respective slip values. Kindly suggest your reply how can I find these values, so that I could draw load VS slip curves.

Thank you,

Hi. I am doing non linear FE analysis using a new material beam under flexural 2 point loading using ANSYS. I have defined a bilinear material model. The solution has converged. In results I am getting good stress strain curves (as expected, i.e slope decreasing post yield). However the load displacement curves show an increase in stiffness pattern. Please help me to correct the load displacement curves.

Hello everyone, hope all is good.

I want to analyse multi-phase fluid flow through pipe, which software is best to do so ?

Please share any Example, Tutorial or any article related to CDPM. For a 3D Pushover analysis.

Thanking in anticipation!

Greetings to everyone,

Our team is currently working on the development of a VUMAT code in Abaqus for composite modelling using the Puck's failure theory as damage initiation criteria. Currently we manage to develop 6 different algorithms (4 on literature and 2 of our own) to find the fracture angle of any state of stress in an accurrate and efficient manner.

My question is related to the post damage behavior. Let's assume that a material point reach the Puck's failure initiation condition for an angle of -58° in matrix compression. It is clear that the material can resist further load in matrix tension and we need to degrade the stiffness matrix and so on. However, for this post damage stresses the fracture angle needs to be set to -58° or do we need to still look for the fracture angle? It is also known that the most critical angle depends on the state of stress and if we set constant from that point on are we understimating the damage?

If you need further instructions or the question is not clear enough please let me know. I'll be glad to share more details in case they are required.

Thanks in advance for your aid and support

Is the stress throughout the thickness of the shell element the same?

I learned that transverse shear stresses are accounted for in SHELL181 but I also read that stresses in shells along the thickness are assumed to be constant in linear analysis.

Hello

I want to add thermal convection load on specific area of concrete volume.

it asks for film coefficient which is a constant value but the bulk temperature has no. of values that i have as excel file.

Can i import that excel file in ANSYS APDL or can how can i add tabular data in ansys apdl?

TIA

What are the shape functions of CST triangular and Q4 rectangular element models in terms of natural coordinate system (N.C.S) with (s,t) not with (x,y) in software programs as ANSYS mechanical APDL?

Why does normal bending stress/flexural stress value (Sx) just direct below a concentrated load of simply supported beam which is compression stress higher than the hand calculation Exact solution (theory of beam stress) in value in ANSYS APDL with any element type (Area type) of FE modelling 2D, solid 182 or 183 quadrilateral or triangle?

- Compression stress in Exact solution (-4687.5
*Kpa*). In ANSYS (-7077.26*Kpa*). - Tension stress in Exact solution (4687.5
*Kpa*). In ANSYS (4490.11*Kpa*).

I want to analysis of 2D FE modelling beams cantilever/simple support in ANSYS, then compare it with exact solutions (elementary) such as deflection or stresses, however what element types (solid 182 or 183) in ANSYS Mechanical APDL are the best and appropriate? While the results will be close?

Usually, in COMSOL MultiPhysics, there is an option to choose the parameter value from material properties. For example, for choosing Young's modulus value E in the solid mechanics module, one can select "

*from material*" or input the value. Here one can simply define more than 1 domain having different values of E. But if there is no such option how can I access the material property. (I have two domains with different material property value).Both Link180 and SOLID185 elements have 3 degrees of freedom each (translation along the x, y and z) with no rotation allowed.

But why do both behave differently under applied load?

Why does SOLID185 "BEND" although it does not have translational degrees of freedom

But LINK180 does not bend under applied loads, like it deforms down but the element itself does not bend (the element stays straight without any curving)

Finite element model.

is there sensor history output for energy ALLKE and ALLPD in abaqus 2020?

is there any one help me

I do not understand how to provide

**pinned support to the rigid bodies**. ABAQUS suggests that either rotary inertia must be defined at the reference nodes or all of the rotational degrees of freedom at the reference nodes must be constrained. What I do not understand is what values of**rotary inertia**is to be used in this case. Is there**any other way to do pinned case**in ABAQUS/EXPLICIT that I am missing? Thanks!Hi, I am trying to create a computation model of acoustic plane wave propagation through multiple layers of fluid. What should be the appropriate boundary conditions in my fluid-fluid interface? Thank you.

want to make a fatigue simulation on some mechanical parts like Gears, Bearing, and gear housing.
please assume 2 gears in contact.when they Are rotating under constant torque and velocity the stress in every node is unique and varies every time.
I can define a signal for a node based on time stress (\Sigma (t)) of the node but I cannot do that for the millions of them.
Is there any solution for this problem?
I saw some tutorial videos but all of them using one or two signals and applying to all elements but I cannot do that. Stress in posision1 (X1(t),Y1(t),Z1(t)) do not change the same as posision2 (X2(t),Y2(t),Z2(t)). But in tutorial videos stress in po1 is a constant scale of po2 in every time and the scale stays constant.
please help me to solve that I have many problems with that.

Hello,

I am looking for a research partner who has ample experience in the

**FE modelling**for*structural retrofitting*with any commercial software and has**access**to it. You need to conduct series of FE modelling (in ABAQUS/ANSYS/DIANA/any platform of your choice) for retrofitted structure (beam/columns) and verify the experimental data (experiment already done). It's not a large task, once material model is verified you need to run few simulations. I am expecting article writing assistance as well.If you are interested, please send me an email at imrosebin.muhit@uon.edu.au with your CV. Please let me know your experience regarding FE analysis.

Cheers!

Is there any software that can provide me the stiffness matrix of a structure?I know that i can work on Abaqus or Ansys for example,but I want only the stiffness of the model without solving the final system Ax=b.Does any know how can I obtain the stiffness?Also can Gmsh provides me the stiffness file except the mesh file?

Is there any open source software that can be used to segment image data (dicom) and the segmented data can be exported as volume or mesh data for further FE analysis?

Hi Everyone,

My attempt to use the drapability and stretching behavior of knitted composites(just fiber without matrix) in die forming. At this moment, I am only interested in the behavior of the fiber.

I ran 2 models (geometrically, constraints and interaction are identical).

Job 68-

Material model used (Steel with plasticity defined).

Results: Are converging. The behavior is as expected.

Job 69- Material model used (Carbon fiber-MAT-1 in .inp and material orientation defined based on texgen software algorithm). Added orientation by calculating the normal for each element using the node data. I have defined the material parameter based upon the property sheet from attached Hexcel-tow data.

The error I get is ratio of deformation speed is too high. I have tried a number of possibility as mentioned in this forum earlier. Any help would be highly appreciated:-)

-Sangram

How should I create a system in ABAQUS that consists of rigid parts (parts must be connected with pins like truss systems)?

I use some techniques but I want to know other possible techniques..

Direct or tricky methods I can accept.. For instance material usage with very high elasticity, or manipulated Poisson's ratio. I can use game engine for this but I want to use Abaqus?

In literature, Anterior longitudinal ligament (ALL), Posterior longitudinal ligament (ALL), Supraspinous Ligament (SSL), Interspinous Ligament (ISL), Intertransverse Ligament (ITL), Facet Capsular Ligament (FCL), Ligamentum flavum (LFL) ligaments are modeled with the whole lumbar vertebrae. However, I couldn't reach the exact numbers of them in the model, repectively. Do you have any information about this? Could you give me a suggestion to solve this problem?

Hello,

This is propably a primitiv question but I am trying to figure out how to implement a moment at the tip of a (for simplification) beam around the z axis. It should follow the nodal rotation in a dynamic case. When using Abaqus this is quite simple: I get a reference point in the middle of the surface (end of beam) that is supposed to rotate and couple it to the mentioned surface, with a Coupling card. Then I load the reference Point with a Moment (CLOAD)

.....

*nset, nset=end

2, 4, 6, 8, 2, 4, 6, 8, 12, 13, 14, 18, 19, 20,

*nset, nset=RP

711

*SURFACE,NAME=moment,TYPE=NODE

end,

*COUPLING,REF NODE=711,SURFACE=moment ,CONSTRAINT NAME=C1

*KINEMATIC

....

*STEP

*DYNAMIC

....

*CLOAD

RP, 6,10

*STEP END

When doing this similar in CalcuiX nothing happens for the dynamic case. I am able to do it in a static calculation though!

I also tried loading the moment on the nodes of the surface directly or just around the middle line. Also nothing happens. When loading a force though it works.

I am quite new to CalculiX and at our department nobody worked with it before.

I would really appreciate if somebody could help me and give me a hint.

Thank you very much!