Science topics: FE Analysis
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# FE Analysis - Science topic

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Questions related to FE Analysis
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can any one explain the procedure of nonlinear finite element analysis of concrete beam with reinforcement, using ansys drucker Prager model or any other way? How to find the ulimate load capacity of concrete beam.
Sir , I had modeled RC concrete beam 5m length and 300mm X 600mm Cross-sectional with Main reinforcement and stirrups in anysy workbench according to Dr. Dydlo vedio. I had applied -80 mm displacement to find the ultimate load carrying capacity. I had use the apdl file given by Dr Dydlo vedio.
Help me in the material property definition in the APDL command according to the Multilinear Elasticity material model and Drucker-Prager Model.
How can I get actual behaviour of concrete under failure load?
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I have a model that I am using to validate mechanical testing. I have validate three models up to 5% with a 1.5mm mesh. I have performed a mesh sensitivity study and found that smaller mesh sizes change my results. My model has the correct boundary conditions, correct material properties, etc.. I am trying to publish my paper and wondering if it's common that you can validate a model without mesh sensitivity? If it is not, what is the proper way of performing mesh sensitivity on a corrugated core? I don't want to go smaller in mesh because my models is no longer validated. Thank you.
@kristaq hazizi, thank you for your response and guidance. Your reply has given me new guidance on my problem.
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Can anyone please tell me in detailed explanation what is the difference between the joint and the connection in steel joint?
given that :
joint rotation = total rotation of the beam-end - beam elastic deformation - column elastic deforamtion - block rotation
connection rotation = joint roation - column web in plane rotation + column elastic deformation + block rotation
Those equations are taken from the litterature
In the context of steel structures, a joint refers to the point where two or more structural members are connected together, while a connection refers to the actual mechanism or means by which those members are joined.
The joint rotation is a term used to describe the rotational movement or displacement that occurs at the joint between two connected members, such as a beam and a column. It represents the relative rotation between the connected members caused by external loads or deformations. The joint rotation is influenced by various factors, including the stiffness of the members, the type of connection, and the applied loads.
The total rotation of the beam-end refers to the rotation experienced by the beam at its end due to external loads. This rotation is directly related to the applied moments and forces on the beam and can be calculated using structural analysis methods.
The beam elastic deformation refers to the rotational displacement of the beam caused by its own flexibility or elasticity. When a beam is subjected to external loads, it undergoes elastic deformations based on its material properties and cross-sectional characteristics.
The column elastic deformation refers to the rotational displacement of the column caused by its own flexibility or elasticity. Similar to the beam, a column can also experience elastic deformations when subjected to external loads.
The block rotation refers to the rotational displacement of the block or base on which the column rests. It occurs when the column base is not completely fixed and allows for some rotation. The block rotation can be influenced by factors such as the base connection type, soil conditions, and column loading.
The connection rotation is the overall rotational displacement or movement of the joint as a result of the connection and its interaction with the connected members. It is calculated by subtracting the column web in-plane rotation, adding the column elastic deformation, and adding the block rotation from the joint rotation.
The column web in-plane rotation refers to the rotational displacement of the column web (the vertical plate connecting the column flanges) caused by the applied loads and the interaction with the connection. This rotation can occur when the connection transmits forces and moments that induce twisting or rotation of the column web.
To summarize, the difference between joint rotation and connection rotation is that the joint rotation represents the relative rotation between the connected members caused by external loads, while the connection rotation takes into account additional factors such as column web in-plane rotation, column elastic deformation, and block rotation. The connection rotation provides a more comprehensive understanding of the overall rotational behavior of the joint and its connection.
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i am uploading this files, and I appreciate if anyone would accept to check it for me, I am trying to model a model of beam to column joint but the beam is bolted to the web column, I am facing a problem in the step of bolts pretensioning, it does not converge from the first increment, it indicates singularity warning along with zero pivot warning in the region of the bolts. I am confused because it's the same value of the force and the same bolts as another model i did in the past with the beam bolted to the flange, and it worked perfectly fine,only the materials are changed because of the experimental work. Waiting for any reponse.
Hello Sara, when I checked your model I didn't find any contact definition between surfaces, the analysis is very sensitive to the surface's contacts. So, I advise you to use surface-surface contact and define all contacts through your model, especially those between the bolt and the other component surfaces. I did a writing mistake for the materials, but when we define material plasticity the first value should be the yield stress value not 0.001.
I recommend you a video on youtube with a close model to yours (https://www.youtube.com/watch?v=mQPJmyAM6pc)
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Dear Researchers :
I will very much appreciate the help.
I have a 2D model in COMSOL. It's a plate, made of Polyethylene. An AC Voltage is applied on the upper electrode, the lower electrode is on V=0 (ground)
The sinusoidal function of the voltage is : Vo*Sin[wt + phi] where phi = 0 and V_o is equal to 2.4 kV
I am attaching an image of my 2D Geometry
I am solving the model in two steps
Step 1 : Using a Time Dependent Study (just to solve the physics of the electric currents module)
Step 2 : A stationary solver, to solve the Heat Transfer in Solids part.
I used the Multiphysics interphase of Electromagnetic Heating
I can correctly solve the Electric part of the model
But for the temperature, this is the graph that I get, which of course is not correct
Does someone might know where the mistake might be ?
Best Regards all :)
Dear Mustafa Shqair I didn't see your reply before sir, I will review it and see if with this information I can solve the problem.
Thank you !
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I am currently working on a model which has steel beam whose one end is embedded in a concrete wall. The cantilevered end of steel beam is subjected to cyclic shear load. I am struggling to model the interaction between the portion of the steel beam embedded and the concrete. What will be the appropriate way to do it?
I tried by using 'hard' contact in normal direction and using coefficient of friction of 0.45 along tangential direction. The results obtained are different than experimentally observed.
Now, I am thinking of using surface based cohesive interaction, but I don't have necessary parameters which is needed for defining traction-separation and damage. Is there is a rational way to calculate these parameters without doing experiment?
Any suggestions and help will be appreciated.
You can use the inverse method by minimizing the difference between the numerical and experimental results to find the constants of the cohesive zone model
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Dear amazing researchers,
I am working on a nonlinear FEM problem and using Python for coding.
To get the nodal values of the field variable, I have to solve a system of linear equation. In matrix notation, [A]{x}={b}, where [A] is a sparse-matrix (a lot of zeros away from main diagonal), {b} is the right hand side vector.
One trivial solution is {x}={b}/[A], but it is computationally heavy when needs to be done many times and [A] is large.
Lets take a simple example:
A = [[5, 2, -1, 0, 0],
[1, 4, 2, -1, 0],
[0, 1, 3, 2, -1],
[0, 0, 1, 2, 2],
[0, 0, 0, 1, 1]]
and b = [ [0],
[1],
[2],
[2],
[3]]
To store the complete sparse-matrix is waste of memory when a large number of element values are zero, so I wrote a code to store the matrix in a compact form, which stores the non-zero diagonals in every row.
[Ac]= [[ 0, 0, -1, -1, -1], [ 0, 2, 2, 2, 2], [ 5, 4, 3, 2, 1], [ 1, 1, 1, 1, 0]]
There is a function in "scipy" library. It is scipy.solve_banded(), which takes the "Ac", and "b" as arguments and return the solution {x}.
Could anyone help me to find out the algorithm behind scipy.solve_banded() function?
I will be very thankful for your help.
Assuming Ac is banded matrix structure, a possible algorithm to perform LU Decomposition on Ac could look like this:
1. Initialize two compact matrices Lc and Uc to store the lower and upper triangular parts of the decomposition. These matrices have the same structure as Ac.
2. For each column j:a. For each row i from j to N (N being the size of the matrix): Compute the sum of products of corresponding elements of the i-th row of Lc and the j-th column of Uc. This corresponds to the dot product of the i-th row and j-th column of the full matrices L and U. Subtract this sum from the i,j-th entry of A (which is represented in Ac) to get the i,j-th entry of U (to be stored in Uc).b. For each row i from j+1 to N: Compute the sum of products of corresponding elements of the i-th row of Lc and the j-th column of Uc. This again corresponds to the dot product of the i-th row and j-th column of the full matrices L and U. Subtract this sum from the i,j-th entry of A (which is represented in Ac) to get the j,i-th entry of L (to be stored in Lc).
3. Return Lc and Uc as the compact representations of the lower and upper triangular parts of the decomposition.
*** Assuming that no pivoting is required. If pivoting is required, the situation gets significantly more complicated for a banded matrix.
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Hello everyone,
i have i very simple model, of beam to column steel joint, i have modelled it perfectly but the solution is diverging from the first attempt, i really could'nt understand where is the problem because i have zero warining except for some distorted element but not so much important.
Is is possible for someone to help me, if yes please write your email in the comments and i will send you the necessary files of abaqus ( i work with abaqus 6.14).
using a reference point which is appropriately coupled with the target area is a better way than imposing loads directly on the element nodes.
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Dear everyone, now I have got the principle strain tensor (or increment) of a material point, as well as the reference hardening curve of the material (along the rolling direction) together with the anisotropic yield stress ratios. I failed to calculate the corresponding equivalent stress. I know that if the material is isotropic, the situation is very simple because I can get the equivalent strain first (igoring the elastic strain), and then find the corresponding yield stress from the hardening curve. But what can I do under the Hill anisotropic plasticity? Can anybody help me with that? Thanks so much. p.s., for simplification, the elastic strain can be ignored.
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Hello
I have an FE model (linear elastic material, homogeneous) using shell181 elements. The structure is subject to constant acceleration and undergoes a static analysis (antype,static).
About shell,mid and keyopt(8), Ansys manual reports:
KEYOPT(8) = 2 stores midsurface results in the results file for single or multi-layer shell elements. If you use SHELL,MID, you will see these calculated values, rather than the average of the TOP and BOTTOM results. You should use this option to access these correct midsurface results (membrane results) for those analyses where averaging TOP and BOTTOM results is inappropriate; examples include midsurface stresses and strains with nonlinear material behavior, and midsurface results after mode combinations that involve squaring operations such as in spectrum analyses
My midsurface results are not the average of top and bottom results, despite linear material and static analysis.
Just as an example for one element, I have for Von Mises (PRETAB):
ELEM STOP SMID SBOT
41848 0.20593E+008 0.60772E+007 0.26821E+008
where SMID, Von mises at shell,mid location, clearly is not the average between top and bottom.
So, why is this behavior happening given that I have linear material and no response spectrum analysis?
Mathias
Von Mises is a nonlinear function of stress components, which are the output averaged.
The average of von Mises is, in general, not equal to the von Mises of average stresses.
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Hello good people
I am simulating multipass multilayer additive manufacturing with ANSYS transient-thermal module. The problem is that the Gaussian heat source (APDL code) works fine with the first layer, but when it comes to the second layer, it does not work. The heat flux does not even initiate for the second layer. I tried generating the code with a different coordinate system for the second layer, but that didn’t work either. I also tried incorporating the ‘z’ or the height of the second layer in the equation. Unfortunately, it didn’t work. But when I put the heat sources for both layers in the same time step, it works for both layers; they don’t work in different time steps.
How can I modify my code so that it works for the SECOND LAYER in the SECOND TIME STEP or any layer after the first layer?
The APDL code is mentioned below-
*DIM,HEAT_FLX1,TABLE,6,24,1,,,,0
!
! Begin of equation: 4e7*exp(-3*(({X}-0.05)^2+({Y}-0.01*{TIME})^2)/0.005^2)
*SET,HEAT_FLX1(0,0,1), 0.0, -999
*SET,HEAT_FLX1(2,0,1), 0.0
*SET,HEAT_FLX1(3,0,1), 0.0
*SET,HEAT_FLX1(4,0,1), 0.0
*SET,HEAT_FLX1(5,0,1), 0.0
*SET,HEAT_FLX1(6,0,1), 0.0
*SET,HEAT_FLX1(0,1,1), 1.0, -1, 0, 0, 0, 0, 0
*SET,HEAT_FLX1(0,2,1), 0.0, -2, 0, 1, 0, 0, -1
*SET,HEAT_FLX1(0,3,1),   0, -3, 0, 1, -1, 2, -2
*SET,HEAT_FLX1(0,4,1), 0.0, -1, 0, 3, 0, 0, -3
*SET,HEAT_FLX1(0,5,1), 0.0, -2, 0, 1, -3, 3, -1
*SET,HEAT_FLX1(0,6,1), 0.0, -1, 0, 0.05, 0, 0, 2
*SET,HEAT_FLX1(0,7,1), 0.0, -3, 0, 1, 2, 2, -1
*SET,HEAT_FLX1(0,8,1), 0.0, -1, 0, 2, 0, 0, -3
*SET,HEAT_FLX1(0,9,1), 0.0, -4, 0, 1, -3, 17, -1
*SET,HEAT_FLX1(0,10,1), 0.0, -1, 0, 0.01, 0, 0, 1
*SET,HEAT_FLX1(0,11,1), 0.0, -3, 0, 1, -1, 3, 1
*SET,HEAT_FLX1(0,12,1), 0.0, -1, 0, 1, 3, 2, -3
*SET,HEAT_FLX1(0,13,1), 0.0, -3, 0, 2, 0, 0, -1
*SET,HEAT_FLX1(0,14,1), 0.0, -5, 0, 1, -1, 17, -3
*SET,HEAT_FLX1(0,15,1), 0.0, -1, 0, 1, -4, 1, -5
*SET,HEAT_FLX1(0,16,1), 0.0, -3, 0, 1, -2, 3, -1
*SET,HEAT_FLX1(0,17,1), 0.0, -1, 0, 0.005, 0, 0, 0
*SET,HEAT_FLX1(0,18,1), 0.0, -2, 0, 2, 0, 0, -1
*SET,HEAT_FLX1(0,19,1), 0.0, -4, 0, 1, -1, 17, -2
*SET,HEAT_FLX1(0,20,1), 0.0, -1, 0, 1, -3, 4, -4
*SET,HEAT_FLX1(0,21,1), 0.0, -1, 7, 1, -1, 0, 0
*SET,HEAT_FLX1(0,22,1), 0.0, -2, 0, 4e7, 0, 0, -1
*SET,HEAT_FLX1(0,23,1), 0.0, -3, 0, 1, -2, 3, -1
*SET,HEAT_FLX1(0,24,1), 0.0, 99, 0, 1, -3, 0, 0
! End of equation: 4e7*exp(-3*(({X}-0.05)^2+({Y}-0.01*{TIME})^2)/0.005^2)
!-->
sf, s1, hflux, %HEAT_FLX1%
Thank you for your response. I created a new parameter, 'time_elapsed' as you recommended here. Unfortunately, the laser source still works only on the first time step. It doesn't work in any other time step, even if I select it to run on other time steps specifically.
Could you please suggest how you would do it?
Best,
Tan
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"Error in job messaging system: error in connection to analysis".
Sometimes I get this error while running multiprocessor dynamic explicit large analysis at random stages of the analysis. It might happen a couple of times. In case of running multiple jobs and one of them aborts for this reason then all the jobs get aborted at the same time. When resubmitting the job, the job might get completed without having edited the model at all. Any ideas? I have attached the status file.
SOLUTION:
You can fix this by disabling the windows feuture to lock the compure after an idle period of time. In general avoid locking your PC while running an analysis. Stable internet also helps avoiding this kind of error.
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Hello ResearchGate,
I'm simulating a blanking process in 2D using Abaqus Explicit with ALE. When the Johnson-Cook criterion is satisfied, elements start to be deleted, thus simulating the fracture at the end of the process. However, no matter how much I try to initially distort the mesh so that it gets more structured by the time fracture starts, the element deletion propagates "diagonally through the elements" (see attached screenshots), which leaves some of the not deleted elements connected by just one node (again, see attached screenshots). This stretches those elements to the point where my stable time increment gets pretty low, my burr is distorted and large, unrealistic stresses appear. I've tried to make the mesh finer, which hasn't really solved the problem. I've also tried to activate DELETE DISTORTED ELEMENTS, but this option doesn't seem to work, as the elements get stretched but their characteristic length remains large, as well as their area. I've tried applying the minimium dt option of this tool with no success (as the only parameter that seemed to be altered by these distorted elements was the stable dt).
I've attached a couple of screenshots that showcase the problem. If anyone knows a workaround or has any suggestion they will be very welcomed.
Have a nice day :)
When using Abaqus or other finite element analysis software, it is not uncommon to encounter elements that become highly distorted and remain connected by only one node. This can occur for various reasons, such as meshing errors, modeling inaccuracies, or material instability.
To address this issue, you can try the following steps:
1. Check the mesh quality: One of the primary reasons for highly distorted elements is poor mesh quality. Ensure that the mesh is refined in areas of high-stress gradients and curvature. This can be done using adaptive meshing or manually refining the mesh.
2. Adjust the element type: Different elements behave differently under varying loading and boundary conditions. Switching to a more suitable element type may help reduce element distortion.
3. Consider changing the material model: Material instability can also cause element distortion. Try using a more robust material model that is better suited to the properties of the material being analyzed.
4. Increase the number of integration points: Sometimes, distorted elements can be a result of insufficient integration points. Increasing the number of integration points can help resolve the issue.
5. Use element deletion: If an element is highly distorted and causing convergence issues, it may be necessary to delete it. This can be done manually or by using the element deletion feature in Abaqus.
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Hi,
I have exported the mass and stiffness matrices for a 2D euler-bernoulli beam element (B23 in ABAQUS). These elements have three degrees of freedom for each node (two translation, one rotation), therefore, for a single element I would've expected a 6x6 matrix for both matrices, however, I have an 8x8 matrix for both.
Can anyone tell me where these extra DOF are coming from?
I have attached the input file I used to extract the matrices as well as the mass and stiffness matrices. The beam material properties are:
L = 1m
b = 0.01 m
h = 0.01
E = 70e9 Pa
rho = 2700 kg/m^3
v = 0.3
.dat file reports that:
NUMBER OF ELEMENTS IS 1
NUMBER OF NODES IS 3
NUMBER OF NODES DEFINED BY THE USER 2
NUMBER OF INTERNAL NODES GENERATED BY THE PROGRAM 1
TOTAL NUMBER OF VARIABLES IN THE MODEL 8
From Abaqus theory manual (sect.3,5,3. Euler-Bernoulli beam elements, Interpolation): “To eliminate the unwanted axial strain constraint, in Abaqus the stretch at the node of each such element is taken as an internal variable, local to the element (a third internal node is created for this purpose, and so it is not shared with neighboring elements.)”
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Help i am getting the following error message in abaqus
**WARNING: Surf-1 is ambiguously connected at node ###. This surface cannot be used with *CONTACT PAIR. ***ERROR: 1 improperly defined surface(s). Please check your surface definitions. Make sure that all surface normals point outward.
Note:
The mesh is an orphan mesh and is generated outside ABAQUS.
The mesh is fine and has a huge number of elements.
Element typr for the mesh is C3D4
i have defined the surface using ABAQUS CAE and it was generated automatically using the following commands
*elset, elset=surf-1-S1-1
*elset, elset=surf-1-S2-1
*elset, elset=surf-1-S3-1
*elset, elset=surf-1-S4-1
....
*surface,type=element,name=surf-1
surf-1-S1-1,S1
surf-1-S2-1,S2
surf-1-S3-1,S3
surf-1-S4-1,S4
As you will see, i have followed section 2.3.2 Element-based surface definition in abaqus user's guide.
if you read "Creating surface facets by specifying solid, continuum shell, and cohesive element faces" you will see i have followed it.
So what is the issue here?
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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.
Thank you for your guidance! You helped me a lot in understanding the problem. I will try to include the buckled geometry of the shape for further analysis and in the next experiment, I will definitely use strain gauges at critical points.
Best regards,
Didar Meiramov
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Greetings researchers!
I am using FEM to obtain the time response of the nonlinear forced vibration of plates. I am using plate elements based on Reddy's HSDT and Newmark time integration in conjunction with the Newton-Raphson iteration to obtain the time response.
It is well known that multiple steady-state solutions can exist in the case of nonlinear forced vibrations. Also, all steady-state solutions are not stable. In practice, unstable solutions are not realizable and the system assumes any one of the stable solutions depending on the initial conditions.
I was curious to know whether the FEM predicts only stable steady-state solutions. Or does it predict stable and unstable solutions and the stability of the predicted solutions needs to be determined through other means?
Thank you for your valuable time.
With best regards,
Jatin
I think Praveen meant stable solutions and not steady. To get unstable solutions you can integrate backward in time or use continuation methods to trace steady-state stable and unstable solutions including bifurcations.
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Dear Researchers,
As you know, it is possible to generate the code of modeling in SpaceClaim and FE analysis in Ansys. However, I do not know how can I connect the codes of these sections.
I Ansys Apdl, it can be generated completely but I do not know how can I do it in Ansys workbench.
Thank you for spending time and responding to my question. I will read and watch your references. That would be helpful for keeping on my research.
Regards
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i've been trying to evaluate the strain energy consumed in the ring shown in image and i've marked the (energy) option at the F-output before submitting ......... however, there is no clear data shown in the results monitor
Any suggestions ????
You are welcome.
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I am trying to simulate the knee joint and I have a concentrated force applied on the femoral part of the model, the model also has a kinematic constraint that allows for the femur to flex and extend ie displacement boundary condition and the tibia part is fixed. the aim is to include the anterior-posterior motion of the tibia as well
The load is time based as well as the displacements. when I run the simulation, with the required load the stress generated is the same as when 4x the initial load is applied. How can I fix this?
Please find attached the cae file for this model
As mentioned by Nils Wagner, you'd better share .inp file, because your .cae file can only be used in ABAQUS/CAE 2021.
Btw, are the stresses any meaningful? Applying concentrated force sometimes results in local stress rise around the loading node, while the other nodes does not affect by.
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I have done a comparison by applying the hydrostatic pressure on the middle and top of the shell curve surface (Section Assignment: Shell offset = Middle or Top surface in Abaqus). In the case of the middle surface minimum deflection is 6.115 mm, but in the case of the top surface, the minimum deflection is 12.18 mm. The curve plate is simply supported from three sides.
I have attached images of the results.
Could anybody tell me, which one is correct and why?
Thank you very much
Zuffain Hussan Can you share the underlying Abaqus models (.inp)?
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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
I assume that you are only modelling heat transfer in the material by conduction. There will be convective currents inside the melt pool, so a model based upon conduction alone will not correctly predict this behaviour. Some publications have described the use of an increased thermal conductivity in material that has melted to attempt to model the increased heat transfer. However, the latent heat could be incorporated via an increase of the specific heat capacity in a temperature range based around the melting point. Some FE codes provide a latent heat option with a temperature range for the release.
Regards,
Simon
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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.
I found the answer. The problem was that I manipulated with stresses after the calculation of the ddsdde and a stress vector. I solved the problem by putting the stress vector calculation at the end of the subroutine. In other words, "the correct stresses" are at the beginning.
If you have similar issues, let me know.
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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
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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 presume, you are using concrete with GFRP on the bottom face to avoid tensile failures. Which material model is used for concrete ? There is a large stiffness contrast at the interface of concrete and loading plate. Given the choice, I would for coarse mesh at the loading place, and surrounding concrete. Another way is to provide graded stiffness at this interface. This is by increasing the E value of concrete layers, at top most face, and reducing by 10% to 25% based on mesh size. This shold give smooth stress flow from loading plate to concrete, and analysis may not terminate. Try and give feedback.
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I am New to MDS simulation which software will be open source and free tutorial available for beginners?
Hi,
I have a little bit of MDS experience in 3 different software, so my opinion is based on these three:
1) Rich learning resources and analysis modules: Amber simulation engine
2) Beginner-friendly, good learning resources, and free: Gromacs
3) Pythonic and reasonable beginner-friendly but scarce analysis modules: OpenMM
In the case of Amber, the simulation engine is not free, while the rest of the resources are free, and its learning curve is steep. The various input files are difficult to understand in the beginning. However, Its analysis module contains almost everything. Plus, managing multiple trajectories/topologies during analysis is very easy.
Gromacs is easy to learn, however, the analysis module is not as rich compared to Amber. If you can somehow learn MDAnalysis (a python based MD analysis suite), then you can do almost everything required to analyze the trajectories.
For openMM, it is more suitable to develop and test new theories and force fields, however, you can run simulations using this.
There are other tools as well, like NAMD, CHARMm, etc but I don't have any experience in them, so I cannot comment.
Good luck.
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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
Three-dimensional (3D) eight-node solid C3D8 elements for concrete &
T3D2 elements for reinforcement are adequate to get the damage mechanism on the type of testing.
For a 4-point bending test, a numerical verification of CDPM in ABAQUS based on experimental results can be found here:
Bests,
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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!
Can you share your finite element model?
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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.
it all depends on the objective of the analysis: if the bolt has only to be modeled to include the effect of its pretension, the axisymmetric option seems reasonable. If the goal is to analyse the screw, a 3D model is obviously necessary.
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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 ?
What you need to do is to couple the "Magnetic Fields" interphase (not the "Electric Currents" interphase) with the "Heat Transfer in Solids" Interphase, through the Multiphysics "Electromagnetic Heating".
And then you should be able to couple all the phenomena correctly.
Regards !
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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.
Nils Wagner Here's a sample job that I created, which should be enough to understand the situation. There are 3 steps with loads (Step-1, Step-2 & Step-3) and 2 dummy steps (Step-1_D & Step-2_D) which only exist to deactivate the loads from the previous step.
This is not the actual model that I am working on, since I don't think I am at a liberty to share that. But the problem is exactly the same. Here the loading is in 3 different directions, which need to be evaluated independently of each other. To save on computation time, I am trying to do them as different Steps in the same analysis rather than create a separate analysis for each direction, but it does not seem to be working out very well so far.
Please let me know if you would like any more details.
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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).
1. Can this be considered to be strictly true?
2. 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?
Dear Jatin,
Not always does a finer mesh result in a more exact solution. A mesh convergence study should always be performed to guarantee the descending trend of the error as the mesh size gets smaller.
Having this verified, yes, a finer mesh reduces the stiffness of the model. Because FE approximates the the PDE solution by forcing the element into specific modes of displacement which yields a stiffer element. But as the element size decreases, the FE solution converges to the analytical solution of PDE.
Eigenvalue can be physically interpreted as how stiff the structure is in the eigenvector direction. So it follows the same pattern as stiffness.
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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
For what kind of materials?
Linear elastic: Its 3D plot has no special meaning
It is significant for materials with anisotropic and nonlinear properties.
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I want to do FEM analysis on cold extrusion.
hi every body i will appreciate that if you introduce me screw design software
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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.
Dear all,
Probably it is too late to respond to this question. However, I wanted to put my two cents here.
Selecting interior nodes is always a challenge and simply selecting a surface and the nodes attached to a surface is not always going to work. The best way of selecting nodes is selection based on a coordinate system and a geometry referred to that coordinate system (as also suggested by
Claudio Pedrazzi
). In Mechanical (by default) you can select nodes based on a cube geometry which is related to a Cartesian coordinate system (in the background). You can developed algorithms that uses different shapes e.g. cylinder, sphere and etc. based on either Cartesian or Cylindrical coordinate systems.
I developed an ACT sometimes back that enables selecting nodes in ANSYS Mechanical based on different shapes and coordinate systems. This ACT is available in ANSYS app store right now. I put a pdf document here hat shows the ACT capabilities.
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Hello everyone,
I found in some papers that the bolt joint can be conveniently modeled using the thin layer element which has been integrated into many commercial FE packages.
In the tutorial Modeling the dynamics of mechanical joints (S. Bogradet al, 2011, MSSP), 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?
My final goal is to simulate how the pretension of the bolts affects the dampings of different vibration modes and I think the thin layer element 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.
Best regards,
Hao
If you use the Structural Mechanics module, you can find the Thin Elastic Layer and many other option to be used in your 3D simulation.
Regards
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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
1. 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.
2. 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?
Hi all
The examples I provide do increase stiffness. The first example from internal maths, the second example from autoconstraining connecting dependent RBE2 dofs to ground and the last, connecting rotational dofs to ground.
If you look at hour glass modes where element formulation provides internal resonances, there I'd say that you lose stiffness .
Connecting beams to membranes, you will likely deal with all of the above.
To elaborate on the RBE2 - a rigid beam element - using it to connect a beam (6dof) to a solid (3dofs) - you get problems with the 3 rotational dofs. If the dependent dofs are on the solid, these get constrained to ground.
The practical workaround is to add a thin shell onto the solid element and to define it using a material with zero density to avoid spurious resonances in the thin shell.
Just my 2 cents
C
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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
Nesrine El Houari Thank you but already check the manual and did not mention it
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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.
In APDL main menu, you should use Select Enitities, It s a usefull tools for selecting and unselecting everything such as node, kepoints, element and etc.
First use Select>>Entities
then use "Element", "By Num/Pick" , after that select the element you want.
After that you should use again Select>>Entities, then used "Node", "Attached to"
after that select the element. then use Plot>>Nodes.
I made an example and put it in the attached photo, I hope it is useful.
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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 asymmetry 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).
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
yes, your diagnosis seems correct since the difference is of order of 1e-8. in computers, no floating point number can be represented exactly. therefore, it's common to use some epsilon value is used to avoid it. alternatively, when writing from scratch, only upper or lower diagonal is saved in the memory for a symmetric array to avoid such issues.
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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 ).
Embedded beam element or shell element
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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 .
if you have a time-dept simulation, you can create a multiplyiting function with LIST_REEL and DEFI_FONC.
Franco
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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?
If you plot stress/strain of an element (if that is what you are doing), you will always recover the curve you entered for your material behaviour. Doing this will not serve as any kind of verification of your model.
If you want to compare to experiment, you need to do the same thing as in the experiment: Calculate the distance between two points and the total force on the part, that will give you a true force-displacement curve which you can compare directly to your experiment.
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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.
Reduce the printing speed; examine the Z-axis level; the machine may need a complete calibration; and inspect the mechanical components that hold the extruder.
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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.
Left-click the mouse at the bottom edge of the screen to see the symbol of splitting and drag it upward.
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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!
Interesting question. Following.
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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
0.002, 1, 1e-10, 0.002
*Solution Technique, type=SEPARATED
*Controls, reset
*Controls, parameters=time incrementation
5000, 5000, 5000, 5000, 5000, 5000, , , , ,
--------------------------------------------------------------
Mojtaba Ab
#Abaqus #fem #FE_Analysis #FEM_Simulation #Plasticity #Fracture #Elastic #Simulation
Abaqus has two different option in order to make you simulation faster.
1- use multiple processors which you currently use
2- use GPGPU acceleration , which uses the GPU (For example CUDA Core in Nvidia Graphic)
I suggest you if its possible and If you have PC with high GPU core , run your model with GPU.
In Abaqus Job Manager this option is available.
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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.
ABAQUS/ LS-DYNA are very good for blast impact analysis.
Best regards,
S M
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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.
Excel is not a file format. The spreadsheet can simply be saved/exported as csv or tsv which can be used as any other normal file in any script.
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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.
Mesh size is not a parameter in my study.
Regards
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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).
I would be grateful if you guided me through this.
Reza Pourshab Could you please share how did you implement time variation of load? I am struggling with that...
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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 ! :)
Hi,
You may get some useful information from the following paper:
Solution of a coupled inverse heat conduction–radiation problem for the study of radiation effects on the transient hot wire measurements
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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 !
I see, I did find the imput for the Volumetric loss density, electromagnetic (ec)
But, when I fix the Heat Source with this source, I got no Temperature (see attached image please)
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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.
(my model is attached below)
Hi,not yet, can you help me?
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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.
". . . The thermal optimization is not documented and not supported directly in Abaqus\CAE. Thus, you have directly to edit the parameter file for Tosca for adding the thermal optimization commands and then execute Tosca directly using an additional license. . . . "
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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.
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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.
Maybe this topic will be of some help:
Best regards
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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
Thanks.
Dear.
I suppose you worked on Ansys.
Zero length problem happened when you wrongly click on the same node twice (in link element).
Go to select entities > elements > by attributes > check the element number > delete it.
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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 the advice Michele Raucci.
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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.
Here is the summary of the methods that can be used to implement a control system in Abaqus. I will provide a detailed discussion of these approaches in a separate pdf file.
Abaqus uses UAMP subroutine as a built-in solution to model control engineering aspects of the system.
At the beginning of each 'increment', Abaqus provides UAMP subroutine with 'sensor' data (defined in .inp file). Upon receiving this new data, UAMP applies the control law (through one the methods discussed in the following) and returns updated 'amplitude' to abaqus analysis.
1. If the control function can be implemented in FORTRAN, no third-party software is required for your control application.
2. In this method matlab controller function is exported as an executable file (.exe) which is called by FORTRAN 'system' function along with its input arguments in UAMP subroutine. Controller is designed to write its output in a file which is shared by Abaqus and MATLAB. Abaqus reads the file, updates 'amplitude' and resumes the analysis. (Note that MATLAB standalone executable files are slow. This issue is also discussed in MATLAB forums)
3. In this method a local server is established which acts as an interface between MATLAB and FORTRAN code. using cURL command in UAMP subroutine, a POST request is sent to localhost where MATLAB is constantly listening to for new incoming requests. Upon receiving this new request, MATLAB runs controller function and writes its results in a files shared by Abaqus and MATLAB. Abaqus reads the file, updates 'amplitude' and resumes the analysis.
Third method is a reasonably effective method for MATALB/Abaqus co-simulation.
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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
📷hi Qusai, could you please walk me through , how you have implemented the stress eq. 1 in your model.
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