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Hello fellow academics,
For my Final Year Project, I am looking into different ways of modelling the interface between PVA and gelatin. I have successfully modeled the interface using the "tied" constraint, however now I am looking into using the "embedded region" constrain to model it.
As you can see the the attached screenshot of my model, I have attempted to overlap the two blocks and assign the embedded region feature, however when I try to run the job it gets aborted.
I have attached the input file to this post so if any of you are knowledgeable with Abaqus CAE and constrains could you help me find out why the job is failing and how I can fix it.
Thank you for taking the time to help me,
Remi
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As far as I know, embedded region is a kind of constrain and does not require any surface-to-surface interaction definition. But in my opinion the use of contact interaction instead of embedded region is more reasonable in your model.
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I am performing the earthquake analysis on bridge structure in ABAQUS CAE under Dynamic Implicit step. I am getting the error as shown in the picture attached.
Please see the attached picture of error.
All elements are C3D8R.
How to resolve this error?
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Hi everybody,
Nice question Muhammad Farhan, I am slightly familiar to ABAQUS, but after many tests, in analysis of systems with nonlinear behavior of piece-wise linear type, even when the iterations of nonlinear solution do not converge you may continue the analysis and arrive at sufficiently accurate responses. (This may be also true for other types of nonlinear behaviors.) The reason in brief is the fact that the computed responses are at least under the effects of two independent sources of error; one because of nonlinearity, and the other due to approximate time integration, also see:
(a) Soroushian, A. and Wriggers, P., 2023. Test of an Idea for Improving the Efficiency of Nonlinear Time History Analyses When Implemented in Seismic Analysis According to NZS 1170.5: 2004. In International Conference on Wave Mechanics and Vibrations (pp. 107-114). Springer, Cham.
(b) Soroushian, A., Wriggers, P. and Farjoodi, J., 2015, May. From the notions of nonlinearity tolerances towards a deficiency in commercial Transient Analysis softwares and its solution. In Proceedings of 5th ECCOMAS thematic conference on computational methods in structural dynamics and earthquake engineering (COMPDYN 2015), Corfu, Greece.
(for he first the movie of the presentation is also available in my researchgate, I may not be able to attach now)
OK, with many thanks for your kind attention, have a nice day tomorrow and all future.
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Hi everyone, So i have an orphan mesh of a composite material, i want to duplicate it couple of time side by side so it would work together. I have tried the option "copy mesh patterns" but couldn't do it because it says it has no boundaries! Any suggestion how to solve this issue?
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You can try the tips given in this thread:
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Hi, All. I believe some of you also meet this problem. After submitting a job, you have to monitor the status from time to time to check whether it is finished or not. Can be set a "beep" reminder after the job is finished. if so, you can do something else without checking whether it is finished or not from time to time but only return to process the calculation results when the reminder sound appears.
Thank you all for sharing your suggestion.
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I remember the concept of using "hwinfo" or similar monitoring tools to detect the usage/change of certain hardware, e.g. cpu, and defining respective notification cases. Hope that helps.
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Hello,
I'm making few python macros for Abaqus, to be able to manage rapidly many models, and many output databases.
For one of those, I need to be able to automatically retrieve the names of all the History Output Variables (as:” Artifical strain energy: ALLAE for Whole Model”) using python, and I can’t find any other way to do it than using the .inp.
Does anyone know how to do this? I tried to use .keys() on historyRegions[].historyOutput[] but I don’t get the same names or data than those I have in abaqus CAE.
Thanks
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Hi Benoît,
I hope that you have already solved your issue.
In any case, here a possible solution; other people may have the same issue:
# Open the odb
odb = session.openOdb(odb_dir + ODB_name+".odb")
# Access the step
my_step = odb.steps[stepname]
# Access to the history regions containing the set with all the elements
my_hist_el = my_step.historyRegions['ElementSet ALL ELEMENTS']
# Access the history output and look for the KI
my_hist_el.historyOutputs.keys()
This commands should give you access to the keys of all the history output present for a given step.
I hope it helps.
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Hi everyone,
I ran a model in my ABAQUS CAE, however, when the simulation finished, the elastic modulus of the model appear to be higher that the elastic modulus of the material that I had assigned. Is this possible and what factors that affect the model to behave in such ways? Thank you in advance.
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The question sounds misleading and seems to confuse the concept of "elastic modulus" (which is a material property) and "stiffness" (which characterises a structure under certain BCs). It is indeed not possible that the elastic modulus changes in an analysis, as it simply defines the Hook matrix used in computation of element stiffness matrices
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I have submitted a job in ABAQUS 2020 with a model of padeye being pulled in one side. The status in abaqus is:
The job "SpreaderV1" has been created.
The job input file "SpreaderV1.inp" has been submitted for analysis.
Job SpreaderV1: Analysis Input File Processor completed successfully.
But after almost an hour the solving process is not started yet.
I am using ABAQUS 2020, because in ABAQUS 6.14 I got error code 1073741795. It might have something to do with my processor.
My PC specification is:
AMD Ryzen 5 5600H (6 Core, 12 threads, 3.5 GHz)
RAM 16 Gb 3200.
Or maybe Abaqus is not optimized to run with AMD processor? I think the processor computing ability is not the problem since overall Ryzen 5 5600H is better than many gen 11th intel processor
I can run simple job like simple box with surface load, truss analysis, etc just fine (with 6.14 and with 2020 ver). Maybe ABAQUS (both for 6.14 and 2020 needs some tweak to run fine with AMD). I have uninstalled the 6.14 ver
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There is an exclamation mark by the tab "Warnings". Can you look under that tab to see what it says?
Simon
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Dear all,
I have tried to simulate the phase change from a solid to liquid in Ansys FLUENT by providing heat flux at a wall [Using the Solidification and Melting model]. I got the results [video attached: 0-1 min temp plot, after 1 min liquid phase plot]; the heat flux creates temperature change over time, leading to a change in phase based on the solidus and liquidus temperatures.
But, the fluid flow doesn't occur, i.e., the flow equation is not solved. I want to simulate the flow of liquid PCM due to gravity. Is there any predefined option to perform that? or is any udf available? Kindly help me..
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Prince Abraham Turn on gravity option on, and use techplot soft for particle movement. that will give better result . or you can also go for rockey 2.0 software.
Find below article in which you can see flow,:
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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
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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 am trying to mimic the motion of a knee joint and need the femoral component to slide along the surface of the tibial component. I have tried using reference points and a coupling constraint but nothing is working for me. how do you think I should tackle this issue. Furthermore, the rotation and translation are time dependent and also there is an axial force that is placed on the joint that is time dependant. Please help.
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Ramanan Lakshminarayanan for this simulation I chose the find contact pairs and defined the surfaces in contact accordingly.
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I have been trying to model a dent-crack defect on a pipe surface. Therefor, the pipe, the crack and an indenter has been designed. The indenter is supposed to go down the pipe surface 63.53mm...now the model runs quite well when the displacement is around 40mm...but it gets abborted when I try with 63.53mm...
Does anybody has any solution to that?
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Hakim Dina Anjum thanks for your contribution, looks like playing with the tolerance actually helps. But, there seems to be a new problem which shows increased von Mises values than the actual ones. By the way, I'm using Abaqus for modelling.
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Hello,
I am doing an additive manufacturing simulation in ABAQUS/CAE 2017.
I have two working subroutines: DFLUX and UEPACTIVATIONVOL which both do their jobs correctly in separate models. I need to combine them but for my moving surface flux, the surface I define in the model does not work due to the activating elements during the analysis form the UEPACTIVATIONVOL. (The surface I define in the GUI for the heat flux does not exist at t = 0 since the elements are inactive)
Is there a way to define the top element face as a surface and change that in a subroutine for my DFLUX subroutine to call so the heat source will be applied on the surface of elements on one layer and then apply to the elements top face on the next layer?
Thanks in advance for your help!
Shaun
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Manik Patil You as well. Best of luck!
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I am trying to model excavation procedure of tunnel (D-shaped) in Abaqus (CAE). I have obtained the RF1 and RF2 from an independent analysis as given in Abaqus example (Abaqus example problem guide/1.1.11 Stress-free element reactivation). Now, my problem is that how to apply those concentrated forces ((2n+1)*2) on corresponding nodes?... Because, in my model total number of nodes (2n+1) on tunnel periphery are 129 (in the abaqus example, there are only 13 nodes). And, its changing with each trial/variation of mesh size.
So, how should I apply the concentrated forces?
i) one by one clicking each node, creating each node a set and then applied the loads from load module ? (it's tedious/repetitive. I don't want to do it) or
ii) Doing some editing in *.inp file? (But, when I tried with following format, ABAQUS is simply neglecting my edited lines:
*CLOAD
node number, direction, magnitude) or
iii) writing ULOAD subroutine?
Please clear my doubts.
Thanks in advance.
Regards,
Dipaloke
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So your input file looks like something like this ? (CLOAD statements for each node ?) :
*CLOAD
node number, direction, magnitude
*CLOAD
node number, direction, magnitude) or
*CLOAD
node number, direction, magnitude) or
...
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Hi everyone,
Is there a method to divide the imported part into multiple parts within Abaqus CAE?
I am working on a model in Abaqus CAE with a geometry imported from a .STEP file. I need to define non-design regions by defining parts which are separate from the design region. For example, the design region must be named Part-1, while the remaining of the geometry is divided into Part-2, Part-3, etc. However, the whole geometry is imported as a single part from the .STEP file even though I check the "create individual parts" option during the import process.
Please note that, since I need the non-design regions to be in different parts, I cannot use the partitioning methods (e.g. cell partitioning).
I will be grateful for your comments and insights.
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Have you found a solution to this that you tried and works?. I am in similar boat with slight variation, I would like to just partition and assign a different material to my step file. However abaqus is not allowing me to partition.
Kind Regards,
AM
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Good day, I'm trying to model a composite curved specimen on Abaqus, but I have problem in understanding how to define a reference system that represents the orientation of the fibers all along the curvature. As far as I understood, this can not be done in the CAE but only in the text editor, however by reading the manual, I'm not sure on what I should write.
If any of you had any kind of example, alternative and insight on how to do it, I'd appreciate it very much.
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Please check the attached template Abaqus input file.
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I am using Abaqus UMAT subroutine to model wear damage between two contacting steel surfaces. I need to get the absolute maximum shear stress as it is a function of my wear damage model. I have tried using a utility routine called CALL SPRINC to get the 3 principal stresses ( σ 1,2,3). Since abs max shear stress = (σ1- σ 2)/2, ( σ 1- σ 3)/2, (σ 2- σ 3)/2 (the numerically largest of these).
However, it gives me principal stresses for each number of element and increment (which are thousands or maybe more than that), and I do not know how to assign the values to different variables in order to calculate the abs max shear stress using the eq. above. How do I assign the values in different variables?
I have also tried using the trigonometry (with the calculation of discriminant) to solve the cubic formulation to get the principal stresses manually but there is an error in trying to run the program as follow: The executable standard.exe aborted with system error code 1073741676.
1. Is there any way to directly get the abs max shear stress in UMAT subroutine?
2. How do I assign principal stress values in different variables?
Thank you!
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I am analyzing the squeal of Disc Brake Assembly using Abaqus and I tried to find the unstable frequencies using complex frequency which caused the squealing noise: I am able to find the unstable modes but they are not forming a stable unstable pair. Also, the participation factor is coming for many modes. I am attaching the brake model for reference. Please help me to find unstable frequencies using Abaqus?
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Hi
For complex modal analysis, I fear we are all beginners.
Positive damping is conversion of vibration energy into heat, a nearly irreversible phenomenon, ie a power loss.
Negative damping implies power input, ie excitation.
Whether a mode get negative or positive damping depends on several factors. The cross product between transportation (rotation) and vibration matters, as does the mode inherent damping. Add to this effects from a spinning body where you get forward and backward rotating modes.
A well studied phenomenon that contain the same base physics is wind excitation of a circular elastically suspended body.
Anders advice wrt Jim Woodhouse is very good advice. In my mind, his work is sterling quality.
Hope this helps
Claes
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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.
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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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Performing the bolted joint simulation in abaqus CAE using contact pair algorithm
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You have to consider shank circumference while applying bolt load and apply pretension.
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Hello dear colleagues,
I want to reproduce the surface topography of metal additive manufacturing samples in CAD and CAE environments. What is the best way to capture surface topography and how can I reproduce it?
Any recommendation is appreciated in advance.
Best regards,
Hamidreza
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Hi, If you want to capture all the surface features (pores, cavities) generated during the LPBF process, especially Rv surface roughness with high resolution, use a laser scanning confocal microscope.
See our paper:
"Enhancement of electrical conductivity and corrosion resistance by silver shell‑copper core coating of additively manufactured AlSi10Mg alloy"
  • Surface and Coatings Technology 403(C):126426
  • DOI:10.1016/j.surfcoat.2020.126426
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I am using Abaqus/CAE for Laser Shock Processing (LSP), Can I import the simulated model file to Ansys Workbench for further analysis as I have to run two simulation for fatigue, FOD damage analysis? Firstly I need to execute the LSP simulation on ABAQUS and then use the same model for further fatigue Test.
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hi
use external model and then connect it(drag and drop) to other modules that are needed
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Hi,
I'm trying to create several displacement data tables through iteration (see 2.PNG) but get an error for the second iteration (see script "Test of small codes.py"). However, the values for the first one are correct.
The main problem is the "#Displacement XY data" part (see 1.PNG), which does not create the second iteration.
Is there any method to solve the problem and be able to avoid getting error messages?
Any help is appreciated,
P.s. If you want to run the script, run "I-Profile_iteration_Test.py" first, and when it's done, run the second .py file.
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I believe you should be able to use a COM (component object model) library, as in this example for the specific case of interacting with iTunes:
# iTunes API
import win32com.client
import pandas as pd
import Cria_PL
import Proper
# CHECA PLAYLISTS
iTunesApp = win32com.client.Dispatch("iTunes.Application.1")
Sources = iTunesApp.Sources
# PLAYLISTS
for i in range(1,Sources.Count+1):
source = Sources.Item(i)
if source.Kind == 1:
playlists = source.Playlists
print("Select from the following playlists")
print("Number of playlists:",playlists.Count)
for j in range(1,playlists.Count+1):
playlist = playlists.Item(j)
playlistName = playlist.Name
print(j, ":",playlistName)
# LIST TO BE PROCESSED
result = input("Enter comma-separated lists to process: ")
print()
#result = 12
# SELECTED PL
read_PL = playlists.Item(result)
playlistName = read_PL.Name
print("Processing playlist",result,":",playlistName)
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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.
Please help.
Thanks in advance.
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I need someone to run a job on Abaqus for me, the model is correct, I ran it with 4000,8000 and 10000 elements, and the one with 16000 takes more than three hours and it ends with the error message "Process terminated by external request (SIGTERM or SIGINT received)"... i uploaded the cae and jnl files.
if you manage to get the complete odb file please send it to me here : bachirsara.1994@gmail.com
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No matter termination reason, you should check the results. Cracked systems, unlimited defs, or any other ends of analysis may couse the sign term... Irrelevantly, check your computer for network connection stability, power saving settings etc., check *.dat or *. log file...
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I am using Abaqus CAE software for hot compression of cylindrical specimen. For making cylinder i am using axisymmetric model and make rectangle but i want to make rectangle in XZ plane ie height along z axis but in Abaqus by default it on XY plane. So i want to know how to change viewport plane axis from XY to XZ plane? Please answer it
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You can try to rotate 90 degrees around the X axis in the Assembly module after establishing the model in the Parts module, which can also get the effect you want.
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Hello Everyone,
I have a comprehension question regarding the material orientation in ABAQUS. Specifically, I have a VUMAT for anisotropic material behaviour and would like to use that in a cylindrical 3D-model. I understand, in ABAQUS the cylindrical orientation is defined by x=radial, y=tangential and z=axial. Furthermore, I think sigma_11=x, sigma_22=y and sigma_33=z. However, I have determined the model parameters for x=0°, y=90° and z=thickness. So I need a coordinate system defined by x=axial, y=tangential and z=radial. Could someone please help me out on how to proceed? Of course, I can reverse the stress definition in the VUMAT, but that cannot be the solution. So where is my thinking error?
Many thanks in advance and kind regards
Stefan
PS: I am not using CAE since I use a small python script to create the inputfile depending on some variables.
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Hi Yunpei,
thank you very much. I am not so fit in CAE, but I think that creating a "datum coordinate system" with CAE results in an *ORIENTATION card in the input file. However, in a cylindrical system, X is given as the tangential direction and Z as the axial direction. There is obviously no way to change this.
Kind regards
Stefan
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Dear all,
I am writing an Arc-Length (Riks) code.
The arc length formulation is as follows: (Screenshot 2021-08-26 171826.jpg)
Where q is the load vector.
My question is how we can use displacement vector instead of the load vector (q) in arc-length method. I know it can be defined in CAE Abaqus, But there is no information in its manual.
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simple answer can be MATLAB.
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I've been running a simulation in ABAQUS that takes up to a week to run. However, occasionally the simulation stops running (the computer's CPU usage is at 0%), while in ABAQUS CAE, it says that the job is still running. Does anyone know what the cause for this error might be?
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Agree with Arjun Kalkur Matpadi Raghavendra
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Dear All,
I just Installed Abaqus in my computer and Abaqus CAE 6.14 works fine. But, every time I submit a Job it runs for 2 seconds and then I get the following message:
The executable standard.exe aborted with system error code 1073741795. Please check the .dat, .msg, and .sta files for error messages if the files exist. If there are no error messages and you cannot resolve the problem, please run the command "abaqus job=support information=support" to report and save your system information. Use the same command to run Abaqus that you used when the problem occurred. Please contact your local Abaqus support office and send them the input file, the file support.log which you just created, the executable name, and the error code.
I looked for information already and It seems to be something related to memory allocation but I am not sure...
does anyone have ever get this error before? do you know anything about it? is there any solution??
Please I need your support.
my computer is a NEW Lenovo Laptop - AMD Ryzen 5 4600H with Radeon Graphics 3.00 GHz - 16GB Memory - 500GB SSD with windows 10.
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AMD R5 CPU does not support avx2 and mkl which are developed by intel in abaqus6.14.
firstly,RENAME the mkl_avx2.dll TO mkl_avx2.14.0.0.1.dll or mkl_avx2.14.0.0.1.dll.
if it does not work, use abaqus 2018 or later
if you must use 6.14, use the step-other-method-iterative instead of step-other-method-direct .
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Hi there!
I have been using Abaqus CAE to model a CT-specimen being pulled apart, in order to observe the resultant plastic zone shape around the crack tip. To reduce computational cost, I have modelled a quarter-specimen with the appropiate boundary conditions, and hence am able to easily see the development of this plastic zone from the mid-plane to the surface.
Upon setting certain threshold values when visualising the end result (yield stress and PEEQ values), I am able to see what the area is that has deformed plastically. I have attached an image to show what this looks like in Abaqus.
I was hoping to find out how I may be able to calculate and quantify the area of this region defined by threshold values along each 'slice' of mesh in the X-Y plane. I have separately meshed the plastic zone area with 30 layers - which indicates that I should be able to extract 31 different area values (as Abaqus calculates the simulation at nodal points and coordinates). Any help would be appreciated.
To describe the images attached: In the first image, the area in grey shows the plastic zone - the area where stress values are above the yield stress of 425MPa. The second image shows a contour drawing of the edge of this plastic zone through the specimen - I aim to calculate the sectional area along this length at each mesh layer interval.
Thank you in advance! If anything is unclear, please let me know.
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I think you can create display group (method – Result value, Boolean operation - Replace) to visualize only needed elements, then use Quiery…/ Mass properties. At the bottom of the screen you will read Volume. Then Area=Volume/Thickness.
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Hi,
I would like to apply a defined value of initial stress on 3D Shell elements in the initial step in Abaqus CAE. These shell elements are connected to a 3D Deformable Solid by a Tie Constrain. I have also tried to connect them through "shell-to-solid-coupling" constrain, but the same result. After the initial step, I provided a self-equilibrium step without any loading (Figure 4).
My problem is that after the next steps when loading starts a fast relaxation of this shell element (Figure 1) occurs without transferring the stresses to the tied 3D Solid shape (Figure 2). The tie properties are as shown in Figure 3.
My question is how to transfer a prestressing load (predefined field: stress) from a shell element to a 3D Solid, tied to each other since the main reason for this prestressing is to provide a negative deflection in the main structure?
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if you want to include the initial stress in your model, you need to edit the subroutine code by attaching the initial stress value to selected shell elements.
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I'm going to analysis of theorical RC beam by FE nonlinear analysis then verify the RC beam models with FEA softwares.
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I think this article will help you
Genikomsou, Aikaterini S. and Polak, Maria Anna (2015) Finite element analysis of punching shear of concrete slabs using damaged plasticity model in ABAQUS, Engineering Structures, Vol. 98
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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).
How to model these two components of the load by VDLOAD?
I would be grateful if you guided me through this.
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Reza Pourshab Could you please share how did you implement time variation of load? I am struggling with that...
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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 spatial distribution works fine. For variation with time I made an amplitude in CAE module but it is not behaving as desired.
As in VDLOAD subroutine there is an amplitude variable which is un-modifiable.
i want to ask what is the use/function of that variable?
should i need to write codes for the variation with respect to time of Pmax or it will be done automatically ?
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Abhishek Abhishek Did you find solution to your problem? I am having similar problem.
Meysam Khodaei I want to a load linearly increasing with time so I created amplitude Amp-1.
*Amplitude, name=Amp-1
0., 0., 1., 1.
As you mentioned, I added amplitude to the line where we define load.
*Dsload, amplitude=Amp-1
_PickedSurf86, PNU, 1.
Still, I got instantenous loading which is causing vibration in model and I could see it from energy plot? Any suggestions how to avoid this?
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Greetings.
I am analysing a steel beam under flexure in ABAQUS CAE. I have modelled the beam (made from 1.2mm thin plate) using shell elements. I need to provide a thicker web stiffener ( 6mm thick) so, it has been modelled using solid elements. I am providing a surface to surface Master-Slave interaction. For some reasons unknown to me, warning messages appear regarding Numerical Singularity and after some repetitive messages, the analysis aborts. What is the possible reason for this type of error? How do I rectify it?
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Can you share your Abaqus model (.inp)?
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Dear all, I am using XFEM to simulate crack initiation and propagation process, but according to the ABAQUS document, some features are not supported by ABAQUS CAE, such as
*SURFACE, TYPE=XFEM
Checking the *SURFACE keyword in the document, I couldn't find where to put this keyword in the inp file. Should I put it above *ASSEMBLY? or another position?
Could someone tell me where to find the instruction about keywords positioning?
Much thanks.
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Yes, keyword position does metter. In the case of incorrect position, Abaqus gives an error message with explanation of reason.
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Hello!!
I am new to the ABAQUS/CAE, and working on ballistic simulation on Fabric. Any insight on how to use VFABRIC subroutine in ABAQUS would be appreciated.
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Thank You for your response, these are really valuable inputs for my project.
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Hello,
I am a new user of ABAQUS/CAE and is working on ballistic impact simulation on fabric. I referred many research article for the same, but doesn't got the clear image about its simulation.
It would be very beneficiary for me if anyone can let me now how to do material modelling of a fabric or refer some good article.
Thank You
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Hello sir,
Thank You for your response, these are really good inputs.
I have another question: How will the inter woven characteristics (like the weave pattern, crimp) of the fabric taken into account?
Should I model the fabric in pre-processing software like TexGen or WiseTex and then have to write a user-subroutine for the same?
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Hello all!
Any insights or suggestions on resolving the following issue will be appreciated. Thanks!
---
The objective is to apply equal and opposite concentrated force on the two faces of an embedded crack in an ABAQUS CAE model.
Thus, and ABAQUS model with an embedded crack was created using the crack seam feature in ABAQUS, {defined with q vector, Collapsed Element side single node}.
How can one access the overlapping nodes along the crack seam independently to apply equal and opposite loads ?
Is there a way to create a Node set using just the Node Label without selecting it in the viewport?
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The main problem is nodes overlapping. I usually create an element set containing all elements adjusting to one side of seam. Then I create display group from this set using Replace as Boolean operation. This way I can work with nodes on the one side of seam. If Invert Display tool on the Display Group panel is turned on, all nodes on the second side of the seam become available.
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Hi everyone.
I am looking for a guide (paper or book) that exhaustively explains how to model viscoelasticity in ABAQUS CAE.
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Hello,
Maybe you can use this work.
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Dear all,
I want to model a 3D rubber in Abaqus (dynamic explicit). When I run the model, the analysis is aborted before it starts and this error appears: “Analysis Input File Processor exited with an error”.
The Marlow model (in hyperelastic properties) is used in this modeling. It should be noted that when using other models (for example ogden model or polynomial model and etc.), this error does not appear and the analysis will be complete.
Can you please suggest a solution?
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check with the warning label, it would give you some hint. Moreover, try to use some default parameters or others' set in Marlow model. Change one parameter each time. You would find the problem.
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I am trying to import a material library (.lib) in Abaqus/CAE 2017 but i don´t know how can i do it (I only know how to create a material library).
Would anyone know how to do it?
Thanks in advance
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You need a plugin for that check in abaqus plug in menu, if it is already available other wise download and install it.
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Are tire damping co-efficient and stiffness material-dependent properties or related to tire pressure?
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Both the parameters are considered. However, many more parameters are taken into account while varying the stiffness and damping coefficient.
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I want to plot a force-displacement curve for a static RIKS Nonlinear analysis model, so I need to get the point that has the highest displacement to do this.
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To locate the node with max displacement toggle on Show location in the Max area (Visualization module: Options->Contour: Limits tab).
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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.
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I received an official answer from SIMULIA as follows:
". . . 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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When I try to start a simulation in ABAQUS CAE with *.inp and *.f(umat file). The abaqus just prompt an error:"Unable to start analysis job" and stop without any debug message. The example files in the Abaqus Document do not work either. I tried every method on the Internet but all failed. Do someone know how to deal with this problem? Thanks a lot!
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I'm currently trying to run a ballistic impact simulation on Kevlar composite plates on ABAQUS CAE through the dynamic explicit simulation. However, each time I try to run my simulations, this error will appear and I am left with aborted simulations. Additionally, the properties of my Kevlar material may be inaccurate especially with the Hashin Damage properties.
Can anyone assist with this issue?
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This can occur due to the high load rate or size of components that are defined as deformable. This error generally occurs in analyzes in which the material undergoes many deformations.
To fix this error, preparations must be taken so that the elements do not deform too much during the "job" solution. Using the following tips can help:
1-Minimizing the size of the elements and changing the meshing techniques of the structure in such a way as to increase the quality of the created elements can help to completely solve the analysis.
2-Changing the order of the elements from 1 to 2, although it significantly increases the amount of analysis and space occupied by the computer's RAM, it is one of the easiest ways to increase the probability of completing the analysis.
3-In some cases, it is possible that the level of calculated strains may be so high that the material enters the area of its damage, and to continue the analysis from a certain point onwards, the damage criterion for the material must Have been defined. Failure to define the appropriate onset and growth criterion of damage is one of the common mistakes of Abacus users that can cause this error.
4-In cases such as some shaping analysis in which increasing the mesh density and increasing the order of the elements alone do not complete the analysis, the Arbitrary Lagrangian-Eulerian adaptive meshing algorithm can be properly defined for "parts" with high deformation. To a large extent, led to the completion and advancement of the analysis. using this technique in simulation, like other solutions, increases the analysis time.
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I am doing a project in which I need to do an impact analysis using Cricket ball in ABAQUS CAE. I've used Density:811.11kg/m3 and used Hyperelastic (Mooney-Rivlin Coefficients) from a research paper as C10=3.09068828, C01=-1.49503368, D1=0. When I used only these properties I got error that one part of ball is expanding a lot. Can you please suggest me the material properties that I need to use.
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Ok dear after some time I will give this answer .
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I am working on simulating Welding using the Goldak Double ellipsoid heat source model in ABAQUS. But I am not sure how to define the heat source as mentioned in the equation and also defining the initial coordinate system and step time.
It would be great if anyone can help me with this, by providing an appropriate case and CAE file...
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In Abaqus, you have the option called user subroutine to define the heat flux
For defining the Goldak subroutine you can use Dflux.
The double ellipsoidal equation can be mentioned in H(1).
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Dear all,
I am trying to use a Unix cluster for my simulations and I have to run the Abaqus using the terminal. I have the python script of my simulations but when I try to run it using "abaqus python 'scriptname'.py" I get this error:
Traceback (most recent call last):
File "b.py", line 2, in <module>
from part import *
File "SMAPython/SMAPytLibPy.m/src/site.py", line 120, in _numpyHook
"""Append ./build/lib.<platform> in case we're running in the build dir
ImportError: No module named p
I am aware that I am running the script from the command line, so it has no access to CAE related module, methods or objects, but what the solution can be for this specific problem?
Thank you in advance
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Hi Mehrdad,
I think you should try:
If you use the command "abaqus python scriptname.py" it just calls the python kernel of abaqus in which you have not access to Abaqus modules. So you got this error. If you use "abaqus cae noGUI=scriptname.py", on the other hand, you call the whole package. So at the beginning of your code, you can import different modules like:
from part import *
from material import *
.....
---------------------------------------------------------------------------
Extra steps for your shell/abaqus/python project:
If you like to run this using a python script, you can use subprocess library and write:
from subprocess import check_output
check_output("abaqus cae noGUI=odb_reader.py", shell=True)
If you wanted to run abaqus for job.inp, you can use this:
abaqus job=simulation.inp double cpus=4 interactive
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Hi,
I was practicing Isight optimisation tool with Abacus.
Features used
1. optimization genetic algorithm
2. calculator component
3. NSGA-II - Nondominated Sorting Genetic Algorithm
I had imported the CAE file of ansys and followed the procedure available in the internet.
But I get a error which I do not understand. But I am sure that the error do not say and missing parameter in the input.
After I run the file, I get following Error for one step. And 7 such step is executed, which all contain same error message.
The message is
1. Component "Optimiyation1.Abaqus" failed execution
1.1 There was an error preparing the run. Please see abaqus_rpy output file parameter(abaqus_rpy output file parameter) for more information.
1.1.1 com.engineous.sdk.runtime.RtException: There was an error preparing the run, Please see abaqus.rpy (abaqus_rpy output file parameter) for more information.
1.1.2 at com.engineous.component.abaqus.AbaqusExecutor.execCae (AbaqusExecutor.java:1668)
1.1.3 at com.engineous.component.abaqus.AbaqusExecutor.execCae (AbaqusExecutor.java:205)
If any one has faced any such issue, please share your experience.
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Hi every body
I need to export composite material unit cell from Abaqs to Isight (Motne carlo) , however the the imported output file (ODB) show only von Misses stress , and I need the output to be composite properties (E1 , E2 , E3 ---- so on), how can I solve this problem? , how I make ODB file includes material properties to be read by Isight.
thanks you
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After analysis of a model in ABAQUS CAE, in the results of Pore water pressure am getting white color (in spectrum) as shown in the attached picture. What does it mean..?
Hope someone will help me in this. Thanks in advance..
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Victor J. Аdlucky thanks for replying
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Hello,
I am writing a python script to generate my model and write the input file. The problem is I have 1000 elements in my mesh and I want to assign different material properties to each element. I was able to create the 1000 material constants and was able to create 1000 solid section. However, I don't know how to link a solid section to an element in the mesh. Usually in Abaqus CAE using the graphical interface the material is created well before creating the mesh.
Below are my code for creating the material and sections and link them together.
Should I create the mesh first then try to assign sections to elements by label?
I also tried to record my steps in macro but the problem is if I go to property the mesh disappear and I cannot assign sections to elements there
Below are my code for creating the material and sections and link them together.
for el in range (1,ele+1):
mdb.models['Model-%d' %(q)].Material(name='M%d' %(el))
mdb.models['Model-%d' %(q)].materials['M%d' %(el)].UserMaterial(mechanicalConstants=M[i])
mdb.models['Model-%d' %(q)].materials['M%d' %(el)].Depvar(n=700)
mdb.models['Model-%d' %(q)].HomogeneousSolidSection(material='M%d' %(el), name= 'Section-%d' %(el), thickness=None)
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Dear Ahmed Aburakhia,
I think you should mesh your part (not part instance) and create element set for each element. (Part module>Tools>Set>Create…: Type – Element). Then record macro while assigning section to element set (Part module>Assign>Section: select Sets… (on the right hand jn Viewport)).
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Hi, all! How can we use a hybrid element in Abaqus Dynamic/Explicit for impressible materials? I have not find the choice for explicit element in Abaqus CAE. I am wondering whether it is possible used a hybrid element in Abaqus Dynamic/Explicit by changing the keyword in an inp file?
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Dear George,
Thank you very much for your anser. Do you have any ideas how to solve the hour-glass problems caused by incompressbility in Abaqus Explicit?
Best Regards,
Changhong LINGHU.
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Hello,
I am working on a paper and looking for an existing Validated Health Care Survey/Instrument. I have been performing virtual ergonomic evaluations since the start of COVID and want to capture the perceptions, attitudes and outcomes of the assessments. I think it is important to learn from this change in service due to COVID and understand the strengths and weaknesses of the assessments.
Thank you,
Dr. Kathryn Meeks PT DPT CAE
Optimizing Motion
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Thank you very much!!
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I am trying to import an Abaqus .inp file to Ansys but it does not import the whole assembly but only imports a single part. How to solve this.
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You can generate flat file format through Abaqus CAE too, by clicking the "Do not use parts and assemblies in input files" checkbox in the "Edit Model Attributes" dialog box (Model->Edit>Attributes).
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I want to simulate a rough surface in Abaqus CAE by transferring nodes in the input file but I have problem in large number of nodes transferring. so I have following steps to pre-process:
first step is simulating surface roughness in MATLAB program by writing codes.
step two is sample model generating in Abaqus CAE.
step three is meshing the sample to the requirement value.
step four is how can I write MATLAB codes to transfer top surface nodes in large numbers nodes? Actually I want to write MATLAB codes to find top surface nodes of sample and then change them to requirement value.
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Or this one:
Or if you want to use COMSOL (which is probably not an option, as you have already selected the ABAQUS), there is a useful tutorial about surface roughness:
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Hello everyone,
I'm doing a sheet metal forming simulation on Abaqus and it's my first time working on this software. After submitting the job on Abaqus several times via command prompt and CAE, the job is never completed. In the .sta file it just stops running and it doesn't show errors. The maximum ODB Field Frame Number of all my submitting attempts was 11 of 20 requested intervals, which is not enough.
Does anyone know what could be the reason? I'd be very thankful for any advice.
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Hi Seif,
I don't have much experience of Abaqus/Explicit. However, I've done a calculation using the information above. There seems to be 55151 increments between increments 2302740 and 2357891. It looks like the period analysed was 0.0099 sec, so each increment was 1.795(-7) sec. However, the file shows that the stable increment at element 68 was 1.648(-7). Can you try the following option:
*DYNAMIC, EXPLICIT, ELEMENT BY ELEMENT, SCALE FACTOR=0.9
Regards,
Simon
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The image attached is the representation of my application.
This is an assembly of three items (top plate, bottom plate and the 5 load cells).
The bottom plate is fixed and a load of 40 Kg is applied of the top face of the top plate.
The load cells are placed inside the bottom plate and the top plate rests on the top face of the load cells.
I have done the initial analysis in ANSYS workbench.
Need your help to find how much load / force is transferred to each load cells.
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this worked with one error and resolved it using the below link (misc were turned off in my case)..
Total load applied was 16Kgs..which can be ~160N.
Sum of the reaction forces in Y direction is 163 N.
So, i assumed it as the weight of the top plate and gravity are added.
But, i am in doubt that - i am applying loads as uniformly distributed load and the model and supports are symmetry. The loads are applied downwards (-y).
The reaction forces are not coming in pure -y. It is splitting up for x, y and z directions (image attached for reference)
What could be the reason. Any suggestions please...
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Hello, I am using the VUMAT that Abaqus provided for composite materials, but I face the error "Problem during linking - Single Precision Abaqus/Explicit User Subroutines."
Is there anyone that got this subroutine worked?
I would really appreciate any help.
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Hello
try to get assistance from the ABAQUS mailing list
Before posting search the archive of the list.
There is not much traffic on this list lately, and mails are sent after a long time only.
Get the file
http://imechanica.org/files/Writing User Subroutines with ABAQUS.pdf
Good luck
Frank
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I am using a plugin which calculates nodes based on a tolerance value. The tolerance values are inputted through a python script that I have added at the PYTHONPATH (Abaqus Working Folder, essentially).
Everytime I change the python script parameters, I need to restart and reload the plugin. The plugin updates the tolerance values from the python script only when Abaqus starts newly, not when it is running.
Is there a workaround for this?
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Very late, but in case others have the same problem you can use the reload method. E.g., if you have done
"import my_module"
then you can write:
"reload(my_module)"
to force the module to reload with the updated values.
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question solved and removed, thanks you
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Please be careful about the selection of no of steps.
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I am advising a researcher on using abaqus to run a mechanobiology simulation which requires the calculation of the interstitial fluid flow.  The calculation is based on an equation from Prendergasts work in mechanoregulation such that the stimuli on stem cells may be used to calculate their differentiation.  
The stimuli S is determined by empirical constants, the octahedral shear strain, and the interstitial fluid flow v in the extracellular environment of cells (see attached paper).  We are unable to find a setting in abaqus to output the interstitial fluid flow as a field output variable.  
We are using Abaqus/CAE 6.14, performing the FEA on a porous elastic material, and using pressure elements (C3D4P) for the meshing phase.  
In summary, we are asking for help in finding the interstitial fluid flow values as an output for a porous elastic material subject to a loading condition in abaqus, when a model consists of a scaffold structure and a poroelastic material representative of a granulation tissue where cells may differentiate according to the aforementioned stimuli.
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Hi Paul, I think I have the same problem as you. I want to know which variable should be used as fluid flow (FLVEL or CFF) in Abaqus?@Paul F Egan
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I am trying to model a free body with internal stresses in Abaqus CAE in order to look at what sorts of shapes it takes. I would like to have my body just suspended in space (and not anchored at some end for example), since all the behaviour I want to look is a result of internal forces. I haven't been able to do that so far and every time I try removing constraints from my model, the analysis stops converging. I would like to know if there is some way to analyse a free body in Abaqus, and if so, what would be the way to do it.
Thanks!
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Toan Nguyen Thank you! I'll try to find that.
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Would anyone know how to tell me how to make the nodes visible every time I select them? In my ABAQUS, the nodes are not visible, for example, when I create a set for them. When I display the group for theses nodes, those are not highlighted. I do not have this problem with elements or surfaces.
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Module Visualisation
Options>Common Plot Options>Labels
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