User login

Navigation

You are here

#ABAQUS

Post-doc and grad student positions available- Colorado School of Mines- fracture & renewable energy focus

Hello fellow mechanicians,

I have immediate and upcoming openings for graduate students and post-docs who have interest and experience in solid mechanics. I am especially in need of someone with Abaqus/FEA experience.

ebarbero's picture

Executing Abaqus from Scilab

Choose a channel featured in the header of iMechanica: 
Free Tags: 

I have managed to adjust a material property to get the best fit to the experimental response using fminsearch in MATLAB, but I lost access to free MATLAB so I have to use something else. I like Scilab, it works for everything I did with MATLAB except this. 

  

Scilab throughs and 'invalid handle' error when executing:

  dos('abaqus cae -nogui response.py','-echo');

at the line inside response.py:

  Job.submit(consistencyChecking=OFF)

 

It seems that Scilab opens a dos shell to execute abaqus but 'response.py' has this line inside it:

Element based surface for User Element

Choose a channel featured in the header of iMechanica: 
Free Tags: 

How does one define Element based surface for a User defined Element?

ebarbero's picture

Using Abaqus CZM, How can I get crack length for each increment?

When using CZM for crack propagation, for each CZM element, once the separation delta > delta_c, the adhesive is completely damaged, cannot transmit stress. delta_c is the separation on the right side of the bilinear or trapezoidal models. How can I get the length of the crack for each increment of applied displacement or load? I can see that the totally damage element disappear from the Visualization but I need a better way that gives me crack length, not just a picture that shows the crack longer for each increment.

Input file for the Single crystal plasticity subroutine Nonlinear Finite Elements for Continua and Structures by Ted Belytschko

Can anyone provide me with the input file for the example shown in the book Nonlinear Finite Elements for Continua and Structures by Ted Belytschko et al? The poly-slip, rate-dependent, single crystal plasticity VUMAT subroutine that is available publicly is attached in the following link. I have been trying to reproduce the results in Fig. 13.11 to Fig. 13.13. in the book, but am not successful in doing so. Can anyone please provide me with a working example input file for the problem?

https://gofile.io/d/xI9QSV

Can someone post an example of UMAT and VUMAT for the same elasto-plastic problem?

I want to understand how the stress update algorithm is modified for the different definitions of stress rate in ABAQUS/Standard and ABAQUS/Explicit formulations. I know the relationships, I just want to see how it's coded in a subroutine.

Also, the Hughes-Winget algorithm is used to update the stress defined by the Green-Naghdi stress rate by using the Jaumann rate. How to implement that in VUMAT? Can someone please post an example to clarify these aspects?

Eral Bele's picture

PhD Studentship in Mechanics of Materials at University College London

A PhD studentship is available in the Department of Mechanical Engineering at University College London, on the topic of "Detection and Identification of Damage in Composite Fibre/Metal Laminate Structures Using Guided Ultrasonic Waves". It is fully funded (fees + stipend) for UK citizens and EU citizens with UK residency (fees only for international students).

The academic group at UCL has an internationally leading profile and an exceptional publication record, and this project will provide numerous opportunities for high-profile publications and conference presentations. The project involves considerable interaction with other members of the research group, which has a very open, co-operative and friendly culture. The UCL laboratories are very well resourced with equipment, computers, consumables and all that is needed to perform research at the highest standard. The aim is to provide the best conditions for world-leading research.

Pai Wang's picture

Accepting applications to fully funded MS or PhD starting in 2021

We are looking for candidates to join the Utah Waves and Architected Materials Group (w.mech.utah.edu). We have fully funded openings for undergrads, MS and PhD. Both full-time and part-time researchers are needed.

ebarbero's picture

How do I count Keyword Blocks in the Abaqus input file?

Choose a channel featured in the header of iMechanica: 

The Abaqus documentation, available here:

https://abaqus-docs.mit.edu/2017/English/SIMACAEMODRefMap/simamod-c-inpu...

states the following:

Certain keywords must be used in conjunction with other keywords; forexample, the *ELASTIC and *DENSITY keywords must be used in conjunction with the *MATERIAL keyword. These related keywords must be grouped in a block in the input file; unrelated keywords cannot be specified within this block. 

Rudraprasad Bhattacharyya's picture

Why getting trouble with Abaqus UMAT subroutine when using interaction features like contact or tie?

I am implementing a constitutive relation in UMAT subroutine using the commercial software Abaqus. First, I tested the UMAT subroutine with 'one element model' first. Then I tested with comparatively bigger geometry. It worked fine. Now when I am trying to do a models involving contact, i.e. use of the 'Interaction module'. I am getting error of over-constraint warning for 'Split Tension test of concrete cylinder'. The same input file (except the material definition) is running on Abaqus perfectly with Mohr-Coulomb criteria. I can see a reasonable stress and strain contour.

Modeling Soil around pipeline with stiffeners in abaqus

I never worked with stiffeners in abaqus and now I should use theme. I want to model soil around pipeline with stiffeners. The stiffener behavior has 3 nonlinear components (x,y,z direction).

claudiosaul.lopes's picture

PhD position: multiscale computational mechanics of advanced composites

The Composites Materials Group (http://www.materials.imdea.org/groups/cm/) at IMDEA Materials, led by Dr. Carlos González and Dr. Cláudio S. Lopes, invites applications for a PhD student position in the field of multiscale computational mechanics of advanced composites. Candidates with interest and knowledge on computational damage mechanics, model development, numerical simulation and optimization methods for advanced composite materials and structures are strongly encouraged to apply.

Problem with defining corner BC/constraint

Hello all,

I'm trying to model the buckling of a shell structure under thermal load.

The structure is square-shaped.

The left edge must be kept straight. To achieve that, I applied MPC Tie Constraint for its nodes.

The bottom edge must be fixed so that the BC applied at its nodes was U1 = U2 = U3 = 0.

Temperature is applied as a predefined field.

However, when I run the simulation the corner that connects both edges deforms very strangely which makes me question how to model it.

I appreciate any input. Thanks.

About periodic BC for large mesh in ABAQUS

Choose a channel featured in the header of iMechanica: 

Hi all,

Leon Mishnaevsky's picture

Abaqus/Python - commands to find nearest node to a given point

Hi,
I need to write a python comman code to find a node (in a given set), nearest to a given point.
The code now looks as follows:
import sys
sys.path.insert(10, 
r'c:/SIMULIA/Abaqus/6.13-3/code/python/lib/abaqus_plugins/findNearestNode')
import nearestNodeModule
nearestNodeModule.hideTextAndArrow()
a = mdb.models['FibreModel'].rootAssembly
n1 = a.instances['Fibre0-1'].nodes

How to find normals stresses in the global x y z direction in ABAQUS?

I am trying to find normal stresses (in the global x-y-z direction) of individual layups (plies) in ABAQUS. While post processing I only find S11 S22 S12. Do I always have to use a transformation matrix to find my Sxx Syy and Sxy? Is there a GUI/ Command way to extract the stresses in each ply in xyz directions?

 

 

how to run a python script after each increment in abaqus.

Choose a channel featured in the header of iMechanica: 

hi,

I am doing static stress analysis. in my problem, I have to update my input file after each increment. so for updating the input file, I have to do some calculation depend on the output of the previous increment result. for these calculations, I have to call the odb file after each increment, do some calculations, update the input file and the process will go on. I have written a python script for the calculations from the odb file but don't know how to use this script after each increment.

 

thank you

Mohammed Bouchelarm's picture

Strain values transformed in a rotated x'y'-Cartesian coordinate system with ABAQUS

Dear All,

I'm trying to get strains in some specific points (along a path) from the xy-Cartesian coordinate system to a local x'y'-Cartesian coordinate system rotated through an angle (theta) which means transform the strains (Ex,Ey) to (Ex',Ey') as described in the attached figure, something I usually do manually with Mohr's circle and I wonder if I can do it directly with Abaqus ?

Thank you in advance !

Regards.

Mohammed.

 

Subscribe to RSS - #ABAQUS

Recent comments

More comments

Syndicate

Subscribe to Syndicate