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I want to model underwater explosion in Abaqus. there is an example in abaqus help by the name of "9.1.3 Response of a submerged cylinder to an underwater explosion shock wave" which is very similar to what I'm trying to model. the problem is that i apply incident wave(planer/spherical/Undex) on the both structure and acoustic medium but i couldn't submit the model and it says " the model attributes wave formulation type must be set when using an incident wave interaction (Int-1 for example)".

I would appreciate it if someone could help me with this. thanks. 

Hi everyone, I'm new here :)



I'm French so my english might not be perfect. I'm attending a MSc in mechanical engineering.



I'm currently struggling to activate "User defined field" in the material windows within abaqus CAE.



How can I do it ? It should be easy but I can't find the solution...Consequently I can't use the subroutine I wrote.



thank you for your help, I need it :)

Hello.

At the moment I'm trapping in finding a solution to determing the critical/buckling load for this two-stepped column as shown in the picture. In the middle it has an extra support. Could anyone please help me with this exercise, or give me some advice on further references?

Thanks a lot!

Dear All,

Does Anybody know how to recover the wall clock time of an Abaqus/explicit analysis? I do not understand why for implicit analyses is easy (log file) while for explicit there is no information.

Thank you,

Mauro. 

hello

i have modeled a steel cylinder subjected to underwater explosion according to an article model by ABAQUS.

but there is a differece between displacement curve of my model and the article model.

you can see displacement curve of article model is oscillating around 0.8 mm and -0.8 mm but the same curve in my model is oscillating around 0.0 axes.  (Images are attached to this post)

i think its reason is plastic deflection of article model (0.8 mm) .

i should mention that i defined plastic properties of material too.

Hello Everyone,

I am simulating contact of a sphere with a soft elastomer (Hertz contact). Unlike the hertz contact, I will like to simulate large deformations. My model is a 2D axisymmetric model and the load is displacement controlled. The current model fails at total time/freq ~ 0.84. I have tried refining my mesh and have reduced the increment size and increased the number of increments. Currently, step my parameters are:

 Max. number of increments: 200000 and Increment size:0.005/1E-5/0.01

 Nlgeom is On because of the large deformation.

I'm trying to develop yield surface of a material for a particular value of hydrostatic stress(since CDP model uses drucker-prager hypothesis).. In user manual, it is given that, for Kc value of 1, i should get a circle, and for Kc value of 0.667, i should get a shape of inverted triangle in deviatoric plane.. But I have tested for 3 values of Kc, 0.667, 0.9 and 1, for all, i'm getting the same inverted triangle in the deviatoric plane. 

*Concrete Damaged Plasticity 

22., 0.33, 1.16, 0.667, 0. 

Dear friends,

I am working on vufiled subroutine for
abaqus. I already have a named common block statement in my vfriction
subroutine. I need the values from the common block be read in vufield
subroutine and passed further / saved to a field variable to be able to
plot a contour plot.

Can anyone share his ideas about the coding or have an advice for me?

Paul