Static General analysis and Dynamic Explicit analysis in ABAQUS

[Suthama]

Dear everyone,

Could anyone please explains to me how difference between Static General analysis and Dynamic Explicit analysis in ABAQUS?

Can we use both types of analysis to solve the same problem?

I have already created subroutine VUMAT for Dynamic Explicit analysis. So, is it possible to use the same code (same algorithm) for creating UMAT in Static General analysis?

Thank you very much indeed
Sutham A.

 

[IceBreakerSours]

The answer to "Can we use both types of analysis to solve the same problem?" is yes and no depending on the problem. For example, if it is an impact type of a problem, in all probability, you are better off choosing Explicit. However, before using Explicit, typically, (and more experienced users are welcome to correct me) you want to make sure the static solution makes sense.

http://www.eng-tips.com/faqs.cfm?fid=376

 

[pirs]

Hi Sutham,

I have used both Static General and Dynamic Explicit to model the same event in ABAQUS. In my particular case, I have decided that using explicit provides a much better approach to the results, since I wanted to model time dependent events, even though the time scale is rather long (quasi-static events).

Someone else might correct me here, but my view on it is: a static analysis divides your load/displacement/etc. into small increments and performs an incremental analysis by increasing the solicitation value by each increment; on a dynamic analysis, you define time dependent load/displacement/etc. functions and these will be incremented in time.

This is mostly due to the fact that Static General Analysis only allows you to apply displacement or loads directly to the nodes/elements of your model in the same step. Imagine that those nodes suffer excessive deformation and the way your load is transferred/applied is changed because of this. That's where a dynamic analysis will gain the upper-hand, if you couple it with contact and other advanced formulations.

If you want to further compare the alternatives, it would be interesting if you could tell us exactly what you will be modelling.

Best regards

 

[Suthama]

Thank you very much for every information you gave me, I am very appreciate.
In my research, I need to create subroutine UMAT for Rousselier damage model.
I have already done it on VUMAT (for dynamics), but now I need to transfer my code to UMAT (for static problem).
However, I got stuck on this step for long, because I haven’t known yet how to define the Jacobian (the consistent tangent modulus) for this theory.
Could anyone provide me the information about this term (the jacobian of Rousselier damage model)?

Thank you very much
Sutham A