CalculiX vs Code-Aster


I posted a query in the Code-Aster forum a few days back regarding the differences between the two codes i.e., CalculiX and Code-Aster. Please take a look and share your comments (if any).

Here’s the link to the post: CalculiX vs Code-Aster / Code_Aster usage / Code_Aster forums

PS: I do not intend to disrespect the user/developer community of either code. I am simply looking for opinions to make a sound decision before I move forward.



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  1. I am afraid it was not a good idea to ask Code-Aster (CA) users what they are thinking about any other program. Just go to the any Ford/VW/Toyota/etc. fans forum and ask them what they are thinking about any another car maker. It is easy to predict the response.

  2. It is methodologically incorrect to compare two totally different programs “in general”. As you mentioned in your post in the CA forum, everything depends on your application field.

  3. I have switched from Salome/CA to CalculiX due to very simple reason. CA has extremely steep learning curve and it is a total disaster from educational point of view. On the other hand, an average mech. engng student needs an hour or two to start work with CalculiX using extremely intuitive PrePoMax as a pre- and post processor. Thus, for educational purposes (my application field), CCX+PrePoMax is a very good choice. It does not mean it is the best program “in general”.

  4. Most of industrial FEA is still linear elastic problems. In such a case, small CalculiX with very good PasTiX solver is robust, cost effective and easy-to-use solution for many small and medium size companies. These CalculiX users do not write posts to this discussion group just because they have no problems with CalculiX at all. On the other hand, 17% of the posts at CA forum are about installation problems with this huge and complex program.


I agree totally with your comments, I am very conscious about that Code_Aster is more powerfull than CCX, but for most of the cases that I work (industrial and teaching in my case), CCX is enough, accurate and easier (combined with Mecway or Prepomax) even than some comercial programs.


What Sergio said.

Also, I think most people would be astonished at the level that Calculix gets used in industry, without fanfare.

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Wow, I just looked at the comments you linked. People get very personal about this stuff I guess.
Bhanu, we have been using the Calculix solver, often coupled with Mecway as the front-end, successfully in an industrial setting for about 5-6 years. No issues.

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Thanks @i_rokach

  1. I guess you’re right but there wasn’t any common forum I guess. Well, that’s that. :slight_smile:
  2. Yes, it does depend on a lot of things.
  3. I can’t say much about CA, but since I’ve been trying out some example problems in CalculiX for quite some time now, I’d say I am rather comfortable with CalculiX at least for now.
  4. Yes, since I also come from an industrial background, I know that most of the FE analyses are linear elastic only.

Anyway, I guess I’ll perhaps stick with CalculiX for now, and switch to CA if required based upon my problem.

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Yes, I felt that too. People do get personal sometimes. :slight_smile:

Anyway, thanks @JohnM for your feedback.

Could you also give me a brief list of the type of problems that you’ve tried/worked out with CalculiX?

Essentially, I’d like to know whether you’ve handled cases of extreme plastic compression as in impact/blasts using CalculiX particularly because that’s very much related to the problem I have.


Thanks @SergioP for your feedback.


I did some test on impact and lots on rubber parts (Goma :: 4p-ingenieria) with big deformations and multiple contacts, in my humild experience in both areas CCX will not perform well in extreme cases. Have seen that Code_Aster has a remeshing feature, that could be needed in case of extreme deformations. On the other side, I have perfomed using Abaqus in the past simulations on rubber parts were remeshing was not needed using hexa elements with reduced integration.

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We do deal with plasticity, but I do not think it is the level that you are considering. That’s not to say calculix doesn’t handle that stuff, I’m simply not aware. Is this high-speed metal forming?

I’ve been doing nonlinear stress and modal analysis with netgen mecway and ccx. it is easy fast and works well in my opinion.

the comments on your other forum link i don’t agree with. im not aware of any software product that guarantees the results. it’s a legal issue as well. it’s always up to the user to guarantee their own results. the liability is on the user not the software vendors.

the other point about two devs vs a community is ridiculous. ccx seems to be mostly one dev rather than two. regardless, what matters is the software not how many monkees it takes to screw in a lightbulb.

for your specific blast application, you may want to look at explicit integration fea rather than implicit. i don’t know if ccx can do those kinds of problems.

also, on the linear analysis being common. it used to be decades ago. however, ccx makes nonlinear so easy and fast that is all i run now. if you need accurate displacement then nonlinear is the way to go. even for cases well below yield.

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Thanks @SergioP

Yes, the remeshing feature could be needed in my case although I am not sure at this point.
And, about ABAQUS, I’ve also done some cases of extreme compression and yes, there is no requirement of remeshing if reduced integration elements are used (if I remember correctly, the same goes true if we use 1st order elements).


Yes @JohnM, it is almost like high-speed metal forming.



I’ve had no experience working with Mecway (nor with PreProMax @i_rokach) but given my experience with proprietary tools such as HyperWorks and ABAQUS, I guess these should come around handy.

And yes, I agree that the guarantee lies with the user. And it surely does not matter how many devs there are as long as the code works fine.

Anyway, thanks for your feedback. :slight_smile:

Codes like LS Dyna and Abaqus Explicit are designed for high rate strain. They have the material models and the right integration schemes. Years ago I met with Glenn Daehn, the professor who headed up the Ohio State Impulse forming research using ballistic and electromagnetic methods. His grad students were using LS Dyna.

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both FE software are GPL and should not against each others. CalculiX CGX has a feature to export element and node sets in Code_Aster format, also UNV mesh and node groups generated by Salome preprocessor (modeling & meshing) dedicated specially for Code_Aster can be exported to CalculiX input files.

User has possibilities’ to switch between of both FE solver if required to further study the area of interested (e.g analysis type, material laws, element formulations).


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