Coupling multiphysics

Question

Hello,

I just happened to learn about this software.

I have a lot of experience in FEM, but I am wary of investing my time if I am not sure if my needs are going to be met.

My question is whether or not it is possible to easily couple a continuum damage model with let us say flow or transport equations. From my first look at the documentation it seems feasible to couple flow and transport as it is a matter of coupling well-known PDEs, but it is not obvious if specialized models such as continuum damage can be implemented by modifications to elasto-plastic or nonlinear elastic models.

And my second question is what is technically unique about Fenics considering that there are so many open source software and also commercial software which can handle multiphysics (apart from cost aspect).

Thank you for your time.

Sanny Gray

Answer 1

Hi Sunny,

Personally, I can't say that I have any experience with continuum damage but I did make the jump from COMSOL to FEniCS last year so might ramble a little. FEniCS is open source, so you can do whatever you want to do with it. If you can write your model in a PDE you have a chance of solving it. If it doesn't solve, you might have to get your hands dirty to make it solve. If it still doesn't then you can look at the commercial codes that do solve it and copy the technique in FEniCS (and then share it for us to benefit!). The commercial codes (like COMSOL) have a bigger 'infrastructure' in place, making a lot of things easier but also taking away your freedom to think outside the black-box. It's like moving to Linux from Windows; all of a sudden you need to learn an awful lot!

I like FEniCS for its generality and especially its symbolic logic. That's my personal approach though. My model run faster on COMSOL and are frankly much easier to get working but I can do more neat stuff with and through FEniCS. With the commercial codes you have a nice, big and safe playground, but with FEniCS you have the world (or at least an entrance to it!).

Comments

Hello Mwelland,

Thank you for your quick answer and it is most helpful.

It is coincident that I am also planning to shift from COMSOL although COMSOL is the most powerful GUI based PDE solver I have seen so far. But yes some things cannot be done and one has to continue to subscribe hoping that one day they will implement models that is of interest to my needs.

SG

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I found COMSOL great to 'get your feet wet' and to see what FEM can do before having to learn the nitty-gritty details...
If you are programming in COMSOL with the weak form directly then the jump isn't so bad (although I did find a lack of FEniCS multiphysics demos).

Good luck!

Mike