multiSolver released
 

Hi Foamers,

I am pleased to announce the release of multiSolver, an extension to OpenFOAM that allows you to run numerous solvers in sequence on a single dataset.

Why would you need that?

• Arbitrarily changing boundary conditions mid-run;
• Modelling multi-step processes in a single application (e.g. injection & settling);
• Modelling a problem characterized by 2 different timesteps (e.g. stirring & biochemical reactions).

See this page on the wiki for further details:

http://openfoamwiki.net/index.php/Contrib_multiSolver

Share and enjoy!

Parallelization?
 

Are parallel runs supported yet? I'm using OF-1.6-ext and this would be fantastic for my applications.

Dan

Hi Dan,

No, it isn't. I haven't worked with parallel very much, so I'm not familiar with the directory structure and how the processors communicate. I don't forsee it being challenging, but I don't have the time right now. I would be open to collaborating on its development, though!

I expect to be putting mesh motion in this summer. I'll also have an updated version with minor changes before the 6th workshop.

-Dave

I would be willing to collaborate on this one to get it working. I will take a look at the code and see if I can offer any help. It looks like a fantastic tool and could definitely be worth getting it to work in parallel. I'll get into it starting tomorrow.

Dan

Grand! I've sent you a PM with some more information. I hope we can get this working!

multiSolver now fully supports parallel simulations.

Hello. First of all, great work with this solver!
I do seem to have hit an obstacle though. You say it supports parallel processing. I don't seem to be able to figure out how to get the solver to run. I have decomposed the case as explained on the WIKI page, but when I try to run the case using mpirun .... it won't run. It seems that there are no "0" directories in the processor directories. I guess I am just missing something trivial, but I haven't worked it our yet. Maybe you can give me a tip?

It sounds like you aren't using a multiSolver-enabled solver. What solver are you using? The only publicly available one is multiSolverDemo, which came with the installation. The wiki page also shows how to easily create a multiSolver-enabled application.

If you are using the correct solver... then what errors are you getting?

OK, here goes. I compiled my own multisolver called multiBubbleSolver. Incidentally, it works fine on a single processor. Then I decompose as per instructions on the wiki. then I input:


mpirun -np 4 multiBubbleSolver -parallel


and I receive this:


[1] --> FOAM FATAL ERROR:
[1] Initial time directory missing for solver domain [interFoam1]. Expecting "/home/peter/OpenFOAM/peter-1.7.x/run/BUBBLES/processor1/multiSolver/interFoam1/initial/0"
[1]
[1] From function multiSolver::checkTimeDirectories
[1] in file multiSolver/multiSolver.C at line 320.

...The rest of the errors seem to be caused by the missing directory.

The same thing happens if I try using multiSolverDemo in parallel.The directory structure in the proc* folders is as follows ("0" directory missing):

processor*
-constant
-system

Hi Peter, I've managed to duplicate the issue on my machine. I'll try to resolve it as quickly as I can, but I have to leave for work soon. I'll let you know...
-Dave

Hi Peter, I've got a work-around you can try for now... the bug fix should come within a few days. Edit the controlDict file (not the multiControlDict), and set:

startFrom: startTime;
startTime: -1;

Then try the long decompose command in the wiki. I have to head off to work now. Hope it works!

Nice job! works fine for the demo; I'll have a go at my case later on. Thanks.

The bug fix has been completed. Parallel decomposing should nolonger omit the initial directories!