CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   OpenFOAM (https://www.cfd-online.com/Forums/openfoam/)
-   -   need for an unsteady implicit solver suitable for large timestep (https://www.cfd-online.com/Forums/openfoam/76386-need-unsteady-implicit-solver-suitable-large-timestep.html)

dinonettis May 24, 2010 14:11

need for an unsteady implicit solver suitable for large timestep
 
Dear all,

at the moment I'm facing the simulation of a flow around a sphere. The Reynolds is very low (27), therefore pressure and velocity are steady.
However the next step consists in performing a simulation in which the temperature at the inlet is linearly changing in time. Therefore I have to use a transient solver.
Due to the fact that the flow is steady (no risk of changing the physics of the flow) and due to the huge amount of time I have to simulate, I think the best solution is a very large time step. That's not possible with icofoam since it will take approximately 400 days to obtain the solution!!!! But I hope my PhD will end up by that time :)))
Somebody knows an alternative solver able to do that?!?!?
Thanks in advance,

Dino

dinonettis May 25, 2010 12:40

I already tried pimpleFoam, but it seems to be not appropriate since starting from a converged solution, in terms of pressure and velocity, and using a Co=2 the pressure residuals are fixed to 0.8!!!!
Any suggestion is well accepted!!

stawrogin May 26, 2010 06:57

Hi Dino,

maybe this thread helps:

http://www.cfd-online.com/Forums/ope...ime-steps.html

stawrogin


All times are GMT -4. The time now is 08:36.