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Old   January 1, 2013, 13:31
Default combustion mechanism
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v
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Hi Foamers,
I'm working on a simulation of combustion in porous media with my new solver porousReactingFoam . for global mechanis ch4 is correct but for 4 step mechanism ch4 is divergence.
error is termonal :
--> FOAM FATAL ERROR:
Too many integration steps

From function ODESolver::solve(const ODE& ode, const scalar xStart, const scalar xEnd,scalarField& yStart, const scalar eps, scalar& hEst) const
in file ODESolvers/ODESolver/ODESolver.C at line 107.

FOAM exiting

Who can help me?
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Old   January 2, 2013, 11:42
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Adhiraj
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Hi,
this error means that the ODE solver that you are using to solve the 'chemistry' is unable to find solutions even after a large number of steps.
Can you try with:
a) a smaller time step (in controlDict)
b) a different ODE solver?
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Old   January 2, 2013, 16:09
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dear adhiraj
the time step is 10e-6
I am an energy source in the Appropriate timestep I use to simulate ignition.
after ignition the velocity in cells goes up very high(about 100 scale) and solution is divergent.
Courant number was controlled by adjusting the timestep but not divergent. and the temperature of the solution increases.
comment:
for global mechanism ch4 is correct but for 4 step mechanism ch4 is divergence For the same conditions.!!

Best Regards
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