[foamer]

Hi

i am investigating a case by using the shockTube tutorial, (rhoCentralFoam solver).

My problem is that i get an error message when i am running the simulation. the simulation starts to run, but after a short time i receive an error message. the problem is that i do not know what it means.

An excerpt of the two last iterations and the error message i receive is:


diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoUx, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoE, Initial residual = 0, Final residual = 0, No Iterations 0
ExecutionTime = 0.12 s ClockTime = 1 s

Mean and max Courant Numbers = 0.0993913 0.2
deltaT = 1e-05
Time = 0.0001

diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoUx, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoE, Initial residual = 0, Final residual = 0, No Iterations 0
ExecutionTime = 0.13 s ClockTime = 1 s

#0 Foam::error:rintStack(Foam::Ostream&) in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so"
#2 in "/lib/libc.so.6"
#3 Foam::sqrt(Foam::Field<double>&, Foam::UList<double> const&) in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so"
#4
in "/opt/openfoam171/applications/bin/linux64GccDPOpt/rhoCentralFoam"
#5
in "/opt/openfoam171/applications/bin/linux64GccDPOpt/rhoCentralFoam"
#6 __libc_start_main in "/lib/libc.so.6"
#7
in "/opt/openfoam171/applications/bin/linux64GccDPOpt/rhoCentralFoam"
Floating point exception


I have a fealing that the errouniosity is based on the changes i did to the setFieldsDict file. My setFieldsDict file looks like:

defaultFieldValues ( volVectorFieldValue U ( -1000 0 0 ) volScalarFieldValue T 349 volScalarFieldValue p 100000 );

regions ( boxToCell { box ( 0 -1 -1 ) ( 5 1 1 ) ; fieldValues (volVectorFieldValue U ( 1000 0 0 ) volScalarFieldValue T 349 volScalarFieldValue p 100000 ) ; } );


i will have deeply appreciated if someone could have explained to me what the error message means and what i can do to cope with this problem.

Alex

[foamer]

Hi

I think i know what is the problem.
When i check the pressure in time folder 0.001 i eventually get negative pressure. So i guess this has to do with the numerics in the algorithm or so, that it cannot handle it.


Alex

[Farshad_Noravesh]

Hi,

Did you solve the problem? I am still getting your error. Even when i use other tutorials of rhoCentralFoam i still get the same error.

please help me.

Kind Regards,

Farshad

[foamer]

Originally Posted by Farshad_Noravesh

Hi,

Did you solve the problem? I am still getting your error. Even when i use other tutorials of rhoCentralFoam i still get the same error.

please help me.

Kind Regards,

Farshad

Farshad, i think the velocity is too high...if you lower the velocity to 900 m/s it should be able to run...

Hope this will work for you



alex

[immortality]

may be the problem is from turbulency

[foamer]

Originally Posted by immortality

may be the problem is from turbulency

Ok, could you please specify that a little more ?


alex

[immortality]

I have the same problem.it seems the equations of rho don't solve at all.because rho,rhoUx,rhoUy,rhoUz and rhoe are zero in my run.
I don't whats the cause of the problem.

[praveen]

Try reducing cfl number and/or time step.

[vwibaut]

Hi all,

I'm solving the flow in a nozzle and I have the same problem that foamer

My problem is that i get an error message when i am running the simulation. the simulation starts to run, but after a short time i receive an error message. the problem is that i do not know what it means.

Just reducing the velocity solves your problem?

Regards