what is the best Supersonic outlet boundary condition?
 

Hi, everyone,

I am simulating a supersonic jet flow out of a nozzle with OF 1.7. I used rhoPisoFoam and have some results shown in pictures attached.

However, the code end up with the errors:

I do not know why, please any one help to explain. what I should do ?


I am guessing i have not put proper boundary conditions. I used zeroGradient for U T and p. I am thinking they are not good for diamond shock wave? because the zeroGradient will try to remove the diamond shape, i.e. making all variables flat.

what kind of BC I should put?

Yu

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ourant Number mean: 0.000303193 max: 0.103399
Time = 0.000269595

diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for Ux, Initial residual = 5.88706e-06, Final residual = 8.42049e-18, No Iterations 3
DILUPBiCG: Solving for Uy, Initial residual = 4.656e-05, Final residual = 6.64296e-16, No Iterations 3
DILUPBiCG: Solving for Uz, Initial residual = 1.7914e-05, Final residual = 1.32137e-16, No Iterations 3
#0 Foam::error::printStack(Foam::Ostream&) in "/opt/openfoam170/lib/linux64GccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int)DILUPBiCG: Solving for h, Initial residual = 9.35158e-06, Final residual = 2.73225e-17, No Iterations 3
DICPCG: Solving for p, Initial residual = 1.19697e-05, Final residual = 5.54901e-11, No Iterations 1
DICPCG: Solving for p, Initial residual = 8.38527e-11, Final residual = 8.38527e-11, No Iterations 0
DICPCG: Solving for p, Initial residual = 8.38527e-11, Final residual = 8.38527e-11, No Iterations 0
DICPCG: Solving for p, Initial residual = 8.38527e-11, Final residual = 8.38527e-11, No Iterations 0
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 1.07636e-10, global = -4.12859e-13, cumulative = 2.3783e-06
DILUPBiCG: Solving for h, Initial residual = 1.90256e-08, Final residual = 2.03845e-17, No Iterations 3
in "/opt/openfoam170/lib/linux64GccDPOpt/libOpenFOAM.so"
#2 in "/lib/libc.so.6"
#3 Foam::hPsiThermo<Foam::pureMixture<Foam::sutherlan dTransport<Foam::specieThermo<Foam::hConstThermo<F oam::perfectGas> > > > >::calculate() in "/home/yu/OpenFOAM/yu-1.7.0/lib/linux64GccDPOpt/libbasicThermophysicalModels.so"
#4 Foam::hPsiThermo<Foam::pureMixture<Foam::sutherlan dTransport<Foam::specieThermo<Foam::hConstThermo<F oam::perfectGas> > > > >::correct() in "/home/yu/OpenFOAM/yu-1.7.0/lib/linux64GccDPOpt/libbasicThermophysicalModels.so"
#5
in "/opt/openfoam170/applications/bin/linux64GccDPOpt/rhoPisoFoam"
#6 __libc_start_main in "/lib/libc.so.6"
#7
in "/opt/openfoam170/applications/bin/linux64GccDPOpt/rhoPisoFoam"