CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM

k-Epsilon model for compressible air

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 7, 2021, 13:23
Default k-Epsilon model for compressible air
  #1
New Member
 
Carlos
Join Date: May 2017
Posts: 16
Rep Power: 8
Ricardo1992 is on a distinguished road
Hello all,

I hope that you may help me. I am building a venturing nozzle based on the "Supersonic flow over a forward-facing step "([URL="https://www.openfoam.com/documentation/tutorial-guide/3-compressible-flow/3.2-supersonic-flow-over-a-forward-facing-step"]).

The code runs well for my geometry. I have added a sketch of my geometry and the names of the patches.

Now, I am trying to add a k-Epsilon turbulent model to account for turbulence. However, I am struggling a lot with this.

The case crushes after 4 time steps:



Courant Number mean: 0.00183398 max: 0.296916
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCGStab: Solving for Ux, Initial residual = 0.848478, Final residual = 7.41534e-07, No Iterations 1000
DILUPBiCGStab: Solving for Uy, Initial residual = 0.905086, Final residual = 9.39327e-06, No Iterations 1000
DILUPBiCGStab: Solving for e, Initial residual = 0.357641, Final residual = 8.74872e-10, No Iterations 828
DILUPBiCGStab: Solving for p, Initial residual = 0.999241, Final residual = 1177.16, No Iterations 1000
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 199.308, global = 4.46821, cumulative = 4.46821
DILUPBiCGStab: Solving for p, Initial residual = 0.979981, Final residual = 7.17817e+07, No Iterations 1000
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 88132.4, global = -30178.3, cumulative = -30173.8
DILUPBiCGStab: Solving for epsilon, Initial residual = 1, Final residual = 9.78935e-06, No Iterations 1000
bounding epsilon, min: -6.89085e+36 max: 3.41706e+36 average: 4.37867e+32
DILUPBiCGStab: Solving for k, Initial residual = 0.999482, Final residual = 4.61607e-11, No Iterations 6
bounding k, min: -5.46211e+31 max: 6.0254e+29 average: -3.7871e+26
#0 Foam::error:rintStack(Foam::Ostream&) at ??:?
#1 Foam::sigFpe::sigHandler(int) at ??:?
#2 ? in "/lib64/libc.so.6"
#3 Foam::nutUSpaldingWallFunctionFvPatchScalarField:: calcUTau(Foam::Field<double> const&) const at ??:?
#4 Foam::nutUSpaldingWallFunctionFvPatchScalarField:: calcNut() const at ??:?
#5 Foam::nutWallFunctionFvPatchScalarField::updateCoe ffs() at ??:?
#6 Foam::fvPatchField<double>::evaluate(Foam::UPstrea m::commsTypes) at ??:?
#7 Foam::RASModels::kEpsilon<Foam::EddyDiffusivity<Fo am::ThermalDiffusivity<Foam::CompressibleTurbulenc eModel<Foam::fluidThermo> > > >::correctNut() at ??:?
#8 Foam::RASModels::kEpsilon<Foam::EddyDiffusivity<Fo am::ThermalDiffusivity<Foam::CompressibleTurbulenc eModel<Foam::fluidThermo> > > >::correct() at ??:?
#9 ? at ??:?
#10 __libc_start_main in "/lib64/libc.so.6"
#11 ? at ??:?
Floating point exception (core dumped)

I think that my problem is in the BC for the turbulence.

I have attached all the files in this message. I am wondering if someone could help me. I am not sure what I am doing wrong.

Last edited by Ricardo1992; June 9, 2021 at 09:51.
Ricardo1992 is offline   Reply With Quote

Reply

Tags
compressible air, k-epsilon model, openfoam, turbulence


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Question about adaptive timestepping Guille1811 CFX 25 November 12, 2017 17:38
Overflow Error in Multiphase Modelling with Two Continuous Fluids ashtonJ CFX 6 August 11, 2014 14:32
Jump in epsilon values near the wall : low re k-epsilon model malaboss OpenFOAM Verification & Validation 1 February 1, 2013 16:36
K - epsilon VS SST turbulence model Maicol Main CFD Forum 0 November 30, 2012 16:25
air and water vapour mixture - multiphase model Saba FLUENT 0 February 10, 2009 12:05


All times are GMT -4. The time now is 11:30.