[Gloster]

Hello,

I am trying to model Subcooled Nucleate Flow Boiling in a geometry (its a HyperVapotron Geometry). I am using 'chtMultiRegionTwoPhaseEulerFoam' to do that, but I am getting some errors.

wireframe.png
interFace.png
Here are the snapshots of the geometry. First image has the whole geometry. Upper region is where the fluid will be flowing and the lower region is solid with heat flux applied at lowermost surface. The interface between the solid and fluid region can be seen in the second image, with the fluid region.

checkMesh.log
I do have a lot of nonOrhtogonalFaces, but I am not sure how I can improve the meshing. Meshing was done using Gmesh with 'Frontal-Delaunay' for 2D, 'Delaunay' for 3D and all the elements are hexahedral. I did try transfinite surfaces and curves, but that resulted in a worse mesh.

Here are the solutions schemes implemented for both fluid and solid.
fluid -> fvSolution
fluid -> fvSchemes
solid -> fvSolution
solid -> fvSchemes
controlDict

The boundary conditions are set like this
constant -> fluid -> polymesh -> boundary
constant -> solid -> polymesh -> boundary
fluid -> P
fluid -> p_rgh
fluid -> T.gas
fluid -> T.liquid
fluid -> U.gas
fluid -> U.liquid
solid -> T

Since the operating pressure is 6 bar, I have also change SaturationModel file in phaseProperties of the fluid for obtaining data for saturation temperature at 6 - 7 bars.

Other boundary conditions can be found here,
0

The errors are,

Solving for fluid region fluid
MULES: Solving for alpha.gas
MULES: Solving for alpha.gas
MULES: Solving for alpha.gas
alpha.gas volume fraction = 0.937255064283  Min(alpha1) = -1.38750386353e-19  Max(alpha1) = 1
Constructing face momentum equations
Tf.gasAndLiquid: min = 300, mean = 385.007573817, max = 728.619819
wDmdt.gasAndLiquid: min = 0, mean = 0.011488113694, max = 1.6099437385, integral = 13.2924044626
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.769658453748, Final residual = 0.000159982701324, No Iterations 4
DILUPBiCGStab:  Solving for h.liquid, Initial residual = 0.0792935784073, Final residual = 9.42949921413e-06, No Iterations 1
Tf.gasAndLiquid: min = 300, mean = 385.006367246, max = 728.625002025
wDmdt.gasAndLiquid: min = 0, mean = 0.011488125315, max = 1.60995441831, integral = 13.2924236763
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.245396682818, Final residual = 0.000243116637209, No Iterations 3
DILUPBiCGStab:  Solving for h.liquid, Initial residual = 0.0134072238656, Final residual = 6.01632147788e-07, No Iterations 2
Tf.gasAndLiquid: min = 300, mean = 385.006426816, max = 728.625891823
wDmdt.gasAndLiquid: min = 0, mean = 0.0114881272789, max = 1.60995420022, integral = 13.2924262292
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.114826043899, Final residual = 0.000110468946899, No Iterations 3
DILUPBiCGStab:  Solving for h.liquid, Initial residual = 0.0126222930116, Final residual = 5.78601338762e-07, No Iterations 2
Tf.gasAndLiquid: min = 300, mean = 385.006660493, max = 728.626044581
wDmdt.gasAndLiquid: min = 0, mean = 0.011488126944, max = 1.60995420385, integral = 13.2924257445
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.058333433551, Final residual = 5.31733271894e-05, No Iterations 4
DILUPBiCGStab:  Solving for h.liquid, Initial residual = 0.00227866378772, Final residual = 5.86043750865e-07, No Iterations 2
GAMG:  Solving for p_rgh, Initial residual = 0.012473316537, Final residual = 1.34548207234e-05, No Iterations 2
GAMG:  Solving for p_rgh, Initial residual = 0.0031495611284, Final residual = 1.91443588528e-08, No Iterations 4
bounding km, min: 9.91228736344e-16 max: 1401.50231331 average: 0.541346208152
bounding epsilonm, min: 7.01798913415e-23 max: 7503119.25567 average: 1466.80837448
DILUPBiCGStab:  Solving for epsilonm, Initial residual = 0.10232014643, Final residual = 4.58100778058e-17, No Iterations 1
bounding epsilonm, min: -64691.4214983 max: 7361110.28939 average: 1842.31770029
DILUPBiCGStab:  Solving for km, Initial residual = 3.33031606009e-12, Final residual = 3.12861962241e-15, No Iterations 1
bounding km, min: -9.78309774245e-05 max: 1389.85546657 average: 0.548365275101

Solving for solid region solid
DICPCG:  Solving for h, Initial residual = 0.00556165287296, Final residual = 3.05363273092e-14, No Iterations 1
Min/max T:1051.14070287 6338.15210826
ExecutionTime = 630.82 s  ClockTime = 632 s

Courant Number max: 0.628375604754
Region: solid Diffusion Number mean: 9.99418457892e-07 max: 0.000109829107555
deltaT = 0.000226405244948
Time = 0.0135132


Solving for fluid region fluid
MULES: Solving for alpha.gas
MULES: Solving for alpha.gas
MULES: Solving for alpha.gas
alpha.gas volume fraction = 0.93725506986  Min(alpha1) = -6.24472412882e-20  Max(alpha1) = 1
Constructing face momentum equations
Tf.gasAndLiquid: min = 300, mean = 385.006618672, max = 728.626069516
wDmdt.gasAndLiquid: min = 0, mean = 0.0114881623143, max = 1.60972724483, integral = 13.2924355664
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.407363573561, Final residual = 9.9532121853e-05, No Iterations 3
DILUPBiCGStab:  Solving for h.liquid, Initial residual = 0.209281059899, Final residual = 6.35287785314e-07, No Iterations 1
Tf.gasAndLiquid: min = 300, mean = 385.011809881, max = 713.745431897
wDmdt.gasAndLiquid: min = 0, mean = 0.0114881787379, max = 1.60974085018, integral = 13.2924658693
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.870720891054, Final residual = 0.000650370809786, No Iterations 2
DILUPBiCGStab:  Solving for h.liquid, Initial residual = 0.721491795845, Final residual = 1.0568977799e-07, No Iterations 1
Tf.gasAndLiquid: min = 300, mean = 385.005413476, max = 710.619046384
wDmdt.gasAndLiquid: min = 0, mean = 0.0114881798905, max = 1.60974054678, integral = 13.2924669804
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.887456694416, Final residual = 0.000853586270927, No Iterations 1
DILUPBiCGStab:  Solving for h.liquid, Initial residual = 0.999988884631, Final residual = 1.32588102639e-08, No Iterations 1
Tf.gasAndLiquid: min = 300, mean = 385.004601251, max = 709.962346728
wDmdt.gasAndLiquid: min = 0, mean = 0.011488179654, max = 1.60974055301, integral = 13.2924666603
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.885418166755, Final residual = 0.000627908855335, No Iterations 2
DILUPBiCGStab:  Solving for h.liquid, Initial residual = 0.999991785189, Final residual = 7.03626310296e-09, No Iterations 1
GAMG:  Solving for p_rgh, Initial residual = 0.0101959473612, Final residual = 4.40104762737e-06, No Iterations 2
GAMG:  Solving for p_rgh, Initial residual = 0.00270819127908, Final residual = 8.90916204024e-08, No Iterations 3
bounding km, min: 9.91395104984e-16 max: 1389.85546657 average: 0.548366855183
bounding epsilonm, min: 7.01798913415e-23 max: 7361110.28939 average: 1457.22239958
DILUPBiCGStab:  Solving for epsilonm, Initial residual = 0.0428890843044, Final residual = 2.68875902701e-08, No Iterations 1
bounding epsilonm, min: -42.6501524032 max: 7250734.45564 average: 1818.8925837
DILUPBiCGStab:  Solving for km, Initial residual = 0.27193697808, Final residual = 6.70637375883e-05, No Iterations 12
bounding km, min: -4.29455984982e+17 max: 96939264477.1 average: -1.61727214698e+13

Solving for solid region solid
DICPCG:  Solving for h, Initial residual = 0.00433935130145, Final residual = 1.51085917109e-14, No Iterations 1
Min/max T:1054.05482622 6338.15550763
ExecutionTime = 638 s  ClockTime = 639 s

Courant Number max: 0.386094136119
Region: solid Diffusion Number mean: 7.95881539575e-07 max: 8.74618219429e-05
deltaT = 0.000255878117071
Time = 0.0137691


Solving for fluid region fluid
MULES: Solving for alpha.gas
MULES: Solving for alpha.gas
MULES: Solving for alpha.gas
alpha.gas volume fraction = 0.937255076106  Min(alpha1) = -7.27218551617e-20  Max(alpha1) = 1
Constructing face momentum equations
Tf.gasAndLiquid: min = 300, mean = 385.004064355, max = 709.828579558
wDmdt.gasAndLiquid: min = 0, mean = 0.0114881446334, max = 1.60954163672, integral = 13.2924050358
DILUPBiCGStab:  Solving for h.gas, Initial residual = 0.730426800727, Final residual = 0.000638768312546, No Iterations 3
#0  Foam::error::printStack(Foam::Ostream&) at ??:?
#1  Foam::sigFpe::sigHandler(int) at ??:?
#2  ? in /lib/x86_64-linux-gnu/libpthread.so.0
#3  Foam::DILUPreconditioner::calcReciprocalD(Foam::Field<double>&, Foam::lduMatrix const&) at ??:?
#4  Foam::DILUPreconditioner::DILUPreconditioner(Foam::lduMatrix::solver const&, Foam::dictionary const&) at ??:?
#5  Foam::lduMatrix::preconditioner::addasymMatrixConstructorToTable<Foam::DILUPreconditioner>::New(Foam::lduMatrix::solver const&, Foam::dictionary const&) at ??:?
#6  Foam::lduMatrix::preconditioner::New(Foam::lduMatrix::solver const&, Foam::dictionary const&) at ??:?
#7  Foam::PBiCGStab::scalarSolve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const at ??:?
#8  Foam::PBiCGStab::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const at ??:?
#9  Foam::fvMatrix<double>::solveSegregated(Foam::dictionary const&) at ??:?
#10  Foam::fvMatrix<double>::solveSegregatedOrCoupled(Foam::dictionary const&) at ??:?
#11  Foam::fvMesh::solve(Foam::fvMatrix<double>&, Foam::dictionary const&) const at ??:?
#12  ? in /usr/lib/openfoam/openfoam1912/platforms/linux64GccDPInt32Opt/bin/chtMultiRegionTwoPhaseEulerFoam
#13  __libc_start_main in /lib/x86_64-linux-gnu/libc.so.6
#14  ? in /usr/lib/openfoam/openfoam1912/platforms/linux64GccDPInt32Opt/bin/chtMultiRegionTwoPhaseEulerFoam

From what I can understand the errors are clearly related to mesh in some way, but I am not sure how. Obviously, there is division by zero, and it could mean that the non-orthogonal faces are being problematic. But again, I am not sure and I need help to understand what this error is and some guidance if possible on how to solve it.


Any help is appreciated. Thank you.