Use of ConsistentStrainSmagorinskyBGK model in nozzle3d

[sfraniatte]

Hello,

I tried to use the ConsistentStrainSmagorinskyBGK model but it does not work properly in the nozzle3d example. I tried with the last version (and some previous version of the 1.8.1 release) of OpenLB available on Gitlab (master branch) with one GPU. I have also the same problem with the tgv3d example and with the KrauseBGK model.

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[initialize] Version : 1.8r1
[initialize] Platform : CPU_SISD GPU_CUDA
[initialize] Parallel : None
[GPU_CUDA] Found 2 CUDA devices but only one can be used per MPI process.
[GPU_CUDA] Detected NVIDIA RTX A6000.
[GPU_CUDA] Detected NVIDIA GeForce RTX 3080 Ti.
[ThreadPool] Sucessfully initialized, numThreads=1
[Case]
[Case] — OpenLB Case Components —
[Case] names::NavierStokes = SuperLattice<double, olb::descriptors::D3Q27<> >
[Case]
[Case] — Parameters —
[Case] TURBULENCE_SIGMA = 0.1
[Case] TURBULENCE_N_TIME = 0.1
[Case] TURBULENCE_N_SEEDS = 50
[Case] TURBULENCE_INTENSITY = 0.05
[Case] INLET_CYLINDER_SIZE = [4 1]
[Case] BULK_MODEL = 4
[Case] PHYS_CHAR_VISCOSITY = 0.0002
[Case] RESOLUTION = 5
[Case] PHYS_DELTA_X = 0.2
[Case] DOMAIN_EXTENT = [60 11 11]
[Case] PHYS_CHAR_VELOCITY = 1
[Case] PHYS_CHAR_DENSITY = 1
[Case] LATTICE_RELAXATION_TIME = 0.500018
[Case] SMAGORINSKY = 0.15
[Case] OVERLAP = 3
[Case] MAX_PHYS_T = 150
[Case] PHYS_STAT_ITER_T = 0.1
[Case] PHYS_VTK_ITER_T = 1
[Case]
[prepareGeometry] Prepare Geometry …
[Directories] Directory ./tmp/ created.
[Directories] Directory ./tmp/imageData/ created.
[Directories] Directory ./tmp/imageData/data/ created.
[Directories] Directory ./tmp/vtkData/ created.
[Directories] Directory ./tmp/vtkData/data/ created.
[Directories] Directory ./tmp/gnuplotData/ created.
[Directories] Directory ./tmp/gnuplotData/data/ created.
[Directories] Directory ./tmp/introspectionData/ created.
[SuperGeometry3D] cleaned 220096 outer boundary voxel(s)
[SuperGeometry3D] cleaned 0 inner boundary voxel(s)
[SuperGeometryStatistics3D] updated
[SuperGeometry3D] the model is correct!
[CuboidDecomposition] — Cuboid Structure Statistics —
[CuboidDecomposition] Number of Cuboids: 1
[CuboidDecomposition] Delta : 0.2
[CuboidDecomposition] Ratio (min): 0.186047
[CuboidDecomposition] (max): 5.375
[CuboidDecomposition] Nodes (min): 943936
[CuboidDecomposition] (max): 943936
[CuboidDecomposition] Weight (min): 943936
[CuboidDecomposition] (max): 943936
[CuboidDecomposition] ———————————
[SuperGeometryStatistics3D] materialNumber=0; count=220096; minPhysR=(0,0,0); maxPhysR=(60,11,11)
[SuperGeometryStatistics3D] materialNumber=1; count=656532; minPhysR=(0.4,0.2,0.2); maxPhysR=(59.6,10.8,10.8)
[SuperGeometryStatistics3D] materialNumber=2; count=64880; minPhysR=(0.2,0,0); maxPhysR=(59.8,11,11)
[SuperGeometryStatistics3D] materialNumber=3; count=80; minPhysR=(0.2,4.6,4.6); maxPhysR=(0.2,6.4,6.4)
[SuperGeometryStatistics3D] materialNumber=4; count=2348; minPhysR=(59.8,0.2,0.2); maxPhysR=(59.8,10.8,10.8)
[SuperGeometryStatistics3D] countTotal[1e6]=0.943936
[prepareGeometry] Prepare Geometry … OK
[prepareLattice] Prepare Lattice …
[UnitConverter] —————– UnitConverter information —————–
[UnitConverter] — Parameters:
[UnitConverter] Resolution: N= 5
[UnitConverter] Lattice velocity: latticeU= 0.006
[UnitConverter] Lattice relaxation frequency: omega= 1.99993
[UnitConverter] Lattice relaxation time: tau= 0.500018
[UnitConverter] Characteristical length(m): charL= 1
[UnitConverter] Characteristical speed(m/s): charU= 1
[UnitConverter] Phys. kinematic viscosity(m^2/s): charNu= 0.0002
[UnitConverter] Phys. density(kg/m^d): charRho= 1
[UnitConverter] Characteristical pressure(N/m^2): charPressure= 0
[UnitConverter] Mach number: machNumber= 0.0103923
[UnitConverter] Reynolds number: reynoldsNumber= 5000
[UnitConverter] Knudsen number: knudsenNumber= 2.07846e-06
[UnitConverter] Characteristical CFL number: charCFLnumber= 0.006
[UnitConverter]
[UnitConverter] — Conversion factors:
[UnitConverter] Voxel length(m): physDeltaX= 0.2
[UnitConverter] Time step(s): physDeltaT= 0.0012
[UnitConverter] Velocity factor(m/s): physVelocity= 166.667
[UnitConverter] Density factor(kg/m^3): physDensity= 1
[UnitConverter] Mass factor(kg): physMass= 0.008
[UnitConverter] Viscosity factor(m^2/s): physViscosity= 33.3333
[UnitConverter] Force factor(N): physForce= 1111.11
[UnitConverter] Pressure factor(N/m^2): physPressure= 27777.8
[UnitConverter] ————————————————————-
[UnitConverter] WARNING:
[UnitConverter] Potentially UNSTABLE combination of relaxation time (tau=0.500018)
[UnitConverter] and characteristical CFL number (lattice velocity) charCFLnumber=0.006!
[UnitConverter] Potentially maximum characteristical CFL number (maxCharCFLnumber=0.000144)
[UnitConverter] Actual characteristical CFL number (charCFLnumber=0.006) > 0.000144
[UnitConverter] Please reduce the the cell size or the time step size!
[UnitConverter] We recommend to use the cell size of 0.0048 m and the time step size of 2.88e-05 s.
[UnitConverter] ————————————————————-
[prepareLattice] Prepare Lattice … OK
[VortexMethod] inletArea=6.4
[Timer] step=0; percent=0; passedTime=0.261; remTime=32624.7; MLUPs=0
[LatticeStatistics] step=0; physT=0; maxCFL=1.49167e-154; avgEnergy=0; avgRho=1
[Timer] step=83; percent=0.0664; passedTime=4.527; remTime=6813.24; MLUPs=14.0832
[LatticeStatistics] step=83; physT=0.0996; maxCFL=1.49167e-154; avgEnergy=-nan; avgRho=-nan

[sfraniatte]

I forgot to say thank you again for all this work. It is a great tool !

Best regards,

Sylvain

[Author]

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