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simpleFOAM (RANS) - internal pipe flow - 'k'

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Old   April 24, 2018, 14:41
Default simpleFOAM (RANS) - internal pipe flow - 'k'
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gu1
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Guilherme
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Hello,

First, I'm using OpenFOAM 5.0 (RANS - realizebleKE):

Re=5300 (R = 0,00635 - L=4D)

BC:
Quote:
pipe_wall

epsilon
internalField uniform 0.00952;
{
type epsilonWallFunction;
value uniform 0.00952;
}

k
internalField uniform 4.5e-3;
{
type fixedValue;
value uniform 1e-15;
}
OBS: Using kLowReWallFunction I'm having the same problem.

nut
internalField uniform 0;
{
type calculated;
value uniform 0;
}

p
internalField uniform 0;
{
type zeroGradient;
}

U
internalField uniform (1 0 0);
{
type fixedValue;
value uniform (0 0 0);
}

cyclic domain

log:

...

Time = 1500

smoothSolver: Solving for Ux, Initial residual = 8.14155e-05, Final residual = 7.41441e-06, No Iterations 3
smoothSolver: Solving for Uy, Initial residual = 7.04818e-05, Final residual = 3.22128e-06, No Iterations 3
smoothSolver: Solving for Uz, Initial residual = 5.7334e-05, Final residual = 3.25325e-06, No Iterations 3
Pressure gradient source: uncorrected Ubar = 0.999999, pressure gradient = 1.05028
GAMG: Solving for p, Initial residual = 0.000159464, Final residual = 1.44095e-06, No Iterations 2
time step continuity errors : sum local = 1.32913e-07, global = -2.98883e-10, cumulative = -4.11386e-07
Pressure gradient source: uncorrected Ubar = 1, pressure gradient = 1.04501
smoothSolver: Solving for epsilon, Initial residual = 5.50983e-05, Final residual = 4.04455e-06, No Iterations 2
smoothSolver: Solving for k, Initial residual = 5.71171e-08, Final residual = 5.71171e-08, No Iterations 0
ExecutionTime = 1851.33 s ClockTime = 2205 s

yPlus yPlus write:
writing object yPlus
patch pipe y+ : min = 0.973688, max = 1.13078, average = 1.06766
I started a simulation using the realizableKE model in order to compare it to my kOmegaSST simulation (whose convergence). I noticed that when starting the simulation, the values of 'k' assume the following pattern (attached image), could someone advise me on what to do in relation?
Attached Images
File Type: jpg OF.jpg (42.7 KB, 25 views)
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Old   May 15, 2018, 08:17
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  #2
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JD
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So, I have a question about your question. Given that you're using wallFunctions, wouldn't you want your y+ to be between 30 and 300?
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openfoam, rans, realizableke, turbulence kinetic energy


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