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KEpsilon model incorrect result

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Old   August 26, 2022, 06:37
Default KEpsilon model incorrect result
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Hello
I am trying to simulate a realizableKE model.
Geometry: 0.006x0.009mm rectangle.
BC: top bottom - walls; sides - symmetry; left - inlet; right - outlet

I calculated the velocity for the Reynolds numbers 500, 2000, 5000, and 9000 to be [0.04959, 0.19837, 0.4959, 0.8926] m/s with the hydraulic diameter being the distance between the top and bottom walls. (I consider this case as a parallel plate as I am using symmetry on either side)

The simulation ran perfectly fine for RE500 and RE2000 but the 5000 Reynolds number is causing problems. I will attach the case setup for reference.

Though, I defined no-slip condition for top bottom walls velocity is unevenly spread on the walls which I have no clue why.
Screenshot 2022-08-23 115955.jpg

Simulation converged to 1e-4
Code:
Time = 3000

smoothSolver:  Solving for Ux, Initial residual = 0.000166362, Final residual = 1.08171e-06, No Iterations 2
smoothSolver:  Solving for Uy, Initial residual = 9.70676e-07, Final residual = 9.70676e-07, No Iterations 0
smoothSolver:  Solving for Uz, Initial residual = 1.86604e-05, Final residual = 1.41014e-07, No Iterations 2
GAMG:  Solving for p, Initial residual = 0.000271834, Final residual = 1.46852e-06, No Iterations 2
GAMG:  Solving for p, Initial residual = 1.46851e-06, Final residual = 4.37859e-07, No Iterations 1
GAMG:  Solving for p, Initial residual = 4.3786e-07, Final residual = 4.3786e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 4.3786e-07, Final residual = 4.3786e-07, No Iterations 0
time step continuity errors : sum local = 2.11366e-07, global = 6.86507e-09, cumulative = 0.000122676
smoothSolver:  Solving for epsilon, Initial residual = 3.00512e-06, Final residual = 4.96645e-08, No Iterations 2
bounding epsilon, min: -0.00358805 max: 3.25773 average: 0.12346
smoothSolver:  Solving for k, Initial residual = 5.60576e-07, Final residual = 5.60576e-07, No Iterations 0
ExecutionTime = 9182.55 s  ClockTime = 9221 s
If anyone has any idea why this is happening please help

Best regards,

Case: flowDevelop_5000.zip
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kepsilon, openfoam, turbulance

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