[CiccioPasticcio]

Hi all,
I am running a simulation for external aerodynamics with simpleFoam. I am quite confident with my "standard" setup, never had big troubles. But there is one case (same bc, just different geometry) where I have some problem. The solution doesn't look to bad, but I have high residuals mainly for pressure. Can this suggest that there is a problem somewhere?
The residuals go incredibly low in the first 50-100 iteration, pressure to 0.0005 (usually these simulation converged at 0.008) but then suddenly start increasing. I am trying also with first order and 1 nonOrthoCorrector but it looks similar. I'll paste the output and some setting:

without corrector:

smoothSolver: Solving for Ux, Initial residual = 9.53135923113133e-05, Final residual = 6.40125609233725e-06, No Iterations 3
smoothSolver: Solving for Uy, Initial residual = 0.00583292437866579, Final residual = 0.000408635173001429, No Iterations 3
smoothSolver: Solving for Uz, Initial residual = 0.00107172584371381, Final residual = 7.33804021586605e-05, No Iterations 3
GAMG: Solving for p, Initial residual = 0.370892890676336, Final residual = 0.00805233261805146, No Iterations 2
time step continuity errors : sum local = 8.93727966506124e-05, global = -7.38809614603939e-07, cumulative = 0.00600977288580794
smoothSolver: Solving for omega, Initial residual = 5.71563590189836e-05, Final residual = 5.20189909513911e-06, No Iterations 4
smoothSolver: Solving for k, Initial residual = 0.00296034798651617, Final residual = 0.000165450839972275, No Iterations 3
ExecutionTime = 68868.42 s ClockTime = 69068 s

with corrector:


Time = 1238

smoothSolver: Solving for Ux, Initial residual = 0.000235167399322179, Final residual = 1.49861216273521e-05, No Iterations 3
smoothSolver: Solving for Uy, Initial residual = 0.0167873770137804, Final residual = 0.00104310120382418, No Iterations 3
smoothSolver: Solving for Uz, Initial residual = 0.00393616314129379, Final residual = 0.000237925232432727, No Iterations 3
GAMG: Solving for p, Initial residual = 0.479556064779533, Final residual = 0.00355207736688959, No Iterations 3
GAMG: Solving for p, Initial residual = 0.171937712915105, Final residual = 0.00129806088756816, No Iterations 4
time step continuity errors : sum local = 7.17828577284389e-05, global = -6.80223237496025e-07, cumulative = 0.00594026418728066
smoothSolver: Solving for omega, Initial residual = 8.49925768943358e-05, Final residual = 5.65726497999539e-06, No Iterations 4
smoothSolver: Solving for k, Initial residual = 0.00579911848397957, Final residual = 0.000283318812986071, No Iterations 3
ExecutionTime = 69734.74 s ClockTime = 69934 s


Settings:


divSchemes

{
default Gauss linear;
//div(phi, U) Gauss linearUpwindV cellLimited Gauss linear 1;
//div(phi,U) Gauss linearUpwindV Gauss linear;
div(phi,U) Gauss upwind;
div(phi,Ualter) Gauss linearUpwindV cellMDLimited Gauss linear 1;
div(phi,k) Gauss upwind;
div(phi,kl) Gauss limitedLinear 1;
div(phi,epsilon) Gauss limitedLinear 1;
div(phi,omega) Gauss upwind;
div(phi,R) Gauss upwind;
div(R) Gauss linear;
div(phi,nuTilda) Gauss limitedLinear 1;
div((nuEff*dev(grad(U).T()))) Gauss linear;
}

SIMPLE
{
nNonOrthogonalCorrectors 1;
pressureImplicitPorousity false;
pRefCell 0;
pRefValue 0;
pdRefCell 0;
pdRefValue 0;
}

solvers
{
//p GAMG { agglomerator faceAreaPair ; mergeLevels 1 ; cacheAgglomeration true ; nCellsInCoarsestLevel 200 ; tolerance 1e-07 ; relTol 0.05 ; smoother GaussSeidel ; nPreSweeps 0 ; nPostSweeps 2 ; nFinestSweeps 2 ; };
p GAMG { agglomerator faceAreaPair ; mergeLevels 1 ; cacheAgglomeration true ; nCellsInCoarsestLevel 200 ; tolerance 1e-07 ; relTol 0.01 ; smoother GaussSeidel ; nPreSweeps 0 ; nPostSweeps 2 ; nFinestSweeps 2 ; };
U smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
k smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
kl smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
epsilon smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
R smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
nuTilda smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
omega smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
h smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
T smoothSolver { smoother GaussSeidel ; tolerance 1e-06 ; relTol 0.1 ; };
rho PCG { preconditioner DIC ; tolerance 0 ; relTol 0 ; };
}


relaxationFactors
{
p 0.2;
pd 0.3;
U 0.5;
k 0.5;
kl 0.7;
epsilon 0.7;
R 0.7;
nuTilda 0.7;
omega 0.7;
h 0.7;
rho 1;
}


I have tried different under relaxation but if didn't help.
I hope someone can help me or suggest somethings!


thanks in advance

Ciao!

Ciccio