CFD Online Discussion Forums - nan in potential foam in decomposed form

OK. So i solved the NaN issue with potentialFoam by choosing the simple method in decomposePar.
However when i tried to run pimpleFoam, i get NaNs on the first iterations.

Code:

PIMPLE: no residual control data found. Calculations will employ 2 corrector loops



Reading field p



Reading field U



Using the loglaw boundary condition

Reading/calculating face flux field phi



Selecting incompressible transport model Newtonian

Selecting turbulence model type LES

Selecting LES turbulence model dynamicKEqn

Selecting LES delta type cubeRootVol

bounding k, min: 0 max: 0.167 average: 0.167

dynamicKEqnCoeffs

{

    filter          simple;

    Ce              1.048;

}



No MRF models present



No finite volume options present





Starting time loop



fieldAverage fieldAverage1:

    Starting averaging at time 0



Reading surface description:

    nearWall



Courant Number mean: 2.78783e-05 max: 0.0216974

deltaT = 1.2e-08

Time = 1.2e-08



PIMPLE: iteration 1

smoothSolver:  Solving for Ux, Initial residual = nan, Final residual = nan, No Iterations 1000

smoothSolver:  Solving for Uy, Initial residual = nan, Final residual = nan, No Iterations 1000

smoothSolver:  Solving for Uz, Initial residual = nan, Final residual = nan, No Iterations 1000

I set prefpoint at the outlet. The case is just a simple wind tunnel experiment with a backward facing step. I am just not sure why I am getting nan on the first few iterations.