InterFoam very small timestep

unoder

Hi,

Could anyone please have a look at this case and tell me if it's normal for the timestep to be so small - and perhaps it's getting smaller yet (1E-7 sec)? I think there's something wrong here, perhaps boundary/initial conditions?

nCorrectors is 3 - the geometry consists of hex elements. checkMesh doesn't complain about any "severe errors" - a little output (although I don't know what exactly it means):

Checking geometry...
Boundary openness in x-direction = -1.75251e-18
Boundary openness in y-direction = 5.40229e-17
Boundary openness in z-direction = 4.90284e-17
Boundary closed (OK).
Max cell openness = 8.47039e-22 Max aspect ratio = 1.00033. All cells OK.

Minumum face area = 2.12057e-06. Maximum face area = 2.35618e-06. Face area magnitudes OK.

Min volume = 3.19848e-09. Max volume = 3.51656e-09. Total volume = 0.000134475. Cell volumes OK.

Mesh non-orthogonality Max: 0.106083 average: 0.00296587
Non-orthogonality check OK.

Face pyramids OK.

Max skewness = 0.181423 percent. Face skewness OK.

Minumum edge length = 0.00141371. Maximum edge length = 0.00157079.

All angles in faces are convex or less than 10 degrees concave.


hexbody_rund_meshed.tgz

I also had this problem with the timestep when I tried to do a calculation with tet-elements, so I'm pretty disappointed if this won't work when I've switched to hex-elements, if you understand :-)