[nukecrafts]

Hello FOAMers,

I've searched the forum but couldn't find direct answer (for now).

I'm trying to perform channel flow validation based on Channel395 tutorial case. I receive consistent results in case of velocity profile and turbulent kinetic energy.

There is one issue,

Once I obtain wall shear stress value by postprocessing to evaluate Utau and the rest, I perform averaging for walls (at the top and bottom) first and that use it for calculations. I noticed that wall shear stress (average) is changing significantly if I choose different time step.

According to my observations Retau becomes something around 400 and 370 (there is something odd)

How should I evaluate wall shear stress? If I perform sampling for ex. for 100 different time steps same thing happens.

I read that one can use pressure gradient on log file in another thread, Is anyone did this before?

LES of turbulent channel flows