[itsme_kit]

I wonder why we sometimes can apply steady state in the modelling of turbulent flow

Many thanks

[agd]

Because in such cases (Reynolds-averaged Navier Stokes) you are solving for the mean quantities from the Reynolds averaging. These quantities are considered to be steady, since any time dependency has been averaged out.

[leflix]

Originally Posted by itsme_kit

I wonder why we sometimes can apply steady state in the modelling of turbulent flow

Many thanks

It's not a silly question ! It's very clever,
it is indeed paradoxical as turbullent flow are strongly unsteady !!

agd gave the right answer!!

[ztdep]

Originally Posted by itsme_kit

I wonder why we sometimes can apply steady state in the modelling of turbulent flow

Many thanks

some time , when the boundary is moving , then we use the unsteay governing equations.