[justeyong]

Hi there,

I have a simple geometry, which is a vertical tube. I know the inlet velocity and , and the pressure at outlet.

The turbulent model is standard k-epsilon. I set the inlet as velocity inlet with values of U, P, k, and epsilon.

However, when I set the outlet boundary condition, Pressure Outlet, the only thing I know is the pressure.

My question is how to (or do I need to) set the backflow turbulent k and backflow turbulent epsilon?

[valio]

Hi,

Set the same values of k and e for your pressure outlet condition.

You can launch your computation, save results and launch a computation with other values of k and e and see the influence, but I think it does not really matter.

Valio

[Far]

Originally Posted by justeyong

Hi there,

I have a simple geometry, which is a vertical tube. I know the inlet velocity and , and the pressure at outlet.

The turbulent model is standard k-epsilon. I set the inlet as velocity inlet with values of U, P, k, and epsilon.

However, when I set the outlet boundary condition, Pressure Outlet, the only thing I know is the pressure.

My question is how to (or do I need to) set the backflow turbulent k and backflow turbulent epsilon?

These values are used only when there is reverse flow I guess. Otherwise only pressure is required at outlet.

[justeyong]

Originally Posted by valio

Hi,

Set the same values of k and e for your pressure outlet condition.

You can launch your computation, save results and launch a computation with other values of k and e and see the influence, but I think it does not really matter.

Valio

Originally Posted by Far

These values are used only when there is reverse flow I guess. Otherwise only pressure is required at outlet.

Thanks very much!