Outflow for suction pressure
 

Hi

In FLUENT can "outflow" be used, at the outlet, where the flow is fully developed and the vaccum pressure applied.

If air is being sucked (negative pressure at the outlet); is it fine to use "Outflow" BC or "pressure outlet" would be used instead? When I use "pressure outlet BC" I get reverse flow in 50 faces...Is it normal??

I am using cyclone and have a total cell size of about 0.4 Million.

Please assist

when there is back flow in outlet, you should use pressure outlet.