plz help:"outflow" BC problem

subhransu

hello, Am trying to find the HTCs in circular jet impingement cooling of air on a metal plate. The inlet is thru a nozzle of dia 1" and the outflow is thru the curved area of cylinder dia 10" and height 2". The outlet boundry condn is "OUTFLOW". It's creating a lot of convergence issues bcoz there is back flow, actually there is recirculation, is the reverse flow because of that, will it be solved if i increase my domain.

_____________________| ! |_______________________

<----.................................................. .................................------->

_______________________________________________ <--the cooled plate

Another q is that can i use two symetric BC to model a circular section of 30 deg like this" <)" hope you got it