High Recirculation perpendicular to outlet
 

Dear Pals,

If there is a recirculation which is perpendicular and propagating towards outlet (Like Swirl flow towards outlet) convergence is bit difficult to achieve. what cfx people suggesting is 1) we can extend the outlet 2)we can specify a opening boundary condition. but for the flows like the one i have specified even if you try these attempts wont help much. what else can be done to achieve convergence or to get a valid solution ?????

Bcoz of the oscillation of residuals there will be ups and downs in imbalances, even any no iterations you run.

Re: High Recirculation perpendicular to outlet
 

If extending the outlet doesn't help on the lack of convergence, many other things could be the reason for lack of convergence. Grid quality could be one thing, or the flow could just be transient by nature. I would extend the domain avoiding recirculation at the boundaries and solve it transient. Also monitoring global variables is worth an effort. -Dr. Flow Squad http://tinyurl.com/2gkjh8