reversed flow in cyclone
 

Does anyone know what cause the reversed flow at the top and bottome outlet of cyclone? How to let it go in the simulation? How to select parameters to let the solution converge? What is the transient solver? Where to find it in Fluent?

Thanks. Tom

Re: reversed flow in cyclone
 

what boundary condition did you give the outlet of cyclone? maybe reversed flow is the physical nature. Does transient solver refer to unsteady flow? If do, it is in DEFINE-MODELS-SOLVER Can you state your model in detail?

Re: reversed flow in cyclone
 

Hi, Lcw, Thank you for the reply. I try to model an ordinary cyclone. It has one tangential inlet and two outlet, top and bottom. The boundary conditions for two outlets are pressure-outlet, and for inlet is velocity. Will reverse flow exist in the final converged solution?

I am not sure about the transient solver too. I saw it in one of the previous message about boundary condition set up and solution convergence. It also mentioned some time scale. I do not know where to define it.

Tom

Re: reversed flow in cyclone
 

The flow in cyclone is transient(unsteady) because of PVC, I do not know the length of your cyclone outlet? Maybe reversed flow is the nature of flow in outlet, because the flow is still swirling in outlet. your mentioned some time scale, does it refer to time step? I think this should be determined by frequency of PVC.