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abel April 24, 2005 11:51

reversed flow???
Hello! I am looking for the meaning of "reversed flow" message, it appears(when iterating) during the fluent calculation, is it related to the inlet(operating) conditions? does it affect the solution precision? numerical or physical sens?


Harish April 24, 2005 16:46

Re: reversed flow???
Reversed flow implies a boundary layer separation , the flow velocity changes direction. In some calculations like say the flow past a cylinder the flow is reversed.It occurs when the pressure gradient changes sign.


Mehdi Ghoddosy April 25, 2005 01:48

Re: reversed flow???
Dear Abel: FLuent assumes developed flow for some types of inbuilt boundary conditions such as outflow. Hence you should place your boundary in a place that flow is fully developed and no reverse flow exits, otherwise the mass consevation equation would not satisfy and solution convergence fails. The reverse flow alert would be shown if you have any type of reverse flow such as boudary layer separation befor boundary. Regards Mehdi Ghoddosy

kiran April 29, 2005 04:54

Re: reversed flow???
hi mehdi for compressibleflow, outflow condition is not valid,in such cases pressure outlet is works. but in nozzle flow for getting exact mach numer we should specify pressure at uhave any idea about convergence of species transportation problem in nozzel?

regards kiran

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