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-   -   Reversed Flow Error(pressure correction limited...) (http://www.cfd-online.com/Forums/star-ccm/99975-reversed-flow-error-pressure-correction-limited.html)

fshak92 April 17, 2012 10:08

Reversed Flow Error(pressure correction limited...)
 
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I have a body surrounded by a block(Air).
I considered LeftWall of the block as 'velocity inlet' and Right one as 'pressure outlet' to have a flow with a constant temperature over my heated body to consider the influence of the air on my body.
Also i used the default value of the inlet and outlet walls.

Using both Coupled and Segregated Solver give me the warning about pressure correction limited on many faces and reversed flow.


I appreciate if anyone has any idea or suggestion.

hyderkhan74 April 17, 2012 10:55

Hi
If you use buoyancy with Boussinesq model ,then double check for the reference temperature (which is most be near the domain temperature ).

fshak92 April 17, 2012 11:05

Quote:

Originally Posted by hyderkhan74 (Post 355182)
Hi
If you use buoyancy with Boussinesq model ,then double check for the reference temperature (which is most be near the domain temperature ).

Thank you for your reply.
I did not use the boussineq model.
But i ignored the 'gravity' and now it works better.(I get the reversed flow error after the first iterations just for 6 or 7 faces now)
Do you know the influence of gravity in my case? can it be ignored?

Many thanks in advance.

hyderkhan74 April 17, 2012 11:54

Hi
If you have an air in touch with hot surface than you have a change in the density, and this will generate a buoyancy. If you ignored the gravity it will solve the issue of reversed flow, but it will not be a realistic flow.

arjun April 17, 2012 18:39

Quote:

Originally Posted by omid88 (Post 355170)
I have a body surrounded by a block(Air).
I considered LeftWall of the block as 'velocity inlet' and Right one as 'pressure outlet' to have a flow with a constant temperature over my heated body to consider the influence of the air on my body.
Also i used the default value of the inlet and outlet walls.

Using both Coupled and Segregated Solver give me the warning about pressure correction limited on many faces and reversed flow.


I appreciate if anyone has any idea or suggestion.


It probably means you need to refine the mesh. If you are seeing reverse flow then it could mean your outlet is too close. If possible extend it.


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