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Sastry February 21, 2007 00:30

reversed flow
 
hai friends,i am having only one proublem in my solution, i am getting reversed flow during the iterations, due to this my inlet pressuere is increasing that the value given,

how can reduce the reversed flow during the iterations inlet total pre= oulet static pre --> no recersed flow inlet total pre< outlet statis pre --> reversed flow coming but my condition is ps2/p01>3.5

please help any thing what u know in this regard


Pratik Mehta March 1, 2007 07:40

Re: reversed flow
 
set turbulence intensity at the pressure outlet very low , this should solve it


Sangeeta March 7, 2007 09:20

Re: reversed flow
 
I wanted to knw whether i should continue iterations even if it says reverse flows. will this iteration converge even if at some places there are reversed flows.

or i should give change the boundary conditions as soon as i get reversed flows while iterating.

Plz Help. Thanks in advance

ravindra March 9, 2007 05:21

Re: reversed flow
 
hi solution converges if the reversed flow comes at some places in the domain. when i simulated my problem, if reversed flow occurs at some places, my problem solution converged for residuals of e-6 and e-8. but you should have some validation for your solution, to decide whether converged solution is correct or not.

compare with ( some correlation) it , if the results are with in 5% error, u can take the solution.

hope this helps.


Sastry March 22, 2007 01:18

Re: reversed flow
 
ok some times reversed flow during the iterarions, will give the bad results,for some proublems like compressor starting the reversed flow during iteration is an indication of surging, try to change the bounadary condyions to avoid reversed flow

ok?

Sangeeta March 22, 2007 09:05

Re: reversed flow
 
Thanks


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