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Deadly August 29, 2002 04:59

Plz help in using "Patching"..
DEar all,

I currently iterated a model using a velocity of 5m/s and saved the iterated case and data.. I need to try another case, now with 10 m/s but using the case and data from the previously iterated 5m/s model.(for faster convergence) To do tht, i read the case and data file of the 5m/s model and went to patch to increase the velocity to 10 m/s. Though, the iteration started from the previously converged data, the residuals plot showed a vertical line drawn after the residuals plot for the 5m/s converged data...and the residuals for the 10m/s model started from the vertical line onwards.. It looked like as though the solver wasnt using the results of the previously converged data..and was iterating all over again for the 10m/s model.. CAn someone help me confirm whether wht is going on is normal?


david August 29, 2002 22:16

Re: Plz help in using "Patching"..
Sorry I am confused. Please clarify:

Did you patch the velocity to 10m/s and left the inlet velocity to 5m/s ?

The residuals may jump up, but should calm (come) down shortly !!


Deadly August 29, 2002 22:47

Re: Plz help in using "Patching"..
Initially when i was running the 5m/s model, i initialised from the velocity-inlet(which i had created in Gambit) Then i was asked to run a 10m/s using results calacuated from the 5m/s model.. Therefore, i read the case and data file from the alredy iterated 5m/s model and patched the velocity(z velocity) to 10m/s.. However, when i stopped the iterations todae to check if the velocity inlet was indeed 10m/s(by doing a surface integral on the inlet), i found tht it is still 5m/s!.. How do i solve this problem? Plz do help..cos me running out of time ready.. Your help is greatly appreciated..


Deadly August 30, 2002 01:20

Re: Plz help in using "Patching"..
Just to be precise..Once i patched the velocity to 10m/s, i just clicked iterate form the last set of converged solution(whish is the 5m/s)... so the current case started iterating from where last case stopped..

DO i have to initialise after patching?..if i do tht, i get the ,message"Discard previous data"?.. I need the previous


pp August 30, 2002 08:36

Re: Plz help in using "Patching"..

Just change 5 to 10m/s in your VI panel and iterate. You do not need to patch domain.



Deadly August 30, 2002 08:47

Re: Plz help in using "Patching"..
Whts does VI panel mean? If i do this, will it start iterating from the 5m/s iterated results? still quite new to fluent.. thnx..


pp August 30, 2002 16:15

Re: Plz help in using "Patching"..
Velocity Inlet panel (or whateveer you have Mass flow Inlet etc.).

Yes it will start from 5m/s calcilated fields.

1.Set 5m/s

2.Iterate - convergence

3.Set 10m/s

4.Just Iterate

BR, pp

Deadly August 30, 2002 22:55

Re: Plz help in using "Patching"..
sorry to bother again.. From your reply, i gather i dun need to click initialise again when i change the boundary conditions to 10m/s right?

Meaning, i dun even need to use patch at all?

pp August 31, 2002 05:41

Re: Plz help in using "Patching"..
No you do not need to initialize any more.

Deadly September 1, 2002 23:48

Re: Plz help in using "Patching"..
okie..thnx for ya help...

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