Inlet value

Nkl · December 24, 2013, 12:07

Hi everyone,

I have run more than 6000 iterations when I realized that the value of mass flow rate that I have putted at the inlet of my system was one order of magnitude lower of the one I should have put. Do I have to clear all the generated data and run the solution again? All the results I have generated until now are not valid for my purpose?

Thank you in advance...

ghorrocks · December 25, 2013, 04:30

You can use your current simulation as an initial condition for the corrected run.

And if you need 6000 iterations for convergence then something is probably wrong. CFX should not take that long to converge expect in rare cases.

Nkl · December 25, 2013, 11:11

I am performing a 3D simulation on a huge solar chimney power plant, the chimney is 1 km high and the collector has a diameter of 600 m. I was told that convergence is not reached because it is not a steady state (even if I've putted steady state in the setup) and is oscillating around a certain value. Here I allege a screenshot. Thanks for the help!

ghorrocks · December 25, 2013, 23:08

There is an FAQ on this exact issue: http://www.cfd-online.com/Wiki/Ansys...gence_criteria

Nkl · December 26, 2013, 07:26

Thank you!

December 24, 2013, 12:07	Inlet value	#1
Nkl Member Nikola Join Date: Sep 2013 Location: Madrid, Spain Posts: 60 Rep Power: 12	Hi everyone, I have run more than 6000 iterations when I realized that the value of mass flow rate that I have putted at the inlet of my system was one order of magnitude lower of the one I should have put. Do I have to clear all the generated data and run the solution again? All the results I have generated until now are not valid for my purpose? Thank you in advance...

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
setting the correct format of nonuniform List<vector> for inlet in 0 Folder	cfdonline2mohsen	OpenFOAM Running, Solving & CFD	8	July 18, 2019 08:03
multiple inlet as one inlet	amin_gls	CFX	2	October 2, 2013 08:59
velocity inlet and ideal gas simultaneously-what's wrong?	preetam69	FLUENT	0	September 28, 2013 04:51
Inlet Velocity in CFX	aeroman	CFX	12	August 6, 2009 18:42
Diffusion component at inlet	Balaji	FLUENT	2	August 8, 2005 07:37

December 25, 2013, 04:30		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	You can use your current simulation as an initial condition for the corrected run. And if you need 6000 iterations for convergence then something is probably wrong. CFX should not take that long to converge expect in rare cases.

December 25, 2013, 23:08		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	There is an FAQ on this exact issue: http://www.cfd-online.com/Wiki/Ansys...gence_criteria

December 26, 2013, 07:26		#5
Nkl Member Nikola Join Date: Sep 2013 Location: Madrid, Spain Posts: 60 Rep Power: 12	Thank you!