mathematical meaning of linear solver overflow

pamstad · October 7, 2019, 02:05

Hello everybody,

I have the following questions:

When looking at an outfile of a CFX simulation, there is one column which says "Linear Solution" and then for each Momentum equation (U, V, ..) there is a number and "OK" or "F". What is the theory behind this number? How does it get computed? Any good reference or textbook? (Nothing found in the Ansys guide)
What happens mathematically when a linear solver overflow occurs?

These are probably questions that are not answered in two or three lines of text, therefore textbook with passages are much appreciated, because I have found anything good yet.

Thanks and have a nice day!

Opaque · October 7, 2019, 08:29

You can find the answer to your question in the documentation. Check the section

CFX-Solver Managers User's Guide/Solver Files/Files Generated by CFX Solver/CFX Solver Output File/Convergence History

pamstad · October 8, 2019, 00:54

Once again Opaque, thank you for your answer and have a nice day!

October 7, 2019, 02:05	mathematical meaning of linear solver overflow	#1
pamstad Member Join Date: Sep 2019 Posts: 33 Rep Power: 6	Hello everybody, I have the following questions: When looking at an outfile of a CFX simulation, there is one column which says "Linear Solution" and then for each Momentum equation (U, V, ..) there is a number and "OK" or "F". What is the theory behind this number? How does it get computed? Any good reference or textbook? (Nothing found in the Ansys guide) What happens mathematically when a linear solver overflow occurs? These are probably questions that are not answered in two or three lines of text, therefore textbook with passages are much appreciated, because I have found anything good yet. Thanks and have a nice day!

October 7, 2019, 08:29		#2
Opaque Senior Member Join Date: Jun 2009 Posts: 1,804 Rep Power: 32	You can find the answer to your question in the documentation. Check the section CFX-Solver Managers User's Guide/Solver Files/Files Generated by CFX Solver/CFX Solver Output File/Convergence History Ashkan Kashani likes this.

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October 8, 2019, 00:54		#3
pamstad Member Join Date: Sep 2019 Posts: 33 Rep Power: 6	Once again Opaque, thank you for your answer and have a nice day!