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November 11, 2015, 16:17 |
problem with convergence
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#1 |
New Member
Reza Rohani
Join Date: Apr 2015
Posts: 7
Rep Power: 11 |
I'm new to fluent. I want to simulate a rectangular nozzle in 2D. Wondering when I use mesh NO.1 it converges properly after 17500 iterations, but in mesh NO.2 when I refine it near throats and cavities even without add boundary layer, residuals oscillate and it doesn't converge after 270k iterations.
I really appreciate it if anyone could help, Thanks in advance.
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Knowledge is power and it can command obedience. Remember that knowledge is a ruler and wealth is its subject. The Peak of Eloquence, Saying 146 |
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November 12, 2015, 01:49 |
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#2 |
Senior Member
Lucky
Join Date: Apr 2011
Location: Orlando, FL USA
Posts: 5,760
Rep Power: 66 |
What do your mesh metrics say?
It looks like there's too rapid area/volume change in the regions where you refined the grid, especially at the outlet. Keep your volume change <33% or so between adjacent cells. But also check your skewness. It's hard to tell if the skewness was worse the refined grid in the picture. |
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November 12, 2015, 18:05 |
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#3 | |
New Member
Reza Rohani
Join Date: Apr 2015
Posts: 7
Rep Power: 11 |
Quote:
__________________
Knowledge is power and it can command obedience. Remember that knowledge is a ruler and wealth is its subject. The Peak of Eloquence, Saying 146 |
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Tags |
convergence, fluent, nozzle, nozzle simulation, oscillating residuals |
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