Max residuals are far from poor quality cells

April 6, 2006, 07:40

Hello to everyone!

I have a hardly conveging task. Suspect cell with low internal angle. I cannot fully avoid them, but their number is negligible among perfect other cells. Remarkably, the regions of maximum residuals are at a long distance from those poor-quality cells.

QUESTION: May I therefore conclude those cells are NOT the reason of my difficult covergence?

Thank you.

April 6, 2006, 19:00

Hi,

Check that the region of maximum residual is not simply convected from the region of poor mesh quality, but if not then yes, your conclusion sounds reasonable.

regards, Glenn

April 6, 2006, 21:58

Yes, Glenn, I did checked and re-checked it: the regions are 3D-space-separated; only one small piece of residual isosurface is located near (upstream) to the low-angle one, but is not overlapping and its shape is different from the low-angle isosurface piece.

Furthemore, the largest piece of (the highest) residual isosurface is located in the (central) area, where the grid if ~0.7-times finer than that in other areas.

Thank you for your help and very best regards.

Steven

April 6, 2006, 07:40	Max residuals are far from poor quality cells	#1
Steven Guest Posts: n/a	Hello to everyone! I have a hardly conveging task. Suspect cell with low internal angle. I cannot fully avoid them, but their number is negligible among perfect other cells. Remarkably, the regions of maximum residuals are at a long distance from those poor-quality cells. QUESTION: May I therefore conclude those cells are NOT the reason of my difficult covergence? Thank you.

April 6, 2006, 19:00	Re: Max residuals are far from poor quality cells	#2
Glenn Horrocks Guest Posts: n/a	Hi, Check that the region of maximum residual is not simply convected from the region of poor mesh quality, but if not then yes, your conclusion sounds reasonable. regards, Glenn

April 6, 2006, 21:58	Re: Max residuals are far from poor quality cells	#3
Steven Guest Posts: n/a	Yes, Glenn, I did checked and re-checked it: the regions are 3D-space-separated; only one small piece of residual isosurface is located near (upstream) to the low-angle one, but is not overlapping and its shape is different from the low-angle isosurface piece. Furthemore, the largest piece of (the highest) residual isosurface is located in the (central) area, where the grid if ~0.7-times finer than that in other areas. Thank you for your help and very best regards. Steven

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