[Other] what means information checkMesh give?

immortality · June 30, 2013, 13:04

Hi
what does mean boundary openness and Max cell openness?
is this mesh OK? aspect ratio till what value is acceptable?

Code:

Checking geometry...
    Overall domain bounding box (0 0 0) (0.069 0.004 0.003)
    Mesh (non-empty, non-wedge) directions (1 1 0)
    Mesh (non-empty) directions (1 1 0)
    All edges aligned with or perpendicular to non-empty directions.
    Boundary openness (-5.347430223e-18 -1.447816733e-16 -9.586797705e-16) OK.
    Max cell openness = 1.983242651e-16 OK.
    Max aspect ratio = 3.171630836 OK.
    Minimum face area = 3.888093411e-09. Maximum face area = 5.2674561e-07.  Face area magnitudes OK.
    Min volume = 1.166428023e-11. Max volume = 5.832140299e-11.  Total volume = 8.28e-07.  Cell volumes OK.
    Mesh non-orthogonality Max: 0 average: 0
    Non-orthogonality check OK.
    Face pyramids OK.
    Max skewness = 0.0002143106966 OK.
    Coupled point location match (average 0) OK.

akidess · July 1, 2013, 04:31

I believe openness is only a concern when doing CAD import. CAD geometries tend to be not perfect and can lead to unwanted gaps in your geometry/mesh on import. The values in your log file are good (close to zero).

immortality · July 1, 2013, 05:27

Hi Anton
thanks so much.so don't need to worry about them.

I read somewhere as I remember vaguely that aspect ratio should be lower than 5(?) for better stability and accuracy as I remember,is it true?

akidess · July 1, 2013, 05:35

Lower is better, but there is no fixed rule. In some applications you cannot avoid high values, and still get reasonable results.

Recommended reading: http://www.sharcnet.ca/Software/Flue...ug/node167.htm

July 1, 2013, 04:31		#2
akidess Senior Member Anton Kidess Join Date: May 2009 Location: Germany Posts: 1,377 Rep Power: 29	I believe openness is only a concern when doing CAD import. CAD geometries tend to be not perfect and can lead to unwanted gaps in your geometry/mesh on import. The values in your log file are good (close to zero). immortality likes this. __________________ On twitter @akidTwit Spend as much time formulating your questions as you expect people to spend on their answer.

July 1, 2013, 05:27		#3
immortality Senior Member Ehsan Join Date: Oct 2012 Location: Iran Posts: 2,208 Rep Power: 26	Hi Anton thanks so much.so don't need to worry about them. I read somewhere as I remember vaguely that aspect ratio should be lower than 5(?) for better stability and accuracy as I remember,is it true? __________________ Injustice Anywhere is a Threat for Justice Everywhere.Martin Luther King. To Be or Not To Be,Thats the Question! The Only Stupid Question Is the One that Goes Unasked.

July 1, 2013, 05:35		#4
akidess Senior Member Anton Kidess Join Date: May 2009 Location: Germany Posts: 1,377 Rep Power: 29	Lower is better, but there is no fixed rule. In some applications you cannot avoid high values, and still get reasonable results. Recommended reading: http://www.sharcnet.ca/Software/Flue...ug/node167.htm immortality likes this. __________________ On twitter @akidTwit Spend as much time formulating your questions as you expect people to spend on their answer.

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