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-   -   [ANSYS Meshing] scale factor (http://www.cfd-online.com/Forums/ansys-meshing/95546-scale-factor.html)

 arun km December 22, 2011 02:17

scale factor

dear friends....
i am new to ansys..i want to know how we can select scale factor?
and what is the relation between scale factor and max element size ?

 PSYMN December 22, 2011 12:47

Scale factor lets you adjust all the sizes in the model at once...

By default, you should probably leave it as 1, which means that all the other sizes could be taken at face value.

Then if you want to make the model 20% coarser, you can come back and set the scale factor as 1.2. Get it?

Scale Factor times Max Element size gives you the largest element in your model. For Octree, this is the size of the initial subdivision when Octree is first initialized. You can read more about this in the theory sections of the Help.

If scale factor is larger than 1, it increases the mesh sizes throughout the model. If it is less than 1, it reduces them. Note, it changes how they behave, but it doesn't change the nominal values as you see them in the UI.

 Mmm2010 January 2, 2013 10:25

scale factor

ICEM CFD is unit - meter. I must create my geometry in millimeter. I made the geometry of the meters. I built grid. In Global Mesh Parameters field scale factor is 1 . I need to put 0.001 ? If to consider , that the geometry instead of millimeters built in meters? Thank You!

 PSYMN January 2, 2013 11:16

Mmm2010, you could use the scale factor that way, and many do, but I would just scale the whole model (Geometry => Transform Geometry => Scale) (x 1000).

I find it is more robust if you are not dealing with lots of significant figures to the right of the decimal place. Rounding tends to cut things down a bit.

ICEM CFD is really unitless, which means it is based on what ever the units were when you imported. If you want to think in units, try "Settings => Model/Units".

 Mmm2010 January 2, 2013 13:01

scale factor

1 Attachment(s)
Thank you very much. In my case
If i do Geometry => Transform Geometry => Scale then X,Y,Z scale factor=0.001
or
In main menu ICEM CFD Info=>Toolbox=>Units (in Units.jpg) i do'nt know i can change the unit of distance? I need to calculate all?

 Mmm2010 January 3, 2013 04:26

scale factor

My source geometry is mm.
The action: Geometry => Transform Geometry => Scale then X,Y,Z scale factor=0.001 is good. I got the real geometry.Another way, distance in units i can to change? m=0.001 sm=0.01 mm=1 and etc. Or scale factor in Global Mesh Parameters if the topology is built? Thank you.

 pawi October 28, 2014 22:04

Dear PSYMN :
I am new to this program as well. May i know how should i choose the scale if my drawing is extremely large, i have drawn A380 in actual size, but my seniors telling me that the result wont be accurate if i use the actual size, is it possible if i use 0.001?

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