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hamid1 October 5, 2011 08:35

mesh
 
Hi

would you let me know how should be the growth factor in producing a mesh?

m2montazari October 5, 2011 15:20

hi,
it depends a lot!!
it depends to many things including the geometry, maximum no of cells you want, sizing of cells, problem characteristic, ....
but as a general rule, it is said that setting growth factors above 1.06 is not a good idea. and also in boundary layers and in paved meshes it could be a bit more.
yours,
mohammad

hamid1 October 6, 2011 04:56

thanks alot for responding..
actually i want to mesh a domain but dividing it to different zones in terms of mesh density, based on ur recommendation as a matter of rule of thumb it shouldn't be grater than 1.06 (i mean the size of neighbor mesh in the the neighbor zones), while for Boundary Layer it could be higher like 1.5 or so....
please correct me if I am wrong,

another question is grid validation, how is the rule of thumb for that, cause i stumbled many different ways, like making double or increasing 10% in comparing and so... i will also spread it out in another post to receive any idea?

thank u in advance

m2montazari October 6, 2011 14:41

hi,
[[while for Boundary Layer it could be higher like 1.5 or so....]] !!! no. 1.5 is very high. for BL it can be 1.1 or 1.2 as a maximum growth ratio.
and about grid study(validation),you can make a grid with n cells, then 1.5*n and finally 2*n. the difference between these three must be small and have a relation somewhat like n^2.
yours,
mohammad

hamid1 October 7, 2011 09:16

Hi Mohammad
Thank u for reply,
what about the growth factor between two cells in adjacent zones (if one want to mesh the domain by dividing it in different zone to making more dense in some specific areas)?
for the grid validation, I didnt understand about the difference relating to n^2, would u explain more,

Thank u


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