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Call a function in "mesh size" node
Posted 21 apr 2011, 18:47 GMT-4 Version 4.1 5 Replies
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A fluid flows in a rectangular 2-d channel (from the left to the rigth).
Global ->Parameters : H = 0.1 (it is the heigth of the channel)
Mesh ->Size -> Maximum element size : H
It works. But if I define a function
model ->analytic : myfun(x) = x/10
Mesh ->Size -> Maximum element size : myfun(H)
It doesnt works. I think that it means that a Mesh cannot be defined by a function. I tried to enter
Mesh ->Size -> Maximum element size : max(H)
and it didnt work. Can you confirm that a mesh cannot be defined with functions ? Is there a way to define a mesh with a complicated function of a global parameter ? (e.g, piecewise function of H)
Thank you.
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Indeed you cannot call a function, but you can write H/10 directly in the formula field
--
Good luck
Ivar
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Hi
Indeed you cannot call a function, but you can write H/10 directly in the formula field
--
Good luck
Ivar
I would like to set my "Mesh->MaximumElementSize" as a piecewise function. In fact, I found that:
1. when H is large, (MaximumElementSize = H/10) provides a good initial mesh (for adaptive mesh)
2. when H is very small, (MaximumElementSize = 1) provides a good initial mesh (for adaptive mesh)
In this case I need a piecewise function of H to set a good initial mesh regarless for all value of H.
How would you do that ?
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have you tried a chain of boolean expresions ?
Something like
h = 1/(1+ 2*(H<3) + 4*(H<6) ...)
It might work, haven't checked ;)
--
Good luck
Ivar
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Hi
have you tried a chain of boolean expresions ?
Something like
h = 1/(1+ 2*(H<3) + 4*(H<6) ...)
It might work, haven't checked ;)
--
Good luck
Ivar
I tried boolean expresion and unfortunately it is not accepted in the mesh size settings..
Any other ideas ?
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then for me it means that the mesh fields it accepts only "Parameters" (=Constants).
Pameters are be defined once at solver launch, and may be changed via a reference in a "Parametric sweep", or a "Solver Continuation sweep"
--
Good luck
Ivar