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Patterned Geometry Creation

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Hi,

I need to create 10,000 hollow fibers for my current model using the Matlab/COMSOL interface.
Is there any pattern function integreated in COMSOLthus avoiding the need to draw them in one by one?
Also, is there a function for hollow cylinder or do I need to draw two concentric cylinders?

Thanks!

1 Reply Last Post 14.02.2011, 14:38 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 14.02.2011, 14:38 GMT-5
Hi

yes there are repeat functions in v4, certain accep also "ranges" or "sets {}" to allow repetition, but before making your 10k objects, consider if you cannot use some symmetry to reduce the totalnumber of items, then ask yourself how many elements aour are creating, I would say in 2D >>1M elements, and how many DoF per elements ?16-32 (seethe KB for details) ? How much RAM required, and time to solve ?

These estimates are easy to run, and allows you to rapidly find out how big your model becomes, then you are less frustrated than when you discover some incompatibilities, after a few days of nice geometry generation ;)

in V4 use the external geometry core, I beliee its better than COMSOl internal one for so many geoemtrical elements,. but know that we have a 1000 element geometry here and we can wait up to 5 min for a geometry update (before even starting to talk about physics BC, mesh and solving ;)

Finlly, you might (very model dependent) also have the choice to consider one items and some surrounding and repeat the solution to cover a larger system by loca symmetry

A tube is for me 2 concentric circles, in union mode you do not need to take the differences etc

Do seriously consider the latest versions of V4 as there are many weaknesses corrected w.r.t the early v4.0

--
Good luck
Ivar
Hi yes there are repeat functions in v4, certain accep also "ranges" or "sets {}" to allow repetition, but before making your 10k objects, consider if you cannot use some symmetry to reduce the totalnumber of items, then ask yourself how many elements aour are creating, I would say in 2D >>1M elements, and how many DoF per elements ?16-32 (seethe KB for details) ? How much RAM required, and time to solve ? These estimates are easy to run, and allows you to rapidly find out how big your model becomes, then you are less frustrated than when you discover some incompatibilities, after a few days of nice geometry generation ;) in V4 use the external geometry core, I beliee its better than COMSOl internal one for so many geoemtrical elements,. but know that we have a 1000 element geometry here and we can wait up to 5 min for a geometry update (before even starting to talk about physics BC, mesh and solving ;) Finlly, you might (very model dependent) also have the choice to consider one items and some surrounding and repeat the solution to cover a larger system by loca symmetry A tube is for me 2 concentric circles, in union mode you do not need to take the differences etc Do seriously consider the latest versions of V4 as there are many weaknesses corrected w.r.t the early v4.0 -- Good luck Ivar

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