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Old   July 18, 2014, 16:44
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Hi

If I reduce the scale of my mesh(Ex, from m to cm or mm), Can I increase the speed of convergence's process? or It's unhelpful?

Best regards,
Hassan
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Old   July 19, 2014, 07:20
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That's depends on your case . if you scale from m to mm may be you go from normal scale to macro scale and that's mean different case
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Old   July 19, 2014, 13:20
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Hi ahmad

First Thanks for your comment,
But I did n't understand exactly! Can you explain more?
I have a 3d mesh in m scale and I want replace it's scale with cm or mm for increase speed!

Best regards,
Hassan
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Old   July 19, 2014, 14:30
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Quote:
Originally Posted by hassanmaleki View Post
Hi ahmad

First Thanks for your comment,
But I did n't understand exactly! Can you explain more?
I have a 3d mesh in m scale and I want replace it's scale with cm or mm for increase speed!

Best regards,
Hassan
firstly I think you mean overall simulation time by "speed" ?is it ?
secondly , when you scale case from m to mm ( as example ) that's mean you mesh a case on mm dimension not on m dimension , so that is different cases ?
thirdly what is your case dimensions ?
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Old   July 20, 2014, 11:55
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Quote:
Originally Posted by hassanmaleki View Post
Hi

If I reduce the scale of my mesh(Ex, from m to cm or mm), Can I increase the speed of convergence's process? or It's unhelpful?

Best regards,
Hassan
No....

On the contrary if it is non-physical you will expereince divergence or very slow convergence...
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Old   July 20, 2014, 13:16
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Hi
Thank you Ahmad and Sijal!

I simulate air flow in a room and I have 3d mesh! but convergence process is very slow!

so,according what you said this work is not helpful and maybe divergence!

Best Regards,
hassan
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Old   July 20, 2014, 13:34
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Quote:
Originally Posted by hassanmaleki View Post
Hi
Thank you Ahmad and Sijal!

I simulate air flow in a room and I have 3d mesh! but convergence process is very slow!

so,according what you said this work is not helpful and maybe divergence!

Best Regards,
hassan
Why you want to scale your mesh?

Usually it is done to get the units to which model is drawn.

May be if you are studying some wind tunnel model and want to replicate that experiment then you choose this option, but in that case you need to change your boundary conditions...
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Old   July 21, 2014, 15:36
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In a few words, if you scale down the model with the mesh you have a different geometry and results will be different, with same boundary conditions.
You need to simulate the real geometry and adapt the mesh to your needs.
If you have the real geometry and you are asking for reducing only the mesh size, then in general convergence could be better, but maybe you have to change wall function.
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