Volume Fraction OSSmooth Iso_surface
Altair EmployeeHi,
I am establishing a topology optimization, the aim is to attend 50% of the original masse of my mechanical part.
I used this formula to calculate volume fraction:
Volume fraction = (total volume at current iteration – initial non-design volume)/initial design volume= 0.082
I put 0.082 as upper bound for volume fraction constraint and for Isosuface threshold parameter in Ossmooth when I export this file.
The problem that I am not getting a 50% masse of the original solid at the end.
Should I put 0.082 or 0.5 threshold parameter in Ossmooth?
I am I doing something wrong?
Thank you.
Answers
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Any response please
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Hi,
Sorry for a late reply.
First, let us understand how upper and lower bounds for volume fraction works:
Lower bound set to 0,4: the solver takes minimum 40% of the original volume to optimize. If you do not constraint an upper bound as well it might go to 100% if it is structurally necessary
Upper Bound set to 0,4: The solver is allowed to take maximum 40% or less material for the optimized design.
Now, if you are giving 0.082 as upper bound that means you are allowing to only take up to that percentage.
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Thank you for the reply.
Supposing like you said the upper bound is 40%, I am talking now about the value of threshold in OSSmooth, should it be 0.4 or other value??
Because for my case, my upper bound is 0.82, so I putted also 0.82 in threshold for OSSmooth and it didn’t give the good reduction percentage, I tried 0.5 and it gave me very close results to a total mass reduction.Thank.
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HI,
if your threshold is 0.82 on OSSmooth, meaning you are asking for a model with 82% less material, is that correct?
For example, If you key in 0 you will see a complete model without any material removed. If you provide say 0.3, this means the material whose density is less than 30% is removed.
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Thank you.
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