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Regarding Free Shape Optimization Error?

Hello friends,

Right now I am doing free shape optimization, in which I have selected some particular nodes where I have higher stresses, but still got error Shows CPENTA element is distorted, you can see the Image related to error.

Please give me solution.

Moreover, Is it possible to solve free-shape as well as shape Optimization together?

Thank you,

Best Regards,

Jay

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Altair Forum User

Hi Nayak,

Include REMESH option in OptiControl

Go to Optimization>>OptiControl>>REMESH>>1 and check if this helps.

Usually for shape optimization Hexa is a better choice of elements.

Altair Forum User

Thank you Prakash,

I have used shape optimization in my model and I have found drastic reduction in stress by applying Design variables as a shape optimization. But in Free shape optimization I have to select nodes, at that time I can't see that amount of change in stress!! In free shape also I have given the same constraint which I have applied in Shape Optimization: that is Mass of my model.

Please give me some Idea or if you have any example then share me.

Thank you,

Best regards,

Jay Nayak

Altair Forum User

@Nayak

Did you use stress constraint for both free shape and shape?

Free shape and shape may not give same result

Altair Forum User

I have given Mass as a constraint in both the case: Free shape and Shape opti. But for Shape Optimization everythings goes fine.

But what kind of constraint I should take for Free shape? Should I limit at perticular nodes about their stress limit?

I got the result as you can see in figure, in node vise. despite I have also given design variables.

Thank you

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Altair Forum User

Nayak,

refer to this tutorial on how to limit stress using Free shape optimization.

Unable to find an attachment - read this blog

Altair Forum User

Thank you for your suggestion of the related tutorial, but I have to take constraint in my simulation. In the tutorial they have taken without any constraint for Freeshape. Secondary I got warning regarding crack found in the element, but I guess there is not crack in the geometry. I did also REMESH = 1 and activated. still got error of Mesh distortion and penta mesh element distortion.

Error: CPENTA Element is distorted (zero or negative Jacobian)

and what is 'htdrv module', It shows error occurs in that module. Please give me some suggestions.

Thank you,

Best Regards,

Jay

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