Material Orientation and how to choose interlaminar tensile stress as response in free shape optimization

Altair Forum User

Hello, Everyone! 

   I tried to use free shape optimization to minimize interlaminar tensile stress of L-shaped composite structure subjected to four point bending.  I have created 3D element model, used MAT9ORT and PSOLID to give properties.  The enforced displacement has been given. I have checked element normals and material orientation. The element normals is perpendicular to the curve surface. The material orientation is along with curve surface. However, when I check the stress results, the normal stress is totally wrong. I think maybe the material orientation is wrong.

So anyone knows how to set up the material orientation for 3D L-shaped composite structure? Besides, I want to know how to choose interlaminar tensile stress as response in free shape optimization process?

I tried the following method:  

Analysis-optimization-response-static stress-props, choose PSOLID-normal y.  

Is this method accurate? If not, please tell me how to do?

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Altair Forum User

Hi @Gregory1991

 

You can use Orientation review option available OptiStruct>> AeroSapce profile.

 

I dont see a way to include laminar stress directly, I will check and update to you soon on the same.

Altair Forum User

Dear Mr. Prakash Pagadala,

  Thank you very much. I am looking forward for your further reply about how to choose interlaminar tensile stress as response in free shape optimization. 

  I have checked the material orientation by using your suggestion. I also used the following method: Optistruct-2D-composites-material orientation, then choose whole elements-review. The material orientation obtained by these two methods is same. Are there any difference between these two methods? You can find the result in the attached figure. I think the material orientation is right.  

  However, when I checked the stress results, especially normal stress, the result is totally wrong.

  If you have time, could you please help me check the model?

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Altair Forum User

Hi @Gregory1991

 

Can you share the model files, results file and explain why you think the results are wrong.

 

Please use the FTP link in my signature below to share the model files.

Altair Forum User

  Thank you, Mr.  Prakash Pagadal.

  The model has been created using OptiStruct 13.0.

  When I did the experiment, delamination could be seen, and the normal stress of L-shaped structure corner part is the largest which I can get using Abaqus. However, when I checked normal stress of FEM results(ZZ direction in this case) using OptiStruct, the position of maximum normal stress is at the bottom of corner part.        

  I have shared the model, please check it.  

Altair Forum User

Hi @Gregory1991

 

I ran the model in 14.0 with updates and the I see the results which are at a different location compared to what you are saying.

 

 

Altair Forum User

Hi,  Mr.  Prakash Pagadal, 

  I also checked the result in OptiStruct 14.0, but the results is same with what I have said. 

  Could you please share your results? If possible, could you please help check the model I have sent to you? 

  Thank you in advance. 

Altair Forum User

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