PROBLEM: Composite Optimisation

Hi Rowan,

I think the problem is coming from the buckling constraint. Since you have a upper bound of 1, solver will try to remove all the material and this makes the thickness of the laminate to zero.

Try to add a minimum laminate thickness constraint and check if you are able to avoid the error.

Hi,

Thanks for your reply. Even when I put the buckling constraint as lower bound as 1 instead of upper, it gives me the same error. If i add a shear strain constraint, the error does not appear anymore but the shear stress is not fullfilled. 

Rowan, 

Can you use a bound value close to the results?

Rowan,

also, try to give a manufacturable thickness to the plies and a laminate thickness constraint to the laminate so that the thickness cannot go to zero.

Hi Prakash,

I've got the same problem and I can't manage to solve it... I've shared the .fem file in your Dropbox.

Hope you can help me! It is urgent.

Thank you!

Hi Mcorsa,

I don't have access to dropbox link.

Please share the .fem file here or through personal message

Unable to find an attachment - read this blog

Hi,

Since I am using HW 12.0 here, after deleting the Freesize desvar in design variables optimization started.

FYI,

You get that error because the laminate thickness is going to zero. Provide a minimum laminate thickness constraint on the design.

Yes, I've provided a minimum laminate thickness contraint of 0.2mm in the Freesize desvar (picture) and I've updated it as composite size desvar

But if I have to delete this Freesize desvar, how I set the laminate thickness constraint?

<?xml version="1.0" encoding="UTF-8"?>

In 14.0 it should be fine.

Since I am using 12.0 I have to delete and update using composite size panel.