Free size or size optimization with covering option

Rahul_P1

Hi,

I would like to do a size optimization on multiple PCOMPG, is it possible ?
Which desvar can I use ? and which CARD --> SZTOSH ?
Please could you send me an example of input data ?

Is it possible to do a free size optimization with PCOMPG ? with many zones ? please give me an example.

Also, I have two PCOMPG which overlap.
My question is: How can I optimize this two PCOMPG without moving the covering surface ?

Do you understand that I explain ?

Many thanks,

Regards,

Benoit MATTE

Rahul_P1

Benoit,

Yes it is possible to do a size or a free size when you use pcompg to define your laminates. You will be creating a desvar and a property relationship for each laminate (each pcompg), It is also possible to have multiple zones,

just refer to

RADIOSS, MotionSolve, and OptiStruct Tutorials > OptiStruct > Size Optimization:
OS-4020: Composite Bike Frame Optimization

This uses pcomp but the procedure is the same, The model has several components with different pcomps for each component, this is similar to zones with different property (hence laminate definitions) definitions.

About your last question, I am afraid I would need a figure explaining your configuration and what you mean by movement etc.

Perhaps you would consider ply based modelling to Zone-based modeling, the limitations of zone based modelling include
Data duplication
Difficult to interpret ply shape
No relationship to the mfg process
Model updates require multiple steps

It may be a good approach to start with ply based modelling, you can always 'realize' your plies for a zone based model later (simple to do this) if you need to this way

Rahul_P1

ok thanks
I create one Free size desvar by PCOMPG but when I run the optimization and analyze result in thickness, it seems that it does not change.
With many plies in a PCOMPG a free size optimization can move thickness of each ply ?

Many thanks,
BM

Rahul_P1

Benoit,

Yes,

In a Free size composite optimization, by varying the thickness of each ply with a particular fiber orientation for every element, the total laminate thickness can change ‘continuously’ throughout the structure, and at the same time, the optimal composition of the composite laminate at every point (element) is achieved simultaneously.

At this stage, a super-ply concept should be adopted, in which each available fiber orientation is assigned a super-ply whose thickness is free-sized.
So if you have maybe 5 plies with a particular orientaion, group them and give this 'super Ply' the sum of the thicknesses of all these 5 plies, you must also ignore the stacking sequence at this stage.

You can once again establish the number of plies when you do a ply based sizing optimization with relevant manufacturing constraints and proceed to shuffling or you can do this by yourself after the free size optimization.

Rahul_P1

ok many thanks