Maria Fernanda Velasquez
Greetings Peter
I reviewed the simplified model you shared with me and since I am not that experienced with the software, I need to investigate the different options you use, to better understand and be able to make the changes from rigid to flexible and give it a thickness.
I don't know how:
How to create the surface.
Do you do the gravity increase
The options you use in contacts and meshing.
The APDL commands 
If you have any information (videos or papers) that you can share with me regarding these topics, it would help me a lot to understand. I am going to study that part to understand the model.
Additionally, I have some questions:
When you mention changing the container from rigid to flexible, do you mean the simplified model you shared with me?
Can I modify from my container geometry the aluminum profiles to sheet bodies with only four faces for each one? or should I do it from scratch?

Maria Fernanda