Tie / cohesive contact between shell surfaces - Abaqus CAE.

[Olle Haglund]

Hi,

I am looking to make a simulation of a pressure vessel with a mix of metal (titanium) and composite parts. I am especially interested in the joint interface where the materials are bonded together.

I could make the simulation work fine and give realistic results when I only had two shells interacting with a tie contact. It was when I wanted to add a third layer (as shown below) to the model things started to go wrong - numerical singularities and unrealistic results. I have tried using cohesive contacts also according to instruction videos found on youtube with no good results.

composite
x x x x x - tie contact
metal
x x x x x - tie contact
composite

How do you go about modelling these kinds of joint interfaces, any tips?

 

[FEA way]

How are these parts connected in real life ? Are any fasteners used ? Also, can you share a picture showing how this region was modeled ?