Convergence difficulties composite shells
Convergence difficulties composite shells
(OP)
I am modeling a hexagonal system with shell elements, see added image. These shell elements are assigned a composite section with 2 materials (linearly elastic) and three layers. I am trying to compress this system transversely with a displacement controlled analytical rigid plane, but the analysis "never" converges. The bottom edge is locked with y-symmetry and the side edges are constrained from moving sideways. I want the system to buckle completely and be squeezed so much it only has about 1/4 of its height left. Any tips on how to improve convergence?
Things i've tried:
Tried both Penalty and Augmented lagrange as interraction property between analytical rigid plane and shell elements
Make the walls thinner (worked to some degree, but I need them to be quite thick)
Set poisson's ratio almost to zero
Fiddle around with general solution controls
Change mesh. (With S3 elements abaqus compresses the system much more than S4. With finer mesh, convergence decreases!)
Things i've tried:
Tried both Penalty and Augmented lagrange as interraction property between analytical rigid plane and shell elements
Make the walls thinner (worked to some degree, but I need them to be quite thick)
Set poisson's ratio almost to zero
Fiddle around with general solution controls
Change mesh. (With S3 elements abaqus compresses the system much more than S4. With finer mesh, convergence decreases!)





RE: Convergence difficulties composite shells
RE: Convergence difficulties composite shells
RE: Convergence difficulties composite shells
An explicit simulation will give a dynamic response so you will get oscillation (ie if you are using purely linear elastic materials there is no reason why these oscillations should dampen out when using displacement control) & not a quasi-static response.
RE: Convergence difficulties composite shells
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RE: Convergence difficulties composite shells