Hi there. This is my first post, curiously for my career thesis.

I am trying to simulate a Vent panel for a closed container (a bag filter).

The panel is an aluminum sheet that, when the internal pressure of the container increases, breaks, relieving the pressure, and avoiding a more severe explosion.

The panel is flanged at its ends.
- For the simulation design the panel of 800x800x2 mm.

- It should break at 0,01 MPa of internal pressure.

I'm trying to do this by a NonLinear simulation, and im having extremely big displacements but I'm not near a high stress value that breaks the panel. 

Does anyone know what could be wrong, and what I could try to do.?  

Thanks you in advance.

Edu ​​​​​​​