Learning Forum

[jmcclos8]

Hi, I am simulating a pressure vessel in ansys. I initially created a shell model of the vessel and performed a mechanical simulation to understand stresses as the vessel goes to vacuum. In the shell model I noticed several stress concentrations in one area of the model. I created a more detailed submodel of this area of the vessel with solid parts. The model is shown below.

I noticed the formation of several stress concetration largely in the two areas shown in the image below. 

Is there any way to determine whether these stresses are an artifact of the model or are physical?

Any help would be much appreciated.

Best regards,

Jacob McCloskey

[Ashish Khemka]

Hi Jacob,

The stress seems to be on sharp edge. Can you further refine the mesh and see how the spread of the stress is? What is the failure criteria? Is this stress above allowable in this region and have a good spread?

Also, check if the loads and boundary conditions are applied properly or not (w.r.t to the prototype). These are some points to look for.

Regards,

Ashish Khemka

 

[jmcclos8]

Hi Ashish,

Thank you for youre response. I have rerun the simulation with a tighter mesh near the stress concentration. I have embedded an image of this below. In term of failure citeria, the vessel is made of 5052 aluminum that will be TIG welded. These stress concetrations are in the heat affected zone of the weld so failure is somewhere in the region of 100 MPa.