S11 stress for cylindrical geometries 1

[mdama]

Hello
1) What does S11 (Not longitudinal in my case) stress mean for a cylinder? Does It mean principal stress along x direction? or It mean like circumferential principal stress?
2) In my result, the von Mises is less than the yield stress but S11 is bigger than yield stress and I see some plastic strain contour PE in my result. Should I consider S11 to compare with yield stress or should I consider von Mises to compare with yield stress?

Thanks

 

[FEA way]

When you transform the results to cylindrical coordinate system, S11 is radial stress. Otherwise it’s just a normal stress in X direction. For comparison with yield strength you should use von Mises stress.

 

[mdama]

Thanks, How can I get circumferential stress (r-theta)? And What is S22? Because S22 is also along radial.

 

[FEA way]

You have to create cylindrical CSYS and use Result —> Options —> Transformation first. Then S11 will be radial stress, S22 will be hoop stress and S33 will be axial one.