Looks like artificial wavy in stress

Hello.

I have a question.

I’ve attached a figure.
The figure shows pressure, stress xx, yy, zz.

Unlike pressure, stress looks wavy even though the solution converges in the given criteria (1e-5).

Do you have any idea or any experience?

Best regards

Sugnho

Hi Sungho,

the stress often looks quite noisy/wavy with over-/undershoots. This might looks incorrect, but is a result of the finite element solution only being continuous between cells, which means that its derivatives, and therefore stress and strain, have jumps between cells.
I created a pull request to change the default in ASPECT to output stress averaged per cell here: https://github.com/geodynamics/aspect/pull/3478
If you want, you can take a look at it to see if this makes your output look more reasonable.