HHJ element on 2-D surface triangulations

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1

Can this be done in NGsolve?

2

Hi,

yes, you can. The space is called HDivDivSurface in NGSolve.

An example for Koiter shells is here:

https://docu.ngsolve.org/latest/i-tutorials/unit-6.1.4-shells/shell.html#

Best,
Joachim

3

Hi,

if you want to solve HHJ on surfaces without the other shell stuff as membrane and shearing terms, you can find a simple example attached

https://ngsolve.org/media/kunena/attachments/889/hhj_surface.py

Best
Michael

Attachment: hhj_surface.py

4

Great, thanks. And this can be adapted for curved surface triangulations, using Lagrange polynomials for the triangles?

5

Yes, correct, geometry is approximated by arbitrary order polynomially curved trigs or quads, and the HHJ spaces is mapped to the curved surface using double-sided Piola transform. All nasty derivatives are computed.