Dear Robert Cimrman,

I am trying to implement elastic inclusion problem.  It is a 2D mesh with an inclusion(and therefore eigenstrain) at mesh centre. I developed my codes(as attached) based on following two previous issues.

https://groups.google.com/forum/#!searchin/sfepy-devel/Ronghai/sfepy-devel/ru_xHEw1DFo/Ni7rIOkJA6cJ
https://groups.google.com/forum/#!searchin/sfepy-devel/elastic$20periodic$20boundary$20condition|sort:relevance/sfepy-devel/VpVHXS7Jh0Q/bDNs1JP4x94J

But I have troubles with the boundary conditions. I would like to try two kinds of boundary conditions:
(1) Top and bottom boundaries: uniaxial loading(or surface traction). Left and Right boundaries: periodic. I used "dw_tl_surface_traction" but some errors come out.
(2) Periodic at all boundaries. I think there must be a easy way for this, but failed to find out in SfePy documentation and mailing list.

Could you please give me some help. Thanks.

Regards
Ronghai