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How to implement inequality constraints directly in dolfin?

+2 votes

Does anyone has experience with inequality contraints in dolfin? I know this has to do with Lagrange multipliers and rewriting the weak form somehow. Let's say you have an energy functional

E[u]*dx, such that E >=0 and u >=0 everywhere on the mesh

that you are trying to minimize. How do you add these constraints to the weak form?

asked Nov 26, 2014 by chaffra FEniCS User (1,830 points)

1 Answer

+1 vote

Formulate your problem as a variational inequality and look at

dolfin-demos/undocumented/contact-vi-tao/

or

dolfin-demos/undocumented/contact-vi-snes/

answered Dec 3, 2014 by cmaurini FEniCS User (1,130 points)
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