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Euler Lagrange Equation

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I am not able to solve an equation as mentioned in the attachment which is nothing but the EULER-LAGRANGE equation which was obtained through variational principle by minimising the strain energy and the constraint equation with respect to the unknowns u and v.

Iam not able to figure out how to implement the inequality constraint and the lagrange multiplier in the coefficient form PDE. Kindly help me in figuring this out. Just to make the system have a unique solution i have applied a dirichlet contion as well.

The COMSOL file contains the differential equation without any constraint imposed. If the constraints are imposed it would look like the equation as in the "Attachment".

Kindly help me in solving this.


0 Replies Last Post 3 mars 2016, 01:28 UTC−5
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