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Calculate the corresponding nodal force on which a pointwise displacement is applied?

0 votes

Hi, everyone.

I use 

bc1 = DirichletBC(u.sub(1),  u1, loadpt, "pointwise")

to apply the pointwise displacements on the node "loadpt". I need to know the corresponding force exerted on this node.

Now, I can only use a small boundary surface to apply the displacement and to calculate the total tractions to get the exerted forces.

My problem is: how can I get the external force applied on the single node? Thank you!

asked Nov 6, 2016 by jywu FEniCS Novice (510 points)
edited Nov 11, 2016 by jywu

1 Answer

0 votes

Can anyone give any hint?

answered Nov 11, 2016 by jywu FEniCS Novice (510 points)

F_reaction = assemble(K_matrix)*u_sol

where u_sol is the nodal solution we obtained. Then we can extract reaction at any point

commented Dec 4, 2016 by hirshikesh FEniCS User (1,890 points)
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