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<p>Dear Colleagues,</p>
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<p>I use the finite element method to solve my problem in Petsc.</p>
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<p>Mesh is defined as a regular mesh using DMDA. I have a special boundary condition which I do not know how to impose it in Petsc.
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<p>In a 2D problem, the domain is unit size, two degrees of freedom per node (u, v). I would like impose the following boundary condition:</p>
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<p>u(x=1) = -v ( y=1) and v(x=1 )= -u (y=1) .</p>
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<p>How can I impose such a boundary condition in Petsc? <br>
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<p>Thanks a lot. <br>
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<p>Best regards</p>
<p>Fengwen<br>
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<div class="PlainText">____________________________________________________<br>
Senior Researcher<br>
Department of Mechanical Engineering, DTU<br>
Nils Koppels Allé <br>
Building 404 <br>
2800 Kgs. Lyngby <br>
fwan@mek.dtu.dk</div>
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