Hello, I’m currently trying to compute a boundary flux from the solution of an already solved PDE (Poisson equation) and I’m failing miserably. What works so far is uh = problem.solve() n = FacetNormal(mesh) ds = Measure('ds', domain = mesh, subdomain_data=dofsRight) flux = inner(grad(uh), n)*ds O…

Thank you for your replies. I finally found the solution which was how I defined the boundary. I should have used meshtags as in How to compute flux at particular boundary facets? . I do not need so far to compute the flux at every point of the boundary, only its integral, so I do not need the norma…

Hi, As stated in the link @francesco-ballarin posted, please use the search functionality for the forum before creating a post. This exact problem was solved in this post . Cheers

Compute a boundary flux after solving the PDE

dolfinx

francesco-ballarin April 23, 2024, 8:30am 2

See Read before posting: How do I get my question answered?

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Compute a boundary flux after solving the PDE

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