Hello Jean-Paul,
Thank you for the help. Well, the actual situation is more complex, requires a generic solution, but it simplifies into a calculation of total quantity through a boundary. For instance, a simple case: say we have heat or mass transfer problem (or any scalar quantity) and specified some boundary conditions (problem-specific), how to get the total heat/mass passing through the specified boundary? Theoretically, the equation is something like (c is concentration here): <https://lh3.googleusercontent.com/-MWUI0byfiww/V-Viw0UincI/AAAAAAAAAAo/Z_b79mL9Rv0kYw9TqBkbn3m_qcBnIKwNwCLcB/s1600/eq200.gif> Honestly, I do not understand the theory in the tutorial 44 (it's completely out of my area). Dragan On Friday, September 23, 2016 at 5:56:16 PM UTC+1, Jean-Paul Pelteret wrote: > > Hi Dragan, > > What is it that you're trying to evaluate? Although you don't specifically > mention it, as you're wanting to do this in post-processing I presume that > you're wanting to evaluate something to do with the solution? If so, then > you can use the get_function_values > <https://www.dealii.org/developer/doxygen/deal.II/classFEValuesBase.html#a3f84ee49f0fbb32bfe01b2f4a473bb47> > and get_function_gradients > <https://www.dealii.org/developer/doxygen/deal.II/classFEValuesBase.html#a69c63f8be0311c8970253276ac7df138> > > associated with the FEFaceValues > <https://www.dealii.org/developer/doxygen/deal.II/classFEFaceValues.html> > class to extract the solution at the face quadrature points. > > As a further example, in step-44 > <https://www.dealii.org/developer/doxygen/deal.II/step_44.html> a > boundary integral is evaluated to compute the nodal contributions of a > force applied to a surface of a body. > > I hope this helps. > J-P > > On Friday, September 23, 2016 at 6:29:37 PM UTC+2, [email protected] > <javascript:> wrote: >> >> Hello guys, >> >> I searched the forum about how to calculate the surface integral over a >> boundary (during the post-processing) and found one post, where he was >> directed to the step-12. I am not sure if I can understand from there. >> Any directions how to do it or some other place to look? >> Thanks. >> >> Dragan >> > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
