Hi Daniel,
Thanks for your prompt help. I'm trying to solve the instationary incompressible Navier-Stokes equations at not very high Reynolds number(~100). It seems that this kind of fluid should be described by Navier-Stokes flow instead of Stokes flow(Re<<1)[1]. The "Vector-Valued" method I mean solving the Navier-Stokes equations using the same form of velocity as in step-22, step-32 rather than as "scalar" variables like in step-35 using the projection method. The step-22, step-32 are for stokes flow but not for Navier-Stokes flow. I have tried to extend them to solve Navier-Stokes equations by adding the convection term into the left hand matrix but always failed. Thanks very much! Regards, Jack [1] https://en.wikipedia.org/wiki/Stokes_flow 在 2017年3月26日星期日 UTC+8下午5:45:48，Daniel Arndt写道： > > Jack, > > Is it possible to extend your code to time dependent Navier-Stokes >>> equations? >>> >>> I want to solve the unsteady Navier-Stokes equations using the >>> *Vector-Valued* method, but I did not get any good idea from the >>> tutorial examples (step-22, step-32, etc.) for Stokes flow. >>> >> The velocity in the Stokes and Navier-Stokes equations is vector-valued, > but what exactly do you mean by "vector-valued method"? > step-22 considers the stationary Stokes equations and so does step-32. > Basically, you just have to add a time discretization to your equations. > Have a look at the examples that deal with time-dependent problems [1]. > E.g. step-26[2] considers the heat equation using theta-time stepping > scheme and might be a good starting point. Step-35[3] uses a projection > method in combination with a BDF(2) time discretization to solve for the > instationary Navier-Stokes equations. > > Best, > Daniel > > [1] https://www.dealii.org/8.4.1/doxygen/deal.II/Tutorial.html > [2] https://www.dealii.org/8.4.1/doxygen/deal.II/step_26.html > [3] https://www.dealii.org/8.4.1/doxygen/deal.II/step_35.html > -- 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 dealii+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
