This example studies the time dependent decay from introducing standing vortices in a periodic domain. Due to the even spacing and counter rotation, the vortices will stay in place and simply loose intensity with time, and eventually the flow will return to a perfectly steady state. This is in fact one of the few model problems with and analytical solution to the non-linear incompressible Navier-Stokes equations
The two-dimensional flow problem is solved for a unit square with k = 2π and the exact solution as boundary and initial conditions.
This model is available as an automated tutorial by selecting Model Examples and Tutorials… > Fluid Dynamics > Vortex Flow from the File menu, and also as the MATLAB simulation m-script example ex_navierstokes5. Step-by-step tutorial instructions to set up and run this model are linked below.
