Streamfunction

[leo mangalath]

Hi all,

I have a few questions about calculating the streamfunction in dedalus.

I noticed that every time I try to define v-component as a boundary condition for the streamfunction, the matrix turns singular. However, when defining a u-component I dont get this issue. For some cases (with a non zero v-velocity at the wall for example) defining the boundary conditions just in terms of u doesnt get me the correct streamlines.

Do you know why this singularity issue when defining a y-derivative BC is present?

 I have attached my script for the streamfunction calculation and the velocity input file (blowing and suction in the form of a travelling wave).

 I have also attached a picture showing the calculated streamlines and a quiver plot on top of that, calculated straight from the u_input file, which depicts the deviation especially at the top.

Thank you in advance!

Best, Leo