How to set Dirichlet BC for a cylinder geometry?

Dear Pylith team,

I am wondering how to set Dirichlet BC for a cylinder geometry. In my case, cylinder is a better choice for making model geometry if we just consider the specific region of interest.

Next, we need to set boundary conditions. In PyLith, it’s simple to do that for the top and bottom surface. It’s also simple for the front, back, left, and right surfaces of a brick geometry (e.g., setting ZERO displacement on the direction bc_dof=0 or 1 ). However, for the cylinder geometry, if we want to set the radial displacement to ZERO and the tangential displacement free, how can we realize this?


PyLith does not currently support a Dirichlet BC in terms of tangential and normal coordinates. It only supports constraining degrees of freedom aligned with the Cartesian coordinate axes.