I am currently stuck in a problem related to ASPECT prescribed velocity conditions:
I am working on a 3d box crustal model, in which I would like to assign
different velocity components at different areas of the top surface.
In particular, I would like to assign velocities which are not perpendicular to the outline boundaries.
Is there a way to accomplish this?
if by “different components at different areas” you mean that on part of the surface you want to prescribe [x,y,z] and on a different part you want to prescribe [y,z] (for example), then you will need to create a new geometry that assigns different boundary names/ids to the respective regions. See “box with lithosphere boundary indicators” for an example.
If you just want to have more freedom in assigning velocities (perpendicular or not), you can write your own plugin (see source/boundary_velocity/) if the existing (functions, ascii data, etc.) are not flexible enough. In your plugin you can define for every point x,y,z what your velocities should be.