The elements at the bottom of the circular domain located at the ends of the blue arc are too deformed. They seem to have a corner with angle close to 180 degrees. Can you post a zoomed-in figure to confirm this?
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I think it may be that the element is too deformity in the mesh .
The elements at the bottom of the circular domain located at the ends of the blue arc are too deformed. They seem to have a corner with angle close to 180 degrees. Can you post a zoomed-in figure to confirm this?
You can try to mesh the half-disk following the strategy in the following figure: http://www2.mps.mpg.de/projects/seismo/glass/cubed_sphere_grid_v1.jpg
Thank you !the reason is right !