[firedrake] Delete element to model notch/crack in an Extruded Mesh

Hi, I have created a hexahedral mesh of a pipe by extruding an annulus meshed with quadrilateral elements. I need to model a notch or crack by deleting elements from the mesh. I looked into mesh.py but I am not confident of what functions I need to look into. Can anyone help me with a simple code to delete an element for a given extruded mesh or list the functions that I should look into? Thanks -- Abhishek Venketeswaran NETL Research Associate - ORISE National Energy Technology Laboratory Department of Energy abhishek.venketeswaran@netl.doe.gov Work: 412-386-4833 Mobile: 716-507-7890 www.netl.doe.gov<http://www.netl.doe.gov> [cid:ac47681d-8c17-436a-9f44-a590b712d3bd]