Govindan Nagappan
Ansys Employee
Try reducing the mesh size and see if it helps. Failed mesh image shows large size on the planar face, but the thickness is very small. So the aspect ratio is probably high(poor mesh quality)
Or you can turn off quality checks in details of mesh and see if it helps
See if parts are sweepable or if you can use Multizone mesh. You can control the mesh sequence. Select a body and generate the mesh on selected bodies. Then mesh the adjacent connected bodies.
Or if you can use contacts instead of shared topology, that should make meshing easier