3D mesh with boundary layer
 

Hi!
I need to generate a quite complex 3D mesh, with prismatic boundary layer on some surface.
As the ratio between width and height of boundary layer cells is about 7/1, the pyramid/tet mesh growing froma the side of such boundary layer can be of very poor quality. Moreover, the meshing algorithm could even fail in such situation.
Is there an alternative way to deal with this kind of meshes?
Francesco