I am trying to create an internal flow volume in Fluent Meshing by wrapping the model consisting of 4 solid walls and patches on the inlet and outlet. The air flows through a long but narrow hole (5 mm x 800 mm, see image 1). I use curvature scoped sizing on all the bodies (image 2). The wrap volume does not fit the narrow region of the model (image 3). I guess, there is some minimal angle between edges of the wrap body which prevents it from "entering" the narrow area and filling the region completely.
I am new to Fluent, so I think I miss something basic. Thanks for any help!