meshing of wavy fins
 

Hi
I would model a heat exchanger with finned wavy fins. I drew the model in Gambit and wanted to mesh the model. I meshed the four pipes as the following:
-Mesh face scheme for the Fin-Tube: Quad – Map
-Mesh volume ccheme: Hex/Wedge – Cooper
I then tried to mesh the other volume with “Hex/Wedge – Cooper” But a problem always happens when I mesh Volume 3.
I tried later to mesh the volume 1 and 2 with “Hex/Wedge – Cooper” and the volume 3 with the scheme “T grid” but the problem has remained.
Can someone help me how I can mesh the volume 1, 2 and 3 without errors.
Thanks