How to creat surface from this geometry with icemcfd
 

Dearfriends:
i have create the following channel. but could you please tell me how to creat two surfaces.
the middile wavy wall was created with many segment. but icemcfd can only creat surface with 2-4 lines. how to combine the way wall segments into one line

Just reapproximate or use "surfces from curves" instead of "2-4 curves".

you can create one big surface, and use build topology to automatically split it when curves are met...