hi all: how to build subdomain,i use CFX5.5.1

in the first place,you can creat a B-rep solid,then creat domain, at last you need creat fluid subdomain with the solid that you have just created.

thanks but i want to know B-rep solid means what? how can i creat solid with two domain,one is the fluid domain another is the solid subdomain!

See the tutorial no. 14 of conjugate heat transfer in heat -exchanger from online help of advaced tutorials. It will give u very good understanding of solid-subdomain. I would say create solid sub-domain and give tamplate solid as material u want.