i want to simulate part of my domain with (for example) laminar model and the other part wit (for example) k-omega...is it (in same way) possible?

Yes,you can set one part as laminar zone through FLUENT menu"Define-Boundary Conditions-Fluid-set", check the Laminar Zone on.

You can do these after you difined the turbulence model on through menu "Define-models-Viscous".

thank you very much linfan...but so that i want solve part of domain with RANS modelling and another one with LES modelling..it is not possible isn't it?