Dear Alessandro,
The process for generating a torque-coefficient (Cq) surface is the same as for generating a power coefficient (Cp) or thrust coefficient (Ct) surface. You can do this with the standalone AeroDyn v15 driver e.g. see: Effecting of turbulence intensity on load of WT blade - #13 by Jason.Jonkman (more difficult, but allows the rotor to be flexible).
Best regards,