How can divide surface after boolean?
 

In order to simulation for the flow in an axial fan with a motor and a shrouded duct, design process of geometry is doing (Fig. 1 a, b). (the fan is modeled as a upper cylinder.)

To extract fluid region for meshing, boolean operation is performed. A large cylinder, which include all other parts, is the target body. The fan and the motor, and the duct are tool bodies. After boolean operation, a surface of the fan hub and a surface of the motor are merged because its radius is same (Fig. 2).

However, boundary conditions of surfaces of the fan hub and motor are different. The fan hub should be rotated with constant rpm. On the other hands, the motor should satisfy no-slip boundary condition.

To implement different boundary conditions on the surfaces of the fan hub and the motor, how can divide or separate surface after boolean? Thank you in advance for your response.

Keuntae Park

Use the "Imprint faces" or "slicing" options.

Thank you for your help :)