hull resistance

Mirco

Hi, i m trying to investigate the resistance of a sailing yacht hull. I imported the hull from maxsurf, and with design modeller, i generated a solid body representing the water, after that i merged both body using the cut material operation. At this point i would you like to generate a second solid representing the air and attaching it with the other body. Could you give me an advice? is possible to develop it using the mirror operation? Thanks. Ciao