3-D SHIELDING ANALYSES OF THE VERTICAL AND MID-PLANE PORTS IN ITER

A three dimensional (3-D) shielding analysis of the International Ther monuclear Experimental Reactor (ITER) has been performed with the aim of calculating the nuclear heating on the magnet system, correlating i t to the existing vertical and horizontal ports. When these openings a re left unshielded, more than 50 kW are calculated for the upper half of Toroidal Field Coil system and two of the Poloidal Field Coils. A s imple plug, with same thickness as of the vacuum vessel can lower the heating to meet the imposed requirements.