The Design and Analysis of the Cooling System of NBI Thermal Shielding for EAST A# Equatorial Port

摘要

To avoid the thermal damage induced by the neutral beam to the neck tube of Experimental Advanced Superconducting Tokamak equatorial port (A#), a thermal shielding (TS) is utilized to withstand the high heat load. For the TS, the cooling system is designed including the interface with outer main loop. Several layouts of the cooling circuits are compared before a determined option. In particular, thermal-hydraulic transportation of the cooling system is investigated using a large slenderness ratio mesh model. And a discrete method for heat loading is developed. It indicates that the heat affected zones are appearing in a center gathered distribution but scattering in the surrounding area. And the central heat affected zone assumes the peak heat flux on the surfaces of the Mo tiles. This is the dominant factor to the layout of cooling pipes due to the temperature limitation of the TS materials. As a result, a non-uniform layout for the cooling pipes in the heat sinks is obtained based on the computational fluid dynamic results.