The center post alternate design version for volumetric neutron source based on spherical torus

A spherical-torus type facility is one of the main candidates for a volumetric neutron source. The normal conducting magnet system of this facility is characterized by harsh operation conditions: high level of irradiation, ohmic heating and electromagnetic loads, which is why more attention should be paid to the center post (CP), an inboard part of the single-turn toroidal field coil. The alternate design version of the CP is developed with consideration for technological producibilities. The CP consists of the core and two extensions installed on the core ends by a press fit. The core is assembled from a rod and coaxial tubes and each extension consists of coaxial tubes successively set on the core. The thermo-hydraulic analysis of the CP is carried out taking into account the ohmic and neutron heating, as well as conductor resistivity increase after irradiation. Maximum conductor temperature does not exceed 200°C. The CP stress analysis shows that all applied loads (volumetric electromagnetic forces; nonuniform heating; water pressure in the cooling channels; dead weight and hot fitting) lead to the maximum stress intensity of 260 MPa.