Test Results of the DPC-TJ-Thermal and Hydraulic Performances

Abstract

Thermal and hydraulic test results of the DPC-TJ coil, a 24kA-40A/mm² forced-cooled Nb₃Sn coil, are presented in this paper. The DPC-TJ coil was installed and tested between the DPC-U1 and U2 coils. The weight of the DPC-TJ coil is 2.8 tons and the total cooldown weight as the coil system is 23 tons. It took about 180h to cool the coils from room temperature to 20K. The DPC-TJ coil's heat load was 20W at zero transport current and 40W at 24kA, the rated charging state. The pressure drop in the DPC-TJ coil was measured and agreed well with the empirical formula which was at the design of the DPC-TJ coil. AC losses and inductive by heat input cause the quick decrease of the helium flow rate at the coil inlet position. This phenomenon was analyzed, and one of the design standard was derived.