Implications of NbTi short-sample test results and analysis for the ITER Poloidal Field Conductor Insert (PFCI)

Zanino, R.*; Bagnasco, M.*; Baker, W.*; Bellina, F.*; Bruzzone, P.*; della Corte, A.*; Ilyin, Y.*; Martovetsky, N.*; Mitchell, N.*; Muzzi, L.*; Nijhuis, A.*; Nunoya, Yoshihiko; Okuno, Kiyoshi; Rajainmaki, H.*; Ribani, P. L.*; Ricci, M.*; Salpietro, E.*; Richard, L.*; Shikov, A.*; Sytnikov, V. E.*; Takahashi, Yoshikazu; Taran, A.*; Vedernikov, G.*; Zapretilina, E.*

As the test of the PFCI is foreseen at JAERI Naka, Japan, it is essential to consider in detail the lessons learned from the short NbTi sample tests, as well as the issues left open after them, in order to develop a suitable test program of the PFCI aimed at bridging the extrapolation gap between measured strand and future PF coil performance. Here we consider in particular the following issues: (1) the actual possibility to quench the PFCI conductor in the TCS tests before quenching the intermediate joint, (2) the question of the so-called sudden or premature quench, based on SULTAN sample results, applying a recently developed multi-solid and multi-channel extension of the Mithrandir code to a short sample analysis; (3) the feasibility of the AC losses calorimetry in the PFCI. These results show that Tcs measurement and the calorimetric measurement of AC losses will be carried out successfully. However, we need further analytic works for the problem of the sudden quench.