Model identification of the temperature over the FTU cooled liquid lithium (CLL) limiter surface

In this work, a data-driven model procedure aimed at identifying the dynamical behavior of the thermal distribution over the limiter surface placed in nuclear fusion plant facilities is provided. In particular, we focused on experimental data collected in the in Frascati Tokamak Upgrade (FTU) where a cooled liquid lithium limiter (CLL) with a capillary porous system (CPS) technology is adopted. Thus, a nonlinear dynamical system, namely a Hammerstein-Wiener model, has been investigated and opportunely identified in order to predict the thermal distribution over the CLL. The identified system is able to predict spatiotemporal thermal information even in the worst case scenario when disruptive events occur during plasma experiments.