Linear Stability Analysis Of A Full Triga Reactor Plant In A Closed Loop

This work investigates the dynamics of the TRIGA-Mark II located on the premises of Laboratorio Energia Nucleare Applicata (LENA) - Università degli Studi di Pavia; in particular, it focuses on the system stability in a closed loop, with thermal-hydraulics feedback and poison effects on reactivity. The stability analysis is based on the linearized equation system that describes the plant physics, encompassing neutronics, thermalhydraulics and reactivity feedback, and poison dynamics. The investigation of the linear approximation may provide relevant conclusions about the system stability; in particular, stability against small perturbations may often be deduced. Laplace Transform is applied to the linearized system to derive the transfer function that represents the system differential equations: its poles and zeros effectively define the system response to input perturbations. The system dynamics is studied through the analysis of the poles of the system transfer function and respect to different possible values of the moderator and fuel reactivity feedback coefficients.