Automated control for nuclear thermal propulsion transient phases using point kinetics-based power balance modeling

Abstract

A new approach for implementing automated power-following control strategies applied to a full-core multiphysics system simulation using point kinetics to approximate transient reactor power response was conducted, with results compared to corollary analysis of an NTP system. Three control strategies were modeled and analyzed. Power-following controllers adequately managed desired engine performance and the thermal hydraulic and reactor power response to drum angle perturbation matched reported results. The hybrid-driven controller implementation exhibited greater engine control by adapting system response against dynamic engine behavior, and was utilized against a transient schedule for power ramp-up, throttling, and ramp-down engine sequencing. With the addition of a decay heat model incorporating system parameters to inform system shutdown cooling requirements, results were found to match corollary results, demonstrating point kinetics-based multiphysics models and feasibility of power-following controllers in engine environments. Temperature overshoots and power excursion events necessitate further investigation into heat transfer modeling and system discretization improvements.