Design Framework and Simulations of a Radiation Shield and Heat Exchanger for the Princeton Field-Reversed Configuration Fusion Reactor

Abstract

This thesis establishes the fundamentals for designing a radiation shield and heat exchanger device for the Princeton Field-Reversed Configuration (PFRC) reactor. The device must capture neutron radiation, X-rays, and microwaves while effectively carrying heat out of the system using a coolant. Two design concepts were proposed: layered shell and packed bed. The thermal performance of a layered shell device was evaluated under varying flow rates and heat loads with a parametric study on design parameters, such as the number of cooling channels and the total coolant volume. Using numerical simulations, key performance metrics including maximum temperature and pressure drop were evaluated. For the layered shell, a nondimensional parameter Π is defined to represent the ratio of cooling capacity to thermal load. A logarithmic relationship between maximum temperature and Π is devised such that, given a maximum temperature limit, a critical value Π* can be calculated under which the system overheats. To start development on a packed bed design, a method was developed to randomly generate a slice of the packed bed which uses periodic boundaries and symmetry to represent a full bed. This method provides a starting point for CFD simulations to prepare for large-scale experiments. These findings provide insight into the design and optimization of a joint shielding and heat exchanger device, providing a basis for future improvements in swiftly designing and manufacturing an outer shell for the PFRC.