A review of multiphysics tools and methods to evaluate high temperature pebble bed reactors

Abstract

The Generation IV high temperature pebble bed reactor has garnered interest over the years as a viable solution for reducing overall carbon emissions. The potential for enhanced safety, increased efficiency, and reduced overall cost makes the high temperature pebble bed reactor design a top candidate for commercialization. However, detailed and accurate computational simulation of the concept is required for licensing and the complex nature of the design presents modeling challenges. Numerous approaches have been taken and many computational tools have been developed and/or adapted for capturing the multiphysics phenomena in high temperature pebble bed reactors. Within this manuscript, we briefly introduce some of the high temperature pebble bed reactor concepts proposed over the years. Then, we describe the key single-physics aspects and their limitations in scaling to full core modeling. We review the current approaches taken in developing multiphysics core and reactor coolant system models and the computational tools used. Finally, we conclude our review with a discussion on the recent shift in the pebble bed modeling paradigm. We provide suggestions on current and future development of high temperature pebble bed reactor modeling and simulation tools to align with current needs.