Development of innovative reactor-integrated coolant system design concept for a small modular lead fast reactor

Abstract

The report describes the development of an innovative magnetohydrodynamic (MHD) space-integrated coolant system design concept for the small modular lead fast reactor called the ubiquitous, rugged, accident-forgiving, nonproliferating, and ultralasting sustainer reactor. The coolant system efficiency was analyzed based on space-integrated geometric and electromagnetic variables related to the circulation of lead-bismuth eutectic (LBE) liquid metal coolant in a reactor with a thermal output of 100MW(t) and using the MHD principle. The objective of the system is to optimize the circulation of the noncontacting liquid metal coolant without any internal structure, such as an impellor or sealing part, to transport the LBE with high electrical conductivity in the reactor. The concept was first applied to the pool-type integral leading facility for lead-alloy cooled advanced small modular reactor, which serves as a scaled-down experimental facility for the ubiquitous, rugged, accident-forgiving, nonproliferating, and ultralasting sustainer reactor, for characteristic analysis of the coolant system subject to the requirements of a developed pressure of 8456Pa and a mass flow rate of 21.37kg/second. The MHD core blanket, which was attached to the upper part of the pool-type integral leading facility for lead-alloy cooled advanced small modular reactor and wrapped it cylindrically from the outside to form an annular passage, was designed for the forced circulation of liquid LBE taking into account its internal space and the high operating temperature of 440 degrees C. Design variable analysis provided the optimized geometric and electromagnetic parameters of the MHD driving system based on the electromagnetic characteristics in the coolant passage of the reactor. This forced cooling system concept based on MHD propulsion is structurally simple and will enable significant space reduction and increased power for small modular lead fast reactors. It was also determined that safe long-term reactor operation could be ensured without requiring particular maintenance because the operation does not involve fluid contact.