A comparative analysis of the neutronic performance of thorium mixed with uranium or plutonium in a high‐temperature pebble‐bed reactor

Abstract

High-temperature gas-cooled reactors (HTGRs) present an interesting concept for the next generation of nuclear reactors due to them having many advantages. In particular, their fuel is based on coated particles known as tri-struc-

Effects of Fuel Density on Reactivity Coefficients and Kinetic Parameters of Pebble Bed Reactor

“…The structural components of the reactor core such as graphite reflectors were easily modeled while the coolant in the reflector side and especially, the reactor shutdown and control systems require special effort in modeling. The modeling and calculations performed in this study were demonstrated successfully in various publications [11][12][13][14][15][16][17][18][19][20][21][22].…”

Neutronic and burnup characteristics of potential dual‐cooled annular ( Th‐ 233 U‐ 235 U ) O 2 fuel for the advanced pressurized water reactors: An assembly‐level analysis

“…Thorium‐based fuel is one example of such an alternative fuel technology. Thorium and its based fuels have the lowest neutron poison productions (eg, Xenon and Samarium), and the addition of thorium could reduce the amount of burnable poison required 6 . Thorium‐based fuel has also higher thermal conductivity than uranium‐based fuel, especially at low temperatures, and its thermal expansion is less than that of uranium‐based fuel, and its melting point is very high (3300°C) 7 .…”

“…Thorium‐based fuel has also higher thermal conductivity than uranium‐based fuel, especially at low temperatures, and its thermal expansion is less than that of uranium‐based fuel, and its melting point is very high (3300°C) 7 . However, because thorium, primarily in the form of Th‐232, is a fertile material, it must be combined with a fissile nucleus such as U‐235, or U‐233 and Pu‐239, to initiate the fuel cycle 6 . Thorium‐based fuel cycle contributions have been thoroughly examined as potential replacements for many established reactor technologies such as molten salt reactors, 8,9 advanced prismatic and pebble‐bed high‐temperature reactors, 4,6,10 as well as Generation III and III+ pressurized water reactors 10‐12 …”

“…Thorium and its based fuels have the lowest neutron poison productions (eg, Xenon and Samarium), and the addition of thorium could reduce the amount of burnable poison required. 6 Thorium-based fuel has also higher thermal conductivity than uraniumbased fuel, especially at low temperatures, and its thermal expansion is less than that of uranium-based fuel, and its melting point is very high (3300 C). 7 However, because thorium, primarily in the form of Th-232, is a fertile material, it must be combined with a fissile nucleus such as U-235, or U-233 and Pu-239, to initiate the fuel cycle.…”

“…7 However, because thorium, primarily in the form of Th-232, is a fertile material, it must be combined with a fissile nucleus such as U-235, or U-233 and Pu-239, to initiate the fuel cycle. 6 Thorium-based fuel cycle contributions have been thoroughly examined as potential replacements for many established reactor technologies such as molten salt reactors, 8,9 advanced prismatic and pebblebed high-temperature reactors, 4,6,10 as well as Generation III and III+ pressurized water reactors. [10][11][12] As mentioned, extensive research has been conducted into the potential contribution of thorium to the fueling of various types of reactors.…”