spring 1944. Work at Los Alamos, Oak Ridge, and Hanford to design, build, and provide fissionable material for the first atomic bombs was shifting into high gear. In stark contrast, initial bomb project studies on the nuclear chain reaction and plutonium were winding down at the Chicago Metallurgical Laboratory, Argonne National Laboratory’s wartime predecessor. Even as others zeroed in on the ...

Fission fragments play a pivotal role in understanding the entire nuclear fission process, and their effects are widespread to all applications involving nuclear fission: reactor design and maintenance, waste removal, active and passive integration of nuclear materials, simulations, and the fundamental theories of fission. Currently, experimental data on the characteristic properties of fission...

Due to the diversity of fuel cycle simulator modeling assumptions, direct comparison and benchmarking can be difficult. In 2012 the Organisation for Economic Co-operation and Development (OECD) completed a benchmark study that is perhaps the most complete published comparison performed. Despite this, various results from the simulators were often significantly different because of inconsistenci...

The release of fission products and fuel materials from a molten-salt fast-reactor in hypothetical accident conditions was investigated. fast reactor this investigation features neutron spectrum, operating the thorium cycle, it uses LiF-ThF4-UF4 as salt. A coupling between severe code MELCOR thermodynamical equilibrium solver GEMS, so-called cGEMS, with updated HERACLES database used modeling w...

The Sodium-cooled fast reactor (SFR) features a closed fuel cycle for efficient conversion of fertile uranium and management of minor actinides. A full actinide-recycle fuel cycle is envisioned with two major options: One involves intermediatesized (150 to 500 MWe) sodium-cooled fast reactors with uranium-plutonium-minor-actinidezirconium metal alloy fuel, supported by a fuel cycle based on pyr...

A new acoustical sensing system for the nuclear power industry has been developed at The Pennsylvania State University in collaboration with Idaho National Laboratories. This sensor uses the high temperatures of nuclear fuel to convert a nuclear fuel rod into a standing-wave thermoacoustic engine. When a standing wave is generated, the sound wave within the fuel rod will be propagated, by acous...

In this electronic article we use the one-dimensional multigroup neutron diffusion equation to reconstruct the neutron flux in a slab reactor from the nuclear parameters of the reactor, boundary and symmetry condition, initial flux and . The diffusion equation was solved analytically for one single homogeneous fuel region and for two regions considering fuel and reflector. To validate the metho...

This paper provides an introduction to the reactor analysis capabilities of the nuclear power reactor simulation tools that are being developed as part of the U.S. Department of Energy’s Nuclear Energy Advanced Modeling and Simulation (NEAMS) Toolkit. The NEAMS Toolkit is an integrated suite of multi-physics simulation tools which leverage high-performance computing to reduce uncertainty in the...