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Aalo Atomics achieves criticality on July 4
Executive Order 14301 set an ambitious goal for at least three test reactors to achieve criticality by July 4. Two private companies participating in the Department of Energy’s Reactor Pilot Program—Antares and Valar Atomics—reached this stage earlier in June, and Deployable Energy—participating in the DOE's Nuclear Energy Launch Pad—became the third last week.
In the last few weeks, reports indicated that Aalo would be next, reaching criticality at Idaho National Laboratory with a low-enriched uranium–fueled, sodium-cooled reactor on or near the target date set forth by President Trump’s EO 14301. In the early hours of July 4, Aalo’s critical test reactor—a full-scale zero-power version of its planned 10-MWe Aalo-X—did just that, becoming the fourth DOE-authorized reactor to hit the milestone.
Liam Russell, Adriaan Buijs, Guy Jonkmans
Nuclear Science and Engineering | Volume 176 | Number 3 | March 2014 | Pages 370-375
Computer Code Abstract | doi.org/10.13182/NSE13-8
Articles are hosted by Taylor and Francis Online.
G4-STORK (Geant4 Stochastic Reactor Kinetics) is a time-dependent Monte Carlo particle physics code for reactor physics applications. G4-STORK was built using the Geant4 Monte Carlo toolkit and is designed to model the continuous evolution of a population of neutrons in space and time. From this evolution, various important reactor physics quantities can be calculated, including the reactivity of the system and the entropy of the neutron spatial distribution. System properties, such as the temperature of a material, can be changed incrementally to approximate time dependence. Thus, G4-STORK can be used to model reactor kinetics and was used to simulate a system that underwent an instantaneous increase in temperature.
