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Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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El Salvador: Looking to nuclear
In 2022, El Salvador’s leadership decided to expand its modest, mostly hydro- and geothermal-based electricity system, which is supported by expensive imported natural gas and diesel generation. They chose to use advanced nuclear reactors, preferably fueled by thorium-based fuels, to power their civilian efforts. The choice of thorium was made to inform the world that the reactor program was for civilian purposes only, and so they chose a fuel that was plentiful, easy to source and work with, and not a proliferation risk.
A. R. Massih
Nuclear Technology | Volume 205 | Number 7 | July 2019 | Pages 992-1001
Technical Note | doi.org/10.1080/00295450.2019.1568102
Articles are hosted by Taylor and Francis Online.
Oxidation of UO2 fuel under off-normal and normal reactor conditions occurs when fuel cladding fails, thereby allowing steam/water to enter the fuel rod. The steam/water will react with the fuel to produce UO2+x thus releasing hydrogen, with x standing for the amount of interstitial oxygen ions above the stoichiometric value.
In this technical note the impact of fuel oxidation on fission gas release (FGR) is modeled and discussed. The classical diffusion equation is used to describe migration and release of fission product gas (Xe) in UO2+x under time-varying postirradiation annealing conditions. We assume that the main quantity affected by fuel oxidation is the effective diffusivity of fission gas. Fuel oxidation enhances the diffusivity as a function of x in UO2+x in a parabolic fashion for 0.005 ≤ x ≤ 0.12 in the temperature range of 1000 ≤ T ≤ 1600 K. We first benchmark our model against an annealing test in which for x = 0.004 the Xe release fraction was measured as a function of time (temperature) during annealing. Furthermore, we apply the model to simulate a series of postirradiation annealing tests on UO2+x fuel, in which FGR fractions were measured for a given thermal ramp history in the range 0.00 ≤ x ≤ 0.66. The results of our computations in the range 0.004 ≤ x ≤ 0.20 show good agreement with measurements.
