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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
I. Otic, G. Grötzbach
Nuclear Science and Engineering | Volume 155 | Number 3 | March 2007 | Pages 489-496
Technical Paper | Mathematics and Computation, Supercomputing, Reactor Physics and Nuclear and Biological Applications | doi.org/10.13182/NSE07-A2679
Articles are hosted by Taylor and Francis Online.
Results of a direct numerical simulation (DNS) for Rayleigh-Bénard convection for the Rayleigh number Ra = 105 in a fluid with the Prandtl number Pr = 0.025, which corresponds to liquid lead-bismuth, are used to analyze the turbulent heat flux and the temperature variance dissipation rate. The results indicate that application of a thermal or a mixed timescale may considerably improve gradient diffusion and algebraic heat flux models at these Rayleigh and Prandtl numbers. Therefore, a good approximation of the temperature variance dissipation rate is required. The standard temperature variance dissipation rate model is investigated using the DNS results. The analysis of the standard model shows the importance of wall functions and qualitatively good predictions by the model for this type of flow. Quantitatively, the model overpredicts the temperature variance dissipation rate evaluated from the results of DNS by ~25%. The two-point correlation method is used to derive new models for the temperature variance dissipation rate. Comparison with DNS results shows qualitatively and quantitatively good predictions by the new models. These new models lead therefore to an increased accuracy of the turbulent heat flux models for this type of flow.