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Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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G7 pledges support for nuclear at Italy meeting
The Group of Seven (G7) recommitted its support for nuclear energy in the countries that opt to use it at a Ministerial Meeting on Climate in Italy last month.
In a statement following the April meeting, the group committed to support multilateral efforts to strengthen the resilience of nuclear supply chains, referencing the goal set by 25 countries during last year’s COP28 climate conference in Dubai to triple global nuclear generating capacity by 2050.
Per Seltborg, Jan Wallenius, Kamil Tucek, Waclaw Gudowski
Nuclear Science and Engineering | Volume 145 | Number 3 | November 2003 | Pages 390-399
Technical Paper | doi.org/10.13182/NSE03-A2390
Articles are hosted by Taylor and Francis Online.
In order to study the beam power amplification of an accelerator-driven system (ADS), a new parameter, the proton source efficiency * is introduced. * represents the average importance of the external proton source, relative to the average importance of the eigenmode production, and is closely related to the neutron source efficiency [varphi]*, which is frequently used in the ADS field. [varphi]* is commonly used in the physics of subcritical systems driven by any external source (spallation source, (d,d), (d,t), 252Cf spontaneous fissions, etc.). On the contrary, * has been defined in this paper exclusively for ADS studies where the system is driven by a spallation source. The main advantage with using * instead of [varphi]* for ADS is that the way of defining the external source is unique and that it is proportional to the core power divided by the proton beam power, independent of the neutron source distribution.Numerical simulations have been performed with the Monte Carlo code MCNPX in order to study * as a function of different design parameters. It was found that, in order to maximize * and therefore minimize the proton current needs, a target radius as small as possible should be chosen. For target radii smaller than ~30 cm, lead-bismuth is a better choice of coolant material than sodium, regarding the proton source efficiency, while for larger target radii the two materials are equally good. The optimal axial proton beam impact was found to be located ~20 cm above the core center. Varying the proton energy, */Ep was found to have a maximum for proton energies between 1200 and 1400 MeV. Increasing the americium content in the fuel decreases * considerably, in particular when the target radius is large.