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Division Spotlight
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.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
Standards Program
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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Latest News
Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Yukio Ishiguro, Keisuke Okumura
Nuclear Technology | Volume 84 | Number 3 | March 1989 | Pages 331-343
Technical Paper | Probabilistic Safety Assessment and Risk Management / Fission Reactor | doi.org/10.13182/NT89-A34217
Articles are hosted by Taylor and Francis Online.
A new concept is proposed for a high conversion light water reactor (HCL WR) that achieves both high conversion and high burnup while maintaining a negative void reactivity coefficient. This HCLWR has a flat “pancake” core with thick axial blankets. By using the flat core, a potential problem of HCLWRs, the positive void reactivity coefficient, can be reduced by neutron leakage, and a fuel assembly of very tight lattice pitch can be used. The leakage neutrons are utilized in the axial blankets to enhance the conversion ratio. With the axial blankets, the core shows a small value for the axial power peaking factor, and the plutonium enrichment can be largely reduced by the neutron reflection, including the fast fission due to 238U, compared with the bare core. Moreover, upgraded burnup characteristics can be obtained by the accumulation of fissile plutonium in the blankets. The flat core with the blankets can be applied to a small- or intermediate-scale light water reactor. The analysis combines a cell burnup calculation and a one-dimensional burnup calculation based on the diffusion method. The evaluation method of the void coefficient is validated for the flat core with axial blankets under practical, controlled conditions. Moreover, the accuracy of the present method is validated for the transport effect on the major physics parameters of interest by using the one-dimensional transport code ANISN and the Monte Carlo code VIM.