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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.
Hiroshi Nakashima, Shun-Ichi Tanaka, Tomoo Suzuki
Fusion Science and Technology | Volume 16 | Number 3 | November 1989 | Pages 365-376
Technical Paper | Shielding | doi.org/10.13182/FST89-A29127
Articles are hosted by Taylor and Francis Online.
An experiment was carried out to study the behavior of 14-MeV neutrons incident to a large cavity composed of mortar coated with stainless steel, which simulates a neutral beam injector (NBI) in a tokamak fusion reactor. Fast neutron spectra and reaction rate distributions were measured inside the cavity with a 5.06-cm-high × 5.06-cm-diam NE-213 spectrometer as well as 232Th and 235U fission counters. The experimental results were analyzed with a Monte Carlo MCNP-3 code, using nuclear data files from the JENDL series and from ENDF/B-IV. Calculations with two discrete ordinates codes, DOT3.5 and BERMUDA-2DN, using ENDF/B-IV and JENDL nuclear data files, were also compared with the measurements to study their applicability for NBI design. For fast neutrons, the MCNP calculations are in good agreement with the measurements. Moreover, comparison between the DOT3.5 and BERMUDA-2DN calculations showed the significant effect of the Legendre expansion of neutron scattering in the high-energy region. For low-energy neutrons, the DOT3.5 code calculations agreed with the measurements, while the MCNP code could not successfully reproduce the measurements. The experiments also suggested that the ratios of thermal and epithermal neutrons were constant for the 14-MeV neutrons coming into the cavity.