Neutronics Integral Experiments of Lithium-Oxide Fusion Blanket with Heterogeneous Configurations Using Deuterium-Tritium Neutrons

Abstract

Neutronics experiments for two types of heterogeneous blankets are performed in the Phase-IIC experiments of the Japan Atomic Energy Research Institute/U.S. Department of Energy collaborative program on fusion blanket neutronics. The experimental system uses the same geometry as the previous Phase-IIA series, which was a closed geometry that used a neutron source enclosure of lithium carbonate. The heterogeneities selected for testing are the beryllium edge-on and the water coolant channel assemblies that appear in typical blankets. In the former, the beryllium and the lithium-oxide (Li₂O) layers are piled up alternately in the front part of the test blanket. In the latter, the two simulated water cooling channels are emplaced vertically in the Li₂O blanket. These channels produce a steep gradient of neutron flux and a significant spectrum change around the material boundary. The calculation accuracy and measurement method for these transient regions are key areas of interest in the experiments. The measurements are performed for the tritium production rate and the other nuclear parameters as well as the previous experiments. The void effect is found to not be negligible around the heterogeneous region for the detector with a low-energy response. At the same time, enhancements of tritium production are seen near the beryllium and hydrogenous material. However, the current Monte Carlo calculation shows good agreement with the experiment even in such a boundary.

Additional information

Notes on contributors

Yukio Oyama

Yukio Oyama (BS, physics, 1975; MS, nuclear physics, 1977; and Dr. Eng., 1989, Osaka University, Japan) is a principal scientist at the Japan Atomic Energy Research Institute (JAERI). He has worked in the area of fusion neutronics experiments since 1978. He is currently involved in intense and highenergy neutron source projects.

Chikara Konno

Chikara Konno (MS, physics, Kyoto University, Japan, 1985) is a research scientist in the Department of Reactor Engineering at JAERI. He has worked in the areas of fusion neutronics experiments, cross-section measurements, and neutron spectrum measurements using a proton-recoil counter.

Yujiro Ikeda

Yujiro Ikeda (PhD, nuclear engineering, Nagoya University, Japan, 1981) is head of the Fusion Neutronics Laboratory in the Department of Reactor Engineering at JAERI. He has worked in the areas of fusion neutronics experiments, induced radioactivity experiment and analysis, direct nuclear heating measurements, activation cross-section measurements, and fusion dosimetry.

Seiya Yamaguchi

Seiya Yamaguchi (BS, applied physics, Waseda University, Japan, 1980; MS, 1982, and PhD, 1989, energy sciences, Tokyo Institute of Technology, Japan) in 1982 joined the Department of Reactor Engineering at JAERI, where he engaged in research and development on the design and characterization of Li-glass scintillator for fusion neutronics application. From 1989, he was a research assistant with Photon Factory at KEK, National Laboratory for High Energy Physics, where he worked in the areas of microwave engineering for the electron linear accelerator.

Koichi Tsuda

Koichi Tsuda (BS, nuclear engineering, University of Tokyo, Japan, 1982) is a research scientist at JAERI. He has worked in the area of fusion neutronics experiments since 1982. He is especially involved in tritium measurement.

Kazuaki Kosako

Kazuaki Kosako (BE, atomic engineering, Tokai University, Japan, 1984) has worked at Sumitomo Atomic Energy Industries since 1994. He worked in the Department of Reactor Engineering at JAERI from 1984 to 1992 where he was involved mainly in fusion neutronics. He is currently interested in the area of radiation damage of materials.

Hiroshi Maekawa

Hiroshi Maekawa (BE, 1965; MS, 1967; and Dr. Eng., 1970, nuclear engineering, Tokyo Institute of Technology, Japan) is the deputy director of the Department of Reactor Engineering and the head of the Intense Neutron Source Laboratory at JAERI. He has worked on fusion neutronics for more than 20 years, and he planned and constructed the Fusion Neutronics Source (FNS) facility. He served as the Japanese leader of the JAERI/U.S. Department of Energy (U.S. DOE) collaboration on fusion blanket neutronics. His recent research has focused on International Fusion Materials Irradiation Facility conceptual design activities.

Masayuki Nakagawa

Masayuki Nakagawa (BS, 1965; MS, 1967; and PhD, 1979, nuclear engineering, Kyoto University, Japan) is a principal scientist in the Department of Reactor Engineering at JAERI. He is a head of the reactor system laboratory having the main responsibility for the computation method and design of reactors. He researched the development of neutronics computation methods and codes for fast reactors and fusion reactors and intelligent reactor design systems. His group has developed high-speed general-purpose Monte Carlo codes based on vector and/or parallel algorithms.

Takamasa Mori

Takamasa Mori (BS, 1976; MS, 1979; and PhD, 1985, nuclear engineering, Kyoto University, Japan) is a principal scientist in the Department of Reactor Engineering at JAERI. He worked for the development of neutron transport codes using double-differential from cross sections. His research interests are in the field of reactor physics, especially the speedup of Monte Carlo calculation of high-energy particles based on vector and/or parallel algorithms.

Tomoo Nakamura

Tomoo Nakamura (BS, physics, Kyoto University, Japan, 1957) is currently director of the Public Acceptance Database Center, Research Organization for Information Science and Technology. His research background includes experimental reactor physics on fast breeder reactors and nuclear technology on fusion reactor blankets. He served as the former Japanese leader of the JAERI/U.S. DOE collaboration on fusion blanket neutronics.

Mohamed A. Abdou

Mohamed A. Abdou is a professor in the Department of Mechanical, Aerospace, and Nuclear Engineering at the University of California, Los Angeles (UCLA) and also is the director of fusion technology at UCLA. His research interests include neutronics, thermomechanics, fusion technology, and reactor design and analysis. He served as the U.S. leader of the JAERI/U.S. DOE collaboration on fusion blanket neutronics.

Edgar F. Bennett

Edgar F. Bennett (PhD, University of New Hampshire, 1957) is a physicist at Argonne National Laboratory. He has been a section head of experimental reactor physics since 1970. He is best known as the inventor of a widely used in-core proton-recoil spectrometer –a technique that he has been continually updating. He has also made contributions to the field of reactivity measurement by reactor noise techniques, in particular, by providing a common theoretical basis and introducing a new type of variance experiment.

Anil Kumar

Anil Kumar (PhD, University of Bombay, India, 1981) is senior development engineer at UCLA. His current research interests include fusion reactor nucleonics experiments and analysis, technique development for nuclear heating, decay heat measurements, biological dose, fusion diagnostics, safety factor methodology for fusion reactor design parameters, low-activation materials, inertial confinement fusion, and sequential reactions. He has conducted experiments at leading facilities such as the FNS facility in Japan, the Tokamak Fusion Test Reactor (TFTR) at Princeton University, and LOTUS in Switzerland.

Mahmoud Z. Youssef

Mahmoud Z. Youssef (PhD, nuclear engineering, University of Wisconsin, 1980) is a senior research engineer in the Department of Mechanical, Aerospace, and Nuclear Engineering at UCLA. He participated in several conceptual magnetic fusion energy and inertial fusion energy reactor design studies with emphasis on nuclear analysis and blanket/shield design. His research interests are in the areas of blanket/shield design optimization, nuclear data, sensitivity/uncertainty studies, neutronics methods and code development, tritium fuel cycle, radioactivity and safety aspects of fusion, integral experiments, neutronics testing, and research and development for fusion reactors, particularly the International Thermonuclear Experimental Reactor (ITER).

Karl G. Porges

Karl G. Porges (PhD, University of California, Berkeley, 1952) is currently retired. He was a research physicist at ANL from 1958 through 1990. Areas of special interest to him include nuclear reactions, fission, neutron physics, nuclear reactor safety, mechanical and electronics instruments design, probability and stochastic theory, fluid mechanics, fusion blanket design, and tritium chemistry.