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1.Advanced power reactor design/2. Innovative computational methods
International networks/Advanced nuclear power plant technologies in Japan/ Textbooks

1.Advanced power reactor design
Design and analysis of advanced nuclear power plants such as supercritical-pressure light water cooled reactors (SCWR). The concept was devised in 1989 by us and developed since then. It was selected as a Generation 4 reactor in 2001. The international R&D is organized by the Generation 4 international forum of OECD/NEA in collaboration with IAEA. Our designs are called super light water reactor (Super LWR) and super fast reactor (Super FR) and lead the study in the world. "Nuclear power in 2030" (from The Japan Journal, December 2010 in English, January 2011 in Chinese)

The defining feature of the study is the coverage of major elements of reactor design and analysis. These elements include the fuel rod, the core, plant control system, startup schemes, stability, plant heat balance, safety systems and safety analyses. The differences in design and analysis of the Super LWR from light water reactor (LWR) are slight, but the studies require fundamental and essential understandings of reactor design and analysis. This knowledge will enhance in- depth knowledge of design and safety of LWRs and other reactor types.

The SCWR is new reactor type that was not constructed before. The optimum design is not known. The purpose of the design study of Super LWR and Super FR is to pursue optimum design of the supercritical-pressure light water cooled reactors. Pursuing "simplicity" is the principle of guiding the study. If the goal and the criteria are not met by the simplest design, it is slightly complicated and analyzed by computer simulation. Priorities of experimental R&D items are also determined from the quantitative evaluation of the effects on the reactor performance. This is a new and efficient way of reactor R&D.

Super FR is the fast reactor version with MOX (PuO2-UO2 mixed oxide) fuel. It has the same plant system as Super LWR. The once-through coolant cycle of the reactor is compatible with the tight fuel lattice core of the water cooled fast reactors.

In Japan, "Super fast reactor R&D" project was organized by us including experiments of thermal hydraulics, materials and its interactions with the coolant chemistry. The first phase in 2005-March 2010 was completed successfully. The second phase in August 2010-March 2013 is underway at Waseda University in collaboration with the professors and researchers of University of Tokyo, Kyushu University, Tohoku University, Japan Atomic Energy Agency (JAEA), TEPCO systems and National Institute of Advanced Science and Technology (AIST). The experimental results are common data base for the R&D of Super FR and Super LWR due to the same plant system.

Researches of power reactor studies and computational methods(PDF file)
Super FR project 1st phase (2005-2010)
Super FR project 2nd phase (2010-2013)

2. Innovative computational methods
Development of innovative computational methods such as MPS (moving particle semi-implicit) method for reactor analysis: MPS is the first particle method for analyzing incompressible medium such as water and solids. It was developed by professor Koshizuka, a co-worker in 1995. It is free from the problems of numerical diffusion and distortion of calculation meshes of the finite difference methods. Direct simulation of phase change, splashing, large deformation of solids, fluid-structure interactions are possible by MPS. Developments of MPS methods for analyzing molten core behaviors, boiling heat transfer problems, condensation behaviors are studied. The problems of nuclear reactors such as molten core behaviors are the subjects of the research, but the method is applied in many areas such as civil engineering, ocean engineering, medical problems and even physics based computer graphics.

The researches of Oka-laboratory cover major elements of nuclear reactor design and analysis, such as reactor physics, thermal hydraulics and reactor safety as well as radiation transport and its safety. Professor Oka has experiences of researches of broad subjects such as fast neutron transport and shielding, cross section sensitivity and uncertainty analyses, design of medical reactor for boron neutron capture therapy, fusion-fission hybrid reactors, fusion neutronics, nuclear data evaluation, reactor noise, probabilistic risk assessment etc. The experiences will be utilized for meeting the interests of researchers of Oka- laboratory in defining the subjects and finding the way of researches.

International networks
The researchers of Oka-laboratory take the advantage of the international networks of graduate students and researchers of past and present programs, projects and activities such as the international SCWR programs of Generation 4 international forum, leader of Super FR projects (first phase 2005- 2009 and 2nd phase 2010- 2012), as well as the world-wide human networks from the past international activities as the leader of Global COE program "nuclear education and research initiative" of University of Tokyo, the president of Atomic Energy Society of Japan, and the board member of ANS etc.
Internet TV conference systems are equipped in the lab and the department. On-line communication without travel and delay is possible.

Advanced nuclear power plant technologies in Japan
The nuclear power plant (NPP) is the biggest man- made products. It is the Japanese companies that developed advanced LWR technologies and constructed NPPs on schedule. Close collaboration with Japanese nuclear industries and research institutes are the features of JDNE and Oka-laboratory. Instruction of researches and education is given based on the advanced nuclear technologies.

Textbooks including the advanced nuclear technologies were prepared and published in the textbooks of "Nuclear engineering textbook series" of Ohm-sha. (English versions will be published.), "Super light water reactors and Super fast reactors" (Springer) and "Advances in light water reactor technologies" (Springer). The students of Oka-laboratory enjoy the advantages of the books that were written and edited by ourselves.

Study guide of Nuclear Engineering