Investigation of water-vapor two-phase flow characteristics in a tight-lattice core by large-scale numerical simulation, 4; Large-scale analysis of water-vapor two-phase flow in rod bundles with TPFIT code using earth simulator

Yoshida, Hiroyuki; Ose, Yasuo*; Kureta, Masatoshi*; Nagayoshi, Takuji*; Takase, Kazuyuki; Akimoto, Hajime

Nihon Genshiryoku Gakkai Wabun Rombunshi, 4(2), p.106 - 114, 2005/06

https://doi.org/10.3327/taesj2002.4.106

no abstracts in English

Investigation of water-vapor two-phase flow characteristics in a tight-lattice core by large-scale numerical simulation, 3; Analysis of liquid film falling down on inclined flat plate

Yoshida, Hiroyuki; Nagayoshi, Takuji*; Ose, Yasuo*; Takase, Kazuyuki; Akimoto, Hajime

Nihon Genshiryoku Gakkai Wabun Rombunshi, 4(1), p.25 - 31, 2005/03

https://doi.org/10.3327/taesj2002.4.25

no abstracts in English

Development of a large-scale numerical simulation method on water-vapor two-phase flow through light-water reactor cores

Yoshida, Hiroyuki; Ose, Yasuo*; Takase, Kazuyuki; Akimoto, Hajime

Proceedings of 4th Japan-Korea Symposium on Nuclear Thermal Hydraulics and Safety (NTHAS-4), p.270 - 276, 2004/12

no abstracts in English

Pressure drop characteristics in tight-lattice bundles for reduced-moderation water reactors

Tamai, Hidesada; Kureta, Masatoshi; Yoshida, Hiroyuki; Akimoto, Hajime

JSME International Journal, Series B, 47(2), p.293 - 298, 2004/05

no abstracts in English

Large-scale numerical simulations of two-phase flow behavior in a fuel bundle of a reduced-moderation light water reactor

Takase, Kazuyuki; Yoshida, Hiroyuki; Ose, Yasuo*; Tamai, Hidesada; Kano, Takuma; Akimoto, Hajime

Nihon Konsoryu Gakkai Nenkai Koenkai 2003 Koen Rombunshu, p.33 - 34, 2003/00

no abstracts in English

Design of small Reduced-Moderation Water Reactor (RMWR) with natural circulation cooling

Okubo, Tsutomu; Suzuki, Motoe; Iwamura, Takamichi; Takeda, Renzo*; Moriya, Kumiaki*; Kanno, Minoru*

Proceedings of International Conference on the New Frontiers of Nuclear Technology; Reactor Physics, Safety and High-Performance Computing (PHYSOR 2002) (CD-ROM), 10 Pages, 2002/10

A small scale around 300 MWe reduced-moderation water reactor (RMWR) concept has been developed. For the core, a BWR type core concept with the tight-lattice fuel rod arrangement and the high void fraction is adopted to attain a high conversion ratio over 1.0. The negative void reactivity coefficients are also required, and the very flat short core concept is adopted to make the natural circulation cooling (NC) possible. The core burn-up of 60 GWd/t and the operation cycle of 24 months are also attained. For the system, simplification of the system with the passive safety features is a basic approach to overcome the scale demerit as well as the NC. For example, the HPCF system is replaced with the passive accumulator system resulting in the expensive emergency DGs reduction. The cost evaluation for concerned NSSS components gives about 20% reduction. Since MOX fuels in the RMWR contains Pu around 30 wt% and is irradiated to a high burn-up, the fuel safety evaluation has been performed and the acceptable results have been obtained from the thermal feasibility point of view.

Core and system design of Reduced-Moderation Water Reactor with passive safety features

Iwamura, Takamichi; Okubo, Tsutomu; Yonomoto, Taisuke; Takeda, Renzo*; Moriya, Kumiaki*; Kanno, Minoru*

Proceedings of International Congress on Advanced Nuclear Power Plants (ICAPP) (CD-ROM), 8 Pages, 2002/00

Research and developments of reduced-moderation water reactor (RMWR) have been performed. The RMWR can attain the favorable characteristics such as high burn-up, long operation cycle, multiple recycling of plutonium and effective utilization of uranium resources, based on the matured LWR technologies. MOX fuel assemblies in the tight-lattice fuel rod arrangement are used to reduce the moderation of neutron, and hence, to increase the conversion ratio. The conceptual design has been accomplished for the small 330MWe RMWR core with the discharge burn-up of 60GWd/t and the operation cycle of 24 months, under the natural circulation cooling of the core. A breeding ratio of 1.01 and the negative void reactivity coefficient are simultaneously realized in the design. In the plant system design, the passive safety features are intended to be utilized mainly to improve the economy. At present, a hybrid one under the combination of the passive and the active components, and a fully passive one are proposed. The former has been evaluated to reduce the cost for the reactor components.

Study on reduced-moderation water reactor (RMWR) core design; Joint research report, FY1998-1999 (Joint research)

Research Group for Advanced Reactor System; Research Group for Reactor Physics; Research Group for Thermal and Fluid Engineering

JAERI-Research 2000-035, 316 Pages, 2000/09

JAERI-Research-2000-035.pdf:19.81MB

no abstracts in English

Safety analyses of a high conversion LWR with BWR type tight lattice core

Okubo, Tsutomu; Tomiai, Ichio*; Osugi, Toshitaka

JAERI-M 93-015, 72 Pages, 1993/02

JAERI-M-93-015.pdf:1.64MB

no abstracts in English