Description of passive safety systems

The isolation condenser will be utilized for the 330 MW(e) RMWR, which is basically the same as the conventional one and is, therefore, not described in here. The passive containment cooling system (PCCS) with horizontal heat exchangers will be utilized for the large-size RMWR, details of which are described in the section for the ABWR-II in this report.

Item

Unit

Design value

Electric power output

MW(e)

330

Core circumscribed radius

M

2.07

Core average burn-up

GWd/t

60

Core effective height

M

1.3

Core exit quality

%

52

Core void fraction

%

69

Core pressure drop

MPa

0.04

Enrichment of reload fuel at equilibrium core

%

18

Conversion ratio

1.01

Max. power density

kW/m

42

MCPR

1.3

Void reactivity coefficient

10-

-0.5

Fuel cycle length

month

24

image081

FIG. VIII-4. Schematic of axial core configuration for the
330 MW(e) RMWR.

image082

FIG. VIII-5. Plant system concept for the 330 MW(e) RMWR.

Research and development (R&D) activities for the RMWR have been conducted by the JAERI in collaboration with the Japanese industries, which have clarified the favourable characteristics of the reactor including high conversion ratio of more than one, high burn-up, long operation cycle, and multiple recycling of plutonium. So far, the R&D has been conducted under several domestic frameworks, including a) the research corporation program between the Japan Atomic Power Company (JAPC) and JAERI where many RMWR systems were studied, b) the innovative and viable nuclear energy technology (IVNET) development project where the 330 MW(e) RMWR was developed with JAPC, Hitachi Ltd. and Tokyo Institute of Technology (IWAMURA, T., 2002), c) the program sponsored by the ministry of education, culture, sports, science and technology (MEXT) on the innovative nuclear reactor technologies where the bundle core heat transfer tests are conducted together with broad ranges of R&D for fuel and neutronics (OHNUKI, A., 2004, KURETA, M., 2004, YOSHIDA, H., 2004), and d) the feasibility study on the commercialized fast reactor cycle systems conducted by the Japan nuclear cycle development institute. In addition to the above domestic frameworks, the JAERI entered into the agreement with the USDOE on the tight lattice core design in December, 2004.

REFERENCES TO ANNEX VIII

[1] IWAMURA, T., et al., Core and System Design of Reduced-Moderation Water Reactor with Passive Safety Features, Proc. of ICAPP ’02-220 Int. Cong. On Advan. Nucl. Pow. Plants, Florida, USA (2002) (CD-ROM) 8page.

[2] KURETA, M. et al., Development of Predictable Technology for Thermal/Hydraulic

Performance of Reduced-Moderation Water Reactors (2) — Large — scale Thermal/Hydraulic Test

and Model Experiments, ICAPP’04, 4056 Pittsburgh, USA (2004).

[3] OHNUKI, A. et al., Development of Predictable Technology for Thermal/Hydraulic

Performance of Reduced-Moderation Water Reactors (1) — Master Plan, ICAPP’04, 4055 Pittsburgh, USA (2004).

[4] INTERNATIONAL ATOMIC ENERGY AGENCY, Status of advanced light water reactor designs 2004, IAEA-TECDOC-1391 (2004), pp.418-435.

[5] YOSHIDA, H. et al., Development of Predictable Technology for Thermal/Hydraulic

Performance of Reduced-Moderation Water Reactors (3) — Current Status of Development of Three-Dimensional Two-Phase Flow Simulation Method, ICAPP’04, 4057 Pittsburgh, USA (2004).