著者

森 治嗣 手塚 健一 加賀見 雄一 手塚 英昭

出版者

一般社団法人日本機械学会

雑誌

年次大会講演論文集 : JSME annual meeting

巻号頁・発行日

vol.2003, no.3, pp.187-188, 2003-08-05

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Dry-out and rewetting on fuel rods in a reactor core, possibly observed during the events of pump trip or reactor power increase etc., are significant phenomena from the viewpoints of securing the integrity of a fuel rod and safety evaluation on MCPR in the design. The two-phase flow boiling visualization experiments of dry-out and rewetting processes by a high-speed digital movie were successfully carried out under BWR rated-operating condition of ∿7MPa and ∿286℃ in the present work; on the other hand, these visualization tests could be found only under the atmospheric pressure conditions so far. The tests were carried out using the thermal-hydraulic experimental loop of Tokyo Electric Power Co., Inc. (TEPCO), which enables us to directly observe the two-phase flow boiling, dry-out and rewetting phenomena under the BWR rated-operating conditions of ∿7MPa and ∿286℃. The observations by a high-speed digital movie, measurements of void fraction increase by optical-fiber void probes and rods' surface temperature soaring and steep diving by thermocouples brought us incontrovertible evidences of the occurrence of rewetting just after dry-out in transients.

著者

大森 修一 奈良林 直 森 治嗣 渡邉 史紀

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. B編 (ISSN:03875016)

巻号頁・発行日

vol.75, no.751, pp.403-405, 2009-03-25

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A Steam Injector (SI) is a simple, compact and passive pump. We are developing this innovative concept by applying the SI system for core injection system in emergency core cooling systems (ECCS) to further improve the safety of nuclear power plants. Passive ECCS in nuclear power plants would be inherently very safe and would prevent severe accidents by keeping the core covered with water (Severe accident-free concept). The passive core injection system (PCIS) driven by high-efficiency SI is a system that, in an accident such as a LOCA, attains a higher discharge pressure than the supply steam pressure used to inject water into the reactor by operating the SI. This report describes the experiments and the analytical simulation on a SI-driven PCIS for innovative-simplified nuclear power plant. In addition, we conducted the analytical simulations of SI, which grew in size for the actual nuclear power plant.