Criticality accident analysis in meltdown core

• Project/Area Number: 26630481
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Nuclear engineering
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Obara Toru 東京工業大学, 原子炉工学研究所, 教授 (40221858)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2015: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000); Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 福島第一原子力発電所事故 / 燃料デブリ / 臨界事故 / 放出エネルギー / 放射線量 / 東京電力福島第一原子力発電所 / 炉心溶融 / 廃炉

Outline of Final Research Achievements

This study aims to establish analysis method to estimate released energy and radiation dose in the case of criticality accident of meltdown core. It was shown that it is possible to perform kinetic analysis when there are some fuel debris regions in different condition in the core by the use of newly developed code. A method was established to estimate the increase of released energy and radiation dose when fuel debris exists around the fuel debris which becomes critical.

Research Products

• [Journal Article] Development of Transient Analysis Code for Estimation of Total Released Energy in a Two-Fuel-Solution-Tank System (2016)
  • Author(s): Haruka Kikuchi, Toru Obara
  • Journal Title: Annals of Nuclear Energy Volume: 87 Pages: 486-493
  • DOI: 10.1016/j.anucene.2015.09.027
  • Peer Reviewed
• [Journal Article] Fission Probability Density Functions for Kinetic Analysis in Weakly Coupled Fuel Debris (2015)
  • Author(s): Toru Obara, Delgersaikhan Tuya, Hiroki Takezawa
  • Journal Title: Transactions of the American Nuclear Society Volume: 113 Pages: 1150-1152
  • Peer Reviewed
• [Journal Article] Kinetic Analysis of Weakly Coupled Fuel Debris by Integral Kinetic Model (2015)
  • Author(s): Delgersaikhan Tuya, Toru Obara, Hiroki Takezawa
  • Journal Title: Transactions of the American Nuclear Society Volume: 113 Pages: 1158-1160
  • Peer Reviewed
• [Presentation] Statistical Uncertainty in Kinetic Analysis using Integral Kinetic Model for Re-criticality Accident in Weakly-Coupled Fuel Debris (2016)
  • Author(s): Delgersaikhan Tuya, Hiroki Takezawa, Toru Obara
  • Organizer: 日本原子力学会2016年春の年会
  • Place of Presentation: 東北大学川内キャンパス
  • Year and Date: 2016-03-26
• [Presentation] PROMPT SUPERCRITICAL KINETIC ANALYSIS WITH NEUTRON COUPLING BETWEEN FUEL DEBRIS (2015)
  • Author(s): Toru Obara, Hiroki Takezawa, Delgersaikhan Tuya
  • Organizer: International Conference on Nuclear Criticality Safety (ICNC2015)
  • Place of Presentation: Charlotte, North Carolina, USA
  • Year and Date: 2015-09-13
  • Int'l Joint Research
• [Presentation] Kinetic Analysis of Re-criticality Accident in Simplified System of Fuel Debris and Consolidated Fuel (2015)
  • Author(s): Delgersaikhan Tuya, Toru Obara
  • Organizer: 日本原子力学会2015年秋の大会
  • Place of Presentation: 静岡大学静岡キャンパス
  • Year and Date: 2015-09-09
• [Presentation] Application of Integral Kinetic Model to Transient Analysis of Different Types of Weakly Coupled Systems (2015)
  • Author(s): Delgersaikhan Tuya, Haruka Kikuchi, Toru Obara
  • Organizer: ICONE-23, 23th International Conference on Nuclear Engineering
  • Place of Presentation: Makuhari, Japan
  • Year and Date: 2015-05-17
  • Int'l Joint Research
• [Presentation] Fission Probability Density Functions for Super Prompt Criticality Accident Analysis in Weakly Coupled Systems by Integral Kinetic Model (2015)
  • Author(s): Toru Obara, Delgersaikhan Tuya, Haruka Kikuchi
  • Organizer: ICONE-23, 23th International Conference on Nuclear Engineering
  • Place of Presentation: Makuhari, Japan
  • Year and Date: 2015-05-17
  • Int'l Joint Research
• [Presentation] 積分型動特性モデルを用いた溶融デブリの臨界事故解析 (1)研究概要と解析手法 (2015)
  • Author(s): 小原徹、Delgersaikhan Tuya
  • Organizer: 日本原子力学会2015春の年会
  • Place of Presentation: 茨城大学
  • Year and Date: 2015-03-20 – 2015-03-22
• [Presentation] he Criticality Accident Analysis of Melted Debris by Integral Kinetic Model (2) Preliminary Analysis for Two-Unit Systems (2015)
  • Author(s): Delgersaikhan Tuya, Toru Obara
  • Organizer: 日本原子力学会2015春の年会
  • Place of Presentation: 茨城大学
  • Year and Date: 2015-03-20 – 2015-03-22
• [Remarks] 小原研究室ホームページ
  • URL: http://www.nr.titech.ac.jp/~tobara/index.html
• [Remarks] 小原研究室フェイスブックページ
  • URL: https://www.facebook.com/obaralab/