Utilization of research reactors for fundamental studies in university related activities in Japan

Transcription

1 Utilization of research reactors for fundamental studies in university related activities in Japan IAEA International Conference on Research Reactors Safe Managements and Effective Utilization Sydney, Australia, 5-9 November, 2007 Tatsuo Shikama Institute for Materials Research, Tohoku University Katahira, Aobaku, Sendai, Japan

2 The Oarai Branch( International Research Center for Nuclear Material Science), Institute for Materials Research, Tohoku University A facility placed in the Oarai Nuclear Conglomerate A Facility for utilizing research reactors sited in JAEA(Japan Atomic Energy Agency) -Oarai, namely, JMTR, JOYO, HTTR and JRR-3 in JAEA-Tokai A Facility open to university researchers for their fundamental studies utilizing reactors Operated by Institute for Materials Research of Tohoku University under close cooperation and collaboration with JAEA

3 A variety of research interests of university researchers, which should be coped with by the Oarai Branch Material Science Fundamental studies on radiation effects in materials Development of nuclear materials (Next generation fission reactors, fusion reactors) Reactor safety issues (degradation mechanism, evaluation of life time) Utilization of radiation effects on development of new materials Actinide science Nuclear Engineering and Technologies Back end technologies Radioactive analysis Geological and Cosmological Science Biological Science

4 A role as an effective interface between the reactor operating organization and users Regulatory Board Reactor operating organization Usually disinterest in motivations of individual researchers Keen to regulatory board Reluctant in bridging between regulatory issues and users demands Interface functions (effective utilization of RRs with appropriate safety) Users Variety of interests (cf. project type irradiation) Disinterest in regulatory and safe ty issues Usually unfamiliar with reactor technologies and related restrictions

5 Relationship among the Oarai Branch, university researchers, and research reactors mainly operated by JAEA

6 Oarai Nuclear Conglomerate JRR-3 Tokai area Reactor linkage NDC International collaboration NFD AGF JMTR HFIR (ORNL) BR-2 (MOL) Research collaboration with universities and education of post graduate students HTTR JMTR HL The Oarai Branch, IMR IMR as the international COE for materials research MMF FMF PIFs linkage JOYO

7 The Pacific Ocean Fast reactor JOYO JOYO-HLs Light water cooled JMTR JMTR-HL AGF High temperature Helium gas cooled HTTR The Oarai Branch, IMR Tohoku University Univ. HLs

8 Research reactors of JAEA JMTR Hot Laboratory Reactor Building Secondary pump Containment vessel Control room Dump heat exchanger Canal Reactor Pressure Vessel JOYO IHX Primary pump Oarai Research and development center Tokai site JRR-3 Intermediate heat exchanger Containment vessel HTTR Reactor pressure vessel

9 Research Reactors in Japan and World PHENIX Fast neutron flux (m 2 /s) JOYO KUR JRR-4 HBWR HFR HTTR JRR-3 JMTR HANARO OSIRIS HIFAR HFETR BR R2 NRU MIR-1R ATR Thermal Neutron Flux (m 2 /s) HFIR SM-3

10 Main activities of the Oarai Branch

11 History of development of irradiation capsules for university researches

12 High-accuracy Temperature Control System (Reactor irradiation being competent with advanced material science) Temp. Controller Vacuum Line Pool Guide Tube Gas Pressure RPV Capsule Temp. control Valve Power He gas Capsule Gas Gap Supply Vacuum Pump Core Heater T/C Sample Heater (Feedback Control) Reactor Power Signal Valve Quick Response by Computer Control Capsule Temp. Control System Computer

13 A Result of High-accuracy Temperature Control ( ) 300 Advanced Control ± Irradiation Temperature Manual Control Constant temperature control at reactor start up (JMTR) ±8 45MW 280 Reactor power 12 h 50MW (MW ) Reactor Power March,1, 14:00 Operating Time (h) March,3, 14:00 0

14 Irradiation parameters survey in single capsule (fluence and temperatures) Multi divided and multi temperature control rig for JMTR

15 In-situ Measurements Techniques Radiation Induced Conductivity (S/m) Electrical Properties of Ceramics as Insulator for Cable Dose Rate (Gy/s) Development Radiation-resistant Optical Fiber as New Instrument Optical Property Measurement of Diagnostic Windows for Fusion Reactor 1.8m 0.7m Optical Fiber Stepping Motor for Two-axis Drive Stepping Motor for Sample Change Micrometer Heater Ref.(R) KU2 Sapphire (S1) 300 ºC S2 400 ºC KU-Quarts (KU1) φ60mm Mo Corner Cubic Reflector

16 Irradiation rigs for measuring electrical conductivity and thermal conductivity in-situ in HFIR (Japan/USA collaboration JUPITER)

17 Optical Measurements with Radiation Resistant Optical Fibers Induced Loss (db/m) Irrad. source : Cobalt-60 gamma-ray Dose rate : 1.24e4 Gy/hr Fiber type : MF, fluorine doped core Manufacture : Mitsubishi Cable Co. 1.20E E E E E Wavelength (nm) Observed optical absorption of fluorine doped core fiber, type MF manufactured by Mitsubishi Co. Ltd., JPN - Absorption of visible wavelength range and NBOHC were increased with the exposure dose. - Radiation hardening effect was not appeared in the large exposure dose.

18 TRIST-Thermal conductivity measurement under JUPITER collaboration (USA/Japan Collaboration) ORNL CVI SiC/SiC 400 (In-plane) 700 (In-plane) 400 (In-plane,Oxidized) 400 (Crose-plane) 700 (Cross-plane) Elapsed Time(hrs) L 1 K = (G/)(L 22 -L 12 )/2(T 1-2 ) T 1 G : 核発熱 : 質量密度 L 2 G, ρ Heat-sink T 2 =const.

19 Irradiation tests of magnetic probe for ITER under Japan/USA/EU collaboration (JAEA/EU/Tohoku Univ./USA) coil capsule ~ 600 mm B A 15/11/02 20/11/02 25/11/02 30/11/02 5/12/02 10/12/02 15/12/ Sealed He atmosphere Fluence Monitor Steel caps Alumina bobbin 1500 I (na) DV (nv) Thermocouples Aluminium heatsink

20 In-cell equipment(desolution) Actinide research facility Oarai branch, Tohoku Uni. SQUID type magnetic fluxmeter Nuclear magnetic resonance spectrometer M1 M5 1 M2 M8 5 M4 M7 MgO 241 Am-MgO Fundamental studies on fuels and TransUranium elements Close collaboration with Oarai branch, Tohoku University in the area of actinide related study )

21 Concept of shroud for controlled and monitored irradiation in refurbished JMTR for fundamental studies of universities

22 Summing ups The Oarai Branch is planning to extend its activity of utilizing reactors around Oarai as well as overseas, under collaboration and cooperation with the JEAE. Refurbishing of JMTR More cooperative utilization of JOYO JRR-3 utilization on its easy access to its core region International collaboration with BR-2 in SCK/CEN, HFIR and it international materials irradiation center of ORNL. Its unique feature of advanced technology of microstructural analyses will be more emphasized to make a rigid basis for hot laboratory linkage around Oarai. Oarai COE for reactor irradiations The international collaboration will be essential for the future activity of the Oarai Branch. Effective utilization of limited sources Improvement of reliability of studies with research reactors