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Journal Articles

HTTR-GT/H$$_{2}$$ test plant; System performance evaluation for HTTR gas turbine cogeneration plant

Sato, Hiroyuki; Nomoto, Yasunobu*; Horii, Shoichi*; Sumita, Junya; Yan, X.

Nuclear Engineering and Design, 329, p.247 - 254, 2018/04

 Times Cited Count:2 Percentile:53.66(Nuclear Science & Technology)

This paper presents the system performance evaluation for HTTR gas turbine cogeneration test plant (HTTR-GT/H$$_{2}$$ plant) so as to confirm that the design meets the requirements with respect to the demonstration test objective. Start-up and shut down operation sequences as well as operability of load following operation were investigated. In addition, system dynamic and control analyses for the test plant in the events of loss of generator load and upset of H$$_{2}$$ plant were performed. The simulation results presented in the paper show that the test plant is suitable for the test bed to validate control schemes against postulated transients in the GTHTR300C. The results also lead us to the conclusion that HTTR-GT/H$$_{2}$$ plant can be used to test operational procedures unique to HTGR direct-cycle gas turbine cogeneration.

Journal Articles

Design of HTTR-GT/H$$_{2}$$ test plant

Yan, X. L.; Sato, Hiroyuki; Sumita, Junya; Nomoto, Yasunobu*; Horii, Shoichi*; Imai, Yoshiyuki; Kasahara, Seiji; Suzuki, Koichi*; Iwatsuki, Jin; Terada, Atsuhiko; et al.

Nuclear Engineering and Design, 329, p.223 - 233, 2018/04

 Times Cited Count:6 Percentile:14.73(Nuclear Science & Technology)

The pre-licensing design of an HTGR cogeneration test plant to be coupled to JAEA's existing test reactor HTTR is presented. The plant is designed to demonstrate the system of JAEA commercial plant design GTHTR300C. With construction planned to be completed around 2025, the test plant is expected to be the first-of-a-kind nuclear system operating on two of the advanced energy conversion systems attractive for the HTGR closed cycle helium gas turbine for power generation and thermochemical iodine-sulfur water-splitting process for hydrogen production.

JAEA Reports

Investigation and measures of abnormal events of helium refrigerator for cryogenic hydrogen system at J-PARC

Aso, Tomokazu; Teshigawara, Makoto; Hasegawa, Shoichi; Aoyagi, Katsuhiro*; Muto, Hideki*; Nomura, Kazutaka*; Takada, Hiroshi; Ikeda, Yujiro

JAEA-Technology 2017-021, 75 Pages, 2017/08


Liquid hydrogen is employed as a cold neutron moderator material at the spallation neutron source of Materials and Life science experimental Facility of Japan Proton Accelerator Research Complex (J-PARC). From January 2015, it became observable that the differential pressure between heat exchangers and an 80 K adsorber (ADS) in a helium refrigerator system increased with operating time. In November 2015, the differential pressure rise became more significant, leading to degrade the refrigerating performance in cooling liquid hydrogen. In order to investigate the cause of the abnormal differential pressure rise between the heat exchangers and the ADS, we carried out visual inspection inside the heat exchangers and analyzed the impurities contained in the helium gas. Unfortunately, we could not identify the impurities causing the performance degradation, but observed a trace of oil in the inlet piping of the heat exchanger. Based on investigations of the abnormal events occurred in the refrigerators with similar refrigerating capacity at other facilities, we took measures that cleaning the heat exchangers with Freon and replacing the ADS with new one. As a result, the differential pressure rise phenomenon was removed to recover the performance. We have detected oil from the Freon used for cleaning the heat exchangers and at a felt supporting charcoal packed in the ADS. In particular, oil was accumulated in membranous form onto the felt at the entrance side in the ADS. The amount of oil contained in the helium gas was about 10 ppb or so, less than the design value, in the helium refrigerator. However, the oil accumulated onto the felt in the ADS through long operating period may cause abnormal differential pressure rise, leading to the performance degradation of the helium refrigerator. Further study is needed to specify the cause more clearly.

JAEA Reports

Design database of helium gas turbine for HTTR-GT/H$$_{2}$$ test plant (Revised version)

Imai, Yoshiyuki; Sato, Hiroyuki; Yan, X.

JAEA-Data/Code 2017-011, 39 Pages, 2017/08


This report is the revised version of the report titled "Design Database of Helium Gas Turbine for High Temperature Gas-cooled Reactor, JAEA-Data/Code 2016-007" reflecting component design and experimental data analysis results for fission product isotope diffusion through the turbine blade alloy conducted in Fiscal Year 2016.

Journal Articles

Field test of a full scale $$^{3}$$He-alternative HLNC-type counter; High Level Neutron counter-Boron (HLNB)

Henzlova, D.*; Menlove, H. O.*; Tanigawa, Masafumi; Mukai, Yasunobu; Nakamura, Hironobu

EUR-28795-EN (Internet), p.313 - 323, 2017/00

Facing the depletion of $$^{3}$$He gas supply and the continuing uncertainty of options for future resupply, Los Alamos National Laboratory (LANL) designed and built a $$^{3}$$He free full scale thermal neutron coincidence counter based on boron-lined parallel-plate proportional technology. The counter was designed as a direct alternative to High Level Neutron Coincidence counter (HLNC-II). This paper provides a summary of performance evaluation of HLNB under realistic field conditions at Plutonium Conversion Development Facility (PCDF) of Japan Atomic Energy Agency (JAEA). The field test included a range of small to large mass MOX materials that represent realistic process samples and provided key insight on and validation of the feasibility of HLNB as a safeguards instrument in realistic facility environment. In particular, the results of verification measurements demonstrate that HLNB is capable to satisfy ITV expected for HLNC-II-type counter of 2.1% in 300s measurement time.

JAEA Reports

Design database of helium gas turbine for high temperature gas-cooled reactor

Imai, Yoshiyuki; Sato, Hiroyuki; Nomoto, Yasunobu; Yan, X.

JAEA-Data/Code 2016-007, 27 Pages, 2016/08


This report provides design database for helium gas turbine for HTGR. The design details for secondary helium cooling system and helium gas turbine in a heat application system to be coupled to the HTTR are described. In addition, experimental data for fission product isotope diffusion through turbine blade alloy is compiled.

Journal Articles

HTTR demonstration program for nuclear cogeneration of hydrogen and electricity

Sato, Hiroyuki; Yan, X.; Sumita, Junya; Terada, Atsuhiko; Tachibana, Yukio

Journal of Nuclear Engineering and Radiation Science, 2(3), p.031010_1 - 031010_6, 2016/07

This paper explains the outline of HTTR demonstration program with a plant concept of the heat application system directed at establishing an HTGR cogeneration system with 950$$^{circ}$$C reactor outlet temperature for production of power and hydrogen as recommended by the task force. Commercial deployment strategy including a development plan for the helium gas turbine is also presented.

Journal Articles

Thermal mixing behavior in the annulus of co-axial double-walled piping in HTGR

Tochio, Daisuke; Fujiwara, Yusuke; Ono, Masato; Shinohara, Masanori; Hamamoto, Shimpei; Iigaki, Kazuhiko; Takada, Shoji

Proceedings of 24th International Conference on Nuclear Engineering (ICONE-24) (DVD-ROM), 9 Pages, 2016/06

From the HTTR operational experience, it is needed to clear the thermal mixing characteristics of the helium gas at the annulus of the co-axial double-walled piping in HTGR. In this paper, thermal-hydraulic analysis on the helium gas at the annular flow path of the co-axial double pipe with T-junction was conducted. The analysis was performed under the condition of the different annular flow path height and with the different flow rate of the higher- and the lower-temperature helium gas. It is shown that the thermal mixing behavior is not so much affected by the flow rate of higher- and lower-temperature helium gas, and it is difficult to mix the helium gas with the smaller height of the annular flow path. It is confirmed that it is difficult to mix the helium gas in the annular flow path of the co-axial double-walled piping by using the hydraulic behavior, and it is necessary to arrange the mixing promotor in the annular flow path.

Journal Articles

Development of sample assay system equipped with $$^{3}$$He Alternative Neutron Detectors (ASAS), 1; Design and fabrication of ASAS detector

Ozu, Akira; Tobita, Hiroshi; Kureta, Masatoshi; Tanigawa, Masafumi; Mukai, Yasunobu; Nakamichi, Hideo; Nakamura, Hironobu; Kurita, Tsutomu; Seya, Michio

Kaku Busshitsu Kanri Gakkai (INMM) Nippon Shibu Dai-36-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2015/12

Against the background of the serious shortage of $$^{3}$$He gas, the Japan Atomic Energy Agency (JAEA) has newly developed an alternative ZnS ceramic scintillation neutron detector for the safeguards, with the support of the government (MEXT). A demonstrator of plutonium inventory sample assay system (ASAS) has been also developed as an alternative HLNCC (High Level Neutron Coincidence Counter). The results from numerical simulations using Monte-Carlo code MCNPX showed that the fundamental performances of ASAS equipped with the 24 alternative neutron detectors, such as neutron detection efficiency and die-away time, equal to or higher than those of conventional HLNCC could be obtained. Here we present the inner mechanical structure of ASAS, together with the results of the simulating design.

Journal Articles

Effect of helium on irradiation creep behavior of B-doped F82H irradiated in HFIR

Ando, Masami; Nozawa, Takashi; Hirose, Takanori; Tanigawa, Hiroyasu; Wakai, Eiichi; Stoller, R. E.*; Myers, J.*

Fusion Science and Technology, 68(3), p.648 - 651, 2015/10

 Times Cited Count:1 Percentile:86.11(Nuclear Science & Technology)

Pressurized tubes of F82H and B-doped F82H irradiated at 573 and 673 K up to $$sim$$6dpa have been measured by a laser profilometer. The irradiation creep strain in F82H irradiated at 573 and 673 K was almost linearly dependent on the effective stress level for stresses below 260 MPa and 170 MPa, respectively. The creep strain of $$^{10}$$BN-F82H was similar to that of F82H IEA at each effective stress level except 294 MPa at 573 K irradiation. For 673 K irradiation, the creep strain of some $$^{10}$$BN-F82H tubes was larger than that of F82H tubes. It is suggested that a swelling caused in each $$^{10}$$BN-F82H because small helium babbles might be produced by a reaction of $$^{10}$$B(n, $$alpha$$) $$^{7}$$Li.

Journal Articles

Numerical evaluation of the light transport properties of alternative He-3 neutron detectors using ceramic scintillators

Ozu, Akira; Takase, Misao*; Haruyama, Mitsuo; Kurata, Noritaka*; Kobayashi, Nozomi*; Kureta, Masatoshi; Nakamura, Tatsuya; To, Kentaro; Sakasai, Kaoru; Suzuki, Hiroyuki; et al.

Nuclear Instruments and Methods in Physics Research A, 798, p.62 - 69, 2015/10

 Times Cited Count:2 Percentile:74.03(Instruments & Instrumentation)

The light transport properties of scintillator light inside alternative He-3 neutron detector modules using scintillator sheets have been investigated by a ray-tracing simulation code. The detector module consists of a light-reflecting tube, a thin rectangular ceramic scintillator sheet laminated on a glass plate, and two photo-multiplier tubes (PMTs) mounted at both ends of the detector tube. The light induced on the surface of the scintillator sheet via nuclear interaction between the scintillator and neutrons are detected by the two PMTs. The light output of various detector modules in which the scintillator sheets are installed with several different arrangements were examined and evaluated in comparison with experimental results. The results derived from the simulation reveal that the light transport property is strongly dependent on the arrangement of the scintillator sheet inside the tube and the shape of the tube.

JAEA Reports

Maintenance of helium refrigerator/liquefier system in ITER CS Model Coil Test Facility

Ebisawa, Noboru; Kiuchi, Shigeki*; Kikuchi, Katsumi*; Kawano, Katsumi; Isono, Takaaki

JAEA-Testing 2014-003, 37 Pages, 2015/03


Objective of the ITER CS Model Coil Test Facility is to evaluate a large scale superconducting conductor for fusion using the Central Solenoid (CS) Model Coil, which can generate a 13-T magnetic field in the inner bore with a 1.5m diameter. The facility is composed of a helium refrigerator / liquefier system, a DC power supply system, a vacuum system and a data acquisition system. This report describes that maintenance of the helium refrigerator / liquefier system since the Great East Japan Earthquake in March 2011 until the first operation after the earthquake in December 2012.

Journal Articles

Basic technology development of advanced non-destructive detection / Measurement of nuclear material for nuclear security and nuclear nonproliferation

Seya, Michio; Naoi, Yosuke; Kobayashi, Naoki; Nakamura, Takahisa; Hajima, Ryoichi; Soyama, Kazuhiko; Kureta, Masatoshi; Nakamura, Hironobu; Harada, Hideo

Kaku Busshitsu Kanri Gakkai (INMM) Nippon Shibu Dai-35-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2015/01

The Integrated Support Center for Nuclear Non-proliferation and Nuclear Security (ISCN) of Japan Atomic Energy Agency (JAEA) has been conducting (based on collaborations with JAEA other centers) the following basic technology development programs of advanced non-destructive detection/measurement of nuclear material for nuclear security and nuclear non-proliferation. (1) The demonstration test of the Pu-NDA system for spent fuel assembly using PNAR and SINRD (JAEA/USDOE(LANL) collaboration, completed in JFY2013), (2) Basic development of NDA technologies using laser Compton scattered $$gamma$$-rays (Demonstration of an intense mono-energetic $$gamma$$-ray source), (3) Development of alternative to He-3 neutron detection technology, (4) Development of neutron resonance densitometry (JAEA/JRC collaboration)This paper introduces above programs.

Journal Articles

Evaluation of light transport property in alternative He-3 neutron detectors using ceramic scintillators by a ray-tracing simulation

Ozu, Akira; Takase, Misao*; Kurata, Noritaka*; Kobayashi, Nozomi*; Tobita, Hiroshi; Haruyama, Mitsuo; Kureta, Masatoshi; Nakamura, Tatsuya; Suzuki, Hiroyuki; To, Kentaro; et al.

Proceedings of 2014 IEEE Nuclear Science Symposium and Medical Imaging Conference; 21st International Symposium on Room-Temperature Semiconductor X-ray and $$gamma$$-ray detectors (NSS/MIC 2014), 5 Pages, 2014/00

In Japan Atomic Energy Agency, the helium-3 alternative neutron detector using ceramic scintillators for nuclear safeguards is under development with the support of the government. The alternative detector module consists of four components: an aluminum regular square tube, a light reflecting foil put on the inner surface of the square tube, a rectangular scintillator sheet sintered on a glass plate, and two PMTs provided at both ends of the tube. The scintillator sheet is fit on the diagonal inside the square tube. The light transport property of scintillator lights inside the tube influences on the fundamental performance of the alternative detector. Therefore, the properties of the lights emitted on the surface of the scintillator sheet and scintillation lights passing through the glass plate to the PMTs in several arrangements of the scintillator in the tubes were investigated with a ray-tracing simulation. The results are described in comparison with the experimental results.

Journal Articles

Blister formation in rutile TiO$$_{2}$$(100) films by helium irradiation

Yamamoto, Shunya; Nagata, Shinji*; Takeyama, Akinori; Yoshikawa, Masahito

Nuclear Instruments and Methods in Physics Research B, 249(1-2), p.374 - 376, 2006/08

 Times Cited Count:8 Percentile:50.36(Instruments & Instrumentation)

no abstracts in English

Journal Articles

Design result of the cryogenic hydrogen circulation system for 1 MW pulse spallation neutron source (JSNS) in J-PARC

Aso, Tomokazu; Tatsumoto, Hideki; Hasegawa, Shoichi; Ushijima, Isamu*; Otsu, Kiichi*; Kato, Takashi; Ikeda, Yujiro

AIP Conference Proceedings 823, p.763 - 770, 2006/05

no abstracts in English

Journal Articles

Radiation hardening and -embrittlement due to He production in F82H steel irradiated at 250 $$^{circ}$$C in JMTR

Wakai, Eiichi; Jitsukawa, Shiro; Tomita, Hideki*; Furuya, Kazuyuki; Sato, Michitaka*; Oka, Keiichiro*; Tanaka, Teruyuki*; Takada, Fumiki; Yamamoto, Toshio*; Kato, Yoshiaki; et al.

Journal of Nuclear Materials, 343(1-3), p.285 - 296, 2005/08

 Times Cited Count:38 Percentile:6.98(Materials Science, Multidisciplinary)

The dependence of helium production on radiation-hardening and -embrittlement has been examined in a reduced-activation martensitic F82H steel doped with $$^{10}$$B, $$^{11}$$B and $$^{10}$$B+$$^{11}$$B irradiated at 250$$^{circ}$$C to 2.2 dpa. The total amounts of doping boron were about 60 massppm. The range of He concentration produced in the specimens was from about 5 to about 300 appm. Tensile and fracture toughness tests were performed after neutron irradiation. 50 MeV-He$$^{2+}$$ irradiation was also performed to implant about 85 appm He atoms at 120$$^{circ}$$C by AVF cyclotron to 0.03 dpa, and small punch testing was performed to obtain DBTT. Radiation-hardening of the neutron-irradiated specimens increased slightly with increasing He production. The 100 MPam$$^{1/2}$$ DBTT for the F82H+$$^{11}$$B, F82H+$$^{10}$$B+$$^{11}$$B, and F82H+$$^{10}$$B were 40, 110, and 155$$^{circ}$$C, respectively. The shifts of DBTT due to He production were evaluated as about 70$$^{circ}$$C by 150 appmHe and 115$$^{circ}$$C by 300 appmHe. The DBTT shift in the small punch testing was evaluated as 50$$^{circ}$$C.

Journal Articles

Gas release of SiC implanted with deuterium or helium

Aihara, Jun; Sawa, Kazuhiro; Furuya, Yoshio*; Hojo, Tomohiro*; Furuno, Shigemi*; Yamamoto, Hiroyuki; Hojo, Kiichi; Ishihara, Masahiro

Journal of the American Ceramic Society, 88(8), p.2319 - 2321, 2005/08

 Times Cited Count:0 Percentile:100(Materials Science, Ceramics)

no abstracts in English

Journal Articles

Interlinked test results for fusion fuel processing and blanket tritium recovery systems using cryogenic molecular sieve bed

Yamanishi, Toshihiko; Hayashi, Takumi; Kawamura, Yoshinori; Iwai, Yasunori; Isobe, Kanetsugu; Uzawa, Masayuki*; Nishi, Masataka

Fusion Science and Technology, 48(1), p.63 - 66, 2005/07

 Times Cited Count:6 Percentile:56.28(Nuclear Science & Technology)

no abstracts in English

JAEA Reports

Study of high efficiency excited helium atom beam production for electric field measurements with high spatial and temporal resolution by laser-induced fluorescence method, JAERI's nuclear research promotion program, H13-013 (Contract research)

Yoshikawa, Kiyoshi*; Takiyama, Ken*; Onishi, Masami*; Yamamoto, Yasushi*; Nagasaki, Kazunobu*; Masuda, Kai*; Toku, Hisayuki*; Horiike, Hiroshi*

JAERI-Tech 2005-006, 116 Pages, 2005/03


no abstracts in English

363 (Records 1-20 displayed on this page)