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Isogawa, Hiroki*; Naoi, Motomasa*; Yamasaki, Seiji*; Ho, H. Q.; Katayama, Kazunari*; Matsuura, Hideaki*; Fujimoto, Nozomu*; Ishitsuka, Etsuo
JAEA-Technology 2022-015, 18 Pages, 2022/07
As a summer holiday practical training 2021, the impact of 10 years long-term shutdown on critical control rod position of the HTTR and the delayed neutron fraction () of the VHTRC-1 core were investigated using Monte-Carlo MVP code. As a result, a long-term shutdown of 10 years caused the critical control rods of the HTTR to withdraw about 4.00.8 cm compared to 3.9 cm in the experiment. The change in critical control rods position of the HTTR is due to the change of some fission products such as Pu, Am, Pm, Sm, Gd. Regarding the calculation of the VHTRC-1 core, the value is underestimate of about 10% in comparison with the experiment value.
Hamamoto, Shimpei; Ishitsuka, Etsuo; Nakagawa, Shigeaki; Goto, Minoru; Matsuura, Hideaki*; Katayama, Kazunari*; Otsuka, Teppei*; Tobita, Kenji*
Proceedings of 2021 International Congress on Advances in Nuclear Power Plants (ICAPP 2021) (USB Flash Drive), 5 Pages, 2021/10
Impurity concentrations of hydrogen and hydride in the coolant were investigated in detail for the HTTR, a block type high-temperature gas reactor owned by Japan. As a result, it was found that CH was 1/10 of H concentration, which was under the conventional detection limit. If the ratio of H to CH in the coolant is the same as the ratio of HT to CHT, the CHT has a larger dose conversion factor, and this compositional ratio is an important finding for the optimal dose evaluation. Further investigation of the origin of CH suggested that CH was produced as a result of a thermal equilibrium reaction rather than being released as an impurity from the core.
Goto, Minoru; Okumura, Keisuke; Nakagawa, Shigeaki; Inaba, Yoshitomo; Matsuura, Hideaki*; Nakaya, Hiroyuki*; Katayama, Kazunari*
Fusion Engineering and Design, 136(Part A), p.357 - 361, 2018/11
Times Cited Count:6 Percentile:52.79(Nuclear Science & Technology)A High Temperature Gas-cooled Reactor (HTGR) is proposed as a tritium production device, which has the potential to produce a large amount of tritium using Li(n,)T reaction. In the HTGR design, generally, boron is loaded into the core as a burnable poison to suppress excess reactivity. In this study, lithium is loaded into the HTGR core instead of boron and is used as a burnable poison aiming to produce thermal energy and tritium simultaneously. The nuclear characteristics and the fuel temperature were calculated to confirm the feasibility of the lithium-loaded HTGR. It was shown that the calculation results satisfied the design requirements and hence the feasibility was confirmed for the lithium-loaded HTGR, which produce thermal energy and tritium.
Katayama, Kazunari*; Ushida, Hiroki*; Matsuura, Hideaki*; Fukada, Satoshi*; Goto, Minoru; Nakagawa, Shigeaki
Fusion Science and Technology, 68(3), p.662 - 668, 2015/10
Times Cited Count:16 Percentile:79.46(Nuclear Science & Technology)Tritium production utilizing nuclear reactions by neutron and lithium in a high-temperature gas-cooled reactor is attractive for development of a fusion reactor. From viewpoints of tritium safety and production efficiency, tritium confinement technique is an important issue. It is known that alumina has high resistance for gas permeation. In this study, hydrogen permeation experiments in commercial alumina tubes were conducted and hydrogen permeability, diffusivity and solubility was evaluated. By using obtained data, tritium permeation behavior from an AlO-coated Li-compound particle was simulated. Additionally, by using literature data for hydrogen behavior in zirconium, an effect of Zr incorporation into an AlO coating on tritium permeation was discussed. It was indicated that the majority of produced tritium was released through the AlO coating above 500C. However, it is expected that total tritium leak is suppressed to below 0.67% of total tritium produced at 500C by incorporating Zr fine particles into the inside of AlO coating.
Kawamoto, Yasuko*; Nakaya, Hiroyuki*; Matsuura, Hideaki*; Katayama, Kazunari*; Goto, Minoru; Nakagawa, Shigeaki
Fusion Science and Technology, 68(2), p.397 - 401, 2015/09
Times Cited Count:1 Percentile:9.74(Nuclear Science & Technology)To start up a fusion reactor, it is necessary to provide a sufficient amount of tritium from an external device. Herein, methods for supplying a fusion reactor with tritium are discussed. Use of a high temperature gas cooled reactor (HTGR) as a tritium production device has been proposed. So far, the analyses have been focused only on the operation in which fuel is periodically exchanged (batch) using the block type HTGR. In the pebble bed type HTGR, it is possible to design an operation that has no time loss for refueling. The pebble bed type HTGR (PBMR) and the block type HTGR (GTHTR300) are assumed as the calculation and comparison targets. Simulation is made using the continuous-energy Monte Carlo transport code MVPBURN. It is shown that the continuous operation using the pebble bed type HTGR has almost the same tritium productivity compared with the batch operation using the block type HGTR. The issues for pebble bed type HTGR as a tritium production device are discussed.
Nakaya, Hiroyuki*; Matsuura, Hideaki*; Katayama, Kazunari*; Goto, Minoru; Nakagawa, Shigeaki
Proceedings of 2015 International Congress on Advances in Nuclear Power Plants (ICAPP 2015) (CD-ROM), p.398 - 402, 2015/05
The performance of tritium production for fusion reactor using High-Temperature Gas-cooled Reactor (HTGR) is studied. An influence of Li concentration on tritium production performance using HTGR is estimated. Li compound is loaded in the reactor core using Li rod consisting cylindrical Li compound in cladding tube. A Gas Turbine High-Temperature Reactor of 300 MWe nominal capacity (GTHTR300) with 600 MW thermal output power is assumed as HTGR. An amount of tritium production is estimated by burn-up calculations using the continuous-energy Monte Carlo transport code MVP-BURN. The amount of tritium outflow is estimated from equilibrium solution for the tritium diffusion equation in the cladding tube. Even if 6Li is enriched, the GTHTR300 can produce 500 g of tritium over 180-day operation without increasing the amount of required Li. The amount of tritium outflow is decreased by 20-50%.
Mitsudo, Seitaro*; Hoshizuki, Hisanori*; Matsuura, Kazunari*; Saji, T.*; Idehara, Toshitaka*; Glyavin, M.*; Eremeev, A.*; Zapevalov, V.*; Kitano, Akihiro; Nishi, Hiroshi; et al.
Proceedings of 29th International Conference on Infrared and Millimeter Waves (IRMMW 2004)/12th International Conference on Terahertz Electronics (THz 2004), p.727 - 728 , 2004/09
Boron carbide (BC) is one of advanced materials and is being used in a wide rage of applications. The unique feature of this material is its large neutron-absorbing cross-section. Some of its most prominent applications are controlling rods in nuclear reactors and radiation protection. 24 GHz microwave processing for BC ceramics were performed under flowing argon gas using the sintering system. The sintered samples were characterized by the density, the shrinkage and SEM micrographs of fracture surface. Above the temperature of 2000C, the shrinkage and the grain grows were observed.
Goto, Minoru; Nakagawa, Shigeaki; Matsuura, Hideaki*; Nakaya, Hiroyuki*; Katayama, Kazunari*
no journal, ,
A high temperature gas-cooled reactor (HTGR) is proposed as a tritium production device, which can produce a large amount of tritium by loading coated Li pebbles into the core without a major change of the original reactor core design. The engineering study was performed to clarify the problem of the tritium production system and assess the possibility of the resolution. As a result, it was assessed that all of the problems could be resolved from an engineering view point by using the HTTR (High Temperature engineering Test Reactor) experiences on the production of the coated fuel particles and deal of the fuels.
Goto, Minoru; Nakagawa, Shigeaki; Matsuura, Hideaki*; Nakaya, Hiroyuki*; Katayama, Kazunari*
no journal, ,
The tritium fuel production system using a high-temperature gas-cooled reactor is proposed for initial fusion reactors. In this study, the feasibility assessment of the system was performed from the view point of engineering and safety.
Goto, Minoru; Okumura, Keisuke; Nakagawa, Shigeaki; Matsuura, Hideaki*; Nakaya, Hiroyuki*; Katayama, Kazunari*
no journal, ,
A feasibility study of a High Temperature Gas-cooled Reactor (HTGR) for tritium production using Li(n,)T reaction for fusion reactors has been conducted. In this study, the burn-up chain was modified to treat Li(n,a)T reaction directory in neutronics calculations, and then the feasibility study was performed from the view point of nuclear characteristics using SRAC code system, which has experience in neutronics analysis of HTGRs.
Nakaya, Hiroyuki*; Matsuura, Hideaki*; Kawamoto, Yasuko*; Nagasumi, Satoru*; Katayama, Kazunari*; Goto, Minoru; Nakagawa, Shigeaki
no journal, ,
We proposed the used of High Temperature Gas-cooled Reactors (HTGR) as a tritium production device, which produces tritium by Li(n,)T reaction, for initial fusion reactors. Concentrating of Li suppresses undesirable leakage of produced tritium into reactor coolant. In this study, the effect of Li concentration difference on the amount of the tritium leakage and the tritium production efficiency was investigated.
Goto, Minoru; Okumura, Keisuke; Nakagawa, Shigeaki; Inaba, Yoshitomo; Matsuura, Hideaki*; Nakaya, Hiroyuki*; Katayama, Kazunari*
no journal, ,
A feasibility study of a High Temperature Gas-cooled Reactor (HTGR) for tritium production using Li(n,)T reaction for fusion reactors has been conducted. In this study, the burn-up chain was modified to treat Li(n,)T reaction directory in neutronics calculations, and then the feasibility study was performed from the view point of nuclear and thermal characteristics using SRAC code system, which has experience in neutronics analysis of HTGRs.
Ida, Yuma*; Matsuura, Hideaki*; Nagasumi, Satoru*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki
no journal, ,
JAEA and Kyushu University have studied the tritium production method using high temperature gas-cooled reactors (HTGR) for initial fusion reactors. In this method, lithium compounds are loaded into the reactor core and tritium is produced with Li(n,)T reaction. We studied about optimization of lithium loading method, effective tritium containment method and nuclear thermal design of lithium loaded HTGR, and consequently we confirmed the feasibility of the tritium production method. Then, we started preliminary study for lithium irradiation experiment by test reactors. This paper describes evaluation results of tritium production and tritium containment for proposed lithium irradiation capsule.
Goto, Minoru; Nakagawa, Shigeaki; Matsuura, Hideaki*; Katayama, Kazunari*
no journal, ,
JAEA and Kyushu university have studied the tritium production method using high temperature gas-cooled reactors (HTGR) for initial fusion reactors. In this method, lithium compounds are loaded into the reactor core and tritium is produced with Li(n,)T reaction. We studied about the optimization of a lithium loading method, an effective tritium containment method and the nuclear thermal design of a lithium loaded HTGR, and consequently we confirmed the feasibility of the tritium production method. This paper describes the feasibility of the nuclear thermal design of the lithium loaded HTGR tritium production.
Matsuura, Hideaki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki
no journal, ,
JAEA and Kyushu University have studied the tritium production method using high temperature gas-cooled reactors (HTGR) for initial fusion reactors. In this method, lithium compounds are loaded into the reactor core and tritium is produced with Li(n,a)T reaction. We studied about the optimization of a lithium loading method, an effective tritium containment method and the nuclear thermal design of a lithium loaded HTGR, and consequently we confirmed the feasibility of the tritium production method. This paper describes the overview of the study.
Katayama, Kazunari*; Matsuura, Hideaki*; Otsuka, Teppei*; Fukada, Satoshi*; Goto, Minoru; Nakagawa, Shigeaki
no journal, ,
JAEA and Kyushu University have studied the tritium production method using high temperature gas-cooled reactors (HTGR) for initial fusion reactors. In this method, lithium compounds are loaded into the reactor core and tritium is produced with Li(n,a)T reaction. We studied about the optimization of a lithium loading method, an effective tritium containment method and the nuclear thermal design of a lithium loaded HTGR, and consequently we confirmed the feasibility of the tritium production method. This paper describes the results of the hydrogen permeation experiment and the results of the tritium permeation analysis based on the obtained data from the experiments.
Ida, Yuma*; Matsuura, Hideaki*; Nagasumi, Satoru*; Koga, Yuki*; Okamoto, Ryo*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo
no journal, ,
Tritium production method using HTGRs (High Temperature Gas-cooled reactors) is studied as the tritium supplying method for initial D-T fusion reactors. In this method, tritium is produced by Li (n,)T reaction. The amount of tritium production and the tritium confinement capability were evaluated in case of the irradiation capsule including the Li compound is installed into the HTGRs in the past. In this study, the tritium confinement capability is evaluated for the irradiation capsule with ZrC layer by performing calculations of the amount of tritium leakage. The calculation results showed that the amount of tritium leakage is decreased to one fifth with the ZrC layer.
Okamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru; et al.
no journal, ,
Currently, many researches to achieve DT nuclear-fusion power generation are under proceeding but the method to provide initial tritium loaded to fusion prototype reactor is not clear. The method of tritium production by using high temperature gas-cooled reactor (HTGR) was proposed. In this method, lithium rods are loaded to the reactor core of HTGR and tritium is produced by Li(n,)T reaction. And the method to reduce the spilled tritium by using the lithium rod with zirconium layer was proposed. In this study, the experiments to evaluate the performance of hydrogen absorption in the zirconium layer were conducted under the temperature condition more than 700C which is the normal operation condition for the very high temperature gas-cooled reactor (VHTR). The experimental result concerning solubility and diffusion factor of hydrogen in the zirconium layer will be presented and discussed.
Ida, Yuma*; Matsuura, Hideaki*; Nagasumi, Satoru; Okamoto, Ryo*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; et al.
no journal, ,
Large quantity of tritium is demanded for starting up of fusion reactor and engineering test using tritium for fusion blanket system. However, tritium is very rare and kg order of tritium must be produced artificially. Tritium production, by Li(n,)T reaction using the high temperature gas-cooled reactor (HTGR), has been proposed. In this method, loading of Li rods into burnable poison (BP) holes in HTGR is considered. In this paper, the Li rod suited to the demand for the utilization in High Temperature engineering Test Reactor (HTTR) is designed, and tritium production and leakage from Li-rod capsule are evaluated by adjusting the thickness of LiAlO, alumina, and Zr layers. A scenario of irradiation test supposed to be conducted at HTTR for demonstration of the tritium production and containment performance of the Li rod is presented.
Okamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Suganuma, Takuro*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; et al.
no journal, ,
It has been proposed that lithium rods, which are cylindrical lithium compounds, are loaded into a HTGR and tritium for initial fusion reactors is produced by Li(n,)T reaction. In this study, it was discussed that the lithium rods are covered with zirconium layers to prevent the produced tritium leak. The solubility and diffusion coefficient of hydrogen in zirconium were measured and the effectiveness of the zirconium layers on prevention of tritium leakage was estimated with the measured values. As a result, the tritium leakage ratio with the zirconium layers was estimated two orders lower than that without the zirconium layers, and hence it was considered that the zirconium layer is very effective on the prevention of the tritium leakage.