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Yamada, Fumiaki; Imaizumi, Yuya; Nishimura, Masahiro; Fukano, Yoshitaka; Arikawa, Mitsuhiro*
Proceedings of 25th International Conference on Nuclear Engineering (ICONE-25) (CD-ROM), 10 Pages, 2017/07
The loss-of-reactor-level (LORL) is one of the loss-of-heat-removal-system (LOHRS) of beyond-DBA (BDBA) severe accident. An evaluation method for the LORL which is caused by the coolant leakage in two positions of the primary heat transport system (PHTS) was developed for prototype JSFR which is loop-type sodium-cooled fast reactor. The secondary leakage in cold standby which occurred in different loop from that of the first leakage in rated power operation can lead LORL by excessive declining of the sodium level. Therefore, the sodium level behavior in RV was studied in a representative accident sequence by considering the sodium pumping up into RV, siphon-breaking to stop pumping out from RV and maintain the sodium level, and calculation programs for the transient sodium level in RV. The representative sequence with lowest sodium level was selected by considering combinations of possible leakage positions. As a result of the evaluation considering the countermeasures above, it was revealed that the LOHRS can be prevented by maintaining the sodium level for the operation of decay heat removal system, even in the leakages in two positions of PHTS which corresponds to BDBA.
Nakajima, Kunihisa
Mass Spectrometry (Internet), 5(2), p.S0055_1 - S0055_6, 2016/12
Though equilibrium vapor pressures are utilized to determine thermodynamic properties of not only gaseous species but also condensed phases, the obtained data often disagree by a factor of 100 and more. A new data analysis method is proposed using the so-called second and third law procedures to improve accuracy of vapor pressure measurements. It was found from examination of vapor pressures of cesium metaborate and silver that the analysis of the difference between the second and third law values can result in determination of an optimal data set. Since the new thermodynamic method does not require special techniques and or experiences in dealing with measured data, it is reliable and versatile to improve the accuracy of vapor pressure evaluation.
Utsumi, Takayuki*; Kimura, Hideo
JSME International Journal, Series B, 47(4), p.761 - 767, 2004/11
In this paper, we show that a new numerical method, the Constrained Interpolation Profile - Basis Set (CIP-BS) method, can solve partial differential equations (PDEs) with high accuracy and can be a universal solver by presenting examples for the solutions of typical parabolic, hyperbolic, and elliptic equations. Here, we present the numerical errors caused by this method, and illustrate that the solutions by the CIP-BS
method, in which fifth order polynomials are used to constrain the values and first and second order spatial derivatives, are highly refined compared to those by the CIP-BS
method, in which third order polynomials are used to constrain the values and first order spatial derivatives. The fact that this method can unambiguously solve PDEs with an one-to-one correspondence to analytical requirements is also shown for PDEs including singular functions like the Dirac delta function with Dirichet or Neumann boundary conditions. This method is straightforwardly applicable to PDEs describing complex physical and engineering problems.
Tobita, Masahiro*; Matsui, Yoshinori
JAERI-Tech 2003-042, 132 Pages, 2003/03
JAERI-Tech-2003-042.pdf:7.19MB
Prediction of irradiation temperature is one of the important issues in the design of the capsule for irradiation test. Many kinds of capsules with complex structure have been designed for recent irradiation requests, and three-dimensional (3D) temperature calculation becomes inevitable for the evaluation of irradiation temperature. For such 3D calculation, however, many works are usually needed for input data preparation, and a lot of time and resources are necessary for parametric studies in the design. To improve such situation, JAERI introduced 3D-FEM (finite element method) code NISA (Numerically Integrated elements for System Analysis) and developed several subprograms, which enabled to support input preparation works in the capsule design. The 3D temperature calculation of the capsule are able to carried out in much easier way by the help of the subprograms, and specific features in the irradiation tests such as non-uniform gamma heating in the capsule, becomes to be considered.
Shibata, Keiichi
JAERI-Data/Code 2002-026, 516 Pages, 2003/01
JAERI-Data-Code-2002-026-Part1.pdf:25.12MBJAERI-Data-Code-2002-026-Part2.pdf:28.24MB
The third revision of JENDL-3 (JENDL-3.3) was released in 2002. The library contains evaluated neutron nuclear data for 337 nuclides. This report presents a brief description of the evaluation method which is given in the MF1 part of JENDL-3.3.
Nakajima, Ken; Yamamoto, Toshihiro; Miyoshi, Yoshinori
Journal of Nuclear Science and Technology, 39(11), p.1162 - 1168, 2002/11
Times Cited Count：8 Percentile：47.85(Nuclear Science & Technology)A modified quasi-steady-state method has been developed to evaluate the mean power during a nuclear excursion in fissile solution. The original method used the critical equation based on the one-group theory to calculate the reactivity. However, the one-group approximation reduces the calculation accuracy and the geometrical buckling used in the critical equation is not applicable to complex geometries. Then, we have modified the method to use the feedback coefficients of reactivity. Although the modified method requires an external calculation to obtain the feedback coefficients, it is applicable to complex geometries and gives more accurate results than the one-group approximation. Moreover, a new method to calculate the boiling power has been developed. using the experimental data of a supercritical experiment facility, SILENE. Experimental analyses were conducted to validate the new method for supercritical xperiments using CRAC and TRACY. The results showed good agreements with the experiments.
Ishihara, Masahiro; Baba, Shinichi; Takahashi, Tsuneo*; Aihara, Jun; Shibata, Taiju; Hoshiya, Taiji
JAERI-Tech 2002-054, 169 Pages, 2002/07
JAERI-Tech-2002-054.pdf:5.93MB
no abstracts in English
Tobita, Masahiro*; Matsui, Yoshinori
KAERI/GP-195/2002, p.87 - 95, 2002/00
In the Japan Materials Testing Reactor (JMTR) of Japan Atomic Energy Research Institute (JAERI), the temperature distribution inside of irradiation specimens and capsules structure material are evaluated in the design of irradiation capsules. For the evaluation of detailed temperature distribution, NISA (Numerically Integrated elements for System Analysis) code has been introduced, and subprograms are developed to simplify the input data of the capsules structure and the analysis conditions using the three-dimensional finite element method. By the development of subprograms, prediction of the temperature distribution inside of irradiation specimens and capsules structure material became detailed and more accurate than calculation by one-dimensional code. Also estimation of detail temperature distribution during irradiation became possible based on the indication of thermocouple.
Tokuda, Shinji
Purazuma, Kaku Yugo Gakkai-Shi, 77(3), p.276 - 283, 2001/03
no abstracts in English
Asano, Yoshihiro
JAERI-Research 99-045, 105 Pages, 1999/08
JAERI-Research-99-045.pdf:3.56MB
no abstracts in English
Nakajima, Ken; ;
Proceedings of 6th International Conference on Nuclear Criticality Safety (ICNC '99), 3, p.1286 - 1292, 1999/00
no abstracts in English
Shibata, Keiichi;
JAERI-Data/Code 98-006, 959 Pages, 1998/02
JAERI-Data-Code-98-006-Part1.pdf:21.14MBJAERI-Data-Code-98-006-Part2.pdf:20.28MB
no abstracts in English
Takemiya, Hiroshi*; Higuchi, Kenji; *
Modeling and Simulation Based Engineering, p.497 - 502, 1998/00
no abstracts in English
Fukahori, Tokio; Mukaiyama, Takehiko; Oyama, Yukio; Chiba, Satoshi; Takada, Hiroshi; Maekawa, Hiroshi; Shibata, Tokushi*; Nakamura, Takashi*; *; *; et al.
Nihon Genshiryoku Gakkai-Shi, 40(1), p.3 - 28, 1998/00
Times Cited Count：1 Percentile：11.76(Nuclear Science & Technology)no abstracts in English
Takemiya, Hiroshi*; *; *
JAERI-Data/Code 96-010, 52 Pages, 1996/03
JAERI-Data-Code-96-010.pdf:2.28MB
no abstracts in English
JAERI-Review 96-002, 30 Pages, 1996/01
JAERI-Review-96-002.pdf:2.11MB
no abstracts in English
Yokokawa, Mitsuo;
Joho Shori Gakkai Kenkyu Hokoku, 93(33), p.37 - 44, 1993/04
no abstracts in English
Araya, Fumimasa; *; *; ;
Proc. of the Joint Int. Conf. on Mathematical Methods and Supercomputing in Nuclear Applications,Vol. 1, p.466 - 476, 1993/00
no abstracts in English
Araya, Fumimasa; *; *;
Doryoku, Enerugi Gijutsu No Saizensen : Shimpojiumu Koen Rombunshu 1992, p.225 - 230, 1992/00
no abstracts in English
Nishimura, Hideo
Dai-12-Kai Kaku Busshitsu Kanri Gakkai Nenji Taikai Rombunshu, p.72 - 79, 1991/06
no abstracts in English
