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JAEA Reports

Multi-group diffusion perturbation calculation code PERKY; 2002

Iijima, Susumu; Okajima, Shigeaki

JAERI-Data/Code 2002-023, 44 Pages, 2002/12

JAERI-Data-Code-2002-023.pdf:1.6MB

no abstracts in English

JAEA Reports

A Study on Pore Structure of Compacted Bentonite (Kunigel-V1)

Sato, Haruo

JNC TN8400 99-064, 22 Pages, 1999/10

JNC-TN8400-99-064.pdf:1.45MB

Four kinds of diffusion experiments; (1)through-diffusion(T-D) experiments for compaction direction dependency, (2)in-diffusion(I-D) experiments for composition dependency of silica sand in bentonite, (3)I-D experiments for initial bentonite gain size dependency, and (4)I-D experiments for the restoration property of an artificial single fracture in compacted bentonite, were carried out using tritiated water which is a non-sorbing nuclide to evaluate the effect of pore structural factors for eompacted bentonite on diffudion. For(1), effective diffusivities (De) in Na-bentonites, Kunigel-V1 and Kunipia-F were measured for 1.0 and 1.5 Mgm $^{-3}$ . For(2), apparent diffusivities (Da) in Kunigel-V1 were measured for 0.8, 1.4 and 1.8 Mgm $^{-3}$ with silica sand of 30 and 50 wt%. For(3), Da values for 0.8, 1.4 and 1.8 Mgm $^{-3}$ were measured for a granulated Na-bentonite, OT-9607 which grain-size distribution is in a rang between 0.1 and 5 mm. For (4), Da values in Kunigel-V1 which a single fracture was artificially reproduced and was immersed in distilled water for 7 or 28 days for the restoration of the fracture, were measured for 1.8 Mgm $^{-3}$ . Although De values in Kunigel-V1 were approximately the same for both compacted directions over the density, De values for perpendicular direction to compacted direction were higher than those for the same direction as compacted direction in Kunipia-F. For composition dependency of silica sand in bentonite, no significant effect of the mixure of silica sand in bentonite on Da was found. For initial bentonite grain size dependency, Da values obtained for OT-960 were approximately the same as those for Kunigel-V1 and no effect of initial grain size of bentonite on diffusion was found. For the restoration property of a single fracture in compacted bentonite, no restoration period dependency on Da was found. Based on this, it may be said that diffusion of nuclides in compacted bentonite, ...

JAEA Reports

Fast Reactor Calculational Route for Pu Burning Core Design

Hunter

PNC TN9460 98-001, 156 Pages, 1998/01

PNC-TN9460-98-001.pdf:5.71MB

This document provides a description of a calculational route, used in the Reactor Physics Research Section for sensitivity studies and initial design optimization calculations for fast reactor cores. The main purpose in producing this document was to provide a description of and user guides to the calculational methods, in English, as an aid to any future user of the calculational route who is (like the author) handicapped by a lack of literacy in Japanese. The document also provides for all users a compilation of information on the various parts of the calculational route, all in a single reference. In using the calculational route (to model Pu burning reactors) the author identified a number of areas where an improvement in the modelling of the standard calculational route was warranted - the document includes a description of these changes. The calculational route makes use of several different computer programs. SLAROM calculates nuclear data from compositions, using either homogeneous or heterogeneous models. CITATION and MOSES do reactor burn-up and/or flux diffusion calculations; CITATION is used for 2D (RZ) calculations, whilst MOSES models 3D (hex-Z) geometry. PENCIL and CITDENS are essentially specialized versions of CITATION (PENCIL includes data preparation and other functions). MASSN calculates fuel cycle mass balances. PERKY performs perturbation and associated calculations, both 1'st order and exact perturbations. JOINT and RZOUT3 provide various dataset interface functions, including energy group condensation. Briefer descriptions of the calculational route are given, followed by a more detailed step-by-step approach to the calculations. This latter includes examples of all JCL and data files, and a description of all the data that a user may have to employ. The document does not give a complete description of the component programs: where options and/or data are not used in any of the calculations they have generally been ignored; ...

JAEA Reports

A Study on nuclide migration in buffer materials and rocks for geological disposal of radioactive waste

Sato, Haruo

PNC TN8410 97-202, 205 Pages, 1998/01

PNC-TN8410-97-202.pdf:14.14MB

This thesis summarizes the results investigated in order to establish a basic theory on the predictive method of diffusion coefficients of nuclides in compacted sodium bentonite which is a candidate buffer material and in representative rocks for the geological disposal of radioactive waste by measuring the pore structural factors of the compacted bentonite and rocks such as porosity and tortuosity, measuring diffusion coefficients of nuclides in the bentonite and rocks, acquiring basic data on diffusion and developing diffusion models which can quantitatively predict nuclide migration in long-term. This consists of 7 chapters. Chapter 1 is the introduction, in which conventional studies on nuclide migration in buffer materials and rocks for the geological disposal of radioactive waste carried out to date are reviewed, and those problems are summarized as well as the objectives of this study are described. Besides, the difinition of geological disposal is explained. In Chapter 2, it is described on non-steady state diffusion of HTO, Sr-90, Tc-99, I-129, Cs-137, Np-237, Am-241 and Pu in purified sodium bentonite, Kunipia-F, in which the rate of constituent Na-smectite was raised approximately 100wt%. In-diffusion experiments were carried out in a range of bentonite densities of 200 2000 kgm $^{-3}$ under ambient aerobic conditions at room temperature (20 23 $^{circ}$ C), and apparent diffusion coefficients (Da) were obtained. The apparent diffusion coefficients decreased with increasing dry density of bentonite. It was quantitatively indicated from diffusion experiments using HTO that these Da values include the effect of geometric retardation such as the tortuosity factor of compacted bentonite. It was experimentally clarified that Da is not affected by diffusion time based on diffusion experiments for different experimental periods using Sr and Cs. Moreover, it was also experimentally clarified that Da is not affected by tracer ...

Journal Articles

Boundary element method applied to neutron diffusion problems of a thin layer sandwiched between two zones

; C.A.Brebbia*

Boundary Elements XII, Vol.1; Applications in Stress Analysis, Potential and Diffusion, p.227 - 239, 1990/00

no abstracts in English

JAEA Reports

Study on analysis method for FBR cores (V)

Takeda, Toshikazu*; Ito, Noboru*; Kugo, Teruhiko*; Takamoto, Masanori*; Aoki, Shigeaki*; Kawagoe, Yoshihiro*; Sengoku, Katsuhisa*; Tanaka, Motonari*; Yoshimura, Akira*; Tamitani, Masashi*; et al.

PNC TJ2605 89-001, 251 Pages, 1989/03

PNC-TJ2605-89-001.pdf:4.46MB

no abstracts in English

JAEA Reports

Study on analysis method for FBR cores (III)

Takeda, Toshikazu*; Unesaki, Hironobu*; Nakano, Makoto*; Arakawa, Yasushi*; Sakuma, Hiroomi*; Kurisaka, Kenichi*; Ito, Noboru*; Oe, Takashi*; Yamaguchi, Yoshiharu*

PNC TJ2605 87-001, 204 Pages, 1987/03

PNC-TJ2605-87-001.pdf:3.82MB

no abstracts in English

JAEA Reports