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Kuramochi, Masaya*; Yamamoto, Kazami; Kinsho, Michikazu
JAERI-Tech 2003-055, 148 Pages, 2003/07
The injection beam dump of the 3 GeV rapid cycling synchrotron (3 GeV-RCS) is to be installed to absorb the H and H beams that can not be changed into H beam with a graphite foil. We estimate the maximum temperature and thermal stress of the injection beam dump. As a result, the temperature at the center region made of iron reached up to 370 K after several operation cycles (one cycle is three-week operation including one-week interval) under the 1kW-beam injection. Then, the temperature at the boundary between the iron region of the beam dump and the concrete wall of the tunnel was rather low temperature of about 320 K. And the maximum Mises stresses of 96 MPa and about 0.2 MPa were generated in the iron region and the concrete wall respectively. These values were much lower than the allowable temperature and stresses.
Yanagi, Yoshihiko*; Sato, Satoshi; Enoeda, Mikio; Hatano, Toshihisa; Kikuchi, Shigeto*; Kuroda, Toshimasa*; Kosaku, Yasuo; Ohara, Yoshihiro
Journal of Nuclear Science and Technology, 38(11), p.1014 - 1018, 2001/11
Times Cited Count:24 Percentile:83.19(Nuclear Science & Technology)no abstracts in English
; Kuroda, Toshimasa*; Enoeda, Mikio
JAERI-Tech 98-059, 75 Pages, 1999/01
no abstracts in English
; Yamaguchi, Akira
PNC TN9410 98-028, 33 Pages, 1997/12
The safety analysis of FBR plant system for sodium leak phenomena needs to evaluate the deposition of the aerosol particle to the components in the plant, the chemical reaction of aerosol to humidity in the air and the effect of the combustion heat through aerosol to the structural component. For this purpose, ABC-INTG (Aerosol Behavior in Containment-INTeGrated Version) code has been developed and used until now. This code calculates aerosol behavior in the gas area of uniform temperature and pressure by 1 cell-model. Later, however, more detailed calculation of aerosol behavior requires the installation of aerosol model into multi-cell thermal hydraulic analysis code AQUA. AQUA can calculate the carrier gas flow, temperature and the distribution of the aerosol spatial concentration. On the other hand, ABC-INTG can calculate the generation, deposition to the wall and flower, agglomeration of aerosol particle and figure out the distribution of the aerosol particle size. Thus, the combination of these two codes enables to deal with aerosol model coupling the distribution of the aerosol spatial concentration and that of the aerosol particle size. AQUA and ABC-INTG were developed separately, therefore, several subroutine were modified and composed. Especially, the interface program which exchanges data between these two codes is important to execute transient calculation. This report describes aerosol behavior model, how to install the aerosol model to AQUA and new subroutine equipped to the code. Furthermore, the test calculations of the simple structural model were executed by this code, appropriate results were obtained. Thus, this code has prospect to predict aerosol behavior by the introduction of coupling analysis with multi-dimensional gas thermo-dynamics for sodium combustion evaluation.
PNC TN9410 97-039, 187 Pages, 1997/05
A numerical evaluation system, which is consisted of four codes, AQUA, DINUS-3, THEMIS and BEMSET has been developed for thermal striping phenomena. To validate the system for the phenomena, thermally fluid - structure interaction analysis was carried out using a existing sodium experiment of parallel impinging jet simulating the outlet region of an LMFBR core. Calculational results on the RMS values of temperature fluctuation, the histograms of temperature amplitudes and frequencies, the auto-power spectral density distributions of temperature fluctuations and the damping characteristics of temperature fluctuations showed good agreement with the measured values under the test conditions of various flow velocity. From the comparisons with the experimental data, it was concluded that the numerical evaluation system is applicable to the evaluation of thermally fluid - structure interaction phenomena related to the thermal striping.
Ushigusa, Kenkichi; Mori, Katsuharu*; ; Nagashima, Keisuke; ; ; Aoyagi, Tetsuo; Takahashi, Yoshikazu; Matsui, Kunihiro; Kikuchi, Mitsuru; et al.
JAERI-Research 97-027, 281 Pages, 1997/03
no abstracts in English
PNC TN9420 96-057, 48 Pages, 1996/09
New type of numerical scheme CIP has been proposed for solving hyperbolic type equations and the CIP is focused on as a less numerical diffusive scheme. C-CUP method with the CIP scheme is adopted to numerical simulations that treat compressible and incompressible fluids, phase change phenomena and Mixture fluids. To evaluate applicabilities of the CIP scheme and C-CUP method for thermal hydraulic analyses related to Fast Breeder Reactors (FBRs), the scheme and the method were reviewed. Feature of the CIP scheme and procedure of the C-CUP method were presented. The CIP scheme is used to solve linear hyperbolic type equations for advection term in basic equations of fluids. Key issues of the scheme is that profile between grid points is described to solve the equation by cubic polynomial and spatial derivatives of the polynomial. The scheme can capture steep change of solution and suppress numerical error. In the C-CUP method, the basic equations of fluids are divided into advection terms and the other terms. The advection terms is solved with CIP scheme and the other terms is solved with difference method.The C-CUP method is robust for numerical instability, but mass of fluid will be in unfair preservation with non-conservative equations for fluids. Numerical analyses with the CIP scheme and the C-CUP method has been performed for phase change, mixture and moving object. These analyses are depend on characteristics of that the scheme and the method are robust for steep change of density and useful for interface tracking.
Otsuka, Hideo; ; Shimada, Taihei
JAERI-M 93-051, 37 Pages, 1993/03
no abstracts in English
Ohno, Shuji;
PNC TN9410 92-370, 54 Pages, 1992/11
Conputational code SOFIRE-M3 has been developed to evaluate the thermal consequences which would be brought by the sodium columnar leak and fire accident postulated in the FBRs. New code is the improved version of SOFIRE-MII and has following features. (1)Sodium columnar combustion rate is calculated from the empirical formula which has been derived from the results of Run-E3 test series and has the terms of sodium leak rate, leak height, and oxygen concentration in the atmosphere. (2)Calculational parameters of heat distribution fraction, which determine the reaction heat transferred to both sodium and gas, have been optimized by the post-test calculations of Run-E3 using the SOFIRE-M3 code. The code predicts heat transfer phenomena within 30% of accuracy when the optimized parameters are used. Calculations of large-scale sodium leak and fire tests Run-E2 and Run-D2, which had been performed at the SAPFIRE facility in 1985 and 1986 respectively, showed good agreement between code calculated and measured data. This SOFIRE-M3 code can contribute in the near future to the more optimized designing and safety evaluation of FBR p1ant. Refinement of the empirical formula and improvement of the code remain as future subjects related to the effect of sodium leak rate on the columnar combustion rate.
Muramatsu, Toshiharu
PNC TN9410 90-147, 115 Pages, 1990/10
In-vessel thermohydraulics analysis was conducted for transient simulating a pump coast down and reactor scram (manual reactor trip event) to evaluate effects of an inner barrel on a large fast breeder reactor. Then four thermohydraulics phenomena, a thermal stratification, a main loop temperature transient, a circumferential temperature distribution and a sodium surface velocity were discussed. Through the analysis using the multi-dimensional code AQUA and the discussion, the following have been effects of the inner barrel as obtained: [Thermal Stratification] This phenomenon is not influenced very much on presence of an inner barrel. And appearance of an axial temperature distribution can be neglected from a structural design. [Main Loop Temperature Transient] An inner barrel is required. Because a cold shock with maximum temperature transient -2.0C/s occurred at a outlet nozzle when an inner barrel was not equipped. [Circumferential Temperature Distribution] This phenomenon is not influenced very much on presence of an inner barrel. And appearance of the temperature distribution can be neglected from a structural design. But further investigation on a thermal stress at reactor vessel is necessary. [Sodium Surface velocity] An inner barrel is unnecessary. From the above results, it is concluded that an inner barrel is unnecessary if the cold shock is improved by a increase of effective mixing region on a design.
Muramatsu, Toshiharu
PNC TN9410 90-146, 64 Pages, 1990/10
In vessel thermohydraulic analysis for coolant mixing characteristics of the MONJU lower plenum was carried out by multi-dimensional thermohydraulic analysis code AQUA. The characteristics comes up as an important problem when thermocouples located above the core utilized for a experimantally evalution of the MONJU in-vessel thermohydraulics. From the analysis, the following results have becn obtained: [Forced Convection Condition] (1)Coolant in the lower plenum was mixed efficiently bv a swiring flow effects. Therefore circumferential temperature distribution normalized by totally temperature difference at the high pressure plenum inlet region decreased to 20% from 50%. (2)In forced convetion condition, a buoyancy effect is smaller than inertia by the swirling flow effect. [Natural Convection Condition] Coolant mixing by the swirling flow cannot be expected due to increasing buoyancy effects. Therefore delicate cares on circumferential temperature distribution are necessary for in-vessel thermohydraulic evaluations.
; Nakamura, H.
JAERI-M 83-220, 27 Pages, 1983/12
no abstracts in English