Applications of ultrasound technique to flow velocity measurement in water experiment of inter-wrapper flow; Comparison with particle image velocimetry

Kimura, Nobuyuki; ; ; ; Kamide, Hideki; Tokuhiro, Akira; Hishida, Koichi

JNC TN9400 2000-057, 60 Pages, 2000/05

JNC-TN9400-2000-057.pdf:2.11MB

ln experimental study for the thermohydraulics of fast reactor, a simple experiment with fine measurement has been desired for understanding of phenomena and for verification of computer code rather than mockup experiments of large scale. For such purposes quality of experimental data must be improved. ln the velocity measurement, instantaneous velocity profile will have great advances for the understanding of phenomena and for the verification of computer code. ln this report two methods of the velocity profile measurement are discussed; one is ultrasound Doppler velocimetry (UDV) and the other is particle image velocimetry (PIV). These methods were applied to water experiments. The UDV was applied to pipe flow, planer jet, and the inter-wrapper flow which is seen in the gap region between subassemblies of fast reactor core. Cross check with laser Doppler velocimetly showed proper measurement of the UDV. Problems including the application to sodium experiments are also discussed. The PIV was also applied to the inter-wrapper flow. For the application to complex flow geometry, noise reduction method was developed to improve the measurement accuracy.

Current status and future plan for thermaI striping investigations at JNC

; kasahara, Naoto; ; ; Kamide, Hideki

JNC TN9400 2000-010, 168 Pages, 2000/02

JNC-TN9400-2000-010.pdf:8.78MB

Thermal striping is significant issue of the structural integrity, where the hot and cold fluids give high cycle fatigue to the structure through the thermal stress resulted from the time change of temperatur distibution in the structure. In the sodium cooled fast reactor, temperature change in fluid easily transfers to the structure because of the high thermal conductivity of the sodium. It means that we have to take care of thermal striping, The thermal striping is complex phenomena between the fluid and structure engineering fields. The investigations of thermal striping are not enough to evaluate the integrity directly. That is the fluctuation intensity at the structure surface is assumed to be temperature difference between source fluids (upstream to the mixing region) as the maximum value in the design. 0therwise, the design conditions are defined by using a mockup experiment and large margin of temperature fluctuation intensity. Furthermore, such evaluation manners have not yet been considered as a design rule. Transfer mechanism of temperature fluctuation from fluid to structure has been investigated by the authors on the view points of the fluid and structure. Attenuation of temperature fluctuation was recognized as a dominant factor of thermal fatigue. We have devdoped a numerical analysis system which can evaluate thermal fatigue and crack growth with consideration of the attenuation of temperature fluctuation in fluid, heat transfer, and structure. This system was applied to a real reactor and the applicability was confirmed. Further verification is planned to generalize the system. For the higher cost performance of the fast reactor, an evaluation rule is needed, which can estimate thermal loading with attenuation and can be applied to the design. An idea of the rule is proposed here. Two methods should be prepared; one is a precise evaluation method where mechanism of attenuation is modeled, and the other is simple evaluation method where ...

A study on in-situ measuring method of an unsaturated zone

Nishida, Kaoru*; Maemura, Tsuneyuki*

JNC TJ7400 2000-004, 102 Pages, 2000/02

JNC-TJ7400-2000-004.pdf:5.64MB

no abstracts in English

Compilation of Kinetic Data for Geochemical Calculations

Arthur, R. C,*; Savage, D.*; Sasamoto, Hiroshi; Shibata, Masahiro; Yui, Mikazu

JNC TN8400 2000-005, 61 Pages, 2000/01

JNC-TN8400-2000-005.pdf:2.83MB

Kinetic data, including rate constants, reaction orders and activation energies, are compiled for 34 hydrolysis reactions involving feldspars, sheet silicates, zeolites, oxides, pyroxenes and amphiboles, and for similar reactions involving calcite and pyrite. The data are compatible with a rate law consistent with surface reaction control and transition-state theoly, which is incorporated in the geochemieal software package EQ3/6 and GWB. Kinetic data for the reactions noted above are strictly compatible with the transition-state rate law only under far-from-equilibrium conditions. It is possiblethat the data are conceptually consistent with this rate law under both far-from-equilibrium and near-to-equilibrium conditions, but this should be confirmed whenever possible through analysis of original experimental results, Due to limitations in the availability of kinetic data for mineral-water reactions, and in order to simplify evaluations of geochemical models of groundwater evolution, it is convenient to assume local-equilibrium in such models whenever possible. To assess whether this assumption is reasonable, a modeling approach accounting for coupled fluid flow and water-rock interaction is described that can be used to estimate spatial and temporal scale of local equiliblium. The approach is demonstrated for conditions involving groundwater flow in fractures at JNC's Kamaishi in-situ tests site, and is also used to estimate the travel time necessary for oxidizing surface waters to migrate to the level of a HLW repository in crystalline rock. The question of whether local equilibrium is a reasonable assumption must be addressed using an appropriate modeling approach. To be appropriate for conditions at the Kamaishi site using the modeling approach noted above, the fracture fill must closely approximate a porous medium, groundwater flow must be purely advective and diffusion of solutes across the fracture-host rock boundary must not occur. Moreover, the ...

Discrete Fracture Network Code Development; Heisei-10 progress report

Dershowitz, W.*; Doe, T.*; Shuttle, D.*; Eiben, T.*; Fox, A.*; Emsley, S.*; Ahlstrom, E.*

JNC TJ1400 99-012, 582 Pages, 1999/02

JNC-TJ1400-99-012.pdf:55.26MB

None

Applicability of rapid ion exchange separations with mineral acid-alcohol mixed media to analysis of trace actinides in environmental samples

Usuda, Shigekazu

Proceedings of International Workshop on the Status of Measurement Techniques for the Identification of Nuclear Signatures, p.237 - 244, 1997/00

no abstracts in English

ANALYSIS OF LARGE LEAK SODIUM-WATER REACTION IN LARGE FBR

Tanabe, Hiromi; Hamada, Hirotsugu

PNC TN9410 91-028, 14 Pages, 1991/01

PNC-TN9410-91-028.pdf:0.36MB

A COMPUTER CODE,SWACS,WAS DEVELOPED TO ANALYZE A LARGE LEAK SODIUM-WATER REACTION EVENT IN AN LMFBR STEAM GENERATOR. THE JAPANESE PROTOTYPE REACTOR,MONJU,HAS A COVER GAS SPACE IN ITS STEAM GENERATOR BUT DIFFERENT DESIGNS ARE ALSOCONSIDERED FOR A FUTURE LARGER PLANT. THEREFORE,SWACS WAS MODIFIED TO ANALYZE THESODIUM-WATER REACTION EVENT UNDER SUCH VARIOUS DESIGNS. SO FAR THE CALCULATIONALMODULE OF AN INITIAL SPIKE PRESSURE AND ITS PROPAGATION TO IHTS WAS IMPROVED AND THERESULTS WERE COMPARED WITH THE DATA FROM LLTR AT ETEC, U.S.A. AND WATER-EXPLOSIVE SIMULATION TESTS AT PNC,JAPAN. THE COMPARISON REVEALED A FAIRLY GOODAGREEMENT BETWEEN THE TESTS AND THE ANALYSES. FOLLOWING THE VALIDATION STUDY,SWACS WAS USED FOR THE APPLICATION ANALYSIS TO COMPARE THE PRESSURE BEHAVIORBETWEEN THE COVER-GAS TYPE AND THE NO-COVER-GAS TYPE STEAM GENERATOR OF A FUTURELARGER PLANT. THE ANALYSIS CLARIFIED THE APPLICABILITY OF SWACS TO SUCH A DESIGN STUDYFROM A VIEWPOINT OF SUPPRESSING THE SWR PRESSURE.