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[en] This study presents to conform the shielding integrity of the KSC-4 shipping cask for loading 4 PWR fuel assemblies. The source terms of the KSC-4 shipping cask was calculated by using the ORIGEN-2 computer code. The shielding analysis was carried by the ANISN computer code. The compared results between the calculated and the measured dose rate shows that the shielding integrity of the KSC-4 cask was verified within the allowable values specified as the transport regulations
[en] Quenching experiments of a hot solid sphere in dilute water solutions of poly( ethylene oxide) polymer have been conducted for the purpose of investigating the physical mechanisms of the suppression of vapor explosions in this polymer solution. A test sphere heated to 700 .deg. C in a furnace was immersed into polymer solutions of various concentrations at 30 .deg. C. The key observation in this study was that the minimum film boiling temperature(Δ TMIN) rapidly decreased from over 700 .deg. C for pure water to about 150 .deg. C as the polymer concentration was increased up to 300ppm. It was also observed that the vapor film behaved more stable against an external disturbance at higher polymer concentration
[en] This investigation concerns thermal striping by liquid sodium, and focuses on improvement of improving the strength evaluation method of the high temperature structure and to develop a more appropriate structural design method. A sodium thermal shock test was conducted at a sufficiently high frequency with a simple high-temperature-structure model. We examined the temperature distribution in the vicinity of the metal surface, the initiation of cracks and their propagation, and the length of the arrested cracks based on the stress intensity factor of the surface cracks caused by local stress arising near the surface. We also propose a strength evaluation method for thermal striping. (author)
[en] The effects of dynamic viscosity and surface tension of melts were experimentally examined to clarify the sensitivity of melts to the disturbances triggering off vapor explosion. Experiments were conducted by dropping molten tin or/and zinc into water in two dropping forms. It was observed that molten tin, which has a relatively small dynamic viscosity and surface tension, always resulted in metal-water interaction in both dropping forms, and zinc melt, which has a relatively large dynamic viscosity and surface tension, didn't cause metal-water interaction in both dropping forms. The molten tins dropped in a slender cylindrical shape, produces metal-water interaction more moderate than that dropped in a lumped-shape. It was also confirmed that when molten zinc and tin were dropped simultaneously to expose molten zinc to the disturbance produced by tin-water interaction, zinc showed a trace of metal-water interaction. These results indicate that the occurrence of vapor explosion is closely related to the physical property and the dropping form of the melt. (author)
[en] In this study, a condensation heat transfer model, coupled with a three-dimensional two-phase flow analysis, was developed. In the heat transfer model, the liquid film flow rate on the heat transfer tubes was calculated by a mass balance equation and the liquid film thickness was calculated from the liquid film flow rate using Nusselt's laminar flow model and Fujii's equation for the steam velocity effect. The model was verified by condensation heat transfer experiments. In the experiments, 112 horizontal, staggered tubes with an outer diameter of 16mm and length of 0.55m were used. The calculated over-all heat transfer coefficients agreed with the data within ±5% under the inlet quality conditions of 13-100%. Based on a three-dimensional two-phase flow analysis, an improved feed-water heater with support plates, which have flow holes between the upper and lower tube bundles, was designed. The total heat exchange capacity of the improved feed-water heater increased about 6%. (author)
[en] This book includes introduction table of contents chapter 1 finite element idealization introduction summary of the finite element method equilibrium and compatibility in the finite element solution degrees of freedom symmetry and anti symmetry modeling guidelines local analysis example references chapter 2 static analysis structural geometry finite element models analysis procedure modeling guidelines references chapter 3 dynamic analysis models for dynamic analysis dynamic analysis procedures modeling guidelines and modeling guidelines.
[en] This book contains property of pneumatic pressure drive, pneumatic pressure device like air cleaning, pressure control, lubricators, air pressure pipe, kinds and function of pneumatic pressure equipment like pneumatic cylinders, pneumatic motor, flow control valve, direction control valve, design of pneumatic control circuit, pneumatic system design, cause and measurement of pneumatic circuit failure, PLC and pneumatic control like introduction and system application and method of PLC programing.
[en] This book consists of five chapters, which describe plasticizer ; summary, synthesis of plasticizer, basic notion, analysis and test on plasticizer, stabilizer ; stabilizer for plastic, an antioxidant, phosphorous acid estelle, ultraviolet ray absorbent, performance of stabilizer, influence on another additives, mix case of PVC production and analysis method for stabilizer, ultraviolet ray absorbent ; basic property and ultraviolet ray absorbent maker, anti-static agent ; basics, anti-static agent of a high molecule and analysis of anti-static agent, flame retardant of plastic.
[en] This work investigated in situ characterization of room temperature fatigue damage in Al6061 material using an ultrasonic surface wave technique. The goal of the work was to show that an in situ surface wave technique would provide valuable information concerning fatigue damage initiation and accumulated process in Al6061 material of aircraft application. Two kinds of plate specimen were made for this study. The specimens were at least 160 mm in length to accommodate the ultrasonic surface wave transducer with 2 or 4 MHz frequency, while the specimen is held in the grips of MTS hydraulic fatigue test machine. Once the transducer were in place, ultrasonic data was recorded by both digital ultrasonic flaw detecter(USD10) and computer before the fatigue tests were started. The fatigue tests were then started and the specimen were cycled to the desired number of cycles and finally to the fracture of specimen. The ultrasonic data were recorded for two kinds of applied stress level with the some stress ratio(R=0.01). It was found clearly that the velocity and attenuation of ultrasonic surface wave were changed due to the number of fatigue cycle as well as the change of applied stress levels. From the results, the applicability of in situ ultrasonic surface wave technique to evaluate successive change of fatigue damage of Al6061 was discussed in more details.
[en] Ultrasonic velocities are widely used in the investigation of material properties. In this paper, a micromechanics model and the ultrasonic velocity were used to develop a nondestructive method to determine the density variation due to porosity in structural SiC. The micromechanics model developed can consider the pore shape and orientation. The model also takes into account the interaction between pores so that it can be applied to the material with high porosity content. A contact pulse overlap method was used to measure the ultrasonic velocities of porous SiC samples, and there was a linear correlation between the velocity and density (or porosity). Using the model and the measured velocity, the bulk density was calculated and the calculated density was in good agreement with that obtained by Archimedes' method.