In the ultrasonic testing for periodic inspection of nuclear power plants, it is necessary to decide the inspection condition and probe scanning range before the inspection. Especially, ultrasonic propagation analysis was difficult for complex curved component such as nozzle parts. Therefore, we have developed an ultrasonic propagation simulation technique for three-dimensional complex curved objects based on the definition of curved surface functions and virtual scanner. We can examine appropriate ins...
英字タイトル:
Development of Ultrasonic Propagation Simulation Technique for Three-Dimensional Complex Curved Surface Shape

When a heat transfer tube wall in a steam generator of a sodium-cooled fast reactor fails, high-pressure steam leaks into low-pressure liquid sodium side. Then the high-temperature and highly corrosive reaction jet causes secondary failures of neighboring heat transfer tubes. The objective of the present study is to develop an experimental method to obtain data that is necessary to validate and improve a safety evaluation code on the sodium?water reaction. In the present paper, the methods of sodium?...
英字タイトル:
Development of Erosion Test Methods on Underexpanded Inert-Gas Impinging Jets Injected in Liquid Sodium

Abstract: Temperature fluctuations. arising when fluids with different temperature are mixed. cause high cycle thermal fatigue to materials of plant components. Thus analyzing the characterist ics of these temperature fluctuations is important for plant maintenance. In this study, a large eddy simulation, one of the detailed turbulence simulation methods. was applied to the analysi s of two typical flow patterns with temperature fluctuations in a tee pipe. Results were compared with the experimental data. ...
英字タイトル:
Evaluation of Fluid Temperature Fluctuations in a Tee Pipe by Detailed Turbulence Simulations

Wastage phenomena occur when a heat transfer tube is failed in a Steam Generator (SG) of Fast Breeder Reactor (FBR) and its mechanism is still unexplained. We focused on Liquid Droplet Impingement Erosion (LDIE) as a factor of the wastage phenomena and performed a basic study with a partial mock-up water test simulating a piping group in SG for quantitative evaluation of LDIE. First, we did visualization tests of high pressure and high speed jet into water. The test section consists of a failure heat ...
英字タイトル:
Study on Rapid Wastage due to Liquid Droplet Impingement on Heat Transfer Tube in SG of Fast Breeder Reactor