The tsunami generated by Great East Japan Earthquake caused the severe accident to the BWR plant of the Fukushima Dai-ichi Nuclear Power Station. This work considered how safety m easures with the re-operation application of the nuclear power plant contributed to the co re damage risk reduction caused by the tsunami using probabilistic risk assessment (PRA)....
英字タイトル:
Examination of the safety measures in the nuclear power plant by tsunami level 1PRA

The high level maintenance technology has become necessary to increase a capacity factor of nuclear power plants. In a nuclear power plant, There are various kinds of troubles concer ning with pipes. One of them is a small leak from a small hole by liquid drop impingement erosion (LDIE). Even such a small leak, it was sometimes a cause of the plant trip and an eco nomical losses about 200M$ during several month outage, by operating a 1000MWe fossil power plant. We conducted a LDIE test by using a test spec...
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Pipe Wall wastage by Liquid Droplet Erosion and It's Countermeasure

The licensing processes on uprating of current light water reactors (LWRs) are classified into three categories by US NRC, one of which is the uprating by MU, Measurement Uncertainty Recapture, targeting the uprating up to 2%. MU is enabled by the measurement-accuracy improvement of a feedwater flowmeter with 0.5~1.7% without issues arising from safety matters and remodeling equipment. Time-of-flight type ultrasonic flowmeters have been widely used in industries. However, it has to be considered the tracea...
英字タイトル:
Current Status on High-accuracy Ultrasonic Flowmeter Development for FeedwaterFlow Rate Measurements in Light Water Reactors