Nuclear Power Plant Aging Research CenterThermal Hydraulics and Mechanics Group
Preventing Problems Before They Occur
Accidents and incidents in nuclear power plants can be averted by detecting potential causes of malfunctions. The Thermal Hydraulics and Mechanics Group conducts research related to the evaluation of stress loading and thermal loading, which are consequences of aging, and the proactive prevention of problems.
Thermal Hydraulic Evaluation
Through both numerical analysis and experiments, the evaluation is performed on flow behavior that is a factor in fatigue caused by fluid temperature changes, and in piping deterioration caused by that flow, etc., and prevention measures are examined.
Structural Evaluation
Through combination of numerical analysis with physical experiments, we have been performing technological development to elucidate the effects of a seismic load, the vibrational load during operation, and the thermal load from welds and liquid flow so as to analyze and assess the structural strength of equipment.
Numerical simulation of fluid temperature fluctuation at pipe junctions
Thermal fatigue test rig
Measurement of through-pipe flow velocity distribution using a laser and high-speed camera
Development of a vibrational stress measurement method that helps assess abnormal vibration in small-bore pipes
Numerical simulation for predicting residual stress in welded structures
Key Achievements
• Participation in committee for evaluation of high-cycle thermal fatigue at the Japan Society of Mechanical Engineers
• Took part in development of an industrial standard of the Japan Society of Mechanical Engineers, on the basis of our findings from researches into flow-accelerated corrosion and cavitation
• Took part in development of an industrial standard of the Japan Society of Mechanical Engineers, on the basis of our findings from researches into flow-accelerated corrosion and cavitation
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Seismic stress evaluation system
for tanks in nuclear
power plant
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Technical instruction on design
assessment of clear power
plant facilities