PIPE RUPTURE ANALYSIS CONSIDERING FLUID-STRUCTURE INTERACTION

Global warming is caused by the emission of greenhouse gases, like CO2. Nuclear energy is one of the main sources of low-carbon energy. In the events of serious accidents, a nuclear power plant may emit radioactivity that is harmful to human health. Nuclear power should be used after enough evidence of its safety is provided. Measures for safety of nuclear power plants, such as autogenous control and LBB, have been developed. Moreover, there is requirement with respect to the design, safety, equipments components and systems of nuclear plant. For example, it is necessary to place components that restrain pipe whip behavior, and to design peripheral equipments that may be affected by high-pressured fluid in pipe rupture accidents [1], [2]. In the case of pipe rupture that occurs to structures such as nuclear plants and steam generators, a pipe deforms releasing its inner high-pressured fluid. In previous studies, the pipe whip behavior analyses have been performed by using blowdown thrust force that is estimated by fluid analysis. In this study, we simulate pipe whip behavior and reduction of blowdown thrust force by releasing inner fluid to the atmosphere. The analysis model is an elbow pipe and high-pressure fluid running inside. We considered fluid-structure interaction effect in the analysis because ovalization of the cross-section of the elbow part as well as a change of the elbow torus radius affects fluid flow blowing out from the ruptured part of the pipe.