Development of Coupled Lattice Boltzmann and Finite Element Method for Fluid-Structure Interaction Problems in Commercial Nuclear Power Plants

A commercial nuclear power plant is a complex engineering system which demands extremely high safety and reliability. As the nuclear power plant becomes more compact with a higher density of energy production, the design of a new nuclear power plant becomes more challenge for engineers. A commercial nuclear power plant contains various complex fluid-structure interaction problems that are critical to the safety of the system. These include active and passive interaction between pressure vessels/pipes and the contained and/or surrounding various kinds of fluids including multiphase flows. Such fluid-structure interaction can cause an unexpected failure of the system resulting from instability, resonance, unnecessary contact, fretting, fatigue, etc. As a result, it is critical to assess all possible fluid-structure interaction problems detrimental to the nuclear power plants. However, physical testing of all these problems is almost impossible to conduct. Therefore, it is necessary to have a reliable and efficient analysis tool to assess those fluid-structure interaction problems occurring at the nuclear power plants. In this regard, Korea Institute of Nuclear Safety has embarked on a research project to develop her own original software (computer program) in application to complex fluid-structure interaction phenomena, which is critical for regulatory safety evaluation of commercial nuclear power plants. This paper presents the approach and methodology for the development of the fluid-structure interaction analysis computer program as well as the result of preliminary study conducted to develop a promising coupled technique which will be used for designing the computer program