Papers by Keyword: Fluid Structure Interaction (FSI)

Abstract: The Korea Atomic Energy Research Institutes has been developing the SMART (System integrated Modular Advanced ReacTor), an environment-friendly nuclear reactor, for the generation of electricity, and to perform desalination. SMART reactors can be exposed to various external and internal loads caused by seismic and coolant flows. Reactor structures need to be maintained for the reactor’s safety and integrity against these loads during the operational time of the SMART. This paper presents two FE-models, 3-D solid models of the reactor internals in the air and in the coolant, and then compares the results of the dynamic characteristic for the two FE-models using a commercial Finite Element tool, ANSYS V12. A solver was selected by the Block Lanczos method. These FE-models are looking forward to being executed in various researches concerning the SMART in further studies.

Abstract: To simulate skull-CSF-brain interaction relations, a simple finite element head model is established, based on ALE (Arbitrary Lagrangian-Eulerian) and overlapping mesh methods. The responses of head under impact was simulated with this model. The numerical results are coincidence well with the experimental results conducted by Nahum et al. What’s more, it is found that the skull-brain relative displacement and brain injury may be predicted better with the ALE method.

Abstract: The blades are important components of the inverted umbrella aerators. In this paper, the inverted umbrella aerator blade with curved surface, which was arranged according to the variable helix angle of logarithmic spiral line, was designed and simulated. Through the simulation and calculation of the flow field of oxidation ditch that pushed by the blade, based on the fluid-structure interaction analysis, the reliability of the impeller blades has been studied. All the results showing that the new type inverted umbrella surface aerator blade is reliable.

Abstract: The great use of circular cylindrical shells for conveying fluid in modern industrial applications has made of them an important research area in applied mechanics. Many researchers have studied this problem, however just a reduced number of these works have as object the analysis of orthotropic shells. Although most investigations deal with the analysis of elastic isotropic shells in contact with internal and external quiescent or flowing fluid, several modern and natural materials display orthotropic properties and also stiffened cylindrical shells can be treated as equivalent uniform orthotropic shells. In this work, the influence of internal flowing fluid on the dynamic instability and non-linear vibrations of a simply supported orthotropic circular cylindrical shell subjected to axial and lateral time-dependent loads is studied. To model the shell, the Donnell’s non-linear shallow shell theory without considering the effect of shear deformations is used. A model with eight degrees of freedom is used to describe the lateral displacements of the shell. The fluid is assumed to be incompressible and non-viscous and the flow to be isentropic and irrotational. The Galerkin method is applied to derive the set of coupled non-linear ordinary differential equations of motion which are, in turn, solved by the Runge-Kutta method. The obtained results show that the presence of the internal fluid and material properties have a great influence on the vibration characteristics of the shell.

Abstract: Ship coating should be at the right temperature and good ventilated environment. Setting reasonable hang radiant panel for the ship spraying workshop, in the form of radiation heating combined with mechanical air supply to achieve suitable temperature and wind speed. Using the CFD method, by the STAR-CCM+ software, we can simulate the radiation heating workshop space and solid piece. It is concluded that the surrounding air velocity distribution, and observe the change of the temperature field, getting the suitable temperature and air velocity distribution for ship hull surface spraying. Then it can improve the quality of coating.

Abstract: In this paper, systemic FSI numerical simulations for wind-induced dynamic response of saddle-shaped tension membrane structures are performed using ADINA software, and the effects of some parameters such as inlet velocity, wind direction, span, rise-span ratio, tension stiffness and pre-stress of tension membrane are considered. The flow is modeled with the incompressible viscous Navier-Stokes equations and the standard κ-ω turbulence model, and the membrane is assumed as isotropic-linear-elastic material with large displacement and small strain. The rules of FSI numerical simulation for wind-induced dynamic responses of saddle-shaped tension membrane structures are summarized and the wind-induced dynamic coefficients and the wind pressure distribution coefficients are obtained which can be used in the design of membrane structures.

Abstract: Coupled vibration of water and stop log gate in the layered water intake structure will occur under the condition of the sudden load changes. A fluid-structure interaction (FSI) finite element model of the layered water intake structure of a hydropower station was established by using the finite element software ADINA to simulate the process of power on and off and the FSI phenomena of stop log gate during each process, and also verify the security of the scheme. The results show that fluid-structure interaction has a significant impact on the running of the layered water intake.

Abstract: Fluid-Structure Interaction engages with complex geometry especially in biomechanical problem. In order to solve critical case studies such as cardiovascular diseases, we need the structure to be flexible and interact with the surrounding fluids. Thus, to simulate such systems, we have to consider both fluid and structure two-way interactions. An extra attention is needed to develop FSI algorithm in biomechanic problem, namely the algorithm to solve the governing equations, the coupling between the fluid and structural parameter and finally the algorithm for solving the grid connectivity. In this article, we will review essential works that have been done in FSI for biomechanic. Works on Navier–Stokes equations as the basis of the fluid solver and the equation of motion together with the finite element methods for the structure solver are thoroughly discussed. Important issues on the interface between structure and fluid solvers, discretised via Arbitrary Lagrangian–Eulerian grid are also pointed out. The aim is to provide a crystal clear understanding on how to develop an efficient algorithm to solve biomechanical Fluid-Structure Interaction problems in a matrix based programming platform.

Abstract: The model of wind turbine was created by CATIA software, and then the simulation for blades and wind field was conducted by ANSYS software. The phenomena, such as tip vortex of blade, center vortex, and spiral trailing edge vortex caused by the rotating wind turbine, were presented explicitly and the pressure distribution of wind field was obtained. This paper provides some guiding significance to the arrangement of wind turbine and the studies about loading, deformation, and stress of blades.

Abstract: The immersed boundary method (IBM) for the simulation of the interaction between fluid and flexible boundaries in combination with the lattice Boltzmann method (LBM) is described. The LBM is used to compute the flow field, the interaction between fluid and flexible boundaries to be treated by the IBM. To analyze the key factors of combination method and implementation process. An example is presented to verify the efficiency and accuracy of the described algorithm. These will provide a base for large scale simulation involving flexible boundaries in the future.