Solution Of Fluid-Structure Interaction Basing On ALE Method

In this dissertation, two basic problems about FSI (Fluid Structure Interaction) are analyzed first. The one is ALE (Arbitrary Lagrange-Euler) description and the fluid dynamic equations under this description, the other is SUPG (Streamline Upwind Petrov Galerkin) finite elements method for fluid dynamic equations. Then ALE and SUPG methods are combined to form ALE/SUPG finite elements equations for fluid dynamics, which is the key to the solution of FSI system. Lagrange description and Galerkin method are chose for structure field. For FSI problems, one special staggered solution method named synchronized and staggered solution method is contrived in this dissertation. It is chose to avoid the drawbacks of the whole solution method and the classic staggered solution method, which is called time step staggered solution method in this dissertation to distinguish from the synchronized and staggered solution method. Basing on the predictor-multicorrector time integral method, the processes and flow chart of resolution of FSI system using synchronized and staggered solution method are displayed in chapter 4. To testify the validity of the algorithms and computer programs used in this dissertation, two examples of FSI system are computed at the end.The contents of this dissertation are arranged as follow:In chapter 1, the engineering background of FSI system and its involving ALE description methods, upwind finite elements methods and the resolution methods are introduced.In chapter 2, the basic theories of ALE description are briefly recounted, then the fluid dynamic equations under ALE description are deduced.In chapter 3, SUPG finite element equations for fluid dynamic problem are formed under the Euler description, and used to solve the fluid field with fixed boundary.In chapter 4, on the ground of chapter 2 and chapter 3, synchronized and staggered solution method basing on ALE and SUPG is contrived for FSI system. Its processes and flow chart are displayed.In chapter 5, the method given in chapter 4 is used to solve fluid rigid interaction problem and fluid elastic plate interaction problem.Chapter 6 sums up the whole dissertation.