"This thesis is to discuss the bilinear and 2D linear immersed finite element (IFE) solutions generated from the algebraic multigrid solver for both stationary and moving interface problems. In contrast to the body-fitting mesh restriction of the traditional finite element methods or finite difference methods for interface problems, a number of numerical methods based on structured meshes independent of the interface have been developed. When these methods are applied to the real world applications, we often need to solve the corresponding large scale linear systems many times, which demands efficient solvers. The algebraic multigrid (AMG) method is a natural choice since it is independent of the geometry, which may be very complicated in interface problems. However, for those methods based on finite difference formulation and a structured mesh independent of the interface, the stiffness matrix of the linear system is usually not symmetric positive-definite, which demands extra efforts to design efficient multigrid methods. On the other hand, the stiffness matrix arising from the IFE methods are naturally symmetric positive-definite. Hence the IFE-AMG algorithm is proposed to solve the linear systems of the bilinear and 2D linear IFE methods for both stationary and moving interface problems after the IFE and multi-grid methods are reviewed respectively. The numerical examples demonstrate the features of the proposed algorithm, including the optimal convergence in both Ł² and semi-H¹ norms of the IFE-AMG solutions, the high efficiency with proper choice of the components and parameters of AMG, the influence of the tolerance and the smoother type of AMG on the convergence of the IFE solutions for the interface problems, and the relationship between the cost and the moving interface location"--Abstract, page iii.
Mathematics and Statistics
M.S. in Applied Mathematics
Missouri University of Science and Technology
ix, 70 pages
© 2013 Wenqiang Feng, All rights reserved.
Thesis - Open Access
Library of Congress Subject Headings
Finite element method -- Computer programs
Interfaces (Physical sciences) -- Mathematics -- Computer simulation
Algebraic number theory -- Computer simulation
Differential equations -- Computer simulation
Numerical analysis -- Computer simulation
Electronic OCLC #
Feng, Wenqiang, "Immersed finite element method for interface problems with algebraic multigrid solver" (2013). Masters Theses. 5371.