A Hybrid Boundary Element Approach without Singular Boundary Integrals
A boundary element formulation for 3D-elastostatics and 3D-elastodynamics is presented which avoids singular boundary integrals. The proposed method is based on a generalized variational principle. A weighted superposition of static fundamental solutions is used for the field approximation in the domain, whereas the displacement and stress field on the boundary are interpolated by well-known polynomial shape functions. By separating time-and space-dependence a symmetric equation of motion is derived with time-independent mass and stiffness matrix. The domain integral over inertia terms, leading to the mass matrix, is analytically transformed to the boundary. Thus, a boundary only formulation is derived. Comparing numerical results with analytical solutions clearly shows that the obtained system of equations is well-suited for dynamic problems.
KeywordsBoundary Element Fundamental Solution Boundary Element Method Load Point Generalize Variational Principle
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