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2008 NTOU. Particular solutions for some engineering problems. Chia-Cheng Tasi 蔡加正 Department of Information Technology Toko University, Chia-Yi County, Taiwan. Overview. Motivation Method of Particular Solutions (MPS) Particular solutions of polyharmonic spline Numerical example I
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2008 NTOU Particular solutions for some engineering problems Chia-Cheng Tasi 蔡加正 Department of Information Technology Toko University, Chia-Yi County, Taiwan
Overview Motivation Method of Particular Solutions (MPS) Particular solutions of polyharmonic spline Numerical example I Particular solutions of Chebyshev polynomials Numerical example II Conclusions
Motivation BEM has evolved as a popular numerical technique for solving linear, constant coefficient partial differential equations. Other boundary type numerical methods: Treffz method, MFS… Advantage: Reduction of dimensionalities (3D->2D, 2D->1D) Disadvantage: domain integration for nonhomogeneous problem For inhomogeneous equations, the method of particular solution (MPS) is needed. In BEM, it is called the dual reciprocity boundary element method (DRBEM) (Partridge, et al., 1992).
Motivation RBF Golberg (1995) Chebyshev MPS with Chebyshev Polynomials spectral convergence MFS Golberg, M.A.; Muleshkov, A.S.; Chen, C.S.; Cheng, A.H.-D. (2003)
Motivation We note that the polyharmonic and the poly-Helmholtz equations are encountered in certain engineering problems, such as high order plate theory, and systems involving the coupling of a set of second order elliptic equations, such as a multilayered aquifer system, or a multiple porosity system. These coupled systems can be reduced to a single partial differential equation by using the Hörmander operator decomposition technique. The resultant partial differential equations usually involve the polyharmonic or the products of Helmholtz operators. Hence My study is to fill an important gap in the application of boundary methods to these engineering problems.
Method of particular solutions Method of particular solutions Method of fundamental solutions, Trefftz method, boundary element method, et al.
Method of particular solutions (Hörmander Operator Decomposition technique) Particular solutions for the engineering problems
Other examples Stokes flow Thermal Stokes flow
Other examples Thick plate Solid deformation
Remark Particular solutions for product operator Particular solutions for engineering problems Hörmander operator decomposition technique
Method of particular solutions (Partial fraction decomposition) Particular solutions for Particular solutions for product operator Partial fraction decomposition
Remark Partial fraction decomposition
Particular solutions of polyharmonic spline (Generating Theorem)
Particular solutions of polyharmonic spline (Generating Theorem)
Particular solutions of polyharmonic spline (Generating Theorem)
Particular solutions of polyharmonic spline (2D Poly-Helmholtz Operator)
Particular solutions of polyharmonic spline (2D Poly-Helmholtz Operator) proof Generating Theorem
Particular solutions of polyharmonic spline (2D Poly-Helmholtz Operator)
Particular solutions of polyharmonic spline (2D Poly-Helmholtz Operator)
Particular solutions of polyharmonic spline (3D Poly-Helmholtz Operator)
Particular solutions of polyharmonic spline (2D Poly-Helmholtz Operator) proof Generating Theorem
Particular solutions of polyharmonic spline (Limit Behavior)
Particular solutions of polyharmonic spline (Limit Behavior)
Particular solutions of Chebyshev polynomials (why orthogonal polynomials) Fourier series: exponential convergence but Gibb’s phenomena Lagrange Polynomials: Runge phenomena Jacobi Polynomials (orthogonal polynomials): exponential convergence
Particular solutions of Chebyshev polynomials (why Chebyshev)
Particular solutions of Chebyshev polynomials (poly-Helmholtz) Generating Theorem Golberg, M.A.; Muleshkov, A.S.; Chen, C.S.; Cheng, A.H.-D. (2003)
Particular solutions of Chebyshev polynomials (polyharmonic)