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Showing 1 to 17 of 17 for “"boundary integral equations"”.
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Numerical methods for boundary integral equations in wave body interactions
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1988.
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Three-dimensional layerwise modeling of layered media with boundary integral equations
… multi-layered system through its thickness, and integral Fourier transforms are used to obtain the exact solution for the in-plane problem. Explicit expressions are obtained for the fundamental solution of the typical infinite layer, which are applied in the two-dimensional boundary integral …
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Development and applications of hypersingular boundary integral equations for three-dimensional acoustics and elastodynamics
The boundary integral equation/boundary element method (BIE/BEM) has emerged as a powerful alternative tool to other numerical methods for many problems in engineering. The hypersingular BIE's, which are derivatives of conventional BIE's, are indispensable for the analyses of many problems in …
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Analytical approximations of surface fields induced on convex scatters by exteriorly incident scalar fields
The boundary value problems for the Helmholtz equation give rise to boundary integral equations for the unknown surface field or its normal derivative. These integral equations involve the Helmholtz surface potentials in the form of weakly singular surface integrals. This thesis is based on a …
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Time domain mathematical model for six-degree-of-freedom motion in a wave
… of three-dimensional potential flow leads boundary integral equations over mean wetted body surface with three-dimensional translating pulsating Green function. For numerical implementation Constant Panel Method and Higher-Order Panel Method are introduced as distribution technique of …
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The diffraction of monsters from complex apertures
… concerned with describing scattering through boundary integral equations. Analysis begins with revisiting Lamb’s ingenious solution to the classic knife-edge problem, known for over a century. Maxwell’s equations are solved for an incoming plane wave (subjectto appropriate boundary conditions …
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Galerkin boundary element methods with multiwavelets
In general the numerical solution of boundary integral equations arising from the reformulationof partial differential equations leads to full coefficient matrices. The discretesystem can be solved in O(N2 ) operations by iterative solvers of the ConjugateGradient type possibly with a …
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Higher-Order Finite Element -Boundary Integral Methods for Electromagnetic Scattering and Radiation Analysis
Higher-order finite element-boundary integral (FE-BI) methods are studied for fast and accurate numerical analysis of electromagnetic scattering and radiation problems. First, a higher-order FE-BI method is presented for the scattering analysis of large, deep, and arbitrarily shaped open cavities. …
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Investigating the Feasibility and Stability for Modeling Acoustic Wave Scattering Using a Time-Domain Boundary Integral Equation with Impedance Boundary Condition
… using Fourier transforms, an impedance boundary condition can be used to simulate the acoustic wave scattering by geometric bodies treated with acoustic liners</p> <p>This work considers using either an impedance or an admittance (inverse of impedance) boundary condition to allow for …
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A Class of Robust and Efficient Iterative Methods for Wave Scattering Problems
… iterative techniques for the solution of boundary integral equation formulations of time harmonic scattering problems. The primary result of this effort has been the development of several advanced numerical techniques which enable the dense matrix-vector products associated with the …
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Magnetic fields near microstructured surfaces : application to atom chips
… been investigated numerically with the help of boundary integral equations. The magnetic noise significantly depends on polarizations above flat wires with finite lateral width, in stark contrast to an infinitely wide wire. Correlations between multiple wires are also taken into account. In the …
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A Boundary Element Method for Thermo-poroelasticity with Applications in Rock Mechanics
… treatment and need to be solved numerically. The boundary element method (BEM) has proven suitable for the poroelastic and thermoelastic problems. In this thesis, a two-dimensional transient indirect BEM is developed to solve coupled thermoporoelastic problems.</p><p>The indirect BEM has two …
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Methods of fast Fourier transform in diffraction problems of elastic and acoustic waves with applications to crack mechanics
… to problems in wave dynamics, acoustics, and boundary-value problems of mechanics with mixed boundary conditions. This includes: 1) Development of fast methods for integral equations with convolution kernels arising in these fields of application. Such integral equations, after discretization, …
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Boundary integral equation based numerical solutions of helmholtz transmission problems for composite scatters
… dissertation, an in-depth comparison between boundary integral equation solvers and Domain Decomposition Methods (DDM) for frequency domain Helmholtz transmission problems in composite two-dimensional media is presented. Composite media are characterized by piece-wise constant material …
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Analysis of hybrid electrothermomechanical microactuators with integrated electrothermal and electrostatic actuation
… reduce computational time, we also incorporate a boundary integral formulation to describe the electric potential in the medium surrounding the actuator. We show through the example of a hybrid double-beam actuator, that electrothermomechanical actuation results in low voltage, low power operation …
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Fatigue growth of surface flaws in finite plates
… analyzed a semi-circular surface crack using boundary integral equations. F. W. Smith [15] performed the elastic analysis of the part circular surface flaw problem by the alternating method. J. C. Newman [16] in 1973 derived an equation which related the linear elastic stress intensity factor, …
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A Numerical Scheme for Mullins-Sekerka Flow in Three Space Dimensions
… as one on the two-dimensional interface by using boundary integrals.</p> <p>A semi-implicit scheme to solve the free boundary problem numerically is implemented. Numerical analysis tasks include discretizing surfaces, overcoming node bunching, and dealing with topology change in a toroidal …