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Showing 1 to 20 of 39 for “"Spectral Element Method"”.
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A Spectral Element Method for Viscoelastic Fluid Flow
This thesis establishes a new spectral element technique for solving incompressible Newtonian flows and viscoelastic flows of non-Newtonian fluids. In the numerical simulation of the incompressible Newtonian fluid in two dimensions, the spectral element approximations of the Stokes and …
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A discontinuous Galerkin spectral element method compressible flow solver
… flow simulation using the discontinuous Galerkin spectral element method. The algorithms are designed for simulation of compressible turbulence in realistic engineering geometries that are relevant to a broad range of mechanical engineering applications. Such problems are difficult because of high …
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Stability Analysis of Time Delay Systems Using Spectral Element Method
… work is to develop a practical and comprehensive methodology to study the response and the stability of various delay differential equations (DDEs). The development of these new analysis techniques is motivated by the existence of delays in the governing equations of many physical systems such as …
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A Legendre spectral element method for the rotational Navier-Stokes equations
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mathematics, 1995.
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The fourier spectral element method for vibration analysis of general dynamic structures
<p>The Fourier Spectral Element Method (FSEM) was proposed by Wen Li on the vibration of simple beams (Li, 1999), and was extended to the vibration of rectangular plates (Li, 2004). This dissertation proposes a revised formulation on the vibration of rectangular plates with general boundary …
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Development of a high-order accurate reservoir simulator using spectral element method
… often based on finite volume or finite element methods, can be computationally prohibitive to fully resolve the physics of flows with sharp fronts. A high-order numerical scheme with strong stability properties and robustness to accurately resolve the physics of reservoir flows is thus …
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High-Resolution Digital Noise Mapping of Urban Environments Using the Spectral Element Method
… in urban areas. This research employs the spectral element method (SEM), a numerical technique known for its ability to model complex geometries accurately. The SEM is employed to create high-resolution digital soundscape maps that allow for a comprehensive analysis of the spatial and …
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Least squares spectral element method for laminar and turbulent flows, –continuous and discontinuous approaches–
In this research, application of a least squares spectral element method for compressible laminar and turbulent flow problems is investigated. For the turbulent Reynolds Averaged Navier-Stokes (RANS), a modified Spalart-Allmaras (SA) turbulence model is employed and integrated with the mean flow …
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Spectral Integral Method and Spectral Element Method Domain Decomposition Method for Electromagnetic Field Analysis
<p>In this work, we proposed a spectral integral method (SIM)-spectral element method (SEM)- finite element method (FEM) domain decomposition method (DDM) for solving inhomogeneous multi-scale problems. The proposed SIM-SEM-FEM domain decomposition algorithm can efficiently handle problems with …
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A Legendre spectral element method for simulation of incompressible unsteady viscous free-surface flows
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1989.
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Highly scalable solution of incompressible Navier-Stokes equations using the spectral element method with overlapping grids
… is based on a variant of the Schwarz alternating method in which the solution is advanced in parallel in separate overlapping subdomains. In each domain, the governing equations are discretized with an efficient high-order spectral element method (SEM). At each step, subdomain boundary data are …
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Application of the Fekete spectral element method in stress analysis of plates involving holes and complex geometries
In an effort to prove the effectiveness of a methodology that computes more efficiently than traditional FEM methods, this paper details a method that allows for the accurate and efficient solution of an elasticity problem using an hp-SEM code. The code can interchange basis functions to allow us …
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Implementation of a high order Discontinuous Galerkin Spectral Element Method for the Euler and Navier-Stokes equations on unstructured grids
Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-05-01
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Convective mass transport for viscous flow past an evolving boundary
"A Boundary Integral-Spectral Element method is developed that solves two-dimensional Helmholtz equations. This high order technique is shown to be adaptable to a variety of boundary conditions and solves elliptic partial differential equations efficiently such that it is applicable to moving …
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Wavefront Healing and Tomographic Resolution of Mantle Plumes
… speed imaged in the lowermost mantle, we use a Spectral Element Method (SEM) to simulate global seismic wave propagation in 3-D wavespeed models and measure frequency-dependent P-, S-, Pdiff- and Sdiff-wave traveltime anomalies caused by plume structures in the lowermost mantle. We compare SEM …
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Surface wave propagation in 3-D anelastic media
… simulations in 3-D earth models using a Spectral Element Method. Comparison between phase delays caused by 3-D wave speed structures and those caused by 3-D Q variations show that anelastic dispersion due to lateral perturbation in Q is important in long-period surface wave and can …
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Imaging Resolution of the 410-km and 660-km Discontinuities
… based on wave propagation simulations using a Spectral Element Method (SEM). We investigate finite-frequency effects of direct P waves as well as P-to-S converted waves by varying the length scale of discontinuity topography in the transition zone. We show that wavefront healing effects are …
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Efficient Spectral-Element Methods For Acoustic Scattering And Related Problems
… on the development of high-order numerical methods for acoustic and electromagnetic scattering problems, and nonlinear fluid-structure interaction problems.</p> <p>For the scattering problems, two cases are considered: 1) the scattering from a doubly layered periodic structure; and 2) the …
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Natural convection of molten salt in laterally heated and top cooled vertical cylinders
… 1.0, 1.5, 2.0) for a total of nine cases. The spectral element method with high polynomial resolution is used to perform the simulations, using the open-source code Nek5000. The different flow patterns and temperature distributions observed for the nine cases are documented. Validation of the …
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Effects of fault failure parameterization and bulk rheology on earthquake rupture
… dynamic system. We then perform 2D finite element models of earthquake rupture nucleation and propagation to gain insight into how different failure laws affect the different phases of the earthquake cycle in the case of an added fault dimension. The rheological part of this work explores …
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