subject:(Boundary condition)

Delft University of Technology

1. Diederen, D. (author). The open boundary equation.

Degree: 2015, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:6c923809-0cfd-4ca7-b051-1aaad9387273

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Consider an estuary which is described by two governing equations for two variables, the water level 'zeta' and the velocity 'u'. Having two governing equations… (more)

Subjects/Keywords: estuary; boundary condition; Saint Venant

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APA (6^th Edition):

Diederen, D. (. (2015). The open boundary equation. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:6c923809-0cfd-4ca7-b051-1aaad9387273

Chicago Manual of Style (16^th Edition):

Diederen, D (author). “The open boundary equation.” 2015. Masters Thesis, Delft University of Technology. Accessed January 23, 2021. http://resolver.tudelft.nl/uuid:6c923809-0cfd-4ca7-b051-1aaad9387273.

MLA Handbook (7^th Edition):

Diederen, D (author). “The open boundary equation.” 2015. Web. 23 Jan 2021.

Vancouver:

Diederen D(. The open boundary equation. [Internet] [Masters thesis]. Delft University of Technology; 2015. [cited 2021 Jan 23]. Available from: http://resolver.tudelft.nl/uuid:6c923809-0cfd-4ca7-b051-1aaad9387273.

Council of Science Editors:

Diederen D(. The open boundary equation. [Masters Thesis]. Delft University of Technology; 2015. Available from: http://resolver.tudelft.nl/uuid:6c923809-0cfd-4ca7-b051-1aaad9387273

University of California – Berkeley

2. Sagiyama, Koki. Absorbing Boundary Conditions for Scalar and Elastic Waves in the Time-Domain.

Degree: Civil and Environmental Engineering, 2013, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/4858f1n4

► Absorbing boundary conditions are a requisite element of many computational wave prop-agation problems. With our main motivation being the anchor loss simulations of Micro-electromechanical Systems… (more)

▼ Absorbing boundary conditions are a requisite element of many computational wave prop-agation problems. With our main motivation being the anchor loss simulations of Micro-electromechanical Systems (MEMS) in three dimensions, efficient time-domain absorbingboundary conditions which do work well for elastodynamics are in demand. In this workwe investigate three classes of absorbing boundary conditions which we believe are promis-ing, viz., perfectly matched layers (PMLs), perfectly matched discrete layers (PMDLs), andhigh-order absorbing boundary conditions (HOABCs). We first devise a PML formulation onspherical domains which is particularly suited for the simulation of a large class of MEMS-resonator systems. What distinguishes our original PML formulation from most existingPML formulations is that it works with standard numerical solvers such as discontinuousGalerkin methods on unstructured meshes and that it allows for a natural application ofNeumann boundary conditions on traction-free surfaces. It is also of significant impor-tance in large three-dimensional problems that our formulation has fewer number of degreesof freedom than any existing PML formulations. We demonstrate the applicability of ourspherical PML formulation to large problems via a simulation of a three-dimensional double-disk resonator in the time-domain using a discontinuous Galerkin method and an explicitfourth-order Runge-Kutta method. PMDL methods and HOABC methods are alternativesto PML methods, which in the context of the scalar wave equation surpass PML methods intheir overall behavior. Unfortunately, their mathematical properties are not as well under-stood in the context of elastodynamics and, at least in a certain setting, they are known toresult in unstable systems. Due to its involved nature, we focus in this work on the analysisof PMDLs/HOABCs for the scalar wave equation and prove several useful identities whichwill also be useful in the analysis of PMDLs/HOABCs for elastodynamics.

Subjects/Keywords: Civil engineering; Applied mathematics; absorbing boundary condition; anchor-loss; high-order absorbing boundary condition; MEMS; perfectly matched layer; radiation boundary condition

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APA (6^th Edition):

Sagiyama, K. (2013). Absorbing Boundary Conditions for Scalar and Elastic Waves in the Time-Domain. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/4858f1n4

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sagiyama, Koki. “Absorbing Boundary Conditions for Scalar and Elastic Waves in the Time-Domain.” 2013. Thesis, University of California – Berkeley. Accessed January 23, 2021. http://www.escholarship.org/uc/item/4858f1n4.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sagiyama, Koki. “Absorbing Boundary Conditions for Scalar and Elastic Waves in the Time-Domain.” 2013. Web. 23 Jan 2021.

Vancouver:

Sagiyama K. Absorbing Boundary Conditions for Scalar and Elastic Waves in the Time-Domain. [Internet] [Thesis]. University of California – Berkeley; 2013. [cited 2021 Jan 23]. Available from: http://www.escholarship.org/uc/item/4858f1n4.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sagiyama K. Absorbing Boundary Conditions for Scalar and Elastic Waves in the Time-Domain. [Thesis]. University of California – Berkeley; 2013. Available from: http://www.escholarship.org/uc/item/4858f1n4

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University

3. Zhou, Yuhan. Numerical Methods for Parasitic Extraction of Advanced Integrated Circuits.

Degree: PhD, Computer Engineering, 2017, Texas A&M University

URL: http://hdl.handle.net/1969.1/187305

► FFinFETs, also known as Fin Field Effect Transistors, are a type of non-planar transistors used in the modern integrated circuits. Fast and accurate parasitic capacitance… (more)

▼ FFinFETs, also known as Fin Field Effect Transistors, are a type of non-planar transistors used in the modern integrated circuits. Fast and accurate parasitic capacitance and resistance extraction is crucial in the design and verification of Fin- FET integrated circuits. Though there are wide varieties of techniques available for parasitic extraction, FinFETs still pose tremendous challenges due to the complex geometries and user model of FinFETs. In this thesis, we propose three practical techniques for parasitic extraction of FinFET integrated circuits. The first technique we propose is to solve the dilemma that foundries and IP vendors face to protect the sensitive information which is prerequisite for accurate parasitic extraction. We propose an innovative solution to the challenge, by building a macro model around any region in 2D/3D on a circuit where foundries or IP vendors wish to hide information, yet the macro model allows accurate capacitance extraction inside and outside of the region. The second technique we present is to reduce the truncation error introduced by the traditional Neumann boundary condition. We make a fundamental contribution to the theory of field solvers by proposing a class of absorbing boundary conditions, which when placed on the boundary of the numerical region, will act as if the region extends to infinity. As a result, we can significantly reduce the size of the numerical region, which in turn reduces the run time without sacrificing accuracy. Finally, we improve the accuracy and efficiency of resistance extraction for Fin-FET with non-orthogonal resistivity interface through FVM and IFEM. The performance of FVM is comparable to FEM but with better stability since the conservation law is guaranteed. The IFEM is even better in both efficiency and mesh generation cost than other methods, including FDM, FEM and FVM. The proposed methods are based on rigorous mathematical derivations and verified through experimental results on practical examples Advisors/Committee Members: Shi, Weiping (advisor), Nevels, Robert D. (committee member), Li, Peng (committee member), Sarin, Vivek (committee member).

Subjects/Keywords: Macro Model; Absorbing boundary condition; IFEM

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APA (6^th Edition):

Zhou, Y. (2017). Numerical Methods for Parasitic Extraction of Advanced Integrated Circuits. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/187305

Chicago Manual of Style (16^th Edition):

Zhou, Yuhan. “Numerical Methods for Parasitic Extraction of Advanced Integrated Circuits.” 2017. Doctoral Dissertation, Texas A&M University. Accessed January 23, 2021. http://hdl.handle.net/1969.1/187305.

MLA Handbook (7^th Edition):

Zhou, Yuhan. “Numerical Methods for Parasitic Extraction of Advanced Integrated Circuits.” 2017. Web. 23 Jan 2021.

Vancouver:

Zhou Y. Numerical Methods for Parasitic Extraction of Advanced Integrated Circuits. [Internet] [Doctoral dissertation]. Texas A&M University; 2017. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/1969.1/187305.

Council of Science Editors:

Zhou Y. Numerical Methods for Parasitic Extraction of Advanced Integrated Circuits. [Doctoral Dissertation]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/187305

University of Melbourne

4. Honig, Christopher David Frederick. Validation of the no slip boundary condition at solid-liquid interfaces.

Degree: 2008, University of Melbourne

URL: http://hdl.handle.net/11343/35118

► This thesis describes the study of the hydrodynamic boundary condition at the solid-liquid interface using the colloidal probe Atomic Force Microscope. Quantitative comparison between measured… (more)

Subjects/Keywords: hydrodynamic boundary condition

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APA (6^th Edition):

Honig, C. D. F. (2008). Validation of the no slip boundary condition at solid-liquid interfaces. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/35118

Chicago Manual of Style (16^th Edition):

Honig, Christopher David Frederick. “Validation of the no slip boundary condition at solid-liquid interfaces.” 2008. Doctoral Dissertation, University of Melbourne. Accessed January 23, 2021. http://hdl.handle.net/11343/35118.

MLA Handbook (7^th Edition):

Honig, Christopher David Frederick. “Validation of the no slip boundary condition at solid-liquid interfaces.” 2008. Web. 23 Jan 2021.

Vancouver:

Honig CDF. Validation of the no slip boundary condition at solid-liquid interfaces. [Internet] [Doctoral dissertation]. University of Melbourne; 2008. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/11343/35118.

Council of Science Editors:

Honig CDF. Validation of the no slip boundary condition at solid-liquid interfaces. [Doctoral Dissertation]. University of Melbourne; 2008. Available from: http://hdl.handle.net/11343/35118

5. Kärkkäinen, Mikko. Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269295/

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Modeling of interfaces and layers with the finite-difference time-domain method (FDTD) is considered in this thesis. New numerical models are developed and verified. A surface… (more)

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Modeling of interfaces and layers with the finite-difference time-domain method (FDTD) is considered in this thesis. New numerical models are developed and verified. A surface impedance boundary condition relates the tangential electric and magnetic fields on an interface between two materials. The exact surface impedance uniquely defines the electromagnetic fields outside the material. The material structure is removed from the computational space. The resulting computational savings are huge in electrically large problems, like the modeling of coated targets in military applications. Using the surface impedance techniques in numerical methods is extremely reasonable when the reflection of electromagnetic fields from materials is difficult to compute directly. For example, if the wavelength inside the material under investigation is very small compared to the wavelength outside the material, the straightforward discretization of the fields inside the material is not a clever approach. The surface impedance boundary conditions may be utilized in such situations. In this thesis, a higher-order FDTD-model of interfaces with metals and semiconductors is developed and verified. As the most important new feature, the model takes arbitrary excitations into account in a general fashion using spatial derivatives on the interface. Novel techniques for modeling of dielectric layers on metal surfaces are also developed. Application of the surface impedance concept to derive analytical absorbing boundary conditions is also considered. An alternative and original model for electrically thin dispersive layers is introduced. Unusual electromagnetic properties of dispersive layers are numerically studied in the frequency range, where the real parts of material parameters are negative. Applications of the surface impedance concept to modeling of antennas with artificial electromagnetic materials are presented with numerical results for prototype devices.

Helsinki University of Technology Radio Laboratory publications. S, ISSN 1456-3835; 264

Advisors/Committee Members: Helsinki University of Technology, Department of Electrical and Communications Engineering, Radio Laboratory.

Subjects/Keywords: FDTD; surface impedance boundary condition; dielectric layer; surface impedance; absorbing boundary condition; metamaterial

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APA (6^th Edition):

Kärkkäinen, M. (2004). Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269295/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kärkkäinen, Mikko. “Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method.” 2004. Thesis, Helsinki University of Technology. Accessed January 23, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269295/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kärkkäinen, Mikko. “Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method.” 2004. Web. 23 Jan 2021.

Vancouver:

Kärkkäinen M. Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Jan 23]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269295/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kärkkäinen M. Modeling of Interfaces and Layers with the Finite-Difference Time-Domain Method. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269295/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology

6. Al Sadan, R.I.M. (author). Application of seismic interferometry by Multidimensional Deconvolution to USArray data.

Degree: 2015, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:6d1cc548-6e25-4631-a584-38ca10b8d31d

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Seismic interferometry by crosscorrelation has found wide application over the last decade. With which, the Green’s function is retrieved between two receiver positions. Because the… (more)

Subjects/Keywords: Seismic Interferometry; Multidimensional Deconvolution (MDD); USArray; Reflecting boundary condition; Absorbing boundary condition

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APA (6^th Edition):

Al Sadan, R. I. M. (. (2015). Application of seismic interferometry by Multidimensional Deconvolution to USArray data. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:6d1cc548-6e25-4631-a584-38ca10b8d31d

Chicago Manual of Style (16^th Edition):

Al Sadan, R I M (author). “Application of seismic interferometry by Multidimensional Deconvolution to USArray data.” 2015. Masters Thesis, Delft University of Technology. Accessed January 23, 2021. http://resolver.tudelft.nl/uuid:6d1cc548-6e25-4631-a584-38ca10b8d31d.

MLA Handbook (7^th Edition):

Al Sadan, R I M (author). “Application of seismic interferometry by Multidimensional Deconvolution to USArray data.” 2015. Web. 23 Jan 2021.

Vancouver:

Al Sadan RIM(. Application of seismic interferometry by Multidimensional Deconvolution to USArray data. [Internet] [Masters thesis]. Delft University of Technology; 2015. [cited 2021 Jan 23]. Available from: http://resolver.tudelft.nl/uuid:6d1cc548-6e25-4631-a584-38ca10b8d31d.

Council of Science Editors:

Al Sadan RIM(. Application of seismic interferometry by Multidimensional Deconvolution to USArray data. [Masters Thesis]. Delft University of Technology; 2015. Available from: http://resolver.tudelft.nl/uuid:6d1cc548-6e25-4631-a584-38ca10b8d31d

Penn State University

7. Suo, Qiuling. the implementation of a time domain impedance boundary condition.

Degree: 2015, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/27305

► Trailing edge noise is an important source of airframe noise. It is mainly caused by the turbulent pressure fluctuations passing an edge discontinuity. A promising… (more)

▼ Trailing edge noise is an important source of airframe noise. It is mainly caused by the turbulent pressure fluctuations passing an edge discontinuity. A promising passive modification for noise reduction is to use porous or partly porous airfoils. Some of the numerical studies of the porous airfoils focus on describing the complete phenomenon. The flow inside the porous region is investigated separately from the outside flow field. However, this is often computationally demanding and time consuming. For engineering purposes, a gross description of the effects of the impedance materials on incident acoustic waves is preferred. The method of time-domain impedance boundary condition is attractive to study noise scattering of absorbing surfaces. The acoustic impedance is used to describe the properties of an absorbing material. It is defined in the frequency domain as the ratio of the acoustic pressure to the acoustic velocity normal to the porous or impedance surface. Most classical impedance models were obtained in the frequency domain, and to obtain a time domain impedance boundary condition is not straightforward. In this thesis, a three-parameter model based on the mass-spring-damper system is adopted. It is verified to have a stable solution. The key to the implementation of this model is to use a ghost point outside the computational domain. This ensures that the boundary points satisfy both the discretized Euler equations and the absorbing boundary condition. Numerical results for the normal-incidence impedance tube problems show a good agreement with the analytical results. The time domain impedance boundary condition has also been developed into a two-dimensional form. An initial example problem is a Gaussian pressure pulse propagating in a uniform Cartesian grid. After that, the simulation is modified into the curvilinear coordinates to simulate the acoustic scattering around a circular cylinder. The results qualitatively show that the absorbing boundaries do reduce the amplitude of the reflected pulse. Having demonstrated simulations for a curved surface, the time domain impedance boundary condition is applied to an impedance-treated airfoil. This code could be used to find a better design of the geometry of the porous trailing edge, and to provide a better choice of the properties of the impedance. Advisors/Committee Members: Philip John Morris, Thesis Advisor/Co-Advisor.

Subjects/Keywords: time domain impedance boundary condition; absorbing boundary; porous airfoil

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APA (6^th Edition):

Suo, Q. (2015). the implementation of a time domain impedance boundary condition. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/27305

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Suo, Qiuling. “the implementation of a time domain impedance boundary condition.” 2015. Thesis, Penn State University. Accessed January 23, 2021. https://submit-etda.libraries.psu.edu/catalog/27305.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Suo, Qiuling. “the implementation of a time domain impedance boundary condition.” 2015. Web. 23 Jan 2021.

Vancouver:

Suo Q. the implementation of a time domain impedance boundary condition. [Internet] [Thesis]. Penn State University; 2015. [cited 2021 Jan 23]. Available from: https://submit-etda.libraries.psu.edu/catalog/27305.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Suo Q. the implementation of a time domain impedance boundary condition. [Thesis]. Penn State University; 2015. Available from: https://submit-etda.libraries.psu.edu/catalog/27305

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université de Bordeaux I

8. Poux, Alexandre. Conditions limites de sortie pour les méthodes de time-splitting appliquées aux équations Navier-Stokes : Outflow boundary conditions for time-splitting methods applied to Navier-Stokes equations.

Degree: Docteur es, Mécanique, 2012, Université de Bordeaux I

URL: http://www.theses.fr/2012BOR14656

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La simulation d’écoulements incompressibles pose de nombreuses difficultés. Une première est la question de savoir comment traiter la contrainte d’incompressibilité et le couplage vitesse/pression afin… (more)

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La simulation d’écoulements incompressibles pose de nombreuses difficultés. Une première est la question de savoir comment traiter la contrainte d’incompressibilité et le couplage vitesse/pression afin d’obtenir une solution précise à moindre coût. Pour cela, nous nous intéressons en particulier à deux méthodes de time splitting : la correction de pression et la correction de vitesse. Une seconde difficulté porte sur des conditions limites de sortie. Nous nous intéressons ici à deux d’entre elles : la condition limite de traction et la condition limite d’Orlanski. Après avoir détaillé les difficultés pouvant apparaître lors de l’implémentation des méthodes de time-splitting, nous proposons une nouvelle implémentation de la condition limite de traction qui permet d’améliorer les ordres de convergence obtenus. Nous nous intéressons ensuite à la condition limite d’Orlanski qui nécessite une certaine vitesse d’advection C dans la direction normale à la limite dont nous proposons ici une nouvelle définition. Nos propositions sont confrontées à de multiples écoulements physiques afin de valider leurs comportements : l’écoulement en aval d’une marche descendante, l’écoulement au niveau d’une bifurcation,l’écoulement autour d’un obstacle et des écoulements de Poiseuille-Rayleigh-Bénard.

One of the understudied difficulties in the simulation of incompressible flows is how to treat the incompressibilityconstraint and the velocity/pressure coupling in order to obtain an accurate solution at low computationnalcost. In this context, we develop two methods: pressure-correction and velocity-correction. An anotherdifficulty is due to the boundary conditions. We study here two of them : the traction boundary condition andthe Orlanski boundary condition. After having developed the difficulties that appears when implementing timesplittingmethods, we propose a new way to enforce the traction boundary condition which improves the orderof convergence. Then we propose a new definition of the advective velocity C which is needed for the Orlanskiboundary condition. Our propositions are validated against multiple physical flows: flow over a backward facingstep, flow around a biffurcation, flow around an obstacle and several Poiseuille-Rayleigh-Bénard flows.

Advisors/Committee Members: Azaïez, Mejdi (thesis director), Glockner, Stéphane (thesis director).

Subjects/Keywords: Navier-Stokes; Méthodes de time-splitting; Condition limite de sortie; Condition limite de traction; Condition limite d’Orlanski; Navier-Stokes; Time-splitting methods; Outflow boundary condition; Traction boundary condition; Orlanski boundary condition

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APA (6^th Edition):

Poux, A. (2012). Conditions limites de sortie pour les méthodes de time-splitting appliquées aux équations Navier-Stokes : Outflow boundary conditions for time-splitting methods applied to Navier-Stokes equations. (Doctoral Dissertation). Université de Bordeaux I. Retrieved from http://www.theses.fr/2012BOR14656

Chicago Manual of Style (16^th Edition):

Poux, Alexandre. “Conditions limites de sortie pour les méthodes de time-splitting appliquées aux équations Navier-Stokes : Outflow boundary conditions for time-splitting methods applied to Navier-Stokes equations.” 2012. Doctoral Dissertation, Université de Bordeaux I. Accessed January 23, 2021. http://www.theses.fr/2012BOR14656.

MLA Handbook (7^th Edition):

Poux, Alexandre. “Conditions limites de sortie pour les méthodes de time-splitting appliquées aux équations Navier-Stokes : Outflow boundary conditions for time-splitting methods applied to Navier-Stokes equations.” 2012. Web. 23 Jan 2021.

Vancouver:

Poux A. Conditions limites de sortie pour les méthodes de time-splitting appliquées aux équations Navier-Stokes : Outflow boundary conditions for time-splitting methods applied to Navier-Stokes equations. [Internet] [Doctoral dissertation]. Université de Bordeaux I; 2012. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2012BOR14656.

Council of Science Editors:

Poux A. Conditions limites de sortie pour les méthodes de time-splitting appliquées aux équations Navier-Stokes : Outflow boundary conditions for time-splitting methods applied to Navier-Stokes equations. [Doctoral Dissertation]. Université de Bordeaux I; 2012. Available from: http://www.theses.fr/2012BOR14656

University of Cincinnati

9. Jayakumar, Vignesh. Finite Element Model Correlation with Experiment Focusing on Descriptions of Clamped Boundary Condition and Damping.

Degree: PhD, Engineering and Applied Science: Mechanical Engineering, 2020, University of Cincinnati

URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592171762884289

► A two-step approach is developed to build an FEM model of a clamped structure focusing on the boundary stiffness and damping definitions. The approach utilizes… (more)

▼ A two-step approach is developed to build an FEM model of a clamped structure focusing on the boundary stiffness and damping definitions. The approach utilizes FE model correlation with experimentally obtained modal parameter estimates to calibrate the model. Model calibration is first carried out in a free-free state to update the geometry, mass and material properties of the structure. The calibrated free-free model is then updated in two stages to include the boundary stiffness and damping for a clamped state. Stiffness is addressed first followed by damping. The stiffness is defined in terms of contact stiffness definitions in terms of normal and tangential stiffness at the boundary. Contact stiffness is determined by matching analytical and measured natural frequencies of the clamped built-up structure. Calibration is carried out in a mode-wise manner and the system response is calculated in the frequency domain in bands centered around each mode of interest.In the second step, the damping property of the structure is identified based on responses at resonance. The significance of spatial distribution of damping is studied by first developing an approach to include accurate spatial distribution in models based on intuitive knowledge of the location of damping and then using it to compare against models built with traditional damping models such as Rayleigh and modal damping. Accurate representation of spatial distribution of damping in FE models was observed to be not very important for lightly damped structures.The stiffness and damping modeling approaches developed were combined and demonstrated on a clamped steel beam. The calibrated model is then validated by demonstrating its ability to make accurate strain predictions to arbitrary load cases. Random broadband and banded chirp loads were both used to compare the system responses from simulation and testing. Simulated FRF from calibrated system and the force spectra of interest are used to obtain the frequency domain response predictions. To obtain the time domain response an IFFT was used. Good agreement was observed between the response predicted in this manner and the one measured using the experimental setup. Advisors/Committee Members: Kim, Jay (Committee Chair).

Subjects/Keywords: Mechanical Engineering; Clamped boundary condition; FE-Test correlation; Model updating; Spatial distribution of damping; Boundary condition modeling; Damping modeling

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APA (6^th Edition):

Jayakumar, V. (2020). Finite Element Model Correlation with Experiment Focusing on Descriptions of Clamped Boundary Condition and Damping. (Doctoral Dissertation). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592171762884289

Chicago Manual of Style (16^th Edition):

Jayakumar, Vignesh. “Finite Element Model Correlation with Experiment Focusing on Descriptions of Clamped Boundary Condition and Damping.” 2020. Doctoral Dissertation, University of Cincinnati. Accessed January 23, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592171762884289.

MLA Handbook (7^th Edition):

Jayakumar, Vignesh. “Finite Element Model Correlation with Experiment Focusing on Descriptions of Clamped Boundary Condition and Damping.” 2020. Web. 23 Jan 2021.

Vancouver:

Jayakumar V. Finite Element Model Correlation with Experiment Focusing on Descriptions of Clamped Boundary Condition and Damping. [Internet] [Doctoral dissertation]. University of Cincinnati; 2020. [cited 2021 Jan 23]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592171762884289.

Council of Science Editors:

Jayakumar V. Finite Element Model Correlation with Experiment Focusing on Descriptions of Clamped Boundary Condition and Damping. [Doctoral Dissertation]. University of Cincinnati; 2020. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592171762884289

Penn State University

10. Wu, Xiaojie. Model Reduction by Dirichlet-to-Neumann map for Molecular Dynamics and Quantum Mechanics.

Degree: 2018, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/15697xxw139

► This dissertation studies model reduction techniques in the context of classical molecular dynamics and quantum mechanical models. Both the spatial and temporal reductions are considered.… (more)

▼ This dissertation studies model reduction techniques in the context of classical molecular dynamics and quantum mechanical models. Both the spatial and temporal reductions are considered. The model reduction is formulated as the Dirichlet-to-Neumman (DtN) map. In this dissertation, we restrict ourself into the systems where the number of degrees of freedoms is overwhelming, but the systems exihibit periodic structures, such as, lattice structure in crystalline solids or finite difference structure of the Laplace operator. In these special cases, we are able to take the advantage of the periodic structure, and evaluate the DtN map efficiently. The full model is reduced to a problem on the boundary of the computational domain. The main numerical tool used to compute the DtN map is the boundary element method. Since the lattice Green's function is computable for the system with the periodic structure, the boundary element method is practical. The boundary element method not only is crucial to static problems, where we seek the mechanical equilibirum, but also plays an important role in wave propagation problems. In wave propagation problems, the reduced model is the problem in a truncated domain with absorbing boundary conditions. The approximation of the dynamic DtN map provides such absorbing boundary condition. In this case, the stability of the reduced model must be ensured. The stability requirements will be presented. The same ansatz is applied to time-dependent Schrödinger equation and the time-dependent Hartree-Fock equation. For continuous equations, we start from the discretized model by finite difference. The periodic structure of the nodal points are mathematically equivalent to the lattice structure. Lattice Green's function and the DtN map can be computed using a similar approach. Stable approximations will be presented. This approach can be naturally extended to the time-dependent Hartree-Fock equation when the potential is neglectable in the exterior region. The idea of model reduction is verified by several numerical experiments: fracture in atomistic model, phonons propagation in molecular dynamics, one-dimensional time-dependent Schrödinger equation, and ¹⁶O+¹⁶O colisions. Advisors/Committee Members: Xiantao Li, Dissertation Advisor/Co-Advisor, Xiantao Li, Committee Chair/Co-Chair, Ludmil Zikatanov, Committee Member, Wenrui Hao, Committee Member, Long-Qing Chen, Outside Member, Francesco Costanzo, Outside Member.

Subjects/Keywords: Molecular Dynamics; Absorbing boundary condition; Hartree-Fock method; Model reduction; Boundary element method; Wave propagation

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APA (6^th Edition):

Wu, X. (2018). Model Reduction by Dirichlet-to-Neumann map for Molecular Dynamics and Quantum Mechanics. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/15697xxw139

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wu, Xiaojie. “Model Reduction by Dirichlet-to-Neumann map for Molecular Dynamics and Quantum Mechanics.” 2018. Thesis, Penn State University. Accessed January 23, 2021. https://submit-etda.libraries.psu.edu/catalog/15697xxw139.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wu, Xiaojie. “Model Reduction by Dirichlet-to-Neumann map for Molecular Dynamics and Quantum Mechanics.” 2018. Web. 23 Jan 2021.

Vancouver:

Wu X. Model Reduction by Dirichlet-to-Neumann map for Molecular Dynamics and Quantum Mechanics. [Internet] [Thesis]. Penn State University; 2018. [cited 2021 Jan 23]. Available from: https://submit-etda.libraries.psu.edu/catalog/15697xxw139.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wu X. Model Reduction by Dirichlet-to-Neumann map for Molecular Dynamics and Quantum Mechanics. [Thesis]. Penn State University; 2018. Available from: https://submit-etda.libraries.psu.edu/catalog/15697xxw139

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Connecticut

11. Sinsky, Eric Zachary. The Impacts of Surface Conditions on Sea Breezes over Coastal Connecticut.

Degree: MS, Oceanography, 2016, University of Connecticut

URL: https://opencommons.uconn.edu/gs_theses/906

► Sea breezes are mesoscale atmospheric coastal circulations that develop in response to diurnal variations in the land-sea thermal gradient resulting in cooler air temperatures… (more)

▼ Sea breezes are mesoscale atmospheric coastal circulations that develop in response to diurnal variations in the land-sea thermal gradient resulting in cooler air temperatures in coastal regions. Accurate numerical model hindcasts and forecasts of sea breezes, used to study and predict these circulations, are important for a variety of communities beyond the atmospheric sciences. For example, sea breezes can influence marine processes such as oceanic upwelling, estuarine circulation, and air-sea fluxes, as well as impact the energy, aviation, and air quality industries. Representations of the coastline and sea surface temperature (SST) in the numerical model can influence simulated sea breezes. In this study, a series of sensitivity experiments are performed to highlight the impact of the horizontal resolution of the numerical coastline and SST on simulated sea breeze dynamics. The 21 August 2013 and 08 July 2013 coastal CT sea breeze events are simulated using the Weather and Research Forecasting (WRF) model, initialized with the 32 km North American Regional Reanalysis (NARR) for atmospheric conditions. Coastline sensitivity experiments compare simulated sea breeze circulations using a coastline resolved at 32 km (O(NARR)) and 1 km (O(WRF)). Sea surface temperature sensitivity experiments compare a spatially uniform SST (22˚C), NARR (32 km) spatially varying SST, and the G1SST (1km) spatially varying SST. Coastline sensitivity experiments illustrate the use of a relatively coarse representation of the coastal geography results in the mischaracterization of western Long Island Sound as land, resulting in an inaccurate land-sea temperature gradient and thus an inaccurate sea breeze circulation. Sea breeze circulations are less sensitive to the resolution of the offshore SST, though the inland propagation distance of the sea breeze front varies among the sensitivity experiments. While the surface fluxes respond to the varying SST products, the impact on the overlying air temperature is confined to the lowest 100 m of the marine atmospheric boundary layer due to the relatively high stability limiting vertical mixing. Advisors/Committee Members: James Edson, Michael Whitney, Kelly Lombardo.

Subjects/Keywords: sea breeze; numerical modeling; sea temperature; surface boundary condition; marine atmospheric boundary layer

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APA (6^th Edition):

Sinsky, E. Z. (2016). The Impacts of Surface Conditions on Sea Breezes over Coastal Connecticut. (Masters Thesis). University of Connecticut. Retrieved from https://opencommons.uconn.edu/gs_theses/906

Chicago Manual of Style (16^th Edition):

Sinsky, Eric Zachary. “The Impacts of Surface Conditions on Sea Breezes over Coastal Connecticut.” 2016. Masters Thesis, University of Connecticut. Accessed January 23, 2021. https://opencommons.uconn.edu/gs_theses/906.

MLA Handbook (7^th Edition):

Sinsky, Eric Zachary. “The Impacts of Surface Conditions on Sea Breezes over Coastal Connecticut.” 2016. Web. 23 Jan 2021.

Vancouver:

Sinsky EZ. The Impacts of Surface Conditions on Sea Breezes over Coastal Connecticut. [Internet] [Masters thesis]. University of Connecticut; 2016. [cited 2021 Jan 23]. Available from: https://opencommons.uconn.edu/gs_theses/906.

Council of Science Editors:

Sinsky EZ. The Impacts of Surface Conditions on Sea Breezes over Coastal Connecticut. [Masters Thesis]. University of Connecticut; 2016. Available from: https://opencommons.uconn.edu/gs_theses/906

University of Manchester

12. Yang, Xue. Neumann problems for second order elliptic operators with singular coefficients.

Degree: PhD, 2012, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/neumann-problems-for-second-order-elliptic-operators-with-singular-coefficients(2e65b780-df58-4429-89df-6d87777843c8).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553550

► In this thesis, we prove the existence and uniqueness of the solution to a Neumann boundary problem for an elliptic differential operator with singular coefficients,… (more)

Subjects/Keywords: 536.2; Dirichlet form; Neumann boundary problem; Heat kernel; Fukushima's decomposition; Mixed boundary condition; Reflecting diffusion

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APA (6^th Edition):

Yang, X. (2012). Neumann problems for second order elliptic operators with singular coefficients. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/neumann-problems-for-second-order-elliptic-operators-with-singular-coefficients(2e65b780-df58-4429-89df-6d87777843c8).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553550

Chicago Manual of Style (16^th Edition):

Yang, Xue. “Neumann problems for second order elliptic operators with singular coefficients.” 2012. Doctoral Dissertation, University of Manchester. Accessed January 23, 2021. https://www.research.manchester.ac.uk/portal/en/theses/neumann-problems-for-second-order-elliptic-operators-with-singular-coefficients(2e65b780-df58-4429-89df-6d87777843c8).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553550.

MLA Handbook (7^th Edition):

Yang, Xue. “Neumann problems for second order elliptic operators with singular coefficients.” 2012. Web. 23 Jan 2021.

Vancouver:

Yang X. Neumann problems for second order elliptic operators with singular coefficients. [Internet] [Doctoral dissertation]. University of Manchester; 2012. [cited 2021 Jan 23]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/neumann-problems-for-second-order-elliptic-operators-with-singular-coefficients(2e65b780-df58-4429-89df-6d87777843c8).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553550.

Council of Science Editors:

Yang X. Neumann problems for second order elliptic operators with singular coefficients. [Doctoral Dissertation]. University of Manchester; 2012. Available from: https://www.research.manchester.ac.uk/portal/en/theses/neumann-problems-for-second-order-elliptic-operators-with-singular-coefficients(2e65b780-df58-4429-89df-6d87777843c8).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553550

University of Illinois – Urbana-Champaign

13. Kim, Kun Woo. New results in stochastic moving boundary problems.

Degree: PhD, 0439, 2012, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/31954

► Moving boundary problems arise in many areas of science and engineering and they are of great importance in the areas of partial differential equations (PDEs)… (more)

▼ Moving boundary problems arise in many areas of science and engineering and they are of great importance in the areas of partial differential equations (PDEs) since they characterize phase change phenomena where a system has two phases such as solid and liquid. However, unlike other PDEs in a prescribed region such as heat equation on a bounded domain, moving boundary problems are difficult to solve theoretically or numerically since we consider partial differential equations in one or two phases and at the same time need to trace the positions of the interface. Thus, they provide deep mathematical challenges. There is a vast literature on deterministic moving boundary problems. In addition, random perturbations of partial differential equations (e.g. stochastic heat equations) have been studied extensively. However, there has not been much attention paid to random perturbations of moving boundary problems. In this thesis, we consider random perturbations of two kinds of one-dimensional moving boundary problems: the Stefan problem, which describes the melting of the ice, and a free boundary problem proposed by Ludford and Stewart and studied by Caffarelli and Vazquez. In the first part, we consider a one-dimensional Stefan problem perturbed by a multiplicative noise. The noise is Brownian in time but smoothly correlated in space. We first define a weak solution then transform this problem into a nonlinear stochastic partial differential equation (SPDE) with a fixed boundary condition. We characterize the domain of existence and prove existence and uniqueness of a solution. The second part deals with a random perturbation of a moving boundary problem proposed by Ludford and Stewart and studied by Cafferelli and Vazquez. The random perturbation is a single Brownian motion and the moving boundary condition is different from the Stefan boundary condition. We consider existence and uniqueness of a solution and focus on numerical analysis of the problem. As for the stochastic Stefan problem, we use the transformation which transforms the stochastic moving boundary problem to a nonlinear SPDE which has a fixed spatial domain. Our numerical approximations are based on the nonlinear transformed SPDE. We use the explicit finite difference method and the Euler-Maruyama scheme to discretize time and space respectively. We also investigate the convergence theory. Advisors/Committee Members: Sowers, Richard B. (advisor), Song, Renming (Committee Chair), Sowers, Richard B. (committee member), DeVille, Robert E. (committee member), Namachchivaya, N. Sri (committee member).

Subjects/Keywords: Stochastic partial differential equations; stochastic moving boundary value problem; the Stefan boundary condition

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APA (6^th Edition):

Kim, K. W. (2012). New results in stochastic moving boundary problems. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/31954

Chicago Manual of Style (16^th Edition):

Kim, Kun Woo. “New results in stochastic moving boundary problems.” 2012. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 23, 2021. http://hdl.handle.net/2142/31954.

MLA Handbook (7^th Edition):

Kim, Kun Woo. “New results in stochastic moving boundary problems.” 2012. Web. 23 Jan 2021.

Vancouver:

Kim KW. New results in stochastic moving boundary problems. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2012. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2142/31954.

Council of Science Editors:

Kim KW. New results in stochastic moving boundary problems. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2012. Available from: http://hdl.handle.net/2142/31954

University of California – Riverside

14. Long, Gongbo. A Combined Boundary Integral Method for Crack Problems in Multilayered Elastic Media Under the Plane Strain Condition.

Degree: Mechanical Engineering, 2013, University of California – Riverside

URL: http://www.escholarship.org/uc/item/0wx7g5sj

► The crack problems in multilayered elastic media are of considerable interest in many engineering applications, particularly in hydraulic fracturing treatments for increasing hydrocarbon production. Various… (more)

Subjects/Keywords: Mechanical engineering; boundary integral method; multilayered elastic media; plane strain condition

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APA (6^th Edition):

Long, G. (2013). A Combined Boundary Integral Method for Crack Problems in Multilayered Elastic Media Under the Plane Strain Condition. (Thesis). University of California – Riverside. Retrieved from http://www.escholarship.org/uc/item/0wx7g5sj

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Long, Gongbo. “A Combined Boundary Integral Method for Crack Problems in Multilayered Elastic Media Under the Plane Strain Condition.” 2013. Thesis, University of California – Riverside. Accessed January 23, 2021. http://www.escholarship.org/uc/item/0wx7g5sj.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Long, Gongbo. “A Combined Boundary Integral Method for Crack Problems in Multilayered Elastic Media Under the Plane Strain Condition.” 2013. Web. 23 Jan 2021.

Vancouver:

Long G. A Combined Boundary Integral Method for Crack Problems in Multilayered Elastic Media Under the Plane Strain Condition. [Internet] [Thesis]. University of California – Riverside; 2013. [cited 2021 Jan 23]. Available from: http://www.escholarship.org/uc/item/0wx7g5sj.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Long G. A Combined Boundary Integral Method for Crack Problems in Multilayered Elastic Media Under the Plane Strain Condition. [Thesis]. University of California – Riverside; 2013. Available from: http://www.escholarship.org/uc/item/0wx7g5sj

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Mississippi State University

15. Borse, Manish Rajendra. Turbulent simulations of feline aortic flow under hypertrophic cardiomyopathy heart condition.

Degree: MS, Mechanical Engineering, 2016, Mississippi State University

URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06132016-143055/ ;

► A computational fluid dynamics (CFD) model is developed for pulsatile flows and particle transport to evaluate the possible thrombus trajectory in the feline aorta… (more)

Subjects/Keywords: Dean vortices; hair pin structures; vortical stuctures; iterative boundary condition; HCM

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APA (6^th Edition):

Borse, M. R. (2016). Turbulent simulations of feline aortic flow under hypertrophic cardiomyopathy heart condition. (Masters Thesis). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-06132016-143055/ ;

Chicago Manual of Style (16^th Edition):

Borse, Manish Rajendra. “Turbulent simulations of feline aortic flow under hypertrophic cardiomyopathy heart condition.” 2016. Masters Thesis, Mississippi State University. Accessed January 23, 2021. http://sun.library.msstate.edu/ETD-db/theses/available/etd-06132016-143055/ ;.

MLA Handbook (7^th Edition):

Borse, Manish Rajendra. “Turbulent simulations of feline aortic flow under hypertrophic cardiomyopathy heart condition.” 2016. Web. 23 Jan 2021.

Vancouver:

Borse MR. Turbulent simulations of feline aortic flow under hypertrophic cardiomyopathy heart condition. [Internet] [Masters thesis]. Mississippi State University; 2016. [cited 2021 Jan 23]. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06132016-143055/ ;.

Council of Science Editors:

Borse MR. Turbulent simulations of feline aortic flow under hypertrophic cardiomyopathy heart condition. [Masters Thesis]. Mississippi State University; 2016. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06132016-143055/ ;

Virginia Commonwealth University

16. Hosseini, Seyed Alireza. MODELING PARTICLE FILTRATION AND CAKING IN FIBROUS FILTER MEDIA.

Degree: PhD, Mechanical and Nuclear Engineering, 2011, Virginia Commonwealth University

URL: https://doi.org/10.25772/TKNV-5G24 ; https://scholarscompass.vcu.edu/etd/2530

► This study is aimed at developing modeling methodologies for simulating the flow of air and aerosol particles through fibrous filter media made up of micro-… (more)

▼ This study is aimed at developing modeling methodologies for simulating the flow of air and aerosol particles through fibrous filter media made up of micro- or nano-fibers. The study also deals with modeling particle deposition (due to Brownian diffusion, interception, and inertial impaction) and particle cake formation, on or inside fibrous filters. By computing the air flow field and the trajectory of airborne particles in 3-D virtual geometries that resemble the internal microstructure of fibrous filter media, pressure drop and collection efficiency of micro- or nano-fiber filters are simulated and compared with the available experimental studies. It was demonstrated that the simulations conducted in 3-D disordered fibrous domains, unlike previously reported 2-D cell-model simulations, do not need any empirical correction factors to closely predict experimental observations. This study also reports on the importance of fibers’ cross-sectional shape for filters operating in slip (nano-fiber filters) and no-slip (micro-fiber filters) flow regimes. In particular, it was found that the more streamlined the fiber geometry, the lower the fiber drag caused by a nanofiber relative to that generated by its micron-sized counterpart. This work also presents a methodology for simulating pressure drop and collection efficiency of a filter medium during instantaneous particle loading using the Fluent CFD code, enhanced by using a series of in-house subroutines. These subroutines are developed to allow one to track particles of different sizes, and simulate the formation of 2-D and 3-D dendrite particle deposits in the presence of aerodynamic slip on the surface of the fibers. The deposition of particles on a fiber and the previously deposited particles is made possible by developing additional subroutines, which mark the cells located at the deposition sites and modify their properties to so that they resemble solid or porous particles. Our unsteady-state simulations, in qualitative agreement with the experimental observations reported in the literature, predict the rate of increase of pressure drop and collection efficiency of a filter medium as a function of the mass of the loaded particles. Advisors/Committee Members: Hooman Tafreshi.

Subjects/Keywords: CFD; Filtration; Nano fiber; Slip boundary condition; Engineering

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APA (6^th Edition):

Hosseini, S. A. (2011). MODELING PARTICLE FILTRATION AND CAKING IN FIBROUS FILTER MEDIA. (Doctoral Dissertation). Virginia Commonwealth University. Retrieved from https://doi.org/10.25772/TKNV-5G24 ; https://scholarscompass.vcu.edu/etd/2530

Chicago Manual of Style (16^th Edition):

Hosseini, Seyed Alireza. “MODELING PARTICLE FILTRATION AND CAKING IN FIBROUS FILTER MEDIA.” 2011. Doctoral Dissertation, Virginia Commonwealth University. Accessed January 23, 2021. https://doi.org/10.25772/TKNV-5G24 ; https://scholarscompass.vcu.edu/etd/2530.

MLA Handbook (7^th Edition):

Hosseini, Seyed Alireza. “MODELING PARTICLE FILTRATION AND CAKING IN FIBROUS FILTER MEDIA.” 2011. Web. 23 Jan 2021.

Vancouver:

Hosseini SA. MODELING PARTICLE FILTRATION AND CAKING IN FIBROUS FILTER MEDIA. [Internet] [Doctoral dissertation]. Virginia Commonwealth University; 2011. [cited 2021 Jan 23]. Available from: https://doi.org/10.25772/TKNV-5G24 ; https://scholarscompass.vcu.edu/etd/2530.

Council of Science Editors:

Hosseini SA. MODELING PARTICLE FILTRATION AND CAKING IN FIBROUS FILTER MEDIA. [Doctoral Dissertation]. Virginia Commonwealth University; 2011. Available from: https://doi.org/10.25772/TKNV-5G24 ; https://scholarscompass.vcu.edu/etd/2530

University of Manchester

17. Pakle, Sagar. Near-wall boundary condition for LES.

Degree: 2011, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128680

► This study concerns with the new technique of enforcement of boundary conditions for LES in near wall region. The new approximate boundary condition which have… (more)

Subjects/Keywords: Approximate boundary condition; Turbulent flow; Large Eddy Simulations

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APA (6^th Edition):

Pakle, S. (2011). Near-wall boundary condition for LES. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128680

Chicago Manual of Style (16^th Edition):

Pakle, Sagar. “Near-wall boundary condition for LES.” 2011. Doctoral Dissertation, University of Manchester. Accessed January 23, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128680.

MLA Handbook (7^th Edition):

Pakle, Sagar. “Near-wall boundary condition for LES.” 2011. Web. 23 Jan 2021.

Vancouver:

Pakle S. Near-wall boundary condition for LES. [Internet] [Doctoral dissertation]. University of Manchester; 2011. [cited 2021 Jan 23]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128680.

Council of Science Editors:

Pakle S. Near-wall boundary condition for LES. [Doctoral Dissertation]. University of Manchester; 2011. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128680

18. Nania, Samantha Lynn. Spectroscopic analysis of molecular fluids at the solid-liquid interface.

Degree: PhD, Chemistry, 2017, University of Iowa

URL: https://ir.uiowa.edu/etd/5972

► Chemical and physical interactions play important roles in surface film formation and fluid slip at the fluid-solid interface. It has been shown that the… (more)

▼ Chemical and physical interactions play important roles in surface film formation and fluid slip at the fluid-solid interface. It has been shown that the fluid molecules at this solid interface behave differently than the molecules in the bulk. To investigate fluid film formation and the fluid’s transition between bulk and interfacial regions, a dynamic wetting technique is utilized. This technique allows the formation of variable thickness fluid films. When used in conjunction with vibrational spectroscopy and ellipsometry, direct analysis of variable thicknesses films, spanning the bulk to interfacial transition, can be obtained. Film thickness are predicted using the Landau-Levich model and the Lifshitz model, and comparisons generally agree with experimental results. According to hydrodynamic no slip boundary condition, fluid molecules near a solid surface can have no velocity with respect to the solid substrate. Recent theories state more specifically that, if a fluid comes in contact with an ultra-smooth surface (< 5-7 nm RMS roughness), the no slip boundary condition might be violated. We confirmed violation of the no slip boundary condition in two specific cases for fluid layers on SAM-modified substrates. To understand how the fluid/solid properties affect this condition, an acetophenone and bare silver surface was studied. Our results show that the structure and ordering of fluid molecules within these films are highly dependent on the film’s thickness and confinement. Temperature control wetting studies also corroborate with these results showing that as a frozen film of large thickness approaches the melting point, a molecular reorganization occurs creating a crystalline structure before the film melts into an isotropic bulk structure. Structure dependence on alkyl-chain length was then investigated using a series of trialkylamine fluids. Results show significant changes in the vibrational profile as a function of film thicknesses and rotational velocity as the alkyl-chains increase in length. These are ascribed to changes in primary carbon attached to the nitrogen as a function shearing and the rigidity of the molecule. These results reveal interactions taking place at the solid-liquid interface and have impacts on a broad spectrum of industrial, commercial, and research applications including lubrication and transportation vehicles. Advisors/Committee Members: Shaw, Scott K. (supervisor).

Subjects/Keywords: boundary condition; films; molecular fluids; ordering; surfaces; wetting; Chemistry

12 more images…

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APA (6^th Edition):

Nania, S. L. (2017). Spectroscopic analysis of molecular fluids at the solid-liquid interface. (Doctoral Dissertation). University of Iowa. Retrieved from https://ir.uiowa.edu/etd/5972

Chicago Manual of Style (16^th Edition):

Nania, Samantha Lynn. “Spectroscopic analysis of molecular fluids at the solid-liquid interface.” 2017. Doctoral Dissertation, University of Iowa. Accessed January 23, 2021. https://ir.uiowa.edu/etd/5972.

MLA Handbook (7^th Edition):

Nania, Samantha Lynn. “Spectroscopic analysis of molecular fluids at the solid-liquid interface.” 2017. Web. 23 Jan 2021.

Vancouver:

Nania SL. Spectroscopic analysis of molecular fluids at the solid-liquid interface. [Internet] [Doctoral dissertation]. University of Iowa; 2017. [cited 2021 Jan 23]. Available from: https://ir.uiowa.edu/etd/5972.

Council of Science Editors:

Nania SL. Spectroscopic analysis of molecular fluids at the solid-liquid interface. [Doctoral Dissertation]. University of Iowa; 2017. Available from: https://ir.uiowa.edu/etd/5972

Univerzitet u Beogradu

19. Vidaković, Barbara M. Побољшање ЦФД модела развоја пожара у тунелу на основу експерименталних података.

Degree: Mašinski fakultet, 2013, Univerzitet u Beogradu

URL: https://fedorabg.bg.ac.rs/fedora/get/o:6026/bdef:Content/get

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Машинство - Процесна техника / Мechanical engineering - Process Engineering

У овој дисертацији, посвећеној проблематици математичког описивања процеса развоја пожара у тунелу коришћењем експерименталних података,… (more)

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Машинство - Процесна техника / Мechanical engineering - Process Engineering

У овој дисертацији, посвећеној проблематици математичког описивања процеса развоја пожара у тунелу коришћењем експерименталних података, приказан је поступак кориговања пакета ЦФД (CFD) модела, у делу који се односи на дефинисање граничних услова за горуће површине. Кориговањем комплексног пакета CFD модела, који се састоји од спрегнутих „ k  “ модела турбулентних напона, модела великих вртлога, модела топлотног зрачења - тзв. модел дискретних ордината и модела сагоревања - тзв. модела устаљених ламинарних пламенова, омогућено је да се тачније опишу и предвиде збивања процеса сагоревања, која се остварују при овој врсти сложеног, неизотропног и турбулентног струјања гасова у тунелу. Детаљном анализим и поређењем експериметалних и нумерчких резултата, кроз сагледавање физичке суштине свих процеса који утичу на сагоревање, уочено је да основни пакет ЦФД модела, процес сагоревања нумерички поједностављено своди на процес мешања, а без могућности да обухвати појаву локалног недостака кисеоника, тј. моделира готово непосредну зависност између процеса мешња гасова и ослобођене количине топлоте у процесу сагоревања. Корекцијом модела у делу дефинисања граничниог услова за горућу површ, успостављањем директне корелације између измерене вредности брзине промене масе горива и ослобођене количине топлоте са горуће површине, избегнуто је не само улажење у сложене стехиометриске процесе сагоревања, него и избегнут потенцијано могући недостатак стандарног ЦФД пакета модела. Иако се основана разлика у квалитету предвиђања основног и унапређеног модела може најпрегледније сагледати спровођењем престављеног „ 2  “теста, квaлитативно значaјно побољшање уочљиво је и кроз непосредно поређење промене температуре гасова на мерним местима изнад и низводно од пламена. Уочљиво је да промена температуре гасова у коригованом моделу, на само изражено у бројним вредностима, него и по карактеру криве, даје далеко боља предвиђања од основног модела. VII

Advisors/Committee Members: Genić, Srbislav, 1963-.

Subjects/Keywords: fire; tunnel fire; CFD modelling; boundary condition; turbulence modelling

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APA (6^th Edition):

Vidaković, B. M. (2013). Побољшање ЦФД модела развоја пожара у тунелу на основу експерименталних података. (Thesis). Univerzitet u Beogradu. Retrieved from https://fedorabg.bg.ac.rs/fedora/get/o:6026/bdef:Content/get

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Vidaković, Barbara M. “Побољшање ЦФД модела развоја пожара у тунелу на основу експерименталних података.” 2013. Thesis, Univerzitet u Beogradu. Accessed January 23, 2021. https://fedorabg.bg.ac.rs/fedora/get/o:6026/bdef:Content/get.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Vidaković, Barbara M. “Побољшање ЦФД модела развоја пожара у тунелу на основу експерименталних података.” 2013. Web. 23 Jan 2021.

Vancouver:

Vidaković BM. Побољшање ЦФД модела развоја пожара у тунелу на основу експерименталних података. [Internet] [Thesis]. Univerzitet u Beogradu; 2013. [cited 2021 Jan 23]. Available from: https://fedorabg.bg.ac.rs/fedora/get/o:6026/bdef:Content/get.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Vidaković BM. Побољшање ЦФД модела развоја пожара у тунелу на основу експерименталних података. [Thesis]. Univerzitet u Beogradu; 2013. Available from: https://fedorabg.bg.ac.rs/fedora/get/o:6026/bdef:Content/get

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Cambridge

20. Petrie, Owen. Linear and weakly nonlinear boundary layer acoustics in a lined duct.

Degree: PhD, 2020, University of Cambridge

URL: https://www.repository.cam.ac.uk/handle/1810/298785

► In this thesis I look at the effect of boundary layer flow on the acoustics of an acoustic lining. Acoustic linings are used in aircraft… (more)

Subjects/Keywords: acoustics; aeroacoustics; duct acoustics; nonlinear acoustics; impedance boundary condition

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APA (6^th Edition):

Petrie, O. (2020). Linear and weakly nonlinear boundary layer acoustics in a lined duct. (Doctoral Dissertation). University of Cambridge. Retrieved from https://www.repository.cam.ac.uk/handle/1810/298785

Chicago Manual of Style (16^th Edition):

Petrie, Owen. “Linear and weakly nonlinear boundary layer acoustics in a lined duct.” 2020. Doctoral Dissertation, University of Cambridge. Accessed January 23, 2021. https://www.repository.cam.ac.uk/handle/1810/298785.

MLA Handbook (7^th Edition):

Petrie, Owen. “Linear and weakly nonlinear boundary layer acoustics in a lined duct.” 2020. Web. 23 Jan 2021.

Vancouver:

Petrie O. Linear and weakly nonlinear boundary layer acoustics in a lined duct. [Internet] [Doctoral dissertation]. University of Cambridge; 2020. [cited 2021 Jan 23]. Available from: https://www.repository.cam.ac.uk/handle/1810/298785.

Council of Science Editors:

Petrie O. Linear and weakly nonlinear boundary layer acoustics in a lined duct. [Doctoral Dissertation]. University of Cambridge; 2020. Available from: https://www.repository.cam.ac.uk/handle/1810/298785

Delft University of Technology

21. Belier, Joris (author). Wave Dynamics in Inverse Krylov Subspaces.

Degree: 2019, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:e12eb0e2-67a2-4640-8598-3f639f12cea4

► Recent studies have shown an increased interest in modal solutions of wave problems with resonating structures. These studies demonstrate that resonating structures with physical dimensions… (more)

▼ Recent studies have shown an increased interest in modal solutions of wave problems with resonating structures. These studies demonstrate that resonating structures with physical dimensions close to a wavelength can be accurately described by a few relevant resonating modes. The physical dimensions of the demonstrated resonating structures were close to a wavelength, which suggests that these highly-resonating modes have relatively low eigenvalues. Those resonating-modes are therefore dominantly present in Krylov subspaces generated by inverse projections of the wave-operator. Relevant wave dynamics can, therefore, be effectively computed from inverse Krylov subspaces. Furthermore, inverse Krylov subspaces are computationally stable and are therefore a powerful way to compute high-fidelity modal solutions. With interesting applications in high Q-factor wave problems. The aim of this work is on improving the performance of inverse Krylov subspaces. Improvements to inverse Krylov subspace can be grouped into two approaches. In the first approach symmetry is exploited in the inverse wave-operator for reduced computational complexity and in the second approach the wave-operator is conditioned for desirable characteristics at the relatively low side of the spectrum. We will study several wave-operator configurations and optimize according to those approaches. Earlier studies have shown that in the dimensions with pseudo-periodic boundary conditions, the double-curl is efficiently eigendecomposed as spatial derivatives are diagonal operators acting on frequency representations. We extend this work by providing an alternative, more compact presentation in the continuous domain of the eigendecomposition of the double-curl. This eigendecomposition is used to create a nullspace free eigenvalue problem. Consecutively, we analyse the characteristics of the inverse wave-operator with Perfectly Matched Layers (PML). This analysis shows that in terms of inverse Krylov subspaces, the PML is not the obvious choice for the optimal absorbing boundary condition. Most notably, the PML introduces undesirable effects at the lower end of the spectrum, significantly impeding the performance of inverse Krylov subspaces, which leads to the conclusion that absorbing boundary conditions should be reassessed in terms of inverse Krylov subspaces behaviour. Lastly, we will study the so-called Fixed-Frequency PML (FF-PML), which is a PML inspired time-independent absorbing boundary condition. Our study has shown that the FF-PML is a more suitable absorbing boundary condition candidate for inverse Krylov subspaces. It does not have the undesirable effects at the lower end of the spectrum, which the traditional PML has. Furthermore, and even more importantly, we derive analytic expressions of the inverse wave operator with FF-PML absorbing boundary conditions. This simple and novel insight is easily exploited to invert the wave-operator efficiently, which enables a new approach to the computation of modal solutions of open scattering problems. The… Advisors/Committee Members: Remis, Rob (mentor), Delft University of Technology (degree granting institution).

Subjects/Keywords: Wave simulation; Reduced order model; Krylov; Modes; Periodic boundary condition; PML

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APA (6^th Edition):

Belier, J. (. (2019). Wave Dynamics in Inverse Krylov Subspaces. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:e12eb0e2-67a2-4640-8598-3f639f12cea4

Chicago Manual of Style (16^th Edition):

Belier, Joris (author). “Wave Dynamics in Inverse Krylov Subspaces.” 2019. Masters Thesis, Delft University of Technology. Accessed January 23, 2021. http://resolver.tudelft.nl/uuid:e12eb0e2-67a2-4640-8598-3f639f12cea4.

MLA Handbook (7^th Edition):

Belier, Joris (author). “Wave Dynamics in Inverse Krylov Subspaces.” 2019. Web. 23 Jan 2021.

Vancouver:

Belier J(. Wave Dynamics in Inverse Krylov Subspaces. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 23]. Available from: http://resolver.tudelft.nl/uuid:e12eb0e2-67a2-4640-8598-3f639f12cea4.

Council of Science Editors:

Belier J(. Wave Dynamics in Inverse Krylov Subspaces. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:e12eb0e2-67a2-4640-8598-3f639f12cea4

University of Waterloo

22. Ali Asghar, Ameli. Semi-analytical methods for simulating the groundwater-surface water interface.

Degree: 2014, University of Waterloo

URL: http://hdl.handle.net/10012/8703

► Groundwater-surface water interaction is a key component of the hydrologic cycle. This interaction plays a key role in many environmental issues such as the impacts… (more)

▼ Groundwater-surface water interaction is a key component of the hydrologic cycle. This interaction plays a key role in many environmental issues such as the impacts of land use and climate change on water availability and water quality. Modeling of local and regional groundwater-surface water interactions improves understanding of these environmental issues and assists in addressing them. Because of the physical and mathematical complexities of this interaction, numerical approaches are generally used to model water exchange between subsurface and surface domains. The efficiency, accuracy, and stability of mesh-based numerical models, however, depend upon the resolution of the underlying grid or mesh. Grid-free analytical methods can provide fast, accurate, continuous and differentiable solutions to groundwater-surface water interaction problems. These solutions exactly satisfy mass balance in the entire internal domain and may improve our understanding of groundwater-surface water interaction principles. However, to model this interaction, analytical approaches typically required simplifying, sometimes unrealistic, assumptions. They are typically used to implement linearized mathematical models in homogenous confined or semi-confined aquifers with geometrically regular domains. By benefiting from the strengths of both analytical and numerical approaches, grid-free semi-analytical methods may be able to address more challenging groundwater problems which have been out of reach of traditional analytical approaches, and/or are poorly simulated using mesh-based numerical methods. Here, novel 2-D and 3-D semi-analytical solutions for the simulation of mathematically and physically complex groundwater-surface water interaction problems are developed, assessed and applied. Those models are based upon the series solution method and analytic element method (AEM) and are intended to address groundwater-surface water interactions induced by pumping wells and/or the presence of surface water bodies in naturally complex stratified unconfined aquifers. Semi-analytical solutions are obtained using the least squares method, which is used to determine the unknown coefficients in the series expansion and the unknown strengths of analytic elements. The series and AEM solutions automatically satisfy the groundwater governing equation. Hence, the resulting solutions are exact over the entire domain except along boundaries and layer interfaces where boundary and continuity conditions are met with high precision. A robust iterative algorithm is used to implement a free boundary condition along the phreatic surface with a priori unknown location. This thesis addresses three general problem types never addressed within a semi-analytic framework. First, a steady-state free boundary semi-analytical series solutions model is developed to simulate 2-D saturated-unsaturated flow in geometrically complex stratified unconfined aquifers. The saturated-unsaturated flow is controlled by water exchange along the land surface (e.g.,…

Subjects/Keywords: Ground water-Surface water interaction; Free boundary condition; Semi-Analytical method

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APA (6^th Edition):

Ali Asghar, A. (2014). Semi-analytical methods for simulating the groundwater-surface water interface. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/8703

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ali Asghar, Ameli. “Semi-analytical methods for simulating the groundwater-surface water interface.” 2014. Thesis, University of Waterloo. Accessed January 23, 2021. http://hdl.handle.net/10012/8703.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ali Asghar, Ameli. “Semi-analytical methods for simulating the groundwater-surface water interface.” 2014. Web. 23 Jan 2021.

Vancouver:

Ali Asghar A. Semi-analytical methods for simulating the groundwater-surface water interface. [Internet] [Thesis]. University of Waterloo; 2014. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10012/8703.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ali Asghar A. Semi-analytical methods for simulating the groundwater-surface water interface. [Thesis]. University of Waterloo; 2014. Available from: http://hdl.handle.net/10012/8703

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Cambridge

23. Petrie, Owen. Linear and weakly nonlinear boundary layer acoustics in a lined duct.

Degree: PhD, 2020, University of Cambridge

URL: https://doi.org/10.17863/CAM.45840 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.793061

► In this thesis I look at the effect of boundary layer flow on the acoustics of an acoustic lining. Acoustic linings are used in aircraft… (more)

Subjects/Keywords: acoustics; aeroacoustics; duct acoustics; nonlinear acoustics; impedance boundary condition

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Petrie, O. (2020). Linear and weakly nonlinear boundary layer acoustics in a lined duct. (Doctoral Dissertation). University of Cambridge. Retrieved from https://doi.org/10.17863/CAM.45840 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.793061

Chicago Manual of Style (16^th Edition):

Petrie, Owen. “Linear and weakly nonlinear boundary layer acoustics in a lined duct.” 2020. Doctoral Dissertation, University of Cambridge. Accessed January 23, 2021. https://doi.org/10.17863/CAM.45840 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.793061.

MLA Handbook (7^th Edition):

Petrie, Owen. “Linear and weakly nonlinear boundary layer acoustics in a lined duct.” 2020. Web. 23 Jan 2021.

Vancouver:

Petrie O. Linear and weakly nonlinear boundary layer acoustics in a lined duct. [Internet] [Doctoral dissertation]. University of Cambridge; 2020. [cited 2021 Jan 23]. Available from: https://doi.org/10.17863/CAM.45840 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.793061.

Council of Science Editors:

Petrie O. Linear and weakly nonlinear boundary layer acoustics in a lined duct. [Doctoral Dissertation]. University of Cambridge; 2020. Available from: https://doi.org/10.17863/CAM.45840 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.793061

24. -8221-3645. Subsurface elastic wave energy focusing based on a time reversal concept.

Degree: PhD, Civil Engineering, 2017, University of Texas – Austin

URL: http://hdl.handle.net/2152/61529

► In the context of wave propagation, time-reversal refers to the invariance of the wave equation when the direction of traversing the time line is reversed.… (more)

▼ In the context of wave propagation, time-reversal refers to the invariance of the wave equation when the direction of traversing the time line is reversed. To date, there have been several applications rooted in the time-reversal concept, primarily in acoustics and in electromagnetics, and in settings that typically involve closed, finite, domains. In recent times, the concept has been predominantly used for steering and focusing wave energy in medical therapeutics. The extension of the time-reversal concept to elastodynamics, particularly in unbounded domains, entails challenges: the presence of two velocities and two body wave types, the presence of surface waves, the unboundness of the host domain, and aperture constraints, all conspire to limit or weaken wave focusing. This dissertation concentrates on a computational study for assessing the feasibility of focusing elastic waves to one or multiple subsurface targets, based on the time-reversal concept. Of particular interest is the focusing of wave energy to subterranean geologic formations, embedded within heterogeneous hosts. The motivation stems from potential applications to wave-based enhanced oil recovery, though other applications also stand to benefit. We report on a study that systematically assesses each and every limitation that is present when a small number of surface motion records are time-reversed and broadcast back into a heterogenous halfspace, aimed at the illumination of subsurface targets. We report the results of numerical experiments in two and three dimensions, and the impact of the limitations on the focusing resolution. All in all, despite the difficulties imposed by the physical setting, we conclude that focusing of elastic wave energy is feasible and competitive when compared against inverse source methods with similar targeting or focusing goals. Advisors/Committee Members: Kallivokas, Loukas F (advisor), Fomel, Sergey B (committee member), Stokoe, Kenneth H (committee member), Demkowicz, Leszek F (committee member), Ghattas, Omar (committee member), Tassoulas, John L (committee member).

Subjects/Keywords: Wave focusing; Time-reversal; Wave propagation; PML; Absorbing boundary condition

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APA (6^th Edition):

-8221-3645. (2017). Subsurface elastic wave energy focusing based on a time reversal concept. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/61529

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Chicago Manual of Style (16^th Edition):

-8221-3645. “Subsurface elastic wave energy focusing based on a time reversal concept.” 2017. Doctoral Dissertation, University of Texas – Austin. Accessed January 23, 2021. http://hdl.handle.net/2152/61529.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

MLA Handbook (7^th Edition):

-8221-3645. “Subsurface elastic wave energy focusing based on a time reversal concept.” 2017. Web. 23 Jan 2021.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

-8221-3645. Subsurface elastic wave energy focusing based on a time reversal concept. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2017. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2152/61529.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Council of Science Editors:

-8221-3645. Subsurface elastic wave energy focusing based on a time reversal concept. [Doctoral Dissertation]. University of Texas – Austin; 2017. Available from: http://hdl.handle.net/2152/61529

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

25. Seo, Dongjin. Measurement and Control of Slip-Flow Boundary Conditions at Solid-Gas Interfaces.

Degree: PhD, Chemical Engineering, 2014, Virginia Tech

URL: http://hdl.handle.net/10919/50650

► This thesis describes measurements of the gas-solid flow boundary condition at moderate Knudsen number, i.e., where the dimensions of the flow are similar to the… (more)

▼ This thesis describes measurements of the gas-solid flow boundary condition at moderate Knudsen number, i.e., where the dimensions of the flow are similar to the mean free path, and thus partial slip is expected. This regime has become more important with increased focus on nano-scale devices, but there is currently no consensus on how the slip length should vary for different solids and gases, or whether it can be controlled. In this thesis, I describe unambiguous measurements showing that partial slip occurs, that the slip length depends both on gas and solid, and that the slip length can be altered in situ. The slip length is determined from analysis of the vibration of a small sphere adjacent to a solid. I also describe applications of these findings both to the separation of gases, and to inhalants. The effect of water films, gas species, organic films, and electric fields on gas flow was studied. Water films had a large, but complex effect. On bare hydrophobilic glass, the tangential momentum accommodation coefficient (TMAC) for nitrogen on hydroxyl-terminated silica changed from 0.25 to 0.88 when the humidity changed from 0 to 98 %. On hydrophobized glass, TMAC changed from 0.20 to 0.56 in the same range. The effect of the gas on TMAC was measured for five different gases (helium, nitrogen, argon, carbon dioxide, hexafluoride sulfur) on octadecyltrichlorosilane-coated glass surfaces. A lower TMAC occurred for greater molar mass, and this trend was explained using a simple model representing both the gas and the monolayer by spheres. The existence of this gas-dependent difference in TMAC suggests that gases can be separated based on their collisions with surfaces. Methods for controlling the flow boundary condition were also developed by adsorbing monolayers on the solid, and altering the monolayers in situ. Both temperature and electric fields altered the boundary condition, and these changes were attributed to changes in the surface roughness. The effect of roughness was modeled with grooved surfaces. Possible applications of this effect of roughness include changing the flow of aerosol droplets for deeper delivery of therapeutic drugs into the lung. Advisors/Committee Members: Ducker, William A. (committeechair), Martin, Stephen Michael (committee member), Paul, Mark R. (committee member), Davis, Richey M. (committee member).

Subjects/Keywords: gas; slip flow; accommodation coefficient; boundary condition; lubrication

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APA (6^th Edition):

Seo, D. (2014). Measurement and Control of Slip-Flow Boundary Conditions at Solid-Gas Interfaces. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/50650

Chicago Manual of Style (16^th Edition):

Seo, Dongjin. “Measurement and Control of Slip-Flow Boundary Conditions at Solid-Gas Interfaces.” 2014. Doctoral Dissertation, Virginia Tech. Accessed January 23, 2021. http://hdl.handle.net/10919/50650.

MLA Handbook (7^th Edition):

Seo, Dongjin. “Measurement and Control of Slip-Flow Boundary Conditions at Solid-Gas Interfaces.” 2014. Web. 23 Jan 2021.

Vancouver:

Seo D. Measurement and Control of Slip-Flow Boundary Conditions at Solid-Gas Interfaces. [Internet] [Doctoral dissertation]. Virginia Tech; 2014. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10919/50650.

Council of Science Editors:

Seo D. Measurement and Control of Slip-Flow Boundary Conditions at Solid-Gas Interfaces. [Doctoral Dissertation]. Virginia Tech; 2014. Available from: http://hdl.handle.net/10919/50650

Colorado School of Mines

26. Huang, Jingwei. Pore-scale simulation of multiphase flow using lattice Boltzmann method: developments and applications.

Degree: MS(M.S.), Petroleum Engineering, 2016, Colorado School of Mines

URL: http://hdl.handle.net/11124/170028

► Multiphase flow is an important transport process that is found in many natural phenomena and engineering applications. In petroleum engineering, sub-surface multiphase flow takes place… (more)

Subjects/Keywords: boundary condition; lattice Boltzmann; multiphase flow; parallel computing

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APA (6^th Edition):

Huang, J. (2016). Pore-scale simulation of multiphase flow using lattice Boltzmann method: developments and applications. (Masters Thesis). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/170028

Chicago Manual of Style (16^th Edition):

Huang, Jingwei. “Pore-scale simulation of multiphase flow using lattice Boltzmann method: developments and applications.” 2016. Masters Thesis, Colorado School of Mines. Accessed January 23, 2021. http://hdl.handle.net/11124/170028.

MLA Handbook (7^th Edition):

Huang, Jingwei. “Pore-scale simulation of multiphase flow using lattice Boltzmann method: developments and applications.” 2016. Web. 23 Jan 2021.

Vancouver:

Huang J. Pore-scale simulation of multiphase flow using lattice Boltzmann method: developments and applications. [Internet] [Masters thesis]. Colorado School of Mines; 2016. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/11124/170028.

Council of Science Editors:

Huang J. Pore-scale simulation of multiphase flow using lattice Boltzmann method: developments and applications. [Masters Thesis]. Colorado School of Mines; 2016. Available from: http://hdl.handle.net/11124/170028

27. Khalile, Magda. Problèmes spectraux avec conditions de Robin sur des domaines à coins du plan : Spectral problems with Robin boundary conditions on planar domains with corners.

Degree: Docteur es, Mathématiques appliquées, 2018, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2018SACLS235

►

Dans cette thèse, nous étudions les propriétés spectrales du Laplacien avec la condition de bord de Robin attractive sur des domaines du plan à coins.… (more)

Subjects/Keywords: Géometrie spectrale; Analyse asymptotique; Laplacien; Condition de bord de Robin; Coins; Spectral geometry; Asymptotic analysis; Laplacian; Robin boundary condition; Corners

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APA (6^th Edition):

Khalile, M. (2018). Problèmes spectraux avec conditions de Robin sur des domaines à coins du plan : Spectral problems with Robin boundary conditions on planar domains with corners. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2018SACLS235

Chicago Manual of Style (16^th Edition):

Khalile, Magda. “Problèmes spectraux avec conditions de Robin sur des domaines à coins du plan : Spectral problems with Robin boundary conditions on planar domains with corners.” 2018. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 23, 2021. http://www.theses.fr/2018SACLS235.

MLA Handbook (7^th Edition):

Khalile, Magda. “Problèmes spectraux avec conditions de Robin sur des domaines à coins du plan : Spectral problems with Robin boundary conditions on planar domains with corners.” 2018. Web. 23 Jan 2021.

Vancouver:

Khalile M. Problèmes spectraux avec conditions de Robin sur des domaines à coins du plan : Spectral problems with Robin boundary conditions on planar domains with corners. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2018. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2018SACLS235.

Council of Science Editors:

Khalile M. Problèmes spectraux avec conditions de Robin sur des domaines à coins du plan : Spectral problems with Robin boundary conditions on planar domains with corners. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2018. Available from: http://www.theses.fr/2018SACLS235

NSYSU

28. Lin, Jing-Hua. Application of Slip Velocity Boundary Condition to Estimate Waves induced Bed Velocity and Bed Shear Stress.

Degree: PhD, Marine Environment and Engineering, 2013, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0115113-151817

► In the present study, a new and simple method for determining the slip velocity (also called the bed velocity) on the solid-fluid interface in the… (more)

▼ In the present study, a new and simple method for determining the slip velocity (also called the bed velocity) on the solid-fluid interface in the wave boundary layer is proposed. Based on experimental and numerical results, when waves travel over a rigid permeable seabed, a nonzero slip velocity exists at the solid-fluid interface. The defect of a small slip velocity has been found to occur in previous studies and is usually encountered in fluid-porous layer problems. In the wave-rigid permeable seabed problem, the slip effect depends on the properties of the seabed. The slip velocity boundary condition (SVBC) is one specification of the slip conditions and is usually applied to explain the slip phenomenon in a fluid-porous layer problem. However, the traditional SVBC or the slip velocity is only considered in a single flow, and the application of SVBC in harmonic motion is still an open problem that necessitates a simple formula for determining the slip velocity in realistic cases. The Stokesâ second problem and the slip length model (SLM) are applied to derive a new slip velocity and a slip factor in this paper. Both the permeability and the roughness of the seabed are chosen as the characteristic length of slip motion. The analytical solution shows that the new slip velocity depends on the wave period and the pressure gradient, and the slip factor is related to the wave Reynolds number, the permeability, and the roughness of the seabed. The resultant slip velocity shows good agreement with the experimental results. Using the slip factor to determine the bed shear stress in the laminar/turbulent-rough regimes is the second part in this study. A simple relationship is developed to theoretically estimate the wave friction factor in various flow regimes in the porous media based on the slip factor formula. The theoretical formula shows that the wave friction factor varies inversely with the relative bed roughness,A/ks , over a rough bed and that it can be conveniently determined if wave conditions and sediment parameters are known without using a specific regression formula deduced from experiments. A laboratory experiment that directly measures the wave-driven bed shear stress dominant in the turbulent regime with a permeable bed is used to examine the newly-derived relationship. In the laminar regime, the comparison demonstrates that the theoretical results determined by the proposed formula are in good agreement with existing measurements. In the turbulent-rough regime, the influence of eddy viscosity is considered in the present model and the zero-equation model is used to estimate an average eddy viscosity. The theoretical wave friction factor is reasonably close to the experimental measurement, and considerably better than that obtained by other existing regressions. It is also found that the wave friction factor in the small zone can be described by the present model, with comparisons showing that the slip factor theory can be extended to estimate the wave friction factor in the turbulent-rough regime.… Advisors/Committee Members: Chung-Pan, Lee (chair), Tai-Wen, Hsu (chair), Hwung-Hweng, Hwung (chair), Yang-Yih, Chen (committee member), Guan-Yu, Chen (committee member), Ming-Chung, Lin (chair), Jaw-Fang, Lee (chair).

Subjects/Keywords: Slip factor; Bed slip velocity; Wave friction factor; Bed shear stress; Wave boundary layer; Slip length model; Slip velocity boundary condition

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lin, J. (2013). Application of Slip Velocity Boundary Condition to Estimate Waves induced Bed Velocity and Bed Shear Stress. (Doctoral Dissertation). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0115113-151817

Chicago Manual of Style (16^th Edition):

Lin, Jing-Hua. “Application of Slip Velocity Boundary Condition to Estimate Waves induced Bed Velocity and Bed Shear Stress.” 2013. Doctoral Dissertation, NSYSU. Accessed January 23, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0115113-151817.

MLA Handbook (7^th Edition):

Lin, Jing-Hua. “Application of Slip Velocity Boundary Condition to Estimate Waves induced Bed Velocity and Bed Shear Stress.” 2013. Web. 23 Jan 2021.

Vancouver:

Lin J. Application of Slip Velocity Boundary Condition to Estimate Waves induced Bed Velocity and Bed Shear Stress. [Internet] [Doctoral dissertation]. NSYSU; 2013. [cited 2021 Jan 23]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0115113-151817.

Council of Science Editors:

Lin J. Application of Slip Velocity Boundary Condition to Estimate Waves induced Bed Velocity and Bed Shear Stress. [Doctoral Dissertation]. NSYSU; 2013. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0115113-151817

Vilnius University

29. Kaulakytė, Kristina. Nonhomogeneous boundary value problem for the stationary Navier-Stokes system in domains with noncompact boundaries.

Degree: Dissertation, Mathematics, 2013, Vilnius University

URL: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081640-17274 ;

►

In the thesis there is studied nonhomogenous boundary value problem for the stationary Navier-Stokes system in domains which may have two types of outlets to… (more)

Subjects/Keywords: Navier-Stokes system; Noncompact boundary; Nonhomogeneous boundary condition; Navjė-Stokso sistema; Nekompaktiškas kraštas; Nehomogeninė kraštinė sąlyga

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kaulakytė, K. (2013). Nonhomogeneous boundary value problem for the stationary Navier-Stokes system in domains with noncompact boundaries. (Doctoral Dissertation). Vilnius University. Retrieved from http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081640-17274 ;

Chicago Manual of Style (16^th Edition):

Kaulakytė, Kristina. “Nonhomogeneous boundary value problem for the stationary Navier-Stokes system in domains with noncompact boundaries.” 2013. Doctoral Dissertation, Vilnius University. Accessed January 23, 2021. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081640-17274 ;.

MLA Handbook (7^th Edition):

Kaulakytė, Kristina. “Nonhomogeneous boundary value problem for the stationary Navier-Stokes system in domains with noncompact boundaries.” 2013. Web. 23 Jan 2021.

Vancouver:

Kaulakytė K. Nonhomogeneous boundary value problem for the stationary Navier-Stokes system in domains with noncompact boundaries. [Internet] [Doctoral dissertation]. Vilnius University; 2013. [cited 2021 Jan 23]. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081640-17274 ;.

Council of Science Editors:

Kaulakytė K. Nonhomogeneous boundary value problem for the stationary Navier-Stokes system in domains with noncompact boundaries. [Doctoral Dissertation]. Vilnius University; 2013. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081640-17274 ;

Vilnius University

30. Kaulakytė, Kristina. Stacionari Navjė-Stokso sistema su nehomogenine kraštine sąlyga srityse su nekompaktiškais kraštais.

Degree: PhD, Mathematics, 2013, Vilnius University

URL: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081649-62168 ;

►

Disertacijoje nagrinėjama stacionari Navjė-Stokso sistema su nehomogenine kraštine sąlyga srityse su išėjimais į begalybę. Bendru atveju išėjimai į begalybę gali būti tiek paraboloidiniai, tiek sluoksnio… (more)

Subjects/Keywords: Navjė-Stokso sistema; Nekompaktiškas kraštas; Nehomogeninė kraštinė sąlyga; Navier-Stokes system; Noncompact boundary; Nonhomogeneous boundary condition

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kaulakytė, K. (2013). Stacionari Navjė-Stokso sistema su nehomogenine kraštine sąlyga srityse su nekompaktiškais kraštais. (Doctoral Dissertation). Vilnius University. Retrieved from http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081649-62168 ;

Chicago Manual of Style (16^th Edition):

Kaulakytė, Kristina. “Stacionari Navjė-Stokso sistema su nehomogenine kraštine sąlyga srityse su nekompaktiškais kraštais.” 2013. Doctoral Dissertation, Vilnius University. Accessed January 23, 2021. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081649-62168 ;.

MLA Handbook (7^th Edition):

Kaulakytė, Kristina. “Stacionari Navjė-Stokso sistema su nehomogenine kraštine sąlyga srityse su nekompaktiškais kraštais.” 2013. Web. 23 Jan 2021.

Vancouver:

Kaulakytė K. Stacionari Navjė-Stokso sistema su nehomogenine kraštine sąlyga srityse su nekompaktiškais kraštais. [Internet] [Doctoral dissertation]. Vilnius University; 2013. [cited 2021 Jan 23]. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081649-62168 ;.

Council of Science Editors:

Kaulakytė K. Stacionari Navjė-Stokso sistema su nehomogenine kraštine sąlyga srityse su nekompaktiškais kraštais. [Doctoral Dissertation]. Vilnius University; 2013. Available from: http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130124_081649-62168 ;

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