Search Constraints

Start Over
Filtering by: Subject Fluid dynamics -- Mathematical models Remove constraint Subject: Fluid dynamics -- Mathematical models Rights Statement In Copyright Remove constraint Rights Statement: In Copyright

Search Results

  • Winter cover cropping effects on integrative biological indicators of soil quality

    Creator:
    Ndiaye, Evelyne L.
    Abstract:
    Responses of biological indicators of soil quality to winter cover cropping were measured on soil samples collected from 6 commercial growers' fields and two experiment research stations in the Willamette Valley of Oregon. The research stations were the North Willamette Research and Extension Center (Aurora, OR), and the Oregon State...
    Resource Type:
    Masters Thesis
    Full Text:
    organic matter but it is a dynamic, living component that is involved in various biogeochemical

  • Using a single-well push-pull test to estimate mass transfer rate parameters

    Creator:
    Kelley, Michael John
    Abstract:
    More efficient methods are needed for the in-situ evaluation of mass transfer parameters which describe the movement of solutes through aquifer material. The objective of this study was to develop a method for estimating diffusion rate and capacity coefficients using a single-well, "push-pull" tracer test. The method consists of the...
    Resource Type:
    Masters Thesis
    Full Text:
    2.4 Mathematical Model 22 3. PHYSICAL AQUIFER MODF.T. (PAM) 27 3.1 Overview and Background

  • Hybrid Multiscale Methods with Applications to Semiconductors, Porous Media, and Materials Science

    Creator:
    Costa, Timothy B.
    Abstract:
    In this work we consider two multiscale applications with tremendous computational complexity at the lower scale. First, we examine a model for charge transport in semicon- ductor structures with heterojunction interfaces. Due to the complex physical phenomena at the interface, the model at the design scale is unable to adequately...
    Resource Type:
    Dissertation
    Full Text:
    decomposition methods that decouple the interface computation from the macroscale model. For the fluid flow

  • A numerical study of inertial flow features in moderate Reynolds number flow through packed beds of spheres

    Creator:
    Finn, Justin Richard
    Abstract:
    In this work, flow through synthetic arrangements of contacting spheres is studied as a model problem for porous media and packed bed type flows. Direct numerical simulations are performed for moderate pore Reynolds numbers in the range, 10 ≤ Re ≤ 600, where non-linear porescale flow features are known to...
    Resource Type:
    Dissertation
    Full Text:
    contacting spheres is studied as a model problem for porous media and packed bed type flows. Direct numeri

  • A numerical model of drop-on demand droplet formation from a vibrating nozzle and a rigid nozzle

    Creator:
    Yang, Guozhong
    Abstract:
    Droplet formation from a rigid and a vibration nozzle driven by a pulsing pressure is simulated. Droplet formation is simulated by using one-dimensional model. For the case of droplet formation from a vibration nozzle, the nozzle vibration is simulated by large deflection plate vibration equation. Droplet formation from a rigid...
    Resource Type:
    Masters Thesis
    Full Text:
    model and marker-and-cell front tracking technique. The fluid was considered as incompressible. He

  • Interactions of a fully modulated inclined jet with a crossflow

    Creator:
    Dano, Bertrand P. E.
    Abstract:
    Jets in crossflow are used in a wide range of engineering applications and have been studied for more than 60 years. The transversal penetration and structure of a jet placed in a crossflow is known to be strongly three-dimensional. It is believed that, by using a pulsed jet inclined in...
    Resource Type:
    Dissertation
    Full Text:
    environmental release of gases and fumes in the atmosphere. Blowing a stream of fluid in a crossflow typically

  • Numerical study of droplet formation with nozzle dynamics and multiple droplet impingement

    Creator:
    Sangplung, Saangrut
    Abstract:
    Droplet formation from a flexible nozzle plate driven by a prescribed-waveform excitation of a piezoelectric is numerically investigated using a computational fluid dynamics (CFD) model with the VOF method. The droplet generator with a flexible nozzle plate, which is free to vibrate due to the pressure acting on the plate,...
    Resource Type:
    Dissertation
    Full Text:
    pertinent topics. The mathematical model of fluid flow model, nonlinear large deflection plate equations

  • Quantifying linear disturbance growth in periodic and aperiodic systems

    Creator:
    Wolfe, Christopher Lee
    Abstract:
    The mathematical and physical connections between three different ways of quantifying linear predictability in geophysical fluid systems are studied in a series of analytical and numerical models. Normal modes, as they are traditionally formulated in the instabilities theories of geophysical fluid dynamics, characterize the asymptotic development of disturbances to stationary...
    Resource Type:
    Dissertation
    Full Text:
    Disturbance Growth in Periodic and Aperiodic Systems Abstract approved: Roger M. Samelson The mathematical

  • Interpolation Schemes for Two Dimensional Flow with Applications

    Creator:
    Umhoefer, Joseph G.
    Abstract:
    In this thesis we study a numerical analysis problem motivated by the need to simulate an event such as an oil spill in a deep water environment. Numerical simulation can help to mitigate the disastrous effects of such events by aiding the management of risk assessment and recovery efforts. However,...
    Resource Type:
    Masters Thesis
    Full Text:
    algorithms that provide a smooth field from given discrete data. The Blowout and Spill Occurrence Model

  • An experimental study and a three-dimensional numerical wave basin model of solitary wave impact on a vertical cylinder

    Creator:
    Zhang, Wenbin
    Abstract:
    An experiment on solitary wave impact on a vertical cylinder was conducted in the three-dimensional wave basin at the Oregon State University Hinsdale Wave Research Laboratory. The cylinder was designed using mechanic principles and finite element analysis techniques to enable accurate measurement of horizontal force and overturning moment. Video data...
    Resource Type:
    Masters Thesis
    Full Text:
    Lagrangian-Eulerian (ALE) option for the fluid to model full-scale fluid-structure interaction laboratory

  • Prediction of Initial Mixing for Municipal Ocean Discharges

    Creator:
    Teeter, Allan M. and Baumgartner, D. J.
    Abstract:
    The purpose of this report is to present procedures by which applicants and reviewers can calculate initial dilution and describe the zone of initial dilution surrounding the discharge site. These calculations would be required under regulations proposed by the U.S. Environmental Protection Agency on April 25, 1978 (1) implementing section...
    Resource Type:
    Capstone Project
    Full Text:
    unconfined environments. Sotil (17) posed a mathematical model for slot jets or continuous line sources in

  • On the effects of centrifugal forces in air-water two-phase flow regime transitions of an adiabatic helical geometry

    Creator:
    Young, Eric P.
    Abstract:
    Two-phase flow in helical conduits is important in many industries where reaction between components, heat transfer, and mass transport are utilized as processes. The helical design is chosen for the effects of secondary flow patterns that reduce axial dispersion, increased heat transfer, and also their compact design. The first is...
    Resource Type:
    Dissertation
    Full Text:
    . . . . . . . . . . . . . . . . . 10 1.3.2 Drift Flux Model . . . . . . . . . . . . . . . . . . . . . . . . . 11 1.3.3 Two Fluid

  • Stochastic analysis of flow and transport in porous media

    Creator:
    Vasylkivska, Veronika S.
    Abstract:
    Random fields are frequently used in computational simulations of real-life processes. In particular, in this work they are used in modeling of flow and transport in porous media. Porous media as they arise in geological formations are intrinsically deterministic but there is significant uncertainty involved in determination of their properties...
    Resource Type:
    Dissertation
    Full Text:
    appreciate the fact that I didn’t need to write the deterministic solvers for model problems since they were

  • RANS and LES predictions of turbulent scalar transport in dead zones of natural streams

    Creator:
    Drost, Kevin J.
    Abstract:
    Natural stream systems contain a variety of flow geometries which contain flow separation, turbulent shear layers, and recirculation zones. This work focuses on streams with dead zones. Characterized by slower flow and recirculation, dead zones are naturally occurring cutouts in stream banks. These dead zones play an important role in...
    Resource Type:
    Masters Thesis
    Full Text:
    zone. Using these fluid quantities and a simplified model of the dead zone, the residence time could

  • An analysis of wave forces on prototype walls under tsunami loading

    Creator:
    Oshnack, Mary Elizabeth
    Abstract:
    This thesis is comprised of two manuscripts based on a laboratory experiment conducted to examine realistic wave forcing on a vertical wall subjected to tsunami loading. The first manuscript examined tsunami force and pressure distributions on a rigid wall that was fronted by a small seawall. Six different seawall heights...
    Resource Type:
    Masters Thesis
    Full Text:
    the fluid-structure interaction. This work was conducted in the Large Wave Flume adjacent to the

  • Three Topics on Coastal Hazards : Propagation, Transformation, and Impact

    Creator:
    Ko, Harrison T.
    Abstract:
    An understanding of natural coastal hazards is essential for improving resilience of coastal communities. Effective management of coastal hazards relies on prediction tools and mitigation structures that have been designed to handle the dynamic coastal system. This dissertation is a collection of manuscripts that cover a diverse range of fundamental...
    Resource Type:
    Dissertation
    Full Text:
    to handle the dynamic coastal system. This dissertation is a collection of manuscripts that cover a

  • A novel lattice Boltzmann method for treatment of multicomponent convection, diffusion, and reaction phenomena in multiphase systems

    Creator:
    Parker, James Muirhead
    Abstract:
    In this work, a multicomponent lattice Boltzmann model is developed for the simulation of multiphase mixing, reactions, and separations processes. This model is unique in that diffusive mass transfer of a component in the model is driven by gradients of chemical potential. This fundamentally correct description of diffusion accurately captures...
    Resource Type:
    Dissertation
    Full Text:
    speed of fluid ci Molar concentration of species i cs Sound speed of the model cx Component in x

  • Detection and analysis of separated flow induced vortical structures

    Creator:
    Snider, Stephen David Louis
    Abstract:
    Flow separation is an important phenomenon in fluid dynamics because of the effect it has on lift and drag on immersed bodies. Areas of swirl within a separated flow region may have a distinct effect on the surface forces, modifying the lift and drag characteristics. A correlation between the passage...
    Resource Type:
    Masters Thesis
    Full Text:
    standard dynamic model, and a new one-equation dynamic model that they introduce. The predictions using

  • GPU-Based Fluid-Structure Interaction using Immersed Boundary Methods

    Creator:
    Minar, Christopher
    Abstract:
    Engineering applications often require fast, accurate solutions of fluid flow around freely moving bodies. The massive parallelism enabled by graphics processing unit (GPU) architecture enables high performance, offering a promising alternative to traditional solver acceleration via multicore central processing units (CPU). However, fully harnessing GPU parallelism requires specialized algorithms and...
    Resource Type:
    Masters Thesis
    Full Text:
    computing strategies. This work modifies direct-forcing immersed boundary methods to model fluid-structure

  • Modeling and simulation of volume displacement effects in multiphase flow

    Creator:
    Cihonski, Andrew John
    Abstract:
    There are many options available when selecting a computational model for two-phase flows. It is important to understand all the features of the model selected, including when the model is appropriate and how using it may affect your results. This work examines how volume displacement effects in two-phase Eulerian-Lagrangian models...
    Resource Type:
    Dissertation
    Full Text:
    level models are Eulerian-Eulerian, such as the two-fluid model in which both phases are treated as

  • Hydrodynamic contact/impact modeling and application to ocean engineering problems

    Creator:
    Challa, Ravi
    Abstract:
    Fluid-structure interaction (FSI) is a very interesting and challenging multi-disciplinary field involving interaction of a movable or deformable structure with an internal or surrounding fluid flow. FSI has several practical engineering applications such as the determination of the hydrodynamic forces on a structure or the dynamics of motion of bodies...
    Resource Type:
    Dissertation
    Full Text:
    Abstract approved: Solomon C. Yim Abstract: Fluid-structure interaction (FSI) is a very

  • Numerical simulation of cavitating bubble-laden turbulent flows

    Creator:
    Shams Sobhani, Ehsan
    Abstract:
    Many engineering devices and propulsion systems suffer from undesirable effects of cavitation; such as degradation in the efficiency of pumps and turbines, generation of noise and vibration on ship propeller, increased drag and erosion of propeller blade, etc. In spite of decades of research on this problem, detailed study of...
    Resource Type:
    Dissertation
    Full Text:
    unstructured grid finite volume solver. Large Eddy Simulation technique with dynamic Smagorinsky subgrid model

  • Itraconazole formation using supercritical carbon dioxide

    Creator:
    Tang, Yi-Min
    Resource Type:
    Masters Thesis
    Full Text:
    has the highest dissolution rate in gastric fluid. An intrinsic mathematical model was also

  • A multiscale modeling approach for bubble-vortex interactions in hydro-propulsion systems

    Creator:
    Finn, Justin Richard
    Abstract:
    Multiphase flow dynamics are important in many naval and turbomachinery applications, where bubble interaction with low pressure, vortical structures can lead to undesirable cavitation effects. To better understand the underlying phenomena, a multiscale numerical framework is developed to simulate bubble laden flow in dynamic hydro propulsion systems. Several subproblems in...
    Resource Type:
    Masters Thesis
    Full Text:
    model. Here, a single fluid phase is assumed, and the equations of fluid motion are solved along with a

  • Clearing bubble blockages in micro channels using a model predictive controller

    Creator:
    Patton, Chris
    Abstract:
    Micro scale systems are being utilized in a wide variety of chemical, biological and heat exchanger applications, but suffer from the development of vapor bubbles inside the microchannels due to convective boiling, leading to decreases in system performance. In this work, a simulation-based control strategy is employed to eliminate flow...
    Resource Type:
    Masters Thesis
    Full Text:
    performance degradation. In this work, a model of fluid flow through a parallel mi- crochannel geometry is

  • Scaling of the Chinese HTR-PM Reactor Design for Licensing and Testing at the Oregon State University High Temperature Test Facility

    Creator:
    Cox, Jordan
    Abstract:
    The United States (US) Department of Energy (DOE) has identified the pebble-bed reactor as a high priority for US research with the end goal of licensing a pebble-bed reactor (PBR) for operation in the United States. Before this can be accomplished significant research must be done regarding the safety of...
    Resource Type:
    Masters Thesis
    Full Text:
    that this facility could model heat transfer, temperature profiles, and fluid forces found in the

  • Hydroelastic modeling of a wave energy converter using the arbitrary Lagrangian-Eulerian finite element method in LS-DYNA

    Creator:
    Meicke, Stephen A.
    Abstract:
    This thesis investigates the applicability of the finite element method to model wave energy converter (WEC) hydroelasticity using LS-DYNA. The proposed methodology uses the Arbitrary Lagrangian-Eulerian formulation to model Fluid-Structure Interaction (FSI) between the WEC and the fluid elements. This formulation allows for time-domain modeling of higher order effects such...
    Resource Type:
    Masters Thesis
    Full Text:
    model Fluid-Structure Interaction (FSI) between the WEC and the fluid elements. This formulation

  • Fluid-structure interaction analysis with the particle finite element method

    Creator:
    Zhu, Minjie
    Abstract:
    To facilitate the evaluation and design of structures subjected to fluid loading, a study of fluid-structure interaction (FSI) using the particle finite element method (PFEM) is presented to approximate the responses and sensitivities of structures which interact with fluid. A wide range of structural types are permissible by making no...
    Resource Type:
    Dissertation
    Full Text:
    influenced. Therefore, it is crucial to accurately model the fluid and structural domains as well as the

  • Development of vehicle dynamics tools for motorsports

    Creator:
    Patton, Chris
    Abstract:
    In this dissertation, a group of vehicle dynamics simulation tools is developed with two primary goals: to accurately represent vehicle behavior and to provide insight that improves the understanding of vehicle performance. Three tools are developed that focus on tire modeling, vehicle modeling and lap time simulation. Tire modeling is...
    Resource Type:
    Dissertation
    Full Text:
    is extended to provide a flexible model structure that allows arbitrary inputs to be included. For

  • Numerical simulation of mechanically stabilized earth walls for parametric evaluation of behavior under surcharge loading

    Creator:
    Ambauen, Spencer J.
    Abstract:
    A numerical model, simulating the complex behavior of reinforced soil walls using the finite element method, was developed to evaluate the behavior of a surcharged, geosynthetic-reinforced retaining wall with modular block facing. A nonlinear elastic-plastic constitutive soil material model was calibrated to experimental plane strain test data, while the performance...
    Resource Type:
    Masters Thesis
    Full Text:
    . Leshchinsky A numerical model, simulating the complex behavior of reinforced soil walls using the

  • Tsunami-induced Soil Instability

    Creator:
    Fischer, Rachael Marie
    Abstract:
    Recent tsunami field surveys from the 2011 Great East Japan Earthquake and Tsunami have recorded numerous examples of tsunami-induced soil instability: significant scour around foundations, foundation failure of piles, and other damage caused by liquefaction. From the observations of soil instability leading to the failure of critical coastal structures, it...
    Resource Type:
    Masters Thesis
    Full Text:
    series taken from the Park et al (2014) ComMIT/MOST inundation model. Two onshore locations of

  • An approach to reduced-order modeling and feedback control for wave energy converters

    Creator:
    Shoori J., Hesam E.
    Abstract:
    Wave energy holds great promise to be part of the alternative energy portfolio that will provide independence from fossil fuels. As wave energy converter (WEC) technologies mature, designing effective control strategies to extract maximum energy, extend device life, coordinate WEC operation within an array, or mitigate negative impacts of a...
    Resource Type:
    Masters Thesis
    Full Text:
    applicability of a recently developed model reduction tech- nique, Balanced POD, applied to a WEC fluid

  • The effects of clouds on transient baroclinic eddies in a Mars General Circulation Model

    Creator:
    Rucker, Michael S.
    Abstract:
    The low-level baroclinic eddy activity seen in the NASA Ames Mars General Circulation Model (MGCM) for simulations under three annual dust cycles are characterized. Simulations were conducted with both radiatively active and radiatively inert clouds (RAC and non-RAC, respectively) for 11 continuous annual cycles for each dust case. Model results...
    Resource Type:
    Masters Thesis
    Full Text:
    Effects of Clouds on Transient Baroclinic Eddies in a Mars General Circulation Model Abstract approved

  • Simulating vegetation shifts and carbon cycling in Yosemite National Park

    Creator:
    Conklin, David R.
    Abstract:
    The vegetation in Yosemite National Park changed during the 20th century and may change in the 21st century in response to climate change. Vegetation surveys made during the 1930s and the 1990s provide benchmark records separated by 60 years. This study uses the MC1 dynamic global vegetation model to forecast...
    Resource Type:
    Dissertation
    Full Text:
    records separated by 60 years. This study uses the MC1 dynamic global vegetation model to forecast and

  • Multiscale analysis of saturated flow in a porous medium with an adjacent thin channel

    Creator:
    Morales, Fernando A.
    Abstract:
    This thesis contains three parts addressing the asymptotic analysis of fluid flow through fully saturated porous medium in the presence of an adjacent thin channel. In the first part the problem is modeled by Darcy's law in both the porous medium and in the channel. The permeability in the channel...
    Resource Type:
    Dissertation
    Full Text:
    fluid velocity in the channel, which is a more accurate model for the faster flow. The two laws have