Fluid Dynamics Commons^™

Parameter Identifiability And Estimation In A 1d Cardiovascular Fluid Dynamics Model, Mitchel J. Colebank

Biology and Medicine Through Mathematics Conference

No abstract provided.

Parameter Estimation For Tear Film Thinning, Rayanne Luke

Biology and Medicine Through Mathematics Conference

No abstract provided.

The Siltcatcher: A Sediment-Capture System For Wetland Creation And Coastal Protection In Western Lake Pontchartrain, Andrew M. Wright

LSU Master's Theses

The West Lake Pontchartrain region faces a number of long-term environmental challenges due to anthropogenic climate disturbance and landscape modification, including sea level rise, increased storm surge risk, shoreline erosion, and wetland degradation. In response, this thesis applies recent research in the fields of landscape architecture and civil engineering to propose a dynamic, natural-systems solution for wetland creation and shoreline protection. The project envisions a series of breakwater-like structures in western Lake Pontchartrain positioned to slow water released from the nearby Bonnet Carré Spillway, causing suspended sediment to settle and create self-building and self-sustaining wetlands capable of keeping pace with ...

Studies Of Oval Tube And Fin Heat Exchangers, Phillip Nielsen

Discovery Day - Prescott

Heating Ventilation and air-conditioning (HVAC) is a system which changes the temperature of the surroundings for the purposes of cooling or heating. This system requires energy to maintain a temperature difference from the outside temperature. This is important since minimized power is one of the requirements for the system to achieve a better efficiency. Optimizing the flow over the evaporator coils is one way to increase the cooling efficiency. This will reduce the power required to have a sustainable system. Optimizing the flow to increase the energy transfer between the fins and the incoming air could result in a greater ...

Characterization Of Magma Storage And Dynamics At Akutan, Semisopochnoi, And Okmok Volcanoes From Analytical And Numerical Models Of Geodetic, Seismic, And Petrologic Data, Kimberly Degrandpre

Earth Sciences Theses and Dissertations

Volcanic eruptions can cause significant socioeconomic loss, but a better understanding of the processes and dynamics influencing the evolution of volcanic plumbing systems will advance the development of eruption forecasting models that will ultimately mitigate hazards and risks associated with eruptive events. Geologic and geophysical data must be integrated in 3D, finite- element, multiphysical, numerical models to define the coupled evolution of magmatic and crustal stress regimes in volcanic environments, but in data limited regions this is not always an option. The remote nature of the Aleutian Island Arc restricts ground-based monitoring and sampling efforts, and due to sparse temporal ...

1d Fluid Model Of Rf-Excited Cold Atmospheric Plasmas In Helium With Air Gas Impurities, Yifan Liu, Dingxin Liu, Jishen Zhang, Bowen Sun, Aijun Yang, Michael G. Kong

Bioelectrics Publications

Cold atmospheric plasmas (CAPs) in helium with air gas impurities (HeþAir for abbreviation) compromise the discharge stability of helium and the chemical reactivity of air, having great prospects for various applications such as plasma biomedicine. However, different kinds of reactive species are produced in HeþAir CAPs but only a few of them could be measured, and the plasma chemistry is so complex that the reported simulation models are simplified to a large extent, such as neglecting the space variation of CAPs by using a 0D model. As a result, much remains unknown for HeþAir CAPs, which hinders the development of ...

Swirling Fluid Flow In Flexible, Expandable Elastic Tubes: Variational Approach, Reductions And Integrability, Rossen Ivanov, Vakhtang Putkaradze

Articles

Many engineering and physiological applications deal with situations when a fluid is moving in flexible tubes with elastic walls. In real-life applications like blood flow, a swirl in the fluid often plays an important role, presenting an additional complexity not described by previous theoretical models. We present a theory for the dynamics of the interaction between elastic tubes and swirling fluid flow. The equations are derived using a variational principle, with the incompressibility constraint of the fluid giving rise to a pressure-like term. In order to connect this work with the previous literature, we consider the case of inextensible and ...

Developing A Uas-Deployable Methane Sensor Using Low-Cost Modular Open-Source Components, Gavin Demali

Williams Honors College, Honors Research Projects

This project aimed to develop a methane sensor for deployment on an unmanned aerial system (UAS), or drone, platform. This design is centered around low cost, commercially available modular hardware components and open source software libraries. Once successfully developed, this system was deployed at the Bath Nature Preserve in Bath Township, Summit County Ohio in order to detect any potential on site fugitive methane emissions in the vicinity of the oil and gas infrastructure present. The deliverables of this project (i.e. the data collected at BNP) will be given to the land managers there to better inform future management ...

Numerical And Semi-Analytical Estimation Of Convective Heat Transfer Coefficient For Buildings In An Urban-Like Setting, Anwar Demsis Awol

Electronic Thesis and Dissertation Repository

Urban building arrangements such as packing density, orientation and size are known to influence the microclimate surrounding each building. Studies on the impact of urban microclimatic changes on convective heat transfer coefficient (CHTC) from a stock of buildings, however, have been rare in surveyed literature. The present study focuses on numerical and analytical investigation of CHTC from building-like models with homogeneous set of equal and unequal planar and frontal densities. Consequently, the study discusses the CHTC response in relation to broader changes in the urban surface form. Part of the process involves the development of a simplified one-dimensional semi-analytical CHTC ...

Residual Stress Models For Large Eddy Simulation Of Stratified Turbulent Flows, Felipe Augusto Ventura De Bragança Alves

Doctoral Dissertations

The residual stresses and scalar fluxes are required to close the momentum and scalar transport equations in simulations of turbulence that are not fully resolved in space.

In stratified turbulence, the stress and fluxes are statistically anisotropic unless the smallest resolved length scale is smaller than the Ozmidov scale and the buoyancy Reynolds number is sufficiently high for there to exist a range of scales that is statistically isotropic.

In this work, a tensorial basis set is derived analytically that potentially contains sufficient information about the anisotropic interaction between resolved and residual scales.

The residual stress tensor is evaluated by ...

Characterization Of Single- And Multi-Phase Shock-Accelerated Flows, Patrick John Wayne

Mechanical Engineering ETDs

Experiments conducted in the Shock Tube Facility at the University of New Mexico are focused on characterization of shock-accelerated flows. Single-phase (gaseous) initial conditions consist of a heavy gas column of sulfur hexafluoride seeded with approximately 11% acetone gas by mass. Visualization of the image plane for gaseous initial conditions is accomplished via planar laser-induced fluorescence (PLIF) with a high-powered Nd:YAG ultraviolet laser and an Apogee Alta U-42 monochrome CCD camera, with a quantum efficiency > 90%. Multi-phase (gas-solid) initial conditions consist of glass micro-beads deposited on small 1-cm diameter discs of specific surface chemistry, mounted flush with the bottom ...

A Study On Homogeneous Sheared Stably Stratified Turbulence, Gavin Portwood

Doctoral Dissertations

Homogeneous sheared and stably stratified turbulence is considered as a fundamental flow relevant to the study of geophysical turbulence and, generally, anisotropic turbulence. Numerical experiments are performed via high resolution direct numerical simulation (DNS) in a geophysically-relevant parameter space previously inaccessible to simulation. Turbulent dynamics relevant to the modeling of geophysical hydrodynamics are investigated as a function of mean flow and fluid parameters.

An active tuning scheme is implemented to induce temporally stationary turbulent kinetic energy in order to evaluate turbulence that is statistically independent of initial conditions and spatio-temporally homogeneous. Subject to this constraint, the parametric dependence of the ...

Flow-Induced Oscillations In Floating Offshore Wind Turbines, Daniel Carlson

Doctoral Dissertations

The goal of this thesis is to experimentally study the structural dynamics, wake interaction, and fluid forces on the multiple-degree of freedom systems typical of floating wind turbines. Vortex--surface alignment about flexibly-mounted prisms is studied to investigate the response of barges and semi-submersible hulls, and new results pertaining to the galloping response kink for a prism with dual inline--crossflow resonance is presented. Flow--induced oscillations of a spar model free to rotate in 3D space is replicated and observed as 2D figure--eight orbits about the center of the spar. Methods to suppress the flow from exciting the spar are proposed. The ...

A Quadrature-Based Moment Method For Polydisperse Bubbly Flows, Jeffrey C. Heylmun, Bo Kong, Alberto Passalacqua, Rodney O. Fox

Chemical and Biological Engineering Publications

A computational algorithm for polydisperse bubbly flow is developed by combining quadrature-based moment methods (QBMM) with an existing two-fluid solver for gas–liquid flows. Care is taken to ensure that the two-fluid model equations are hyperbolic by generalizing the kinetic model for the bubble phase proposed by Bieseuvel and Gorissen (1990). The kinetic formulation for the bubble phase includes the full suite of interphase momentum exchange terms for bubbly flow, as well as ad hoc bubble–bubble interaction terms to model the transition from isolated bubbles to regions of pure air at very high bubble-phase volume fractions. A robust numerical ...

Fluid Transport In Porous Media For Engineering Applications, Eric M. Benner

Chemical and Biological Engineering ETDs

This doctoral dissertation presents three topics in modeling fluid transport through porous media used in engineering applications. The results provide insights into the design of fuel cell components, catalyst and drug delivery particles, and aluminum- based materials. Analytical and computational methods are utilized for the modeling of the systems of interest. Theoretical analysis of capillary-driven transport in porous media show that both geometric and evaporation effects significantly change the time dependent behavior of liquid imbibition and give a steady state flux into the medium. The evaporation–capillary number is significant in determining the time-dependent behavior of capillary flows in porous ...

High Resolution Validation Of Next Generation Turbulent Flow Models Using Neutron Beams, Laser Fluorescence, And Cryogenic Helium, Landen G Mcdonald

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Turbulent fluid flow is an incredibly unpredictable subject that continues to confound scientists and engineers. All of the empirical data that has been the basis of conventional turbulent computational fluid dynamics (CFD) models for decades only extends to roughly the equivalent turbulence created when Michael Phelps swims in a pool. The problem is that this data is then extrapolated out many orders of magnitude in order to design cruise ships, airplanes, and rockets which operate in significantly more turbulent flow regimes. This creates an incredible degree of uncertainty in the design process that demands over-engineering and increased expenditures.

The development ...

Geospatial Energy Potential And Life Cycle Assessment Of Nearshore Oscillating Water Column Systems, Aleks Siemenn, Marie-Odile Fortier

CURCE Annual Undergraduate Conference

Oscillating Water Column (OWC) systems are an iteration of terminator ocean energy technology which generate electrical energy from turbine torque induced by the compression of air in a chamber from changing water level height. OWCs are a well-established technology, however, there have been no studies to date which quantify the life cycle environmental impacts of these systems in a geographic context. The goal of this study is to optimally size an OWC system for selected New England coastline sites and then assess the environmental impacts of the varying system sizes.

An OWC system is optimally sized when the volume of ...

Modeling Multiphase Flow And Substrate Deformation In Nanoimprint Manufacturing Systems, Andrew Cochrane

Nanoscience and Microsystems ETDs

Nanopatterns found in nature demonstrate that macroscopic properties of a surface are tied to its nano-scale structure. Tailoring the nanostructure allows those macroscopic surface properties to be engineered. However, a capability-gap in manufacturing technology inhibits mass-production of nanotechnologies based on simple, nanometer-scale surface patterns. This gap represents an opportunity for research and development of nanoimprint lithography (NIL) processes. NIL is a process for replicating patterns by imprinting a fluid layer with a solid, nano-patterned template, after which ultraviolet cure solidifies the fluid resulting in a nano-patterned surface. Although NIL has been demonstrated to replicate pattern features as small as 4 ...

Implementation Of Fast Hydraulic Erosion Simulation And Visualization On Gpu, Brian Hawkins

Computer Science Graduate Research Workshop

No abstract provided.

Quantification Of Contrast-Enhanced Ultrasound, Joseph Pathoulas

All College Thesis Program, 2016-2019

The aim of this experiment was to investigate the effect of manipulating ultrasound scanner settings on time-intensity curve parameters in a tube perfusion phantom system using contrast-enhanced ultrasound imaging. Imaging was performed using a Philips LOGIQ E9 ultrasound scanner equipped with a C1-6VN transducer and utilized two different microbubble contrast agents: Definity and Lumason. The ultrasound scanner settings manipulated included: gain, dynamic range, and frequency. Additionally, relative microbubble concentration, microbubble type, and perfusion flow rate were manipulated. Four time-intensity curve parameters (time to peak, area under curve, gradient, peak intensity) were measured from linearized pixel data. Time to peak was ...