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Flow

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Full-Text Articles in Engineering

Auto Adjustable Flow Regulator, Ethan Hemmerlin, Jack Dooley Mar 2024

Auto Adjustable Flow Regulator, Ethan Hemmerlin, Jack Dooley

Biomedical Engineering

The Auto-Adjustable Oxygen Flowmeter device is to be used in conjunction with an oxygen source or reservoir, as well as a low-flow nasal cannula apparatus. The device is applicable for patients requiring an oxygen flow rate of 0-6 L/min. Further, the device works to maintain a healthy blood-oxygen concentration of 90-94% for typical patients, as well as an 88-92% range for COPD patients who are chronic CO2 retainers. A reflective pulse oximeter will record the SpO2 concentration of the patient. The outputted SpO2 concentration will be transmitted to an internal processing PCB from which it will interact with the oxygen …


Travel Time Theory For Traffic Conservation Laws With Applications, Sergio Contreras Dec 2023

Travel Time Theory For Traffic Conservation Laws With Applications, Sergio Contreras

UNLV Theses, Dissertations, Professional Papers, and Capstones

Travel time is an important concept in various intelligent transportation system (ITS) applications. The concept is used in a wide array of applications, such as system planning, system performance, and optimization. Reducing the time required to travel between different points on a network is an important goal. Benefits include reducing time wasted in traveling, and keeping travelers satisfied. Thus, studying and reducing travel time in ITS is beneficial in different applications.The classic density-based Lighthill Whitman Richards (LWR) equation for modeling traffic flow is the starting point in this dissertation. A more recent travel time dynamics function built on top of …


Controlled Manipulation Of Droplets On Fibers: Fundamentals And Printing Applications, Yueming Sun Aug 2022

Controlled Manipulation Of Droplets On Fibers: Fundamentals And Printing Applications, Yueming Sun

All Dissertations

In this dissertation, the drop interactions with a single fiber is discussed under an application angle for the development on new Drop-on-Demand (DOD) printhead using a fiber-in-a-tube platform[1] to print highly viscous materials[2]. To control the drop formation and manipulation on fiber, one needs to know how the fiber wetting properties and the fiber diameter influence drop formation. And then, one needs to know the effects of fiber movement in the device on drop formation. These two questions constitute the main theme of this dissertation.

Before this study, it was accepted that the liquids could not form axisymmetric droplets if …


Smart Motor Syringe System, Connor Wilson Mar 2022

Smart Motor Syringe System, Connor Wilson

Electrical Engineering

In this document a proof-of-concept design is developed and implementation to showcase the latest development in an ongoing effort to produce a series of automated syringe pumps.


Comparative Analysis Of Winglet Efficiency On Supercritical Versus Traditionally Cambered Airfoils, Evan Cathers Jan 2022

Comparative Analysis Of Winglet Efficiency On Supercritical Versus Traditionally Cambered Airfoils, Evan Cathers

Electronic Theses and Dissertations

This study serves to define the performance of several industry-recognized and exploratory wing tip devices on aircraft wings utilizing contemporary supercritical airfoil geometry. For comparison, the same examination is performed on a wing comprised of traditionally cambered airfoils, the platform upon which winglets were initially developed. The supercritical wing design is based on that of the Airbus A320, while the conventional airfoil is based upon the Boeing 737-800 platform. Tip devices selected for analysis include blended, raked, split scimitar, fence, and spiroid winglets, as well as tip sails, characterized by the spreading of a bird’s primary flight feathers. Methodology for …


Development Of A Method To Model An Enclosed, Coaxial Carbon Nanotube Speaker With Experimental Validation, Suraj Prabhu Jan 2021

Development Of A Method To Model An Enclosed, Coaxial Carbon Nanotube Speaker With Experimental Validation, Suraj Prabhu

Dissertations, Master's Theses and Master's Reports

Carbon nanotube (CNT) speakers operate on heat as compared to conventional loudspeakers that operate on vibration. CNT speakers are extremely lightweight, stretchable, flexible, and have high operating temperatures. Due to these advantages, CNT speakers are being considered as a viable replacement option for conventional loudspeakers. One such application is automotive exhaust noise control. The goal of this research is to design an enclosed, coaxial CNT speaker and to develop a modeling method to model this speaker using COMSOL Multiphysics.

As part of this research, an enclosed, coaxial CNT speaker was designed and manufactured for automotive exhaust noise control. The first …


Characterization Of Photoacoustic Flow Cytometry Signals, Craig Benzinger May 2020

Characterization Of Photoacoustic Flow Cytometry Signals, Craig Benzinger

Electronic Theses and Dissertations

Photoacoustic flow cytometry has been utilized to clinically determine the presence of melanoma circulating tumor cells (CTCs). Further investigation was conducted into the morphology of detection signals and how they could be manipulated to allow for further classification. Novel features were extracted from waveforms that appear to have strong classification ability. Neural networks were also used to determine classification potential and the creation of feature mapping for future unsupervised classification. Detections were expanded from single waves to a time dependent multiwave event. Waveforms were also determined to be of non-parametric distribution, allowing for classification by neural network but not allowing …


Effects Of Design Autonomy On The Flow Experience, Antonio F Coriano May 2020

Effects Of Design Autonomy On The Flow Experience, Antonio F Coriano

Electronic Theses and Dissertations

Most modern workplace settings are laden with operating procedures aimed at standardizing action in the name of efficiency. The cost of this standardization is the autonomy of the operator. Mihaly Csikszentmihalyi stated the problem concisely in his 1975 work Beyond Boredom and Anxiety “… [M]ost of the institutions that take up our time…are organized around the assumption that serious work is grim and unpleasant. Because of this assumption, most of our time is spent doing unpleasant things”. An experiment was created to study and better understand how to redress this harmful situation. Sixteen subjects were given a SolidWorks computer-aided design …


Vector Flow Imaging In Pediatric Cardiology - Extracting And Validating Data, Mason Belue May 2019

Vector Flow Imaging In Pediatric Cardiology - Extracting And Validating Data, Mason Belue

Biomedical Engineering Undergraduate Honors Theses

In the field of bedside cardiac diagnostic imaging, Doppler Ultrasound (DU) is the gold standard for diagnosing heart conditions. The largest benefit of DU is its ability to noninvasively image cardiac flow and allow the estimation of blood velocity and quantification of anatomical disease. However, to get correct velocity estimation, the position of the transducer in relation to the flow field needs to be known. This is the problem of angle/direction dependency and limits DUs accuracy when imaging in areas where perfect alignment or exact position of the transducer in relation to flow field is not possible or known, such …


Streamwise Flow-Induced Oscillations Of Bluff Bodies - The Influence Of Symmetry Breaking, Tyler Gurian Jul 2018

Streamwise Flow-Induced Oscillations Of Bluff Bodies - The Influence Of Symmetry Breaking, Tyler Gurian

Masters Theses

The influence of symmetry breaking on the flow induced oscillations of bluff bodies in the steamwise direction is studied. First, a series of experiments is conducted on a one-degree-of-freedom circular cylinder allowed to exhibit pure translational motion in the streamwise direction over a range of reduced velocities, 1.4 < U* < 4.4, corresponding to a Reynolds number range of 970 < Re < 3370. Two distinct regions of displacements were observed in reduced velocity ranges of 1.6 < U* < 2.5 and 2.75 < U* < 3.85. Measured force coefficients in the drag and lift direction were examined, along with the wake visualization, through the range of reduced velocities, to infer the resulting wake modes. A new Alternating Symmetric (AS) mode was found. This transition from symmetric to AS shedding occurred near the end of the first region of response. Similar tests were run with a square prism in the parameter space of 2.4 < U* < 5.8 and 757 < Re < 1900 over angles of incidence of 0° ≤ α ≤ 45°. A distinct region of lock-in is observed for α = 0°, 2.5°, 5°, 7.5° over 3.2 < U* < 5.4 for α = 0°, and decreasing with increasing α. The wake structures were found to be roughly symmetric for α = 0°, but transitioned towards asymmetry …


The Interaction Of Ignition And In-Cylinder Flow On Flame Kernel Development And Its Impacts On Combustion In An Optically Accessible Direct Injection Engine, Yanyu Wang Jan 2018

The Interaction Of Ignition And In-Cylinder Flow On Flame Kernel Development And Its Impacts On Combustion In An Optically Accessible Direct Injection Engine, Yanyu Wang

Dissertations, Master's Theses and Master's Reports

A significant challenge facing spark-ignited (SI) engines to achieve higher efficiency via highly diluted combustion is the quickly increased combustion instability as the dilution level increases. The flow motion variation has been identified as a dominant factor that introduces combustion variability at highly diluted conditions. However, the detailed mechanism of how the variation in flow motion impacts the flame kernel development and introduces combustion instability is only partially understood. This research investigated the impacts of the in-cylinder flow on variability of the ignition and early flame kernel development in a single cylinder direct-injection spark-ignition (DI-SI) optically accessible engine and accessory …


Joe On The Go, Nico Ledwith, Grayson Meurrens Jun 2017

Joe On The Go, Nico Ledwith, Grayson Meurrens

Computer Engineering

The ultimate goal for this project is to design an automatic, large capacity coffee maker. The system should be able to detect when a cup or mug is in position to receive coffee, then dispense a cup’s worth (~ 8oz) of coffee. When the coffee in the urn is getting low, our system should be able to allow a person to put new coffee grounds in the top, then push a button to start the coffee brewing process. More specifically, we had to accomplish the following tasks in order to meet our goals: solving the issue of transporting water from …


The Development Of A Partial Flow Sensor For Tiles, Richard Mcever May 2017

The Development Of A Partial Flow Sensor For Tiles, Richard Mcever

Chancellor’s Honors Program Projects

No abstract provided.


Piv Analysis Of Wake Structure Of Real Elephant Seal Whiskers, Joseph Antun Bunjevac Jan 2017

Piv Analysis Of Wake Structure Of Real Elephant Seal Whiskers, Joseph Antun Bunjevac

ETD Archive

Seals are able to accurately detect minute disturbances in the ambient flow
environment using their whiskers, which is attributed to the exceptional capability of
their whiskers to suppress vortex-induced vibrations in the wake. To explore potential applications for designing smart flow devices, such as high-sensitivity underwater
flow sensors and drag reduction components, researchers have studied how the role
of some key parameters of whisker-like morphology affect the wake structure. Due to
the naturally presented variation in size and curvature along the length of whiskers,
it is not well understood how a real whisker changes the surrounding flow and the
vortex …


Sensitivity Analysis Of Geometry Changes In The Simulation Of Basilar Aneurysms, Paul Eserkaln Dec 2016

Sensitivity Analysis Of Geometry Changes In The Simulation Of Basilar Aneurysms, Paul Eserkaln

Theses and Dissertations

Computer simulation is a useful tool in the research and treatment of basilar aneurysms. Current technology allows researchers to create 3D models from cerebral vasculature in-vivo, allowing for the investigation of surgical options with minimal risk to the patient. The method used to construct these models overlooks smaller lateral arterial branches which are difficult to discern due to resolution limits of the imaging process. These lateral branches have minimal impact on the overall blood flow through the basilar artery, but they play a significant role in the health of the patient, so it is important to ensure sufficient blood will …


Ncma Groundwater Model Using Usgs Modflow-2005/Pest, Brian Matthew Wallace Jun 2016

Ncma Groundwater Model Using Usgs Modflow-2005/Pest, Brian Matthew Wallace

Master's Theses

A numerical model for the NCMA aquifer complex is presented. The objective of the study is to develop a numerical groundwater model for the NCMA aquifer system to enhance the understanding of subsurface groundwater flow. Infiltration, streamflow, pumping, and return flows are implemented to characterize the aquifer complex over time. The numerical model is calibrated to municipal and monitoring well data, average monthly water balances, and hydraulic contours. Transient aquifer inflows and outflows are assessed in the results of the study and are compared to balance terms from previous studies. The 2007 Todd Engineers Study subsurface inflows and outflows generate …


The Effects Of Upstream Straight Pipe Length On Magnetic Flow Meter Accuracy, Bradley C. Clawson May 2016

The Effects Of Upstream Straight Pipe Length On Magnetic Flow Meter Accuracy, Bradley C. Clawson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In closed conduit water systems, being able to accurately measure flow is absolutely essential. For many meter designs, including electromagnetic induction meters (also known as magnetic flow meters), the greatest accuracy is achieved when the device is calibrated correctly. Optimal meter accuracy often depends on the flow conditions associated with the upstream geometry in the pipe system. Manufacturers typically give standards for the length of straight pipe required upstream of the meter. These standards vary, however, and do not address every possible configuration that may be installed upstream of the straight pipe requirement.

An investigation on the effects of the …


Experimental Study Of The Flow Of Ferrofluid In A Porous Media Under A Magnetic Field, Muskaan Khurana Jan 2016

Experimental Study Of The Flow Of Ferrofluid In A Porous Media Under A Magnetic Field, Muskaan Khurana

Dissertations, Master's Theses and Master's Reports

This research presents results from a laboratory-scale experimental setup that was designed to visualize the behavior of ferrofluid percolation through a porous media. Ferrofluids are colloidal suspensions made of magnetic particles of a few nanometers and stabilized in carrier liquids like water or mineral oil. Ferrofluids get magnetized and align themselves in the direction of a magnetic field when a field gradient is applied.

With the help of this experiment we investigate the viability of controlling fluid flow in porous medium by a magnetic field in vicinity. The experiments show that ferrofluids can be used as a transporting media to …


Electrokinetic Flow In A Nanochannel With An Overlapped Electrical Double Layer, Zhuorui Song May 2015

Electrokinetic Flow In A Nanochannel With An Overlapped Electrical Double Layer, Zhuorui Song

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research is a theoretical study aiming to improve the understanding of nanofluidic flows. Nanofluidic flows have a wide range of potential application in many fields, such as DNA analysis, drug delivery, analyte separation, power generation, and so on. The most common material used in nanofluidic flows is silica whose surfaces are charged mainly due to proton exchange with the fluids. Charges on the surfaces as well as near the surfaces in the fluid side cause a significantly different response of the fluids to the applied electric field or pressure difference compared to those at normal scale. In the previous …


Investigating Instabilities With Hec-Ras Unsteady Flow Modeling For Regulated Rivers At Low Flow Stages, Jennifer Kay Sharkey Dec 2014

Investigating Instabilities With Hec-Ras Unsteady Flow Modeling For Regulated Rivers At Low Flow Stages, Jennifer Kay Sharkey

Masters Theses

Dams are used throughout the United States for generation of electricity and flood control. The Tennessee River Valley’s regulated river system extends through Tennessee and parts of Kentucky, Mississippi, Alabama, Georgia, North Carolina, South Carolina, and Virginia. Of the dams in this area, 49 are managed by the Tennessee Valley Authority (TVA). The TVA forecasts and monitors the activities related to these dams and others in the area on an around-the-clock basis to ensure maximum generation potential is attained and to prevent flooding of the surrounding cities. To best forecast hydrology for the regulated river system, the TVA chose to …


Surface Acoustic Wave (Saw)-Based Gas Flow Sensor, Nisar Ahmad Oct 2014

Surface Acoustic Wave (Saw)-Based Gas Flow Sensor, Nisar Ahmad

Dissertations (1934 -)

There has been a growing interest in using SAW devices for sensing various physical parameters such as pressure, acceleration, temperature, and gas. The current research has been undertaken to derive a model of a SAW-based gas flow rate sensor, using the principle of heat transfer with the flow of gas. It consists of a SAW delay line fabricated on a suitable substrate and a thin film heater to heat the SAW device to a suitable temperature above the ambient. The delay line is connected in the feedback loop of an rf-amplifier resulting in a delay line stabilized SAW oscillator. When …


Weir-Baffled Culvert Hydrodynamics Evaluation For Fish Passage Using Particle Image Velocimetry And Computational Fluid Dynamic Techniques, Mohanad A. Khodier May 2014

Weir-Baffled Culvert Hydrodynamics Evaluation For Fish Passage Using Particle Image Velocimetry And Computational Fluid Dynamic Techniques, Mohanad A. Khodier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to a recent increase in environmental awareness regarding fish passage through hydraulic structures, including culverts, an evaluation of passage of wild brown trout through a weir-baffled, prototype-scale culvert, was conducted under a variety of culvert slopes and discharge conditions. The influence of the fish sample population and the lengths of the individual fish on passage rates were investigated. The data showed that the fish sample size of 25 per test was sufficiently large to minimize sample size dependency. Fish behavior, including resting/staging zone locations, while traversing the culvert was observed and reported. Two preferable resting zones for the fish …


Development And Validation Of A Computational Model For Studying Secondary Droplet Breakup In Time-Varying Flows, Brandan A. West Jun 2013

Development And Validation Of A Computational Model For Studying Secondary Droplet Breakup In Time-Varying Flows, Brandan A. West

Honors Theses

Secondary droplet breakup is an important topic in fluid mechanics that has applications in many atomization processes. To date, the experimental and computational research of secondary droplet breakup has focused primarily on the breakup process in flows that have steady velocities. This study utilizes computational fluid dynamics software called Star-CCM+ Version 7.04.006 to study the effects of time-varying flows on the droplet breakup process. Time-varying flows are more representative than steady flows are of the flow situations in combustion chambers of high-level engines such as jet and rocket engines. Weber number is the ratio of the external flow’s inertial forces …


Economic Report On Vanadium Redox Flow Battery With Optimization Of Flow Rate, Kevin Spellman, Kendrick Stiles, Ian Little May 2013

Economic Report On Vanadium Redox Flow Battery With Optimization Of Flow Rate, Kevin Spellman, Kendrick Stiles, Ian Little

Chancellor’s Honors Program Projects

No abstract provided.


Secondary Droplet Breakup In Periodic Aerodynamic Flows Using Computational Fluid Dynamics, Krystle Gallo Jun 2012

Secondary Droplet Breakup In Periodic Aerodynamic Flows Using Computational Fluid Dynamics, Krystle Gallo

Honors Theses

Combustion instability is characterized by periodic fluctuations during the combustion process. Such instabilities can cause a reduction in engine performance and damage to engine components. In liquid fueled combustion, some types of combustion instability may be driven by changes in fuel droplet size distribution. The fuel droplet size distribution can be changed if the original or “primary” fuel droplets are broken apart by the flow. This is called secondary droplet breakup. The smaller drops that are created during breakup are consumed more rapidly and increase the energy release rate, which may act as a sustaining force of the instability. Currently, …


Life-Cycle Optimization And Flow Control In A Nickel-Zinc Flow Assisted Battery, Steve Lever Jan 2012

Life-Cycle Optimization And Flow Control In A Nickel-Zinc Flow Assisted Battery, Steve Lever

Dissertations and Theses

Nickel-Zinc flow-assisted rechargeable batteries are currently being explored as a potential new generation of large-scale, low-cost energy storage devices. The viability of a commercial nickel-zinc battery has been hindered by the well-known phenomena of dendrite formation and zinc morphology variation over time. Applying electrolyte flow to traditional nickel-zinc battery systems has demonstrated significant life cycle performance improvements by reducing both dendrite formation and morphological variation. It has also been demonstrated that periodic low-current reconditioning discharge further improves cycle life. This thesis examines the effect of eliminating electrolyte flow during discharge of nickel-zinc flow assisted batteries, which would allow a much …


Experimental Characterization Of Baffle Plate Influence On Turbulent And Cavitation Induced Vibrations In Pipe Flow, Gavin J. Holt Jun 2011

Experimental Characterization Of Baffle Plate Influence On Turbulent And Cavitation Induced Vibrations In Pipe Flow, Gavin J. Holt

Theses and Dissertations

Turbulent and cavitation induced pipe vibration is a large problem in industry often resulting in pipe failures. This thesis provides an experimental investigation on turbulent flow and cavitation induced pipe vibration caused by sharp edged baffle plates. Due to large pressure losses across a baffle plate, cavitation can result. Cavitation can be destructive to pipe flow in the form of induced pipe wall vibration and cavitation inception. Incipient and critical cavitation numbers are design points that are often used in designing baffle plate type geometries. This investigation presents how these design limits vary with the influencing parameters by exploring a …


Micro-Piv Of Self-Propelling Bi-Slugs In A Micro Channel, Lilla M. Safford Smith Jun 2011

Micro-Piv Of Self-Propelling Bi-Slugs In A Micro Channel, Lilla M. Safford Smith

Honors Theses

Bi-slugs are fluid entities involving two dissimilar fluids that move “on their own” due to differences in surface tension. At the micro-fluidic scale this sort of motion may be useful to efficiently transport small quantities of fluid from place to place. This study uses Micro-Particle Image Velocimetry (µ-PIV) techniques to investigate self propelling bi-slug flows. The bi-slugs examined are made of ethylene glycol and Xiameter PMX-200 Silicone Fluid (5cst and 10cst) and placed in a glass micro-channel of approximately 1mm diameter. The Reynolds number (Re) range considered (based on ethylene glycol in the slug) is 2.54 - 1.07 and the …


Design Of Equipment For The Study Of Non-Isothermal Flow In Polymer Fluid, Opeoluwa Oluwaseun Kolawole May 2011

Design Of Equipment For The Study Of Non-Isothermal Flow In Polymer Fluid, Opeoluwa Oluwaseun Kolawole

Masters Theses

The polymer industry is an ever growing industry, and, as it grows, companies are continuously looking for ways to study and understand the behaviors of polymers in relation to the processing and production. This is to ensure the production of high quality products and to improve existing products.
An important parameter during polymer processing is temperature. Temperature control affects several rheological parameters such as viscosity, and in turn the quality of the final products. Frictional or viscous heating is a very important part of polymer processing and occurs in almost every polymer processing operation.
The objective of this research is …


Analysis And Comparison Of Effects Of An Airfoil Or A Rod On Supersonic Cavity Flow., William Leland Fowler Dec 2010

Analysis And Comparison Of Effects Of An Airfoil Or A Rod On Supersonic Cavity Flow., William Leland Fowler

Masters Theses

The effects of an airfoil at different angles of attack and a circular cylindrical rod within the edge of the boundary layer flow at the leading edge of a cavity as a device for controlling the large pressure fluctuations (resonance tones) in the cavity were investigated. The airfoil results were compared with the rod in crossflow method positioned at the same leading edge location. The cavity used for testing corresponded to a length to depth ratio, L/D of 11.0/2.25 with a length to width ratio, L/W of 11.0/3.00 at a freestream Mach 1.84 flow. The study included measurements of dynamic …