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Full-Text Articles in Engineering

Direct Synthesis Of Graphene On Niobium And Niobium Nitride, Robin Ekeya, Otto Zietz May 2018

Direct Synthesis Of Graphene On Niobium And Niobium Nitride, Robin Ekeya, Otto Zietz

Undergraduate Research & Mentoring Program

Since its isolation by mechanical exfoliation in 2004, graphene has attracted enormous interest from the scientific community not the least because of its unique physical and electronic properties. Among these, graphene’s ballistic electron transport and proximity induced superconductivity make graphene-superconductor (GS) hybrid structures a scientifically promising area.


Three Speed 3d Printed Magnetic Gear, Robert J. Rutherford May 2018

Three Speed 3d Printed Magnetic Gear, Robert J. Rutherford

Undergraduate Research & Mentoring Program

Power transmission is traditionally achieved with a mechanical gear. Mechanical gears require maintenance, cause vibration, and have no overload protection. Magnetic gears offer an innovative solution to these drawbacks as they do not require regular maintenance, have no need for lubrication, create very little acoustic noise, have built in overload protection and as a result of these advantages, have a longer lifetime of operation. This research focused upon the design, assembly and demonstration of the magnetic gear concept. The research used a solid works design, 3D printed ABS plastic housing, and use of neodymium magnets and ferromagnetic iron segments.

This …


Real-Time Object Detection And Tracking On Drones, Tu Le May 2018

Real-Time Object Detection And Tracking On Drones, Tu Le

Undergraduate Research & Mentoring Program

Unmanned aerial vehicles, also known as drones, have been more and more widely used in recent decades because of their mobility. They appear in many applications such as farming, search and rescue, entertainment, military, and so on. Such high demands for drones lead to the need of developments in drone technologies. Next generations of commercial and military drones are expected to be aware of surrounding objects while flying autonomously in different terrains and conditions. One of the biggest challenges to drone automation is the ability to detect and track objects of interest in real-time. While there are many robust machine …


Flux Focusing Axial Magnetic Gear, Robert J. Rutherford May 2017

Flux Focusing Axial Magnetic Gear, Robert J. Rutherford

Undergraduate Research & Mentoring Program

Power transmission is traditionally achieved with a mechanical gear. These gears require maintenance, cause vibration, and have no overload protection. Magnetic gears (MGs) offer an innovative solution to these drawbacks as they do not require regular maintenance, have no need for lubrication, create very little acoustic noise, have built in overload protection and as a result of these advantages, have a longer lifetime of operation. The flux focusing axial magnetic gear (FFAMG) was assembled for future testing of power transmission, conversion, and generation applications.

Gears are used to transmit power by converting low speed-high torque rotary motion into high speed-low …


Deposition Velocity Dependence On Urban Morphology, Rawand Muzafar Rasheed May 2017

Deposition Velocity Dependence On Urban Morphology, Rawand Muzafar Rasheed

Undergraduate Research & Mentoring Program

Understanding the interactions between the atmospheric boundary layer and urban structures provides insights into emerging problems such as green building design as well as dispersion and deposition of pollutants on urban structures. Characterization of deposition velocity dependence through the naphthalene sublimation method on model urban structures is conducted herein where the analogous fundamental transport mechanisms of momentum and mass transport is obtained via mass of naphthalene transferred. Via wind tunnel experiments, results show that deposition velocity of naphthalene from urban structures increases with increased number of urban structures ahead of the point of investigation. This is attributed to the wakes …


Jet Bounce In Low Gravity, Caleb Turner May 2017

Jet Bounce In Low Gravity, Caleb Turner

Undergraduate Research & Mentoring Program

Liquid jets rebound (‘bounce’) from superhydrophobic surfaces when they impinge at oblique angles. We call this interesting phenomena ‘jet bounce’ and in this work we investigate the phenomena at large length scales in a reduced gravitational environment. For example, for water at Reynolds numbers 0 < Re < 3500 and surface normal Weber numbers 0 < We < 60 we characterize the response of the jets on the hydrophobic surface in the brief 2.1s micro-gravity environment achieved using a drop tower. It is observed that by varying jet velocity, flow rate, jet diameter, and incident angle we observe up to four distinct regimes of behavior. The various regimes may be targeted for specific applications and we demonstrate a variety of unique jet bounce behaviors for applications such as no-touch, no-contact fluid-thermal transport for spacecraft unit operations such as contaminated water processing, device cooling, and cryogenic fluids transport and management.

Stable jet bounce from small diameter jet ≈ 1 mm and low impact angle. Characterizing Reynolds number ≈ 900 and normal Weber number ≤ 10 allow jet bounce to rebound in non-destructive behavior.


Conditional Averaging And Classification In The Near Wake Of A Wind Turbine Array Boundary Layer, Sarah E. Smith May 2017

Conditional Averaging And Classification In The Near Wake Of A Wind Turbine Array Boundary Layer, Sarah E. Smith

Undergraduate Research & Mentoring Program

Flow perturbation induced by interaction with a turbine rotor produces considerable turbulence which can alter the productivity of subsequent units within a wind farm. Previous methods have characterized near wake vorticity of a single turbine as well as recovery distance for various turbine array configurations. This study aims to build from previous methods of analysis from the perspective of the rotor well within a turbine array and develop a model to examine points of significant imposition in relation to rotational effects. Hot wire anemometry was employed downstream of a turbine located in the middle of the third row in a …


The Effect Of Plasma On Graphene Quality In An Inductively Couple Plasma Chemical Vapor Deposition Reactor, Brendan Coyne May 2017

The Effect Of Plasma On Graphene Quality In An Inductively Couple Plasma Chemical Vapor Deposition Reactor, Brendan Coyne

Undergraduate Research & Mentoring Program

Despite continued interest in research and application development, full scale graphene production is still limited by many factors including prohibitively high growth temperature requirements. Extremely high quality graphene growth is possible at high temperatures using chemical vapor deposition (CVD). Use of an inductively coupled plasma chemical vapor deposition (ICP CVD) reactor with the benefit of precursor gas decomposition through plasma generation, may provide possibility to reduce growth temperature. Herein, we report plasma’s effects on graphene growth by comparing growths of increasing power supplied to plasma generation and changes in precursor gas ratios. Plasma composition was characterized by ultraviolet and visible …


Complex Capillary Fluidic Phenomena For Passive Control Of Liquids In Low-Gravity Environments, Logan Torres Jan 2016

Complex Capillary Fluidic Phenomena For Passive Control Of Liquids In Low-Gravity Environments, Logan Torres

Undergraduate Research & Mentoring Program

In an effort to further apply the recent results of puddle jumping research, we seek to expand the oblique droplet impact studies of others by exploiting large liquid droplets in the near weightless environment of a drop tower. By using the spontaneous puddle jump mechanism, droplets of volumes 1 mL ≤ V ≤ 3 mL with corresponding Weber numbers of We ≈ 1 are impinged on surfaces inclined in the range 40° ≤ α ≤ 80° (measured from the horizontal plane). Impact surface wetting characteristics exhibit static contact angles θstatic = 165 ± 5°. All impacts result in complete rebound. …


Quantum Yield Optimization For Semiconductor Photocatalysis Systems, Ryan Catabay Jan 2016

Quantum Yield Optimization For Semiconductor Photocatalysis Systems, Ryan Catabay

Undergraduate Research & Mentoring Program

The utilization of photocatalysis has a well-known potential for mineralizing organic contaminants in water purification processes. A continuous flow photocatalytic reactor was developed in order to test the quantum yield of titanium dioxide, a semiconductor material well known for its photocatalytic properties. In order to build this reactor, multiple manufacturing methods were performed: manual and CNC machining, laser cutting, waterjet cutting, and chemical synthesis. A continuous flow reactor was particularly designed for a controlled, variable radiant flux of ultraviolet light. This continuous UV radiation excites the photocatalyst, generating electron hole pairs that form hydroxyl radicals, which in turn mineralize organic …


Design For Fractal Grid Generated Turbulence, Moira Gion Jan 2016

Design For Fractal Grid Generated Turbulence, Moira Gion

Undergraduate Research & Mentoring Program

Fractal geometry can be used to find organization or order in something that appears to be in disorder, or chaos. Turbulence is viewed as one place where fractal geometry can be found in nature. The irregularity in fluid flow is dependent on the initial conditions. In the past, the idea of self-similarity has been used to develop statistical theories of energy cascade in a turbulent flow. Recent studies have done experiments on obstructing flows with fractal objects to observe intermittency, (or self-similarity) within a turbulent flow. Experiments on fractal grid generated turbulence has been performed by other research groups, so …


Engineered Mushing Cooker, Aimee Ritter Jan 2016

Engineered Mushing Cooker, Aimee Ritter

Undergraduate Research & Mentoring Program

This project revolves around building methanol cookers for dog mushers in the Iditarod and for the Denali Park Ranger Kennel in Denali National Park, Alaska. Traditional cookers are bulky, slow to burn, and use up a lot of fuel. Our goal has been to revolutionize the way mushing cookers look and perform. Our cookers are built to pack well in the sleds, heat up to 3 gallons of snowmelt, perform in arctic climates, use methanol (specifically HEET) for fuel, and be lightweight. A traditional cooker would use 3 to 4 bottles or more of HEET (36-48+oz.) and take at least …