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Full-Text Articles in Mechanical Engineering

An Integrated Resource Plan For Arizona Public Service Electric (Aps), Irene Boghdadi, Randy Chiu May 2020

An Integrated Resource Plan For Arizona Public Service Electric (Aps), Irene Boghdadi, Randy Chiu

Master's Projects and Capstones

Our Masters Capstone Project is an Integrated Resource Plan (IRP) for Arizona’s largest electric utility, Arizona Public Service Electric (APS).

An IRP is developed by utilities to identify the optimal combination of demand- and supply-side resources needed to reliably meet forecasted demand for energy and capacity, including a planning reserve margin, over a future period.

In addition to APS’s obligation to serve the growing load in Arizona while minimizing costs, it is required by the state to adhere to the Renewable Energy Standard (RES) policy of 15 percent retail sales from renewable energy resources by 2025.

The analysis described in …


Application Of Optimal Switching Using Adaptive Dynamic Programming In Power Electronics, Ataollah Gogani Khiabani May 2020

Application Of Optimal Switching Using Adaptive Dynamic Programming In Power Electronics, Ataollah Gogani Khiabani

Mechanical Engineering Research Theses and Dissertations

In this dissertation, optimal switching in switched systems using adaptive dynamic programming (ADP) is presented. Two applications in power electronics, namely single-phase inverter control and permanent magnet synchronous motor (PMSM) control are studied using ADP. In both applications, the objective of the control problem is to design an optimal switching controller, which is also relatively robust to parameter uncertainties and disturbances in the system. An inverter is used to convert the direct current (DC) voltage to an alternating current (AC) voltage. The control scheme of the single-phase inverter uses a single function approximator, called critic, to evaluate the optimal cost …


Control And Locomotion Of Inertially And Magnetically Actuated Multi-Scale Robotic Systems, Ehab Al Khatib May 2020

Control And Locomotion Of Inertially And Magnetically Actuated Multi-Scale Robotic Systems, Ehab Al Khatib

Mechanical Engineering Research Theses and Dissertations

In this research, two actuation systems were introduced, inertial and magnetic actuation. In the inertial actuation, the robot used the transfer of momentum to navigate, and this momentum could be generated by spinning masses and wheels. Recent studies in our System Laboratory proved that a wide range of inertially actuated locomotion systems could be generated. This can be achieved by using a family tree approach, starting from a very simple system, and progressively evolving it to more complex ones. The motion diversity of these robots inspired us to extend their locomotion from a macro scale to millimeter and micro scales. …


Polarity Effects Of Aluminium Nitride Thin Films And Morphological Characterization Of Molybdenum Thin Films, Aseem Poudyal May 2020

Polarity Effects Of Aluminium Nitride Thin Films And Morphological Characterization Of Molybdenum Thin Films, Aseem Poudyal

Mechanical Engineering ETDs

AlN (Aluminium Nitride) is a piezoelectric material that is often used in numerous applications as a transducer. C-axis crystal orientation control of AlN is very important as it corresponds to a high piezoelectric coefficient. Crystal orientation of sputtered AlN is strongly affected by its deposition parameters such as sputtering pressure, target to substrate distance, growth temperature, gas pressure and frequency/duty cycle in the case of pulsed DC sputtering. Crystal orientation of AlN depends on the energy of the sputtered atom and the mobility of the adatoms on the surface of the substrate. Varying the deposition parameters can alter the kinetic …


Hollow-Core Photonic Crystal Fiber Mach–Zehnder Interferometer For Gas Sensing, Kaveh Nazeri, Farid Ahmed, Vahid Ahsani, Hang-Eun Joe, Colin Bradley, Ehsan Toyserkani, Martin B. G. Jun May 2020

Hollow-Core Photonic Crystal Fiber Mach–Zehnder Interferometer For Gas Sensing, Kaveh Nazeri, Farid Ahmed, Vahid Ahsani, Hang-Eun Joe, Colin Bradley, Ehsan Toyserkani, Martin B. G. Jun

Manufacturing & Industrial Engineering Faculty Publications

A novel and compact interferometric refractive index (RI) point sensor is developed using hollow-core photonic crystal fiber (HC-PCF) and experimentally demonstrated for high sensitivity detection and measurement of pure gases. To construct the device, the sensing element fiber (HC-PCF) was placed between two single-mode fibers with airgaps at each side. Great measurement repeatability was shown in the cyclic test for the detection of various gases. The RI sensitivity of 4629 nm/RIU was demonstrated in the RI range of 1.0000347–1.000436 for the sensor with an HC-PCF length of 3.3 mm. The sensitivity of the proposed Mach–Zehnder interferometer (MZI) sensor increases when …


Exploring Attacks And Defenses In Additive Manufacturing Processes: Implications In Cyber-Physical Security, Nicholas Deily May 2020

Exploring Attacks And Defenses In Additive Manufacturing Processes: Implications In Cyber-Physical Security, Nicholas Deily

McKelvey School of Engineering Graduate Student Theses & Dissertations

Many industries are rapidly adopting additive manufacturing (AM) because of the added versatility this technology offers over traditional manufacturing techniques. But with AM, there comes a unique set of security challenges that must be addressed. In particular, the issue of part verification is critically important given the growing reliance of safety-critical systems on 3D printed parts. In this thesis, the current state of part verification technologies will be examined in the con- text of AM-specific geometric-modification attacks, and an automated tool for 3D printed part verification will be presented. This work will cover: 1) the impacts of malicious attacks on …


Mechanical Analysis And Modeling Of Porous Thermal Barrier Coatings, Shiyu Cui, Wenping Liang, Luis Saucedo Mora, Qiang Miao, Joseph P. Domblesky, Hao Lin, Lijia Yu May 2020

Mechanical Analysis And Modeling Of Porous Thermal Barrier Coatings, Shiyu Cui, Wenping Liang, Luis Saucedo Mora, Qiang Miao, Joseph P. Domblesky, Hao Lin, Lijia Yu

Mechanical Engineering Faculty Research and Publications

Thermal barrier coatings (TBCs) are applied to the surface of components that are used in gas turbines and aircraft engines in order to increase the heat load. In this study, the cross-sectional microstructures of TBCs were investigated via scanning electron microscopy. After calculating the porosity and the pore size distribution, a two-dimensional finite element model with four different porosities (0, 1, 3, and 5%) were established. A stochastic method was used to generate a randomly distributed porous structure. Based on the results of FE analysis and nanoindentation tests, It was found that, at a high porosity (>3%), radial cracks …


Blood Flow Simulation Of Particle Trapping In Models Of Arterial Bifurcations, Qihang Xu May 2020

Blood Flow Simulation Of Particle Trapping In Models Of Arterial Bifurcations, Qihang Xu

McKelvey School of Engineering Graduate Student Theses & Dissertations

This thesis describes the particle trapping mechanism in blood flow in different arterial bifurcation models. For validation of CFD calculations, a T-junction model and a Y-junction model are analyzed. In both the models, there is one inlet pipe with two outlet pipes creating a symmetric bifurcation at some angle from the centerline of the inlet pipe. Naiver-Stokes (RANS) equations are solved for single phase laminar flow using the commercial CFD software ANSYS Fluent. After validation, Eulerian simulations are performed by using the Discrete Phase Model (DPM) for two-phase flow with particles injected in different bifurcation models with bifurcation angle of …


Development And Application Of Elliptic Blending Lag K-Omega Sst Standard And Wall-Distance-Free Turbulence Model, Wenjie Shang May 2020

Development And Application Of Elliptic Blending Lag K-Omega Sst Standard And Wall-Distance-Free Turbulence Model, Wenjie Shang

McKelvey School of Engineering Graduate Student Theses & Dissertations

In recent decades, Computational Fluid Dynamics (CFD) has become the most widely used technology to understand the fundamental complex fluid dynamics of turbulent flows as well as for modeling of turbulent flows in industrial applications. In industrial applications, the widely used methodology is to solve Reynolds-Average Navier-Stokes Equations (RANS) equations in conjunction with a turbulence model since it strikes a balance between accuracy and computational cost compared to other high fidelity approaches namely the Large Eddy Simulation (LES) and Direct Numerical Simulation (DNS), There are a large number of turbulence models proposed in past five decades, majority of them are …


Thermal Transport Across The Interface Between Liquid N-Dodecane And Its Own Vapor: A Molecular Dynamics Study, Eric Bird, Jesus Gutierrez Plascencia, Zhi Liang May 2020

Thermal Transport Across The Interface Between Liquid N-Dodecane And Its Own Vapor: A Molecular Dynamics Study, Eric Bird, Jesus Gutierrez Plascencia, Zhi Liang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

There Are Two Possible Thermal Transport Mechanisms at Liquid-Gas Interfaces, Namely, Evaporation/condensation (I.e., Heat Transfer by Liquid-Vapor Phase Change at Liquid Surfaces) and Heat Conduction (I.e., Heat Exchange by Collisions between Gas Molecules and Liquid Surfaces). using Molecular Dynamics (MD) Simulations, We Study Thermal Transport Across the Liquid-Vapor Interface of a Model N-Dodecane (C12H26) under Various Driving Force Conditions. in Each MD Simulation, We Restrict the Thermal Energy to Be Transferred Across the Liquid-Vapor Interface by Only One Mechanism. in Spite of the Complex Intramolecular Interactions in N-Dodecane Molecules, Our Modeling Results Indicate that the Schrage Relationships, Which Were Shown …


Effects Of Hard-To-Soft Segment Ratios On The Synthesis And Physico-Mechanical Properties Of Polyurethane Films, Aaron C. Wilson May 2020

Effects Of Hard-To-Soft Segment Ratios On The Synthesis And Physico-Mechanical Properties Of Polyurethane Films, Aaron C. Wilson

Mechanical Engineering Theses

Blood-contacting cardiovascular stents often induce a secondary clotting event due to unrestricted enzymatic activities. The use of hemocompatible polyurethane coatings on these implantable devices is one of the most promising methods to reduce device rejection. In this study, four commercial polyurethane films of various thicknesses and compositions were evaluated for their anticoagulation properties. Results suggested that these films exhibited excellent thermal and physico-mechanical properties while capable of increasing contact time with blood plasma by over a thousand-fold as compared to a control surface. Due to the unknown structure and composition of these commercial films, polyurethane samples were synthesized from toluene …


Large Scale Grid Integration Of Wind And Solar Power With Storage, Nicholas Moore May 2020

Large Scale Grid Integration Of Wind And Solar Power With Storage, Nicholas Moore

Macalester Journal of Physics and Astronomy

The current energy grid in the United States is dominated by carbon intense energy generation methods that are based on production when and where it is required. However, solar and wind power have proved themselves as the most promising carbon free energy generation sources. Due to the unpredictable and uncontrollable nature of energy production from solar and wind, large scale integration of these resources into the electric grid will require robust storage capacity. In this project, we model the energy grid of the Midcontinent Independent System Operator (MISO) energy region with high concentrations of solar and wind power to analyze …


Investigation Of Particle Interference In Induced Electromagnetic Coil, Elizabeth Soha May 2020

Investigation Of Particle Interference In Induced Electromagnetic Coil, Elizabeth Soha

Honors Scholar Theses

The purpose of this thesis work is to study the effect of a ferromagnetic particle on an induced solenoid’s magnetic field. Solenoids are wound coils that are charged with current to induce a magnetic field. The placement of a particle inside a solenoid interacts with the coil’s magnetic field and therefore changes the coil’s field behavior. This work comprises a parametric study of how particle size and placement within a solenoid affect the solenoid’s magnetic field. A model of the coil and particle is created and parametrically studied using the computational software ANSYS. The results from this simulation help to …


New Policies Give Solar Users An Economic Boost, Olivia Fowler May 2020

New Policies Give Solar Users An Economic Boost, Olivia Fowler

Marriott Student Review

The future looks bright for Solar Energy, as more States and Territories in the United States commit to moving to 100% renewable energy. What are the different states and territories committing to exactly, and what economic incentives are they bringing? Find out in this article by author Olivia Fowley.


A Perceptual Evaluation Of Short-Time Fourier Transform Window Duration And Divergence Cost Function On Audio Source Separation Using Non-Negative Matrix Factorization, Ryan J. Miller May 2020

A Perceptual Evaluation Of Short-Time Fourier Transform Window Duration And Divergence Cost Function On Audio Source Separation Using Non-Negative Matrix Factorization, Ryan J. Miller

Student Theses

Non-negative matrix factorization (NMF) is an established method of performing audio source separation. Previous studies used NMF with supplementary systems to improve performance, but little has been done to investigate perceptual effects of NMF parameters. The present study aimed to evaluate two NMF parameters for speech enhancement: the short-time Fourier transform (STFT) window duration and divergence cost function. Two experiments were conducted: the first investigated the effect of STFT window duration on target speech intelligibility in a sentence keyword identification task. The second experiment had participants rate residual noise levels present in target speech using three different cost functions: the …


Design Of An Orientation Device For Valve Bodies With Blowout Compatibility For Slug Detection, Annie Richardson May 2020

Design Of An Orientation Device For Valve Bodies With Blowout Compatibility For Slug Detection, Annie Richardson

Honors Theses

The Parker Hannifin plant in Batesville, MS, is a manufacturing plant that specializes in A/C and hydraulic tube and hose assemblies that support heavy machinery in the agriculture, logistics and construction industries. Customers place unique orders where the tube size, bending configurations, and adaptors vary widely. Some tubes require valve bodies where the customer can charge the A/C system once it has been assembled. A pierce and press machine is used to pierce the tube and place the valve body in the hole. Many tubes have asymmetric blocks at the end of the tube, with valve bodies placed at customer-requested …


A Study Of The Marketing Analysis Concerning Mind The Gap: A Wall-Bed Space Saving Platform, Brenna Johnson May 2020

A Study Of The Marketing Analysis Concerning Mind The Gap: A Wall-Bed Space Saving Platform, Brenna Johnson

Honors Theses

The purpose of this thesis is to conduct a marketing analysis on the capstone project concerning the product titled Mind the Gap. The thesis will explore the potential industries that could be entered and marketing strategies that would be implemented if the Mind the Gap product was mass produced and either sold online or through brick and mortar locations. Outlined in this research is an analysis of the competitive landscape, potential target markets, situational aspects concerning this product, and the resulting recommended marketing mix. The Mind the Gap is centered around a practical and efficient process which has a goal …


Comparative Analysis And Dynamic Response Of Garolites Under Temperature Spectrum Using Low Velocity Impact Test, Birendra Chaudhary May 2020

Comparative Analysis And Dynamic Response Of Garolites Under Temperature Spectrum Using Low Velocity Impact Test, Birendra Chaudhary

Honors Theses

The purpose of this study was to examine the dynamic response of three different grades of garolites under the temperature spectrum. High-Temperature G-11 Sheet (HTG), Impact Resistance Garolite E-glass (HIG), and Economical Garolite (EG) were tested using an Instron Dynatup 8250 impact tester. Three specimens were used for all three composites and were tested at 6 different temperatures, -10oC, 25oC, 50oC, 100oC, 150oC and 200oC using the Low-Velocity Impact Machine with 20 Kip punch shear load cell. The results showed that HIG had the highest resistance to punch …


Dynamic Characterization Of Duroprotect, A Fiber-Reinforced Ballistics Composite, Ivy A. Turner May 2020

Dynamic Characterization Of Duroprotect, A Fiber-Reinforced Ballistics Composite, Ivy A. Turner

Honors Theses

Dynamic characterization of materials has become increasingly common, as it is important to understand how materials behave under sudden loads. Understanding these properties can aid in material selection for novel designs. DuroProtect, a fiber-reinforced ballistics composite developed by Rӧchling, was tested for its dynamic properties at high strain-rates. The Split Hopkinson Pressure Bar (SHPB) test was used to obtain dynamic properties at high strain-rates under compressive loading conditions. Tests were initially conducted to validate force equilibriums for each sample. The data measured from the strain gages mounted on the incident and transmission bars and the elastic wave propagation theories yields …


Product Realization Capstone: Using Project Management To Optimize Manufacturing Of Charcuterie Boards, Megan Staffieri May 2020

Product Realization Capstone: Using Project Management To Optimize Manufacturing Of Charcuterie Boards, Megan Staffieri

Honors Theses

The purpose of this project was to successfully create 36 charcuterie boards with varying designs during a two-week production period using principles of project management and manufacturing. In the initiation phase, the needs and requirements were assessed according to the project definition. During the planning phase, a work breakdown structure was created, material was researched, a budget was developed, and an initial risk assessment was performed. During the executing phase, the initial designs were prototyped before production began. The controlling phase was done in conjunction with the executing phase. The controlling phase monitored the project management plan and recorded the …


Utilizing The Product Development Process To Bring An Idea From Concept To Production, Sydney Ferguson, Jackson Sneed May 2020

Utilizing The Product Development Process To Bring An Idea From Concept To Production, Sydney Ferguson, Jackson Sneed

Honors Theses

The purpose of this thesis is to document and discuss the five-stage product development process starting with defining a problem and resulting in manufacturing a final product for sale as it was implemented in the Portable Fire Pit Center for Manufacturing Excellence Senior Capstone Project. This project was carried out over the course of the Fall 2019 and Spring 2020 semesters by a team consisting of three Undergraduate Mechanical Engineering majors and two Undergraduate Accountancy majors. The ultimate goal of the project was to carry out a full production run of the Portable Fire Pit outputting fifteen units meeting retail …


College Of Engineering Senior Design Competition Spring 2020, University Of Nevada, Las Vegas May 2020

College Of Engineering Senior Design Competition Spring 2020, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …


Automating 35mm Photographic Film Digitization: X-Y Table Capture System Design And Assessment, Michael J. Bennett May 2020

Automating 35mm Photographic Film Digitization: X-Y Table Capture System Design And Assessment, Michael J. Bennett

Published Works

35mm still image formats are some of the most abundant photographic film types in cultural heritage collections. However, their special handling needs coupled with high resolution digital capture requirements have traditionally posed logistical constraints with regard to the formats’ digitization at scale. Through the use of a programmable X-Y table camera capture system, both slide and strip 35mm photographic film can be digitized in an automated fashion following Federal Agencies Digitization Guidelines (FADGI).


A Study Of The Efficiency And Effectiveness Of The First Four Iterations Of Sierpinski Carpet Fractal-Like Fins At Increasing Angles In Natural Convection, Sophia N. Fleri May 2020

A Study Of The Efficiency And Effectiveness Of The First Four Iterations Of Sierpinski Carpet Fractal-Like Fins At Increasing Angles In Natural Convection, Sophia N. Fleri

Honors College Theses

Fractal geometries have been found in several studies to increase a fin’s thermal performance. Both the reductions of volume and mass accompanied by an increase in performance are desirable to prevent malfunction of the device through passive heat dissipation. The Sierpinski carpet fractal pattern, beginning with a basic square geometry in which an increasing number of perforations are incorporated through each successive iteration, reduces the fin’s mass while increasing its surface area simultaneously; this increase in surface area increases the rate of heat transfer experienced across the fin. The first four iterations of the Sierpinski carpet pattern, each with identical …


The Development Of All Solid-State Optical Cryo-Cooler, Junwei Meng May 2020

The Development Of All Solid-State Optical Cryo-Cooler, Junwei Meng

Optical Science and Engineering ETDs

This dissertation describes the development of an all solid-state optical cryo-cooler. Crystals of 10% wt. ytterbium-doped yttrium lithium fluoride (Yb3+:YLF) are used to cool an infrared HgCdTe sensor payload to an absolute temperature below 135 K, equivalent to delta T equal 138 K below ambient. This record level of cooling is accomplished with a single stage, in a completely vibration-free environment, with a corresponding cooling power of 190 mW. This milestone is made possible by the design and fabrication of an undoped YLF thermal link that efficiently shields the payload with a non-right angle kink from intense anti-Stokes …


Design Of A 3d Printed Bioreactor For Bone Cancer Research, Brooklyn K. Vanderwolde, Katelyn Hillson May 2020

Design Of A 3d Printed Bioreactor For Bone Cancer Research, Brooklyn K. Vanderwolde, Katelyn Hillson

The Journal of Undergraduate Research

Bone cancer is an aggressive disease and has peak occurrence during physiological stimulation of growth and aging. Astronauts who undergo long-term space missions also acquire an increased risk of bone tissue degeneration and cancer. Few in-vitro models currently exist capable of reproducing the complex microenvironment of bone tissue to support multicellular activity in a three-dimensional structure. This limits the ability to understand disease progression and develop suitable treatment strategies. Therefore, developing a bone tissue model and an associated bioreactor is critical to understand the risks associated with cancer progression and improve treatment and preventions related to those risks. The goal …


Numerical Modeling Of Magnetic Fields For Mirror Neutron Search Experiment, Adam Johnston May 2020

Numerical Modeling Of Magnetic Fields For Mirror Neutron Search Experiment, Adam Johnston

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

This paper will outline the configuration of 3D magnetic field model simulated from electric current sources using MATLAB. The model is using 3D arrays allowing for quick and accurate numerical approximations of Bio-Savart integrals, of error < , modeling the behavior of a magnetic field due to current carrying wires. We will discuss the development of a 3D magnetic field configuration produced by the current carrying wires around a large 2.5 m diameter vacuum beam tube in the proposed mirror neutron search experiment at High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). The simulations demonstrate that the magnetic field with uniformity better than ± 2.5 mG that will allow for optimal results in experiment within the controlled range of net magnetic field magnitudes |B| 500 mG and in the large vacuum tube along 20-m neutron flight path can be achieved for an approximately 6 cm radius section at the center of the tube.


Impact Resistant 3-D Printed Structures, Anna Schleper May 2020

Impact Resistant 3-D Printed Structures, Anna Schleper

The Journal of Undergraduate Research

This paper discusses the impact resistance of the mantis shrimp structure. Using past studies, an experiment was performed to identify an optimal wall thickness of a modified mantis shrimp structure. Various samples were 3-D printed using PLA and subjected to compression testing. Analysis of the data resulted in the finding that a wall thickness of 1.4 mm is the optimal thickness to obtain a lightweight, but impact resistant structure. These results are discussed further, along with any limitations of the findings.


Spaspace Humidity Control Through A Single Speed Versus A Variable Speed Hvac Solution, Koukouni P. Kone May 2020

Spaspace Humidity Control Through A Single Speed Versus A Variable Speed Hvac Solution, Koukouni P. Kone

Mechanical Engineering Theses

Conventional air conditioning systems in houses respond to thermal loads by means of controlling dry-bulb temperature through the thermostat. As part of the process of conditioning the air, dehumidification is also provided. However, as houses are becoming more efficient, supplemental dehumidification is often necessary in homes located in hot and humid climates to control relative humidity intentionally. This study compared the dehumidification performance of three residential air conditioning systems: a system with a variable speed mode (VSPD), a system with an enhanced dehumidification mode activated (Enhanced Dehum), and a system without enhanced dehumidification capabilities (Normal Cooling). The research facility was …


Concentrating Photovoltaic Retrofit For Existing Parabolic Trough Solar Collectors: Design, Experiments, And Levelized Cost Of Electricity, Todd P. Otanicar, Rhetta Wingert, Matthew Orosz, Clay Mcpheeters May 2020

Concentrating Photovoltaic Retrofit For Existing Parabolic Trough Solar Collectors: Design, Experiments, And Levelized Cost Of Electricity, Todd P. Otanicar, Rhetta Wingert, Matthew Orosz, Clay Mcpheeters

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Photovoltaics and concentrating solar thermal power are two ways for generating electricity from sunlight, albeit through different methods. Parabolic trough style powerplants represent 3.6 GW of electricity production, but many of these plants are aging and being replaced with photovoltaics. An alternative option that could be employed to leverage the sunk capital cost associated with the primary optics would be the design of a pure photovoltaic retrofit working within the existing plant architecture. Here, a secondary optical concentrator is designed to use the existing primary optics of a parabolic trough type solar thermal powerplant. The design is a v-shaped secondary …