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Full-Text Articles in Mechanical Engineering

Improving The Piezoelectric Properties Of Flexible Polymer-Nanoparticle Energy Harvesters, Muhammet Emin Cavusoglu Jun 2020

Improving The Piezoelectric Properties Of Flexible Polymer-Nanoparticle Energy Harvesters, Muhammet Emin Cavusoglu

Theses and Dissertations

In this research, one of the widely used polymers, poly(vinylidene fluoride)(PVDF), was used to develop thin-film polymer energy harvesters. Dimethylformamide (DMF) and methyl ethyl ketone (MEK) were used to dissolve the PVDF powder. Four different (0%, 3%, 5%, and 7%) ZnO nanoparticle (NP) concentrations were used to enhance the electrical output of the thin-film energy harvesters. A sonication bath and additional MEK were used in dispersing the ZnO NPs to obtained uniform PVDF/ZnO NP solution. The electrode poling technique was used for dipole alignment to improve the electrical performance of the devices. The fabricated samples were tested ...


Integrated Resource Plan For Portland General Electric (Pge), Mary Biswal, Alejandro Castelan May 2020

Integrated Resource Plan For Portland General Electric (Pge), Mary Biswal, Alejandro Castelan

Master's Projects and Capstones

An integrated resource plan (IRP) for Portland General Electric (PGE) is developed in this master’s project. The IRP is based on capacity expansion modeling for zero-carbon emission scenarios. PGE is a public electric utility based in Oregon and serves around 887,000 customers across a territory of 4,000 sq. miles. The utility’s resource mix is currently heavily dependent on natural gas making up almost 50% of its capacity. While the state renewable portfolio standards (RPS) require Oregon power utilities to derive 50% of their generation from renewable sources by 2040, PGE plans to move rapidly into a ...


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 ...


An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald May 2020

An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald

Honors Scholar Theses

The purpose of this project is to design a clean energy-sourced microgrid for UConn’s main campus that would reduce the university’s energy emissions while remaining within the geographic boundaries of viable UConn-owned land. Economic cost was not considered in this analysis; instead, emissions and space constraints were the optimized measures of value and feasibility. Sources of energy that were considered include photovoltaics (PV), wind turbines, hydrokinetic systems, and fuel cells. Energy storage capacity was included in the analysis as well. The overall system was optimized first by ignoring space constraints and for a minimum of 10% reduction from ...


Adaptable Clean Energy Laboratory, Joao Marcelo Rocha Belmonte, Marc D. Compere Jan 2020

Adaptable Clean Energy Laboratory, Joao Marcelo Rocha Belmonte, Marc D. Compere

Sustainability Conference

The Adaptable Clean Energy (ACE) Lab is a real-world, long term, test platform that will guide the courses of the Energy Systems track. The lab will provide realistic electrical and HVAC loads that mimic a solar powered office. The lab is a 20’ high cube shipping container modified with a door, windows, lights computers, air conditioner and appliances. The lab is Net-Zero and powered entirely from the sun. Two insulation test sections expose the exterior walls for research access to real external heat loads in a real building


Dual-Axis Solar Tracker, Bryan Kennedy Jan 2020

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in ...


Hvac System Energy Audit For Leverett Elementary School, Connor Smalling Dec 2019

Hvac System Energy Audit For Leverett Elementary School, Connor Smalling

Biological and Agricultural Engineering Undergraduate Honors Theses

Leverett Elementary School is located in Fayetteville, AR. The school needs significant upgrades to its infrastructure. The Fayetteville Public School District has voted to pursue an Energy Services Performance Contract (ESPC) in order to finance the desired upgrades to Leverett Elementary, among other schools in the district.

The scope of this thesis was to perform an energy audit on the existing heating, ventilation, and air conditioning (HVAC) system. By using an energy modeling software, eQuest, the building and the existing base system were modeled to determine utility consumption. Three different HVAC system alternatives were analyzed against the base system by ...


Swarm Behavior To Mitigate Rebound In Air Conditioning Demand Response Events, Jason Yasuto Kuwada Aug 2019

Swarm Behavior To Mitigate Rebound In Air Conditioning Demand Response Events, Jason Yasuto Kuwada

Boise State University Theses and Dissertations

Thermostatically Controlled Loads (TCLs) have shown great potential for Demand Response (DR) events. However, it has been commonly seen that DR events using TCLs may cause demand rebound, especially in homogeneous populations. To further explore the potential for DR events, as well as the negative effects, a stability and resilience analysis were performed on multiple populations and verified with agent based modeling simulations.

At the core of this study is an added thermostat criterion created from the combination of a proportional gain and the average compressor operating state of neighboring TCLs. Where DR events in TCLs are commonly controlled by ...


Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James Aug 2019

Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James

All Graduate Theses and Dissertations

Expanders allow pressurized fluids to undergo a pressure decrease in a controlled environment via volumetric growth to extract fluid energy. There are many types of expanders, and the objective of this thesis is to model the efficiencies of the planetary rotor expander (PRE), a century-old design undeveloped due to insufficient manufacturing capabilities (until recently). Geometric relationships are derived and mathematical models are generated to determine the efficiency of the PRE as a function of design variables. Two industrially relevant case studies show that, to maximize isentropic efficiency, the planetary rotor expander (PRE) rotational frequency is maximized and rotor geometry optimized.


Numerical Investigation Of Coalescence-Induced Self-Propelled Behavior Of Droplets On Non-Wetting Surfaces And Wedged Surfaces., Yan Chen May 2019

Numerical Investigation Of Coalescence-Induced Self-Propelled Behavior Of Droplets On Non-Wetting Surfaces And Wedged Surfaces., Yan Chen

Electronic Theses and Dissertations

When small drops coalesce on a superhydrophobic surface, the merged drop can jump away from the surface due to the surface energy released during the coalescence. This self-propelled behavior has been observed on various superhydrophobic surfaces and has potential applications in areas related to the heat and mass transfer, such as heat exchangers, anti-icing and anti-frost devices, thermal management and water harvesting. The jumping velocity model was obtained based on published experimental data and the balance of various energy terms described in previous studies. However, the self-propelled mechanism is still not fully understood. In this study, the self-propelled droplet phenomenon ...


Dual Axis Solar Tracker: Trends, Influence & Impact, Alazone Smith Jan 2019

Dual Axis Solar Tracker: Trends, Influence & Impact, Alazone Smith

Undergraduate Honors Theses

This supplementary document examines the international relevance and impact of the device in the Central Washington University, M.E.T. Senior Project entitled, “Dual-Axis Solar Tracker”. This is done so by analyzing the data collected from the device, as well as related trends in society, and establishing connections between the device’s viability and its impact within the society. Climate change, the solar industry, technology, policy, and market are the main topics of research within this document to provide background and context for the methods of analysis. Following intensive research, two major research strategies were implemented: (1) the data collected ...


Design Of Wind Turbine Tower Height And Blade Length: An Optimization Approach, Ryan Wass Sep 2018

Design Of Wind Turbine Tower Height And Blade Length: An Optimization Approach, Ryan Wass

Mechanical Engineering Undergraduate Honors Theses

The wind industry is a fast growing market and is quickly becoming competitive with traditional non-renewable energy resources. As with any developing industry, research must continually be redefined as more complex understandings of design variables are learned. Optimization studies are common ways to quickly refine design variable selections. Historical wind turbine data shows that the tower hub height to rotor diameter ratio scales almost linearly. However there is no specific rule that dictates the optimum hub height for a given diameter. This study addresses this question by using an Excel based optimization program to determine the height to diameter ratio ...


Thermophotovoltaic Devices: Combustion Chamber Optimization And Modelling To Maximize Fuel Efficiency, Arnold Chris Toppo, Ernesto Marinero, Zhaxylyk Kudyshev Aug 2018

Thermophotovoltaic Devices: Combustion Chamber Optimization And Modelling To Maximize Fuel Efficiency, Arnold Chris Toppo, Ernesto Marinero, Zhaxylyk Kudyshev

The Summer Undergraduate Research Fellowship (SURF) Symposium

Currently, 110 billion cubic meters of natural gas (primarily methane), a potent greenhouse gas, are flared off for environmental and safety reasons. This process results in enough fuel to provide the combined natural gas consumption of Germany and France. The research team developed a thermophotovoltaic device to convert thermal energy to electricity at a high efficiency using proprietary emitters and combustion system. With the current focus being fuel efficiency and the combustion process, the assembly was simulated using ANSYS Fluent modelling software and the following parameters were optimized: air/fuel ratios, flow rates, and inlet sizes. Simultaneously the heat transfer ...


Applications Of Latent Heat Storage Using Phase Change Materials, Daniel Giroux Jun 2018

Applications Of Latent Heat Storage Using Phase Change Materials, Daniel Giroux

Honors Theses

Thermal Storage Systems are gaining more attention in recent years with the increased emphasis on more renewable energy sources. Energy storage is necessary whenever there is greater amounts of energy being produced than is required. Various improvements to the conventional heat storage system can be made by integrating latent heat storage into the conventional heat storage system. Latent heat storage can be utilized for thermal storage applications by using phase change materials, materials that will undergo a change in their physical state in the temperature range desired for heat storage.

Analysis was conducted on four different waxes considering the waxes ...


Single-Stage, Venturi-Driven Desalination System, Brandon Proetto May 2018

Single-Stage, Venturi-Driven Desalination System, Brandon Proetto

Mechanical & Aerospace Engineering Theses & Dissertations

Water demand is increasing at a rapid pace due to population increase, industrial expansion, and agricultural development. The use of desalination technology to meet the high water demands has increased global online desalination capacity from 47 million m^3/d in 2007 to 92.5 million m^3/d as of June 2017 [49]. Membrane and thermal processes are the two mainstream desalination categories used worldwide for desalination plants. Reverse Osmosis (RO) is the most widely used membrane process and it has become the dominant technology for building desalination plants over recent decades. Thermal distillation, however, has become less and ...


Simulation Of The Inertia Friction Welding Process Using A Subscale Specimen And A Friction Stir Welder, Ty Samual Dansie Apr 2018

Simulation Of The Inertia Friction Welding Process Using A Subscale Specimen And A Friction Stir Welder, Ty Samual Dansie

Theses and Dissertations

This study develops a method to simulate a full-scale inertia friction weld with a sub-scale specimen and modifies a direct drive friction stir welder to perform the welding process. A torque meter is fabricated for the FSW machine to measure weld torque. Machine controls are modified to enable a force control during the IFW process. An equation is created to measure weld upset due to deflection of the FSW machine. Data obtained from a full-scale inertia friction weld are altered to account for the geometrical differences between the sub-scale and full-scale specimens. The IFW are simulated with the sub-scale specimen ...


An Examination Of Ash Elutriation From A Fluidized Bed Regenerator, Dane Erickson Jan 2018

An Examination Of Ash Elutriation From A Fluidized Bed Regenerator, Dane Erickson

Graduate Theses and Dissertations

The danger of climate change looms in the minds of researchers across the world. To combat this threat, many have focused efforts on the development of clean energy. In this study, the renewable resource that is investigated is biomass, specifically red oak. Energy can be extracted from biomass by fast pyrolysis, where the feedstock is rapidly heated within a reactor to approximately 500℃ in the absence of oxygen. This produces biochar, ash, and condensable gases that, once cooled, become a bio-oil. To optimize economic feasibility, the process must operate continuously. This presents a problem—the presence of ash as a ...


Dynamic Rops Test For Tractors Over 6,000 Kilograms, Caleb M. Lindhorst, Roger M. Hoy, Santosh Pitla, Michael F. Kocher Jan 2018

Dynamic Rops Test For Tractors Over 6,000 Kilograms, Caleb M. Lindhorst, Roger M. Hoy, Santosh Pitla, Michael F. Kocher

Biological Systems Engineering: Papers and Publications

OECD static tests (Codes 4, 6, 7, and 8) for agricultural rollover protective structures (ROPS) have become accepted standards for evaluating the ability of these structures to protect the operator during tractor rollover events. The strength properties of some materials typically used in ROPS change because of cold weather embrittlement at low temperatures. The static ROPS tests lack the ability to evaluate the strength of these structures during cold weather. The use of the dynamic ROPS test is well noted as a means for proving cold weather embrittlement resistance properties. Unfortunately, application of the OECD dynamic ROPS test (Code 3 ...


Energy Potentials Of Briquette Produced From Tannery Solid Waste, Olatunde Ajani Oyelaran, Faralu Muhammed Sani, Olawale Monsur Sanusi, Olusegun Balogun, Adeyinka Okeowo Fagbemigun Dec 2017

Energy Potentials Of Briquette Produced From Tannery Solid Waste, Olatunde Ajani Oyelaran, Faralu Muhammed Sani, Olawale Monsur Sanusi, Olusegun Balogun, Adeyinka Okeowo Fagbemigun

Makara Journal of Technology

The vast quantity of waste generated from industries is one of the serious outcomes of unplanned development, resulting into quantum of hazardous organic and inorganic waste generating daily. Proper waste management is a challenging issue that must be addressed adequately. This is, therefore, carried out with a view of assessing the energy and combustion quality of tannery solid waste with a view of converting them into briquettes for cooking, heating and small home industries and reducing the menace caused by tannery waste disposal. The results of the experiments showed that the combustion rate ranged between 0.171 and 0.217 ...


Proton Transfer In Molten Lithium Carbonate: Mechanism And Kinetics By Density Functional Theory Calculations, Xueling Lei, Kevin Huang, Changyong Qin Aug 2017

Proton Transfer In Molten Lithium Carbonate: Mechanism And Kinetics By Density Functional Theory Calculations, Xueling Lei, Kevin Huang, Changyong Qin

Faculty Publications

Using static and dynamic density functional theory (DFT) methods with a cluster model of [(Li2CO3)8H]+, the mechanism and kinetics of proton transfer in lithium molten carbonate (MC) were investigated. The migration of proton prefers an inter-carbonate pathway with an energy barrier of 8.0 kcal/mol at the B3LYP/6-31 G(d,p) level, which is in good agreement with the value of 7.6 kcal/mol and 7.5 kcal/mol from experiment and FPMD simulation, respectively. At transition state (TS), a linkage of O–H–O involving O 2p and H 1 s orbitals is formed between ...


Suspended Graphene-Based Gas Sensor With 1-Mw Energy Consumption, Jong-Hyun Kim, Qin Zhou, Jiyoung Chang Jan 2017

Suspended Graphene-Based Gas Sensor With 1-Mw Energy Consumption, Jong-Hyun Kim, Qin Zhou, Jiyoung Chang

Mechanical & Materials Engineering Faculty Publications

This paper presents NH3 sensing with ultra-low energy consumption for fast recovery and a graphene sheet based on a suspended microheater. Sensitivity and repeatability are important characteristics of functional gas sensors embedded in mobile devices. Moreover, low energy consumption is an essential requirement in flexible and stretchable mobile electronics due to their small dimension and fluctuating resistivity during mechanical behavior. In this paper, we introduce a graphene-based ultra-low power gas detection device with integration of a suspended silicon heater. Dramatic power reduction is enabled by a duty cycle while not sacrificing sensitivity. The new oscillation method of heating improves ...


Dynamic Behavior Of A Clamped-Clamped Bi-Stable Laminate For Energy Harvesting, Ajay V. Kumar, Andres F. Arrieta Ph.D., Myungwon Hwang Aug 2016

Dynamic Behavior Of A Clamped-Clamped Bi-Stable Laminate For Energy Harvesting, Ajay V. Kumar, Andres F. Arrieta Ph.D., Myungwon Hwang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Multi-stable laminates have many applications in morphing structures, energy harvesting devices, and metamaterials due to the specific characteristics attributed to the exhibited stable states. Changes between stable states allow for large deflections, on-demand variation of the stiffness of compliant structures embedded within these elements, and control of effective dynamic properties in periodic lattices. These changes in state can be accessed via a snap-through instability triggered by introducing a well-defined activation energy. The resulting oscillations could enable broadband energy harvesting via piezoelectric transduction and resistive circuits. In this paper, a clamped-clamped bi-stable laminate is studied to understand the behavior of the ...


Parametric And Design Analysis On Thermoelectric Generators, Shouyuan Huang Aug 2016

Parametric And Design Analysis On Thermoelectric Generators, Shouyuan Huang

Open Access Theses

In facing the limited energy source reserves and environmental problems, thermoelectric generators (TEGs) are one of the promising waste heat recovery systems. The modern TEGs for exhaust stream (e.g. from automobiles) can improve the fuel economy by around 5%, taking advantage of the recent developed thermoelectric (TE) materials.

In this work, we aimed at designing a TEG as an add-on module for a gas-phase heat exchanger with maximized power output, and without negative impact (e.g. maintaining a minimum heat dissipation rate from the hot side). We first developed a parametric optimization algorithm using response surface method (RSM) and ...


Strain Energy Absorption Corresponds To Decreased Incidence Of Ventricular Fibrillation In A Commotio Cordis Model, Kayt E. Frisch, Mark S. Link, John Van Weelden Aug 2016

Strain Energy Absorption Corresponds To Decreased Incidence Of Ventricular Fibrillation In A Commotio Cordis Model, Kayt E. Frisch, Mark S. Link, John Van Weelden

Faculty Work Comprehensive List

A healthy teenage boy is playing high school baseball, when he is struck in the chest by the ball; minutes later, his heart is experiencing ventricular fibrillation (VF) and the only way to resuscitate him is to use a defibrillator. This phenomenon, is known as Commotio Cordis (CC), and occurs as many as 20 times each year in the United States. CC most frequently occurs in sports with small balls (e.g. baseball or lacrosse) and requires a specific set of circumstances–a projectile with a certain amount of energy that impacts directly over the left ventricle of the heart ...


Second Law Of Thermodynamics Analysis Of An Internal Combustion Engine Fueled With Methane, Abotabik Aug 2016

Second Law Of Thermodynamics Analysis Of An Internal Combustion Engine Fueled With Methane, Abotabik

Master's Theses

The second law of thermodynamics is a powerful tool for calculating the amount of energy that can be converted to work (i.e., the exergy or availability of a system), which cannot be predicted using the first law. The objectives of this research project are to quantify the availability during the compression, combustion and expansion processes of a spark-ignited engine fueled with methane; and to highlight differences in the thermo-mechanical availability of the ideal and spark-ignition (SI) engine cycles. A cooperative single-cylinder research engine was used to measure the data required for availability analysis at equivalence ratios ranging between 0 ...


Using The Moment Of Inertia As A Means Of Better Controlling The Speed Of Wind Turbines, Garrett L. Muhlstadt Mar 2016

Using The Moment Of Inertia As A Means Of Better Controlling The Speed Of Wind Turbines, Garrett L. Muhlstadt

Honors Program Projects

In the following document, the possibility of using the moment of inertia as a means of speed control for a wind turbine is explored. This document gives an introduction to wind energy and current speed control methods. This information was obtained through databases found at Benner Library. Also, an experiment was used to collect data and determine the relationship between the moment of inertia and angular velocity of a turbine. A model turbine was fabricated and powered by a fan while a Logger Pro program was used to record the angular velocity of the turbine. The moment of inertia of ...


Cogeneration System Comparison For The Akron Water Treatment Plant, Devin J. Pearcy, Madison R. Morgan Jan 2016

Cogeneration System Comparison For The Akron Water Treatment Plant, Devin J. Pearcy, Madison R. Morgan

Williams Honors College, Honors Research Projects

Cogeneration is a process of electrical power generation that simultaneously harnesses the heat produced from that electrical generation and uses it to supply heat to a space. The Akron Water Plant was identified as potentially benefitting from this technology for two main reasons. First, they have a large and relatively constant electrical load. Second, they have ownership of a significant amount of natural gas wells at the site.

This report analyzes the economic feasibility of installing a cogeneration plant at the Akron Water Plant (AWP). Data was collected for the plant and its operations, including electricity bills, gas bills, plant ...


Hybrid Diesel-Electric Drivetrain For Small Agricultural Field Machines, Joseph Jackson, Joseph S. Dvorak Jan 2016

Hybrid Diesel-Electric Drivetrain For Small Agricultural Field Machines, Joseph Jackson, Joseph S. Dvorak

Biosystems and Agricultural Engineering Faculty Publications

In this project, a series electric drivetrain sized for small agricultural machinery was developed and tested. Electric drives have noted benefits in simplicity, controllability, integration with other electronics such as those that provide autonomous action, and in efficiency over a wide operating range. Their biggest drawback for agricultural use is the limited capacity of electrical energy storage. A series hybrid drivetrain provides a method to overcome these capacity constraints through the use of chemical energy storage. The series hybrid drivetrain in this research was designed using well-established components. It consisted of a diesel-electric generator, a lead acid battery pack, a ...


Wind Turbine Towers: Precast Concrete Hexcrete May Help Increase Renewable Energy Capacity With Taller Hub Height, Sri Sritharan Nov 2015

Wind Turbine Towers: Precast Concrete Hexcrete May Help Increase Renewable Energy Capacity With Taller Hub Height, Sri Sritharan

Civil, Construction and Environmental Engineering Publications

Wind-energy production has been growing rapidly in the Midwest, but not in other regions of the United States. Increased wind-turbine hub heights of 328 to 459 ft (100 to 140 m) could drastically change this. As wind-turbine towers get taller than 263 ft (80 m), a concrete solution may become more cost-effective than the steel tubular option. The Hexcrete concept was developed with the aim of revolutionizing wind-turbine towers for hub heights of 328 ft (100 m) and more. This tower uses hexagonal columns with posttensioning and rectangular/tapered panels as bracing elements. The prefabricated modules are assembled using posttensioning ...


Veloelectric: Creating A Device That Harvests Energy From Bicycles, Austin Hall, Daniel Stohr, Tj Fox Jun 2015

Veloelectric: Creating A Device That Harvests Energy From Bicycles, Austin Hall, Daniel Stohr, Tj Fox

Mechanical Engineering

Long distance mountain bikers, bike-packers, and many bikers in developing countries rely on electrical devices for safety and communication. These specific groups of people operate in areas with little to no electricity, and often times have no power to sustain their devices. The purpose of this Cal Poly senior project, VeloElectric, was to design, build, and test a kinetic energy harvester for bicycles that can be used to charge common mobile devices via USB. This senior project team created a device that attaches directly to a bicycle and uses vibrations to generate energy, which in turn powers a variety of ...