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Full-Text Articles in Mechanical Engineering

Seawater Distiller (Solar Collector For Heating Seawater), Ali Alismail Jan 2018

Seawater Distiller (Solar Collector For Heating Seawater), Ali Alismail

All Undergraduate Projects

Many people in the world globally have limited or no access to clean drinking water. Unclean drinking water is a major cause of deadly diseases such as typhoid, cholera, and other water-borne diseases. The motivation of this report aims to document a senior project to satisfy for the award of MET by CWU. The aim was to design and manufacture a solar thermal collector capable of heating water using solar energy. The solar collector was developed by designing and fabricating a parabolic reflective surface. The reflective surface was manufactured from a reflective stainless-steel sheet. The advantages of using a parabolic …

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Cassette Lockring Removal Tool, Kyle Wright Jan 2018

Cassette Lockring Removal Tool, Kyle Wright

All Undergraduate Projects

Removal of a bicycle cassette requires additional tools to hold the cassette in place while loosening the cassette lockring. Typically a tool called a chain whip is used to stabilize the cassette, but is difficult to quickly and correctly apply to the cassette. Due to the need for an additional tool to hold the cassette, the user is faced with utilizing both hands while still needing to somehow hold the wheel in place. The lockring is torqued relatively tight and the overall combination of force, ergonomics, and number of tools required makes the task difficult to perform quickly. The objective …

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H.F. Hauff Pruner Cutting Blades, Wyley Stewart Jan 2018

H.F. Hauff Pruner Cutting Blades, Wyley Stewart

All Undergraduate Projects

Apple orchards are a critical component of agriculture in the United States, and keeping the apple trees in the best shape for optimum growth and production is hard work. Neil Hauff, an agriculture industry expert, challenged students at CWU to engineer a power assisted tree pruner. Across the country, apple orchards need pruned every season. The pruning of the trees is strenuous manual labor that requires many man hours. The proposed solution is to create a power assisted tree pruner that would minimize the amount of work needed to trim each tree branch. This project has been separated into three …

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Mechanical Properties Of The Skeleton Of Acropora Cervicornis, Bridget Masa Jan 2018

Mechanical Properties Of The Skeleton Of Acropora Cervicornis, Bridget Masa

Honors Undergraduate Theses

This research explores the instantaneous mechanical behavior of the skeleton of the critically endangered staghorn coral Acropora cervicornis. Both bleached and sanded skeletons were used in this experiment. The Raman spectroscopy test showed that there was no significant change in the Raman shift between the three branches tested. The shifts were nearly identical to Raman shifts of calcium carbonate. Vickers hardness test found that 1 Bleached had the average hardness of 3.44 GPa with a standard deviation of 0.12 GPa. The sanded sample also had a similar value of 3.54 GPa with a standard deviation of 0.13 GPa. Samples from …

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Electrostatic Potential And Valence Modulation In La0.7sr0.3mno3 Thin Films, Robbyn Trappen, A. C. Garcia- Castro, Vu Thanh Tra, Chih-Yeh Huang, Wilfredo Ibarra-Hernandez, James Fitch, Sobhit Singh, Jingling Zhou, Guerau Cabrera, Ying-Hao Chu, James M. Lebeau, Aldo H. Romero, Mikel B. Holcomb Jan 2018

Electrostatic Potential And Valence Modulation In La0.7sr0.3mno3 Thin Films, Robbyn Trappen, A. C. Garcia- Castro, Vu Thanh Tra, Chih-Yeh Huang, Wilfredo Ibarra-Hernandez, James Fitch, Sobhit Singh, Jingling Zhou, Guerau Cabrera, Ying-Hao Chu, James M. Lebeau, Aldo H. Romero, Mikel B. Holcomb

Faculty & Staff Scholarship

The Mn valence in thin film La0.7Sr0.3MnO3 was studied as a function of film thickness in the range of 1–16 unit cells with a combination of non-destructive bulk and surface sensitive X-ray absorption spectroscopy techniques. Using a layer-by-layer valence model, it was found that while the bulk averaged valence hovers around its expected value of 3.3, a significant deviation occurs within several unit cells of the surface and interface. These results were supported by first principles calculations. The surface valence increases to up to Mn3.7+, whereas the interface valence reduces down to Mn2.5+. The change in valence from the expected …

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Enhancement Of Performance Of Micro Direct Ethanol Fuel Cells By Structural Modification, Sindhuja Valluri Jan 2018

Enhancement Of Performance Of Micro Direct Ethanol Fuel Cells By Structural Modification, Sindhuja Valluri

Masters Theses

“Direct Ethanol Fuel Cells (DEFC’s) are becoming more important in current energy conversion devices because of their higher efficiency compared to other fuel cells. However, the performance of current DEFC’s is not efficient in providing energy to meet increasing energy demand. The objective of this work is to make the cell compact and at the same time improve performance. For this purpose, we have removed gasket and endplates to make structure compact and increased surface area by developing a new corrugated structure. This work also uses 3D printing technology Fused Deposition Modeling (FDM) to make pocket backing case to improve …

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Pressure Image Based Attitude Controller For Small Unmanned Aerial Vehicles, Kenneth Thompson Jan 2018

Pressure Image Based Attitude Controller For Small Unmanned Aerial Vehicles, Kenneth Thompson

Electronic Theses and Dissertations

As technology improves, small unmanned aerial vehicles (SUAV) have been identified for their utility in a variety of applications in which larger unmanned craft may be incapable of accomplishing mission objectives. These aircraft with their small size and long flight durations are ideal for hazardous inspection and long duration surveillance missions. One challenge preventing the widespread adoption of these systems is their instability to abrupt changes in the flow field around them due to wind gusts or flow separation. Currently, traditional rigid body based sensors are implemented in their flight control systems, which are sufficient in higher inertia aircraft for …

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Experimental Investigation Of Advanced Ignition Systems For High Efficiency Combustion, Bader Almansour Jan 2018

Experimental Investigation Of Advanced Ignition Systems For High Efficiency Combustion, Bader Almansour

Electronic Theses and Dissertations

Consumption of fossil and bio-derived fuels is growing due to energy demands associated with increase in population and standard of living across the globe. Power generation and transportation sectors are the primary two sources of fuel consumption, which have raised the demand for crude oil and led to serious environmental pollution issues. This demand for energy forced various government agencies to strengthen the allowable exhaust pollutant concentration limits. Recently, CO, CO2, particulate matter, and nitrogen oxides (NOx) emission restrictions have become more stringent to the extent that engines must operate at higher energy densities and efficiencies. Towards this goal, this …

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Radial And Longitudinal Motion Of The Arterial Wall: Their Relation To Pulsatile Pressure And Flow In The Artery, Dan Wang, Linda Vahala, Zhili Hao Jan 2018

Radial And Longitudinal Motion Of The Arterial Wall: Their Relation To Pulsatile Pressure And Flow In The Artery, Dan Wang, Linda Vahala, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

The aim of this paper is to analyze the radial and longitudinal motion of the arterial wall in the context of pulsatile pressure and flow, and to understand their physiological implications for the cardiovascular system. A reexamination of the well-established one-dimensional governing equations for axial blood flow in the artery and the constitutive equation for the radial dilation of the arterial wall shows that two waves—a pulsatile pressure wave in the artery and a radial displacement wave in the arterial wall—propagate simultaneously along the arterial tree with the same propagation velocity, explaining why this velocity combines the physical properties and …

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A Modeling Framework Of Brittle And Ductile Fractures Coexistence In Composites, Yangyang Qiao Jan 2018

A Modeling Framework Of Brittle And Ductile Fractures Coexistence In Composites, Yangyang Qiao

Electronic Theses and Dissertations

In order to reduce the weight of automobiles and aircrafts, lightweight materials, such as aluminum alloy, advanced high strength steel, composite materials, are widely used to replace the traditional materials like mild steel. Composite materials are complicated in material mechanical properties and less investigated compared to metallic materials. Engineering composites can be categorized into polymer matrix composites (PMCs), metal matrix composites (MMCs) and ceramic matrix composites (CMCs) according to their matrix materials. A set of mechanical experiments ranging from micro scale (single fiber composite and thin film composite) to macro scale (PMCs and MMCs) were conducted to fully understand the …

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Investigation Into The Feasibility Of Adding Turbulators To Rocket Combustion Chamber Cooling Channels Using A Conjugate Heat Transfer Analysis, Tyler Buchanan Jan 2018

Investigation Into The Feasibility Of Adding Turbulators To Rocket Combustion Chamber Cooling Channels Using A Conjugate Heat Transfer Analysis, Tyler Buchanan

Electronic Theses and Dissertations

A conjugate heat transfer analysis will be carried out to simulate an 89 kN thrust chamber hydrogen cooling channel, to determine the feasibility of adding turbulators to the combustion chamber cooling channels at various parameters such as angle, pitch, and height of the turbulator. An existing regeneratively cooled chamber environment is simulated and used as a baseline case to be compared against. The new design includes using ribbed turbulators or delta wedges in the cooling channels to increase the heat transfer on the channel hot wall (wall adjacent to the hot gas wall) and on the two channel sidewalls. With …

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Nondestructive Testing Methods Aided Via Numerical Computation Models For Various Critical Aerospace Power Generation Systems, Peter Warren Jan 2018

Nondestructive Testing Methods Aided Via Numerical Computation Models For Various Critical Aerospace Power Generation Systems, Peter Warren

Electronic Theses and Dissertations

A current critical necessity for all industries which utilize various equipment that operates in high temperature and extreme environments, is the ability to collect and analyze data via non destructive testing (NDT) methods. Operational conditions and material health must be constantly monitored if components are to be implemented precisely to increase the overall performance and efficiency of the process. Currently in both aerospace and power generation systems there are many methods that are being employed to gather several necessary properties and parameters of a given system. This work will focus primarly on two of these NDT methods, with the ultimate …

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The Study Of An Impinging Unsteady Jet - Fluid Mechanics And Heat Transfer Analysis, Andrea Osorio Jan 2018

The Study Of An Impinging Unsteady Jet - Fluid Mechanics And Heat Transfer Analysis, Andrea Osorio

Electronic Theses and Dissertations

The high heat transfer capabilities of impinging jets have led to their widespread use in industrial applications, such as gas turbine cooling. These impinging jets are usually manufactured on the walls of super-alloy metals and are influenced by being positioned with a confined setting. Studies have been shown to enhance the heat transfer of impinging jets by fluctuating the flow which will be analyzed in this project with two designs. The first design is a self-sustaining stationary fluidic oscillator that causes a sweeping motion jet to impinge on the surface. This is investigated using Particle Image Velocimetry (PIV) to study …

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Navigation Of An Autonomous Differential Drive Robot For Field Scouting In Semi-Structured Environments, Douglas Freese Jan 2018

Navigation Of An Autonomous Differential Drive Robot For Field Scouting In Semi-Structured Environments, Douglas Freese

Electronic Theses and Dissertations

In recent years, the interests of introducing autonomous robots by growers into agriculture fields are rejuvenated due to the ever-increasing labor cost and the recent declining numbers of seasonal workers. The utilization of customized, autonomous agricultural robots has a profound impact on future orchard operations by providing low cost, meticulous inspection. Different sensors have been proven proficient in agrarian navigation including the likes of GPS, inertial, magnetic, rotary encoding, time of flight as well as vision. To compensate for anticipated disturbances, variances and constraints contingent to the outdoor semi-structured environment, a differential style drive vehicle will be implemented as an …

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Application Of Trained Pod-Rbf To Interpolation In Heat Transfer And Fluid Mechanics, Rebecca A. Ashley Jan 2018

Application Of Trained Pod-Rbf To Interpolation In Heat Transfer And Fluid Mechanics, Rebecca A. Ashley

Honors Undergraduate Theses

To accurately model or predict future operating conditions of a system in engineering or applied mechanics, it is necessary to understand its fundamental principles. These may be the material parameters, defining dimensional characteristics, or the boundary conditions. However, there are instances when there is little to no prior knowledge of the system properties or conditions, and consequently, the problem cannot be modeled accurately. It is therefore critical to define a method that can identify the desired characteristics of the current system without accumulating extensive computation time. This thesis formulates an inverse approach using proper orthogonal decomposition (POD) with an accompanying …

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Equibiaxial Flexural Strength Testing Of Advance Ceramics, Ryan T. Jordan Jan 2018

Equibiaxial Flexural Strength Testing Of Advance Ceramics, Ryan T. Jordan

Honors Undergraduate Theses

Ceramics are very important materials with many unique properties used in numerous industrial applications. Ceramics could be very hard and very strong in comparison to metals; however, they are very brittle, thus they are prone to instantaneous and catastrophic failure. Therefore, their reliability is compromised and it is very important to have advanced techniques that allow evaluating their mechanical behavior in many unusual stress states. One of such testing methods is biaxial strength method, that allows to measure properties not only unidirectional, but also in a biaxial way. The research work for this thesis will be built on design and …

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Stochastic Bi-Level Optimization Models For Efficient Operating Room Planning, Amin Abedini, Wei Li, Honghan Ye Jan 2018

Stochastic Bi-Level Optimization Models For Efficient Operating Room Planning, Amin Abedini, Wei Li, Honghan Ye

Mechanical Engineering Faculty Publications

Within a hospital, the operating room (OR) department has the largest cost and revenue. Because of the aging population, the demand for surgical services has been increasing sharply in recent years. At the other hand, the rate of OR capacity expansion is lower than the rate of increasing demand. As a result, OR managers must leverage their resources by efficient OR planning. OR planning is challenging because of multiple competing\conflicting objectives such cost minimization and throughput maximization. Inherent uncertainty in the surgical procedures and patients arrivals complicate the decision making process. This increases the risk of non-realization of the system …

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Turbulent Flame-Vortex Dynamics Of Bluff-Body Premixed Flames, Marissa Geikie Jan 2018

Turbulent Flame-Vortex Dynamics Of Bluff-Body Premixed Flames, Marissa Geikie

Electronic Theses and Dissertations

This study explores the effects of turbulence and pressure-gradient tailoring on the turbulent flame and vorticity transport mechanisms of premixed flames. A turbulent premixed flame stabilized by a bluff-body in a high-speed combustor is used for the investigation. The combustor pressure gradient is altered using a variable-geometry test section. The turbulence within the combustor is controlled using a custom-designed, supersonic variable-turbulence generator. The turbulent flame-flow field is measured and characterized using simultaneous high-speed particle imaging velocimetry (PIV) and CH* chemiluminescence. The flame-vortex dynamics of the turbulent flame are analyzed using a Lagrangian tracking methodology. Lagrangian fluid elements (LFEs) are tagged …

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Damage Characterization Of Aircraft Fuselage Using Vibrothermography Technique-Review And Analysis, Abbasali Saboktakin Jan 2018

Damage Characterization Of Aircraft Fuselage Using Vibrothermography Technique-Review And Analysis, Abbasali Saboktakin

International Journal of Aviation, Aeronautics, and Aerospace

Vibrothermogrphy is a promising non-destructive technique that uses ultrasonic elastic waves to detect damages and is typically applied in the aerospace and automotive industries. This technique allows for defect selective imaging using thermal waves that are generated by ultrasound waves. In this paper, vibrothermography technique was applied to the aircraft fuselage to detect its damage. The influence of the damage on the temperature distribution at the damage region on the aluminum was investigated by finite element technique. Comprehensive understanding in edge crack in fuselage heating caused by local friction between crack surfaces was obtained.

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Dust Control Examination Using Computational Fluid Dynamics Modeling And Laboratory Testing Of Vortecone And Impingement Screen Filters, Ashish R. Kumar Jan 2018

Dust Control Examination Using Computational Fluid Dynamics Modeling And Laboratory Testing Of Vortecone And Impingement Screen Filters, Ashish R. Kumar

Theses and Dissertations--Mining Engineering

Heavy industries, such as mining, generate dust in quantities that present an occupational health hazard. Prolonged exposure to the respirable dust has been found to result in many irreversible occupational ailments in thousands of miners. In underground mining applications, a variety of scrubbing systems are used to remove dust near the zones of generation. However, the wire-mesh type fibrous screens in the flooded-bed dust scrubbers used on continuous miners, are prone to clogging due to the accumulation of dust particles. This clogging results in a reduced capture efficiency and a higher exposure to the personnel. This research establishes the Vortecone, …

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An Analysis Of Common Drill Stem Vibration Models, Mohammed F. Al Dushaishi, Runar Nygaard, Daniel S. Stutts Jan 2018

An Analysis Of Common Drill Stem Vibration Models, Mohammed F. Al Dushaishi, Runar Nygaard, Daniel S. Stutts

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Excessive drill stem (DS) vibration while rotary drilling of oil and gas wells causes damages to drill bits and bottom hole assemblies (BHAs). In an attempt to mitigate DS vibrations, theoretical modeling of DS dynamics is used to predict severe vibration conditions. To construct the model, decisions have to be made on which beam theory to be used, how to implement forces acting on the DS, and the geometry of the DS. The objective of this paper is to emphasize the effect of these assumptions on DS vibration behavior under different, yet realistic, drilling conditions. The nonlinear equations of motion …

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Pico Grid-Smart Home Energy Management System, Kristina Istre, James E. Conaway Mr. Jan 2018

Pico Grid-Smart Home Energy Management System, Kristina Istre, James E. Conaway Mr.

ENgaging Educators in Renewable enerGY (ENERGY): Lesson Plans & Slideshows (2017-2019)

No abstract provided.

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Experimental Study On Surface Integrity Of Cryogenically Machined Ti-6al-4v Alloy For Biomedical Devices, M. Hardt, F. Klocke, B. Döbbeler, M. Binder, Ibrahim S. Jawahir Jan 2018

Experimental Study On Surface Integrity Of Cryogenically Machined Ti-6al-4v Alloy For Biomedical Devices, M. Hardt, F. Klocke, B. Döbbeler, M. Binder, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

Titanium and its alloys are widely used in the biomedical sector. In this field, titanium and its alloys are the material of choice for biomedical devices such as hip and knee replacements. Usually, a Total Hip Replacement (THR) is based on four components, made out of different materials due to the material properties associated with the functional performance. One approach to lower the overall manufacturing costs and enhance the reliability of THR’s is to manufacture the prosthesis out of one material. The titanium alloy Ti-6Al-4V is, therefore, feasible as it exhibits better osseous integration compared to other metallic materials used …

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In Vitro Assessment Of The Effects Of Valvular Stenosis On Aorta Hemodynamics And Left Ventricular Function, Ashish Madan Jan 2018

In Vitro Assessment Of The Effects Of Valvular Stenosis On Aorta Hemodynamics And Left Ventricular Function, Ashish Madan

Browse all Theses and Dissertations

Calcific aortic stenosis (CAS) is the most common valvular heart disease and is associated with aortopathy and ventricular dysfunction. Hemodynamic alterations due CAS could affect the aorta lining (endothelium), that is in direct contact with the blood, triggering adverse biological responses that may possibly cause aortic dilation and dissection. Also, CAS could impose excessive ventricular load leading to ventricular wall thickening, thus putting an individual at a higher risk of heart attack or stroke. These pathophysiological effects of CAS are highly dependent on the degree of calcification. However, the impact of CAS development on aorta flow and left ventricular workload …

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Development Of An Indoor Multirotor Testbed For Experimentation On Autonomous Guidance Strategies, Kidus Guye Jan 2018

Development Of An Indoor Multirotor Testbed For Experimentation On Autonomous Guidance Strategies, Kidus Guye

Electronic Theses and Dissertations

Despite the vast popularity of rotary wing unmanned aerial vehicles and research centres that develop their guidance software, there are only a limited number of references that provide an exhaustive description of a step-by-step procedure to build-up a multirotor testbed. In response to such need, the first part of this thesis aims to describe, in detail, the complete procedure to establish and operate an autonomous multirotor unmanned aerial vehicle indoor experimental platform to test and validate guidance, navigation and control strategies. Both hardware and software aspects of the testbed are described to offer a complete understanding of the different aspects. …

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Lcd 3d Printing Of A Photocurable Elastomer For Tissue Engineering, Beatriz Luiza De Souza Jan 2018

Lcd 3d Printing Of A Photocurable Elastomer For Tissue Engineering, Beatriz Luiza De Souza

Electronic Theses and Dissertations

Three-dimensional scaffolding is an emerging research area in biomedical and tissue engineering. Scaffolds provide the possibility of growing tissues in a controlled environment, with desired characteristics and properties towards a specific application. A new method to 3D print biodegradable and biocompatible material called Polyglycerol Sebacate Acrylate (PGSA) is demonstrated. PGSA is essentially an acrylated form of PGS using photoinitiator to become a photocurable resin suitable for liquid crystal display (LCD) 3D printing. PGSA was selected because its rheological and crosslinking behavior (and hence its mechanical properties) can be controlled by changes in curing time, temperature, and pressure. This material has …

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Optimization Of Microfluidic Particle Separator Geometry Using Computational Fluid Dynamics, Joseph Petersen Jan 2018

Optimization Of Microfluidic Particle Separator Geometry Using Computational Fluid Dynamics, Joseph Petersen

Electronic Theses and Dissertations

Computational fluid dynamics software was used to simulate the motion of circulating tumor cells in a variety of microfluidic cell isolation devices. Design of several novel microfluidic cell isolation devices was aided by viewing streamlines of fluid in devices in simulation. Devices that performed best in simulation used 5-micrometer wide guiding channels to guide cells to the capture location in the device. While these devices performed better than other devices in simulation and captured all particles regardless of position along inlet, experimental results differ from simulation.

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Nonlinear Stochastic Filtering For Online State Of Charge And Remaining Useful Life Estimation Of Lithium-Ion Battery, Suresh Daravath Jan 2018

Nonlinear Stochastic Filtering For Online State Of Charge And Remaining Useful Life Estimation Of Lithium-Ion Battery, Suresh Daravath

Electronic Theses and Dissertations

Battery state monitoring is one of the key techniques in Battery Management System (BMS). Accurate estimation can help to improve the system performance and to prolong the battery lifetime. The main challenges for the state online estimation of Li-ion batteries are the flat characteristic of open circuit voltage (OCV) with the function of the state of charge. Hence, the focus of this thesis study is to estimation of the state of charge (SOC) of Li-ion with high accuracy, more robustness. A 2nd order RC equivalent circuit model is adapted to battery model for simulation, mathematical model analysis, and dynamics characteristic …

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Evaluation Of The Mechanical Properties Of 3d Printed Carbon Fiber Composites, Max James Sauer Jan 2018

Evaluation Of The Mechanical Properties Of 3d Printed Carbon Fiber Composites, Max James Sauer

Electronic Theses and Dissertations

Studies have been done involving the use of carbon fiber as a reinforcement for three dimensional (3D) printed parts. The Markforged Mark Two is a commercial grade 3D printer capable of printing parts reinforced with continuous fibers such as carbon fiber, Kevlar, and fiberglass. Short Carbon Fiber Composite tensile specimen were printed on both a Markforged Mark Two and Flashforge Creator Pro using Markforged Onyx filament. The results of these parts were compared for their tensile properties, dimensional accuracy, and mass estimates. The Creator Pro was capable of producing stronger parts on average, while the Mark Two produced more dimensionally …

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Topology Optimization Of Lightweight Structural Composites Inspired By Cuttlefish Bone, Varun Kumar Gadipudi Jan 2018

Topology Optimization Of Lightweight Structural Composites Inspired By Cuttlefish Bone, Varun Kumar Gadipudi

Electronic Theses and Dissertations

Lightweight material structure is a crucial subject in product design. The lightweight material has high strength to weight proportion which turns into an immense fascination and a territory of investigation for the researchers as its application is wide and expanding consistently. Lightweight composite material design is accomplished by choice of the cellular structure and its optimization. Cellular structure is utilized as it has wide multifunctional properties with lightweight characteristics. Unless it has been topologically optimized, each part in a assembly most likely weighs more than it needs to. Additional weight implies abundance materials are being utilized, loads on moving parts …

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