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2019

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Mechanical Engineering

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Full-Text Articles in Engineering

Modeling, Simulation, And Validation Of Process-Structure-Property Relationships In Fused Filament Fabrication, Aaron Grant Dec 2019

Modeling, Simulation, And Validation Of Process-Structure-Property Relationships In Fused Filament Fabrication, Aaron Grant

Electronic Theses and Dissertations

As additive manufacturing (AM) grows in popularity, the need for better simulation tools to predict the process-structure-property relationships of AM parts becomes ever more necessary to employ the technology in design of functional parts with varying degrees of complexity and performance requirements. Many simulation tools and techniques have been developed that aim to achieve this goal, and the main purpose of this research is to explore how well different simulation tools and modeling approaches can capture various AM-specific features such as inter-raster and end-of raster voids, and residual stresses induced by dissimilar rates of thermal expansion. Process simulation of fused ...


Failure Of High Strength Concrete Under Dynamic Uniaxial Compression, Colin Loeffler Dec 2019

Failure Of High Strength Concrete Under Dynamic Uniaxial Compression, Colin Loeffler

Mechanical Engineering Research Theses and Dissertations

The failure strength of concrete materials has been widely shown to be dependent on experimental parameters such as specimen geometry and strain-rate. The effects of specimen geometry have been shown both theoretically and experimentally to be a result of the quasi-brittle nature of concrete. While the failure strength of concrete has been widely reported to increase significantly when deformed at high strain-rates, the physical mechanisms driving this phenomenon remain the source of debate amongst researchers. This means that constitutive models designed to predict this rate dependent behavior are not based on the real physical mechanisms that drive this behavior but ...


Acoustic Design Optimization With Isogeometric Analysis And Differential Evolution, Garrett W. Dodgen Dec 2019

Acoustic Design Optimization With Isogeometric Analysis And Differential Evolution, Garrett W. Dodgen

Mechanical Engineering Theses

The objective of this study is to utilize shape optimization to enhance the performance of devices relying on acoustic wave propagation. Particularly, the shape of a horn speaker and an acoustic energy harvester were optimized to enhance their performance at targeted frequencies. High order Isogeometric Analysis (IGA) was performed to estimate the acoustic pressure with minimum geometry and pollution errors [1]. The analysis platform was then combined with Differential Evolution (DE) to optimize the geometry of the horn speaker and energy harvester at a given frequency. These cases effectively demonstrate two applications of Isogeomtric shape optimization for devices relying on ...


Biomechanical Analysis Of Open-Skull High-Rate Traumatic Brain Injury Using Finite Element Mouse Brain Model, Lihong Lu Dec 2019

Biomechanical Analysis Of Open-Skull High-Rate Traumatic Brain Injury Using Finite Element Mouse Brain Model, Lihong Lu

Electronic Thesis and Dissertation Repository

To better understand traumatic brain injury (TBI), it is necessary to correlate with injuries, which are observed from in vivo laboratory experiments, to brain mechanical responses, which can so far be best predicted by finite element (FE) models. Firstly, a previously validated FE model was improved to investigate the effect of repeated impacts and lateral movements on brain responses to ensure the accuracy and reproducibility of controlled cortical impact (CCI) across different labs. Then, a new FE mouse brain model with the detailed three-dimensional (3D), non-linear vasculature was developed to study how the vasculature affected brain response in CCI and ...


Ambient Temperature Dependence Of Air-Cooled Condenser Performance And Parameters, Alexander Darr Smith Dec 2019

Ambient Temperature Dependence Of Air-Cooled Condenser Performance And Parameters, Alexander Darr Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Thermoelectric power generation uses 38% of total fresh water withdrawals and majority of that water is used during steam condensation. Air-cooled condensers are an alternative to water-cooled condensers for power generation. Ambient air temperature affects the performance of air-cooled condensers. A small air-cooled condenser was run under the ambient air temperature extremes of Las Vegas in order to examine the system performance and air-side heat transfer parameters. Three different sets of tubes with different surface areas and geometries were studied. The condenser is equipped with several air velocity sensors, thermocouples and thermistors to measure the conditions to develop the air-side ...


Development Of High-Speed Photoacoustic Imaging Technology And Its Applications In Biomedical Research, Yun He Dec 2019

Development Of High-Speed Photoacoustic Imaging Technology And Its Applications In Biomedical Research, Yun He

Engineering and Applied Science Theses & Dissertations

Photoacoustic (PA) tomography (PAT) is a novel imaging modality that combines the fine lateral resolution from optical imaging and the deep penetration from ultrasonic imaging, and provides rich optical-absorption–based images. PAT has been widely used in extracting structural and functional information from both ex vivo tissue samples to in vivo animals and humans with different length scales by imaging various endogenous and exogenous contrasts at the ultraviolet to infrared spectrum. For example, hemoglobin in red blood cells is of particular interest in PAT since it is one of the dominant absorbers in tissue at the visible wavelength.The main ...


Cfd Simulation Investigating The Effects Of Groove Geometry On Heat Transfer For Internally Grooved Tubes, Richard Zaven Saroukhanoff Dec 2019

Cfd Simulation Investigating The Effects Of Groove Geometry On Heat Transfer For Internally Grooved Tubes, Richard Zaven Saroukhanoff

UNLV Theses, Dissertations, Professional Papers, and Capstones

This numerical study investigates the thermal performance of internally grooved tubes used in heat exchangers. In order to enhance the performance of heat exchangers, turbulence promoters are inserted along the streamwise flow. The use of inserts, grooves, and augmentations along the axial length of the tube creates disturbances that improve the overall heat transfer due to enhanced fluid mixing and greater surface contact boundary walls. However, the implementation of tube wall augmentations creates an increase in pressure drop across the tube which must be compensated for with additional pumping power for the working fluid. Therefore, in order to analyze the ...


Integrated Design Approach For Coronary Stents Using Flexinol Shape Memory Alloy, Matthew Lucci Dec 2019

Integrated Design Approach For Coronary Stents Using Flexinol Shape Memory Alloy, Matthew Lucci

Mechanical Engineering Theses

This research seeks to develop and verify a model for control of the shape memory alloy (SMA) Flexinol and apply such findings to practical application of the material as a platform for bare metal stenting technologies. Utilizing experimental data and material properties, a mathematical model of the thermoelectric contraction behavior of Flexinol wire samples was developed. This model accounted for variable resistance due to the shape memory effect of the Flexinol wire as it experiences a crystalline phase change. It also accounted for the change in the cross-sectional area of the wire as the wire experienced thermal expansion and contraction ...


Energy Modelling To Evaluate The Thermal Regulation Of Aquaculture Raceways Using Geothermal Heat Exchange, Mitchell H. Kuska Dec 2019

Energy Modelling To Evaluate The Thermal Regulation Of Aquaculture Raceways Using Geothermal Heat Exchange, Mitchell H. Kuska

Electronic Thesis and Dissertation Repository

Raceways are used in the aquaculture industry to farm fish species that swim against an upstream current. Raceways often draw water from a large waterbody and hence, their temperature changes due to seasonal variation, which directly affect the production yield. This study investigates a novel approach to regulate the raceway water temperature in a sustainable way by utilizing geothermal energy exchange. Energy models were developed to simulate heat transfer in a geothermal borehole heat exchange system and in the raceway system. The two models were then coupled to simulate the thermal regulation of the raceway water via borehole heat exchangers ...


Numerical And Semi-Analytical Estimation Of Convective Heat Transfer Coefficient For Buildings In An Urban-Like Setting, Anwar Demsis Awol Dec 2019

Numerical And Semi-Analytical Estimation Of Convective Heat Transfer Coefficient For Buildings In An Urban-Like Setting, Anwar Demsis Awol

Electronic Thesis and Dissertation Repository

Urban building arrangements such as packing density, orientation and size are known to influence the microclimate surrounding each building. Studies on the impact of urban microclimatic changes on convective heat transfer coefficient (CHTC) from a stock of buildings, however, have been rare in surveyed literature. The present study focuses on numerical and analytical investigation of CHTC from building-like models with homogeneous set of equal and unequal planar and frontal densities. Consequently, the study discusses the CHTC response in relation to broader changes in the urban surface form. Part of the process involves the development of a simplified one-dimensional semi-analytical CHTC ...


A Wearable Mechatronic Device For Hand Tremor Monitoring And Suppression: Development And Evaluation, Yue Zhou Dec 2019

A Wearable Mechatronic Device For Hand Tremor Monitoring And Suppression: Development And Evaluation, Yue Zhou

Electronic Thesis and Dissertation Repository

Tremor, one of the most disabling symptoms of Parkinson's disease (PD), significantly affects the quality of life of the individuals who suffer from it. These people live with difficulties with fine motor tasks, such as eating and writing, and suffer from social embarrassment. Traditional medicines are often ineffective, and surgery is highly invasive and risky. The emergence of wearable technology facilitates an externally worn mechatronic tremor suppression device as a potential alternative approach for tremor management. However, no device has been developed for the suppression of finger tremor that has been validated on a human.

It has been reported ...


Passive Separation Of Binary Fluid Mixtures In Microchannels Using Lattice Boltzmann Method, Mohanad Kamil Radhi Dec 2019

Passive Separation Of Binary Fluid Mixtures In Microchannels Using Lattice Boltzmann Method, Mohanad Kamil Radhi

Dissertations and Theses

Fluid mixtures in real life exist in two forms: miscible and immiscible. Separation of these mixtures using chemical agents or thermal energy has both environmental and economic disadvantages. The high cost and the environmental damage caused by the traditional separation techniques have stimulated both academia and industry to seek alternatives. The emergence of microfluidics offers robust solutions for a broad span of transport problems due to the high surface to volume ratio and reduced length scales. Particularly, the separation efficiency increases significantly due to the aforementioned feature. However, there is still a pressing need of passive separations for the sake ...


Lightweight Racing Suspension, Colin Haynes Dec 2019

Lightweight Racing Suspension, Colin Haynes

Honors Theses

The purpose of this senior design project is to design and optimize the new suspension system for Western Michigan University’s 2020 solar car. The current solar car was 43% heavier than the average solar car, and was the heaviest single occupant vehicle competing in the American Solar Challenge. The scope of the project is to reduce the weight as much as possible from the old 2016 suspension. The new suspension weighed 34.91 lbs less than the 2016 suspension system while maintaining a minimum factor of safety greater than 1.5, compliant with American Solar Challenge regulations. The design ...


Axial Compressor Based On Plastic Additive Manufacturing, Chris Phu Dec 2019

Axial Compressor Based On Plastic Additive Manufacturing, Chris Phu

Mechanical Engineering Undergraduate Honors Theses

Turbomolecular pumps designed to function in very low pressures tend to be too prohibitively expensive for student researchers. On the other hand, while conventional pumps are affordable, they can’t function in extreme low pressures. An additively manufactured axial compressor however is inexpensive to manufacturer and only needs to be build up enough pressure for a conventional pump to function. After many design iterations, a final iteration that is near vacuum chamber ready has been 3D printed and tested for spin functionally. The designed axial compressor is easy to assemble and very modular. Conclusions from each of the design iterations ...


Development And Characterization Of A Biopolymer Direct-Write Process For 3d Microvascular Structures Formation., Xiaoming Fan Dec 2019

Development And Characterization Of A Biopolymer Direct-Write Process For 3d Microvascular Structures Formation., Xiaoming Fan

Electronic Theses and Dissertations

Engineering of bulk tissues has been limited by the lack of nutrient and waste exchange in these tissues without an adjacent capillary network. To produce microvasculature, a scaffold must be produced that provides temporary mechanical support and stimulate endothelial cell adhesion, growth, and morphogenesis into a vessel. However, current well-established techniques for producing microvasculature, such as electrospinning, are limited since they lack both the precision to control fiber placement in three-dimensional space and the ability to create fiber networks with predefined diameters to replicate the physiological microvascular progression from arteriole to capillary to venule. Our group has developed a “Direct-write ...


Thermoresponsive Switchable Solvents For Enhanced, Simultaneous Microalgae Oil Extraction Reaction For Biodiesel Production, Mukhtar Ahmed Ismail Dec 2019

Thermoresponsive Switchable Solvents For Enhanced, Simultaneous Microalgae Oil Extraction Reaction For Biodiesel Production, Mukhtar Ahmed Ismail

Mechanical Engineering Theses

In this study, a thermo-responsive switchable solvent (TSS), with a tunable hydrophobicity by simply changing the temperature (between 25 to 45oC) was used for simultaneous lipids extraction from wet microalgae and biodiesel production. By manipulating the hydrophobicity of the solvent, the cell wall disruption, lipid extraction and transesterification, and product separation steps were all carried out in a single pot, while eliminating the need for the energy intensive and time-consuming drying step. To overcome the problems currently encountered by using conventional alkaline catalysts in the transesterification of lipids, immobilized enzyme has been used. The proposed TSS consisted of an ionic ...


Automation Of Data Analysis In Formula 1, Adam Joseph Mourad, Prescott Jeanne Delzell, Patrick Conner Mccabe Dec 2019

Automation Of Data Analysis In Formula 1, Adam Joseph Mourad, Prescott Jeanne Delzell, Patrick Conner Mccabe

Industrial and Manufacturing Engineering

This paper explores economic solutions for Formula 1 racing companies who are interested in data visualization tools. The research was conducted on the current development of data gathering, data visualization, and data interpretation in Formula 1 racing. It was found that a large chunk of racing companies within the league needs an affordable, effective, and automated visualization tool for data interpretation. As data collection in Formula 1 arises, the need for faster and more powerful software increases. Racing companies profit off-brand exposure and the more a racing team wins, the more exposure they receive. The goal of the paper focuses ...


Process Improvement And Lift Design For The Installation Of A Metrology Machine Assembly, Dalt J. Lasell, James Mitchell O'Meara, Matthew Steensma Dec 2019

Process Improvement And Lift Design For The Installation Of A Metrology Machine Assembly, Dalt J. Lasell, James Mitchell O'Meara, Matthew Steensma

Industrial and Manufacturing Engineering

The objective is to work with Onto Innovations, a leading provider of semiconductor metrology and manufacturing solutions, to develop a system that safely installs a 250lb optics plate into the Atlas III: one of their metrology machines. Based in Milpitas, CA, Onto Innovations utilizes a variety of operations to create different products and assembles each product on site. The 250lb optics plates are WIP that are transferred between fixtures and the Atlas III using a combination of lifts and human workers. The WIP have long lead times, high tolerances, and large costs associated with their manufacturing process.

Onto Innovations identified ...


Critical Radius Of Insulation, Maria N. Ambrose, Samuel J. Sayre, Travis W. Martin, Matt T. Sterling Dec 2019

Critical Radius Of Insulation, Maria N. Ambrose, Samuel J. Sayre, Travis W. Martin, Matt T. Sterling

Mechanical Engineering

The critical radius of insulation is a counterintuitive concept within the study of heat transfer. The theory states that adding insulation to a cylindrical or spherical object will increase the rate of heat loss rather than decrease it, if the radius (thickness) of the insulation is at its “critical” value. The Critical Radius of Insulation Senior Project is designed to demonstrate this phenomenon to Heat Transfer students via a portable apparatus. The concept will be demonstrated with a cylindrical object which is heated by way of a separate voltage source. Thermocouples will display the temperature of the cylinder while insulation ...


Fiberglass Mat-Roll Carryover, Bryce Youngson, Aaliyah Ramos, Johann Cayaban, Tony Ledesma Dec 2019

Fiberglass Mat-Roll Carryover, Bryce Youngson, Aaliyah Ramos, Johann Cayaban, Tony Ledesma

Mechanical Engineering

The asphalt shingle is a type of roof shingle that uses asphalt for waterproofing. Its low cost and easy installation make it one of the most common roof covers in North America. General Aniline and Film (GAF) is one of the nation’s largest manufacturers of roofing materials and produces asphalt shingles at their Shafter, California manufacturing facility. To manufacture asphalt shingles, a base material of fiberglass passes through a series of processes that sequentially add asphalt, ceramic-coated mineral granules, and thermoplastic adhesive. The fiberglass base-material arrives at the manufacturing facility in large rolls that workers must periodically splice together ...


Model Block Press Design, Ben Todd Van Hamersveld, Chester Wong, Alexander Wing-Jon Giannousis Dec 2019

Model Block Press Design, Ben Todd Van Hamersveld, Chester Wong, Alexander Wing-Jon Giannousis

Mechanical Engineering

This project’s goal is to redesign the Center for Vocational Building Technology (CVBT) BP9 earth block press, which makes 1/3 scale compressed earth blocks to build demonstration model homes in Thailand. The full-scale block press, the BP6, provides a sustainable and affordable technique for constructing habitable homes in Thailand. The BP9 serves as a tool to inform the public of the advantages of human-powered earth block presses through demonstration. The BP9 press design has multiple problems: it is too expensive to manufacture, there is too much friction when used, it has several weak points due to users unintentionally ...


Deployable Cover For Cubesat Fuv Imager, Edwin J. Rainville, Patrick J. Rainville, Jeff Wagner Dec 2019

Deployable Cover For Cubesat Fuv Imager, Edwin J. Rainville, Patrick J. Rainville, Jeff Wagner

Mechanical Engineering

The goal is to develop a deployable cover for a far ultraviolet imager cube satellite that will be used to map the earth’s auroras in the ionosphere. The deployable cover is used to protect the Far Ultra-Violet (FUV) sensor and lenses, house two mirrors which are used to filter unwanted light and expose optics when deployed. The deployable cover consists of a door, an actuator, a lockout mechanism, and an “open position” indicator. This project also includes designing a fixture for testing the optical alignment of the deployable cover after launch and during orbital conditions. The subassembly is required ...


Waste Gasification, Glyn D. Lewis, Nash Taylor, Nicholas L. Ordonez, David S. Mccallum Dec 2019

Waste Gasification, Glyn D. Lewis, Nash Taylor, Nicholas L. Ordonez, David S. Mccallum

Mechanical Engineering

This document summarizes the work the IGT Team has conducted on the topic of waste to energy gasification over the Cal Poly Winter, Spring, and Fall quarters of 2019. The project is being carried out by four Cal Poly Mechanical Engineering students: Nash Taylor, Glyn Lewis, David McCallum, and Nicholas Ordonez and the sponsor of this project is Tod duBois. The team’s original goal was to successfully create a system that compiles residential solid waste on a small scale, gasifies it, and measures the typical syngas outputs, so that the team may assess the viability of gasification of household ...


Katie's Jogger, Megan Guillermo, Erin Wint, Abdullah Sulaiman, Kathryn Mangiaracina Dec 2019

Katie's Jogger, Megan Guillermo, Erin Wint, Abdullah Sulaiman, Kathryn Mangiaracina

Mechanical Engineering

Edward Robinson is an avid runner who would like to take his daughter on runs. His daughter, Katie, is 100% wheelchair bound and currently does not fit in any commercial joggers on the market. The project team was expected to design, build, and test a custom working prototype of a jogger that the sponsor can use to take his daughter on runs. This entire project was performed over a span of three quarters.


2-Axis Electric Off-Road Bucket Seat Bases, Brennan K. Slater, Alexander P. Croteau, Spencer M. Kubik Dec 2019

2-Axis Electric Off-Road Bucket Seat Bases, Brennan K. Slater, Alexander P. Croteau, Spencer M. Kubik

Mechanical Engineering

Off-road vehicle bucket seats are currently restricted to a single position relative to the floor of the vehicle. Drivers and riders desire the ability to adjust their seat position to increase comfort and allow for a greater size range of riders to fit safely within the cabin or roll cage. To develop a viable solution, the team has gone through an extensive design process and has constructed a functioning prototype. This Final Design Report encapsulates the entire design process and concludes with recommendations for changes we would make looking both back in review as well as moving forward with further ...


Mad Jack Alpine Touring Model Design, Austin Gasbarra, Gillian Stargensky, Madeleine Mccool, Brannon Smudz Dec 2019

Mad Jack Alpine Touring Model Design, Austin Gasbarra, Gillian Stargensky, Madeleine Mccool, Brannon Smudz

Mechanical Engineering

Skiing is a sport enjoyed by millions of people every year, yet ski boots are very uncomfortable and cost- prohibitive, resulting in a low conversion rate of first-time skiers to lifetime skiers. Additionally, Alpine Touring (AT) is seeing a surge in popularity as ski resorts become more expensive, but few companies are developing affordable products in this realm. Mad Jack Snow Sports has developed a product that they believe addresses some of the main issues associated with skiing, but they want to develop their product line further. The problem statement and scope state that the purpose of this project is ...


Mechanized Advent Calendar, Oma Skyrus, Sigrid Derickson, Tyler Koski, Daniel Clifton Dec 2019

Mechanized Advent Calendar, Oma Skyrus, Sigrid Derickson, Tyler Koski, Daniel Clifton

Mechanical Engineering

Within this document, the “Naughty and Nice” team will describe the details associated with the completion of this project, which involves creating an animated advent calendar for the Cambria Christmas Market. The problem, the customers and stakeholders, and the general goals of the project are introduced. The team conducted background research; how this research helps in finding a solution or supporting the needs of the sponsor is illustrated. Initial research includes interviews with the sponsor and potential users, patent and existing product searches, and some technical research pertaining to the subject. The team found that there are not many existing ...


Damage Resistance And Tolerance Of 3d Woven Composites, Justin T. Mcdermott Dec 2019

Damage Resistance And Tolerance Of 3d Woven Composites, Justin T. Mcdermott

Electronic Theses and Dissertations

Composite materials have been adopted into primary aircraft structures by virtue of their great strength-to-weight and stiffness-to-weight ratios, fatigue insensitivity, and corrosion resistance. These characteristics are leveraged by aircraft designers to deliver improved fuel effciency and reduced scheduled maintenance burdens for their customers. These benefits have been impressively realized in the Boeing 787 and Airbus A350 XWB, with airframes utilizing about 50% composites by weight. Tempering these successes, however, are the inherent vulnerabilities of carbon-fiber reinforced composites. When compared to conventional metallic structure, composite laminates are more sensitive to stress concentrations at mechanical fastenings and damage due to low-velocity impact ...


The High Rise Storage System, Justin H. Harmon Dec 2019

The High Rise Storage System, Justin H. Harmon

Chancellor’s Honors Program Projects

No abstract provided.


Gearbox Baffle Optimization, Arduin Dec 2019

Gearbox Baffle Optimization, Arduin

Master's Theses

Current literature reveals there is limited consensus on the placement of baffles within a gearbox to reduce churning losses. Thus, there is a need for a process to identify baffle clearances that result in maximum and minimum churning losses. There are two types of baffles: axial and radial. While both axial and radial baffles cause reductions in churning losses to various degrees, the focus is on the effect of radial baffles. The effect of a board (rectangular plate) baffle location on the churning losses of a single gear gearbox are evaluated using computational fluid dynamics (CFD) implemented in Ansys. Several ...