Mechanical Engineering Commons^™

Generative Designs Of Lightweight Air-Cooled Heat Exchangers, Connor Miller

Mechanical Engineering Undergraduate Honors Theses

The development of high-performance air-cooled heat exchangers is required to permit the rapid growth of vehicle and aircraft electrification. In electric vehicles and airliners, the motors and power electronics are integrated into a compact space, leading to unprecedently high power density. To achieve higher overall thermal efficiency, the heat exchangers must be extremely light while maintaining their heat transfer performance and mechanical robustness. Recently advances in 3D metal printing, e.g., direct metal laser sintering, and selective laser melting, have enabled the manufacturing of high-performance robust heat exchangers by eliminating thermal boundary resistance and ensuring a uniform thermal expansion coefficient. Nonetheless, …

Autonomous Material Refill For Swarm 3d Printing, William C. Jones

Mechanical Engineering Undergraduate Honors Theses

3D printing currently offers robust and cheap rapid prototyping solutions. While standard 3D printing remains at the periphery of mass production, the technology serves as a starting point for the development of swarm manufacturing. Since swarm manufacturing is predicated upon autonomy, swarm technology companies such as AMBOTS are seeking to minimize human involvement in the swarm’s functions. At present, the 3D printing swarm consists of the printers, a transporter which can take them between job sites, and the floor tiles which provide power and support the build surfaces. To add to this ecosystem, this project is focused on the design …

Cal Poly Fluid Power Vehicle Challenge 2022, Sangmin Sung, Eddy Rodriguez, Travis Welch, Jeremy Baechler, Kevin Pauls

Mechanical Engineering

In this report, the Featherweight Cycles design team puts forth the scope and overview of their design project, discusses background research and competitor analysis, and presents the project’s final design and manufacturing plans. The overall goal of this project is to fabricate and compete in the Fluid Power Vehicle Challenge, hosted by the National Fluid Power Association. To better define the design process, the team researched previous year’s designs from Cal Poly, as well as winning designs from the last two years to form a baseline of knowledge about competing schools’ designs. After researching multiple design paths, Featherweight Cycles chose …

Ballasting System For An Autonomous Underwater Vehicle, Noura Rayes, Bahram Nassersharif, Zach Champney, Kyle Alessandro, Jason Mirandou

Senior Honors Projects

NOURA RAYES (Mechanical Engineering); Ballasting System for an Autonomous Underwater Vehicle Sponsor: Bahram Nassersharif (Mechanical Engineering)

Over the last year, our Mechanical Engineering Capstone team, Nautilus, has been working to design a ballasting system for various Autonomous Underwater Vehicles (AUVs) sponsored by Raytheon Technologies. Common AUV systems are used for a wide range of applications from environmental monitoring, oceanic exploration, to data collection. AUVs also have many technical advantages that make underwater tasks more efficient, cost-effective, and generally safer. Raytheon Technology, specifically, is looking to improve their existing ballasting mechanism for their AUVs to use for military defense. For this …

Ambient Temperature Phase Change Launcher, Johnny Molloy

Senior Honors Projects

JOHNNY MOLLOY (Mechanical Engineering) Ambient Temperature Phase Change Launcher Sponsor: Bahram Nassersharif (Mechanical Engineering)

Deployment of payloads stored in watertight cylindrical bodies in underwater environmental conditions are of interest to the marine and naval community. The proposed work will investigate the possibility of using inert carbon dioxide gas compressed into its liquid state and stored under pressure to launch payloads by means of expansion from a cylindrical tube. To suit the needs of the Naval Undersea Warfare Center (NUWC), this launching system must fire from up to 14 ft underwater, have two degrees of freedom, and the payload must not …

Cfd Simulation Of Varying Fuel Jet Placement Of Mach 2 Flow (Poster), Sara Broad

Honors Capstone Projects

No abstract provided.

Multistage Modeling Of Fatigue Of Ti-6al-4v Fabricated By Different Additive Manufacturing Techniques, Lionardo Lado, Saeed Ataollahi, Mohammad J. Mahtabi

Honors Theses

Thanks to its high strength-to-weight ratio and corrosion resistance, Ti-6Al-4V has gained a lot of attention in additive manufacturing (AM) of complex parts with aerospace and medical applications. The realistic loading condition in these applications is mostly cyclic. However, the main challenge with AM of this alloy - and in general AM of metallic parts - is fatigue resistance and durability of the part, which has been reported to be much lower than the conventional materials. In this study, fatigue life performance of three additive manufacturing methods was compared using the Multistage Fatigue model (MSF). MSF model predicts the fatigue …

On The Thermogravimetric Analysis Of Polymers: Polyethylene Oxide Powder And Nanofibers, Oriretan Omosola, Dorina M. Chipara, Mohammed Jasim Uddin, Karen Lozano, Mataz Alcoutlabi, Victoria Padilla-Gainza, Mircea Chipara

Mechanical Engineering Faculty Publications

Thermogravimetric analysis of polyethylene oxide (powder and nanofibers obtained by force spinning water or chloroform solutions of polyethylene oxide) was studied using different theoretical models such as Friedman and Flynn-Wall-Ozawa. A semiempirical approach for estimating the “sigmoid activation energy” from the thermal degradation was suggested and confirmed by the experimental data on PEO powder and nanofibers' mats. The equation allowed for calculating a “sigmoid activation energy” from a single thermogram using a single heating rate without requiring any model for the actual complex set of chemical reactions involved in the thermal degradation process. For PEO (powder and nanofibers obtained from …

Biofidelic Considerations For Improving Standardized Airflow And Firmness Testing For Infant Sleep Products, Wyatt D. Davis

Boise State University Theses and Dissertations

Background

Over the last 30 years, 83 infant fatalities (113 reported, 30 incidental) directly involving crib bumpers have been reported to the Consumer Product Safety Commission. Of these reports, 90% are for infants under a year old, with 61% occurring for infants between 1 and 4 months of age (Safety, 2020). There are currently a few regulations governing the design of crib bumper products, but none test the suffocation risk associated with these products using biofidelic methods.

Goals

We sought to explore the development of new testing methods that can determine the safety of different products and are physiologically representative …

Experimentation Of Abrasion Erosion At High Temperature For Concentrated Solar Power Systems, Tessa Mei-Lin Fong

Boise State University Theses and Dissertations

Concentrated solar power (CSP) is an alternative and sustainable way to produce energy. Studies have shown that running these plants at high temperatures above 700°C can increase the thermal efficiency in heat transfer. Molten salt is usually used as the heat transfer medium but cannot be used due to its low maximum temperature and high freezing point. Running these plants at high temperature brings up the concern of erosion and oxidation. Abrasion erosion occurs through the interaction of particles and material. The goal of this research is to understand material degradation due to abrasion erosion to understand the durability of …

Surface Laser Texturing Of Cocrmo Alloys, Gabriel Dharwadker

Biomedical Engineering Undergraduate Honors Theses

Artificial orthopedic implants such as hip joints suffer from excessive wear due to excess friction between the polyethylene and cobalt-chromium-molybdenum surfaces of the device. This increase in friction causes a fraction of them to give out within ten years. Therefore, to minimize the probability of this happening, recent research has been conducted regarding laser surface texturing of the cobalt-chromium-molybdenum alloy components of artificial joints. These surface textures serve to mimic the native lubrication mechanisms of cartilage in natural joints, which, in a natural joint, lowers the friction. However, the production of these laser surface textures is still a field of …

Triggering Thermal Runaway In Lithium-Ion Batteries, Chris John

Honors Scholar Theses

The proliferation of lithium-ion batteries enables electric devices such as cell phones to electric vehicles to become a reality. A latent danger, however, exists in these batteries. Mechanical, thermal, or electrical damage can initiate a phenomenon known as thermal runaway (TR). This damage causes internal short circuits within the battery, releasing heat and triggering exothermic decomposition reactions. The battery will catch fire if rapid cooling is not present. While experimental designs exist for evaluating TR, significant safety hazards and impracticality may impede testing efforts. Finite element analysis, therefore, becomes a vital tool in modeling TR and mitigation techniques. However, there …

Modelling And Development Of An Automated Ldpe Autoclave Reactor In Cfd For Revealing Ethylene Hot Spots, Eric Turman

Masters Theses

Computational Fluid Dynamics (CFD) was employed to develop a rigorous model of a low-density polyethylene (LDPE) autoclave reactor. Different numerical settings within the solver were evaluated to minimize false diffusion and to reflect the sensitive heat generation taking place during free radical polymerization. The rigorous CFD model employed reaction kinetics, Proportional Integral Derivative (PID) automated thermal management, and a rotating stirrer shaft. Validation was carried out to determine the sensitivity to time-step size, turbulence model, and grid resolution. Data were compared to an industrial scale plant autoclave to guide the development of CFD. Time-step independence was confirmed by comparing the …

Electrically Conductive Bearing Adapter Polymer Pad For Use In Freight Railcar Service Applications, Jesse M. Aguilera

Theses and Dissertations

Many freight railcars rest on polymer adapter pads made of injection-molded Thermoplastic Polyurethane (TPU) polymers which feature two copper studs to provide electrical conductivity through the adapter pads, which power onboard systems. In service, pads experience impact and cyclic loading, resulting in wear and plastic compression of the copper studs. This leads to signal interruptions and periodic replacement of the polymer pads, which results in downtime due to maintenance and reduced reliability since pad failure is unpredictable. These limitations in the current design are the impetus to create an electrically conductive polymer adapter pad that does not rely on the …

Machine Learning Based Aerodynamic Shape Optimization, Noe Martinez Jr.

Theses and Dissertations

The coefficient of pressure distribution for various 2D airfoil geometries were found using source – vortex panel methods. The data obtained in these simulations was used in multiple machine learning models which would predict the airfoil geometry from a given coefficient of pressure distribution. The neural networks employed were fully connected feedforward networks with Levenberg – Marquardt backpropagation and one model employed Bayesian Regularization. A novel tool for optimizing airfoil shape for a given coefficient of pressure distribution was created which performed well during testing. These models serve as the first step in minimizing the conflict between aerodynamic and stealth …

Self-Diverting Nanofluid In-Situ Gelled Acid For Matrix Acidizing Applications In Carbonate Formations, Javier Alejandro Perez

Theses and Dissertations

The main purpose of this project is to develop a nanofluid system that would help to divert the injected acid from the main flow regime into a relatively lower permeability zone and being able to dissolve the rock significantly. The system is meant to successfully create acidic gel in-situ after injecting the fluid in solution. It is expected that by altering either pH, temperature or amount of reactants, the viscosity of the fluid can be controlled so that the gel can be broken at a desired time.

An Experimentally Validated Finite Element Model Of Thermal Transient Response Of A Railroad Bearing Adapter, Javier E. Arroyo

Theses and Dissertations

Wayside hot box detectors (HBDs) are devices used to determine the health of railcar components such as bearings, axles, and brakes by monitoring the radiated temperature form these components. HBDs have been instrumental in reducing rail derailments in the decade, but the number of non-verified bearing removals has increased significantly. To combat these limitations, researchers have opted to use wireless onboard sensor devices directly mounted on the bearing adapter. The wireless onboard health monitoring system developed by the University Transportation Center for Railway Safety (UTCRS) utilizes temperature and vibration sensors to detect the condition of rolling stock. However, because the …

Cloth-Water Interaction For Air Humidification In Hdh Desalination, Alejandro Corona Martinez

Theses and Dissertations

The humidification-dehumidification (HDH) desalination technology is a promising desalination process that has the potential to provide cost-effective and environmentally friendly saltwater desalination, especially when combined with renewable energy sources. The working principle mimics the natural hydrologic cycle, involving the evaporation of seawater into water vapor (humidification) and condensation into freshwater (dehumidification). HDH desalination can be land-based or ocean-based. Some of the advantages of ocean-based systems include removing pretreatment processes, utilization of ocean energy (i.e. thermal and kinetic), and eliminating brine production. This study focuses on the design and experimental testing of a novel humidifier …

Machine Learning Tools In The Predictive Analysis Of Ercot Load Demand Data, Md Riyad Hossain

Theses and Dissertations

The electric load industry has seen a significant transformation over the last few decades, culminating in the establishment and implementation of electricity markets. This transition separates electric generation services into a distinct, more competitive sector of the industry, allowing for the introduction of greater unpredictability into the system. Forecasting power system load has developed into a core research area in power and energy demand engineering in order to maintain a constant balance between electricity supply and demand. The purpose of this thesis dissertation is to reduce power system uncertainty by improving forecasting accuracy through the use of sophisticated machine …

2022 (Spring) Ensi Informer Magazine, Morehead State University. Engineering Sciences Department

ENSI Informer Magazine Archive

The ENSI Informer Magazine published in the spring of 2022.

Mechanics Of Preimpregnated Fiber Tow Deposition And Compaction, Virginia Meredith Rauch

Mechanical & Aerospace Engineering Theses & Dissertations

In additive manufacturing, such as Automated Fiber Placement (AFP), defects often develop during the deposition and compaction of preimpregnated composite material, which reduce the strength of the resultant material. It is necessary to reduce defects and have good adhesion between plies to optimize the laminate performance and reduce delamination between composite layers. The aim of this work is to study the adhesion and deformation of preimpregnated (prepreg) composite material during the deposition and compaction stage in the composite forming process and how material parameters can be used to increase laminate strength. Two types of experimentation were performed on thermoset IM7/8552 …

Electromagnetic Modeling Of A Wind Tunnel Magnetic Suspension And Balance System, Desiree Driver

Mechanical & Aerospace Engineering Theses & Dissertations

Wind tunnels are used to study forces and moments acting on an aerodynamic body. While most results involve some interference from the mechanical supports used to hold the model, a Magnetic Suspension and Balance System (MSBS) is void of these interferences and presents an ideal test scenario. To further investigate the feasibility of dynamic stability testing at supersonic speeds using a MSBS, a preliminary design idea is currently being developed using an existing MSBS in a subsonic wind tunnel. This review focuses on the development of a mathematical model to more accurately portray the capabilities of the 6 inch Massachusetts …

Deep Learning Object-Based Detection Of Manufacturing Defects In X-Ray Inspection Imaging, Juan C. Parducci

Mechanical & Aerospace Engineering Theses & Dissertations

Current analysis of manufacturing defects in the production of rims and tires via x-ray inspection at an industry partner’s manufacturing plant requires that a quality control specialist visually inspect radiographic images for defects of varying sizes. For each sample, twelve radiographs are taken within 35 seconds. Some defects are very small in size and difficult to see (e.g., pinholes) whereas others are large and easily identifiable. Implementing this quality control practice across all products in its human-effort driven state is not feasible given the time constraint present for analysis.

This study aims to identify and develop an object detector capable …

Failure Mode, Effects And Criticality Analysis Of A Very Low Earth Orbit Cubesat Mission, Robb Christopher Borowicz

Mechanical & Aerospace Engineering Theses & Dissertations

When space programs launch vehicles into orbit, multiple failures could arise throughout the mission and corrective actions are often not an option. Applying reliability engineering approaches during the design phase focuses on analyzing risk by anticipating potential failures and mitigating uncertainties in the design. Old Dominion University, in partnership with the U.S. Coast Guard Academy, and the U.S. Air Force Institute of Technology designed and developed a 3U CubeSat mission to validate on-orbit, three space technology payloads. Mission SeaLion will fly as a secondary payload on stage two of Northrop Grumman’s Antares rocket and will be deployed in a very …

Investigating The Effects Of Topology On The Fracture And Failure Mechanisms Of Low Density Metamaterials, Kaitlynn Melissa Conway

All Dissertations

Advances in additive manufacturing have enabled the creation of low density metamaterials with fine features and complex topographies. These new metamaterial topologies and size scales not previously possible broaden the spectrum of lightweight materials with unique properties that are advantageous in a variety of applications. There however is a lack of understanding of metamaterial failure and fracture behaviors. Studies tend to report only a few material properties rather than a comprehensive description of behavior. Due to this, there is a hesitancy to incorporate metamaterials into engineering designs despite proven remarkable properties. This work seeks to investigate in three parts the …

Monitoring Of Tool Wear And Surface Roughness Using Anfis Method During Cnc Turning Of Cfrp Composite, Md Mofakkirul Islam

Theses and Dissertations

Carbon fiber-reinforced plastic (CFRP) is gaining wide acceptance in areas including sports, aerospace and automobile industry . Because of its superior mechanical qualities and lower weight than metals, it needs effective and efficient machining methods. In this study, the relationship between the cutting parameters (Speed, Feed, Depth of Cut) and response parameters (Vibration, Surface Finish, Cutting Force and Tool Wear) are investigated for CFRP composite. For machining of CFRP, CNC turning operation with coated carbide tool is used. An ANFIS model with two MISO system has been developed to predict the tool wear and surface finish. Speed, feed, depth of …

The Grate Solution: Simplifying Viking Oven Packaging Processes, Megan Jansen

Honors Theses

The following report details work completed to improve the Viking Oven Corporation’s gas oven assembly line. The current state of the line hosts an unreliable system for packaging oven grates. Viking manufactures two types of gas ovens on the same line: open burner and closed burner. These different types require different prepackaged grates to be included in the final assembly area. Viking estimates that the wrong grates are sent to the customer ten percent of the time. The following report presents research, brainstorming, problem-solving techniques, and proposed solutions to the problem. The proposed solution would solve the problem at little …

Investigating The Application Of Flettner Rotors On The Great Lakes, Garrett C. Bond

Senior Honors Theses

Climate change is quickly becoming one of the leading problems of the twenty-first century, and the maritime transportation sector is beginning to react. Wind propulsion technologies have been making a comeback led by the Flettner rotor. The deck-mounted, vertical, spinning cylinder generates a lift (or thrust) force perpendicular to the wind by utilizing the Magnus effect. Rotor performance has been studied extensively on many ocean shipping routes, but has not been on the Great Lakes, a region with a large maritime industry. This study aims to assess whether or not Flettner rotors are practical in the region by calculating propulsive …

Nanomechanical Characterization Of Vascular Tissue Using Atomic Force Microscopy, Ana Isabel Delgado Peralta

Theses and Dissertations

Cardiovascular morphogenesis and pathophysiology have been associated with the mechanical properties of the vessel wall. In this work, nanomechanical properties of diseased arteries and control groups were quantified using the Atomic Force Microscopy (AFM). Both tip sizes of 20nm and 5µm were used for examining the local and global stiffness. First, we measured the stiffness as a potential index factor of the mice’s aortic aneurysm. Results have shown the stiffness of mice aortic aneurysm is 58.84 ± 30.26 kPa, which is significantly different (P < 0.05) from the stiffness of the control group of 4.70 ± 17.41 kPa. This was attributed to the degradation of elastin fibers and increment of collagen deposition in the vessel as observed in the histological analysis. The lesion heterogeneity was illustrated by the stiffness gradient from 40 kPa to 1.2 MPa within a 2µm2 region. We also examined the stiffness of the diabetic rat aorta as a potential biomarker for disease progression. Results have shown a significantly higher stiffness of 70.25 ± 14.10 kPa in diabetic rat aorta, compared with 54.19 ± 14.15 kPa in the control group. Lastly, we characterized the human aortic calcifications to fill the knowledge gap of scarce datasets for calcification stiffness. Results have demonstrated the calcification stiffness as 61.5 ± 35 kPa, which is significantly larger than the stiffness of the control group of 12.0 ± 4.4 kPa. The stiffness variation was attributed to the percentage of calcium deposits, observed from the histological analysis. These nanomechanical characterizations could be further used for a better understanding of arterial adaptation and to provide insights for effective vascular therapies.

A Central Compact Hybrid-Variable Method With Spectral-Like Resolution, Md Mahmudul Hasan

Open Access Theses & Dissertations

Numerical methods for hyperbolic conservation laws have been a driving force for theresearch in scientific computing and simulation science in the past decades, as many physical, biological, and engineering systems are governed by these equations, such as fluid mechanics, tumor growth, and virtual wind tunnel simulations. Despite the existence of many schemes in the literature, people have never stopped searching for more accurate and efficient methods for these problems. Indeed, the increasing complexity of systems in emerging applications demands better resolution of sub-grid scale phenomenon whereas classical methods usually fail to deliver high-fidelity simulation results of such systems within realistic …