Mechanical Engineering Commons^™

A Study Of Several Applications Of Parallel Computing In The Sciences Using Petsc, Nicholas Stegmeier

Electronic Theses and Dissertations

The importance of computing in the natural sciences continues to grow as scientists strive to analyze complex phenomena. The dynamics of turbulence, astrophysics simulations, and climate change are just a few examples where computing is critical. These problems are computationally intractable on all computing platforms except supercomputers, necessitating the continued development of efficient algorithms and methodologies in parallel computing. This thesis investigates the use of parallel computing and mathematical modeling in the natural sciences through several applications, namely computational fluid dynamics for impinging jets in mechanical engineering, simulation of biofilms in an aqueous environment in mathematical biology, and the solution …

Quantifying The Performance Of The Protodune Single Phase Neutrino Detector Using Computational Fluid Dynamics, Dillon Pedersen

Electronic Theses and Dissertations

The goal of this research is to provide scientifically-valid computationally generated data of the flow, thermal, and impurity data of the ProtoDUNE single phase detector. Results are compared and validated against an actual detector that is currently being utilized to collect temperature and impurity data. This research will investigate the flows inside these detection chambers using computational fluid dynamics to find approximate solutions to the governing equations of fluid mechanics. Impurity and flow data will allow researchers to determine if results collected are being obstructed by high levels of impurity. Novel approaches have been developed to strike a balance between …

The Effects Of 3d Printing Parameters And Surface Treatments On Convective Heat Transfer Performance, Lucas N. Pereira

Electronic Theses and Dissertations

Additive manufacturing technology and applications have quickly expanded in many industries over the last five years. As additive manufacturing is studied and refined, improvements in resolution and strength have helped propel further growth of the industry. This study focuses on an additive manufacturing technology called fused filament fabrication (FFF). FFF involves the extrusion and layer-by-layer deposition of a molten thermoplastic material to create the desired part. One potential new application of fused filament fabrication is the manufacture of heat exchangers and heat sinks. This study focuses on developing baseline experimental data related to convective heat transfer coefficients over surfaces of …

Mechanical Properties Of 3d Printed Acrylonitrile Styrene Acrylate, William Cahyadi

Electronic Theses and Dissertations

Several studies have been conducted on FDM 3d printed materials such as PLA (Polylactic Acid) and ABS (Acrylonitrile Butadiene Styrene), however, not for ASA (Acrylonitrile Styrene Acrylate). The use of ASA has been increasing due to its resistance to UV, heat, and some chemicals. The resistance to UV prevents the material from degrading its material properties in common outdoor conditions, whereas resistance to heat and oil prevents the material from discoloration. This combination of effects allows designers to use ASA in outdoor applications, however, material properties for ASA in the FDM 3d printing manufacturing process are not well defined. It …

Determine Airborne Release Fractions (Arf) / Respirable Fractions (Rf) For Use In Safety Based Documents, Michael Quinn, Jacob Miller

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Atomistic Simulations Of Nanoindentation Response Of Irradiation Defects In Iron, M. Mustafa Azeem, Qingyu Wang, Muhammad Zubair

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Radiation response of a material is a consequence of defects' evolution in any radiation damage event. The radiation-induced defects can significantly alter the mechanical properties of a material. Radiation damage initiates from incident neutron by bombardment on solid material causing production and evolution of Frenkel defects. Since voids are formed due to aggregation of a large number of vacancies that cause dimensional changes and hence irradiation-induced swelling. In order to characterize the effect of irradiation defects, we have performed molecular dynamics (MD) simulations to investigate nanoindentation response of point defects and voids in Fe and their effects on mechanical parameters. …

Resistance To Helium Bubble Formation In Amorphous Sioc/Crystalline Fe Nanocomposite, Qing Su, Tianyao Wang, Jonathan Gigax, Lin Shao, Michael Nastasi

Department of Mechanical and Materials Engineering: Faculty Publications

The management of radiation defects and insoluble He atoms represent key challenges for structural materials in existing fission reactors and advanced reactor systems. To examine how crystalline/amorphous interface, together with the amorphous constituents affects radiation tolerance and He management, we studied helium bubble formation in helium ion implanted amorphous silicon oxycarbide (SiOC) and crystalline Fe composites by transmission electron microscopy (TEM). The SiOC/Fe composites were grown via magnetron sputtering with controlled length scale on a surface oxidized Si (100) substrate. These composites were subjected to 50 keV He+ implantation with ion doses chosen to produce a 5 at% peak He …

Fast Growth Of Thin Mapbi3 Crystal Wafers On Aqueous Solution Surface For Efficient Lateral-Structure Perovskite Solar Cells, Ye Liu, Qingfeng Dong, Yanjun Fang, Yuze Lin, Yehao Deng, Jinsong Huang

Department of Mechanical and Materials Engineering: Faculty Publications

Solar-grade single or multiple crystalline wafers are needed in large quantities in the solar cell industry, and are generally formed by a top-down process from crystal ingots, which causes a significant waste of materials and energy during slicing, polishing, and other processing. Here, a bottom-up technique that allows the growth of wafer-size hybrid perovskite multiple crystals directly from aqueous solution is reported. Single-crystalline hybrid perovskite wafers with centimeter size are grown at the top surface of a perovskite precursor solution. As well as saving raw materials, this method provides unprecedented advantages such as easily tunable thickness and rapid growth of …

An Analysis Of Resistance Spot Weld Quality Based On Acoustic And Electrical Signatures, Ivan Charles Butler

Theses and Dissertations--Manufacturing Systems Engineering

The union of a set of materials by way of Resistance Spot Welding is designed so that once fused together, a substantial amount of intentional, external force must be applied to separate the contents. Therefore, Resistance Spot Welding is often the preferred fusion method in high-volume manufacturing processes. The result of Resistance Spot Welding however is the formation of a weld nugget which is not visible to the naked eye. Destructive and/or ultrasonic methods applied off-line must be used to determine the quality of each weld; both inefficient and expensive processes. The following research analyzes the data fed back during …

Implementation And Analysis Of True Lean In A Startup Company By Using Pdca Model, A Case Study In A Manufacturing Venture, Ankit Jangid

Theses and Dissertations--Manufacturing Systems Engineering

The purpose of this research is to implement and analyze the true lean transformation in a manufacturing start-up organization. Often, lean transformations are observed in developed manufacturing organizations having sophisticated production lines and numerous employees, where lean tools are utilized to reduce waste while increasing profit. However, this type of transformation is narrowly focused on quantifiable process results and falls short of the ultimate goal, establishing a true lean culture within the organization. As a result, it is recommended that true lean principles, philosophies, culture, operations environment and tools be applied at the very beginning stages of an organization, or …

Investigation Of Chip-Form And Tool-Wear In Turning Of Hardened Af9628 Alloy Under Various Cooling And Lubrication Conditions, Jason Wolf

Theses and Dissertations--Manufacturing Systems Engineering

Next generation defense and commercial applications for structural steels require new alloys that eliminate or reduce critical elements from their composition to lower cost and improve manufacturability, while maintaining or exceeding high strength and toughness requirements. A new alloy, denoted as AF9628, has recently been developed for this purpose and its manufacturing characteristics and the material response in component manufacturing must be fully understood.

In the present study, hardened AF9628 alloy was turned with a coated carbide cutting tool under fixed cutting speed, feed rate, and depth of cut parameters. This work focuses on chip-form and tool-wear analysis to understand, …

Human Gait Analysis Metric For Gait Retraining, Tyagi Ramakrishnan, Seok Hun Kim, Kyle B. Reed

Mechanical Engineering Faculty Publications

The combined gait asymmetry metric (CGAM) provides a method to synthesize human gait motion. The metric is weighted to balance each parameter’s effect by normalizing the data so all parameters are more equally weighted. It is designed to combine spatial, temporal, kinematic, and kinetic gait parameter asymmetries. It can also combine subsets of the different gait parameters to provide a more thorough analysis. The single number quantifying gait could assist robotic rehabilitation methods to optimize the resulting gait patterns. CGAM will help define quantitative thresholds for achievable balanced overall gait asymmetry. The study presented here compares the combined gait parameters …

Decentralized Hamiltonian Control Of Multi-Der Isolated Microgrids With Meshed Topology, Mohamed Toub, Rush Robinett, Mohamed Maaroufi, Ghassane Aniba

Michigan Tech Publications, Part 1

The new electricity grid of the future, smart grid, can be seen as the interconnection of multiple microgrids. These microgrids are usually composed of distributed energy resources (DERs) that connect to each other in different topologies. Therefore, the modeling and control of meshed microgrids are requisite. This paper presents a mathematical approach for the modeling and decentralized control of multi-DER isolated microgrids (ImGs) with a meshed topology. Based on the advanced control scheme: Hamiltonian surface shaping and power flow control (HSSPFC), decentralized controllers are designed independently using only local information. These controllers regulate the voltage at the point of common …

Étude Exploratoire Sur Les Pratiques Des Fabricants De Machines Au Québec En Lien Avec L’Intégration De La Sécurité Des Machines Dès Leur Conception, Yuvin Chinniah, François Gauthier, George Abdul-Nour, Sabrina Jocelyn, Barthélemy Aucourt, Guy Bordeleau

Rapports de recherche scientifique

Le présent rapport est destiné principalement à tout organisme québécois œuvrant en matière de prévention des lésions professionnelles (ex. : la Commission des normes, de l’équité, de la santé et de la sécurité du travail (CNESST), les associations sectorielles paritaires (ASP)), pour un ou plusieurs secteurs industriels donnés. Il porte sur une étude exploratoire concernant l’intégration de la sécurité dès la conception des machines et qui a été réalisée auprès de fabricants. Ce rapport intéressera également les concepteurs et fabricants désireux de se renseigner sur la manière dont la sécurité est prise en compte dans la mise en œuvre de …

Machine Vision Integrated Three-Dimensional Printing System, Chaiwuth Sithiwichankit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Three-dimensional printing has been a widespread solution of fabricating geometrical customized products. Any 3D printed product is normally fabricated at a position defined with respect to the coordinate system of the corresponding 3D printer. So, the 3D printing cannot be conveniently implemented in some fabricating applications in which fabricating positions are commonly constrained to some physical references, e.g., architecture construction, surface restoration, food decoration, etc. This research aimed to integrate the 3D printing with machine vision, which is vastly used for guiding robotic systems to operate at desirable positions constrained to physical objects. Hence, the 3D printing can be conveniently …

Capillary Forces In Partially Saturated Thin Fibrous Media, Ali Moghadam

Theses and Dissertations

Capillarity is often exploited in self-cleaning, drag reducing and fluid absorption/storage (sanitary products) purposes just to name a few. Formulating the underlying physics of capillarity helps future design and development of optimized structures. This work reports on developing computational models to quantify the capillary pressure and capillary forces on the fibrous surfaces. To this end, the current study utilizes a novel mass-spring-damper approach to incorporate the mechanical properties of the fibers in generating virtual fibrous structures that can best represent fibrous membranes. Such virtual fibrous structures are then subjected to a pressure estimation model, developed for the first time in …

Investigation Of Void Formation In Friction Stir Welding Of 7n01 Aluminum Alloy, Xingxin Zhao, Jianmin Han, Joseph P. Domblesky, Zhiyong Yang, Zhiqiang Li, Xiaolong Liu

Mechanical Engineering Faculty Research and Publications

Friction Stir Welding (FSW) is a solid state joining process that is widely used to produce high integrity aluminum weldments for a variety of industries. While extensive work has been conducted to understand flow behavior, much less research has been performed to identify how void defects form and how to predict them. In the present study, the relationship between rotation speed, plasticized region, and defect formation was investigated. To analyze how tunneling and cavity type void defects form during FSW, a 3-D Computational fluid dynamics(CFD) model based on the Fluent software code was used to simulate butt welding. The CFD …

Effect Of Diffusion Distance On Evolution Of Kirkendall Pores In Titanium-Coated Nickel Wires, Aaron R. Yosta, Dinc Erdeniz, Ashley E. Paz Y Puente, David C. Dunanda

Mechanical Engineering Faculty Research and Publications

Microtubes of near-equiatomic nickel-titanium (NiTi) alloys can be created via the Kirkendall effect during NiTi interdiffusion, when nickel wires are surface-coated with titanium via pack cementation and subsequently homogenized. This study explores the effect of diffusion distance upon Kirkendall microtube formation in NiTi by considering a range of Ni wire diameters. For Ni wire diameters of 25, 50 and 100 μm, titanized at 925 °C for 0.5, 2, and 8 h to achieve average NiTi composition, partial interdiffusion occurs concurrently with Ti surface deposition, resulting in concentric shells of NiTi₂, NiTi and Ni₃Ti around a Ni …

An Efficient Monte Carlo-Based Solver For Thermal Radiation In Participating Media, Joseph Farmer, Somesh Roy

Mechanical Engineering Faculty Research and Publications

Monte Carlo-based solvers, while well-suited for accurate calculation of complex thermal radiation transport problems in participating media, are often deemed computationally unattractive for use in the solution of real-world problems. The main disadvantage of Monte Carlo (MC) solvers is their slow convergence rate and relatively high computational cost. This work presents a novel approach based on a low-discrepancy sequence (LDS) and is proposed for reducing the error bound of a Monte Carlo-based radiation solver. Sobols sequence – an LDS generated with a bit-by-bit exclusive-or operator – is used to develop a quasi-Monte Carlo (QMC) solver for thermal radiation in this …

Energy Lesson Design, Jessica Lyons

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

No abstract provided.

Pico-Grid Smart Homes Power Management System, Kathleen Hobbs, Mbonya Myers

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

No abstract provided.

Development Of A Sensing System For Underground Optic Fiber Cable Conduit Mapping, Sherif Bakr

All Graduate Theses, Dissertations, and Other Capstone Projects

The motivation of this research is to obtain an accurate three-dimensional (3D) layout of an underground conduit, which may be beneficial to optic fiber cable installers and engineers. A newly designed algorithm for 3D position tracking with the help of an inertial sensor and an encoder has been developed. Two types of representations (Euler angle and Quaternion) for orientation and rotation are also introduced, followed by several data pre-processing procedures. A sensing fusion method is utilized to overcome the accumulated errors introduced by the sensor drifting. Considering the application of 3D underground duct mapping in this research, a sensing system …

Flow Fields Past Grain Bins As It Relates To Vertical Axis Wind Turbine Placement Optimization, Jon Richter

All Graduate Theses, Dissertations, and Other Capstone Projects

This thesis studies the 3D flow field of grain bins as it relates to Vertical Axis Wind Turbine (VAWT) placement. Numerical CFD simulations using ANSYS FLUENT were created and validated with the Minnesota State University, Mankato water channel. It was found that the best speed-up regions were on the outer most sides of the models, closest to the walls of the water channel. The model that is furthest upwind in the group has the best speed-up velocity. As the models become closer together, an asymmetric flow field develops. VAWT placement between the models for any case researched is not recommended. …

Flexure Properties Of 3d Printed Nylon Carbon Fiber Composite And Stiffness Of 3d Printed Modified Cuttlefish Bone Structure, Shashikanth Reddy

Electronic Theses and Dissertations

Flexure strength is one of the most widely used mechanical properties to represent the mechanical behavior of the composite. Fiber reinforcements increase the flexure strength of a composite. Specifically, there has been tremendous growth in the use of Carbon Fiber (CF) in the manufacturing industry due to its significant contribution to enhance the mechanical properties of a composite. Fiber orientation, void content, bonding between the layers (delamination), and fiber distribution are some of the factors that affect the flexure strength of a reinforced composite. The laminate (composite with reinforced layers) composites, has been a focus of study by researchers from …

Ua66/2 Ogden College Of Science & Engineering Architectural & Manufacturing Sciences, Wku Archives

WKU Archives Collection Inventories

Records created by the Architectural & Manufacturing Sciences.

Files are arranged in the following subseries:

1. Administration
2. Publications
3. Centers & Institutes

Ua66/9/2 Ogden College Of Science & Engineering Engineering Publications, Wku Archives

WKU Archives Collection Inventories

Publications created by and about the Engineering department.

Ua66/9/3 Ogden College Of Science & Engineering Engineering Student Organizations, Wku Archives

WKU Archives Collection Inventories

Records created by and about Engineering department student organizations.

An Energy Profile Model For Fused Deposition Modeling 3d Printing Process, Calvin Hawkins

Research Opportunities for Engineering Undergraduates (ROEU) Program 2018-19

This project develops a strategy to monitor and estimate the energy consumption of fused deposition modeling (FDM) additive manufacturing, which will benefit manufacturers and designers seeking to design and manufacture products with minimal energy consumption.

Compressive And Rheological Deformation Analysis Of Large Area Pellet-Fed Material Extrusion 3d Printed Parts In Relation To In Situ Thermal Imaging, Eduardo Meraz Trejo

Open Access Theses & Dissertations

In large area pellet extrusion additive manufacturing, the temperature of the substrate just prior to the deposition of a new subsequent layer has an effect on the overall structure of the part. Warping and cracking occur if the substrate temperature is below a specific threshold, but also deformation and deposition adhesion failure occur if the substrate temperature is above a certain threshold just prior to deposition of a new layer. Currently, Big Area Additive Manufacturing (BAAM) machine users mitigate this problem by trial and error, which is costly and may result in decreased mechanical properties, monetary losses and time inefficiencies. …

Cradle To Grave Lifecycle Process Analysis For Transuranic Waste Management Los Alamos National Laboratory, Cesar Enrique Dominguez

Open Access Theses & Dissertations

Amid World War II, in the late 1930s, nuclear fission was discovered. This revolution gave way to the development of nuclear technologies, including the world's first atomic bomb; these advancements in nuclear research left behind radioactive waste. Radioactive waste is known as the byproduct of nuclear reactors, fuel processing plants, hospitals, nuclear research facilities, as well as the result from the decommissioning and dismantling of radiation-exposed buildings and materials. This byproduct may be dangerous to workers, the public, and the environment and must, therefore, be handled with utmost safety. Given this, radioactive waste must be processed, stored, and disposed of …