Mechanical Engineering Commons^™

Design And Characterization Of A High Pressure Flow Loop For Heat Transfer Experiments Of Supercritical Carbon Dioxide, Joseph Sauerbrun

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide (sCO2) sees heightened heat transfer characteristics near its critical point due to its drastically changing thermophysical properties. Conventional single phase heat transfer theory was not developed to capture this nonlinear variation in properties and cannot predict the heat transfer characteristics of sCO2 to a practical level useful for design. To delve deeper into the behavior near the critical point and shed light on this crucial phenomenon, a state-of-the-art closed flow loop was developed. This setup enabled convective heat transfer experiments of sCO2 under diverse boundary conditions and test section geometries. Key components of the loop include the …

Explorations In Monocular Distance And Ranging (Modar) Techniques For Real-World Applications, Devon Vail

Doctoral Dissertations and Master's Theses

In this work, an initial prototype of a monocular camera system capable of retrieving depth-from-focus using a liquid focus-tunable lens is constructed out of hobby-grade photography equipment. This concept has been explored previously in laboratory settings using specialized equipment; this work seeks to determine the feasibility of retrieving depth-from-focus using commercially available components. To achieve this, an iterative exploration of existing techniques was performed to verify their utility in the final ensemble of processes to retrieve depth from 2D images. Initially, blurry images were simulated by applying Gaussian blur to test images to verify the functionality of a Laplacian of …

Elastic Sensing Skin For Monitoring Of Concrete Structures, Emmanuel Abiodun Ogunniyi

Theses and Dissertations

Soft elastomeric capacitors (SECs) are emerging as potential low-cost solutions for monitoring cracks and strains in concrete infrastructure, a crucial aspect of structural health monitoring. Effective long-term monitoring of civil infrastructure can reduce the risk of structural failures and potentially reduce the cost and frequency of inspections. However, deploying structural health monitoring (SHM) technologies for bridge monitoring is expensive, especially long-term, due to the density of sensors required to detect, localize, and quantify cracks. Previous research on soft elastomeric capacitors (SEC) has shown their viability for low-cost monitoring of cracks in transportation infrastructure. However, when deployed on concrete for strain …

A One-Dimensional Volcanic Plume Model For Predicting Ash Aggregation, D. W. Hoffman, L. G. Mastin, Alexa R. Van Eaton, Stephen Solovitz, Raul Bayoan Cal, J. K. Eaton

Mechanical and Materials Engineering Faculty Publications and Presentations

During explosive volcanic eruptions, volcanic ash is ejected into the atmosphere, impacting aircraft safety and downwind communities. These volcanic clouds tend to be dominated by fine ash (μm in diameter), permitting transport over hundreds to thousands of kilometers. However, field observations show that much of this fine ash aggregates into clusters or pellets with faster settling velocities than individual particles. Models of ash transport and deposition require an understanding of aggregation processes, which depend on factors like moisture content and local particle collision rates. In this study, we develop a Plume Model for Aggregate Prediction, a one-dimensional (1D) volcanic plume …

Development Of Pullulan/Chitosan/Salvianolic Acid Ternary Fibrous Membranes And Their Potential For Chemotherapeutic Applications, Salahuddin Ahmed, Megan Keniry, Victoria Padilla, Narcedalia Anaya-Barbosa, Md Noushad Javed, Robert Gilkerson, Kithzia Gomez, Acharan S. Narula, Karen Lozano

Mechanical Engineering Faculty Publications

This study investigates the feasibility of centrifugal spinning for producing fibrous membranes containing pullulan, chitosan, and danshen extract. The danshen extract is composed of 20 wt% salvianolic acid B (SA). Citric acid was added to the mixture as a crosslinking agent to promote its use in the aqueous medium. The influence of the danshen concentration (25 wt% and 33 wt%) on fiber morphology, thermal behavior, and the biochemical effect was analyzed. Developed fiber-based membranes consist of long, continuous, and uniform fibers with a sparse scattering of beads. Fiber diameter analysis shows values ranging from 384 ± 123 nm to 644 …

Effect Of Room Size, Shape, Ac Placement, And Air Leakage On Indoor Airborne Viral Transmission, K. Choudhary, K. A. Krishnaprasad, ‪Nadim Zgheib, M. Y. Ha, S. Balachandar

Mechanical Engineering Faculty Publications

Highlights

• Statistical overloading is used to obtain spatio-temporal pathogen concentration.

• Symmetrically placed AC limits pathogen propagation over long distances.

• Well-mixed model captures room-averaged concentration for any shape and AC location.

• The pathogens level of mixing is reduced when AC is symmetrically positioned.

• Air leakage has insignificant impact on indoor pathogen distribution.

Abstract

We conducted Euler–Lagrange Reynolds-Averaged Navier–Stokes simulations with statistical overloading to investigate the effect of room shape, air-condition (AC) location, and the presence of an open window on indoor airborne viral transmission, particularly as it relates to the spatio-temporal distribution of viral-laden droplet nuclei. Two room geometries were …

Switching Methods For Three-Dimensional Rotational Dynamics Using Modified Rodrigues Parameters, Matthew Jarrett Banks

Mechanical & Aerospace Engineering Theses & Dissertations

A rigid body in space has three degrees of rotational freedom. As a result, a minimum of three independent parameters is required to define the three-dimensional orientation of a rigid body. As is well known, every set of three independent parameters has at least one orientation where mathematical or geometrical singularities are encountered; therefore, when the use of a three-parameter representation is desired, a method for singularity avoidance must also be considered. A common practice for singularity avoidance is to switch between parameter sets whose singularities occur at different orientations. With this in mind, modified Rodrigues parameters (MRP) are considered …

The Effect Of Through Thickness Reinforcement Angle On The Disbonding Behavior In Skin-Stringer Configuration, Christopher John Morris

Mechanical & Aerospace Engineering Theses & Dissertations

Post-cure through thickness reinforcement is a method used to increase the mechanical properties of composite laminates in the transverse direction. This study conducted a test on skin-stringer structures bonded together in three configurations using an epoxy or thermoplastic adhesive at the interface with reinforcing pins inserted through the laminate thickness located at the edge of the stringer at differing angles between -30º and 30º. The fabrication of these samples in configurations B and C consisted of the use of carbon fiber prepeg laminate at a ply orientation of [0₂90₂]_2s for the skin and [0 90] …

The Investigation Of A Likely Scenario For Natural Tornado Genesis And Evolution From An Initial Instability Profile, Alexios Nicolas Philippou, Kakkattukuzhy M. Isaac

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A likely mechanism for the little-understood tornado genesis is proposed and its numerical implementation is presented. The Burgers-Rott vortex with its axis in the vertical direction is introduced as an instability mechanism, and the flow field then evolves under the influence of the atmospheric pressure, temperature and density variations with altitude. Buoyancy effects are implemented using the Boussinesq model. Results are presented and discussed for a set of conditions including mesh type and size, different turbulence models, and a few different boundary conditions. Post-processed results of the transient simulations including animations contain a wealth of information to help analyze tornado …

2023 (Fall) Ensi Informer Magazine, Morehead State University. Engineering Sciences Department

ENSI Informer Magazine Archive

The ENSI Informer Magazine published in the fall of 2023.

Investigation And Analysis Of Circular Economy Indicators In The Manufacturing Industry, Dina Al Jamal

Theses

In the pursuit of sustainable development, the concept of the Circular Economy (CE) has emerged as a compelling and transformative alternative to the traditional linear economic model (i.e., take, make, use, dispose). The limitations of the linear economy in addressing contemporary global challenges have highlighted the urgency of adopting a more regenerative approach. Simply put, the circular economy aims to maximize the value extracted from available resources over their lifecycle, thereby ensuring the fulfillment of both current and future generations' needs. This thesis sheds light on a pivotal solution for effectively integrating circular economy principles into enterprises, thereby reinforcing sustainability. …

Water Quality Monitoring And Mapping Using Rapidly Deployable Sensor Nodes, Mohamed Abdelwahab

Theses and Dissertations

Efficient and continuous monitoring of water quality parameters plays a pivotal role in responding to pollution incidents and ensuring the safety of both human consumption and ecological resources. This research introduces an affordable and dependable in-situ water quality sensor package designed for seamless continuous monitoring, providing essential data to facilitate informed decision-making in water resource management. The sensor package enables comprehensive on-site assessment of key water characteristics, including pH, temperature, turbidity (measured in NTU), and total dissolved solids (TDS, measured in ppm). Spatial interpolation techniques, specifically Kriging, are employed to extrapolate variable values at unobserved locations based on nearby measurements. …

Studies Of Damage Tolerance In Automated Fiber Placement Based Heterogeneous Meso-Architectured Carbon/ Epoxy Composite Laminates., Karan Kodagali

Theses and Dissertations

Traditional unidirectional (UD) carbon fiber-reinforced polymer matrix composites manufactured via automated fiber placement (AFP) are widely used in aerospace structures. While heterogeneous at the micro-scale, these materials are homogeneous at the meso-scale (ply-scale). The major limitation is its limited toughness, poor damage tolerance/impact resistance capability and the inability to sufficiently redistribute stresses, resulting in strength-toughness tradeoffs, making them susceptible to impact damage. From previous studies, there is an understanding that fiber architecture has a first order effect on the damage tolerance. Introducing new discontinuous/heterogeneous meso-scale architectures, through an optimal merger of material and structure, can result in unprecedented property improvements …

Design And Implementation Of An Optimization Platform For Common Fixed Photovoltaic Systems, Amro Ahmad Zahrawi

Mechanical Engineering Theses

Most household photovoltaic (PV) panels are installed in a fixed arrangement (fixed-type) based on a rule of thumb that comes from experience. The azimuth angle is usually set facing south with a tilt angle equivalent to the location's latitude. However, research shows that this is not the best for all geographical locations and during all hours of the day. Consequently, this brings up the hypothesis that optimizing the PV system's azimuth and tilt angles would ensure that the PV panel produces the most possible output as it is adjusted to face the sun most effectively during peak sunlight hours. This …

Introduction To Vacuum Technology, David M. Hata, Elena V. Brewer, Nancy J. Louwagie

Milne Open Textbooks

Vacuum systems are critical to many industries. They are vital to establishing required process pressures, establishing a clean process environment, and removing reaction by-products from the process chamber. This text, a revision and expansion of David Hata’s Introduction to Vacuum Technology published in 2008, addresses basic topics in vacuum technology for individuals tasked with maintaining vacuum systems and instructors teaching technician-level courses. The topics are carefully curated to the needs of technicians in a production environment and the types of vacuum systems used, and the accompanying laboratory manual and instructor’s guide support the delivery of lecture-laboratory courses.

This book approaches …

Development Of Prediction Method For Dimensional Stability Of 3d-Printed Objects, Kyung-Eun Min, Jae-Won Jang, Jesik Shin, Cheolhee Kim, Sung Yi

Mechanical and Materials Engineering Faculty Publications and Presentations

Fused deposition modeling (FDM), as one of the additive manufacturing processes, is known for strong layer adhesion suitable for prototypes and end-use items. This study used a multiple regression model and statistical analysis to explore the dimensional accuracy of FDM objects. Factors such as inclination angle, layer thickness, support space, and raster angle were examined. Machine learning models (Gaussian process regression (GPR), support vector machines (SVM), and artificial neural network (ANN)) predicted dimensions using 81 datapoints. The mean squared dimensional error (MSDE) between the measured and designed surface profiles was selected as an output for the dimensional accuracy. Support spacing, …

Me-Em Enewsbrief, September 2023, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Real-Time Product Structural Validation For Fused Filament Fabrication, Yanzhou Fu

Theses and Dissertations

Fused filament fabrication (FFF) is one of the fastest-growing, most promising, and widely-used Additive manufacturing (AM) technologies, as its capabilities of largely reducing material waste, feasible and flexible designing complicated structure or geometry product. Except for the advantages mentioned above, the unique affordability has made FFF a popular technique for small-scale 3D printing. However, its widescale adaption for industrial applications still faces significant challenges, especially for Industry 4.0, due to the process’s intrinsic uncertainties. During the printing process, even a trivial bonding gap or material void dramatically influences the final product’s structural quality and mechanical properties. Therefore, a defect detection …

Rational Design Of Complex Oxides By Understanding Structure-Property Relationships For Energy Applications, Gene Yang

Theses and Dissertations

Developing novel energy materials is a key step toward satisfying the needs for next-generation energy conversion and storage devices. Complex oxides are widely used in many energy technologies owing to their fascinating properties, including electrocatalytic activity, and ionic and electronic conductivity. In particular, oxides in thin film form yield many intriguing physicochemical properties that are unattainable in bulk oxides and thus have become critical to improving the performance of many energy devices, such as fuel cells, batteries, solar cells, and thermoelectric devices. This thesis is centered on designing oxide thin films and nanostructures via pulsed laser deposition (PLD) based on …

Synthesis And Characterization Of Electrode Materials Of Solid Oxide Cells For Energy Conversion And Storage, Haixia Li

Theses and Dissertations

Solid oxide cells (SOCs) can directly convert chemical energy to electricity in the fuel cell mode and store electricity to chemicals in the electrolysis mode. However, there are still critical barriers, such as energy efficiency and durability, for developing and commercializing SOCs. This dissertation aims to design electrode materials and optimize the cell fabrication process to address the critical barriers for SOCs in energy conversion and energy storage applications. Therefore, one primary focus of the dissertation is to develop robust fuel electrode material for solid oxide fuel cells (SOFCs) with improved sulfur tolerance. In addition, the design of novel fuel …

Wide View And Line Filter For Enhanced Image Gradient Computation And Edge Determination, Luke Bagan

Theses and Dissertations

Edge determination is a challenging yet crucial step in the object detection process for images. It is the first in a multi-step process, serving as the foundation for all subsequent operations. Its accuracy directly affects the success of any future processing techniques and final detection. The challenge of edge detection is derived from a variety of factors, including noise, image sharpness, orientation, empirical parameters, and computational complexity. Many traditional kernel-based operators excel at tackling one of these problems, but trade off their ability to handle others. For example, the popular Sobel operator uses a horizontal and vertical constant high-pass kernel. …

Particle-Free High Spatial Resolution Velocimetry For Slip Flow Detection, Malhar Prasad Joshi

Theses and Dissertations

Microfluidic systems have a wide range of applications, including biomedical devices, lab-on-a-chip technologies, and aerospace propulsion. Understanding and quantifying the slip flow phenomenon in these microscale and nanoscale channels is of paramount importance for precise control and optimization of fluidic processes. Our study presents a novel approach to directly measure the velocities in a microchannel using Laser Induced Fluorescence Photobleaching Anemometer (LIFPA) and Travel Time After Photobleaching Velocimetry (TTAPV). In this experimental study, microchannels with micrometer dimensions were used, and slip flow conditions controlled. The LIFPA-TTAPV approach was applied to measure slip velocities in the near wall regime, providing accurate …

Real-Time Edge Computing For Autonomous Systems, Junlin Ou

Theses and Dissertations

This research presents systematic studies and algorithmic and hardware development to enable real-time edge computing for autonomous systems, in particular, for robot path planning and localization applications. First, a low-cost, indoor, multi-camera positioning system is proposed to localize ground robots using the ArUco marker. In this system, the normalized coordinates of the marker processed by OpenCV are utilized to calculate the camera coordinates. Data-driven models are developed to establish a mapping relationship between the camera coordinates and the world coordinates of the marker. Fifty data pairs of the camera and world coordinate systems within one camera view (150 pairs in …

Material Development And Optimization Of Solid Oxide Cells For Energy Conversion And Storage, Wanhua Wang

Theses and Dissertations

There has been an increasing interest in clean and renewable energy generation for highlighted energy and environmental concerns. Solid oxide cell (SOC) has been considered as one of the most promising technologies since it can convert chemical energy to electricity in the fuel cell mode and store electricity to chemicals in the electrolysis mode. The present work is devoted to materials development in both oxygen ion conducting SOC (O-SOC) and proton conducting SOC (P-SOC). The objective of this study is to design and optimize the electrolyte and electrode materials for SOC in energy conversion and energy storage applications. One major …

Acoustic-Emission Monitoring Of Lap Joint Fatigue Cracks, Siddharth Kannan

Theses and Dissertations

Structural integrity is a pivotal consideration in the field of engineering applications, and understanding the behavior of materials and joints under various loading conditions is critical. This thesis presents a novel approach to detect and analyze fatigue induced cracks in various test specimens using Piezoelectric Wafer Active Sensors. This approach is widely used in Structural Health Monitoring applications involving acoustic emissions that can be captured using PWAS which in turn gives the surface response to applied stresses. The ultimate goal of the research is to identify the length of a fatigue crack originating from lap joints and to develop a …

A Globalized Optimization Schema For Automated Fiber Placement Processing Parameters, Matthew John Godbold

Theses and Dissertations

Automated Fiber Placement is an advanced manufacturing technique for industrial-scale composite structures. Advanced robotics coupled with composite manufacturing results in faster and more consistent results than previously obtained through hand layup. The complexity and interconnectedness of the automated fiber placement process provides a difficult challenge for traditional modeling techniques. Modeling within automated fiber placement currently utilizes physics-based modeling to inform the translation of a design to a manufacturing plan. The intricacy of the automated fiber placement process dictates that attempts at modeling or optimizing these processes are often limited in their scope. Physics-based modeling for manufacturing typically involves numerous interacting …

Mems 411: Mini-Golf Robot, Matthew J. Sullivan, Jack Nanez, William Urdahl, Eli Cohen

Mechanical Engineering Design Project Class

The following report details the design and construction of a mini-golf robot over
three months. The robot was designed under the standards provided by the
ASME Fall 2023 Design Challenge. The robot would need to traverse the mini-golf
course, completing it in under 10 minutes with the assistance of an attached striker
mechanism. It was necessary that the robot could position itself precisely with
respect to the goofball, while also staying stationary while striking the object. The
robot design timeline followed the guidelines of the engineering design process, with
concept generation, concept selection, prototype embodiment and design refinement
all playing …

Mems 411: Swing Energy Demo, Joshua Yoon, Owen Culver, Angel Wan, Gabriel Myong

Mechanical Engineering Design Project Class

A device to demonstrate the energy processes of a swing was created with the intention of display at the St. Louis Science Center.

Designing A Model Of Solar Photovoltaic Water Pumping System For Off-Grid Localities In Tanzania, Imani Mruma

Tanzania Journal of Engineering and Technology (TJET)

Modeling of photovoltaic (PV) water pumping system for rural water localities is vital especially in these modern days, in Tanzania. This is due to the rise of high number of solar-powered rural water projects constructed lacking appropriate design. The fate result into poor and substandard projects delivering below expectations. Kikombo Solar Water Project situated in Dodoma; Tanzania is one among poorly designed solar project chosen as a case study to validate proposed model. The main problem of Kikombo project is unsatisfactory amount of water from domestic points to satisfy population demand. This matter has been raised by pumping-station attendants and …

Extraction And Characterization Of Fibres From The Bark Of Ficus Nekbudu Tree, Liberato V Haule

Tanzania Journal of Engineering and Technology (TJET)

This paper investigates the extraction and characterization of fibres from the bark of the ficus nekbudu tree. The Ficus Nekbudu Fibres (FNF) was extracted from the bark by retting in water and then treatment with sodium hydroxide solution. The extracted FNF was analysed for chemical composition, physical, tensile, surface, structural and thermal stability properties. Findings on the chemical composition indicated that FNF has cellulose (49.9 %), lignin (13.4%), ash (7.1%) and water content (8.1%). From the physical investigation it was found that FNF has density (1.42 ± 0.005 g/cm3) and moisture regain (9.2 ±0.3%). From mechanical investigation it was found …