Mechanical Engineering Commons^™

Using Scaffolding, Gamification, And Self Awareness To Create Responsive Ux/Ui In Cad Software To Nurture Metacognition In Novice Users, Obed Ibrahim Gonzalez

Graduate Theses and Dissertations

Computer-aided Design (CAD) software represents a significant shift from manual and analog design processes to digital workflows, offering substantial utility, accuracy, and productivity benefits. However, CAD software often presents a steep learning curve, particularly for novice users who are new to the software or possess only basic knowledge. Traditional CAD curricula have predominantly focused on technical problem-solving—teaching tools and systems—while often neglecting strategic knowledge that encompasses reflection, planning, and refining, which are essential components of metacognition. Metacognition is crucial for transforming novices into experts who use fewer and more complex commands, employ sophisticated planning, and achieve their goals more efficiently. …

Development And Investigation Of A Novel Near-Wall Methodology For Large-Eddy Simulation Based On Dynamic Hybrid Rans-Les, Michael Tullis

Graduate Theses and Dissertations

The use of computational fluid dynamics (CFD) to test engineering designs with reduced cost and time compared to physical testing has become increasingly common in a range of industries and research fields. While numerical methods exist that can accurately solve the equations that govern the flow of fluids, these methods are computationally expensive for practical engineering problems due to the large amount of computational power needed to resolve the fluid flow over the entire range of length and time scales. Several different approaches have been introduced to address this computational cost issue, namely Reynolds-averaged Navier-Stokes (RANS) modeling and scale resolving …

Effects Of Thermal Interface Materials On Thermal Conductivity Measurement Using A Modified Astm D5470 Thermal Resistance Tester, Chinmaya Joshi

Mechanical Engineering Undergraduate Honors Theses

In this paper, we have investigated the effect of thermal interface materials (TIMs) on the accuracy and uncertainty of thermal conductivity measurements. A modified ASTM D5470 thermal resistance tester (TRT) is developed to measure the out-of-plane thermal conductivity of pyrolytic graphite (PG) and grade 2 titanium (TiG2) with and without TIMs. Compared to the ASTM D5470 standard, this modified design uses three thermocouples per side to support regressive analysis and explores the use of TIMs.s Nine PG samples and four TiG2 samples of varying thickness have been tested to obtain thermal resistance as a function of sample thickness. The steady-state …

Validating An Electronics Cooler Experiment And Optimizing Its Performance Using Ansys Icepak, Daniel V. Curl

Mechanical Engineering Undergraduate Honors Theses

Researchers at the University of Arkansas' Mechanical and Electrical Engineering Research Departments have designed and built a cold plate and substrate design for a 10 kV SiC MOSFET power module. Many variables define the design of the cold plate and substrate system and have quantifiable effects on the device’s performance. These variables include but are not limited to geometry and material selection of the fins and substrate. Manufacturing many test designs, running experiments, and comparing their performance is a time-consuming and expensive design optimization method that may be effective for some low-cost applications. Still, simulation is often a more cost-effective …

Exploring Metal Additive Manufacturing In Martian Atmospheric Environments, Zane Mebruer

Mechanical Engineering Undergraduate Honors Theses

On-surface manufacturing is key to the success of a planetary colonization, especially that of Mars. However, traditional subtractive manufacturing processes are equipment, energy, and material intensive, meaning novel additive manufacturing (AM) processes must be pursued for this end. Selective laser melting, one of the most effective and versatile AM methods, would be incredibly beneficial to a Martian mission but requires an artificial argon atmosphere to create effective parts. The purpose of this study was to examine if carbon dioxide, the gas that makes up over 95% of Mars’ surface atmosphere, would be a sufficient substitute for argon in SLM fabrication. …

Introduction To Building Energy Modeling And Analysis Using Energyplus, Jackson C. Burnett

Mechanical Engineering Undergraduate Honors Theses

Retail stores are dynamic environments where human activities significantly influence energy consumption patterns, particularly affecting heating, ventilation, and air conditioning (HVAC) demands. Existing energy models, such as those developed using EnergyPlus, often rely on generalized assumptions about human occupancy and behavior, leading to discrepancies between predicted and actual energy usage. This research aimed to enhance the accuracy of energy modeling for retail stores by conducting a sensitivity analysis of occupancy using EnergyPlus simulations. The study investigated how variations in occupancy levels impact HVAC loads, cooling and heating demands, and overall energy use. Results showed that increasing occupancy leads to higher …

Thermal Characterization Of 3d Printing Materials For Increasing Insulation Potential And Practicality, Jackson H. Minnick

Mechanical Engineering Undergraduate Honors Theses

This study served as an exploration into the possible existence of a correlation between the infill lattice structure of a 3D printed wall section and the thermal performance of that sample as characterized by thermal conductivity measured in units of Watts per meter Kelvin. With the continual increase in the practicality, fidelity, and applicable fields of additive manufacturing, namely FDM 3D printing, research on specific print characteristics and their effects on the material and thermal characteristics of the part in question is steadily becoming more commonplace. Although the thermal conductivity of 3D printed wall sections as a function of infill …

Causes And Contributing Factors In General Aviation Fixed-Wing Stall And Spin Accidents, Lauren Westfall

Mechanical Engineering Undergraduate Honors Theses

General Aviation operations are all civil aviation operations excluding commercial airline operations and cargo transport. General Aviation accidents comprise approximately 94% of all aviation accidents in the United States annually. Stall and spin accidents are the third most common causes of fatal General Aviation accidents, accounting for 7.28% of such accidents in 2013–2022. The National Transportation Safety Board investigates and records all General Aviation accidents in the United States. Using the National Transportation Safety Board’s accident database, I investigated stall and spin accidents between 2013 and 2022 to find (1) the most common phases of flight where stall and spin …

Agent-Based Modeling For Faulty System Analysis, Jayden G. Hamilton

Mechanical Engineering Undergraduate Honors Theses

Numerous approaches exist for computational modeling of complex, dynamic systems. One particular option is the use of agent-based modeling, which simulates the behavior of numerous autonomous agents interacting with each other and with the system at large. Current agent-based modeling research has largely focused on studying the system level behavior of a model, as this is generally the main concern for any real world application. However, the characteristics and behaviors of agents deserves consideration as well. The issue with this area of interest lies in the fact that the agent data cannot be as quickly obtained and analyzed as system …

A Labview-Based Open-Source Data Acquisition Program For Acoustic Emission Sensing, Harrison Greene

Mechanical Engineering Undergraduate Honors Theses

Acoustic emission sensing is a growing field of analysis and testing that benefits from its non-destructive nature, enabling operators to detect faults, the severity of impacts, the propagation of cracks, and much more without damaging the system being tested. However, the use of proprietary software to collect, analyze, and display data hinders the field, as access to this crucial information makes consistent and in-depth data analysis impossible. To this end, this paper details an open-source code made in the programming language LabVIEW for the express purpose of allowing the user to have full access to all data and fully customize …

Using Optical Dielectrophoresis For Microbead And Cell Manipulation, Leigh K. Smith

Mechanical Engineering Undergraduate Honors Theses

Dielectrophoresis is a common method used to manipulate particles on the microscopic scale. Optically Induced Dielectrophoresis or ODEP is the specific method used in this research. All experiments were conducted in Dr. Tung’s Micro and Nano Systems lab at the University of Arkansas’ ENRC. An ODEP system was created in the lab for manipulating microbeads (6-10 micrometers (μm) in diameter) and E. coli cells (1-2 μm in diameter).

Experiments were performed on the microbeads to see how changing the parameters of the device affects the force caused by ODEP on the beads. The parameters that could be changed in the …

Optimal Parameters For Electrode Free Local Anodic Oxidation Lithography, Maxwell C. Cleveland

Mechanical Engineering Undergraduate Honors Theses

Dr. Steve Tung’s research lab is developing a device for sequencing DNA strands. A key component of this device is a nano sensor fabricated using monolayer graphene. To create the sensor, the graphene must be precisely patterned. Graphene, a single layer of carbon atoms, is an ideal material for detecting electrical signals from DNA bases due to its excellent conductivity.

The current fabrication method uses Atomic Force Microscopy (AFM) in combination with Electrode-Free Local Anodic Oxidation (LAO) lithography. While AFM is typically employed for nanoscale imaging, pairing it with LAO lithography enables the patterning of graphene into nanoribbons capable of …

Small Laser-Textured Dimples For Improved Tribological Performance Of Cocrmo In Artificial Hip Joints, William B. Bennett, Min Zou

Mechanical Engineering Faculty Publications and Presentations

This study investigates the impact of small dimples on the tribological properties of CoCrMo (CCM) surfaces. Laser-ablated textures with 5 mu m diameter dimples were fabricated at varying aspect ratios (0.1, 0.2, 0.3) and surface densities (5%, 15%, 25%) to evaluate their effects on friction and wear when paired with ultra-high molecular weight polyethylene (UHMWPE) counterfaces. The results showed that small dimples significantly reduced and stabilized the coefficient of friction (CoF) and wear compared to untextured CCM and larger dimples as reported in the literature. The texture configuration with a 5% surface density and 0.1 aspect ratio achieved the best …

Rfid Occupied Advanced Framework For Specialized Vehicle Access, Operating System, And Wireless Data Transmission Without Human Intervention, Abdullah Al Mamun Anik, Mosammet Sadia Akter Moon, Fahim Faysal Arnob, Mehedi Hasan, S. A. Naimal Hoque, Mohammad Mashhunar Rahman, Tahzin Bin Ahmed, Tonmoy Barua

Mechanical Engineering Faculty Publications and Presentations

Radio frequency identification system (RFID) tags are tiny electronic devices that include a distinctive code that can be detected by a reader that supports RFID. The string of characters is used for recognizing and monitoring the object to which the tag is connected. RFID tags interact with RFID readers using radio frequency. While the tag comes into close proximity to the scanner, that device sends a radio signal that triggers the tag. The tag then responds by sending its unique identity. RFID pinpointing ability is verified experimentally in two different techniques, one utilizing radar and the other a photosensitive transition. …

Accurately Constituting Robust Interfaces For High-Performance High-Energy Lithium Metal Batteries, Kevin V. Carballo, Meetesh Singh, Xiangbo Meng

Mechanical Engineering Faculty Publications and Presentations

High-energy lithium metal batteries (LMBs) have received ever-increasing interest. Among them, coupling lithium metal (Li) with nickel-rich material, LiNi_xMn_yCo_zO₂ (NMCs, x ≥ 0.6, x + y + z = 1), is promising because Li anodes enable an extremely high capacity (∼3860 mA h g⁻¹) and the lowest redox potential (−3.04 V vs. standard hydrogen electrode), while NMCs can achieve a much higher capacity of ∼200 mA h g⁻¹ and lower cost than those of LiCoO₂. However, the resultant Li‖NMC cells have been hindered from commercialization due to a …

Advanced Numerical Techniques For Multiscale Simulations In Biofluid Dynamics, Justin Tamico Jack

Graduate Theses and Dissertations

The study of anisometric particle suspensions and congenital heart defects (CHDs) involve exploring complex phenomena within the biological sciences. The former subject dives into the phase behavior of liquid crystals (LCs), particularly the influence of the shape anisotropy of rod-like nanoparticles on phase transitions, through the implementation of statistical techniques involving molecular dynamics (MD). Conversely, the latter topic focuses on the assessment and management of severe congenital arterial stenoses, such as those found in Williams-Beuren syndrome (WS), through advanced multi-scale computational fluid dynamics (CFD) simulations. Both areas emphasize the importance of detailed analysis and the use of advanced numerical modeling …

Development Of A Manifold Microchannel Heat Sink For The Electrification Of Aircraft, Joshua Mora Sanchez

Mechanical Engineering Undergraduate Honors Theses

The miniaturization of microprocessors and power electronics is leading to critical thermal management challenges. For instance, the heat flux generated in modern computer chips is at the order of 100W/cm², which is well beyond the limit of air cooling. This high heat generation can cause a variety of thermal or mechanical failures in electronic devices. As such, there is a pressing need to devise effective cooling strategies for these microelectronic devices. Liquid cooling with microchannel heat sinks is a promising technology for high power loads. Nevertheless, traditional heat sinks with straight microchannels suffer from two critical challenges: high pressure drop …

Lithicone-Protected Lithium Metal Anodes For Lithium Metal Batteries With Nickel-Rich Cathode Materials, Ridwan A. Ahmed, Kevin V. Carballo, Krishna P. Koirala, Qian Zhao, Peiyuan Gao, Ju-Myung Kim, Cassidy S. Anderson, Xiangbo Meng, Chongmin Wang, Ji-Guang Zhang, Wu Xu

Mechanical Engineering Faculty Publications and Presentations

The high energy density advantage of lithium (Li) metal batteries (LMBs) makes them increasingly desirable; however, problems such as strong reactivity and dendrite growth of Li metal anode limit their practical uses. In this work, a novel Li-containing glycerol (LiGL) or lithicone protection layer on a 50 μm thick Li metal anode is employed for improving the performance of LMBs. This LiGL layer was accurately deposited via a molecular layer deposition (MLD) process at 150°C, using lithium tert-butoxide and glycerol as precursors. The as-formed LiGL coating layer is highly tunable in its thickness by simply adjusting MLD cycles and shows …

Multimodal Boiling Dataset With Synchronized Acoustic, Optical, And Thermal Measurements Under Steady-State And Transient Heat Loads, Hari Pandey, Changgen Li, Han Hu

Mechanical Engineering Faculty Publications and Presentations

Boiling is a high-performance heat dissipation process that is central to electronics cooling and power generation. However, there exists a practical limit of boiling heat transfer known as the critical heat flux (CHF), beyond which significant performance degradation is observed. Understanding the physical mechanism that triggers CHF is essential to meet the increasing cooling demands driven by power densification and device miniaturization. However, the high dimensionality, stochasticity, and dynamicity of the boiling process have led to strong challenges in the experimental characterization and modeling of boiling CHF. As such, high-frame rate, high-resolution, multi-physics boiling datasets are critical to advancing the …

Synthesis Of Silica-Encapsulated Myristic Acid Phase-Change-Assisted Nanocapsules For Thermal Management Applications, Muhammad Ghufran, David Huitink

Mechanical Engineering Faculty Publications and Presentations

Myristic acid-based silica (MA/SiO₂) nano-encapsulated phase change materials (NePCMs) were synthesized by the sol–gel process. Five different samples of the MA/SiO₂ nanocapsules were prepared by varying the mass of the myristic acid. The nanocapsules were characterized by Fourier transform infrared spectrophotometer (FTIR), X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), energy dispersive X-ray (EDX), and dynamic light scattering (DLS). These characterization techniques confirmed the successful encapsulation of the myristic acid inside the silica shell. The maximum latent heat was found to be 114.46 J/g for the sample which was prepared with 25 g myristic …

Caring: Cannula For Alleviation Of Retinal Injury Caused By Needle Fluidic Gashing, Kaersti L. Rickels, Anthony L. Gunderman, Mattie S. Mclellan, Muhhamad M. Shamim, Joseph A. Sanford, Sami H. Uwaydat

Mechanical Engineering Faculty Publications and Presentations

Infusion-related iatrogenic retinal breaks (IRBs) are a significant complication in vitrectomies, particularly when smaller-gauge cannulas are used during fluid infusion. Using two-dimensional finite element analysis (FEA), we analyzed forces exerted on the retina from different cannulas: traditional 25-gauge, 20-gauge, 23-gauge, and 27-gauge, then investigated four alternative new cannula designs: (A) oblique orifices, (B) external obstruction, (C) side ports, and (D) perpendicular orifices. The analysis revealed that the standard 25-gauge cannula had a force of 0.546 milli-Newtons (mN). Optimized cannulas demonstrated decreased forces: 0.072 mN (A), 0.266 mN (B), 0.417 mN (C), and 0.117 mN (D). While all the designs decrease …

Settingsorder Article Reprints Open Accesseditor’S Choicearticle Exploring The Impact Of Spray Process Parameters On Graphite Coatings: Morphology, Thickness, And Tribological Properties, Adedoyin Abe, Josue A. Goss, Min Zou

Mechanical Engineering Faculty Publications and Presentations

This study explores, through a full factorial experimental design, the effects of graphite concentration and spray flow rate on the morphology, thickness, and tribological performance of graphite coatings for potential tribological applications. Coatings were applied to rough substrates using varying concentrations and flow rates, followed by analysis of their morphological characteristics, roughness, thickness, coefficient of friction (COF), and wear behavior. The results revealed distinct differences in the coating morphology based on flow rate, with low-flow-rate coatings exhibiting a porous structure and higher roughness, while high-flow-rate coatings displayed denser structures with lower roughness. A COF as low as 0.09 was achieved, …

The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough

Physics Undergraduate Honors Theses

Mechanical Exfoliation

Dna/Carbon Nanotube Hybrid Structure And Their Translocation Through A Nanochannel, Daniel Christoffel Viljoen

Graduate Theses and Dissertations

DNA sequencing is of major importance as it is used in fields such as species differentiation, personalized medicine and food safety. Currently sequencing by synthesis is the most popular commercial method of sequencing DNA while Oxford nanopore’s protein based nanopores are the only portable commercial method. Current nanopore based devices have three main issues: Spacial resolution, translocation rate versus sensor strength and dealing with the persistence length of ssDNA. This thesis contributes to ongoing research that aims to create a nanochannel with integrated sensor based sequencing device. The project has two main objectives. The first objective is to improve the …

Flow Characterization With Acoustic Emission Sensing, Jackson Marsh

Mechanical Engineering Undergraduate Honors Theses

Acoustic emissions (AE) allow for non-intrusive sensing into many types of systems. In systems where there is flow of some type, AE is very useful as these types of systems can be characterized in many ways from the collisions or creation of the flow. Correctly setting up the AE system is extremely important. Failure to do so results in imprecision and inaccurate data being collected. Because of this synchronization techniques, sensor configurations, and data acquisition systems must all align. This can be done with off-the-shelf, commercial systems, but this does not allow for customization and the ability to tailor the …

Cam And Design For Manufacturing: Developing A Project-Based Learning Course, Stephen Pierson

Mechanical Engineering Undergraduate Honors Theses

To effectively serve student career success, mechanical engineering programs must teach students how to account for manufacturing considerations in design. Despite this, manufacturing education is a glaring area of need in current engineering curricula. In fact, basic manufacturing knowledge is one of the only hard skills consistently ranked as one of the greatest weaknesses of mechanical engineering hires in surveys of industrial employers over the last few decades. Without radically changing departmental curriculum to include more emphasis on design-build projects, one solution to combat this is to incubate a lab course in mechanical engineering programs in which undergraduates would practice …

Model-Based Comparison Of Biological Organism And Electro-Mechanical System Resiliency Strategies, Nicholas Ratycz

Mechanical Engineering Undergraduate Honors Theses

Bio-inspired design has been used by many engineers to solve difficult problems or to make manufacturing processes more efficient. Biomimetics is the study of implementing the structure or function of biological substances, materials, mechanisms, and processes onto artificial ones that mimic the original. The goal of the BIASD tool is to provide bio-inspiration for engineers by studying the fault-adaptive strategies that biological systems use, rather than just their structure or function. In this thesis, the fault adaptive strategies of both a biological example and that of a real cubesat are compared using three types of model-based system diagrams to show …

The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough

Mechanical Engineering Undergraduate Honors Theses

Mechanical Exfoliation of Graphene is an often-overlooked portion of the fabrication of quantum devices, and to create more devices quickly, optimizing this process to generate better flakes is critical. In addition, it would be valuable to simulate test pulls quickly, to gain insight on flake quality of various materials and exfoliation conditions. Physical pulls of graphene at various temperatures, pull forces, and pull repetitions were analyzed and compared to the results of ANSYS simulations, solved for similar results. Using ANSYS’ ability to predict trends in exfoliations, flake thickness and coverage using stress and deflection analyses were investigated. Generally, both strongly …

Large Eddy Simulation Of Fluid Mixing In Migadome Facility For The Astfe Nuclear Thermal Hydraulics Cfd Competition, Kolten Strauss

Mechanical Engineering Undergraduate Honors Theses

This paper is a documentation of a submission to the First Annual ASTFE Nuclear Thermal Hydraulics Computational Fluid Dynamics (CFD) Competition [1]. To validate simulations of turbulent mixing in buoyancy-driven flows, an air and argon test case was set up inside the University of Michigan’s MiGaDome mixing vessel. This submission to the competition used a polyhedral mesh of about two and a half hundred thousand cells, a Large Eddy Simulation (LES) of the MiGaDome, and the Wall-Adapting Local Eddy-viscosity (WALE) subgrid approximation model. The competition included a factor considering the energy cost of our simulations, so it was decided to …

Experimental And Numerical Investigation Of Air-Cooled Heat Sinks, Ethan Weems

Mechanical Engineering Undergraduate Honors Theses

Lightweight and affordable cooling capabilities are critical as the physical scale of electronics continues to decrease. Air-cooled heat sinks that dissipate heat from electronic components to the surrounding air are excellent candidates to fill this role. While plate-fin and pin-fin heat sinks have been implemented extensively for electronic cooling, recent advances in additive manufacturing enable the fabrication of more complex structures. In this undergraduate Honors thesis, a means by which to generate novel heat sink geometries is presented. To that end, an experimental characterization facility is developed to evaluate existing traditional heat sinks. The heat transfer performance of the heat …