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Articles 31 - 60 of 513
Full-Text Articles in Mechanical Engineering
Retrofitting Farm Equipment With Airflow Sensors, Jacob Bybee
Retrofitting Farm Equipment With Airflow Sensors, Jacob Bybee
Undergraduate Honors Capstone Projects
In the Fall of 2024, our farm in Idaho upgraded our equipment from conventional seeding drills to more modern and sophisticated air seeder drills, particularly the John Deere 1900 Commodity Air Cart and John Deere 730 Air Disk Drill. In our case, this equipment was purchased used at an auction and had been a little modified. One modern convenience that this certain 730 Drill did not come with was a blockage monitoring system to alert the operator that a seed distribution tube was no longer distributing seeds. My question the became: Can an affordable, reliable airflow sensor system be designed …
Training Lander For Rover Arm Testing, James Peck
Training Lander For Rover Arm Testing, James Peck
Undergraduate Honors Capstone Projects
The purpose of this honors capstone project is to design and fabricate a training lander to support the Utah State University (USU) rover team in preparation for the University Rover Challenge (URC). The URC is an international collegiate competition featuring four missions, one of which—the Equipment Servicing Mission—demands a high level of robotic arm functionality and operator skill. Historically, USU's rover teams have struggled to qualify for the URC finals, in part due to limited hands-on training opportunities with the robotic arm.
To address this gap, the training lander replicates the tasks found in the URC Equipment Servicing Mission, such …
Quantifying The Threshold For Fragmentation Of Newtonian And Non-Newtonian Drops, Aditya Parik
Quantifying The Threshold For Fragmentation Of Newtonian And Non-Newtonian Drops, Aditya Parik
All Graduate Theses and Dissertations, Fall 2023 to Present
This dissertation investigates how the properties of liquid drops influence the minimum aerodynamic forces needed to cause the drop to fragment (breakup). For this work, we focus only on aerodynamic forces that are applied on a stationary drop by a sudden, uniform flow, a process called impulsive acceleration. Previous studies have largely focused on the fragmentation of spherical drops of Newtonian fluids (liquids with constant viscosity, like water), when impulsively accelerated in air-like ambient medium. Such systems only capture a limited range of drop and ambient properties (described by non-dimensional groups). Many real-world applications, such as aerial fire retardant delivery, …
Quantifying Buoyancy-Driven Exchange Flows Over Obstacle At The Great Salt Lake Using Rans Cfd, Mohammad Ikram Hossain Talukdar
Quantifying Buoyancy-Driven Exchange Flows Over Obstacle At The Great Salt Lake Using Rans Cfd, Mohammad Ikram Hossain Talukdar
All Graduate Theses and Dissertations, Fall 2023 to Present
This study examines how barriers, such as berms, affect the movement of water in the Great Salt Lake in Utah. The lake experiences two types of water flow: one, called a unidirectional gravity current, where denser water flows in a single direction, and another, known as buoyancy-driven exchange flow, where water flows in two opposite directions due to differences in both water density and surface elevation. These flows are important for understanding how water mixes and moves between the northern and southern parts of the lake. Using computer models, we simulated how these two types of water flows behave when …
Dynamics Of Rotating 2d Ellipse In Stratified Flow, Anton G. Kadomtsev
Dynamics Of Rotating 2d Ellipse In Stratified Flow, Anton G. Kadomtsev
All Graduate Theses and Dissertations, Fall 2023 to Present
Submersible vehicles that move through seawater are subjected to a variety of effects. Seawater has a non-uniform density because of uneven heating and the tendency of dense saltwater to sink. This non-uniform density distribution induced by gravity is known as stratification and introduces vertical confinement and internal gravity waves to flows around bodies. Along with translational motion, these vehicles also perform rotational motion. To identify the effects of density gradient, body shape, and rotation on the flow, 2D direct numerical simulations (DNS) are run and analyzed. The simulations are conducted using the open-source CFD solver Nek5000, utilizing its overset-grid-based methodology. …
Data Science For Engineers, Heidi Moulton
Data Science For Engineers, Heidi Moulton
Student Research Symposium
30% of USU undergraduate students participate in some sort of research, and for engineering students this often means generating large amounts of data.
Data Science for Engineers is a series of four modules that introduce students to data processing, visualization, and graphing in the Python programming language using Pandas DataFrames and Juypter Notebooks.
The modules are intended for students with a basic understanding of programming in Python, specifically those who have taken CS 1400 Introduction to Computer Science.
Simulating Low Gravity Particle Dynamics, Ryan Lewis
Simulating Low Gravity Particle Dynamics, Ryan Lewis
Student Research Symposium
- Vibrating motors prevent particle arches from forming and clogging nozzle.
- A metal mesh under the nozzle creates an evenly dispersed stream.
- Nozzle is static dissipative to ensure particles have consistent path through the charging section.
A Pressure-Based Estimate Of Multi-Orifice Synthetic Jet Performance, Rhett Parry
A Pressure-Based Estimate Of Multi-Orifice Synthetic Jet Performance, Rhett Parry
Student Research Symposium
Synthetic Jets
- Zero-Net Mass Flux
- Wide voltage and frequency response
- Trends with physical and nondimensional parameters
Atomistic Simulations Of Shape Memory Behavior And Negative Poisson's Ratio Effect Of Liquid Crystal Elastomers, Nanang Mahardika
Atomistic Simulations Of Shape Memory Behavior And Negative Poisson's Ratio Effect Of Liquid Crystal Elastomers, Nanang Mahardika
Student Research Symposium
- LCEs are suitable materials for soft robotics application because it is programmable, responsive to various stimuli and has flexibility.
Learning Partial Differential Equations Of Solid Diffusion From Atomistic Simulations, Wongel Nadew
Learning Partial Differential Equations Of Solid Diffusion From Atomistic Simulations, Wongel Nadew
Student Research Symposium
Why do we study diffusion in solid materials?
Lifting-Line Predictions For The Ideal Twist Effectiveness Of Spanwise Continuous And Discrete Control Surfaces, Zachary S. Montgomery, Douglas F. Hunsaker, James J. Joo
Lifting-Line Predictions For The Ideal Twist Effectiveness Of Spanwise Continuous And Discrete Control Surfaces, Zachary S. Montgomery, Douglas F. Hunsaker, James J. Joo
Mechanical and Aerospace Engineering Faculty Publications
Modern materials and manufacturing technologies have allowed the construction of morphing wings that are able to continuously vary certain airfoil parameters such as twist, camber, or control surface deflection as a function of span. This work presents a twist effectiveness parameter as a means of comparing the ideal aerodynamic efficiency of spanwise continuous control surfaces (morphing wings) and spanwise discrete control surfaces (standard wings). A numerical algorithm is used to compute the twist effectiveness of both continuous and discrete control-surface designs over a wide range of planform shapes with evenly spaced actuation for inviscid, incompressible flow. Results included here show …
Stabilizing A Bio-Inspired Rotating Empennage Fighter Aircraft In Multiple Trim Scenarios, Benjamin C. Moulton, Matthew W. Harris, Douglas F. Hunsaker
Stabilizing A Bio-Inspired Rotating Empennage Fighter Aircraft In Multiple Trim Scenarios, Benjamin C. Moulton, Matthew W. Harris, Douglas F. Hunsaker
Mechanical and Aerospace Engineering Student Publications and Presentations
This paper considers the problem of stabilizing a bio-inspired fighter aircraft at its Air Combat Maneuver Condition in steady level and coordinated-turning flight. The aircraft equations of motion are linearized, and an infinite-horizon linear quadratic regulator design is conducted. The open-loop system is unstable in the short period and Dutch roll modes. This is mitigated in the closed-loop system, which is analyzed in the time and frequency domains. Included in the simulation dynamics are first-order actuator models, actuator deflection limits, and actuator rate limits. These are particularly important for this bio-inspired aircraft because control actuation requires rotation of the empennage, …
Influence Of Process Parameter And Build Rate Variations On Defect Formation In Laser Powder Bed Fusion Ss316l, Tasrif Ul Anwar, Patrick Merighe, Rahul Reddy Kancharla, Boopathy Kombaiah, Nadia Kouraytem
Influence Of Process Parameter And Build Rate Variations On Defect Formation In Laser Powder Bed Fusion Ss316l, Tasrif Ul Anwar, Patrick Merighe, Rahul Reddy Kancharla, Boopathy Kombaiah, Nadia Kouraytem
Mechanical and Aerospace Engineering Student Publications and Presentations
Laser powder bed fusion (LPBF) is an additive manufacturing process that has gained interest for its material fabrication due to multiple advantages, such as the ability to print parts with small feature sizes, good mechanical properties, reduced material waste, etc. However, variations in the key process parameters in LPBF may result in the instantiation of porosity defects and variation in build rate. Particularly, volumetric energy density (VED) is a variable that encapsulates a number of those parameters and represents the amount of energy input from the laser source to the feedstock. VED has been traditionally used to inform the quality …
Finite-Time Control Strategies For Rendezvous And Proximity Operations, John Tamotsu Akagi
Finite-Time Control Strategies For Rendezvous And Proximity Operations, John Tamotsu Akagi
All Graduate Theses and Dissertations, Fall 2023 to Present
One common metric to use when designing a controller is the time that the system will take to reach the desired state. Unfortunately, many approaches to developing controllers only guarantee that the system will approach, but not exactly reach, the desired state. This can become a limitation in time-sensitive situations where rapid and complete convergence is necessary. One group of control methods, known as finite-time control, does guarantee both faster convergence and that the desired state will be reached, but often fails to define exactly what time that will occur, how much control will be used to get there, and …
Data-Driven Techno-Economic Analysis, Optimization, And Uncertainty Quantification Of Integrated Energy Systems In Deregulated Electricity Markets, Jacob A. Bryan
All Graduate Theses and Dissertations, Fall 2023 to Present
Electricity is a ubiquitous energy source in daily life, powering everything from stovetops and cellphones to vehicles and industrial processes. While wind and solar power have become increasingly common sources of electricity, the majority of electricity is still produced by burning fossil fuels, releasing greenhouse gases and propelling climate change. Wind and solar power cannot economically replace these fossil fuel energy sources on their own because they do not produce consistent power; the wind must be blowing, and the sun must be shining for them to make electricity. Nuclear power is a reliable source of energy that does not generate …
Quasi-Static Indentation Characteristics Of Foam-Filled Sandwich Composite Structures With Additively Manufactured Cfrp And Gfrp Corrugated Cores, S.Z.H. Shah, Juhyeong Lee, Khurram Altaf, M. Mohammad, M.Z. Hussain, R.S. Choudhry
Quasi-Static Indentation Characteristics Of Foam-Filled Sandwich Composite Structures With Additively Manufactured Cfrp And Gfrp Corrugated Cores, S.Z.H. Shah, Juhyeong Lee, Khurram Altaf, M. Mohammad, M.Z. Hussain, R.S. Choudhry
Mechanical and Aerospace Engineering Faculty Publications
This paper presents an experimental investigation on the quasi-static indentation performance of polyurethane (PU) foam-filled carbon fibre-reinforced polymer (CFRP) and glass fibre-reinforced polymer (GFRP) corrugated sandwich composite structures (SCSs) under different indenter tip geometries (conical, trapezoidal, hemispherical, pyramidal, and cylindrical shapes). The SCSs were produced using hybrid manufacturing methods: (1) the facesheets were fabricated using the vacuum-assisted resin infusion (VARI) process, (2) the CFRP and GFRP corrugated cores were additively manufactured using the fused filament fabrication (FFF) process, and (3) the self-expanding PU foam-filled the open spaces in the core. The results elucidated that the indenter tip geometry and core …
Development And Testing Of A Fast-Acting, 8-Bit, Digital Throttle For Hybrid Rocket Motors, Stephen A. Whitmore
Development And Testing Of A Fast-Acting, 8-Bit, Digital Throttle For Hybrid Rocket Motors, Stephen A. Whitmore
Mechanical and Aerospace Engineering Faculty Publications
The potential for throttle control of hybrid rocket systems has long been known as a potential advantage for a variety of applications. Because only a single flow path is controlled, theoretically, hybrids should be significantly easier to throttle than bipropellant systems. Unfortunately, the slow response times and nonlinearity of traditional position-control valves have limited practical applications of hybrid throttling. This paper presents an alternative throttling system where the oxidizer flow path is broken into multiple streams, with each flow path controlled by a solenoid-operated on/off valve. The parallel paths allow significantly faster and more precise control than can be achieved …
Multiscale Analysis Of Thermal Barrier Coated Cfrp Composites Under Thermal Loading, Devin Nielsen, Trenton M. Ricks, Juhyeong Lee
Multiscale Analysis Of Thermal Barrier Coated Cfrp Composites Under Thermal Loading, Devin Nielsen, Trenton M. Ricks, Juhyeong Lee
Mechanical and Aerospace Engineering Student Publications and Presentations
Carbon-fiber reinforced polymer (CFRP) composites are commonly used in high performance applications. Although offering several advantages (i.e., superior specific properties and improved structural rigidity), traditional CFRP composites often exhibit poor thermal stability due to a low matrix thermal decomposition temperature. The effective operating temperature of the CFRP composites can be raised by applying an outermost, protective thermal barrier coating (TBC) layer. Prefabricated high void content ceramic TBCs are ideal for composite applications due to their high thermal stability and relatively low thermal conductivity. In this paper, the thermo-mechanical response of the TBCCFRP composite laminate subjected to 500°C are assessed through …
Critical Comparison Of Potential Machine Learning Methods For Lightning Thermal Damage Assessment Of Composite Laminates, Juhyeong Lee, Scott L.J. Millen, Xiaodong Xu
Critical Comparison Of Potential Machine Learning Methods For Lightning Thermal Damage Assessment Of Composite Laminates, Juhyeong Lee, Scott L.J. Millen, Xiaodong Xu
Mechanical and Aerospace Engineering Faculty Publications
The present study assesses the potential of using machine learning (ML) methods to predict the extent of lightning thermal damage in fiber-reinforced composite laminates using three supervised machine learning (SML) algorithms: (1) linear regression (LR), (2) decision tree (DT)-based, and (3) MLP models. These models were based on the 10 most significant factors that influence the severity of lightning damage, including three current waveform parameters, four material configurations, and three orthogonal electrical conductivities of each composite. All models demonstrated good performance with coefficient of determination (R2) values between 0.84 ~ 0.96. The multilayer perceptron (MLP) regression model trained …
A Comprehensive Study On Long-Term Durability Of Protective Epoxy Coatings For Electrified Roadways, Md Tareq Hassan, Samiul Alam, Juhyeong Lee
A Comprehensive Study On Long-Term Durability Of Protective Epoxy Coatings For Electrified Roadways, Md Tareq Hassan, Samiul Alam, Juhyeong Lee
Mechanical and Aerospace Engineering Faculty Publications
Underground wireless power transmission (WPT) systems are susceptible to environmental threats such as high temperatures, water ingress, and mechanical impact from above-ground objects. Typical WPT systems electronics are safeguarded with civil-grade epoxy coating, thus it is imperative to assess the coating's durability in these extreme conditions. Among various environmental threats, this study is primarily focused on both experimental and numerical investigations on long-term water diffusion characteristics of civil-grade epoxy materials at various temperatures. A series of water diffusion tests were performed on the specimens made from two commercially available electronics casting epoxy materials at room (23°C) and high (50°C) temperatures. …
Performance-Tunable Thermal Barrier Coating For Carbon Fiber-Reinforced Plastic Composites Via Flame Spraying, Heejin Kim, Kandasamy Praveen, Min Wook Lee, Juhyeong Lee
Performance-Tunable Thermal Barrier Coating For Carbon Fiber-Reinforced Plastic Composites Via Flame Spraying, Heejin Kim, Kandasamy Praveen, Min Wook Lee, Juhyeong Lee
Mechanical and Aerospace Engineering Faculty Publications
Thermal barrier coatings (TBCs) are essential for improving the heat resistance of materials operating in high-temperature environments. This paper proposes a new method for manufacturing double-layered TBC with graded porosity for carbon fiber-reinforced plastic (CFRP) composites. The TBC was created by a flame spraying process, consisting of relatively dense and porous layers: (1) a dense layer was produced by spraying yttria-stabilized zirconia (YSZ) particles directly onto neat carbon fabric substrate and (2) a porous layer was prepared by co-spraying YSZ particles with sacrificial polyetheretherketone (PEEK) particles. The porosity of the porous layer was controlled by varying a PEEK injection distance …
Damage Of Nickel-Coated Glass/Epoxy Foam-Core Composites Induced By Artificial Lightning Strikes, Van-Tho Hoang, Won-Ho Choi, Juhyeong Lee, Chanyeop Park, Jin-Hwe Kweon, Byeong-Su Kwak, Young-Woo Nam
Damage Of Nickel-Coated Glass/Epoxy Foam-Core Composites Induced By Artificial Lightning Strikes, Van-Tho Hoang, Won-Ho Choi, Juhyeong Lee, Chanyeop Park, Jin-Hwe Kweon, Byeong-Su Kwak, Young-Woo Nam
Mechanical and Aerospace Engineering Faculty Publications
In the field of composite materials, many reports have shown that catastrophic structural damage is caused by lightning strikes. In this study, new design concepts were proposed for the lightning-strike protection of nickel-coated glass/epoxy foam-core composites. Instead of using a neat metal mesh, glass fibers were modified with nickel particles via a plating technique to improve their thermal and electrical conductivities. In addition, a thin Invar plate was inserted at the middle of the structure and a foam core was introduced to reduce damage to the structure. Three models with different materials and stacking sequences were used in this study. …
Utilizing Bayesian Optimization In Technoeconomic Analyses For Integrated Energy Systems, Anthoney Griffith
Utilizing Bayesian Optimization In Technoeconomic Analyses For Integrated Energy Systems, Anthoney Griffith
All Graduate Theses and Dissertations, Fall 2023 to Present
Technoeconomic analysis is a key element in the study of integrated energy systems. The goal of this analysis is the sizing of technologies resulting in the best economic outcome for the system. The evaluation of this system involves sizing the components and simulating the resulting market to determine an outcome. This simulation incorporates multiple possible values of uncertain parameters like grid price and wind generation. This problem is currently approached with the gradient descent optimization method. An alternative approach, Bayesian optimization, sees success on simple problems of a similar nature to technoeconomic analyses. These results motivate applying Bayesian optimization as …
Development Of A High-Throughput Methodology For Vibration-Based Fatigue Tests, Brandon Alexander Furman
Development Of A High-Throughput Methodology For Vibration-Based Fatigue Tests, Brandon Alexander Furman
All Graduate Theses and Dissertations, Fall 2023 to Present
Global efforts towards the development of additively manufactured materials, biomaterials, metamaterials, self-healing materials, and composites have reached a staggering pace. With new materials being developed on a near-daily basis, it is more important than ever to be able to quickly and precisely quantify their mechanical performance. However, one of the most important mechanical properties, fatigue life, is notoriously time consuming to measure. Consequently, fatigue parameters are often calculated based on small sample sizes, resulting in high uncertainty of the measured parameters. In this dissertation a high-throughput approach to fatigue measurements is developed. This technique allows for multiple samples to accumulate …
Understanding Ion Rejection Mechanism Of Freeze Desalination By Molecular Dynamics Simulation, Mahbuba Jannat
Understanding Ion Rejection Mechanism Of Freeze Desalination By Molecular Dynamics Simulation, Mahbuba Jannat
All Graduate Theses and Dissertations, Fall 2023 to Present
This study explores a method called freeze desalination, which uses the natural process of ice formation to remove salt from water at lower than freezing temperature of water, which is 235K (Freezing temperature of this water model is 249K), making it safe for potable water. Unlike traditional methods, freeze desalination can be more efficient and environmentally friendly, but how it rejects salt at the molecular level is not very clear to understand. Using molecular dynamics simulation, this research aims to uncover the details of this process. We focused on understanding how water molecules interact with salt ions during freezing. Our …
Dynamic Modeling Of A Nuclear Integrated Energy System With Thermal Energy Storage And Hydrogen Production, Seth J. Dana
Dynamic Modeling Of A Nuclear Integrated Energy System With Thermal Energy Storage And Hydrogen Production, Seth J. Dana
All Graduate Theses and Dissertations, Fall 2023 to Present
Historically, nuclear reactors have used water for cooling and moderating the nuclear reaction within the core. Advanced generation IV nuclear reactors currently under development are designed with different coolants which enable operation at higher temperatures. A higher operating temperature makes nuclear power suitable for co-located hydrogen production via high temperature electrolysis. Natrium, an advanced reactor design by TerraPower and GE Hitachi, combines a sodium fast reactor with molten salt thermal energy storage. The work presented in this thesis models and analyzes three Natrium systems which integrate hydrogen production with the Natrium nuclear power plant. The first two configurations focus on …
Trade-Offs In Lighting For Dic Strain Measurements In Vibration-Based Fatigue Testing, Jacob R. Rigby
Trade-Offs In Lighting For Dic Strain Measurements In Vibration-Based Fatigue Testing, Jacob R. Rigby
All Graduate Theses and Dissertations, Fall 2023 to Present
Vibration based fatigue testing offers a fast and efficient method for determining the breaking point of a material. This method often uses a device, called a strain gage, to measure the deformation of a test sample at a single spot on the test sample. However, these strain gages often break before testing is complete. To overcome this premature break, a laser vibrometer is often used to measure the amount of movement or the speed of the test sample throughout the vibration test. The deformation measured by the strain gage is compared against the amount of movement or velocity of the …
Rapid Prediction Of Buoyancy-Driven Exchange Flows At The Great Salt Lake: Ml Models And A 1d Shallow Water Approach, Eric M. Larsen
Rapid Prediction Of Buoyancy-Driven Exchange Flows At The Great Salt Lake: Ml Models And A 1d Shallow Water Approach, Eric M. Larsen
All Graduate Theses and Dissertations, Fall 2023 to Present
The Great Salt Lake in Utah, USA, is a hypersaline terminal lake divided in to northern and southern arms by the Union Pacific Railroad causeway since the 1950's. This separation has caused a difference in density and water surface elevation between lake arms. These differences result in a buoyancy-driven exchange flow occurring through an engineered breach in the causeway. Traditionally, modeling the flow through the breach has been done by numerically solving the 1D steady shallow water equations, and using computational fluid dynamics (CFD). The CFD models yield high accuracy results, but require substantial computing resources. This research proposes the …
Effects Of Periodic Sequential Arrangement Of Subscale Miura-Foldcore Under Quasi-Static Compression, Chase Mortensen, Devin Nielsen, S. Z.H. Shah, Juhyeong Lee
Effects Of Periodic Sequential Arrangement Of Subscale Miura-Foldcore Under Quasi-Static Compression, Chase Mortensen, Devin Nielsen, S. Z.H. Shah, Juhyeong Lee
Mechanical and Aerospace Engineering Faculty Publications
This study presents experimental and numerical investigations on the quasi-static compressive responses of various subscale Miura-foldcore composites. A series of quasi-static compression tests were conducted on standard Miura foldcore specimens fabricated using carbon/epoxy woven fabric prepregs. Representative volume element (RVE) models, incorporating periodic boundary conditions (PBCs), were developed to predict the size-dependent compressive response of subscale Miura foldcores. The effective properties of the carbon/epoxy woven fabric composite used in this study were calculated using the NASA multiscale analysis tool (NASMAT) via two-step homogenization process. The FE model exhibited comparable agreement with experimental results, showcasing variations of less than 7% and …
Impact Of Polymer Structure In Polyurethane Topcoats On Anti-Icing Properties, Donghyeon Lee, Junho Park, Min Ji Woo, Juhyeong Lee, Joung-Man Park, Hyung Mi Lim, Tae Kyung Lee, Seong Baek Yang, Sang Yong Nam, Dong-Jun Kwon
Impact Of Polymer Structure In Polyurethane Topcoats On Anti-Icing Properties, Donghyeon Lee, Junho Park, Min Ji Woo, Juhyeong Lee, Joung-Man Park, Hyung Mi Lim, Tae Kyung Lee, Seong Baek Yang, Sang Yong Nam, Dong-Jun Kwon
Mechanical and Aerospace Engineering Faculty Publications
Icing on the topcoat layer of structures or mobility systems can be a factor leading to functional failures or accidents. Material engineering approach to prevent icing involves creating hydrophobic surfaces. In this study, it was confirmed that the method of controlling the structure of polymers using solvents to adjust surface hydrophobicity and ice prevention effects is effective. Polyurethane (PU) topcoats are primarily used on the exterior of mobility devices; therefore, structure of PU was manipulated using xylene. Through the adjustment of the ratio between PU and xylene, changes in the curing enthalpy and crystal structure were observed, which led to …