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Full-Text Articles in Engineering

Study Of A Carbon Fiber Reinforced Polymer Composite Using A Biobased Polyurethane As A Thermosetting Resin, Teddy Mageto May 2023

Study Of A Carbon Fiber Reinforced Polymer Composite Using A Biobased Polyurethane As A Thermosetting Resin, Teddy Mageto

Electronic Theses & Dissertations

Carbon Fiber Reinforced Polymer composites (CFRP) have garnered increasing interest in recent years especially in the aerospace and automobile industries where they are gradually replacing metals as structural materials. This is owing to their light weight, high strength, high modulus, and excellent strength-to-weight ratio. Polymers are typically used as thermosetting resins in these composites. However, the synthesis of polymers currently is conducted via petrochemical processes which leads to adverse effects on the environment. To this end, in this work a biobased Polyurethane (PU) was used as a thermosetting resin in a CFRP. The biobased PU was synthesized by the reaction …


The Effects Of Differing Light Wavelengths And Gravity On, Reese Chesshir May 2023

The Effects Of Differing Light Wavelengths And Gravity On, Reese Chesshir

Honors Theses

Physarum is a slime mold in the class of Mycetozoan and the family of Physaraceae. It is a single cellular, multinuclear organism that is not classified as an animal, plant, or fungi. Physarum growth for long-term space travel would be beneficial because it is a decomposer and is able to break down material and waste to recycle. This is important for transferring energy and allowing other organisms to grow. The purpose of this experiment is to study the effect of different light wavelengths and the influence of gravity on Physarum growth patterns.


Computational Analysis Of Steady Hypersonic Flow Fields Of Nasa Benchmark Geometries Utilizing Ansys Fluent, Aidan Murphy May 2023

Computational Analysis Of Steady Hypersonic Flow Fields Of Nasa Benchmark Geometries Utilizing Ansys Fluent, Aidan Murphy

McKelvey School of Engineering Theses & Dissertations

The Hypersonic International Flight Research Experimentation (HIFiRE) program explores and advances hypersonic aerospace systems by developing a multitude of test flight geometries and conducting experimental test flights to obtain data for use in validation of computational models and results. This study focuses on computational validation of heat flux, and calculation of static pressure profiles, skin friction coefficient profiles, and flow contours. The flow fields studied are for Mach number 7.18 and angles of attack (α) of 0° & 2°. These flow fields include many compressible flow features such as an expansion wave at the intersection of the cone and flat …


An Online Adaptive Machine Learning Framework For Autonomous Fault Detection, Nolan Coulter May 2023

An Online Adaptive Machine Learning Framework For Autonomous Fault Detection, Nolan Coulter

Doctoral Dissertations and Master's Theses

The increasing complexity and autonomy of modern systems, particularly in the aerospace industry, demand robust and adaptive fault detection and health management solutions. The development of a data-driven fault detection system that can adapt to varying conditions and system changes is critical to the performance, safety, and reliability of these systems. This dissertation presents a novel fault detection approach based on the integration of the artificial immune system (AIS) paradigm and Online Support Vector Machines (OSVM). Together, these algorithms create the Artificial Immune System augemented Online Support Vector Machine (AISOSVM).

The AISOSVM framework combines the strengths of the AIS and …


Online Estimation Of Unknown Parameters For Flexible Spacecraft, Nicolo Woodward May 2023

Online Estimation Of Unknown Parameters For Flexible Spacecraft, Nicolo Woodward

Doctoral Dissertations and Master's Theses

Attitude controls methods of highly flexible spacecraft have seen increased interest over the last decades thanks to the technological development of flexible solar panels and deploy-ables, which improves the capabilities of small satellites. However, a high-fidelity model of the flexible mode dynamics is hard to obtain in on-ground testing because not all modes of frequencies can be observed, complicating the controller design. Furthermore, plastic deformations due to long periods of storage of stowed flexible components could result in exciting frequencies outside of the designed controller’s bandwidth, leading to an uncontrollable system. This thesis proposes a method to develop a high-fidelity …


Sensor Module Network For Monitoring Trace Gases In The International Space Station, Aaron Beck, Drake Provost, Christopher English, Kamrin Gustave May 2023

Sensor Module Network For Monitoring Trace Gases In The International Space Station, Aaron Beck, Drake Provost, Christopher English, Kamrin Gustave

Honors Capstones

The Jet Propulsion Laboratory (JPL) of the National Aeronautics and Space Administration (NASA) aims to develop a sensor network for the International Space Station (ISS) to ensure a comprehensive understanding of air quality within the station. The accumulation of carbon dioxide (CO­­­­­2) can lead to cognitive impairment, headaches, and potentially dangerous situations at high concentrations. Monitoring air content at the ISS is critical to maintaining a healthy environment for crew onboard. Exposure to harmful gases causes negative side effects that make crew sick, which may interfere with their responsibilities. CO2 is a gas that should be monitored …


Feasibility Of Thermoplastic Extrusion Welding As A Joining Method For Vacuum-Assisted Additively Manufactured Tooling, Chase C. Flaherty May 2023

Feasibility Of Thermoplastic Extrusion Welding As A Joining Method For Vacuum-Assisted Additively Manufactured Tooling, Chase C. Flaherty

Electronic Theses and Dissertations

In recent years, additive manufacturing (AM) has been successfully utilized for the production of large-scale composite tooling. Within these endeavors, however, limited research has focused on joining methods between printed sections. This work evaluates the feasibility of thermoplastic extrusion welding as a joining method for additively manufactured tooling structures. This joining method was assessed based on industry specifications of conventional thermoset tooling for wind blade manufacturing utilizing the vacuum-assisted resin transfer molding (VARTM) process. The specifications include requirements for the mechanical strength, vacuum integrity, roughness, and hardness of the tool surface. The feasibility of this welded polymer joint was demonstrated …


Investigation Into Sintered Lunar Regolith Construction Methods And Novel Usability Evaluation, Thomas A. Cox May 2023

Investigation Into Sintered Lunar Regolith Construction Methods And Novel Usability Evaluation, Thomas A. Cox

Electronic Theses and Dissertations

Since the Apollo missions in the late 1960's, there has been a growing interest shared by many countries around the world to return to the Moon and establish a permanent Lunar settlement. The first phase of temporary Lunar bases will be established over the next several years. For a permanent human presence on the Moon, it will be necessary to use locally available resources for the construction of Lunar habitats and other infrastructure. Sintering Lunar regolith has been shown to be a promising method for producing structural material with a variety of desirable properties from strength to radiation shielding. While …


Simulating Condensation In The Theory Of Classical Nucleation, David Vallet May 2023

Simulating Condensation In The Theory Of Classical Nucleation, David Vallet

UNLV Theses, Dissertations, Professional Papers, and Capstones

The scope of this thesis is to numerically investigate condensation that occurs in transonic and supersonic flows. Condensation shocks are a phenomenon that occurs within converging-diverging nozzles. There are many applications forconverging-diverging nozzles, such as thermovapour compressors (TVC), which are largely used for desalination. As water resources become more precious within the western United States there is a need to develop cost effective solutions for cleaning water. Steam generator power stations are another application where enhanced simulations and accuracy of design could improve efficiency and save on carbon emissions. Traditionally, numerical designs of transonic flows have been conducted with either …


Study Of Different Heat Treatments And Aging Conditions For Observing Microstructures And Mechanical Properties Of Lpbf Fabricated F357 Alloy, Victor Adrian Medrano Balderas May 2023

Study Of Different Heat Treatments And Aging Conditions For Observing Microstructures And Mechanical Properties Of Lpbf Fabricated F357 Alloy, Victor Adrian Medrano Balderas

Open Access Theses & Dissertations

Aluminum F357 is a widely used material for casting in the aerospace and additive manufacturing industry. Heat treatments are commonly applied to some aluminum alloys to modify their properties. With a further study on the aging and performance of the F357 with 3D printing technology, several industries benefit from this; military, automotive, and aerospace are some examples because of the numerous components cast in service. This work presents the mechanical properties of F357 specimens fabricated with EOS technology and subjected to heat treatments. Heat treatment conditions were applied to tensile specimens and tested. Furthermore, the specimens were subjected to artificial …


Classification Of Electrical Current Used In Electroplastic Forming, Tyler Grimm May 2023

Classification Of Electrical Current Used In Electroplastic Forming, Tyler Grimm

All Dissertations

Electrically assisted manufacturing (EAM) is the direct application of an electric current to a workpiece during manufacturing. This advanced manufacturing process has been shown to produce anomalous effects which extend beyond the current state of modeling of thermal influences. These purported non-thermal effects have collectively been termed electroplastic effects (EPEs).

While there is a distinct difference in results between steady-state (ideal DC) testing and pulsed current testing, the very definition of these two EAM methods has not been well established. A "long" pulse may be considered DC current; a "short" pulse may produce electroplastic effects; and even "steady-state" current shapes …


An Experimental Investigation Of The Effect Of Narrowband Freestream Noise On Fundamental Transitional Shockwave-Boundary Layer Interaction Mechanisms, Zane Matthew Shoppell May 2023

An Experimental Investigation Of The Effect Of Narrowband Freestream Noise On Fundamental Transitional Shockwave-Boundary Layer Interaction Mechanisms, Zane Matthew Shoppell

Masters Theses

Recent work at the University of Tennessee Space Institute has demonstrated that the resonant behavior observed in the spectra of cylinder- and blunt-fin-generated XSBLIs is connected to fundamental fluid mechanisms within the boundary layer. Therefore, a test campaign was conducted to characterize the fundamental mechanisms that drive the low-frequency unsteadiness in cylinder- and blunt-fin-generated shockwave-boundary layer interactions, specifically shockwave-boundary layer interactions in which the incoming boundary layer is undergoing a laminar-to-turbulent transition. This research aims to develop a deeper understanding of such interactions and characterize the resonant behavior observed in past work by varying the sweepback angle of a hemicylindrical …


Design And Implementation Of High-Efficiency, Lightweight, System-Friendly Solid-State Circuit Breaker, Dehao Qin May 2023

Design And Implementation Of High-Efficiency, Lightweight, System-Friendly Solid-State Circuit Breaker, Dehao Qin

All Dissertations

Direct current (DC) distribution system has shown potential over the alternative current (AC) distribution system in some application scenarios, e.g., electrified transportation, renewable energy, data center, etc. Because of the fast response speed, DC solid-state circuit breaker (SSCB) becomes a promising technology for the future power electronics intensive DC energy system with fault-tolerant capability. First, a thorough literature survey is performed to review the DC-SSCB technology. The key components for DC-SSCB, including power semiconductors, topologies, energy absorption units, and fault detection circuits, are studied. It is observed that the prior studies mainly focus on the basic interruption capability of the …


Simulating Dielectric Barrier Plasma Actuators With Varying Geometries, Cass Wiederkehr May 2023

Simulating Dielectric Barrier Plasma Actuators With Varying Geometries, Cass Wiederkehr

Mechanical Engineering Undergraduate Honors Theses

The idea of Ionic Wind Propulsion has long been a topic of research for whether or not it can be used as a practical power source for flight. MIT researchers proved in 2018 that a plane with zero moving parts powered by Ionic Wind Propulsion was possible, and sustained flight could work with an internal power supply. However, due to the thin wire electrodes required to generate the ion cloud that made such propulsion possible, large amounts of drag rendered the plane extremely inefficient and impractical. Dielectric Barrier Discharge Devices (DBDs) are being investigated as to whether they can serve …


Investigation Of Dynamic Hybrid Rans-Les Turbulence Modeling For Cfd Simulation Of A Normal Jet In Crossflow, Cole Simmonds May 2023

Investigation Of Dynamic Hybrid Rans-Les Turbulence Modeling For Cfd Simulation Of A Normal Jet In Crossflow, Cole Simmonds

Mechanical Engineering Undergraduate Honors Theses

The jet in crossflow is a canonical flow feature in many natural and engineered systems, ranging from pollutant dispersal in exhaust discharge to film cooling of high-temperature components in modern propulsion systems. The ability to computationally predict the flow features of jets in crossflow accurately and efficiently is therefore important for analysis and design for a wide variety of applications. In this study the capabilities of the dynamic hybrid RANS-LES (DHRL) turbulence modeling technique are investigated and compared to an industry standard Reynolds-averaged Navier-Stokes model (k-omega SST) in order to quantify the accuracy and computational cost of the two approaches. …


Fusion Bonding Behavior Of 3d Printed Pa6/Cf Composites Via Post Fabrication Compaction, Gonzalo Fernandez Mediavilla May 2023

Fusion Bonding Behavior Of 3d Printed Pa6/Cf Composites Via Post Fabrication Compaction, Gonzalo Fernandez Mediavilla

Mechanical & Aerospace Engineering Theses & Dissertations

Additive manufacturing (AM) is becoming a robust production technology for aerospace, healthcare, and construction industries among others. Fused Deposition Modelling (FDM) is one of the methods most used to 3D print products. FDM has limitation due to interlayer adhesion and restriction imposed by the printing direction. Specially with AM composites, as reinforced nylon PA6 with short fibers, parts show more strength along the direction of the filament due to the alignment of the carbon fibers, but weaker in other directions. The proposed method to solve this issue is to print parts separately and join them together by fusion bonding. PA6/CF …


Sealion Cubesat Mission Architecture Using Model Based Systems Engineering With A Docs As Code Approach, Kevin Yi-Tzu Chiu May 2023

Sealion Cubesat Mission Architecture Using Model Based Systems Engineering With A Docs As Code Approach, Kevin Yi-Tzu Chiu

Mechanical & Aerospace Engineering Theses & Dissertations

CubeSats are a growing population within the space industry. Every year, universities launch numerous amounts of CubeSats due to their inexpensive cost of development, launch, and deployment. However, this comes with numerous challenges. As the number of university-CubeSats grow, so too do the numbers that fail. With development teams consisting mainly of students with little to no training, proper and yet easy to use tools or methods should be implemented to help ensure mission success. Especially in the critical stages of planning before and during development, a technical approach to quickly track life cycle development of a CubeSat is needed. …


Electrochemical Investigation Of Copperzirconium Based Metallic Glass Cu₅₁Zr₃₀Hf₁₄Ag₅, Tamim Mohammad Ahmad May 2023

Electrochemical Investigation Of Copperzirconium Based Metallic Glass Cu₅₁Zr₃₀Hf₁₄Ag₅, Tamim Mohammad Ahmad

Theses

This thesis is concerned with the electrochemical investigation of the copper-zirconium

based metallic glass Cu51Zr30Hf14Ag5. Studying the corrosion behavior of the novel melt-spun metallic glass ribbons contributes to further research on the possibility of building future bio-implants. The objectives of this thesis are to synthesize the metallic glass ribbons which are free from cytotoxic elements using melt spinning technique, verify their amorphous nature using X-ray diffraction method, study the corrosion behavior using Potentiodynamic polarization and Electrochemical Impedance Spectroscopy in different acidic, neutral and basic solutions, and finally examine the surface morphology of …


Low-Erosion Nozzle Materials For Long-Duration Hybrid Rocket Burns, Russell S. Babb May 2023

Low-Erosion Nozzle Materials For Long-Duration Hybrid Rocket Burns, Russell S. Babb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid rocket systems, which employ a solid fuel grain and a liquid oxidizer, are a low-cost and environmentally friendly alternative to traditional rocket systems. However, hybrid rockets suffer from an increased nozzle throat erosion rate, which impacts motor performance and reliability. To address this issue several materials and low-erosion nozzle configurations were tested. The results of the testing campaign produced a nozzle that reduce the throat erosion rate five-fold.


Augmented State Linear Covariance Applications For Nonlinear Missile Engagements, Jeffrey Scott Clawson May 2023

Augmented State Linear Covariance Applications For Nonlinear Missile Engagements, Jeffrey Scott Clawson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sustained actuator saturation is a common occurrence for missile engagements. The saturation nonlinearity creates some difficulty for high-fidelity linear analysis methods. This dissertation investigates three methods of modeling actuator saturation in an advanced linear analysis. The linear covariance tools from this dissertation run extremely fast and provide several advantages over other linear missile engagement analysis methods. First, a simulation is developed and validated for a target engagement scenario without actuator saturation. Next, saturations are introduced to the problem, along with the first analysis method: statistical linear covariance analysis. This method combines the augmented state linear covariance framework with the statistical …


Aerodynamic Implications Of A Bio‐Inspired Rotating Empennage Design For Control Of A Fighter Aircraft, Christian R. Bolander May 2023

Aerodynamic Implications Of A Bio‐Inspired Rotating Empennage Design For Control Of A Fighter Aircraft, Christian R. Bolander

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation presents an analysis of the aerodynamics for an aircraft using a novel, bio-inspired control system. The control system is a rotating tail, that is inspired by the way in which birds use their tail to control their flight. An aerodynamic model for a baseline aircraft and a bio-inspired variant are created by referencing well-known relationships for the aerodynamics of flight, which are then used to analyze the available flight envelope at which each aircraft can reach two different equilibrium states. An analysis of the total aerodynamic control authority of each aircraft is also included along with a preliminary …


High Efficiency Angles-Only Space-Based Approaches For Geosynchronous Orbit Catalog Maintenance With Sparse Information, Louis M. Tonc May 2023

High Efficiency Angles-Only Space-Based Approaches For Geosynchronous Orbit Catalog Maintenance With Sparse Information, Louis M. Tonc

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The thesis of this dissertation proposes a novel filter algorithm to improve tracking and catalog maintenance of uncooperative satellites and other Resident Space Objects (RSOs) in Geosynchronous Equatorial Orbit (GEO). Tracking can be supported by space-based tracking from observer satellites (OBSs). Practical limitations can lead to long time gaps between measurement updates when tracking RSOs from an OBS, which may induce a loss of fidelity or divergence of the estimation algorithm. The Extended Kalman filter (EKF) is commonly used for tracking RSOs but it diverges as a consequence of nonlinearity in the dynamics and nonlinearity in the optical measurements from …


Investigation Of Interplanetary Trajectories To Sedna, John W. Sarappo Iii, Samuel Brickley, Iliane Domenech, Lorenzo Franceschetti, James E. Lyne May 2023

Investigation Of Interplanetary Trajectories To Sedna, John W. Sarappo Iii, Samuel Brickley, Iliane Domenech, Lorenzo Franceschetti, James E. Lyne

Chancellor’s Honors Program Projects

No abstract provided.


A Systematic Study Into The Design And Utilization Of Burn Wire As A Means Of Tensioning And Releasing Spacecraft Mechanisms Through Applied Joule Heating, Chandler Dye May 2023

A Systematic Study Into The Design And Utilization Of Burn Wire As A Means Of Tensioning And Releasing Spacecraft Mechanisms Through Applied Joule Heating, Chandler Dye

Mechanical Engineering Undergraduate Honors Theses

The joule heating characteristics of Nichrome burn wires, often used as a thermal cutting device in mechanisms designed to fasten and release CubeSat deployables, are examined in the following thesis. Wires ranging from 0.125 inches to 2 inches long, and diameters of 30 Ga and 40 Ga, are investigated through analytical calculations and thermal simulations based on heat transfer due to joule heating, and through physical circuitry-based experiments. The temperature data is used to generate heating curves to predict the time it takes for Nichrome wires to fail under varying testing parameters. This research aims to catalog a series of …


Accident Investigation On In-Flight Loss Of Control Due To Configuration Change On Piper Arrow, Basilio Caruso May 2023

Accident Investigation On In-Flight Loss Of Control Due To Configuration Change On Piper Arrow, Basilio Caruso

Theses and Dissertations

Between 2012 and 2021, NTSB has identified over 2200 accidents due to loss of control. The majority of which happened while flying in the pattern. The most challenging phase of a flight is the take-off and landing. During these phases, the pilot initiates a change of configuration of the airplane by lowering or retracting the flaps. Lowering the flaps slows down the plane and increases the lift of the wing but also changes the longitudinal free response of the aircraft. The pitch changes of the plane require the pilot to promptly compensate to keep straight and level flight and avoid …


Flight Test Evaluation Of The B-1b Lancer For The Heavy Bomber Mission, Robert William Gates May 2023

Flight Test Evaluation Of The B-1b Lancer For The Heavy Bomber Mission, Robert William Gates

Theses and Dissertations

Copyright held by author


Enabling Premixed Hydrogen-Air Combustion For Aeroengines Via Laboratory Experiment Modeling, Christopher James Caulfield May 2023

Enabling Premixed Hydrogen-Air Combustion For Aeroengines Via Laboratory Experiment Modeling, Christopher James Caulfield

Masters Theses

All combustion systems from large scale power plants to the engines of cars to gas turbines in aircraft are looking for new fuel sources. Recently, clean energy for aviation has come into the foreground as an important issue due to the environment impacts of current combustion methods and fuels used. The aircraft industry is looking towards hydrogen as a new, powerful, and clean fuel of the future. However there are several engineering and scientific challenges to overcome before hydrogen can be deployed into the industry. These issues
range from storing the hydrogen in a viable cryogenic form for an aircraft …


Determining Performance Characteristics From The Mississippi Cowling - Piper Warrior Vs. Piper Archer, Soufiane Ait Yahia May 2023

Determining Performance Characteristics From The Mississippi Cowling - Piper Warrior Vs. Piper Archer, Soufiane Ait Yahia

Theses and Dissertations

Today, Piper is one of the most used aircraft in the general aviation sector. The history of Piper Aircraft has been the subject of numerous books and research projects with over 80 years of aviation industry leadership. For aviation fanatics, the Cherokee is synonymous with Piper Aircraft Corporation. The Piper PA-28 Cherokee is a family of two-seat or four-seat light aircraft built for air taxi, flight training, and personal use. The original Piper Cherokees PA-28- 150 and PA-28-160 received their type certificate from the Federal Aviation Administration back in 1960 and the series remains in production to this day. Multiple …


A Study To Determine Performance Characteristics Of The Mississippi Cowling - Piper Archer Vs. Piper Warrior, Zilvinas Visockas May 2023

A Study To Determine Performance Characteristics Of The Mississippi Cowling - Piper Archer Vs. Piper Warrior, Zilvinas Visockas

Theses and Dissertations

Today, aviation is one of the most technologically advanced and innovative sectors in the world. With fast-depleting natural resources, increasing environmental pollution, and continuous growth in fuel cost, efficiency has become industry’s top priority. Engineers are making gradual improvements that offer overall increase in aircraft’s performance. Drag is critical factor in aviation as it directly impacts aircraft’s fuel efficiency, range, and speed. During the design phase, engineers invest significant effort and expense in attempting to minimize the drag profile by implementing aerodynamic shapes and constantly reducing component weights. One of the real-life examples of such engineering attempts is Piper Archer, …


Climb Performance Testing Of The Pa-28-180 Utilizing Saw-Tooth Method And Level Acceleration Method, Paige Elizabeth Christensen May 2023

Climb Performance Testing Of The Pa-28-180 Utilizing Saw-Tooth Method And Level Acceleration Method, Paige Elizabeth Christensen

Theses and Dissertations

This thesis details the test methods, data reduction methods, and flight data analysis conducted in the climb performance evaluation of the PA-28-180 “Piper Arrow.” The main objective of this thesis was to quantitatively compare the climb performance requirements detailed in the former regulation, CAR 3.85a to the current regulation, 14 CFR 23.2120, utilizing Saw-Tooth steady climb method conducted at various airspeeds. The report also evaluates the Level Acceleration method at reciprocating headings, and qualitatively assesses the usefulness of testing multiple headings on a general aviation aircraft at multiple altitudes. The Saw-Tooth Climb and Level Acceleration flights were conducted on January …