Aerospace Engineering Commons^™

A Comprehensive Investigation Of The Influence Of Geometric Structure On The Shape Memory Performance Of Nafion, Jade Thomas

Physics Undergraduate Honors Theses

While perfluorosulfonic acid (PFSA) membranes have primarily been used in fuel cells due to their chemical, thermal, and mechanical stability, one PFSA, Nafion, boasts two unique characteristics: a broad glass transition (~55 °C to 130 °C) and a temperature-persistent electrostatic network. The combination of these two characteristics endows Nafion with exceptional shape memory properties – the ability of a material to morph and transform into pre-programmed shapes when exposed to an external stimulus – with enhanced permanent shape memorization, and a potentially near-infinite number of temporary shape memorization. This study focused on expanding the base of knowledge surrounding Nafion’s shape …

A Comprehensive Investigation Of The Influence Of Geometric Structure On The Shape Memory Performance Of Nafion, Jade Thomas

Mechanical Engineering Undergraduate Honors Theses

While perfluorosulfonic acid (PFSA) membranes have primarily been used in fuel cells due to their chemical, thermal, and mechanical stability, one PFSA, Nafion, boasts two unique characteristics: a broad glass transition (~55 °C to 130 °C) and a temperature-persistent electrostatic network. The combination of these two characteristics endows Nafion with exceptional shape memory properties – the ability of a material to morph and transform into pre-programmed shapes when exposed to an external stimulus – with enhanced permanent shape memorization, and a potentially near-infinite number of temporary shape memorization. This study focused on expanding the base of knowledge surrounding Nafion’s shape …

Principles And Practices For Creating Inherently Resilient Smallsats Despite Constrained Resources, Lee Jasper, Tyler De Caussin

Space Dynamics Laboratory Publications

Over the past few years, small satellites have become heavily utilized for both constellations and single vehicle missions. Many organizations have learned how to be successful with these platforms however, while small, they are not simple systems and first-time creators of these systems still suffer high rates of failure. AFRL's Small Satellite Portfolio has established guiding practices/principles for satellite design that help reduce overall mission risk based upon both community and internal lessons learned. These principles help make the design technically resilient and can also help with programmatic execution. This paper will discuss the principles with some detail (such as …

Numerical Investigation Of Supersonic Flow Over A Wedge By Solving 2d Euler Equations Utilizing The Steger–Warming Flux Vector Splitting (Fvs) Scheme, Mitch Wolff, Hashim H. Abada, Hussein Awad Kurdi Awad Kurdi Saad

Mechanical and Materials Engineering Faculty Publications

Supersonic flow over a half-angle wedge (θ = 15°) with an upstream Mach number of 2.0 was investigated using 2D Euler equations where sea level conditions were considered. The investigation employed the Steger–Warming flux vector splitting (FVS) method executed in MATLAB 9.13.0 (R2022b) software. The study involved a meticulous comparison between theoretical calculations and numerical results. Particularly, the research emphasized the angle of oblique shock and downstream flow properties. A substantial iteration count of 2000 iteratively refined the outcomes, underscoring the role of advanced computational resources. Validation and comparative assessment were conducted to elucidate the superiority of the Steger–Warming flux …

Rasc-Al Large Scale Lunar Crater Prospector, Austin Arnold, Coleman Alvarez, Mark Suberu

Senior Design Project For Engineers

The purpose of this project is to design a conceptual layout of a lunar rover capable of exploring craters at the lunar south pole. The rover should be autonomous and capable of self-sustainment for at least one year in extreme cold and darkness. While determining the location and accessibility of water ice and other volatiles within the crater. This document will contain all information related to the team's conceptual design. Including research, component selection, electrical design, and mechanical design.

Lunar Rascals Video: https://www.youtube.com/watch?v=MdcjzVMtzaI

Using Convolutional Neural Networks For Autonomous Drone Navigation, Joshua Jowers

Industrial Engineering Undergraduate Honors Theses

Unmanned Aerial Vehicles (UAVs), more commonly known as drones, serve various purposes, notably in military applications. Consequently, there arises a need for navigation methods impervious to intercepted signals [1]. Previous research has explored numerous solutions, including machine learning. This paper delves into a specific machine learning approach employing a Convolutional Neural Network (CNN) to discern image locations [2]. It elucidates the conversion of a CNN model between two machine learning libraries and presents results from multiple experiments examining parameters and factors influencing the approach's efficacy. These experiments encompass testing different data sources, image quantities, and processing pipelines to gauge their …

Rapid Response Satellite Launcher, Nathan Jones, Joey Cosentino, Jayson Layton, Afek Adar

Senior Design Project For Engineers

Air launch to orbit is a new style or spacecraft where rockets are attached to a large aircraft and released at cruising altitude to then ignite and launch into space. Companies such as Virgin Orbit are using it as a cheap and efficient way to move satellite payloads into lower or upper Earth orbit. These styles of launchers can be designed to be much smaller than ground-launched spacecraft, reducing cost and weight of the launcher in comparison. With many private companies coming into the space and satellite industry, the design and manufacturing of these launchers have become a focus within …

Towing Tank Trials Of Hydrokinetic Turbine Scale Model To Support Marine Energy System Verification, Shahab Rouhi

LSU New Orleans Theses and Dissertations

In response to the escalating demand for sustainable energy solutions and the critical reevaluation of conventional fossil fuels due to environmental concerns, this dissertation embarks on a comprehensive exploration of hydrokinetic energy as a promising alternative. The study delves into the underexplored domain of hydrokinetic energy, leveraging innovative methodologies for effective utilization and harnessing, particularly through the development and investigation of hydrokinetic turbines.

In the realm of hydrokinetic energy conversion, our research has exclusively concentrated on horizontal-axis turbines, distinct from other turbine configurations. Noteworthy is the adaptation of a conventional horizontal-axis wind turbine for water currents, revealing enhanced performance through …

Effects Of Process-Induced Defects On The Corrosion Of Additively Manufactured Stainless Steel 304l, Leila Saberi, Frank W. Liou, Mehdi Amiri

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This Study Investigates the Impact of Process-Induced Defects Such as Gas Pores, Lack of Fusions, and Surface Roughness on Corrosion Behavior of Stainless Steel 304L (SS304L) Fabricated by Laser Powder Bed Fusion Additive Manufacturing. Specimens Are Printed with Optimized Process Parameters but Selected from Different Locations on the Build Plate. Parallel and Perpendicular Surfaces to the Build Direction Are Investigated and Compared with Corrosion Properties of Wrought SS304L in 5 Wt% NaCl. the Results Reveal Significant Difference in Corrosion Behavior among Specimens Due to Variations in their Defect Features. Pitting Potential, Pit Initiation, and Growth Rates Are Found to Be …

Investigation On The Effects Of Biofouling On The Boundary Layer, Adam N. Bacon

LSU New Orleans Theses and Dissertations

This study is an investigation of the effect of biofouling on the boundary layer of a flat plate and a NACA 4-digit series foil. Three identical hydrofoils made of resin were placed in the Gulf of Mexico at Grand Isle, Louisiana, and observed and analyzed by marine biologists at the University of New Orleans for their species composition. The resulting biofouling that grew was primarily made up of barnacles and bryozoans. The foils were submerged in an open channel flume at zero incidence and subjected to a series of experiments whose arc-length Reynolds numbers ranged from approximately 13000 to 32000. …

A Study Of Varying Dielectric Constant And Thickness Of Dielectric Barrier Discharge Devices And Their Subsequent Plasma Actuation, Sharon Kardasz

Mechanical Engineering Undergraduate Honors Theses

The principles of air-breathing ion propulsion are relatively unestablished in the aerodynamic realm as traditional forms of combustion for propulsion systems have remained in use. However, due to increasing environmental, economic, and efficiency concerns of traditional combustion, interests in innovative propulsion methodologies, such as electric propulsion, are emerging. A primary technology of interest for use of ion propulsion is the Dielectric Barrier Discharge Device (DBD). Preliminary research conducted at the University of Arkansas has determined the most favorable DBD geometry. This work will continue the preliminary research to decipher the most favorable DBD configuration by varying dielectric thickness and dielectric …

Cosmic Object Space Management Operations System (C.O.S.M.O.S.), Riah Ivy, Tyler Bumpus, Gabriel Soter

Senior Design Project For Engineers

In the expansive realm of outer space, humanity has ventured into new territories, yet this progress is accompanied by challenges. Among the most significant challenges confronting space exploration today is the growing amount of space debris within low earth orbit. Satellites, spent rocket stages, and assorted fragments orbiting Earth present a considerable hazard to spacecraft and astronauts, and this issue is steadily worsening. For years, the task of remedying this orbital congestion has remained formidable and unresolved. This design provides a novel and innovative solution to this growing problem.

Meta Project: Construction, Validation, And Flight Testing Of A New Meta Aircraft Design, William Andrew Wearren

Honors Theses

Meta aircraft are a type of aircraft that can connect via wingtip, nose-to-tail, or both wingtip and nose-to-tail in order to create a lattice of aircraft that can fly together to a site, detach, survey different areas, and then reattach for flight back to the main base. The project started at the Georgia Institute of Technology with Dr. Carlos Montalvo and is being continued at the University of South Alabama Facility for Aerospace Systems and Technology Lab. This paper seeks to theoretically verify the new aircraft design for the META project, complete the development of the design, and to experimentally …

Oxider To Fuel Ratio Shift Compensation Via Vortex Strength Control In Hybrid Rocket Motors, Max W. Francom

All Graduate Theses and Dissertations, Fall 2023 to Present

Hybrid motors have existed as a hypothetical propulsion system for decades in a wide range of upper stage rocket motors due to their simple, robust, non-toxic, and versatile nature. However, inherent to hybrids is Oxidizer to Fuel ratio (O/F) shift over time, which results in performance losses for the majority of the rocket’s lifetime. The purpose of this study is to develop a hybrid rocket motor capable of manipulating O/F at will, resulting in an engine which eliminates the undesirable effects of O/F shift. By developing and refining a numerical simulation, a novel injector system, and an open-loop control scheme, …

Transfer-Learning-Enhanced Regression Generative Adversarial Networks For Optimal Evtol Takeoff Trajectory Prediction, Shuan Tai Yeh, Xiaosong Du

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Electric vertical takeoff and landing (eVTOL) aircraft represent a crucial aviation technology to transform future transportation systems. The unique characteristics of eVTOL aircraft include reduced noise, low pollutant emission, efficient operating cost, and flexible maneuverability, which in the meantime pose critical challenges to advanced power retention techniques. Thus, optimal takeoff trajectory design is essential due to immense power demands during eVTOL takeoffs. Conventional design optimizations, however, adopt high-fidelity simulation models in an iterative manner resulting in a computationally intensive mechanism. In this work, we implement a surrogate-enabled inverse mapping optimization architecture, i.e., directly predicting optimal designs from design requirements (including …

Development, Modeling, Identification, And Control Of Tilt-Rotor Evtol Aircraft, Clayton T. Spencer

All Graduate Theses and Dissertations, Fall 2023 to Present

This thesis includes the development, modeling, identification, and control of an electric-Vertical-Take-Off-and-Landing (eVTOL) aircraft with tiltable rotors. The front two rotors have tilting capability for transition flight from vertical-take-off to forward-level flight. This work details the development of an eVTOL aircraft and the selection of sub components such as electric motors, batteries, and controllers. After the aircraft build, mathematical model is derived to describe the motion of the aircraft. Unknown parameters in the mathematical model are identified using a Least-Squares-regression (LSR) method that can handle parameter constraints. This is done using real flight data collected from the aircraft. Lastly, this …

An Investigation Into In-Flight Loss Of Control Accidents Due To Horizontal Stabilizer Changes On The Piper Cherokee, Connor John Geran

Theses and Dissertations

Loss of Control (LOC) while in-flight in General Aviation (GA) has been the subject of intense research by academic institutions and regulatory agencies in recent years [4] [9] [11] [19] [20] [21]. This interest is primarily due to a disproportionate number of all aircraft accidents occurring within the GA category of flight, with 94% of accidents in 2022 occurring within GA, caused primarily by pilot LOC, with 42% of accidents having LOC as the listed cause. Research into this subject at FIT yielded the results that many common GA aircraft tend to experience a strong pitch up response after undergoing …

Relations Between Printability And Rheology In A Ceramic Paste Extrusion Process, Nicholas Durand

Open Access Theses & Dissertations

Ceramic additive manufacturing (AM) uses the same fundamentals as material extrusion (MEX) that utilizes polymers or resins for printing applications. Ceramic AM uses the same process of slicing an STL file to determine a toolpath for the printer that will facilitate material deposition to manufacture full parts; ceramic AM also provides a low-cost advantage when compared to processes that require high powered lasers for melting metal powders or heated nozzles used for dispensing thermoplastics. Despite having the similar design freedom and ability for rapid prototyping that other printing methods benefit from with the addition of low cost, ceramic AM has …

Analysis Of Additively Manufactured Inconel 718 Combustion Behavior In Promoted Oxygen Environments, Dominic George Dieguez

Open Access Theses & Dissertations

Promoted combustion testing is a vital tool for engineers to establish the combustion and flammability characteristics of materials (metallic or otherwise) in oxygen enriched environments. Historically, much of the established data for metallic promoted combustion has been with regards to materials in their cast and wrought forms. However, with the emergence of additive manufacturing as a preferred method of fabrication, the need exists to evaluate how metals in that form behave. Recent testing has demonstrated that even if a metal or alloy is nominally the same with regards to chemistry, flammability between samples in the wrought form can differ significantly …

Numerical Simulations Of Supersonic/ Hypersonic Flows In Compression Corners And A Hypersonic Flow Study Of Atmospheric Entry Of Mars Science Laboratory Capsule, Dexter Allen

McKelvey School of Engineering Graduate Student Theses & Dissertations

This thesis consists of two related parts. The first part is the study of supersonic/hypersonic flow in compression corners. The compression corners are simple geometries but rich in flow-features that can be challenging for accurate prediction of their flow fields in high-speed compressible flow using the Reynold-Averaged Navier-Stokes (RANS) equations in conjunction with a turbulence model. At higher degrees of corner angles, there exists a shock-boundary layer interaction region which includes a significant recirculation zone in the corner. In this thesis, experimentally available test cases for compression corner at Mach 3, 8, and 11 at various corner angles are modeled …