Aerospace Engineering Commons^™

Low Earth Orbit Drag Sail Degradation Due To Atomic Oxygen And Ultraviolet Radiation, Hannah Rost

Master's Theses

As the orbital debris population increases, so does the risk of collisions with operational spacecraft. In response, the Federal Communications Commission has shortened the deorbit requirement from 25 years to five years. While natural atmospheric decay was sufficient under the previous guideline, many objects with low area to mass ratios can no longer passively comply. Smaller, non-propellant-carrying space objects such as CubeSats lack the ability to maneuver and must rely on alternative deorbit methods. One proposed solution is to deploy a drag sail at end of life to increase atmospheric drag and accelerate orbital decay. However, exposure to atomic oxygen …

Model-Based Design Of Compressed Lithium-Metal Pouch Cell Battery Modules For Evtol Applications, Scott J. Stirling

Master's Theses

Batteries with higher specific energy and power are essential for extending the range and performance of electric vertical takeoff and landing aircraft (eVTOLs). Anode-free lithium-metal pouch cells offer strong potential at the cell-level but require high compressive pressures to enhance cycle life and discharge performance. These pressures necessitate heavier structural components, reducing packaging efficiency at the module level.

To evaluate this tradeoff, a full-factorial enumeration model was developed to explore viable module designs within a constrained packaging volume. The model scales subsystem masses, enforces design rules and material limits, and accounts for large (~20%) cell thickness changes during cycling.

Results …

3d Printed Fixed Wing Aircraft Competition, Sidney E. Long, Mitchell Heise, Jack Bride, Daniel Salinas

Mechanical Engineering

Cal State LA and Arlington University, Texas are hosting the same 3D printed, fixed wing aircraft competition for 2025. Cal Poly requires a competitive plane that can adhere to each rule and be piloted remotely to achieve the longest time in the air. The plane must utilize solely 3D printing technology for the wings, body, and all other structures. The only off-the-shelf components can be the motor and electronics, as well as mechanical devices such as hinges.

Ultrafast Laser Surface Structuring For Wettability Control On Copper, Akshay Arvind Nagvenkar

All Theses

Wettability is a crucial surface property influencing various phenomena, including heat transfer, cell adhesion, and corrosion. Engineering devices can achieve superior performance by precisely manipulating surface wettability. As a result, extensive research has focused on developing surfaces that exhibit either extreme water attraction (superhydrophilic) or strong water repellency (superhydrophobic). Tailoring surface wettability paves the way for numerous applications, such as drag reduction in marine vessels, controlled drug delivery, efficient water collection, advanced liquid transport systems, oil-water separation, anti-corrosion coatings, friction reduction, and self-cleaning materials. Ultrafast laser surface structuring is a promising approach for engineering multifunctional surfaces, effectively modifying material properties …

Characterizing Heating And Resistance Properties Of Nichrome Burn Wire To Be Used In Cubesat Actuation, Noah Moix

Mechanical Engineering Undergraduate Honors Theses

This thesis investigates the use of Nichrome 60 wire as a burn wire mechanism, commonly utilized in CubeSats and other aerospace engineering applications requiring precise, single-use release systems. The experiment focused on characterizing the thermal and resistive behavior of Nichrome 60 wire under Joule heating conditions. Four wire configurations were tested: 34-gauge and 36-gauge wires, each at lengths of 1 inch and 2 inches. Each configuration was subjected to a constant current until thermal failure occurred. During testing, real-time measurements of electrical resistance and wire temperature were recorded. This data was used to generate resistance vs. temperature profiles for each …

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. …

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 …

Fabrication Of Ultra High-Temperature Compact Heat Exchanger By Extrusion-Based Ceramic Additive Manufacturing, Abid Hasan Rafi, David W. Lipke, Jeremy Lee Watts, Greg Hilmas, Ming-Chuan Leu

Miners Solving for Tomorrow Research Conference

No abstract provided.

Additive Manufacturing Of Thermoplastic Composites, Matik Heskin, K. Chandrashekhara, Richard Billo, Ming-Chuan Leu, Thomas P. Schuman

Miners Solving for Tomorrow Research Conference

No abstract provided.

Graphene-Polymer Nanocomposite For Electromagnetic Interference Shielding, Ravi Venkata Surya Sai Mogilisetti

Mechanical and Aerospace Engineering Theses - Archive

Polymers have widespread usage in most industries, such as aerospace, automotive, telecommunications, and medicine, mainly because they have a positive lightweight nature and excellent mechanical properties. One significant advantage of polymeric materials is their ability to combine nano-fillers, greatly enhancing their mechanical, electrical, and thermal properties. In the category of polymer matrices, polypropylene (PP) is notable for its low cost, ease of processing, and balanced mechanical properties. However, its relatively lower modulus and strength limit their applications in high-performance engineering. This research explores the addition of graphene into polypropylene to improve its mechanical properties and establish a conductive network for …

Mitigating Out-Of-Plane Fiber Waviness In Afp Laminates With Tow-Gaps Via Selective Placement Of Thermoplastic Veils, Ahmadreza Ravangard, Kuthan Celebi, Sergii G. Kravchenko, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

Fiber tow-gaps and overlaps formed during the Automated Fiber Placement (AFP) process pose a significant challenge by introducing non-uniform composite morphologies, often characterized by resin-rich regions and fiber waviness. These defects occur as deposited fibers sink into the gap regions during consolidation, with gap geometry determined during path planning. Such morphological inconsistencies can compromise structural reliability by initiating premature failure, particularly through localized out-of-plane waviness and resin accumulation. This study investigates the integration of high melting temperature thermoplastic veils, specifically polyetherimide (PEI), into fiber tow-gaps as a method to prevent ply sinking and reduce fiber waviness on both internal and …

Ground Testing Of A Magnetic-Electrostatic Separation System For Lunar Regolith Beneficiation, Peter Bachle, Charles Wood, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Materials Science and Engineering Faculty Research & Creative Works

The separation of lunar regolith by mineral composition and size category is useful forin-situ resource utilization (ISRU). The research presented herein discusses the designing and development of equipment that has the potential to separate lunar regolith into aluminum, iron-titanium, and magnesium-iron ores. Along with the metal ore separation, this equipment shows the potential to separate regolith by size categories. The combined effect of these separation methods generates output that is valuable to subsequent use in metal and oxygen extraction, additive manufacturing, and regolith sintering processes. The designed equipment uses a dual-strength magnet system with N42 and N52 neodymium magnets for …

Mechanical And Thermal Characterization Of Additively Manufactured Carbon/Nylon 12 And Carbon/Peek Composites, Matik Heskin, Bradley Deuser, Thomas P. Schuman, K. Chandrashekhara, John Bayldon, Jeff Degrange, Steven Patterson, Neiko Levenhagen

Chemistry Faculty Research & Creative Works

This study explores additive manufacturing of carbon fiber-reinforced thermoplastic composites using the Composite-Based Additive Manufacturing (CBAM) process. Carbon/Nylon 12 and Carbon/PEEK composites were fabricated and evaluated through mechanical (compression, tensile, flexural, and impact) and thermal (DSC and TGA) tests. Carbon/PEEK exhibited superior mechanical performance, with 97.5% higher tensile strength, 79.8% higher elastic modulus, and 59.6% higher flexural strength compared to Carbon/Nylon 12. Thermal testing showed that Carbon/PEEK had higher thermal stability, beginning degradation at 350 °C versus 298 °C for Carbon/Nylon. These results indicate that CBAM-fabricated Carbon/PEEK composites are suitable for applications requiring high strength and temperature resistance.

Linking Molecular Structure Evolution To Mechanical Degradation During Environmental Aging In Conventional And Recyclable Epoxy Systems, Ben T. Jewell

Dissertations, Master's Theses and Master's Reports

The long-term performance of polymeric materials in extreme environments is governed by complex chemical and physical aging processes that alter their molecular structure and mechanical integrity. Conventional thermoset epoxies, while widely used in structural applications, are particularly susceptible to oxidative degradation at elevated temperatures, leading to embrittlement and loss of structural integrity. In the first part of this work, diffusion-limited oxidation (DLO) in a bulk structural epoxy was systematically investigated to establish the link between heterogeneous microstructural evolution and macroscopic mechanical degradation. High-temperature oxidation experiments were conducted in a controlled environmental chamber, and the resulting chemical, thermal, and mechanical changes …

Side-By-Side Evaluation Of The Outgassing Rate And Ultimate Pressure Achieved Inside Tubes Made Of Low-Carbon And Stainless Steel, Aiman H. Al-Allaq, Md Abdullah Mamun, Matt Poelker, Abdelmageed Elmustafa

Mechanical & Aerospace Engineering Faculty Publications

The hydrogen outgassing rate of a vacuum chamber made of AISI 1020 low-carbon steel was found to be notably smaller than a similar chamber made of AISI 316L stainless steel following heat treatment at 150 degrees C. When the chambers were baked at 400 degrees C, the outgassing rate of the 1020 low-carbon steel chamber was approximately 2000 times smaller than that of the 316L stainless-steel chamber. After quantifying hydrogen outgassing rates, vacuum chambers made of 1020 low-carbon steel and 316L stainless steel were heated for a prescribed duration and then pumped with an ion pump and nonevaporable getter pump …

Novel Design And Fabrication Of A High-Speed Transient Heat Flux Sensor For Application To Rotating Detonation Engines, Zachary Todd Tallman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rotating detonation engine (RDE) combustion systems have been a topic of interest in the pressure gain combustion community for their benefits over traditional gas turbine engine combustors. However, cooling requirements for these engines are significantly higher and less predictable than those of non-detonating engines. To understand and quantify the high-speed heat transfer dynamics within an RDE, a novel high-frequency heat flux sensor is presented. This study aims to design a robust, single-sided sensor that can withstand the high temperature and harsh environment of an RDE for extended durations. Screen printing is used to deposit a layered, platinum-yttria-stabilized zirconia (YSZ) film …

Potential Of Lidar And Hyperspectral Sensing For Overcoming Challenges In Current Maritime Ballast Tank Corrosion Inspection, Sergio Pallas Enguita, Jiajun Jiang, Chung-Hao Chen, Samuel Kovacic, Richard Lebel

Electrical & Computer Engineering Faculty Publications

Corrosion in maritime ballast tanks is a major driver of maintenance costs and operational risks for maritime assets. Inspections are hampered by complex geometries, hazardous conditions, and the limitations of conventional methods, particularly visual assessment, which struggles with subjectivity, accessibility, and early detection, especially under coatings. This paper critically examines these challenges and explores the potential of Light Detection and Ranging (LiDAR) and Hyperspectral Imaging (HSI) to form the basis of improved inspection approaches. We discuss LiDAR’s utility for accurate 3D mapping and providing a spatial framework and HSI’s potential for objective material identification and surface characterization based on spectral …

Gas-Generating Reactive Materials: Design, Evaluation And Effect Of Morphology On Their Ignition And Combustion, Purvam Mehulkumar Gandhi

Dissertations

This work investigates optimizing gas-generating reactive materials, focusing on particle morphology's effect on ignition and combustion behavior. Metal-based gas-generating energetic materials (EMs) are promising alternatives to replace traditional CHNO compounds. Design of advanced metal-based EMs requires consistent ways of evaluating how their characteristics affect their ignition and combustion. Many relevant evaluation approaches exist; however, the results may be difficult to compare directly across different studies. Commonly, experimentalists ignite metal-based EMs in enclosed chambers and report pressures, P. However, direct comparison of these pressures is hindered by variations in the chamber volume, V, and the EM mass, m. To standardize the …

Multiphysics Modeling And Experimental Validation Of High-Strength Steel In Laser Powder Bed Fusion Process, M. Rangapuram, S. Babalola, J. W. Newkirk, L. N. Bartlett, F. W. Liou, K. Chandrashekhara, Stephen R. Cluff

Materials Science and Engineering Faculty Research & Creative Works

Laser powder bed fusion (LPBF) is a subset of the additive manufacturing process in which a laser beam selectively joins the metal powder into a desired part in a sequential layer process. Owing to its complex nature of rapid heating and cooling of the melt pool, there is a need to understand the melt pool behavior and its effects on the final manufactured part. a densely packed powder bed is highly desirable for fabricating a superior part using the LPBF process. in this work, discrete element model was used to generate powder beds with realistic powder properties and various factors …

Kinetic Modeling Of Dust Grain Dynamics In Electrostatic Sieving, Aaron Berkhoff, Easton Ingram, Fateme Rezaei, Jeffrey Smith, David Bayless, William Schonberg, Daoru Han

Chemical and Biochemical Engineering Faculty Research & Creative Works

A new kinetic particle modeling framework was developed to investigate electrostatic transport of lunar regolith dust particles with applications to the concept of electrostatic sieving. the new approach is based on kinetic particle dynamics and includes major modules of sampling the particle size distribution, solving electric fields, and tracking motion of charged dust grains. a case study for a concept of electrostatic sieving was chosen to validate the new model. the simulation achieved similar performance of particle size classification as reported in the literature. the new model is computationally efficient (takes a few minutes on a PC-type laptop computer) so …

Experimental Study Of Drag Characteristics And Dust Removal Performance Of A Hybrid Wet-Filter Precipitator, Hang Yi, Zifeng Yang, Deqiang Chang, Xinjiao Tian, Jingxian Liu

Mechanical and Materials Engineering Faculty Publications

With their advantages of high dust removal efficiency and low drag characteristics, hybrid wet-filter precipitators have great potential for dust control in coal mines, but the underlying mechanisms are not well understood. In this study, to help fill this knowledge gap, a hybrid wet-filter precipitator consisting of a 40-layer metal filter and a defogger device is designed and a prototype is constructed. Experiments are conducted to investigate its drag characteristics under wind velocities from 0.85 to 5.68 m/s and its dust removal performance under wind velocities of 2 and 4 m/s. On the basis of results with the initial design, …

Development And Processing Of Shape Memory Polymer Composites (Smpcs) For Application In Structural Robotics And Robotic Sensors., Kavish Sudan

Electronic Theses and Dissertations

Shape Memory Polymers (SMPs) have attracted significant attention since their introduction in the 1980s due to their remarkable ability to regain their original shape from a temporarily deformed state when exposed to an external stimulus, typically heat. This shape memory effect, driven by thermal transitions such as the glass transition temperature (T_g) or melting temperature (T_m), has made SMPs highly attractive for applications in soft robotics, aerospace, and biomedical devices. However, SMPs face challenges such as limited mechanical strength, thermal stability, and electrical conductivity, which hinder their broader adoption in advanced applications. To address these challenges, …

Tension–Compression Fatigue Of A Hybrid Polymer-Matrix/Ceramic-Matrix Composite At Elevated Temperature, Marina B. Ruggles-Wrenn, Joshua Schmidt

Faculty Publications

Fully reversed tension–compression fatigue of a hybrid material comprising polymer matrix composite (PMC) co-cured with a ceramic matrix composite (CMC) was investigated. The PMC portion had a polyimide matrix reinforced with 15 plies of carbon fibers woven in an eight-harness satin weave (8HSW). The CMC portion had three plies of a quartz-fiber 8HSW fabric in a zirconia-based ceramic matrix. The hybrid PMC/CMC was developed for use in aerospace thermal protection systems (TPS). Hence, the experimental setup aimed to simulate the TPS service environment—the CMC side was kept at 329 °C, whereas the PMC side was open to laboratory air. Compression …

Modeling Powder Spreadability In Powder-Based Processes Using The Discrete Element Method, Austin T. Sutton, M. Hossein Sehhat, Ming C. Leu, Joseph W. Newkirk

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Powder-bed fusion (PBF) processes refer to a subset of Additive Manufacturing (AM) techniques where powder is spread on the build-plate before melting (by a laser or electron beam). While PBF processes are attractive due to their ability for realizing complex structures that are either difficult or impossible to create through conventional means, the parts fabricated with these techniques can exhibit defects such as pores, inclusions, and excessive surface roughness. To minimize these defects, much research has been dedicated towards process maturation by optimizing laser or electron beam parameters. However, these developmental efforts typically do not address the recoating process where …

Alternative Applications Of Composite Materials To Reduce Radar Cross Section, Mark Patterson

Mechanical & Aerospace Engineering Theses & Dissertations

The use of carbon nanoparticles and graphene in composite materials has created a foundational shift in enhancing performance across mechanical, thermal, and electrical properties. Such applications are vital in the aerospace industry. However, there has not been such a focus on the material use for reducing radar cross section (RCS). Historically, RCS is minimized by designing sharp geometric shapes to deflect or dissipate the incoming electromagnetic waves away from the receiving antenna. However, these designs are not always optimized for aerodynamics. The goal of this research is to understand the application of composite materials and specifically carbon nanotubes (CNTs) to …

Using Dft On Ultrasound Measurements To Determine Patient-Specific Blood Flow Boundary Conditions For Computational Hemodynamics Of Intracranial Aneurysms, Hang Yi, Zifeng Yang, Luke Bramlage, Bryan Ludwig

Mechanical and Materials Engineering Faculty Publications

Boundary conditions (BCs) is one pivotal factor influencing the accuracy of hemodynamic predictions on intracranial aneurysms (IAs) using computational fluid dynamics (CFD) modeling. Unfortunately, a standard procedure to secure accurate BCs for hemodynamic modeling does not exist. To bridge such a knowledge gap, two representative patient-specific IA models (Case-I and Case-II) were reconstructed and their blood flow velocity waveforms in the internal carotid artery (ICA) were measured by ultrasonic techniques and modeled by discrete Fourier transform (DFT). Then, numerical investigations were conducted to explore the appropriate number of samples (N) for DFT modeling to secure the accurate BC by comparing …

Interaction Of Particles With Plasma And Shock Produced By Pulsed Spark Discharge, Shomik Mukhopadhyay

Dissertations

Interactions of powders with high-temperature plasma and shockwaves occur in diverse scenarios, such as nuclear blasts, accidental industrial dust explosions, solid propellant combustion in explosive charges and when removing contaminants from surfaces. Electrostatic Discharge (ESD), known for generating shock and plasma, is a promising lab-scale technique for simulating these interactions. Studies with ESD involved placing powders near a spark-producing gap between electrodes and observing mechanical and chemical processes like particle motion and ignition. A limited range of spark conditions and material properties have been tested, which facilitated the development and validation of preliminary computational models describing this system. Significant gaps …

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 …

Starfish: A Compact, Biomimetic, And Adaptive Shape Memory Alloy Orbital Debris Remover, Katelyn Branaman

Doctoral Dissertations and Master's Theses

This thesis aims to turn the tides on the orbital debris issue through the fabrication and demonstration of a compact, biomimetic, and adaptive shape memory alloy actuated orbital debris remover. The design, referred to as Starfish, is discussed in detail along with its fabrication process and object capture ability. A hard skeleton crafted from PETG was combined with shape memory alloy wires and extension springs to create a biomimetic structure that operates similar to the human hand, capable of gripping a wide range of objects. Relevant simulations were performed and discussed, the iterative fabrication process used to create each component …