Aerospace Engineering Commons^™

Influence Of The Sst K-Ω Stress-Limiter Coefficient On Transonic Shock Buffet Prediction For The Oat15a Supercritical Airfoil, Melinawo Vowotor

College of Graduate Studies: Theses & Dissertations

Transonic shock buffet predictions using the Shear Stress Transport (SST) k–ω turbulence model are known to be sensitive to the stress-limiter coefficient a₁, yet no systematic investigation of this sensitivity exists. This thesis presents a parametric study of a₁ for two-dimensional URANS simulation of shock buffet on the OAT15A supercritical airfoil at M = 0.73 and Re = 3 × 10⁶. Eleven a₁ values (0.25–0.37) are examined at α = 3.5°, and a matrix of five a₁ values across five angles of attack (3.0°–3.9°) maps the interaction with incidence. The results reveal that a₁ acts as a bifurcation parameter: a …

Fused Filament Fabrication Additive Manufacturing Of 17-4 Ph Stainless Steel: Process–Structure–Property Relationships In Magnetic Materials, Maanav Patel

Theses and Dissertations

Additive manufacturing (AM) enables the fabrication of complex metallic components through layer-by-layer processing directly from digital models. Among AM techniques, material extrusion–based processes such as fused filament fabrication (FFF) provide an accessible method for producing metal parts using filament feedstocks composed of metal powders and polymer binders. When applied to precipitation-hardening stainless steels such as 17-4 PH, the processing route and heat treatments can influence the resulting microstructure and functional properties. This work investigates the magnetic behavior of 17-4 PH stainless steel fabricated using FFF and evaluates how heat treatment conditions influence measured magnetic properties. Samples were produced and analyzed …

Assessment And Comparison Of Selected Carbon Ablation Models In Hypersonic Free-Flight And Arc-Jet Conditions, Andrew Steven Heider

Masters Theses

Accurate prediction of ablative thermal protection system (TPS) performance is critical for hypersonic vehicle design. However, numerical prediction of ablation remains challenging because results are influenced by complex physics and the choice of surface chemistry model and assumptions made in material response calculations. The objective of this work is to evaluate several carbon ablation models and their implementation within modern computational fluid dynamics (CFD) codes. Numerical simulations were performed using NASA’s LAURA flow solver and the commercial CFD code ANSYS Fluent, which coupled Navier-Stokes with surface chemistry models describing carbon oxidation, nitridation, and sublimation reactions. Several reaction sets were considered, …

Autonomous Navigation Development And On-Ground Validation For Satellite Rendezvous And Proximity Operations, Logan Banker

Masters Theses

Spacecraft rendezvous and docking are critical mission phases for various applications of spaceflight, including active debris removal (ADR) and in-orbit servicing, assembly, and manufacturing (ISAM). While previous missions utilized humans to perform rendezvous and docking, this style of mission greatly increases safety risks and cannot be implemented on a large scale. Autonomous servicing satellites provide a path towards scalable rendezvous and proximity operations (RPO) because these autonomous agents do not require human intervention. This work presents a lightweight convolutional neural network (CNN) for the navigation system of an agent which analyzes monocular images and predicts the target's position and orientation …

Modeling Hepa Filter Media Performance And Evaluation Of Filtration Leak Test Success, Daniel M. Abraham, Steven J. Eckels, Shahin N. Amiri

Civil & Environmental Engineering Faculty Publications

This research presents a cost-effective microscale modeling analysis of high-efficiency particulate air (HEPA) filter media. We analyzed leak-free and leaking media with known leak sizes. A three-dimensional fibrous model with non-homogeneous fiber diameters (0.2–2 µm) and a packing density of 7.5% was developed to replicate a HEPA filter sheet (H14) microstructure. The objective was to simulate and analyze the pressure drop and collection efficiency of nanofibrous media for aerosol particles with a diameter of d_p ≤ 0.5 µm. The results were compared to prior experimental and theoretical models, exhibiting a high level of agreement with pressure drop and efficiency …

Experimental And Numerical Study On The Stability Limits Of Ammonia And Ammonia/Hydrogen Flames Inside A Toroidal Jet-Stirred Reactor, Guillermo Alberto Barrios Cadenas

Graduate Studies Theses and Dissertations 2026

Ammonia’s (NH₃) properties as a carbon-free hydrogen carrier, its phase characteristics, and its wide global infrastructure present a solid case as a potential surrogate for carbon-based aviation fuels. Delivering a zero-emission NH₃-based engine requires careful integration and optimization of the combustor and thermal management systems, a process that requires high-fidelity chemical reacting models experimentally validated through the use of simplified combustors. This study investigates NH₃ fundamental combustion characteristics at conditions relevant to aviation gas turbines using a newly constructed toroidal jet-stirred reactor (TJSR) facility. Lean blow-off (LBO) experiments were carried out for NH₃ blends …

Temperature And Speciation Measurements Of Aluminum-Laden Detonation Flows Via A Three-Color Wavelength Modulation Spectroscopic Sensor, Marc B. Etienne

Graduate Studies Theses and Dissertations 2026

Tunable diode lasers are widely used and are known to be great options for continuous wave lasing applications. Because of their stability and spectral selectivity, they have become an important diagnostic tool for modern combustion research. Previous combustion research, particularly those focused on solid and hybrid rocket systems, have shown that the interaction of aluminum with a reacting flow can greatly affect the dynamics and the thermochemical properties of the surrounding gas, therefore understanding the effects of aluminum-laden flows is critical for the advancement of these propulsion systems. However, due to the high degree of optical interference, high temperatures, and …

Structural Batteries For Aerospace Applications, Tariqullah Wardak

Honors Undergraduate Theses

There is increasing pressure on the aviation sector to lower carbon emissions and switch to entirely electric and hybrid propulsion systems. However, the feasibility of standard lithium-ion batteries for long-range aircraft is limited, as they add substantial weight and occupy significant volume. Structural batteries, which combine load-bearing capability with energy storage, offer a potential pathway to lighter and more efficient aerospace systems.

This work investigates a carbon-fiber-based structural battery that utilizes carbon fiber as both a current-collecting, load-bearing electrode and a component of the composite structure. In contrast to lithium-ion chemistries, a zinc-based aqueous electrolyte is chosen for better environmental …

Anisotropic Second-Harmonic Ince-Gaussian Beam Generation Using Nbobr2 Holograms, Jayanta Deka, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Ince-Gaussian (IG) modes are a complete and orthogonal set of solutions to the paraxial wave equation in elliptic coordinates representing a continuous transition between Hermite-Gaussian modes and Laguerre-Gaussian modes. Chip-scale platforms to generate IG beams have great significance for various applications, including optical trapping and micromanipulation of particles, optical communication, and quantum optics. On the other hand, materials with high optical anisotropy are crucial for building polarization-sensitive optical devices. In this context, niobium oxide dihalides are a new class of ferroelectric materials exhibiting strong, tailorable, and highly anisotropic second-harmonic generation responses. Here, we report the generation of highly anisotropic second-harmonic …

Dynamic Modeling Of The Earth's Trapped Proton Environment, Xiaojing Xu, Steve R. Blattnig, Francis F. Badavi, Martha S. Clowdsley, Edward J. Semones

Physics Faculty Publications

Context: Reliable prediction of space radiation exposure is critical for safeguarding spacecraft systems and ensuring astronaut health during missions. Accurate radiation risk assessment for space mission requires advanced models of the Earth’s trapped proton environment. These models must reflect temporal variations driven by geomagnetic field evolution and solar cycle modulation. Existing static models, such as AP8 and IRENE-AP9, are not designed to fully capture these evolving conditions. Aims: This paper presents a dynamic modeling method for the prediction of trapped proton fluxes, which incorporate time-dependent variations due to geomagnetic field evolution and solar cycle fluctuations. Methods: The …

Students For The Exploration And Development Of Space (Seds) Air Brake Subsystem: High-Altitude Autonomous Apogee Modulator System For High-Powered Rockets (Haamshr), Camden J. Maclean, Matthew Wharton, Nick Revis, Colin Guido

Honors Theses and Capstones

The objective of this project was to research, design, fabricate, and analyze an autonomous apogee modulation air brake system for the University of New Hampshire (UNH) Students for Exploration and Development of Space (SEDS) high-powered rocket as competitors in the Friends of Amateur Rocketry – Oxidizers Uninhibited Tournament (FAR-OUT) competition.

This air brake system would be developed with considerations for full autonomy, structural reliability, and repeatable deployment. The design would also be easily integrated into the existing high-powered rocket airframe and mechanically simple to increase reliability and practical functionality. The final design would be evaluated using finite element analysis simulation …

Gaze Transition Entropy And Automation Trust In Multitasking Workspace, Yusuke Yamani, Austin Jackson, Tetsuya Sato, Feyishola Ashimi, Michael S. Politowicz, Eric T. Chancey, Makoto Itoh

Psychology Faculty Publications

Safe flight operation requires visual scanning across multiple displays in a cockpit, which collectively represent the state of the aircraft and supporting automation. Trust is a crucial factor that drives human-automation interaction, and recent work has suggested a relationship between an operator's visual attention and automation trust. One index that captures predictability of eye movements between different areas of interest is gaze transition entropy. The current work reanalyzed data from Sato et al., which examined eye movement patterns and trust in automation associated with the system monitoring task of the Multi-Attribute Task Battery. Results showed credible positive correlations between the …

Performance Evaluation Of Thick Carbon Fiber-Reinforced Laminates Manufactured Using Six-Magnetron Microwave System, Nayan Pundhir, Sourav Bolar, Kumbla Chandrashekhara, Kristen Donnell, Jim Lua, Kalyan Shrestha, Rui Li

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Microwave curing is a fast, energy-efficient, and a viable alternative to conventional thermal curing processes. It has been widely adopted for processing carbon fiber-reinforced polymer composites because the high electrical conductivity of carbon fibers enables strong microwave coupling. In this study, IM7/Cycom 5320-1 unidirectional prepreg has been used to fabricate 64-layer laminated composites. Symmetric cross-ply ([0°/90°]16S) and a quasi-isotropic ([45°/90°/−45°/0°]8S) layup have been investigated. A custom-built six-magnetron microwave applicator and an autoclave were employed to manufacture the composite panels. Degree of cure of the manufactured laminates was evaluated via differential scanning calorimetry. Interfacial bonding and porosity of the microwave-cured laminates …

Multiphysics Simulation And Experimental Validation Of Phase Transformation And Hardness In Jominy End-Quenched Low-Alloy Steels, J. S. Alabi, E. Heidari, M. F. Buchely, K. Chandrashekhara, S. N. Lekakh, R. J. O'Malley, V. A. Athavale, A. Kumar

Materials Science and Engineering Faculty Research & Creative Works

High-volume industrial continuous hot-rolled steel heat treatment processes involve sophisticated multi-phase modeling. The performance of a given process can be optimized by coupling phase transformation kinetics with the cooling conditions of the process. This study develops a multiphysics model to simulate an intensive quenching process for steel, which is inherently transient and highly dependent on numerous parameters. The simulated object was a Jominy end-quenched specimen geometry using two commercial steels, AISI 4130 and AISI 4140, with the goal of transferring a verified methodology to the heat treatment process for industrial heavy-section products (bars, slabs). The simulation employs thermal, mechanical, and …

Simulated Lunar Gravity Testing Of A Magnetic And Electrostatic System For Beneficiating Lunar Regolith, Blake A. Coffman, Gabriel Porter, Lindsay Manteufel, Mitchell Cottrell, Jeffrey D. Smith, David J. Bayless, William Shonberg, Frank D. Han, Fateme Rezaei, Kirby Runyon

Materials Science and Engineering Faculty Research & Creative Works

We present the design and testing of a lunar regolith beneficiation device that utilizes magnetic and electrostatic separation methods to concentrate desired minerals by removing unwanted material, such as the mineral anorthite, from bulk lunar regolith. The beneficiated materials would have value for downstream in-situ resource utilization (ISRU) processes such as metal extraction, oxygen extraction, and metal oxide additive manufacturing processes. The apparatus uses a dual-strength magnet system with N52 and N42 neodymium magnets to separate particles by magnetic susceptibility. The electrostatic separation system, which acts like a sieve, sorts the regolith simulant by particle size using a single-phase 50% …

Exploring Drone Technology For The Survey And Documentation Of Aerospace Archaeology Sites, David G. Morgan, Thomas R. Allen

Political Science & Geography Faculty Publications

This research examines the implementation of Unmanned Aerial Systems (UAS) during a pilot mission in Nike Park to support its aerospace preservation. Located in Carrollton, Virginia, it was a Cold War missile installation that formed part of the area’s air-defense network. This project aims to use a drone to capture high-resolution video and imagery of Nike Park’s Administrative Office Supply and PX building and the Nike Ajax missile to create virtual 3D models for the Isle of Wight County Museum’s exhibit. For this mission, the DJI Mini 4 Pro drone manually flew a circular flight pattern around the missile and …

Effects Of Hydrogen Enrichment And Premixing On Flame Stability In A High-Pressure Axial-Stage Combustor, Alexandre Fernandes C. Santiago Filho

Honors Undergraduate Theses

The addition of hydrogen to conventional fuels enhances reactivity and can increase the risk of flashback in premixed gas turbine combustors. This study investigates the effects of premixing length and hydrogen concentration on flame stability in a high-pressure axial-stage combustor. Experiments were conducted at the UCF Propulsion and Energy Research Laboratory using a two-stage configuration, where the primary stage provided a high-temperature vitiated crossflow using a hydrogen-piloted, premixed methane–air mixture, and hydrogen-enriched methane–air mixtures were injected through a concentric fuel-tube injector in the axial stage. Premixing length was varied for pure hydrogen flames, and hydrogen concentration was varied at a …

Assessment Of Simulation Software Used For Cubesat Gnc Verification And Validation By University Research Teams, Alexander Taiyo Newett

Masters Theses

As the growth in university satellite teams continues, along with the greater trend in the small satellite market, the need for a guidance, navigation, and control verification and validation pipeline suitable for these young and inexperienced teams becomes evident. Much of the mathematical theory and software implementation of GNC concepts are large hurdles for teams largely composed of undergraduate students.

Many software packages exist that can help these teams achieve GNC verification and validation. If the learning curves of these software packages can be overcome, new satellite teams have the opportunity to better build and test GNC algorithms that are …

Increasing Actuation Authority And Bandwidth For Aeromechanics Testing: A Piezoelectric-Based Approach, Sydney A. Giannuzzi

Graduate Studies Theses and Dissertations 2026

Flutter in turbomachinery poses significant risks to aerospace systems, requiring accurate identification of flutter boundaries to ensure operational safety. Traditional binary “flutter / no flutter” testing methods provide limited data without error margins. Aeromechanical Identification Methodology (AIM) offers a safer alternative by mapping aeromechanical damping across operational conditions using non-contact excitation. However, current AIM actuators are constrained to excitation frequencies below 500 Hz, limiting their effectiveness and applicability. To bridge this gap, this research analyzed and validated performance of a novel piezoelectric-based oscillatory flow injection valve (NOVA) designed to deliver high-bandwidth, high-authority actuation for expanded flutter boundary mapping.

NOVA was …

Evaluating The Impact Of Cognitive Distraction On Spaceflight-Relevant Task Performance Using Surface Electromyography And Motion Capture, Allyson K. Mitchell

UNF Graduate Theses and Dissertations

Cognitive distraction poses a risk to astronaut performance during complex, multitasking operations in spaceflight environments. This study examined the effects of cognitive load on neuromuscular coordination and task execution using surface electromyography (sEMG) and motion capture. Thirteen participants performed spaceflight-relevant tasks under undistracted and distracted conditions, with distraction induced through verbal questioning. EMG signals from eight upper-extremity muscles were processed using envelope filtering, peak normalization, and time normalization to enable inter-subject comparison, and group-level mean activation with standard deviation was analyzed. While overall muscle activation was similar between conditions, phase-dependent differences were observed, with undistracted trials showing higher activation during …