Space And Defense Vol. 16 No. 1 Summer 2025 Special Issue On Arctic Security (Whole Issue),
2025
University of Nebraska at Omaha
Space And Defense Vol. 16 No. 1 Summer 2025 Special Issue On Arctic Security (Whole Issue), Editors Space And Defense
Space and Defense
Articles that cover issues on Artic Security.
Note: PDF passed accessibility checker before upload.
Analyzing The Impact Of Passive Techniques On Aircraft Wing Hysteresis: An Experimental And Numerical Study,
2025
Grand Valley State University
Analyzing The Impact Of Passive Techniques On Aircraft Wing Hysteresis: An Experimental And Numerical Study, Brendan Worton
Masters Theses
This study investigates the effects of passive flow control techniques on aerodynamic hysteresis primarily in NACA 2412 (cambered) and 0012 (symmetric) wings. Computational Fluid Dynamics (CFD) was used to design and evaluate three passive techniques, including outward-facing dimples, leading-edge tubercles, and rectangular vortex generators, prior to experimental validation. These techniques demonstrated improvements in aerodynamic performance in CFD simulations and were therefore selected for wind tunnel testing to analyze their aerodynamic performance and influence on hysteresis behavior. A custom, cost-effective experimental setup was designed and developed to facilitate efficient angle-of-attack control and data acquisition. It incorporates a three-axis force sensor, stepper …
Development Of Turbulence Models For Prediction Of Hypersonic Flows Using Compressibility Corrections And Uncertainty Quantification With Emphasis On The Wray-Agarwal Model,
2025
Washington University – McKelvey School of Engineering
Development Of Turbulence Models For Prediction Of Hypersonic Flows Using Compressibility Corrections And Uncertainty Quantification With Emphasis On The Wray-Agarwal Model, Aidan Robert Murphy
McKelvey School of Engineering Graduate Student Theses & Dissertations
Accurate prediction of high-speed compressible turbulent flows remains one of the most significant challenges in Computational Fluid Dynamics (CFD), especially in the realm of hypersonic vehicle design. These flow regimes involve significant aerodynamic heating and shock-wave boundary layer interactions (SBLI) which remain a significant challenge for the current CFD prediction capabilities. While Direct Numerical Simulation (DNS) and Large-Eddy Simulation (LES) provide high-fidelity solutions, their computational demands limit their usability, making the Reynolds-Averaged Navier-Stokes (RANS) equations an efficient alternative for many industrial aerodynamic applications. Traditional RANS techniques, while computationally efficient, often provide limited accuracy in high-speed flows due to the presence …
Development, Numerical Simulation, And Optimization Of Quiet Supersonic Transport Aircraft And Extension Of The Wray-Agarwal Algebraic Transition Model To Include Compressibility And Crossflow Effects,
2025
Washington University – McKelvey School of Engineering
Development, Numerical Simulation, And Optimization Of Quiet Supersonic Transport Aircraft And Extension Of The Wray-Agarwal Algebraic Transition Model To Include Compressibility And Crossflow Effects, Dean Ryan-Simmons
McKelvey School of Engineering Graduate Student Theses & Dissertations
In the first part of this thesis, the goal of the research is to implement and extend multi fidelity methods for conceptual design and optimization of a commercial supersonic transport (SST). Most modern commercial aircraft operate at a cruise condition between Mach 0.7 and 0.9, as this is the optimal trade-off of flight efficiency, operational cost, and adherence of noise regulations for overland travel. Advancements in aviation propulsion fuel efficiency and design materials suggests a primary restraint on commercial supersonic transport is noise regulations. At speeds above Mach 1, the shock waves generated by the airframe are strong enough to …
Transition And Instability Characteristics Of The Separated Shear Layer Formed At Low Reynolds Number Over Three-Dimensional Irregular Rough Surface,
2025
SASTRA Deemed to be University
Transition And Instability Characteristics Of The Separated Shear Layer Formed At Low Reynolds Number Over Three-Dimensional Irregular Rough Surface, Ganesh Kt Mr
Theses and Dissertations
The present experimental work investigates the effects of irregularly roughened surfaces and imposed streamwise pressure gradients on the topological, transitional, and instability characteristics of the laminar separated shear layer (SSL). Experiments are conducted in the low-speed wind tunnel for 𝑅𝑒𝑡=30000, based on the thickness of the airfoil model, t, and freestream turbulence intensity, fst = 0.8%. The airfoil model used in this study features a semicircular leading edge followed by a constant-thickness flat portion and a pitchable trailing-edge flap. Test conditions include two rough surfaces: sandblasted (SB) and sand-deposited (SD), and flap deflections: 𝛽=−30° and 𝛽=+30°, imposing adverse (APG) and …
Bio-Inspired Electroactive Polymer (Eap) Sensors For Surface And Canal Flow Sensing In Dynamic Environments,
2025
University of Nevada, Las Vegas
Bio-Inspired Electroactive Polymer (Eap) Sensors For Surface And Canal Flow Sensing In Dynamic Environments, Nazanin Minaian
UNLV Theses, Dissertations, Professional Papers, and Capstones
Nature can often create some of the most efficient and elegant solutions to complex problems, and engineering stands to benefit greatly from these time-tested designs. One of the more sophisticated examples of this is the lateral line system in fish: a distributed network of superficial and canal neuromasts that enables aquatic species to detect fluid disturbances with remarkable precision. This dissertation leverages that biological framework to explore the potential of electroactive polymers (EAPs), aiming not just to replicate structure, but to emulate function.Two classes of EAPs form the basis of this work: electroactive plasticized polymer gels (EPPGs) and ionic polymer-metal …
Orbital Maneuvers And Interplanetary Trajectory Design Via Reinforcement Learning,
2025
Embry-Riddle Aeronautical University
Orbital Maneuvers And Interplanetary Trajectory Design Via Reinforcement Learning, Roberto Cuéllar Rangel
Doctoral Dissertations and Master's Theses
This dissertation investigates the application of reinforcement learning (RL) to the design and optimization of low-thrust spacecraft trajectories, with an emphasis on autonomy, adaptability, and robustness in the presence of system uncertainties and unmodeled perturbations. Classical approaches to low-thrust trajectory design are predominantly grounded in optimal control theory, which relies on the availability of precise dynamical models and often requires problem-specific reformulation and solver tuning. While optimal control methods offer high accuracy under deterministic conditions, their sensitivity to stochastic disturbances and computational limitations in highly nonlinear or uncertain environments pose significant challenges for future autonomous space missions.
To address these …
Life And Performance Improvement Trenches,
2025
AFIT/CI
Life And Performance Improvement Trenches, Thomas J. Praisner, John R. Farris, Connor Wiese
AFIT Patents
A blade outer air seal assembly includes a plurality of seal segments circumferentially disposed about an array of blades rotatable about an axis, each of the plurality of seal segments having a radially inner surface facing a tip of each blade of the array of blades, the radially inner surface having an arrangement of trenches formed therein, and a radially outer surface opposite the radially inner surface. The arrangement of trenches is disposed between 30% and 80% of a chord of a blade of the array of blades as taken at the respective tip, and the arrangement of trenches is …
Satellite Passive Ranging Metasurface Optics For Space Rendezvous And Proximity Operations,
2025
CFD Research
Satellite Passive Ranging Metasurface Optics For Space Rendezvous And Proximity Operations, Zachary Coppens, Cameron Vo, Addison Long, Jeremy Harris
Space Dynamics Laboratory Publications
SDL Presentation on Satellite Passive Ranging Metasurface Optics for Space Rendezvous and Proximity Operations
An Inexpensive, Open, And Extensible Hardware-In-The-Loop Cubesat Test And Simulation Infrastructure,
2025
Portland State University
An Inexpensive, Open, And Extensible Hardware-In-The-Loop Cubesat Test And Simulation Infrastructure, Andrew Greenberg, Glenn Lebrasseur, Max Eltzroth, Rose Edington, Anna Meneely, Maxwell Millar
Small Satellite Conference
We have developed an inexpensive, open source, and extensible hardware-in-the-loop (HIL) test and simulation system to allow even small CubeSat teams to dramatically improve their testing infrastructure to increase reliability during flight.
Design Of A Fan-Based Test Stand For Evaluating Multicopter Handling In Turbulent Flow,
2025
Embry-Riddle Aeronautical University
Design Of A Fan-Based Test Stand For Evaluating Multicopter Handling In Turbulent Flow, Salim Roig
Doctoral Dissertations and Master's Theses
With the innovation of eVTOL rotorcraft the need to analyze how turbulence-induced disturbances from orthogonal flow affect various rotorcraft configurations outside of simulations have grown significantly. To investigate the behavior of this type of flow and how it interacts with various rotorcraft configurations, a turbulent inducing test stand was designed and constructed. The test stand will have two walls of computer fans arranged in an L-shape frame, creating wind gusts that simulate the non-linear turbulent wind experienced by eVTOL. This also aids the Eagle Flight Research Center (EFRC) in their efforts to better understand how disturbances affect the handling qualities …
Calibration And Validation Of The Thermal Finite Element Model For Er120s-G Wire Arc Directed Energy Deposition Using Infrared Cameras And Thermocouples,
2025
Mississippi State University
Calibration And Validation Of The Thermal Finite Element Model For Er120s-G Wire Arc Directed Energy Deposition Using Infrared Cameras And Thermocouples, Joshua Mykl Bassett
Theses and Dissertations
Wire Arc Directed Energy Deposition (WA-DED) is a promising additive manufacturing method for producing large metallic components with high deposition rates and low costs. However, its rapid heat input can lead to residual stress, microstructural changes, and dimensional inaccuracies. Accurate thermal modeling is essential to mitigate these effects. This study presents a thermal calibration of a finite element model (FEM) for ER120S-G using thermocouples and infrared (IR) imaging. Thermal data were gathered from three experiments to complete the calibration of the FEM . Calibration focused on tuning the Goldak heat source parameters, power efficiency, and heat transfer coefficients to minimize …
Opto-Mechanical Properties Of Monocrystalline Germanium,
2025
Utah State University Space Dynamics Laboratory
Opto-Mechanical Properties Of Monocrystalline Germanium, Phil Scott, Lennon Reinhart, Patrick Strong, Ryan Luder, Shayler Backlund, Trent Newswander
Space Dynamics Laboratory Publications
SDL Presentation on Opto-Mechanical Properties of Monocrystalline Germanium
Impact Of Uncertainties On Structures Damage Tolerance Parameters,
2025
Embry-Riddle Aeronautical University
Impact Of Uncertainties On Structures Damage Tolerance Parameters, Breno De Bruns
Doctoral Dissertations and Master's Theses
This research aims to enhance the understanding and management of aerospace structural integrity. Traditional fracture control methods, such as damage tolerance analysis (DTA), assume deterministic factors, considering uncertainties inherent in material properties, inspections, and operational conditions only at the final stage by applying safety factors. This research seeks to incorporate these uncertainties throughout the analysis by integrating Monte Carlo simulation with Linear Elastic Fracture Mechanics (LEFM). The objective is to investigate how varying parameters affect crack growth prediction and the effectiveness of inspection strategies. The methodology involves systematically analyzing inspection intervals, considering factors like material properties, probability of detection (POD), …
Atmospheric Waves Experiment (Awe) Thermal Balance: Internal Characterization, Correlation, And Lessons Learned,
2025
Utah State University Space Dynamics Laboratory
Atmospheric Waves Experiment (Awe) Thermal Balance: Internal Characterization, Correlation, And Lessons Learned, Matt Ralphs, Mike Holt
Space Dynamics Laboratory Publications
The Atmospheric Waves Experiment (AWE) is providing the first global characterization of atmospheric waves that originate in Earth’s lower atmosphere and affect space weather. The instrument has been installed on the International Space Station’s (ISS) ExPRESS Logistics Carrier (ELC) site 1 since November 2023. The AWE flight thermal balance test at Space Dynamics Laboratory (SDL) was unique in that the radiation exchange from the radiators was not tested prior to flight. Instead, heaters were placed on the radiators to simulate environmental heat and control the boundary temperatures. Multi-layer insulation (MLI) was installed over the radiators and heat flow meters were …
High-Heat Transfer Lithium-Ion Batteries: A New Era In Battery Thermal Management,
2025
Applied Thermoelectric Solutions LLC
High-Heat Transfer Lithium-Ion Batteries: A New Era In Battery Thermal Management, Alfred J. Piggott, Jeffrey S. Allen, Ahmad A. Pesaran
Michigan Tech Publications
Despite advances in lithium-ion battery technology, critical challenges remain that must be addressed to accelerate electric vehicle (EV) adoption and global energy transformation. Significantly improved battery thermal management (BTM) is key to overcoming these challenges. BTM approaches focus on increasing heat transfer coefficients via air, liquid, or refrigerant cooling, but less attention is given to reducing the battery's thermal resistance, a major bottleneck for heat transfer. This work introduces a novel approach to reduce battery thermal resistance by integrating in-plane heat transfer with optimized cell geometry, minimized thermal resistances, and reduced interfacial resistances, representing a departure from previous methods. The …
Mae Enewsbrief Apr- June 2025,
2025
Michigan Technological University
Mae Enewsbrief Apr- June 2025, Department Of Mechanical And Aerospace Engineering, Michigan Technological University
Department of Mechanical and Aerospace Engineering eNewsBrief
No abstract provided.
Analysis On Plasma Propulsion Thruster Material Reconfiguration For Thrust Stabilization,
2025
Old Dominion University
Analysis On Plasma Propulsion Thruster Material Reconfiguration For Thrust Stabilization, Chinedumu Chidiebere Okafo
Mechanical & Aerospace Engineering Theses & Dissertations
Rocket propulsion has been a primary focus for scientific and technical advancement supporting space exploration. For long-duration, low-thrust space missions, propulsion systems designed with plasma energy as the primary source for generating thrust are of high interest. Plasma energy, like electric propulsion, involves the excited state of ionized atoms, where the ionized particles are separated and then act as a propellant to push a spacecraft in the intended direction for flight. Although more energy efficient compared to traditional rocket systems, plasma propulsion has the deficiency of consistent erosion of the metallic containment substrate, as plasma is being generated and released …
Mission-To-Designs: Automating Uav Conceptual Design Generation,
2025
Clemson University
Mission-To-Designs: Automating Uav Conceptual Design Generation, Nana A. Adjei
All Theses
The conceptual design stage of Unmanned Aerial Vehicles (UAVs) is an exploratory phase where designers are tasked with developing and evaluating a wide range of viable design concepts, considering different geometries and configurations based on mission requirements. The goal is to identify the most suitable design after the exploration for further development and progression to the next phase. Several tools and frameworks have been developed to assist designers in this stage, each offering unique capabilities, but all with the common aim of aiding in the efficient development and evaluation of conceptual designs. This is important in the UAV design process …
Robust Adaptive Rigid Body State And Mass Property Estimation Via Unscented Kalman Filter On Tse(3) With Process Noise Estimation,
2025
Embry-Riddle Aeronautical University
Robust Adaptive Rigid Body State And Mass Property Estimation Via Unscented Kalman Filter On Tse(3) With Process Noise Estimation, Herman Gunter
Doctoral Dissertations and Master's Theses
Mass property estimation, including mass, center of mass, and moment of inertia, is a crucial yet challenging problem in spacecraft autonomy and astrodynamics. Knowledge of mass properties of a spacecraft is essential for future astronautical missions, as changes in the mass properties of a spacecraft due to a shift in cargo distribution often require a careful and costly recalculation to ensure applied control inputs produce the desired results. As spacecraft missions grow in both duration and number, meeting the need for precise and accurate measurements becomes increasingly complex. Stochastic effects, such as angle and velocity random walks, along with persistent …
