Aerospace Engineering Commons^™

Adiabatic And Overall Effectiveness Superposition Theory For Upstream Phantom Cooling On A Film Cooled Leading Edge, Nathaniel J. Stout

Theses and Dissertations

Film cooling experimentation aims to improve the cooling performance while minimizing the amount of coolant flow redirected from the compressor. The coolant flow that is used for film cooling reduces the maximum thrust any gas turbine engine can produce. Finding creative ways to improve cooling performance without increasing the amount of coolant used, like phantom cooling, is essential for the gas turbine industry to improve engine performance while increasing turbine components’ lifespan. Phantom cooling refers to any secondary cooling effect that propagates downstream from its original cooling application to cool subsequent turbine components. Phantom cooling is actively gaining more attention …

Thin-Filament Pyrometry In A Rotating Detonation Engine, Theodore B. Guetig

Theses and Dissertations

Rotating Detonation Engine (RDE) proves beneficial by creating a pressure rise across the combustor rather than a pressure drop seen in traditional aircraft combustors. Coupled with this high pressure is a high temperature in the detonation engine that is difficult to measure as it varies spatially and temporally. Thin-Filament Pyrometry (TFP) was performed on a 6-in RDE to measure these high temperatures. Temperature profiles were obtained over a variety of mass flows, equivalence ratios, and different axial locations within the RDE providing insight into the mixing process and where the heat release occurs. Successful determination of these temperature profiles within …

Metaheuristic Techniques To Optimize Trajectory Planning Of Uav Swarms: Enhancing Data Acquisition In Wireless Sensor Networks, Nada Ali Mohamed Ahmed Ahmed

Theses and Dissertations

Unmanned aerial vehicles (UAVs) have become increasingly integrated into various applications due to their cost-efficiency, rapid deployment, flexible maneuvers, and enhanced performance. This has led to the development of a new field called UAV-assisted Wireless Sensor Networks (U-WSNs), which focus on data routing, network performance optimization, and planning UAV trajectories between sensor nodes in wireless sensor networks. In this thesis, a new framework has been proposed to manage a swarm of UAVs cooperatively serving large-scale wireless sensor networks. The framework consists of three optimization problems: distributing sensor nodes among UAVs, finding optimal trajectories in the presence of obstacles, and performing …

Investigation Of Coupled Fluid-Structure Interactions In Supersonic Flows, Seshendra Palakurthy

Theses and Dissertations

The skin panels used in high-speed flights are exposed to various types of loads, such as inertial, elastic, and aerodynamic loads. In addition, oblique shock impingement can cause flow separation and unsteady aerodynamic loading, which can reduce vehicle performance and result in acoustic noise and viscous heating. These loads, when combined, can result in a complex dynamic response, such as flutter. Flutter is characterized by sustained unsteadiness or structural vibrations. Although flutter might not be immediately harmful, it can lead to fatigue failure of the structural components. A vast amount of literature already exists on the panel flutter induced by …

Learning-Based Feature Identification For Rendezvous And Capture Of Non-Cooperative Space Objects, Trupti Mahendrakar

Theses and Dissertations

In recent years, On-Orbit Servicing (OOS) and Active Debris Removal (ADR) have attracted increasing interest due to growing concerns about space debris. This debris poses a significant risk to spacecraft, as collisions can catastrophically end missions and potentially trigger a cascading chain reaction of more debris. Space debris ranges from tiny paint chips to large non-functional spacecraft and even launch vehicle components. One way to mitigate the formation of additional space debris is to reduce the total number of large non-cooperative resident space objects present in operational orbits. This can be achieved through two approaches: de-orbiting these objects as part …

Improving Robustness Of Learning-Based Approaches In Autonomous Systems And Engineering Education, Godwyll Aikins

Theses and Dissertations

This dissertation advances the development of robust learning-based approaches across two complementary domains: engineering education and autonomous systems. Through four studies, this research addresses critical challenges in preparing data-proficient engineers and developing reliable autonomous systems that can operate under uncertainty and incomplete information. The engineering education study examines how mechanical and aerospace engineering undergraduates conceptualize and develop data proficiency skills essential for modern engineering practice. Through interviews with 27 students, the research employs the How People Learn framework to analyze student perspectives on information literacy, data interpretation, and computational thinking. The findings inform pedagogical strategies for developing data proficiency in …

Loss Of Control In General Aviation: An Investigation Into The Mooney M20 And The Full Trimming Tail Design, Trenton Neil Wright

Theses and Dissertations

Loss of Control (LOC) in General Aviation (GA) remains one of the leading causes of aviation accidents, with 94% of all accidents in 2022 occurring in this sector, and 42% attributed directly to LOC [2][3]. This thesis focuses on the Full Trimming Tail (FTT) in Mooney aircraft, hypothesizing that the FTT design significantly increases the likelihood of LOC, particularly during go-arounds and touch-and-go landings. Prior studies have shown that certain trim systems can amplify pitch-up moments following rapid configuration changes, leading to stalls or LOC if not adequately managed by the pilot [23][24][25].

This research utilized a combination of logistic …

Thermo-Structural Analysis Of Stiffened Fgm Panels With Cutout Under Non Uniform And Localized In-Plane Edge Loadings, Balaraman P

Theses and Dissertations

Most aerospace applications involve structural components with a high stiffness-toweight ratio and excellent resistance to high temperatures. Buckling, vibration as well as other forms of instability are the consequences of a non uniform stress field caused by non uniform, localized edge loadings and the presence of discontinuities. In order to improve structural properties and increase load bearing capacity, designers concentrate on structural integrity, especially in high-temperature applications. The adaptability and customizable nature of functionally graded material (FGM) make it valuable in addressing these challenges.

Metal-ceramic FGM is an advanced composite material that integrates the distinctive qualities of metal and ceramic …

Guidance, Navigation, And Control For Multi-Agent Inspection Of An Unknown Space Object, Mark R. Mercier

Theses and Dissertations

On-orbit inspection is a rapidly growing mission that enables extending the life of aging legacy space systems through refueling, replacing, or upgrading components. For an inspection operation, multiple agents taking observations simultaneously can more quickly map an RSO and assure an inspection is complete regardless of RSO dynamics. A multi-agent guidance, navigation, and control (GNC) scheme must be designed with cooperation in mind to achieve inspection objectives, while leveraging the unique capabilities of a distributed inspection system. This work splits the GNC system into two parts composed of an offline guidance scheme for translational reference trajectory generation and an online …

Heuristic Design Of Cislunar Space Situational Awareness Architectures, Jacob A. Dahlke

Theses and Dissertations

The growing interest in the cislunar domain, which encompasses geosynchronous Earth orbit (GEO), the Moon, and the region where Earth-Moon gravitational effects are the primary influence, necessitates the development of tools to ensure safe and successful exploration. Space situational awareness (SSA) involves monitoring an environment to detect, track, identify, and catalog space objects. While most SSA experience comes from near-Earth operations, expanding into the cislunar domain presents significant challenges due to its vast expanse—greater than 10 times the radius of GEO—and the unique dynamics governed by the Circular Restricted Three-Body Problem (CR3BP) influenced by both Earth and Moon gravitational forces. …

Optimal Placement Of Artificial Hair-Cell Airflow Sensors For Bioinspired Flight-By-Feel, Alex C. Hollenbeck

Theses and Dissertations

The Sparse Sensor Placement Optimization for Prediction (SSPOP) algorithm reduces highdimensional airflow data to a low-dimensional sparse approximation to identify an optimal placement for any number of sensors on airfoil or wing models of arbitrary shape and size, and outperforms conventional optimization techniques in accuracy and speed. For 2D flow this algorithm found a sensor placement solution (design point, or DP) which predicts AoA to within 0.10 degrees and ranks within the top 1 percent of the design space. On 3D wing models SSPOP found four-sensor DPs ranked well within the top 0.10 percent. Experimental validation with velocity and pressure …

End-To-End Full-Width Induction Welding Of Unidirectional Tape-Based Thermoplastic Composites, Jaspreet Singh Pandher

Theses and Dissertations

The current large scale application of thermoset composite materials in large, twin aisle, civil transport aircraft have resulted in significant performance enhancements, such as aerodynamic efficiency, weight reduction, and durability. These large aircraft are, however, produced in relatively low numbers. For the next generation smaller single aisle aircraft, large scale applications of composites are of interest in the airframe. Application of composites in single aisle aircraft will require not only proof of similar and/or significant performance improvements, but also proof of adequate manufacturing rates. One option to achieve both is large scale application of thermoplastic instead of thermoset composites.

Thermoplastic …

Towards The Induction Welding Of Complex, Curved Thermoplastic Composite Structures, Andrew Cole Cromer

Theses and Dissertations

Recent advancements in the aerospace industry, coupled with the anticipated future significance of air travel, have spurred research aimed at increasing manufacturing production and aircraft flying efficiency by implementing new materials and assembly methods. Advanced air mobility (AAM), a subset of the aerospace industry, is anticipated to become a crucial component of the transportation infrastructure in densely populated regions. To meet the expected demand, there is a need for investigations into novel manufacturing and joining methods. This industry necessitates materials that are lightweight, durable, and amenable to high-rate production. One potential avenue under exploration is the utilization of thermoplastic composites. …

High-Rate Production Of Thermoplastic Composite Structures For Urban Air Mobility Vehicles Utilizing Fastener-Free Assembly Methods, Robert H. Shumpert

Theses and Dissertations

This study aimed to develop a manufacturing plan for a Thermoplastic fiber-reinforced propeller blade for urban air mobility applications. This propeller blade offer a few unique challenges including the complex geometries of the blade. Another important aspect of the blade is using fusion bonding methods to increase the strength of joints in the product while reducing weight from fasteners and adhesives. This manufacturing process will be validated by producing a physical demonstrator to ascertain the efficacy of the manufacturing techniques used. First, the techniques that will make up the manufacturing plan must be selected. To do this, a review of …

The Study And Development Of Autonomous Scarf Repair For Composite Structures: A Focus On Advanced Air Mobility Vehicles, Stephen Hilton

Theses and Dissertations

“I’m sorry I haven’t been able to truly give you a solution to thermoplastic repair” – Arnt. Director GKN Global Tech Center, 2023

The aerospace industry has a prevalence of composite materials due to their outstanding benefits to the mechanical properties of structures while serving to reduce the overall structure weight. With the development of the Advanced Air Mobility market, there is an anticipated growth in the number of composite structures. Also, with the manufacturing environment of the 21st century, these composite structures are more and more being made using thermoplastic composites that can be recycled at the end of …

Study On Pilot Response Time To Reject Takeoff With One Engine Inoperative (Oei), Lydia Savitri Scrivens

Theses and Dissertations

The FAA regulation 14 CFR § 25.109 defines accelerate-stop testing for transport-category multiengine aircraft. It specifies that testing must include 2-second distance equivalent at engine failure speed VEF to simulate time taken for pilot to reject takeoff. However, pilot response time is widely debated. The purpose of this study is to determine pilot response time in rejecting a takeoff due to the failure of one engine during the takeoff roll.

Seven multiengine rated pilots participated in this study, which was conducted in a Baron 58 in the X-Plane 12 flight simulator. During the recruiting process, test subject candidates provided their …

Engine Performance Of An Electric Airplane With Partial Battery Capability, Hannah Yasmine Scrivens

Theses and Dissertations

As electric aircraft are developed and certified, knowledge of electric aircraft performance during complete or partial battery failures can be useful to determine an aircraft’s limitations and capabilities of completing an emergency landing, especially during takeoff and low-altitude climbs, as well as fully characterizing the potential aircraft performance. The results of this research will be useful in developing regulations and procedures pertaining to energy reserves and emergencies. This paper presents the results of a Pipistrel electric airplane climb power ground test that was conducted by the author and Florida Tech faculty. In the test, one of the airplane’s batteries was …

Disposal And Earth-Moon Escape From Cislunar Orbits Using Non-Linear Programming Techniques, Sam T. Loeffler

Theses and Dissertations

This thesis involves theoretical and numerical analysis of trajectories off of cislunar orbits to determine the reachability and escape of various impulsive Δ^→v. The research will propagate trajectories using three body dynamics from various orbit families around the Earth-Moon Lagrange points and find low energy transfers that escape the Earth-Moon system. In order to achieve this, various different nonlinear programming solvers in MATLAB will be used to explore low energy impulsive escape transfers from common cislunar orbit families given long periods of computation time. After many points on cislunar orbits are analyzed, the data will be analyzed to …

Developing A Lean Spacecraft Test And Evaluation Architecture For A Contested Space Domain, Stephen K. Tullino

Theses and Dissertations

The US Space Force (USSF) is currently investigating possible opportunities to improve the testing paradigm of spacecraft in order to get assets on-orbit faster, while maintaining suitable quality to meet mission needs in a contested space environment. To support this goal, USSF’s approach to test and evaluation (T&E) is centered around the concept of integrated test. In this research, the space text lexicon is defined, addressing the ambiguities on exactly what integrated test is with respect to spacecraft systems development and on-orbit mission assurance. This research considered any statistical trends in categorical discrepancies (i.e., anomalies) during prelaunch integration and test …

Experimental Investigation On Downstream Characteristics Of S809 Airfoil With And Without Passive Flow Control Device, Mano S

Theses and Dissertations

The wake behaviour of extended flat plate (EFP) and serration in the trailing edge of S809 airfoil is presented in this experimental study using wind tunnel testing for several freestream turbulence intensities (TI). The clustering wind turbines in wind parks has recently been an important problem, as it involves determining the number of wind turbines to be installed to increase the power output.

The downstream wake characteristics are one of the most significantparameter that influence the performance of subsequent wind turbines.These wind turbine blades are made up of airfoil cross sections and need to be studied in detail. A series …

Analysis Of The Temperature Dynamics In General Aviation Brake System, Rajnea Anthony Coley

Theses and Dissertations

As aircraft brakes are subjected to intense heat generation during landings and braking maneuvers, comprehending the temperature dynamics is essential for ensuring optimal performance, longevity, and, most importantly, the safety of flight operations. This paper dives into understanding heating and cooling in the brake systems of the Piper Aircraft PA28. In order to investigate the thermal behavior of aircraft brake components, this study evaluates a variety of general aviation braking scenarios, from light to heavy braking, including stop-and-go landings, full-stop taxi backs, and continuous braking while taxiing. It was noticeable that light braking exhibits slight temperature increases and cooling rates. …

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 …

Caelus: Cubesat Array For The Exploration Of The Uranus System, Dylan George Heidenrich Barnes

Theses and Dissertations

Following recommendations from the 2023-2032 Planetary Science and Astrobiology Decadal Survey, we propose a novel Pre-Phase A level Uranus exploration mission concept that is centered on using swarms of small spacecraft to observe the Uranus system. This mission could act as a supplement to the Flagship Uranus Orbiter and Probe mission detailed in said Decadal Survey. We propose launching a 4,500 kg spacecraft on an Earth-Jupiter-Uranus gravity assist transfer trajectory with a transfer time of six years, launching in 2033 and arriving at Uranus in 2039. This shorter transfer time and accelerated development timeline would allow for an earlier arrival …

High-Fidelity 3d Reconstruction Of Space Bodies Using Machine Learning And Neural Radiance Fields, Timothy Jacob Huber

Theses and Dissertations

In the era of burgeoning space exploration, the growing population of spacecraft heightens the inevitability of collisions. While traditional imagery remains effective for damage assessment, its lack of 3D representation of the object necessitates more advanced approaches. This research delves into cutting-edge methodologies, with a primary focus on leveraging machine learning and computer vision technologies to enhance the precision and efficiency of damage assessment by taking imagery of a space body and creating a 3D model. The study extensively investigates TransMVSNet, a neural network code employing classical computer vision techniques such as multi-vision stereo (MVS) and depth maps. This approach …

Experimental And Numerical Analysis Of Laminar And Transitional Flow Through Annular Corrugated Pipes, Joseph Russell Sargent

Theses and Dissertations

This dissertation presents studies on pressure loss through annular corrugated pipes to determine a friction factor coefficient using nitrogen. Ten different corrugated pipes’ geometries were evaluated via testing and experimentation. The ratio of corrugation height to inner diameter varied from 0.233 to 0.333 and the ratio of corrugation pitch to inner diameter varied from 0.181 to 0.446. Nitrogen flow rates between 0.25 to 94.4 standard liters per minute were used, resulting in Reynolds numbers, based on the corrugated pipe inner diameter, from 100 to 23,000. The experimental set-up was validated using smooth-pipe pressure loss measurements and the derived friction factor …

System Identification For Motion Control Of Unmanned Aerial Vehicles Platform, Raj Ramesh Agarwal

Theses and Dissertations

Comprehensive research on Unmanned Aerial Vehicles (UAV) system identification for motion control parameters is presented in this thesis, with a focus on the necessity of precise control and improved performance. Using Pseudorandom Binary Sequence (PRBS) and Normally Distributed Random Numbers, it presents a unique technique for excitation of UAV dynamic systems. It also shows how effective random signals are in time-domain identification for precise control in a range of flying circumstances. The piece of research includes a thorough analysis and implementation of various approaches and its further improvements, highlighting the benefits and drawbacks of each. These approaches include the free …

Deep Learning System Identification, Linearization And Control Of Dynamical Systems Utilizing Koopman Theory With Applications In Orbital Systems, George Mario Nehma

Theses and Dissertations

The computational and complexity burden of current linearization techniques is one that is a hinderance in the application of real world guidance, navigation and control systems. With the advancements in Deep Neural Networks, large data handling and Koopman Theory, the possibility of global linearizations of nonlinear systems is more prominent. This work demonstrates the capability of a Deep Neural Network learned Koopman operator to transform a nonlinear system into a Linear Time-Invariant system. The method presented is applied to both two purely dynamical systems and one controlled system to emphasize the ability for the technique to be applied in all …

Investigation Of The Effect Of Internal Reynolds Number And Advective Capacity Ratio On Gas Turbine Film Cooling Parameters, John P. Di Lella

Theses and Dissertations

The desire for more powerful engines drives higher turbine inlet temperatures and a greater need to cool them. Experimentalists attempt to match cooling effectiveness between two conditions by matching several non-dimensional parameters, one of which is the coolant warming factor. The first investigation of this study examines the effect of the internal Reynolds number and the advective capacity ratio on the coolant warming factor by making use of a computational model and four different gases. It indicates the non-negligible and opposing effects of external convection and solid conduction on the coolant warming factor at matched internal Reynolds number and advective …

Trajectory Optimization Via Direct Collocation Methods Of Boost-Glide Vehicle With Newtonian Aerodynamic Model, Andrew Bonavita

Theses and Dissertations

In this work, a Newtonian aerodynamic model was developed for an elliptic cone glide geometry at a variety of angles of attack, and a functional relationship between an input angle of attack and the vehicle lift and drag coefficients was developed. This model was used in a direct orthogonal collocation framework to simulate a series of boost-glide trajectories, with objectives of minimum distance to target, minimum time to target, and maximum velocity to target. The optimal control problem was then expanded into a reachability study, considering a wide range of additional scenarios, along with studies on the vehicle range capabilities. …

Influence Of Environmental Barrier Coatings On The Overall Effectiveness Of A Film Cooled Ceramic Matrix Composite Plate, Shane P. Lindsay

Theses and Dissertations

Silicon carbide ceramic matrix composites, a promising new potential upgrade over the conventional metals currently used for jet engine turbine blades, have a propensity to oxidize in a combustion environment. Engine manufacturers often apply environmental barrier coatings to prevent the composites from oxidizing. What is unclear, however, is how environmental barrier coatings effect underlying composite temperatures. This research examined the coatings’ effects by first characterizing the influence of environmental barrier coatings on the underlying temperature of a protected ceramic, then evaluating the significance of lateral conduction for cooling a coated ceramic, and finally comparing cooling results for coated and uncoated …