Engineering Commons^™

Experimental Measurements Of Hypseronic Instabilities Over Ogive-Cylinders At Mach 6, Jonathan Luke Hill

Theses and Dissertations

Hypersonic boundary layer transition experiments were performed in the Air Force Research Lab (AFRL) Mach 6 Ludwieg tube over a meter long ogive-cylinder model with interchangeable nose tip angles and bluntnesses. Measurements of instabilities were captured via focused laser differential interferometry (FLDI), surface mounted pressure sensors, and high speed Schlieren imagery at nominal unit Reynolds numbers ranging from 4.0*10⁶/m to 1.4*10⁷/m. This study attempts to isolate the effects of increasing tip angle and spherical bluntness on instabilities measured downstream over the cylindrical body of the model.

Laser Shock Peening Pressure Impulse Determination Via Empirical Data-Matching With Optimization Software, Colin C. Engebretsen

Theses and Dissertations

Laser shock peening (LSP) is a form of work hardening by means of laser induced pressure impulse. LSP imparts compressive residual stresses which can improve fatigue life of metallic alloys for structural use. The finite element modeling (FEM) of LSP is typically done by applying an assumed pressure impulse, as useful experimental measurement of this pressure impulse has not been adequately accomplished. This shortfall in the field is a current limitation to the accuracy of FE modeling, and was addressed in the current work. A novel method was tested to determine the pressure impulse shape in time and space by …

Spacecraft Position Estimation And Attitude Determination Using Terrestrial Illumination Matching, Liberty M. Shockley

Theses and Dissertations

An algorithm to conduct spacecraft position estimation and attitude determination via terrestrial illumination matching (TIM) is presented consisting of a novel method that uses terrestrial lights as a surrogate for star fields. Although star sensors represent a highly accurate means of attitude determination with considerable spaceflight heritage, with Global Positioning System (GPS) providing position, TIM provides a potentially viable alternative in the event of star sensor or GPS malfunction or performance degradation. The research defines a catalog of terrestrial light constellations, which are then implemented within the TIM algorithm for position acquisition of a generic spacecraft bus. With the algorithm …

Design And Analysis Of A Disk-Oriented Engine Combustor, Bennett M. Staton

Theses and Dissertations

In a novel approach to gas-turbine power production, an engine was designed and analyzed to use both a single-stage centrifugal compressor and single-stage radial in- ow turbine configured back-to-back. This air path reduced the axial length of the engine up to 60%, providing additional modularity in a gas-turbine engine that could be used to improve mobility of ground-based power units or increase the survivability of aircraft through the use of distributive propulsion. This increased modularity was made possible by the use of a circumferential ow combustor that substantially decreased the axial length of the burner and negated the need to …

A System Architecture For Phased Development Of Remote Suas Operation, Eric Ashley

Master's Theses

Current airspace regulations require the remote pilot-in-command of an unmanned aircraft systems (UAS) to maintain visual line of sight with the vehicle for situational awareness. The future of UAS will not have these constraints as technology improves and regulations are changed. An operational model for the future of UAS is proposed where a remote operator will monitor remote vehicles with the capability to intervene if needed. One challenge facing this future operational concept is the ability for a flight data system to effectively communicate flight status to the remote operator. A system architecture has been developed to facilitate the implementation …

Comparison Of Signaling Profiles In The Low Dose Range Following Low And High Let Radiation, Deepa M. Sridharan, Lung-Chang Chien, Francis A. Cucinotta, Janice M. Pluth

Environmental & Global Health Faculty Research

During space travel astronauts will be exposed to a very low, mixed field of radiation containing different high LET particles of varying energies, over an extended period. Thus, defining how human cells respond to these complex low dose exposures is important in ascertaining risk. In the current study, we have chosen to investigate how low doses of three different ion's at various energies uniquely change the kinetics of three different phospho-proteins. A normal hTERT immortalized fibroblast cell line, 82–6, was exposed to a range of lower doses (0.05–0.5 Gy) of radiation of different qualities and energies (Si 1000 MeV/u, Si …

Angular Correlation Using Rogers-Szego-Chaos, Christine Schmid, Kyle J. Demars

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Polynomial chaos expresses a probability density function (pdf) as a linear combination of basis polynomials. If the density and basis polynomials are over the same field, any set of basis polynomials can describe the pdf; however, the most logical choice of polynomials is the family that is orthogonal with respect to the pdf. This problem is well-studied over the field of real numbers and has been shown to be valid for the complex unit circle in one dimension. The current framework for circular polynomial chaos is extended to multiple angular dimensions with the inclusion of correlation terms. Uncertainty propagation of …

Dislocation-Oxide Interaction In Y2o3 Embedded Fe: A Molecular Dynamics Simulation Study, M. Mustafa Azeem, Qingyu Wang, Zhongyu Li, Yue Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Oxide dispersed strengthened (ODS) steel is an important candidate for Gen-IV reactors. Oxide embedded in Fe can help to trap irradiation defects and enhances the strength of steel. It was observed in this study that the size of oxide has a profound impact on the depinning mechanism. For smaller sizes, the oxide acts as a void; thus, letting the dislocation bypass without any shear. On the other hand, oxides larger than 2 nm generate new dislocation segments around themselves. The depinning is similar to that of Orowan mechanism and the strengthening effect is likely to be greater for larger oxides. …

Ground And In-Flight Calibration Of The Osiris-Rex Camera Suite, D. R. Golish, C. Drouet D'Aubigny, B. Rizk, D. N. Dellagiustina, P. H. Smith, K. Becker, N. Shultz, T. Stone, M. K. Barker, E. Mazarico, E. Tatsumi, R. W. Gaskell, L. Harrison, C. Merrill, C. Fellows, B. Williams, S. O'Dougherty, Michael Whitely, Jed Hancock, B. E. Clark, C. W. Hergenrother, D. S. Lauretta

Space Dynamics Laboratory Publications

The OSIRIS-REx Camera Suite (OCAMS) onboard the OSIRIS-REx spacecraft is used to study the shape and surface of the mission’s target, asteroid (101955) Bennu, in support of the selection of a sampling site. We present calibration methods and results for the three OCAMS cameras—MapCam, PolyCam, and SamCam—using data from pre-flight and in-flight calibration campaigns. Pre-flight calibrations established a baseline for a variety of camera properties, including bias and dark behavior, flat fields, stray light, and radiometric calibration. In-flight activities updated these calibrations where possible, allowing us to confidently measure Bennu’s surface. Accurate calibration is critical not only for establishing a …

Differential Vector Phase Locked Loop Gps Reception Method, James Brewer, John F. Raquet

AFIT Patents

A method for enhancing GPS location accuracy includes providing a base station receiver having a known surveyed location, and a roving receiver at a location distinct from the base station receiver. The method further includes receiving single-frequency code and carrier-phase measurements from the base station, and translating the single-frequency code and carrier-phase measurements to a Kalman filter-predicted location of the roving receiver. The translated single frequency code and carrier phase measurements are used to generate a local replica of the Kalman filter-predicted location signals for each channel of the roving receiver. The method further includes correlating the local replicas with …

Congressional Committee Resources On Space Policy During The 115th Congress (2017-2018): Providing Context And Insight Into U.S. Government Space Policy, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Article 1 of the US Constitution assigns the US Congress numerous responsibilities. These include creating new laws, revising existing laws, funding government programs, and conducting oversight of these programs' performance. Oversight of US Government agency space policy programs is executed by various congressional space policy committees, including the House and Senate Science Committees, Armed Services, and Appropriations Committees. These committees conduct many public hearings on space policy which invite witnesses to testify on US space policy programs and feature debate on the strengths and weaknesses of these programs. Documentation produced by these committees is widely available to the public, except …

Characterization Of Inertial Particles In The Turbulent Wake Of A Porous Disk, Kristin Nichole Travis

Dissertations and Theses

This study presents the findings of a wind tunnel experiment investigating the behaviour of micrometric inertial particles in the turbulent wake of a stationary porous disk. Various concentrations [Φ_v ∈ (2.95 x 10^-6 - 1.22 x 10^-5)] of polydisperse water droplets (diameter 13-41 µm) are compared to sub-inertial tracer particles. Hot-wire anemometry, phase Doppler interferometry and particle image velocimetry were implemented in the near and far wake regions to study the complex dynamics of the particles. Turbulence statistics and particle size distributions are presented and used to explore the particle wake interaction.

Near-Field Pressure Signature Splicing For Low-Fidelity Design Space Exploration Of Supersonic Aircraft, Christian R. Bolander, Douglas F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

As interest in supersonic overland flight intensifies, new ways to meet government restrictions on sonic boom loudness must be implemented. Low-fidelity aerodynamic tools, such as PANAIR, can estimate the near-field pressure signature that ultimately determines the loudness of the sonic boom at the ground. These tools can greatly benefit the exploration of large design spaces due to their computational efficiency. One of the limitations of low-fidelity tools is the accuracy of the solution produced, which is dependent on the fundamental physical assumptions made in the development of the governing equations. If flow patterns are produced that severely violate these fundamental …

Close Formation Flight Missions Using Vision-Based Position Detection System, Ashok Sarath Chandra Reddy Irigireddy

Doctoral Dissertations and Master's Theses

In this thesis, a formation flight architecture is described along with the implementation and evaluation of a state-of-the-art vision-based algorithm for solving the problem of estimating and tracking a leader vehicle within a close-formation configuration. A vision-based algorithm that uses Darknet architecture and a formation flight control law to track and follow a leader with desired clearance in forward, lateral directions are developed and implemented. The architecture is run on a flight computer that handles the process in real-time while integrating navigation sensors and a stereo camera. Numerical simulations along with indoor and outdoor actual flight tests demonstrate the capabilities …

Carbon Fiber Composite Recycling, Wolfe Dennis

All Undergraduate Projects

During construction of Boeing’s aircrafts, carbon fiber reinforced composites are used as the primary material for the wings of the aircraft. Excess material during the manufacturing process is trimmed and discarded as waste. Although there is no viable process thus far, these trimmings have the potential to be recycled and reclaimed to be used in various other manufactured products. The trimmings of carbon fiber composite are approximately 10-12 layers of material bonded together. This project focuses on delaminating the trimmings into individual layers so that the carbon can be pyrolyzed from the bonding resin. In order to separate the layers …

Test Article, Test Author

Documentation

Description

Tangle-Free Exploration With A Tethered Mobile Robot, Danylo Shapovalov, Guilherme Pereira

Faculty & Staff Scholarship

Exploration and remote sensing with mobile robots is a well known field of research, but current solutions cannot be directly applied for tethered robots. In some applications, tethers may be very important to provide power or allow communication with the robot. This paper presents an exploration algorithm that guarantees complete exploration of arbitrary environments within the length constraint of the tether, while keeping the tether tangle-free at all times. While we also propose a generalized algorithm that can be used with several exploration strategies, our implementation uses a modified frontier-based exploration approach, where the robot chooses its next goal in …

Mechanical And Aerospace Engineering, 2019-2020, College Of Engineering And Applied Sciences

Mechanical and Aerospace Engineering News

• Letter from the Chair
• The MAE Staff
• Dr. Zachary Asher
• Alumni Excellence Academy Inductees
• From Sunway University to Success in America
• Student Experience at the Oshkosh Airventure
• Parker-Hannifin Donates New Hydraulic Trainers
• Electric Ducted Fan Lab for the Aircraft Propulsion Course
• MAE Faculty

Drone Payload Storage & Release System (Dpsrs), Joseph E. Key

All Undergraduate Projects

The retail giant Amazon has become a household name synonymous with nearly instantaneous online shopping. What previously took weeks to deliver at exorbitant shipping fees can now arrive at your doorstep within two days—and all for free. This huge buyer incentive has skyrocketed the demand for online shopping, making Amazon the most valuable brand in the world. To meet this demand, Amazon and its distributors have proposed using drones to make deliveries. However, due to issues with cost and complexity, this has not yet materialized. As such, this project’s objective was to create a cheap and lightweight package-delivery system that …

Composite Ruddervator Replacement, Kelson Mills

All Undergraduate Projects

The Beechcraft V-tail Bonanza is a popular general aviation aircraft. Over 10,000 were built, but with the weakness of magnesium skinned control surfaces. Control surfaces on aircraft must be light, and precisely balanced. The V-tail Bonanza uses a unique “ruddervator” system, which combines the rudder and elevator into one surface to reduce drag, controlling the pitch and yaw of the aircraft. Magnesium was chosen by the designers for its lightweight properties, but corrodes badly and is becoming difficult to source for replacement parts. Aerodynamic flutter, from flexibility in the lightly built surface, and corrosion can cause breakup in flight, and …

A Generalized Low Order Model For Vortex Shedding From A Tandem Cylinder Arrangement Using Delay Coupled Van Der Pol Oscillators, Michael Soroka

Honors Undergraduate Theses

A generalized low order model (LOM) for the fluctuating lift coefficient caused by vortex shedding from a tandem cylinder pair is proposed to expand upon models from previous authors. This model could provide a reduced computational time method for collecting qualitative and quantitive data from a tandem shedding pair. A delay coupled system with sufficient bifurcation characteristics is developed to account for the different flow regimes (extended-body, reattachment, and co-shedding) which occur as cylinder spacing is varied. Coefficient and parameter fitting is performed to fit experimental data. Finally, results and physical interpretations of the interactions in the model are discussed. …

High Order Explicit Semi-Lagrangian Method For The Solution Of Lagrangian Transport And Stochastic Differential Equations, Hareshram Natarajan

CGU Theses & Dissertations

A semi-Lagrangian method is developed for the solution of Lagrangian transport equations and stochastic differential equations that is consistent with Discontinuous Spectral Element Method (DSEM) approximations of Eulerian conservation laws. The method extends the favorable properties of DSEM that include its high-order accuracy, its local and boundary fitted properties and its high performance on parallel platforms for the concurrent semi-Lagrangian and Eulerian solution of a class of time-dependent problems that can be described by coupled Eulerian-Lagrangian formulations. Such formulations include the probabilistic models used for the simulation of chemically reacting turbulent flows or particle-laden flows. Motivated by the high-fidelity simulation …

The Impact Of Human Assurance On Satellite Operations, Holly Handley, Dan Heimerdinger, Unal Tatar (Ed.), Adrian V. Gheorghe (Ed.), Omer F. Keskin (Ed.), Jean Muylaert (Ed.)

Engineering Management & Systems Engineering Faculty Publications

Mission assurance is a method to guarantee mission success against a known set of risks; mission assurance is generally represented as a probability against a threshold of acceptable performance. Human assurance can be considered as the likelihood of acceptable operator performance given a set of conditions that include the operator, the system, and the environment. Standard mission assurance models tend to assume a qualified crew, but do not include other aspects of the internal or external environment that may impact the reliability of the human operator. A human assurance model can be created that allows the exploration of the variability …

Design Of Banner Tow Mechanism For Bush Plane, Kyle Ciarrone, Ivan Martin, Rishabh Gadi, Tyler Brandt

Williams Honors College, Honors Research Projects

The 2019-2020 AIAA DBF objective was to design, build, and test a banner-towing bush plane that carries wooden passengers and luggage. Senior members on the team undertook the creation of the banner tow mechanism subsystem as their senior design project on behalf of the design team due to the challenge of its mechanical design and the aerodynamic considerations regarding its placement and enclosure aboard the aircraft. The competition as well as access to campus resources were canceled due to COVID-19, so full testing and integration of the mechanism was not achieved. However, the engineering design process was experienced from the …

Inertial Orbit Estimation Using Multiple Space Based Observers: A New Measurement Model, James Hippelheuser

Electronic Theses and Dissertations, 2020-2023

Presented within this work is a new method for inertial orbit estimation of an object, either known or unknown, adaptable to a network of low-cost observation satellites. The observation satellites would only require a monocular camera for line of sight measurements. Using the line of sight measurements of each observer, a pair of orthogonal geometric planes that intersect both the observation satellite and the target are created. The intersection of the two planes in the inertial frame defines the new measurement model that is implemented with multiple observation nodes. Total system observability is analyzed and the instantaneous (per node) observability …

Piezospectroscopic Sensing Systems - Multi-Scale And In-Situ Sensing Technology For Structural Integrity, Remelisa Esteves

Electronic Theses and Dissertations, 2020-2023

The aerospace industry relies on nondestructive evaluation (NDE) to ensure aircraft safety and will benefit from methods that allow for early damage detection. Photoluminescence piezospectroscopy (PS) has demonstrated stress and damage sensing of substrates when coupled with alpha-alumina nanoparticles in a polymer matrix applied as a sensor coating. Alpha phase alumina exhibits photoluminescent spectral emission lines (R-lines) that shift due to changes in the stress state of the alumina. The coatings' capability for sensing early subsurface damage suggests the potential for implementing stress sensing paint for integrity monitoring of aircraft structures. To achieve a viable stress sensing coating that can …

Dynamic Modeling And Simulation Of A Power Plant Steam Condenser On The Siemens Sppa-T3000 Platform, Mohammad Odeh

Electronic Theses and Dissertations, 2020-2023

With rapidly increasing computational power, modeling and simulation of complex systems is gradually becoming the norm for evaluating and predicting performance. This research focuses on modeling and simulating thermodynamic behavior of condensers within Combined Cycle Power Plants. This is particularly useful for power generation companies as this allows a wide range of operating conditions to be simulated and characterized without risking damage or the need to shut down the power plant, all of which results in losing revenue in the process. Moreover, being able to observe the thermodynamic evolution of the system provides useful insight into efficiency and response to …

Strategies For Improving The Success Rates Of Lean Six Sigma Projects, Victoria Reed

Walden Dissertations and Doctoral Studies

Ineffective Lean Six Sigma (LSS) project strategies can lead to excessive Lean Six Sigma (LSS) project costs. Manufacturing business leaders who fail to mitigate LSS project costs expose the LSS project to failure. Grounded in the theory of constraints, the purpose of this qualitative single case study was to explore successful strategies LSS project leaders use to mitigate project costs in manufacturing. The participants comprised 16 aerospace manufacturing business leaders located in the southeast and northwest regions of the United States, who successfully implemented strategies to mitigate LSS project costs. Data were collected from semistructured interviews, a focus group, and …

Investigating The Numerical Stability Of Using An Impedance Boundary Condition To Model Broadband Noise Scattering With Acoustic Liners, Michelle E. Rodio, Fang Q. Hu, Douglas M. Nark

Mathematics & Statistics Faculty Publications

Reducing aircraft noise is a major objective in the field of computational aeroacoustics. When designing next generation quiet aircraft, it is important to be able to accurately and efficiently predict the acoustic scattering by an aircraft body from a given noise source. Acoustic liners are an effective tool for achieving aircraft noise reduction and are characterized by a frequency-dependent impedance value. Converted into the time-domain using Fourier transforms, an impedance boundary condition can be used to simulate the acoustic wave scattering by geometric bodies treated with acoustic liners. A Broadband Impedance Model will be discussed in which the liner impedance …

Study Of Non-Ideal Effects On Shock Wave Propagation, Cory Kinney

Electronic Theses and Dissertations, 2020-2023

Shock tube experiments provide insightful data on combustion, emissions, and ablation characterization for a wide variety of defense and energy sector research topics. Accurate characterization of shock tube facilities is essential to verifying the accuracy of research data. Non-ideal effects, such as boundary layer growth, introduce uncertainty into pressure and temperature conditions, the primary independent variables of interest for shock tube research results. The effect of boundary layer growth on shock tube experiments was investigated by conducting simulations for University of Central Florida's two geometrically different shock tube using StanShock, a quasi-one-dimensional, reacting, compressible flow solver. The characteristic quantities considered …