Aerospace Engineering Commons^™

Insights Into The Magnetic Dead Layer In La0.7sr0.3mno3 Thin Films From Temperature, Magnetic Field And Thickness Dependence Of Their Magnetization, N. Mottaghi, M.S. Seehra, R. Trappen, S. Kumari, Chih-Yeh Huang, S. Yousefi, G.B. Cabrera, A.H. Romero, M.B. Holcomb

Faculty & Staff Scholarship

Experimental investigations of the magnetic dead layer in 7.6 nm thick film of La0.7Sr0.3MnO3 (LSMO) are reported. The dc magnetization (M) measurements for a sample cooled to T = 5 K in applied field H = 0 reveal the presence of negative remanent magnetization (NRM) in the M vs. H (magnetic field) measurements as well as in the M vs. T measurements in H = 50 Oe and 100 Oe. The M vs. T data in ZFC (zero-field-cooled) and FC (field-cooled) protocols are used to determine the blocking temperature TB in different H. Isothermal hysteresis loops at differ- ent T …

Parametric Investigation Of Combustion And Heat Transfer Characteristics Of Oscillating Linear Engine Alternator, Mehar Bade, Nigel N. Clark, Matthew C. Robinson, Parviz Famouri

Faculty & Staff Scholarship

An Oscillating Linear Engine Alternator (OLEA) has the potential to overcome the thermal, mechanical, and combustion inadequacies encountered by the conventional slider-crank engines. The linear engines convert the reciprocating piston motion into electricity, thereby eliminating needless crankshaft linkages and rotational motion. As the dead center positions are not explicitly identified unlike crankshaft engines, the linear engine exhibits different stroke and compression ratio every cycle and should manage the unfavorable events like misfire, rapid load changes, and overfueling without the energy storage of a flywheel. Further, the apparatus control and management strategy is difficult for OLEA when compared to conventional engines …

Study Of Material Compatibility For A Thermal Energy Storage System With Phase Change Material, Songgang Qiu, Laura Solomon, Ming Fang

Faculty & Staff Scholarship

The suitability of stainless steel 316L and Inconel 625 for use in a latent heat thermal energy storage (TES) system was investigated. A NaCl–NaF eutectic mixture with a melting temperature of 680 ◦C was used as the phase change material (PCM). Containers were filled with the PCM prior to heating to 750 ◦C, then examined after 100 and 2500 h of high-temperature exposure by analyzing the material surface and cross-section areas. A small amount of corrosion was present in both samples after 100 h. Neither sample suffered significant damage after 2500 h. The undesirable inter-granular grain boundary attack found in …

Air Data Sensor Fault Detection With An Augmented Floating Limiter, Fabio Balzano, Mario Luca Fravolini, Marcello R. Napolitano, Stephane D'Urso, Michele Crispoltoni, Giuseppe Del Core

Faculty & Staff Scholarship

Although very uncommon, the sequential failures of all aircraft Pitot tubes, with the consequent loss of signals for all the dynamic parameters from the Air Data System, have been found to be the cause of a number of catastrophic accidents in aviation history. This paper proposes a robust data-driven method to detect faulty measurements of aircraft airspeed, angle of attack, and angle of sideslip. This approach first consists in the appropriate selection of suitable sets of model regressors to be used as inputs of neural network-based estimators to be used online for failure detection. The setup of the proposed fault …

Learning Local, Quenched Disorder In Plasticity And Other Crackling Noise Phenomena, Stefanos Papanikolaou

Faculty & Staff Scholarship

When far from equilibrium, many-body systems display behavior that strongly depends on the initial conditions. A characteristic such example is the phenomenon of plasticity of crystalline and amorphous materials that strongly depends on the material history. In plasticity modeling, the history is captured by a quenched, local and disordered flow stress distribution. While it is this disorder that causes avalanches that are commonly observed during nanoscale plastic deformation, the functional form and scaling properties have remained elusive. In this paper, a generic formalism is developed for deriving local disorder distributions from field- response (e.g., stress/strain) timeseries in models of crackling …

Mechanical And Aerospace Engineering, 2017-2018, College Of Engineering And Applied Sciences

Mechanical and Aerospace Engineering News

• Letter from the Chair
• Introducing Dr. Jinseok Kim
• Use of 3D Printing at WMU Helps Borgess Cardiologist Plug Holes in the Heart
• Department of Mechanical and Aerospace Engineering Develops Semi-Virtual Reality Powered Wheelchair Simulator
• The Western Aerospace Launch Initiative (WALI)
• 2017 NSF I-Corps Experience of MAE team
• Matthew Baird's Internship Experiences at JPL and GRC
• More Department News
• Faculty Sabbaticals

Structured Light-Field Focusing 3d Density Measurements Of A Supersonic Cone, Ryonosuke Ozawa

Electronic Theses and Dissertations

This study describes three-dimensional (3D) quantitative visualization of density field in a supersonic flow around a cone spike. A measurement of the density gradient is conducted within a supersonic wind tunnel facility at the Propulsion and Energy Research Laboratory at the University of Central Florida utilizing Structured Light-Field Focusing Schlieren (SLLF). In conventional schlieren and Shadowgraph techniques, it is widely known that a complicated optical system is needed and yet visualizable area depends on an effective diameter of lenses and mirrors. Unlike these techniques, SLLF is yet one of the same family as schlieren photography, it is capable of non-intrusive …

The Effect Of Martensite-Fractions Assumptions In Shape Memory Alloy Springs, Christian Vazquez

Electronic Theses and Dissertations

This research addresses various models of a spring-mass system that uses a spring made of a shape memory alloy (SMA). The system model describes the martensite fractions, which are values that describe an SMA's crystalline phases, via differential equations. The model admits and this thesis contrasts two commonly used but distinct assumptions: a homogeneous case where the martensite fractions are constant throughout the spring's cross section, and a bilinear case where the evolution of the martensite fractions only occurs beyond some critical radius. While previous literature has developed a model of the system dynamics under the homogeneous assumption using the …

Aerodynamic Design And Analysis Of A Large-Scale Stall-Regulated H-Type Vertical Axis Wind Turbine For An Offshire Floating Installation, Brian Peter Hand

PhDs

Wind energy has witnessed a consistent expansion over the past decade, especially with the move to offshore installation. There is an increasing need to further exploit superior offshore wind resources, which is pushing multi-megawatt wind turbines into deeper water locations where the current popular horizontal axis wind turbine configuration is not entirely suitable. In particular, there has been a renewed interest in the vertical axis wind turbine (VAWT) configuration due to its inherent design attributes for an offshore floating application and also its potential to provide a significant reduction in the system cost of energy. However, challenges still remain as …

Non-Intrusive Optical Measurement Of Electron Temperature In Near Field Plume Of Hall Thruster, Peter J. Urban

ETD Archive

Currently there is a large interest in the use of more efficient means of propulsion in long term missions due to the costs and difficulties associated with placing and maintaining the needed fuel for conventional chemical systems in orbit. Mass reduction of upper stages will return large returns due to the great reduction in required lower stage fuel. Due to these factors, alternatives are undergoing active research, though this paper is concerned with the area of electrical propulsion. Electric propulsion is broadly defined as propulsion where the energization of the exhaust occurs via application of electromagnetic fields as opposed to …

Performance Trades For Multiantenna Gnss Multisensor Attitude Determination Systems, Nathan A. Tehrani, Jason N. Gross

Faculty & Staff Scholarship

We present various performance trades for multiantenna global navigation satellite system (GNSS) multisensor attitude estimation systems. In particular, attitude estimation performance sensitivity to various error sources and system configurations is assessed. This study is motivated by the need for system designers, scientists, and engineers of airborne astronomical and remote sensing platforms to better determine which system configuration is most suitable for their specific application. In order to assess performance trade-offs, the attitude estimation performance of various approaches is tested using a simulation that is based on a stratospheric balloon platform. For GNSS errors, attention is focused on multipath, receiver measurement …

Flow Control Of Tandem Cylinders Using Plasma Actuators, Jonah Larsen

Honors Undergraduate Theses

The flow over a set of tandem cylinders at a moderate Reynolds numbers (Re), and with different separation lengths has been studied. Two dimensional (2D) and three-dimensional (3D) plasma actuators were used to control the flow over the leading cylinder to change the vortex shedding, and subsequently the flow on the second cylinder. The 3D plasma actuator was segmented along the length of the cylinder with a spacing of λ = 4 while the 2D actuator simply ran straight down the span of the cylinder. Particle image velocimetry (PIV) measurements were used to investigate the flow along the central plane …

Specific Air Range (Sar) And How To Estimate It, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Affordable Small System Calibration & Tvac Testing, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Ensure that your sensor will perform correctly during operation by validating image quality, radiometric performance, and operation temperature performance!

The Space Dynamics Laboratory (SDL) has been calibrating electro-optical sensors for over 50 years. During this time, SDL has designed and developed a collection of specialized equipment that is available for calibrating smaller optical systems, which can be very affordable.

Optimal Maneuvers For Safe Rpo Using Relative Orbital Elements And Sequential Convex Programming, Nicholas G. Ortolano, David K. Geller, Aaron Avery

Space Dynamics Laboratory Publications

Passive safety of flight constraints for orbital rendezvous and proximity operations trajectory design are imposed as a means for ensuring zero probability of collision in the event of a passive failure on the chaser satellite. For a chaser satellite near a target satellite in a near circular reference orbit, relative orbital elements are used to develop safety of flight constraints. Using relative orbital elements, the problem is formulated as a minimum ∆v convex optimization problem in which the optimal transfer trajectories are guaranteed to not pass within a prescribed distance of the target satellite in the event of a …

Thermal Straps: High-Performance Thermal Management, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Thermal straps efficiently transfer heat from a heat source to a temperature sink while minimizing the transfer of mechanical loads. SDL has been pioneering solderless flexible thermal straps (a.k.a. thermal links) since 1994.

Monolith: Spacecraft, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

SDL’s Pearl spacecraft architecture delivers the performance, reliability, and mission flexibility needed for demanding small satellite missions. The Pearl architecture draws from common sets of components to build 3U, 6U, 12U, and custom sizes with variations in mission capability, parts quality, and radiation tolerance. This flexibility enables our professional staff to develop systems specific to each mission while drawing on a common design to maintain reliability and costs.

Snpp Cris Noise Characterization And Relative Response After 5 Years In Space, Kori Moore, Mark Esplin, Deron Scott

Space Dynamics Laboratory Publications

CrIS Background

Satellite-based, infrared, Fourier transform spectrometer

• Provides Earth surface, atmospheric, and weather observations
• Global coverage twice daily

Launched and operational CrIS instruments

• Suomi National Polar-orbiting Partnership (SNPP) spacecraft, launched Oct. 2011, operational since Apr. 2012
• SNPP follow-on system (J1) launched Nov. 2017, expected operational spring 2018

A Performance Analysis Of On-Board Numerical Propagators, Simon Shuster, David Geller, Tyson Smith

Space Dynamics Laboratory Publications

On-board targeting, guidance, and navigation relies on orbit propagation algorithms that must strike a balance between accuracy and computational efficiency. To better understand this balance, the performance of numerical propagation methods is analyzed for LEO, GEO, and Molniya orbits. A numerical propagator consists of a set of differential equations describing perturbed orbital motion whose solution is approximated using a numerical integration method. This paper compares Cowell, Encke-time, Encke-beta, and Equinoctial Elements formulations over a range of integration function evaluations for a given set of perturbations and integrators. Function evaluations are shown to be a reasonable approximation of normalized computation time. …

Slanted-Edge Mtf Focus Test Verification With Prf Testing To Establish Best Focus Position Of Infinite Conjugate Space Optical Systems, Lennon Reinhart, Trent Newswander, Duane Miles, David W. Riesland, Deron Scott

Space Dynamics Laboratory Publications

For earth-viewing, fixed-focus, space optical systems, carefully finding the best focus position of the instrument is critical to achieving the best possible image performance and mission success. For such space optical systems, modulation transfer function (MTF) test data is directly applicable to system optical resolution. Furthermore, MTF test products can be combined to predict overall imaging performance. The infinite conjugate slanted-edge MTF test can be used in ground testing to identify best focus of the optical system while taking into account the entire imaging system, operational parameters, and simulated operational environment. The point-response function (PRF) test can be used to …

Characterization Of Acoustic Modes In Aeroengines, Michelle Otero

Electronic Theses and Dissertations

Acoustic instabilities remain a key design concern faced in the development of liquid rocket engines. The interaction between the acoustic modes and the occurring combustion reactions can be detrimental to the engine. The fluctuating pressure waves resulting from the flame oscillations in the system can potentially lead to engine failure. For this reason, research in acoustic instabilities and methods to minimize the influences on the engine, has maintain interest in the aerospace community. The scope of this study was to design, optimize and characterize acoustic behaviors of a scaled rocket combustion chamber simulating acoustic pressure waves. Tangential and longitudinal acoustic …

Neowise: Near Earth Object Wide-Field Infrared Survey Explorer, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

NEOWISE began as the Wide-field Survey Explorer (WISE), a highly sensitive astronomical telescope that surveyed the entire sky in four mid‐infrared bands spanning from 2.6 to 26 microns. Launched in December 2009, WISE scanned the entire sky one and a half times and cataloged hundreds of millions of astronomical objects, including many asteroids, brown dwarf stars, and ultra‐ luminous infrared galaxies.

Gr: Geospatial Reality, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

The Space Dynamics Laboratory developed Geospatial Reality (GR), a Government-owned, open software architecture that enhances military/DoD system capability by visually presenting warfighters with tactically relevant, geospatial situational awareness information in real time. GR is designed to facilitate both real-time Augmented Reality (AR) and Virtual Reality (VR) applications on a variety of systems. Most of the underlying software methods are typically the same for both AR and VR and often the location of the operator is the only difference between the two.

Theoretical Paschen's Law Model For Aerospace Vehicles: Validation Experiment, Jaysen Mulligan Aroche

Electronic Theses and Dissertations

Aerospace vehicles often experience triboelectric charging while traversing the atmosphere. Triboelectric charging occurs when a material come into frictional contact with a different material. Aerospace vehicles triboelectrically charge due to frictional contact with dust and ice crystals suspended in the atmosphere. Launch vehicles traversing ice clouds in low-pressure atmosphere are especially prone to electrostatic discharge events (i.e. sparks). These conditions are hazardous and affect the vehicle's launch commit criteria. In 2010, engineers from an ARES-I rocket launch reported concerns with triboelectric charging over their self-destruct system antenna. This concern was addressed by putting the antenna through harsh conditions in a …

The Exploration Of Rotating Detonation Dynamics Incorporating A Coal-Based Fuel Mixture, John P. Rogan

Honors Undergraduate Theses

This investigation explores the detonation dynamics of a rotating detonation engine (RDE). Beginning with the general understanding and characteristics of hydrogen and compressed air as a detonation fuel source, this study further develops the experimental approach to incorporating a coal-based fuel mixture in an RDE. There is insufficient prior research investigating the use of coal as part of a fuel mixture and insignificant progress being made to improve thermal efficiency with deflagration. The U.S. Department of Energy's Office of Fossil Energy awarded the Propulsion and Energy Research Laboratory at the University of Central Florida a grant to lead the investigation …

A Novel Approach For Missing Combat Support Aircraft Search Acceleration Using Vtol Uas, Mohammed Ba Zuhair, Wisam Yousef, Issam Samara, Vladislav Varsegov

International Journal of Aviation, Aeronautics, and Aerospace

In this paper, an approach to accelerate search operations for a missing combat support aircraft using a portable waterproof autonomous vertical takeoff and landing unmanned aerial system called “flying locator beacon” is described. The latter is connected with both flight data and cockpit voice recorders with a parallel bus and may be deployed from the empennage during extreme emergency scenarios, which is detected when few flight parameters are overrun leading to an air crash stimulating behavior. Landing of the flying locator beacon strictly takes place on global latitude and longitude coordinates only of integer values enabling significant minimization of search …

Damage Characterization Of Aircraft Fuselage Using Vibrothermography Technique-Review And Analysis, Abbasali Saboktakin

International Journal of Aviation, Aeronautics, and Aerospace

Vibrothermogrphy is a promising non-destructive technique that uses ultrasonic elastic waves to detect damages and is typically applied in the aerospace and automotive industries. This technique allows for defect selective imaging using thermal waves that are generated by ultrasound waves. In this paper, vibrothermography technique was applied to the aircraft fuselage to detect its damage. The influence of the damage on the temperature distribution at the damage region on the aluminum was investigated by finite element technique. Comprehensive understanding in edge crack in fuselage heating caused by local friction between crack surfaces was obtained.

Dust Control Examination Using Computational Fluid Dynamics Modeling And Laboratory Testing Of Vortecone And Impingement Screen Filters, Ashish R. Kumar

Theses and Dissertations--Mining Engineering

Heavy industries, such as mining, generate dust in quantities that present an occupational health hazard. Prolonged exposure to the respirable dust has been found to result in many irreversible occupational ailments in thousands of miners. In underground mining applications, a variety of scrubbing systems are used to remove dust near the zones of generation. However, the wire-mesh type fibrous screens in the flooded-bed dust scrubbers used on continuous miners, are prone to clogging due to the accumulation of dust particles. This clogging results in a reduced capture efficiency and a higher exposure to the personnel. This research establishes the Vortecone, …

Adaptive Differential Thrust Methodology For Lateral/Directional Stability Of An Aircraft With A Completely Damaged Vertical Stabilizer, Long K. Lu, Kamran Turkoglu

Faculty Publications

This paper investigates the utilization of differential thrust to help a commercial aircraft with a damaged vertical stabilizer in order to regain its lateral/directional stability. In the event of an aircraft losing its vertical stabilizer, the consequential loss of the lateral/directional stability and control is likely to cause a fatal crash. In this paper, an aircraft with a completely damaged vertical stabilizer is investigated, and a unique differential thrust-based adaptive control approach is proposed to achieve a stable flight envelope. The propulsion dynamics of the aircraft is modeled as a system of differential equations with engine time constant and time …

Compressible Turbulent Flame Speed Of Highly Turbulent Standing Flames, Jonathan Sosa

Electronic Theses and Dissertations

This work presents the first measurement of turbulent burning velocities of a highly-turbulent compressible standing flame induced by shock-driven turbulence in a Turbulent Shock Tube. High-speed schlieren, chemiluminescence, PIV, and dynamic pressure measurements are made to quantify flame-turbulence interaction for high levels of turbulence at elevated temperatures and pressure. Distributions of turbulent velocities, vorticity and turbulent strain are provided for regions ahead and behind the standing flame. The turbulent flame speed is directly measured for the high-Mach standing turbulent flame. From measurements of the flame turbulent speed and turbulent Mach number, transition into a non-linear compressibility regime at turbulent Mach …