Aerospace Engineering Commons^™

Numerical Algorithm For Wing-Structure Design, Jeffrey D. Taylor, Douglas F. Hunsaker, James J. Joo

Mechanical and Aerospace Engineering Student Publications and Presentations

Low-fidelity aerostructural optimization routines have often focused on determining the optimal spanloads for a given wing configuration. Several analytical approaches have been developed that can predict optimal lift distributions on rectangular wings with a specific payload distribution. However, when applied to wings of arbitrary geometry and payload distribution, these approaches fail. Increasing the utility and accuracy of these analytical methods can result in important benefits during later design phases. In this paper, an iterative algorithm is developed that uses numerical integration to predict the distribution of structural weight required to support the bending moments on a wing with arbitrary geometry …

Investigation Into Reynolds Number Effects On A Biomimetic Flapping Wing, Daniel K. Hope, Anthony M. Deluca, Ryan P. O'Hara

Faculty Publications

This research investigated the behavior of a Manduca sexta inspired biomimetic wing as a function of Reynolds number by measuring the aerodynamic forces produced by varying the characteristic wing length and testing at air densities from atmospheric to near vacuum. A six degree of freedom balance was used to measure forces and moments, while high speed cameras were used to measure wing stroke angle. An in-house created graphical user interface was used to vary the voltage of the drive signal sent to the piezoelectric actuator which determined the wing stroke angle. The Air Force Institute of Technology baseline 50 mm …

Analytical Cpg Model Driven By Limb Velocity Input Generates Accurate Temporal Locomotor Dynamics, Sergiy Yakovenko, Anton Sobinov, Valeriya Gritsenko

Faculty & Staff Scholarship

The ability of vertebrates to generate rhythm within their spinal neural networks is essential for walking, running, and other rhythmic behaviors. The central pattern generator (CPG) network responsible for these behaviors is well-characterized with experimental and theoretical studies, and it can be formulated as a nonlinear dynam- ical system. The underlying mechanism responsible for locomotor behavior can be expressed as the process of leaky integration with resetting states generating appropriate phases for changing body velocity. The low-dimensional input to the CPG model generates the bilateral pattern of swing and stance modulation for each limb and is consistent with the desired …

Fabrication And Thermoelectric Characterization Of Transition Metal Silicide-Based Composite Thermocouples, Gunes A. Yakaboylu, Rajalekshmi C. Pillai, Katarzyna Sabolsky, Edward M. Sabolsky

Faculty & Staff Scholarship

Metal silicide-based thermocouples were fabricated by screen printing thick films of the powder compositions onto alumina tapes followed by lamination and sintering processes. The legs of the embedded thermocouples were composed of composite compositions consisting of MoSi2, WSi2, ZrSi2, or TaSi2 with an additional 10 vol % Al2O3 to form a silicide–oxide composite. The structural and high-temperature thermoelectric properties of the composite thermocouples were examined using X-ray diffraction, scanning electron microscopy and a typical hot–cold junction measurement technique. MoSi2-Al2O3 and WSi2-Al2O3 composites exhibited higher intrinsic Seebeck coefficients (22.2–30.0 μV/K) at high-temperature gradients, which were calculated from the thermoelectric data of …

Interval Fuzzy Model For Robust Aircraft Imu Sensors Fault Detection, Michele Crispoltoni, Mario Luca Fravolini, Fabio Balzano, Stephane D'Urso, Marcello Rosario Napolitano

Faculty & Staff Scholarship

This paper proposes a data-based approach for a robust fault detection (FD) of the inertial measurement unit (IMU) sensors of an aircraft. Fuzzy interval models (FIMs) have been introduced for coping with the significant modeling uncertainties caused by poorly modeled aerodynamics. The proposed FIMs are used to compute robust prediction intervals for the measurements provided by the IMU sensors. Specifically, a nonlinear neural network (NN) model is used as central prediction of the sensor response while the uncertainty around the central estimation is captured by the FIM model. The uncertainty has been also modelled using a conventional linear Interval Model …

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 …

Electrostatic Potential And Valence Modulation In La0.7sr0.3mno3 Thin Films, Robbyn Trappen, A. C. Garcia- Castro, Vu Thanh Tra, Chih-Yeh Huang, Wilfredo Ibarra-Hernandez, James Fitch, Sobhit Singh, Jingling Zhou, Guerau Cabrera, Ying-Hao Chu, James M. Lebeau, Aldo H. Romero, Mikel B. Holcomb

Faculty & Staff Scholarship

The Mn valence in thin film La0.7Sr0.3MnO3 was studied as a function of film thickness in the range of 1–16 unit cells with a combination of non-destructive bulk and surface sensitive X-ray absorption spectroscopy techniques. Using a layer-by-layer valence model, it was found that while the bulk averaged valence hovers around its expected value of 3.3, a significant deviation occurs within several unit cells of the surface and interface. These results were supported by first principles calculations. The surface valence increases to up to Mn3.7+, whereas the interface valence reduces down to Mn2.5+. The change in valence from the expected …

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

Aviation Department Publications

No abstract provided.

Relationship Between Airline Category, Geographical Region, And Safety Performance, Peter Simpson

Walden Dissertations and Doctoral Studies

Passengers rank safety as a key factor in airline choice. Thus, safety performance impacts an airline's ability to attract customers. The purpose of this correlational study was to examine the relationship and difference between airline category low-cost carriers (LCCs) and full-service carriers (FSCs), geographical region, and safety performance measured by accident rates. The target population comprised all airlines in all countries that had an accident during the 14-year period 2004 to 2017. Data consisted of archival data of all global airline accidents and airline departure frequencies for the 14-year period. The theory of organizational accidents in complex sociotechnical systems explains …