Engineering Commons^™

Development Of A State-Space Aeroelastic Model Of A Flexible T-Tail Aircraft For Flutter Analysis, Patrick S. Downs

Doctoral Dissertations and Master's Theses

Flutter prediction is an important part of the preliminary design process of any new aircraft. Current analysis methods include coupled fluid structure interaction codes and doublet lattice panel codes. The computation resources and time required for CFD solutions makes them unattractive for preliminary design and doublet lattice models require considerable pre and post processing to provide satisfactory results. Thus, a process for developing an analytical model to facilitate rapid design changes and the implementation of active control systems is the main motivation of this thesis. An analytical model is developed by first deriving the equations of motion of the structure …

Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer

Publications

In order to increase the accuracy of temporal solutions, reduce the computational cost of time marching, and improve the stability associated with collisions for the finite-volume discrete Boltzmann method, an advanced implicit Bhatnagar-Gross-Krook (BGK) collision model using a semi-Lagrangian approach is proposed in this paper. Unlike existing models, in which the implicit BGK collision is resolved either by a temporal extrapolation or by a variable transformation, the proposed model removes the implicitness by tracing the particle distribution functions (PDFs) back in time along their characteristic paths during the collision process. An interpolation scheme is needed to evaluate the PDFs at …

An Analysis Of Self-Reported Sleepiness And Fatigue Measures From Collegiate Aviation Pilots, Flavio A. C. Mendonca, Julius Keller, Thomas Laub, Sarah Wolfe

Publications

Fatigue can be deleterious to pilot performance. The National Transportation Safety Board has called on the aviation community to reduce fatigue related accidents. Currently, there are few studies and guidance specific to collegiate aviation pilots. The current study is part of a larger effort by the authors to gain a clearer understanding of fatigue within the collegiate aviation environment. Collegiate aviation pilots are a unique group with different schedules, lifestyles, and demands when compared to airline, military, and on-demand pilots. The purpose of this study was to examine self-reported fatigue and sleepiness measures. Research instruments included the Karolinska Sleepiness Scale …

Regional Airlines, Benjamin Jones Jr.

Student Works

The airline industry plays a major role in the United States. Many passengers use air transportation as a major mode of traveling for business and personal. As the demand for traveling increased, pilot shortage has increased as well. A pilot shortage will devastate the economy and have a lasting effect that will be felt worldwide. However, sources predict that the United States will experience a sizable pilot shortage over the next few years. This paper will identify the reasons for the pilot shortage and discuss the devastating effects that the shortage has on the regional airline industry. In addition, this …

Airline Quality Rating 2020, Brent D. Bowen, Dean E. Headley

Airline Quality Rating Report

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The results of the 30th annual national Airline Quality Rating (AQR). The most comprehensive study of the performance quality of the 10 largest airlines in the United States, the AQR is conducted by researchers at the W. Frank Barton School of Business at Wichita State University and Embry-Riddle Aeronautical University’s Prescott, Ariz., campus. Airline performance, as presented by AQR researchers, encompasses a multifactor look at the overall quality of the airlines. It includes on-time performance, denied boardings, mishandled baggage and customer complaints. …

Pilot’S Willingness To Operate In Unmanned Aircraft System Integrated Airspace, Lakshmi Vempati

Doctoral Dissertations and Master's Theses

The interest in Unmanned Aircraft Systems (UAS) use for private, civil, and commercial purposes such as package delivery, inspection, surveillance, and passenger and cargo transport has gained considerable momentum. As UAS infiltrate the National Airspace System (NAS), there is a need to not only develop viable, safe, and secure solutions for the co-existence of manned and unmanned aircraft, but also determine public acceptance and pilot’s willingness to operate an aircraft in such an integrated environment. Currently there is little or no research on pilot’s perceptions on their willingness to operate an aircraft in UAS integrated airspace and airports.

The purpose …

Active Drag Reduction Of Ground Vehicles Using Air-Jet Wheel Deflectors, Kaloki Nabutola

Doctoral Dissertations and Master's Theses

Seven turbulence models were used to simulate the flow within the wheelhouse of a simplified vehicle body. The performance of each model was evaluated by comparing the aerodynamic coefficients obtained using computational fluid dynamics (CFD) to data collected from wind tunnel experiments. The performance of large eddy simulation (LES) and detached eddy simulation (DES) was largely dependent on the time step and grid size to accurately resolve turbulent eddies. The standard k-e, realizable k-e, k-w, DES, and LES all trended towards a drag coefficient which was 20% lower than the experimental value. In all numerical cases, the lift coefficient was …

Analysis Of Local Convection Heat Transfer Rates Of Supercritical Carbon Dioxide In Tubes, Yang Chao

Doctoral Dissertations and Master's Theses

Numerical investigation on thermodynamic characteristics of pure supercritical carbon dioxide (𝑆𝐶𝑂2) and mixtures of Helium and 𝑆𝐶𝑂2 in horizontal straight tubes with diameter of 6mm under cooling and heating conditions is carried out by using SST 𝑘 − 𝜔 turbulence model. The computations are conducted at operating pressure of 8MPa with various operating conditions. Simulations are conducted by using the latest poly-hexcore mesh method in ANSYS FLUENT 19.2 and tetrahedral mesh method in CFX 19.2, results and solving time are compared. The effect of heat flux, mass flux, inlet temperature and buoyancy on heat transfer performance are studied, pressure drop …

Dmd And Pod Modal Analysis For Store Separation, Nicholas Peters

Doctoral Dissertations and Master's Theses

Store separation from aircraft and spacecraft has historically been a critical and in some cases fatal issue for the aerospace industry. Given the severity of the issue much effort has been spent on the development of processes to identify failure flight conditions for store separation. The processes currently used for identifying potential failure conditions however are both resource intensive and iterative processes. A potential remedy to reducing resource use and improve turn around time in this process is the implementation of a mode based reduced order model (ROM) for modeling store separation. The objective of this study was to first …

Unsteady Internal Ballistics Of A Hybrid Rocket, Naveen Sri Uddanti

Doctoral Dissertations and Master's Theses

With the recent progress made in the field of space tourism, hybrid rocket engines have gained a renewed interest due to their simplicity, low cost, operational flexibility, and safety. The flow in the ports of a hybrid rocket motor involves several coupled unsteady phenomena like moving walls, combustion in a boundary layer flow and mass addition along the port, through the regression of the solid fuel wall. The flow in the combustion chamber of a hybrid rocket is inherently unsteady because the geometry of the port varies as a function of space and time. In the current research, we develop …

Viscoplastic Study Of 3d Printed Carbon Fiber Composites, Alexander M. Seifans

Doctoral Dissertations and Master's Theses

The research presented here involves an attempt to model the viscoplastic response of 3D printed carbon fiber composites made using the Mark Two 3D printer by Markforged. The ability to manufacture composites through the use of 3D printers is relatively new and contains gaps in the various mechanical properties of the material, of interest is the viscoplastic response.

Due to the fabrication method, the properties of the composites cannot be assumed to be similar to that of conventionally made composites as the fused deposition in printing alters the material properties. In order to understand the effects of the printed fiber …

Shape Optimization Of Microfiber Composite Energy Harvesters, Suyash Lahoti

Doctoral Dissertations and Master's Theses

A model of energy harvesting beam with a piezoelectric material, microfiber composite (MFC), in a unimorph configuration was setup in Matlab using the governing equations of motions of a coupled electromechanical system. The equations of motion were derived using Hamilton’s variational principles and constitutive relations of a piezoelectric material. The mathematical model developed in Matlab was validated with an experiment and frequency response functions. The validated model was used to perform shape optimization so as to obtain the shape of the beam and the patch that harvests the largest voltage. The shape variables were length of the beam (LB), length …

Determinants Of Aviation Students’ Intentions To Use Virtual Reality For Flight Training, Stephanie Gill Fussell

Doctoral Dissertations and Master's Theses

Immersive simulation technology has been incorporated into numerous training environments, including medicine, engineering, and marketing. The aviation industry, in particular, has a history of embracing technology to enhance training and has especially regulated the requirements of devices for flight training. Virtual reality (VR) is the newest technology being adapted for training purposes. Many educational institutions training providers are incorporating virtual environments (VE) and VR systems into curricula and training programs to expand educational opportunities, enhance learning, promote deep cognitive learning, and leverage the abilities of a generation of students who have adopted technology from an early age.

As VR is …

Safety Systems, Culture, And Passengers’ Willingness To Fly In Autonomous Air Taxis, Kenneth Alexander Ward

Doctoral Dissertations and Master's Theses

As city populations grow, the transportation industry plans to alleviate traffic congestion by introducing the urban air mobility (UAM) concept, in which small passenger and cargo aircraft augment metropolitan transportation networks. A key component of UAM is that of air taxis, which are on-demand air services for individuals and small groups. In addition, UAM companies are designing the aircraft to operate fully autonomously: The intent is for the vehicles to arrive and transport people from point to point without input from human pilots.

In studies of passengers’ perceptions, researchers found that safety was among the top passenger concerns. The international …

Studies Of Oval Tube And Fin Heat Exchangers, Phillip Nielsen

Undergraduate Student Works

Heating Ventilation and air-conditioning (HVAC) is a system which changes the temperature of the surroundings for the purposes of cooling or heating. This system requires energy to maintain a temperature difference from the outside temperature. Optimizing the flow over the evaporator coils is one way to increase the cooling efficiency. This will reduce the power required to have a sustainable system. Optimizing the flow to increase the energy transfer between the fins and the incoming air could result in a greater Coefficient of Performance (COP). This will be achieved by changing the geometry of the tubes for greater interaction with …

Aircraft Rescue And Fire Fighting Capabilities: Are Today’S Standards Protecting Passenger’S Futures?, Kaetlyn Blocker

Student Works

Few studies have been conducted that have truly considered the relevance and inadequacies of applicable aircraft rescue and firefighting (ARFF) regulations. Fewer still have studied and explored accident cases that directly exemplify the deficiencies and inconsistencies of various regulatory standards and requirements. This study seeks to expose and explain those inadequacies by utilizing a historical, case-study type research method to examine accident cases during which time the governing regulations played a significant role in the ARFF operations. The findings discovered as a result of this multi-case analysis provide evidence that the current regulations governing United States ARFF operations are both …

Zenith Propulsion, Bryce Smoldon, Matthew Boban, Maxwell Kauker, Jonathan Noble, Stefan Johnson, Andrew Lucka, Nicholas Wright

Undergraduate Student Works

Launch Vehicle Design for the FAR-Mars Competition The Zenith Propulsion team took on the challenge put forth by the Friends of Amateur Rocketry (FAR), to build and launch a rocket propelled by a liquid rocket engine. In 2018-2019, a capstone team called Tiber Designs successfully designed and tested a 1,000 lbf-thrust rocket engine, named Janus, that uses liquid oxygen and jet-A (aviationgrade kerosene) as propellants. Zenith Propulsion would design a vehicle – 21 ft long, 6 in diameter, 170 lbm loaded – that uses the Janus rocket engine to fly to a target altitude of 30,000 ft above ground level. …

Evaluating Scenarios That Can Startle And Surprise Pilots, Rahim Daud Agha

Doctoral Dissertations and Master's Theses

Startle and surprise on the flight deck is a contributing factor in multiple aviation accidents that have been recognized by multiple aviation safety boards. This study identified the effects startle and surprise had on commercial pilots with single and multiengine ratings. Surprise is defined here as something unexpected (e.g., engine failure), while startle is the associated exaggerated effect of an unexpected condition (e.g., thunder sound). Forty pilots were tested in a basic aviation training device configured to a Cessna 172 (single-engine) and a Baron 58 (multi-engine). Each pilot flew the single- and multiengine aircraft in a scenario that induced an …

Supercritical Carbon Dioxide Based Heat Exchanger On The Martian, Sarah Guinn

Discovery Day - Prescott

The use of supercritical carbon dioxide (sCO2) in power cycles has been fairly new in the last decade. Due to this, there is a lack in research for both terrestrial and extraterrestrial applications. The purpose of this project is to utilize sCO2 as a working fluid and design and optimize a Brayton Cycle based heat exchanger on the Martian surface. Due to the lack of water on Mars, this research will provide a stronger analysis of planetary based drycooling processes in low atmospheric pressure and colder temperatures. We have been conducting an in-depth analysis of the heat exchanger by modeling …

Experimental Study On Compression And Shear Strength Of Cfrp, Joseph Gentile, Ethan Garber

Discovery Day - Prescott

The increasing use of carbon fiber-reinforced polymer (CFRP) in the aerospace industry requires a better understanding of its damage properties. Many modern aircraft under high loads are utilizing this material for their primary structures due to its high strength to weight ratio. However, CFRPs are sensitive to out-of-plane loading such as low-velocity impact and indentation. These damages can reduce the compressive strength significantly without leaving a visible mark on the surface, which is known as Barely Visible Impact Damage (BVID). The behavior and residual strength of CFRPs after impact damage under compressive loading are still not fully understood. Studies of …

Arizona Hyperloop: The Fifth Mode Of Transportation, Eleanor Pahl, Matthieu Rada

Discovery Day - Prescott

Arizona Hyperloop is a coalition between Embry-Riddle Aeronautical University and Arizona State University students competing in Elon Musk’s annual SpaceX Hyperloop Pod Competition. Hyperloop is the proposed “Fifth Mode of Transportation” - coined “a cross between a Concorde, a rail gun, and an air hockey table.” A hyperloop pod levitates and travels at nearly the speed of sound inside a vacuum tube, which eliminates air resistance. Musk hosts the annual competition to university students to encourage the evolution of urban transportation. The goal is to design, build, and race the fastest prototype pod at SpaceX’s mile-long test track in Hawthorne, …

Vex U Robotics, Kyle Lutterman, Jeffrey Ryan, Sierra Wong, Elizabeth Geiger

Discovery Day - Prescott

VEX U is a competition hosted by the REC Foundation for university students to get engaged in hands-on engineering. Each team produces two robots using the VEX provided parts to compete in the VEX U competition. The competition changes every year with the only constants being the size of the field, the tools and parts teams are able to use, and the size constraints of the robots. The teams compete in regional competitions in order to qualify for the World Championship Competition, which is the highest competition a team can compete in for VEX U. The VEX U teams at …

Aircraft Leading Edge Strakes On Conventional Naca Wings, Anthony Pirone

Discovery Day - Prescott

The prevention of stall on aircraft wings has been a great challenge over the history of airplanes. As the aircraft become more and more complex, it becomes harder to fit high lift devices and leading-edge devices onto high camber, supercritical airfoil aircraft wings. In the fighter jet class of aircraft the obstacle of stall is usually delayed by the implementation of leading-edge root extensions or strakes. Strakes create a tip vortice along the sharp leading edge that transitions over the surface of the wing preventing separation on both the upper and lower surface of the wing allowing the fighter jet …

Studies Of Oval Tube And Fin Heat Exchangers, Phillip Nielsen

Discovery Day - Prescott

Heating Ventilation and air-conditioning (HVAC) is a system which changes the temperature of the surroundings for the purposes of cooling or heating. This system requires energy to maintain a temperature difference from the outside temperature. This is important since minimized power is one of the requirements for the system to achieve a better efficiency. Optimizing the flow over the evaporator coils is one way to increase the cooling efficiency. This will reduce the power required to have a sustainable system. Optimizing the flow to increase the energy transfer between the fins and the incoming air could result in a greater …

Sae Aero West Heavy Lift Competition Team - Eaglenautics, Anthony Pirone, Evan Stuart, Jessica Millard, Nathaniel Scott

Discovery Day - Prescott

ERAU’s SAE Aero Design West Competition team encourages students of all majors who have an interest in the design of heavy-lift cargo and passenger aircraft to design, build, and fly a large RC aircraft to meet a new set of regulations each competition year. Since the team, Eaglenautics, was founded in 2017 it has successfully been to competition once in April 2019 in California. The team’s aircraft flew 4 out of 5 flight rounds, passed all technical inspections, and is now on display in ERAU’s Aero-Fab in the AXFAB. The 2020 competition requirements are unique in that the cargo’s weight-to-volume …

Tech Comm Eagle Eye-Tracking Control System, Gabiella Lail, Robert Shaw, Hunter Smatla, Matthew Gary

Discovery Day - Prescott

Mobile eye-tracking systems provide usability research support as well as access to a wide range of robotics and technical communication research opportunities. Optical tracking systems are often prohibitively expensive and do not provide the mobility or flexibility needed for a variety of research application possibilities. Our team proposes building a simple mobile eye-tracking system to be used in-house at ERAU for heat-mapping, robotics, control systems, and various technical communication applications in a structured research environment. The mobile eyetracking system will become part of a larger research and hands-on technical communication usability lab and research center. The research team intends to …

7-Dof Robotic Arm Xy-Plane Translational Stability, Christopher Dean Alkire

Doctoral Dissertations and Master's Theses

Robotic arms are traditionally mounted to rigid structures as they perform tasks. As a result, the arm’s movement would not affect the position of its mount and its operational space that it is performing a task within would remain constant. If a robotic arm were to function in orbit, the motion of the arm would cause it to rotate and translate about its center of mass, which changes as the joints of the arm rotate.

The purpose of this thesis is to focus on the two-dimensional translational effects of an arm operating on a simulated zero-friction surface and provide a …

Interaction Of High Aspect-Ratio Micro-Pillars With Wall Turbulence, Pratik Suhas Deshpande

Doctoral Dissertations and Master's Theses

An experimental study of the interaction between hairy structures modeled as high-aspect ratio micro-pillars (HAMuP) and wall turbulence is presented. Micro-pillars are elastic, hair-like microstructures which have been inspired by naturally occurring examples like lateral line sensors in fish and air flow sensors in bats. The objective of this thesis was two fold: to develop a manufacturing process for consistent production of HAMuP arrays, and to conduct a study focusing on the interaction of HAMuP arrays with wall turbulence. Hotwire anemometry measurements were carried out in two different experimental facilities at three different streamwise locations to describe the interaction between …

Constrained Motion Analysis And Control Of Spacecraft Asteroid Hovering With Formulation Extension In Geometric Mechanics Framework, Wesley Thomas Stackhouse

Doctoral Dissertations and Master's Theses

This thesis studies the constrained motion for a spacecraft hovering over an asteroid, where the Udwadia-Kalaba (UK) formulation is applied for nominal control, and an adaptive controller is developed to account for unknowns in the dynamics. Then, the formulation is extended in the geometric mechanics framework to account for rigid body spacecraft asteroid hovering. Constraints are developed and applied for fully constrained and under-constrained asteroid hovering. The fully constrained solutions provided by the UK fundamental equation are compared to an optimal linear quadratic regulator. An adaptive controller is designed using the UK fundamental equation as a basis in the form …

Communication Status Of Aircraft And Near Midair Collision Occurrences, H. E. Mcnevin

Graduate Student Works

The purpose of this research is to examine instances of near mid-air collision (NMAC) in order to determine if the number of instances of traffic conflictions resulting in near mid-air collision situations while in contact with air traffic control is rising over the last decade. Midair collision and near midair collision situations between aircraft operating while at least one is talking to air traffic control (ATC) present a hazard to safety and with the potential for a deadly encounter that results in loss of life and damage to property. Situations such as this in the National Airspace System (NAS) involve …