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Articles 3901 - 3930 of 11196
Full-Text Articles in Aerospace Engineering
Dmd And Pod Modal Analysis For Store Separation, Nicholas Peters
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
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
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 …
Post-Impact Flexural Behavior Of Carbon-Aramid/Epoxy Hybrid Composites, A. Wagih, T. A. Sebaey, A. Yudhanto, G. Lubineau
Post-Impact Flexural Behavior Of Carbon-Aramid/Epoxy Hybrid Composites, A. Wagih, T. A. Sebaey, A. Yudhanto, G. Lubineau
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Hybrid polymeric composites are currently used in aerospace structures due to their specific strength and stiffness as well as larger design space. This paper presents an experimental study on residual flexural strength of impacted Carbon-aramid/Epoxy hybrid composite laminates. Specimens are designed in a sandwich form in which plies of aramid/epoxy represent the core and carbon/epoxy plies play the role of face sheets. This design is expected to take advantage of the high energy absorption capabilities of aramid/epoxy composites. We pre-damage such composites by performing low-velocity impact at different energy levels. Three-point bending tests then are used to measure the residual …
Use Of Garmin Autopilot Envelope Protection System For Simplified Vehicle Operations In General Aviation, Stephen Sullivan
Use Of Garmin Autopilot Envelope Protection System For Simplified Vehicle Operations In General Aviation, Stephen Sullivan
Theses and Dissertations
The general aviation industry suffers from high rates of fatalities and accidents occurring due to loss of control while in flight. This thesis research aims to implement a simple yet effective simplified vehicle operations (SVO) scheme that uses a Garmin autopilot system to create a pilot-on-the-loop controller to help prevent loss of control incidents from occurring. With this scheme, the pilot is controlling turns and climb rates instead of elevator and aileron deflections and is protected from the risk of under-speed and stall through the Garmin autopilots built-in limits. To interface with the autopilot system, a Raspberry Pi and Pythonbased …
Towards Gross-Pitaevskiian Description Of Solar System & Galaxies, Florentin Smarandache, Victor Christianto, Yunita Umniyati
Towards Gross-Pitaevskiian Description Of Solar System & Galaxies, Florentin Smarandache, Victor Christianto, Yunita Umniyati
Branch Mathematics and Statistics Faculty and Staff Publications
In this paper, we argue that Gross-Pitaevskii model can be a more complete description of both solar system and spiral galaxies, especially taking into account the nature of chirality and vortices in galaxies. We also hope to bring out some correspondence among existing models, e.g., the topological vortex approach, Burgers equation in the light of KAM theory, and the Cantorian Navier-Stokes approach. We hope further investigation can be done around this line of approach.
Flight Path Control During Hypersonic Atmospheric Entry Using Active Magnetic Arrays, Matthew Tyler Austin
Flight Path Control During Hypersonic Atmospheric Entry Using Active Magnetic Arrays, Matthew Tyler Austin
Theses and Dissertations
The purpose of this thesis is to study the reaction to the Lorentz force induced during the hypersonic regime of flight by an active magnetic field. The effect that a magnetic array has on the flight characteristics of a blunt body during Earth atmospheric entry is characterized and isolated for independent analysis. This is done to show that mission-specific benefits to utilizing this method of entry control exist and therefore warrant further study. To conduct this analysis, a 1000 kg blunt body test case was used. This craft contains three separate magnets located behind the nose with two of them …
Flight Testing Of The Piper J4a Cub Coupe, Kenneth Burton Connick
Flight Testing Of The Piper J4a Cub Coupe, Kenneth Burton Connick
Theses and Dissertations
Flight testing is an important part of in the airplane design process. This testing is performed to ensure that the airplane complies with the established requirements and regulations for flight safety, as well as to ensure it meets its mission objectives. The Federal Aviation Administration (FAA) currently governs these requirements and regulations for civilian aircraft and provides airworthiness certifications. The FAA regulations were introduced in 1965. Prior to that, civilian aircraft were certified through the Civil Aeronautics Administration using Civil Air Regulations (CARs).
Change Of Exposure Time Mid-Test In High Temperature Dic Measurement, Thinh Quang Thai, Adam J. Smith, Robert J. Rowley, Paul R. Gradl, Ryan B. Berke
Change Of Exposure Time Mid-Test In High Temperature Dic Measurement, Thinh Quang Thai, Adam J. Smith, Robert J. Rowley, Paul R. Gradl, Ryan B. Berke
Mechanical and Aerospace Engineering Faculty Publications
Performing digital image correlation (DIC) at extreme temperatures has been greatly challenging due to the radiation which saturates the camera sensor. At such high temperatures, the light intensity emitted from an object is occasionally so powerful that the acquired images are overwhelmingly saturated. This induces data loss, potentially ruining the test, thus requiring the user to restart the test. For this reason, selection of an appropriate camera sensitivity plays a crucial role prior to beginning the test. Exposure time is a factor contributing to camera sensitivity and it is the easiest setting to manipulate during the test since it introduces …
Zenith Propulsion, Bryce Smoldon, Matthew Boban, Maxwell Kauker, Jonathan Noble, Stefan Johnson, Andrew Lucka, Nicholas Wright
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. …
Urban Cargo Transport Uav Final Design Review, Niko Giannakakos, Rafael Barreto Gutierrez, Tejas Bhavsar
Urban Cargo Transport Uav Final Design Review, Niko Giannakakos, Rafael Barreto Gutierrez, Tejas Bhavsar
Senior Design Project For Engineers
Delivery of goods to homes and offices over the last decades has seen a significant increase as more people and businesses need or want items sent directly to them. With the increase in demand, technology has also experienced a rapid growth, specifically in the field of unmanned aerial vehicles (UAVs). Many major companies are currently researching UAVs as the future of their delivery operations. With this ever-growing demand, NASA has issued a design competition of a UAV developed for urban deliveries. This unmanned aircraft system (UAS) would need to be able to deliver small packages, in a timely manner, within …
Aerial Screw Vtol Rotorcraft, Macale Rielly, Alexa Culp, Thomas Osteen, Adeline Perry
Aerial Screw Vtol Rotorcraft, Macale Rielly, Alexa Culp, Thomas Osteen, Adeline Perry
Senior Design Project For Engineers
Known as the “Renaissance Man,” DaVinci’s impressive knowledge of mechanics and inventive prowess would influence engineers and innovators hundreds of years later to make human flight a reality. However, due to the limited capacity of engineering and manufacturing at the time, his invention had been shallowly investigated in a production setting. This project strove to properly acknowledge DaVinci’s invention by thorough examination and critical analysis of his concept with the hopes of gaining a better understanding of why it is considered the “foundation of vertical flight”.
An iterative design approach was employed, utilizing faculty and university resources, team knowledge from …
Linear Covariance Navigation Analysis Of Range And Image Measurement Processing For Autonomous Lunar Lander Missions, Randall Christensen, David Geller, Michael Hansen
Linear Covariance Navigation Analysis Of Range And Image Measurement Processing For Autonomous Lunar Lander Missions, Randall Christensen, David Geller, Michael Hansen
Space Dynamics Laboratory Publications
Growing interest in autonomous landing on the lunar surface has motivated in-depth studies of the navigation architectures to support such missions. The research presented in this paper extends linear covariance models of terrain-relative navigation architectures to incorporate both image-based measurements to known landmarks and laser range measurements to the lunar surface. The benefit of the range measurements is shown to be significant in reducing relative position and velocity errors in the altitude channel, as compared to an image-only navigation architecture. The range measurements are also shown to reduce the sensitivity of final relative navigation errors to the turn-on time of …
A Numerical Investigation Of Microgravity Evaporation, Daniel Peter Ringle
A Numerical Investigation Of Microgravity Evaporation, Daniel Peter Ringle
Dissertations and Theses
Evaporation is important to myriad engineering processes such as cooling, distillation, thin film deposition, and others. In fact, NASA has renewed interest in using cabin air pressure evaporation as a means to recycle waste water in space. As one example, NASA recently conducted experiments aboard the International Space Station (ISS) to measure evaporation rates in microgravity and to determine the impacts of porous structure on the process. It has long been assumed that differences in evaporation rates between 1-g0 and microgravity are small. However, discrepancies by as much as 40% have been observed in practice. The assumption now …
Supercritical Carbon Dioxide Based Heat Exchanger On The Martian, Sarah Guinn
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 …
Thermal Modeling Of Additive Manufacturing Using Graph Theory: Validation With Directed Energy Deposition, Jordan Severson
Thermal Modeling Of Additive Manufacturing Using Graph Theory: Validation With Directed Energy Deposition, Jordan Severson
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Metal additive manufacturing (AM/3D printing) offers unparalleled advantages over conventional manufacturing, including greater design freedom and a lower lead time. However, the use of AM parts in safety-critical industries, such as aerospace and biomedical, is limited by the tendency of the process to create flaws that can lead to sudden failure during use. The root cause of flaw formation in metal AM parts, such as porosity and deformation, is linked to the temperature inside the part during the process, called the thermal history. The thermal history is a function of the process parameters and part design.
Consequently, the first step …
Investigation Of Navigation Systems For Size, Cost, And Mass Constrained Satellites, Omar Awad
Investigation Of Navigation Systems For Size, Cost, And Mass Constrained Satellites, Omar Awad
USF Tampa Graduate Theses and Dissertations
The feasibility of using radically inexpensive micro-electromechanical system (MEMS) technology for navigation of a nanosatellite is investigated with a focus on attitude estimation. Typically, larger satellites are equipped with star cameras, sun sensors, or Earth horizon sensors for attitude estimation. These sensors can provide very accurate attitude measurements. A nanosatellite is highly size, power, and cost constrained and cannot readily accommodate these sensors. Our mission is to design, build, and operate a radically inexpensive nanosatellite system. While there is no consensus on what constitutes a "radically inexpensive" satellite, our goal is a maximum cost of $10,000 per unit. This precludes …
Experimental Study On Compression And Shear Strength Of Cfrp, Joseph Gentile, Ethan Garber
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 …
Nonlinear Least Squares 3-D Geolocation Solutions Using Time Differences Of Arrival, Michael V. Bredemann
Nonlinear Least Squares 3-D Geolocation Solutions Using Time Differences Of Arrival, Michael V. Bredemann
Mathematics & Statistics ETDs
This thesis uses a geometric approach to derive and solve nonlinear least squares minimization problems to geolocate a signal source in three dimensions using time differences of arrival at multiple sensor locations. There is no restriction on the maximum number of sensors used. Residual errors reach the numerical limits of machine precision. Symmetric sensor orientations are found that prevent closed form solutions of source locations lying within the null space. Maximum uncertainties in relative sensor positions and time difference of arrivals, required to locate a source within a maximum specified error, are found from these results. Examples illustrate potential requirements …
Aerodynamics Of Wind Loading On Buildings, Kayla Burch
Aerodynamics Of Wind Loading On Buildings, Kayla Burch
Honors Theses
A three-dimensional model of a one-story residential home, with an emphasis on the roof style and structure, was modeled using CATIA and then built and tested in the wind tunnel at Western Michigan University. The wind tunnel allowed an airflow over different style roofs to be tested at 100 mile per hour winds, strengths typical for hurricanes and other natural phenomena. The measured results show the lift and drag, along with the pressure gradient and the skin friction over the roofs. The effect of these aerodynamic characteristics of the building due to adding solar panel prototypes were also evaluated. The …
Quantifying Wicking In Functionlized Surfaces, Maureen Winter, Ryan Regan, Alfred Tsubaki, Craig Zuhlke, Dennis Alexander, George Gogos
Quantifying Wicking In Functionlized Surfaces, Maureen Winter, Ryan Regan, Alfred Tsubaki, Craig Zuhlke, Dennis Alexander, George Gogos
UCARE: Research Products
Wicking remains the enigmatic key factor in many research areas. From boiling in power plants, to anti-icing on plane wings, to medical instruments, to heat pipes, efficiency and safety depend on how quickly a surface becomes wet. Yet wicking remains difficult to quantify and define as a property of the surface. This experiment strives to measure the wicking property by examining the rate that a liquid can be pulled out of a container. A superhydrophilic surface is placed in contact with the liquid at the bottom of a tube so that the volume flow rate across the surface can be …
Nytrox As “Drop-In” Replacement For Gaseous Oxygen In Smallsat Hybrid Propulsion Systems, Stephen A. Whitmore
Nytrox As “Drop-In” Replacement For Gaseous Oxygen In Smallsat Hybrid Propulsion Systems, Stephen A. Whitmore
Mechanical and Aerospace Engineering Faculty Publications
A medical grade nitrous oxide (N2O) and gaseous oxygen (GOX) “Nytrox” blend is investigated as a volumetrically-efficient replacement for GOX in SmallSat-scale hybrid propulsion systems. Combined with 3-D printed acrylonitrile butadiene styrene (ABS), the propellants represent a significantly safer, but superior performing, alternative to environmentally-unsustainable spacecraft propellants like hydrazine. In a manner analogous to the creation of soda-water using dissolved carbon dioxide, Nytrox is created by bubbling GOX under pressure into N2O until the solution reaches saturation. Oxygen in the ullage dilutes N2O vapor and increases the required decomposition energy barrier by several orders …
Arizona Hyperloop: The Fifth Mode Of Transportation, Eleanor Pahl, Matthieu Rada
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, …
Aircraft Leading Edge Strakes On Conventional Naca Wings, Anthony Pirone
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 …
Sae Aero West Heavy Lift Competition Team - Eaglenautics, Anthony Pirone, Evan Stuart, Jessica Millard, Nathaniel Scott
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 …
Design, Construction And Testing Of A 3-Component Force Balance For Educational Wind Tunnels In Undergraduate Aerodynamics, Milan Tomin, Marco Scipioni, Benjamin Gatti
Design, Construction And Testing Of A 3-Component Force Balance For Educational Wind Tunnels In Undergraduate Aerodynamics, Milan Tomin, Marco Scipioni, Benjamin Gatti
Journal of Aviation/Aerospace Education & Research
This article is focused on providing detailed instructions on how to build and use a force balance for educational wind tunnels. The article’s objective is to encourage undergraduate students in underfunded programs to engage in the field of aerodynamics. The discussed force balance represents an affordable device that only requires basic components like Arduino board, a servo motor, and acrylic and aluminum as construction materials. A simple data collection example is included at the end of the article showing that this simple force balance can collect meaningful data about lift, drag, and moment coefficient of a tested airfoil.
Numerical Investigation Of Leading-Edge Modifications Of A Naca Airfoil, Anisur Rahman Ikram
Numerical Investigation Of Leading-Edge Modifications Of A Naca Airfoil, Anisur Rahman Ikram
Masters Theses
A parametric investigation was carried out to understand the flow characteristics of tubercle airfoils and to determine the best approach and parameters for designing a tubercle airfoil. For this purpose, a straight edge base airfoil (NACA 4414) and several tubercle airfoils, by modifying the leading edge of the base airfoil, were created in SolidWorks and tested with Computational Fluid Dynamics (CFD) application software Star CCM+.
Alternative tubercle airfoil with elliptical bumps demonstrated superior post-stall performance when compared to their straight edge counterparts; their post-stall lift did not decrease drastically. However, their pre-stall lift coefficients were always lower than the base …
Rotorcraft Blade Angle Calibration Methods, Brian David Calvert Jr.
Rotorcraft Blade Angle Calibration Methods, Brian David Calvert Jr.
Mechanical & Aerospace Engineering Theses & Dissertations
The most vital system of a rotorcraft is the rotor system due to its effects on the overall flight quality of the vehicle. Therefore, it is of importance to be able to accurately determine blade position during flight so that fine adjustments can be made to ensure a safe and efficient flight. In this study, a current calibration method focusing on the pitch, flap, and lead-lag blade angles is analyzed and found to have larger than acceptable error associated with the sensor calibrations. A literature review is conducted which reveals four novel methods that can potentially increase the accuracy of …
Through-Thickness Reinforcement And Repair Of Carbon Fiber Based Honeycomb Structures Under Flexure And Tension Of Adhesively Bonded Joints, Aleric Alden Sanders
Through-Thickness Reinforcement And Repair Of Carbon Fiber Based Honeycomb Structures Under Flexure And Tension Of Adhesively Bonded Joints, Aleric Alden Sanders
Mechanical & Aerospace Engineering Theses & Dissertations
Repair and reinforcement of composite honeycomb structures is an area of concern as higher demands are being placed on high strength, lightweight structural materials, such as carbon fiber reinforced plastics and corresponding honeycomb structures. A common issue with these structures is when a delamination in the facesheet may form and spread, leading to a failure scenario. An investigation of adding a through thickness reinforcement (TTR) to these structures at the sample level that undergo four-point-bending, tension, and joining methods is conducted throughout this thesis. The embedding of pultruded carbon fiber rods is found to be an ideal addition to composite …
Nonlinearity Index Aircraft Spin Motion Analysis With Dynamic Inversion Spin Recovery Controller Design, Jeffry Walker
Nonlinearity Index Aircraft Spin Motion Analysis With Dynamic Inversion Spin Recovery Controller Design, Jeffry Walker
Mechanical & Aerospace Engineering Theses & Dissertations
The aim of this thesis research is to extend the previous work of Tapolcai utilizing nonlinearity index theory to quantitatively analyze nonlinearities in an aircraft model and to augment these undesirable nonlinear characteristics with feedback control. In his work Tapolcai utilized a simplified rotational three degree of freedom model to analyze spin conditions of the F-18 High Angle-of-Attack Research Vehicle model. Through the application of nonlinearity index theory, regions of severe nonlinearity were uncovered exhibiting chaotic non-periodic behavior, periodic limit cycling, and instability. If these conditions were encountered during flight, the aircraft would exhibit undesirable response characteristics thereby requiring augmented …