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Articles 6331 - 6360 of 11135
Full-Text Articles in Engineering
Aerodynamic And Structural Design Of A Winglet For Enhanced Performance Of A Business Jet, Nicolas El Haddad
Aerodynamic And Structural Design Of A Winglet For Enhanced Performance Of A Business Jet, Nicolas El Haddad
Doctoral Dissertations and Master's Theses
The preliminary design of a winglet to improve the range and fuel burn of the Falcon 10 business jet is presented. Twelve candidate geometries were studied varying the cant angle and the span. The configuration offering the best compromise between induced drag reduction, profile drag increase and weight increase due to the winglet structure and necessary wing structural reinforcement was selected. More refined analysis was performed for that winglet with Reynolds averaged Navier-Stokes computational fluid dynamics and finite element analysis. Range and fuel burn were finally calculated for a typical mission using these refined results. The selected winglet, with a …
Attitude Determination & Control System Design And Implementation For A 6u Cubesat Proximity Operations Mission, Francisco J. Franquiz
Attitude Determination & Control System Design And Implementation For A 6u Cubesat Proximity Operations Mission, Francisco J. Franquiz
Doctoral Dissertations and Master's Theses
The purpose of this work is to discuss the attitude determination and control system (ADCS) design process and implementation for a 12 kg, 6U (36.6 cm x 23.9 cm x 27.97 cm) CubeSat class nano-satellite. The design is based on the requirements and capabilities of the Application for Resident Space Object Proximity Analysis and IMAging (ARAPAIMA) proximity operations mission. The satellite is equipped with a cold gas propulsion system capable of exerting 2.5 mN m torques in both directions about each body axis. The attitude sensors include an angular rate gyro and star tracker (STR), supplemented by the payload optical …
Synthetic Aperture Radar: Rapid Detection Of Target Motion In Matlab, Daniel S. Kassen
Synthetic Aperture Radar: Rapid Detection Of Target Motion In Matlab, Daniel S. Kassen
Master's Theses
Synthetic Aperture Radar (SAR) has come into widespread use in several civilian and military applications. The focus of this paper is the military application of imaging point targets captured by an airborne SAR platform. Using the traditional SAR method of determining target motion by analyzing the difference between subsequent images takes a relatively large amount of processing resources. Using methods in this thesis, target motion can be estimated before even a single image is obtained, reducing the amount of time and power used by a significantly large amount. This thesis builds on work done by Brain Zaharri and David So. …
Experimental Investigation Of Drag Reduction By Trailing Edge Tabs On A Square Based Bluff Body In Ground Effect, Scott R. Sawyer
Experimental Investigation Of Drag Reduction By Trailing Edge Tabs On A Square Based Bluff Body In Ground Effect, Scott R. Sawyer
Master's Theses
This thesis presents an experimental investigation of drag reduction devices on a bluff body in ground effect. It has previously been shown that the addition of end-plate tabs to a rectangular based bluff body with an aspect ratio of 4 is effective in eliminating vortex shedding and reducing drag for low Reynolds number flows. In the present study a square based bluff body, both with and without tabs, will be tested under the same conditions, except this time operating within proximity to a ground plane in order to mimic the properties of bounded aerodynamics that would be present for a …
Techno-Economic Feasibility And Life Cycle Assessment Of Dairy Effluent To Biofuel Via Hydrothermal Liquefaction, Hailey M. Summers
Techno-Economic Feasibility And Life Cycle Assessment Of Dairy Effluent To Biofuel Via Hydrothermal Liquefaction, Hailey M. Summers
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Delactosed whey permeate (delac) is a low valued by-product in the dairy industry with 90 million tons annually disposed of worldwide. Upgrading delac to bioproducts, specifically biofuel, has been demonstrated at laboratory scale through yeast fermentation. However, the large-scale environmental impact and economic feasibility of this process is yet to be quantified. Further research, focused on evaluating the sustainability, scalability and economic feasibility of the fermentation pathway, directs research and development to move the technology towards commercialization. The enclosed research incorporates biological experimentation with engineering systems modeling to evaluate the large-scale environmental impacts and economic feasibility of generating bioproducts from …
Methods Of Processing Kenaf Chopped Strand Mats For Manufacturing Test Specimens And Composite Structures, Joshua W. Heil
Methods Of Processing Kenaf Chopped Strand Mats For Manufacturing Test Specimens And Composite Structures, Joshua W. Heil
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Every year in the United States, 10 to 11 million vehicles reach the end of their life cycle. Nearly all of these go to a recycling facility. After the recycling process is complete an average of 25% of each vehicle, by weight, goes to waste. This demonstrates the need to use natural fibers in parts that could be recycled, like parts that can be made from kenaf. There are many reasons to consider using natural/bio-fiber composites (bio-composites). These reasons include human health and environmental factors as well as advantages that natural fibers have over fiberglass, such as: lower costs and …
Computational Fluid Dynamics Simulations Of Oscillating Wings And Comparison To Lifting-Line Theory, Megan Keddington
Computational Fluid Dynamics Simulations Of Oscillating Wings And Comparison To Lifting-Line Theory, Megan Keddington
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Computational fluid dynamics (CFD) analysis was performed in order to compare the solutions of oscillating wings with Prandtl’s lifting-line theory. Quasi-steady and steady-periodic simulations were completed using the CFD software Star-CCM+. Quasi-steady simulations were completed for both twodimensional and three-dimensional setups. The steady-periodic simulations were only performed using a three-dimensional setup. The simulations were performed for nine separate frequencies in a pure plunging setup. An additional four simulations were then completed using a setup of combined pitching and plunging at four separate frequencies. Results from the CFD simulations were compared to the quasi-steady lifting-line solution in the form of the …
Parameterized Least-Squares Attitude History Estimation And Magnetic Field Observations Of The Auroral Spatial Structures Probe, Ryan J. Martineau
Parameterized Least-Squares Attitude History Estimation And Magnetic Field Observations Of The Auroral Spatial Structures Probe, Ryan J. Martineau
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
As charged particles from the Sun enter the Earth’s atmosphere and create the aurora borealis (Northern lights) and aurora australis (Southern lights), energy is transferred to the atmosphere. In order to better understand the energy transfer processes, the Auroral Spatial Structures Probe rocket was launched to make measurements in the active aurora. Several payloads were deployed by the rocket, each with sensors to measure the magnetic field and the electric field so that the way they change over time and in different positions could be observed. The measurements require accurate knowledge of the spacecraft orientation, and to that end this …
High Regression Rate Hybrid Rocket Fuel Grains With Helical Port Structures, Sean D. Walker
High Regression Rate Hybrid Rocket Fuel Grains With Helical Port Structures, Sean D. Walker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Hybrid Rockets are popular in the aerospace industry due to their storage safety, simplicity, and controllability during rocket motor burn. However, they produce fuel regression rates typically 25% lower than solid fuel motors of the same thrust level. These lowered regression rates produce unacceptably high oxidizer-to-fuel (O/F) ratios that produce a potential for motor instability, nozzle erosion, and reduced motor duty cycles. To achieve O/F ratios that produce acceptable combustion charactersitics, traditional cylindrical fuel ports are fabricated with very long length-to-diameter ratios to increase the total burning area. these high aspect ratios produce further reduced fuel regression rate and trust …
Direct Electrical Arc Ignition Of Hybrid Rocket Motors, Michael I. Judson Jr.
Direct Electrical Arc Ignition Of Hybrid Rocket Motors, Michael I. Judson Jr.
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Hybrid rockets motors provide distinct safety advantages when compared to traditional liquid or solid propellant systems, due to the inherent stability and relative inertness of the propellants prior to established combustion. As a result of this inherent propellant stability, hybrid motors have historically proven difficult to ignite. State of the art hybrid igniter designs continue to require solid or liquid reactants distinct from the main propellants. These ignition methods however, reintroduce to the hybrid propulsion system the safety and complexity disadvantages associated with traditional liquid or solid propellants. The results of this study demonstrate the feasibility of a novel direct …
A Neural Network Approach To Fault Detection In Spacecraft Attitude Determination And Control Systems, John N. Schreiner
A Neural Network Approach To Fault Detection In Spacecraft Attitude Determination And Control Systems, John N. Schreiner
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
CubeSats are employed in a variety of missions as scientific platforms, low-cost technology demonstrators, and in the future, they will conduct service missions as part of larger satellite constellations. CubeSat ADCS designers today are being tasked with designing to ever increasing accuracy requirements. The ability to hold those requirements rests with the attitude control system being robust enough and able to sufficiently respond to changes in the control environment. The need for greater control autonomy is then evident in the need for these systems to be able to react independently to changes in the system dynamics and to identify and …
Mapping Regional Inundation With Spaceborne L-Band Sar, Bruce Chapman, Kyle Macdonald, Masanobu Shimada, Ake Rosenqvist, Ronny Schroeder, Laura Hess
Mapping Regional Inundation With Spaceborne L-Band Sar, Bruce Chapman, Kyle Macdonald, Masanobu Shimada, Ake Rosenqvist, Ronny Schroeder, Laura Hess
Publications and Research
Shortly after the launch of ALOS PALSAR L-band SAR by the Japan Space Exploration Agency (JAXA), a program to develop an Earth Science Data Record (ESDR) for inundated wetlands was funded by NASA. Using established methodologies, extensive multi-temporal L-band ALOS ScanSAR data acquired bi-monthly by the PALSAR instrument onboard ALOS were used to classify the inundation state for South America for delivery as a component of this Inundated Wetlands ESDR (IW-ESDR) and in collaboration with JAXA’s ALOS Kyoto and Carbon Initiative science programme. We describe these methodologies and the final classification of the inundation state, then compared this with results …
Investigations Of Synthetic Fuels: S8 And Sasol Ipk To Determine The Possibility Of Alternate Fuels In The Aerospace Industry, Scott M. Dyke
Investigations Of Synthetic Fuels: S8 And Sasol Ipk To Determine The Possibility Of Alternate Fuels In The Aerospace Industry, Scott M. Dyke
GS4 Student Scholars Symposium
Investigations of Synthetic Fuels: S8 and Sasol IPK to Determine the Possibility of Operation as Alternate Fuels in the Aerospace Industry
Name: Scott Dyke
Co-Authors: Martin Muinos, Julia Heimberger, Dr. Valentin Soloiu,
An ever-growing society that becomes more and more dependent on a finite energy source will eventually exceed its supply. Fossil fuel quantities are continuously decreasing and new solutions are needed. According to the United States Department of Transportation, over 10 billion gallons of airline fuels have been consumed in each of the past 15 years with some years over 13 billion gallons. In the meantime, fuel costs have …
Design And Analysis Of A Labview And Arduino-Based Automatic Solar Tracking System, Caiwen Ding
Design And Analysis Of A Labview And Arduino-Based Automatic Solar Tracking System, Caiwen Ding
Morehead State Theses and Dissertations
A Thesis Presented to the Faculty of the College of Science and Technology Morehead State University in Partial Fulfillment of the requirements for the Degree Master of Science by Caiwen Ding April 24, 2015
Simulation Of Complex Ionic Liquid Ionization Process, Forrest Grady Kidd Iii
Simulation Of Complex Ionic Liquid Ionization Process, Forrest Grady Kidd Iii
Research and Creative Activities Poster Day
The future of satellites will require dual-mode propulsion to obtain dynamic orbits. One set of propellants capable of dual-mode propulsion are ionic liquids. These energy-dense liquids have similar thrust characteristics to SOTA monopropellants and low vapor pressures making them safer to handle. That low vapor pressure makes ionization more difficult as it requires the propellant to be in a gaseous state. This requires experiments to determine how to efficently vaporize and ionize this propellant. Computational modelling is needed to guide these experiments and to develop simulations that can extrapolate the data to more complex geometries.
Unstandard Cubesat/Pocketqube/Tubesat Deployers, Robert J. Twiggs
Unstandard Cubesat/Pocketqube/Tubesat Deployers, Robert J. Twiggs
Robert "Bob" Twiggs STEM Education Collection
A PowerPoint presentation created by Professor Bob Twiggs titled "Unstandard CubeSat/PocketQube/TubeSat Deployers" from April 23, 2015.
A Radio Frequency Beacon Receiver For Detection Of Ionospheric Scintillation, Tim Neilsen, Don Thompson, Steve Higley, Todd Parris, Jake Gunther
A Radio Frequency Beacon Receiver For Detection Of Ionospheric Scintillation, Tim Neilsen, Don Thompson, Steve Higley, Todd Parris, Jake Gunther
Space Dynamics Laboratory Publications
Radio Frequency Beacon Receiver
- What is RFBR?
- A low-cost, ground-based beacon receiver
- Producing ionospheric parameters:
- Total Electron Content (TEC)
- Amplitude scintillation (S4)
- Phase scintillation (σφ)
- Using COTS RF hardware and Software Defined Radios (SDRs)
- Advanced algorithms and software
Flying The X-15 And Space Shuttle, Joe H. Engle
Flying The X-15 And Space Shuttle, Joe H. Engle
ERAU Prescott Aviation History Program
Hear what it was like for Joe H. Engle, USAF/ANG, Ret. to fly both the X-15 and the Space Shuttle. In 1965 Capt. Engle flew the X-15 to 280,600 feet, to become the youngest pilot to qualify as an astronaut and would go on to fly it 15 more times. Selected for NASA space missions, he flew the Space Shuttle “Enterprise” off the top of a modified 747 on glide flight tests. He commanded the orbital test flight of “Columbia” and became the first and only pilot to manually fly an aerospace vehicle from Mach 25 to landing. A remarkable …
Cdtx: Cool Drop Test Experiment, Robert J. Twiggs
Cdtx: Cool Drop Test Experiment, Robert J. Twiggs
Robert "Bob" Twiggs STEM Education Collection
A PowerPoint presentation created by Professor Bob Twiggs titled "CDTX: Cool Drop Test Experiment" from April 7, 2015.
High Powered Composite Payload Fairing Rocket For Deployable Robotics, Markus R. Murdy
High Powered Composite Payload Fairing Rocket For Deployable Robotics, Markus R. Murdy
Research Horizons Day Posters
No abstract provided.
Comparison Of Radiation Dosage For Human Piloted Mars Missions Using Chemical, Nuclear Thermal, And Fusion Propulsion Systems, Steven Doyle
Comparison Of Radiation Dosage For Human Piloted Mars Missions Using Chemical, Nuclear Thermal, And Fusion Propulsion Systems, Steven Doyle
Research Horizons Day Posters
No abstract provided.
Flow Induced Vibration On Piezoelectric Structures: Prediction, Experiment And Applications, Felix Ewere
Flow Induced Vibration On Piezoelectric Structures: Prediction, Experiment And Applications, Felix Ewere
Research Horizons Day Posters
No abstract provided.
Particulate Matter Emission Estimates From Agricultural Spring Tillage Operations Using Lidar And Inverse Modeling, Kori D. Moore, Michael D. Wojcik, Randal S. Martin, Christian C. Marchant, Derek S. Jones, William J. Bradford, Gail E. Bingham, Richard L. Pfeiffer, John H. Prueger, Jerry L. Hatfield
Particulate Matter Emission Estimates From Agricultural Spring Tillage Operations Using Lidar And Inverse Modeling, Kori D. Moore, Michael D. Wojcik, Randal S. Martin, Christian C. Marchant, Derek S. Jones, William J. Bradford, Gail E. Bingham, Richard L. Pfeiffer, John H. Prueger, Jerry L. Hatfield
Space Dynamics Laboratory Publications
Particulate matter (PM) emissions from a typical spring agricultural tillage sequence and a strip-till conservation tillage sequence in California’s San Joaquin Valley were estimated to calculate the emissions control efficiency (η) of the strip-till conservation management practice (CMP). Filter-based PM samplers, PM-calibrated optical particle counters (OPCs), and a PM-calibrated light detection and ranging (lidar) system were used to monitored upwind and downwind PM concentrations. Emission rates were estimated through inverse modeling coupled with the filter and OPC measurements and through applying a mass balance to the PM concentrations derived from lidar data. Sampling irregularities and errors prevented the estimation of …
Slip Length Crossover On A Graphene Surface, Zhi Liang, Pawel Keblinski
Slip Length Crossover On A Graphene Surface, Zhi Liang, Pawel Keblinski
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Using Equilibrium and Non-Equilibrium Molecular Dynamics Simulations, We Study the Flow of Argon Fluid above the Critical Temperature in a Planar Nanochannel Delimited by Graphene Walls. We Observe that, as a Function of Pressure, the Slip Length First Decreases Due to the Decreasing Mean Free Path of Gas Molecules, Reaches the Minimum Value When the Pressure is Close to the Critical Pressure, and Then Increases with Further Increase in Pressure. We Demonstrate that the Slip Length Increase at High Pressures is Due to the Fact that the Viscosity of Fluid Increases Much Faster with Pressure Than the Friction Coefficient between …
Delamination Of C/Pekk I-Beam Using Virtual Crack Closure Technique And Cohesive Zone Method, Greeshma Ramakrishna
Delamination Of C/Pekk I-Beam Using Virtual Crack Closure Technique And Cohesive Zone Method, Greeshma Ramakrishna
Open Access Theses
A damage study is conducted on a carbon epoxy/PEKK (poly-ether-ketone-ketone) thermoplastic composite I-Beam, with a pre crack of 100 mm modeled between the top flange and the filler (butt joint between filler and web). This project is in collaboration with Fokker Aerostructures, Netherlands and is part of the Thermoplastic Primary Aircraft Structure innovation program (TAPAS). The C/PEKK I-Beam is modeled after a section of the Gulfstream G650 aircraft's centre beam, which was previously a carbon fiber/epoxy hat-stiffened skin construction. The objective of the thesis is to identify if the crack propagates in the I-Beam within the load range that act …
An Experimental Study On The Effects Of Blade Row Interactions On Aerodynamic Loss Mechanisms In A Multistage Compressor, Natalie Rochelle Smith
An Experimental Study On The Effects Of Blade Row Interactions On Aerodynamic Loss Mechanisms In A Multistage Compressor, Natalie Rochelle Smith
Open Access Dissertations
While the gas turbine engine has existed for nearly 80 years, much of the complex aerodynamics which governs compressor performance is still not well understood. The unsteady flow field consists of periodic blade row interactions from the wakes and potential fields of each blade and vane. Vane clocking is the relative circumferential indexing of adjacent vane rows with the same vane count, and it is one method to change blade row interactions. Though the potential of performance benefits with vane clocking is known, the driving flow physics have yet to be identified. ^ This research examines the effects of blade …
The Panther: 2015 Aiaa Design Build Fly, Bryce Milnes, Chris Crawford
The Panther: 2015 Aiaa Design Build Fly, Bryce Milnes, Chris Crawford
Publications
The ERAU Prescott chapter of AIAA participated in the 2015 AIAA Design Build Fly competition at Raytheon Missile Systems in Tucson from April 10-12. A remote controlled aircraft meeting and exceeding all competition performance requirements was designed and fabricated by the 30+ students of the team. Additionally, a 60 page report was submitted detailing the project starting from initial considerations and advancing through flight test verification of aircraft capabilities. The success of this project was enabled by the E-Prize and SGA funding received to support our efforts throughout the year. The lessons learned regarding management and planning, engineering design approaches, …
Unmanned Aerial Vehicle (Uav) Propulsion Research: Conceptual Studies Of “Ultra-Compact Shaft-Less Jet Engines” For Next Generation Uavs, Tyler Eiguren, Trevor Douglas, Tre Buchanan
Unmanned Aerial Vehicle (Uav) Propulsion Research: Conceptual Studies Of “Ultra-Compact Shaft-Less Jet Engines” For Next Generation Uavs, Tyler Eiguren, Trevor Douglas, Tre Buchanan
Publications
Unmanned Aerial Vehicles are becoming more commonly used in today’s society, ranging anywhere from military applications to entertainment for enthusiasts and hobbyists. The complexity of current generation UAV’s propulsive devices, based upon a scaled turbine engine and separate gas & electrically powered rotating fan blades, require regular maintenance for every 24 hours of flight. This added cost coupled with necessary intricate machinery deters UAV designers from such engines, leaving a void in current production. Our research team believes that by combining a simplified alternative compression & combustion process with an electrically driven fan, we can develop an energy efficient, reliable, …
Comprehensively Simulating The Mixed-Mode Progressive Delamination In Composite Laminates, Zhenyuan Gao
Comprehensively Simulating The Mixed-Mode Progressive Delamination In Composite Laminates, Zhenyuan Gao
Open Access Theses
Delamination, or interlaminar debonding, is a commonly observed failure mechanism in composite laminates. It is of great significance to comprehensively simulate the mixed-mode progressive delamination in composite structures because by doing this, people can save a lot of effort in evaluating the safe load which a composite structure can endure.^ The objective of this thesis is to develop a numerical approach to simulating double-cantilever beam (DCB) and mixed-mode bending (MMB) tests and also of specifying/validating various cohesive models. A finite element framework, which consists of properly selecting time integration scheme (explicit dynamic), viscosity, load rate and mass scaling, is developed …