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Parasitic Drag Analysis Of A High Inertia Flywheel Rotating In An Enclosure, Chad C. Panther Jan 2008

Parasitic Drag Analysis Of A High Inertia Flywheel Rotating In An Enclosure, Chad C. Panther

Graduate Theses, Dissertations, and Problem Reports

There are currently millions of people throughout the world who live in isolated, rural communities without electricity. An ongoing effort has been initiated to provide reliable power to such communities. These efforts are being made to utilize renewable energy sources such as wind and solar power to solve this problem. Renewable energy sources can be both intermittent and unpredictable. Thus, an effective energy storage system is sought to store excess energy when available to disperse during times of scarcity.;The use of a high-inertia flywheel was proposed as a means of energy storage due to its simplicity, low cost, and reliability. …


Effect Of Circulation Control Blowing Slots On Stall Angles Of A 10:1 Elliptical Airfoil, Jonathan Kweder Jan 2008

Effect Of Circulation Control Blowing Slots On Stall Angles Of A 10:1 Elliptical Airfoil, Jonathan Kweder

Graduate Theses, Dissertations, and Problem Reports

Circulation control is a high-lift methodology that can be used on the wing of an aircraft. This technology has been in the research and development phase for over sixty years primarily for fixed wing aircraft when the early models were referred to as "blown flaps." Circulation control works by increasing the near surface velocity of the airflow over the leading edge and/or trailing edge of a specially designed aircraft wing using a series of blowing slots that eject high velocity jets of air. The wing has a rounded trailing edge, and ejects the air tangentially, through these slots inducing the …


Application Of Machine Vision In Uavs For Autonomous Target Tracking, Joshua Patrick Effland Jan 2008

Application Of Machine Vision In Uavs For Autonomous Target Tracking, Joshua Patrick Effland

Graduate Theses, Dissertations, and Problem Reports

This research presents experimental results for the application of Machine Vision (MV) techniques to address the problem of target detection and tracking. The main objective is the design of a prototype "UAV" surveillance environment to emulate real-life conditions. The model environment for this experiment consists of a target simulated by a small electric train system, located at "ground" level, and a MV camera mounted on a motion-based apparatus located directly above the model setup. This system is meant to be a non-flying mockup of an aerial robot retrofitted with a MV sensor. Therefore, the final design is a two degree-of-freedom …


Computational Analysis Of Pitch Stability For A Slotted Airfoil In Ground Effect, Meagan L. Hubbell Jan 2008

Computational Analysis Of Pitch Stability For A Slotted Airfoil In Ground Effect, Meagan L. Hubbell

Graduate Theses, Dissertations, and Problem Reports

Ground effect is a phenomenon which occurs when flow is displaced around a moving body in close proximity to the ground. This displacement is caused by compressed air that becomes trapped during motion between the body and the ground. The added upward thrust caused by ground effect can be used to generate and augment lift on a small aircraft. AirRay is a small single person, recreational downhill glider that operates within this ground effect. When launched from the top of a hill, it can glide to the base using ground effect for lift.;One of the amplified effects of operating close …


Control Of A Swept Wing Tailless Aircraft Through Wing Morphing, Richard W. Guiler Aug 2007

Control Of A Swept Wing Tailless Aircraft Through Wing Morphing, Richard W. Guiler

Graduate Theses, Dissertations, and Problem Reports

Inspired by flight in nature, work done by Lippisch, the Hortens, and Northrop offered insight to achieving the efficiency of bird flight with swept-wing tailless aircraft. Tailless designs must incorporate aerodynamic compromises for control, which have inhibited potential advantages. A morphing mechanism, capable of changing the twist of wing and that can also provide pitch, roll and yaw control for a tailless swept wing aircraft is the first step to a series of morphing techniques, which will lead to more fluid, bird-like flight. This research focuses on investigating the design of a morphing wing to improve the flight characteristics of …


Pressure Deflection Behavior Of Candidate Materials For A Morphing Wing, Christopher Griffin Aug 2007

Pressure Deflection Behavior Of Candidate Materials For A Morphing Wing, Christopher Griffin

Graduate Theses, Dissertations, and Problem Reports

The research presented in this thesis evaluates different materials that are candidates to be used as a flexible skin on a morphing wing. A morphing wing has come to be known as any wing that changes shape. Although there has been a great amount of research involved in designing morphing mechanisms, the information for applicable wing skin material has been limited. A morphing wing skin needs to be flexible enough to deflect and morph to a new shape given a suitable amount of force, yet strong enough to resist the aerodynamic forces encountered during flight. It also must remain elastic …


Numerical Investigation Of Wing Morphing Capabilities Applied To A Horten Type Swept Wing Geometry, Ashwin Vishwanathan May 2007

Numerical Investigation Of Wing Morphing Capabilities Applied To A Horten Type Swept Wing Geometry, Ashwin Vishwanathan

Graduate Theses, Dissertations, and Problem Reports

The inspiration for this work has been derived from the work done by Lippisch, the Hortens, Northrop and largely by the flight of birds in nature. Swept-wing tailless aircraft have been in vogue since World War-II and have now taken on a new role in stealth warfare primarily due to their low radar signatures. They also exhibit a highly efficient aerodynamic configuration with low parasitic drag. However, conventional tailless aircraft suffer from a lack of proper control mechanisms and have thus been forced to compromise their efficiency for better control. This work done at WVU aims to introduce a morphing …


Numerical Study Of Wingtip Shed Vorticity Reduction By Wing Boundary Layer Control, Jose Alejandro Posada May 2007

Numerical Study Of Wingtip Shed Vorticity Reduction By Wing Boundary Layer Control, Jose Alejandro Posada

Graduate Theses, Dissertations, and Problem Reports

Wingtip vortex reductions have been obtained by Boundary Layer Control application to an AR=1.5 rectangular wing using a NACA 0012 airfoil. If wingtip shed vorticity could be reduced significantly, then so would induced drag resulting in improved cruise fuel economy. Power savings would be even more impressive at low flight speed or in climb.;A two dimensional wing produces lift without wingtip vorticity. Its bound vorticity, Gamma, equals the contour integral of the boundary layer vorticity gamma or Gamma = ∮gamma · dl. Where the upper and lower boundary layers meet at the cusped TE, their local static pressure pu=pl then …


Computational Analysis Of Airfoils In Ground Effect For Use As A Design Tool, Justin L. Smith Jan 2007

Computational Analysis Of Airfoils In Ground Effect For Use As A Design Tool, Justin L. Smith

Graduate Theses, Dissertations, and Problem Reports

There has been interest shown in a recreational glider which operates primarily in the flight regime known as ground effect. Ground effect traditionally occurs when the airfoil is within a chords length of the ground. It is well known in the art that when the airfoil is present in ground effect the lift force is increased and the drag force is reduced on the lifting surfaces, in turn increasing the L/D ratio.;This recreational glider would have no internal power supply and only rely on the outside acting force. The considered force that would be used to propel this recreational glider …


Development Of A Numerical Model Of A Two-Dimensional Inertial Gas Separator, Henry Z. Graham Iv Dec 2006

Development Of A Numerical Model Of A Two-Dimensional Inertial Gas Separator, Henry Z. Graham Iv

Graduate Theses, Dissertations, and Problem Reports

The separation of gases is required for a variety of applications such as purification for industrial processes, natural gas production, isotope formation, etc. Gas separation is a costly expenditure for businesses, so new and improved methods are being continuously investigated. Separation techniques related to the method in this thesis are diffusion separators such as mechanical centrifuges, vortexes and the use of shock waves to cause the separation based on the molecular weight of the different gases. These methods and others are constantly being investigated and improved to increase their effectiveness.;The purpose of this thesis was to determine if the design …


Express Risk Assessment For The Dispersion Of Aerosols In An Urban Environment Using Probabilistic Implicit Tracking, Steven Lee Rowan Dec 2006

Express Risk Assessment For The Dispersion Of Aerosols In An Urban Environment Using Probabilistic Implicit Tracking, Steven Lee Rowan

Graduate Theses, Dissertations, and Problem Reports

The dispersion or transport of an airborne aerosol, whether the result of pollution or terrorist attack, is a topic of much interest to researchers and governmental officials in the United States. Due to this, there have been numerous efforts to develop accurate aerosol dispersion models utilizing computational fluid dynamics (CFD) and Lagrangian Particle Dynamics (LPD) in order to predict how an aerosol-suspended material will propagate in an urban environment. However, the complexity of these models require significant amounts of computational resources and are not practical for quickly modeling an actual event.;In this study, a stochastic simulation of Probabilistic Implicit Tracking …


Machine Vision Applications In Uavs For Autonomous Aerial Refueling And Runway Detection, Larry W. Rowe Ii Aug 2006

Machine Vision Applications In Uavs For Autonomous Aerial Refueling And Runway Detection, Larry W. Rowe Ii

Graduate Theses, Dissertations, and Problem Reports

This research focuses on the application of Machine Vision (MV) techniques and algorithms to the problems of Autonomous Aerial Refueling (AAR) and Runway Detection. In particular, real laboratory based hardware was used in a simulated environment to emulate real-life conditions for AAR. It was shown that the K-Means Clustering Algorithm solution to the Marker Detection problem could be executed at a frame rate of 30 Hz and it averaged a tracking error of less than one pixel while utilizing only 0.16% of the image. It was also shown that the solution to the Runway Detection problem could be executed at …


A Rotational Arm Connection Point Design For A C-130 Aircraft Standardized Sensor Platform, Kenneth A. Williams Aug 2006

A Rotational Arm Connection Point Design For A C-130 Aircraft Standardized Sensor Platform, Kenneth A. Williams

Graduate Theses, Dissertations, and Problem Reports

West Virginia University's Center for Industrial Research Applications (CIRA) was sponsored by the United States Army National Guard (USANG) and the Department of Defense (DOD) to design a standardized, articulating sensor platform for the C-130 Hercules military aircraft. This sensor platform was to be capable of in-flight deployment and capable of facilitating a diverse spectrum of sensor configurations in order to aid in surveillance and reconnaissance for counter narco-terrorism efforts. Two complete sensor pallet prototypes have been developed. The current platform configuration consists of four aluminum arms that are connected to a rotational shaft via a cylindrical hub. For the …


Design Of A Quick-Release Mechanism For A C-130 Aircraft Sensor Platform, Seth D. Lucey Aug 2006

Design Of A Quick-Release Mechanism For A C-130 Aircraft Sensor Platform, Seth D. Lucey

Graduate Theses, Dissertations, and Problem Reports

The development of a standardized sensor pallet system for a C-130 aircraft was conceived by the Center for Industrial Research Applications at West Virginia University to assist in counterdrug reconnaissance activities within the United States. The system has been completed and is now being optimized for various uses in addition to counterdrug reconnaissance. It is sought to have the sensor carriers/housings easily interchangeable so that they may be switched in the field by operators rather than in the hangar by technicians. The design parameters were established by the National Guard mission requirements and by the limitations of the C-130 aircraft. …


Effects Of The Electric Kelvin Force On Spray Cooling Performance, Shannon Lynnette Glaspell Aug 2006

Effects Of The Electric Kelvin Force On Spray Cooling Performance, Shannon Lynnette Glaspell

Graduate Theses, Dissertations, and Problem Reports

Spray cooling is an efficient thermal management technique that may possibly be improved by employing an electric Kelvin force to control the fluid motion and delay the onset of critical heat flux. In the present study, a spray cooling apparatus consisting of a spray chamber (housing a spray nozzle and electrically heated surface) and a flow generating base package has been built and tested for varying nozzle-to-heater distances and also varying electrode geometries for a range of spray conditions and electrode voltages. The two part goal was to first determine the qualitative sensitivity of the distance between the heated surface …


Characterization Of Self -Healing Composite Materials, Kevin John Ford Aug 2006

Characterization Of Self -Healing Composite Materials, Kevin John Ford

Graduate Theses, Dissertations, and Problem Reports

Damage occurs in almost every composite material in the form of microcracks that develop in the epoxy matrix that binds the fibers together. Researchers at the University of Illinois Urbana Champaign have recently developed a method to reverse the effects of, or heal, damage in the epoxy matrix. Their in-situ self-healing system uses embedded microcapsules and a catalyst that trigger a romp reaction in an effort to rebond the microcracks. Several models have been developed in an effort to predict how a composite laminate damages. One model in particular, the Continuous Damage Mechanics model, CDM that has been developed at …


Addressing Corner Detection Issues For Machine Vision Based Uav Aerial Refueling, Soujanya Vendra May 2006

Addressing Corner Detection Issues For Machine Vision Based Uav Aerial Refueling, Soujanya Vendra

Graduate Theses, Dissertations, and Problem Reports

The need for developing autonomous aerial refueling capabilities for an Unmanned Aerial Vehicle (UAV) has risen out of the growing importance of UAVs in military and non-military applications. The AAR capabilities would improve the range and the loiter time capabilities of UAVs. A number of AAR techniques have been proposed, based on GPS based measurements and Machine Vision based measurements. The GPS based measurements suffer from distorted data in the wake of the tanker. The MV based techniques proposed the use of optical markers which---when detected---were used to determine relative orientation and position of the tanker and the UAV. The …


Design And Simulation Of Advanced Fault Tolerant Flight Control Schemes, Srikanth Gururajan Jan 2006

Design And Simulation Of Advanced Fault Tolerant Flight Control Schemes, Srikanth Gururajan

Graduate Theses, Dissertations, and Problem Reports

This research effort describes the design and simulation of a distributed Neural Network (NN) based fault tolerant flight control scheme and the interface of the scheme within a simulation/visualization environment. The goal of the fault tolerant flight control scheme is to recover an aircraft from failures to its sensors or actuators. A commercially available simulation package, Aviator Visual Design Simulator (AVDS), was used for the purpose of simulation and visualization of the aircraft dynamics and the performance of the control schemes.;For the purpose of the sensor failure detection, identification and accommodation (SFDIA) task, it is assumed that the pitch, roll …


The Design Of A Rotor Blade Test Facility, Jason W. Gill Aug 2005

The Design Of A Rotor Blade Test Facility, Jason W. Gill

Graduate Theses, Dissertations, and Problem Reports

The Mechanical and Aerospace Engineering Department has developed a need for test facilities related to rotorcraft, specifically facilities capable of testing scaled rotorcraft models and experimental propellers and rotors. A design was completed to fill these needs.;The design included several factors; aerodynamic conditions during operation, flexibility of application, ease and cost of construction, and safety. The aerodynamic conditions involved in the testing of rotors or propellers in static conditions were investigated. Other testing involving downwash impingement on wings was considered and incorporated into the design.;In addition, the design of the power transmission components was completed. This included the power requirements …


Influence Of A Thermal Denuder On Diesel Exhaust Particle Size Distributions, Bobby John Aug 2005

Influence Of A Thermal Denuder On Diesel Exhaust Particle Size Distributions, Bobby John

Graduate Theses, Dissertations, and Problem Reports

Particle size distributions in diesel exhaust were studied using a thermal desorption technique to determine the volatile and non-volatile fractions. A thermal denuder was designed and characterized for optimal operating parameters and its influence on the exhaust chemistries studied using diesel engine exhaust. The study was conducted on a 1992 DDC Series 60 engine mounted on a heavy-duty direct current dynamometer and exercised over steady state and transient cycles. The particle size distributions were recorded upstream and downstream of the denuder maintained at different temperatures to determine the behavior of the volatile fraction. The volatilization technique was also applied to …


Methods For Creating A Multi-Axis Polarizer For Visible Light Attenuation By Linear Translation, Peter L. Donatelli Aug 2005

Methods For Creating A Multi-Axis Polarizer For Visible Light Attenuation By Linear Translation, Peter L. Donatelli

Graduate Theses, Dissertations, and Problem Reports

A few solutions exist that describe how a Linear Translation Multi-Axis (LTMA) polarizer can be made. It is the purpose here to describe some of these solutions and determine if these solutions are plausible. A positive result will be the creation of a LTMA polarizer in a continuous sheet.;As there are various ways to make a LTMA polarizer, there are also many materials used to make polarizers. Some of the types of polarizers that will be discussed consist of: a crystalline based dichroic polarizer, a molecular iodine polarizer, birefringent polarizers, metallic polarizers and light reactive dye polarizers.;What has resulted from …


Investigation Of Relative Humidity And Induced-Vortex Effects On Aircraft Icing, Egemen O. Ogretim May 2005

Investigation Of Relative Humidity And Induced-Vortex Effects On Aircraft Icing, Egemen O. Ogretim

Graduate Theses, Dissertations, and Problem Reports

Aircraft icing is an area of research that has drawn attention since the early times of powered flight at high altitudes. Since World War II, aircraft icing research has gained a great deal of momentum, and several branches of research have developed as a result. These branches include the experimental, analytical and computational methods. With the advent of high-speed computers, the computational methods are becoming the leading icing research area due to their low cost requirements. However, a significant hindrance is the lack of a complete understanding of the icing phenomena, which leads to discrepancies between the predictions and the …


Design, Construction And Initial Testing Of Experimental Test Package For Convective Spray Cooling In Terrestrial Gravity Conditions, Charles Andy Hunnell May 2005

Design, Construction And Initial Testing Of Experimental Test Package For Convective Spray Cooling In Terrestrial Gravity Conditions, Charles Andy Hunnell

Graduate Theses, Dissertations, and Problem Reports

The design and construction of an apparatus for spray cooling tests was completed to better understand the effects of spray cooling with different geometries at varied flow rates and different spray orientations. Three different geometries were studied at four different spray volumetric flow rates varying from 9.3 GPH to 4.6 GPH. At each spray flow rate the heat flux of the small heated pedestal located in the spray chamber was increased from 5 W/cm2 to 32.24 W/cm2. During these tests the spray orientation was changed from a vertical downward spray to a horizontal spray. The convective heat transfer coefficient and …


Electromagnetic Nondestructive Inspection Of Aircraft Structures By Using A Magnetic Flux Leakage Method, Iyad Mahmood Ali Muslih May 2005

Electromagnetic Nondestructive Inspection Of Aircraft Structures By Using A Magnetic Flux Leakage Method, Iyad Mahmood Ali Muslih

Graduate Theses, Dissertations, and Problem Reports

Aging of aircraft structures is mostly associated with fatigue cracking, de-bonding and corrosion. Detection and characterization of the structural defects at the initiation stages makes it a great challenge for any inspection technology. This study proposes a new solution for the nondestructive evaluation problem by using a magnetic flux method for non-ferromagnetic materials and provides a new neural network tool that predicts crack profiles in three dimensions by solving the inverse problem, where available neural networks can solve it in two dimensions only.;The discontinuity resulting from a crack produces disturbance to the distribution of electrical current density in the structure …


The Effect Of Adding Multiple Triangular Vortex Generators On The Leading Edge Of A Wing, Francisco Adolfo Pino Romainville Jan 2005

The Effect Of Adding Multiple Triangular Vortex Generators On The Leading Edge Of A Wing, Francisco Adolfo Pino Romainville

Graduate Theses, Dissertations, and Problem Reports

The goal of this research was to investigate preliminary test data obtained by Professor Robert E. Bond at the University of Tennessee in the year 2001. Dr. Bond added triangular horizontal flat plates (vortex generators) to the leading edge of a wing, to delay flow separation at high angles of attack. The present approach was both experimental and computational. The experimental method was used to determine, with the aid of smoke, the angle of attack at which the wing stalled. For this qualitative method a wing (airfoil NACA 0015) was used. It had a 32 inch span and attached to …


Comparison Of Numerical Simulation To Existing Experimental Data Involving Downwash Wake Reduction For The V-22 Osprey, Brian O'Hara Jan 2005

Comparison Of Numerical Simulation To Existing Experimental Data Involving Downwash Wake Reduction For The V-22 Osprey, Brian O'Hara

Graduate Theses, Dissertations, and Problem Reports

It is of interest to develop numerical techniques to simulate the implementation of blowing slots on a V-22 Osprey airfoil in order to alleviate downwash. In order to develop these techniques, two separate experiments were simulated and the numerical results were compared with the experimental data. The first experiment used in comparison was performed by Fort F. Felker at the NASA's AMES Research Center in 1990. The second experiment was done by Chad Riba and Gerald M. Angle at West Virginia University in 2003.;The commercially available RNG k-e turbulence model with enhanced wall treatment found in Fluent 6.1 was used …


Design And Flight Testing Actuator Failure Accommodation Controllers On Wvu Yf-22 Research Uavs, Yu Gu Dec 2004

Design And Flight Testing Actuator Failure Accommodation Controllers On Wvu Yf-22 Research Uavs, Yu Gu

Graduate Theses, Dissertations, and Problem Reports

This dissertation describes the design, development, and flight testing of a Neural Network (NN) based Fault Tolerant Flight Control System (FTFCS) with the ability to accommodate for actuator failures. The goal of this research was to demonstrate the ability of a specific set of control laws to maintain aircraft handling qualities in the presence of failures in the actuator channels. In this study, two-failure scenarios have been investigated: aileron failure (locking of the right aileron at a trim position) and elevator failure (locking of the right elevator at a trim position). A fleet of WVU YF-22 research aircraft test-beds were …


Dynamic Modal Analysis And Optimization Of C-130 Project Oculus' Mechanical Arm/Pod Sensor Deployment System Using The Finite Element Method, Adam C. Naternicola Aug 2004

Dynamic Modal Analysis And Optimization Of C-130 Project Oculus' Mechanical Arm/Pod Sensor Deployment System Using The Finite Element Method, Adam C. Naternicola

Graduate Theses, Dissertations, and Problem Reports

The Department of Defense (DoD) and the United States Army National Guard (USARNG) have sponsored West Virginia University's Center for Industrial Research Applications (CIRA) to design, fabricate, test and optimize an articulating, mechanical arm/pod system. The mechanical arm/pod system will be designed to accommodate a 500-pound sensor payload deployable in flight from a C-130 Hercules military aircraft used for counter narco-terrorism efforts. During the overall deployment (translation and rotation) of the mechanical arm/pod system and in the final resting position for optimal operating conditions for the data acquisition sensors (DAS), the mechanical structure will be subjected to a variety of …


Finite Element Modeling Of Crack Detection In Aircraft Structures Using Electrical Current, Ramkumar Kumar Geetha Aug 2004

Finite Element Modeling Of Crack Detection In Aircraft Structures Using Electrical Current, Ramkumar Kumar Geetha

Graduate Theses, Dissertations, and Problem Reports

Various non-destructive test methods have been developed for the detection of cracks in metallic structures. Electromagnetic non-destructive testing (NDT) is one of the widely used non-destructive methods used for the detection and characterization of cracks. Utilizing the principle of electromagnetic induction, this technique is used in the areas of nuclear, aerospace, power, transport, petroleum and other industries to inspect defects in metallic sheets, plates and tubes that have good electrical conductivity.;Aircraft structures and wings are made of aluminum sheets riveted together. Cracks are often found emanating from the edge of the rivet holes which are covered by the rivets and …


Control System Design For A C-130 Ro-Ro Sensor Deployment Platform, Robert Paul Hayes Aug 2004

Control System Design For A C-130 Ro-Ro Sensor Deployment Platform, Robert Paul Hayes

Graduate Theses, Dissertations, and Problem Reports

A WVU team of engineers designed and built a palletized system that will be used to deploy surveillance sensors from a C-130 cargo airplane. There will be two pallets, one that will house the Operator Station and one that will carry a mechanical arm with a Sensor Pod, where the sensors will reside. This pallet will be placed on the C-130 rear door, which will be opened while in flight. The mechanical arm is designed to rotate the Sensor Pod underneath the door so the sensors can observe the ground.;Computer/Electrical engineers were asked to design the control circuit for the …