| Wind Tunnel Analysis And Flight Test of A Wing Fence On A T-38 |
26-Mar-2009 |
267 pages |
| Authors:
Michael D Williams; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH DEPT OF AERONAUTICS AND ASTRONAUTICS
|
 | A low-speed wind tunnel study and flight tests were performed to examine the effects of a wing fence on the T-38A. Wind tunnel results were based upon force and moment data collected with a six-component balance and flow visualization at Reynolds numbers up to 0.3 x 10(exp 6), based on mean aerodynamic chord. The model did not include the last 7.79 feet of the aircraft, and the engine and exhaust ... |
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| Evaluation of the Haltere as a Biologically-Inspired Inertial Rate Sensor |
Mar-2009 |
16 pages |
| Authors:
R A Thompson; M F Wehling; J E Evers; W E Dixon; AIR FORCE RESEARCH LAB EGLIN AFB FL MUNITIONS DIRECTORATE
|
| Since as early as the 1940's, specialized structures on dipteran insects have been recognized as necessary for inertial measurement associated with basic flight stability. These structures, called halteres, have been suggested to act as vibrating structure gyroscopes, measuring strains proportional to Coriolis accelerations. As a miniature, robust means for stabilizing flight, this biological inertial measurement system is not only of interest to biologists, but also to designers of biomimetic robotic ... |
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| Developing a Framework for Control of Agile Aircraft Platforms in Autonomous Hover |
Mar-2009 |
75 pages |
| Authors:
Kyle J Krogh; WASHINGTON UNIV SEATTLE DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| This thesis extends previous work on autonomous agile aircraft to develop a framework for control in both linear and non-linear flight profiles. Two dynamical systems are considered, a scale YAK-54 aerobatic remote control aircraft and the Flexrotor concept developed by Aerovel. Both models are capable of hover and level flight, requiring complex control transitions between the flight regimes. Linear controllers are developed for both models in a hover configuration. Open-loop ... |
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| Enabling Technologies for Nano Air Vehicles |
10-Feb-2009 |
86 pages |
| Authors:
Jamey D Jacob; OKLAHOMA STATE UNIV STILLWATER
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| This project investigated several areas with the aim of improving performance and operational use of nano air vehicles (NAVs) by understanding fundamental operating principles and developing key technologies. The project developed plasma actuators for thrust and maneuvering control and examined flapping flight through the development of a high speed videogrammetry system and a gust/shear tunnel to replicate flow fields seen as the NAY scale. In the first portion of the ... |
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| Enabling Technologies for Nano Air Vehicles |
10-Feb-2009 |
85 pages |
| Authors:
Jamey D Jacob; OKLAHOMA STATE UNIV STILLWATER
|
| This project investigated several areas with the aim of improving performance and operational use of nano air vehicles (NAVs) by understanding fundamental operating principles and developing key technologies. The project developed plasma actuators for thrust and maneuvering control and examined flapping flight through the development of a high speed videogrammetry system and a gust/shear tunnel to replicate flow fields seen as the NAV scale. In the first portion of the ... |
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| Stochastic Analysis and Control of Transonic Helicopter Aerodynamics and Supersonic Projectiles |
02-Feb-2009 |
6 pages |
| Authors:
Sivaguru S Sritharan; WYOMING UNIV LARAMIE
|
| The main goal of this project is to develop a systematic mathematical theory for the robust real time feedback control and stochastic analysis of unsteady transonic aerodynamics of helicopter rotor blades, supersonic ballistic projectiles and propagation of blast waves in the presence of adverse external disturbances. The proposed work builds upon similar scientific advances by the principal investigator in the context of incompressible fluid dynamics, magneto-hydrodynamics and combustion models during ... |
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| Autonomous Micro Air Vehicles with Hovering Capabilities |
Feb-2009 |
115 pages |
| Authors:
Sergey Shkarayev; ARIZONA UNIV TUCSON DEPT OF AEROSPACE AND MECHANICAL ENGINEERING
|
| In this project was investigated novel concepts of micro aerial vehicles (MAVs) with vertical takeoff and landing capabilities. Two fixed-wing MAV configurations were tested in a wind tunnel. These concepts were a tilt-wing concept MAV by two non-coaxial counter-rotating propellers and a tilt-body concept based on coaxial motors and counter-rotating propellers. Values of thrust, torque, power, and efficiency were measured for these concepts. The development of an automatic control system ... |
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| Nonlinear Structures Optimization for Flexible Flapping Wing MAVs |
Feb-2009 |
19 pages |
| Authors:
Robert L Jr; Walker; Craig E Svanberg; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AIR VEHICLES DIRECTORATE
|
| This report documents the culmination of in-house and AFIT collaboration in the area of nonlinear structures optimization for flexible flapping wing MAVs. The work was divided into four different tasks, including: Preliminary design of flapping wing device, Couple Abaqus with aerodynamic model, Comparison of experimental and computational results, and Evaluate CSIRF progress for transition to FY09 6.2 program. Technology developed in this task is being transitioned in the VAES program ... |
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| Tuning of the Preferred Optic Flow Axes of Locust and Blowfly Visual Interneurons to Their Preferred Modes of Flight Behaviour |
17-Dec-2008 |
6 pages |
| Authors:
Holger G Krapp; R J Bomphrey; S B Laughlin; G K Taylor; D G Wuestenberg; IMPERIAL COLL LONDON (UNITED KINGDOM) DEPT OF BIOENGINEERING
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| This report results from a contract tasking Imperial College London as follows: The grantee will investigate the sensory mechanisms of gaze stabilization and flight control on insects (flies and locusts). The study aims at understanding the underlying biological design principles. The research includes techniques ranging from neurophysiology and neuroanatomy to quantitative behavioral observations complemented by analytical and numerical modeling. Focus is on multi-sensory integration (visual and mechanosensory information), biophysical mechanisms ... |
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| A Fundamental Study in Nonlinear Aeroelastic Phenomena in Flapping Wing Micro Air Vehicles |
30-Nov-2008 |
9 pages |
| Authors:
Peretz P Friedmann; Wei Shyy; MICHIGAN UNIV ANN ARBOR DEPT OF AEROSPACE ENGINEERING
|
| This report describes the development of an aeroelastic model capable of representing in an approximate manner the fundamental nonlinear aeroelastic behavior of flapping wing micro air vehicles in hover. The approximate nature of the model is due to an approximate nonlinear two dimensional unsteady aerodynamic model based on a vortex approach that accounts for the leading edge vortex shed from the leading edge of the flapping wing. This approximate aerodynamic ... |
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| Flight Test Success through Effective Mission Assurance Strategy |
19-Nov-2008 |
13 pages |
| Authors:
Larry Easterwood; MISSILE DEFENSE AGENCY WASHINGTON DC
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| An effective Mission Assurance Strategy must: 1) Influence program execution and behavior in order to achieve mission success 2) Require unfettered access to the highest organizational leadership, programs and supply chain 3) Be empowered and supported by the highest level of organizational authority 4) Hold program offices and contractor's accountable for practices impacting mission success. |
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| Unique Stealth Unmanned Aerial Vehicle (UAV) Houck Aircraft Design Program. Volume 1: Program Overview |
Nov-2008 |
79 pages |
| Authors:
Aaron Altman; DAYTON UNIV OH
|
| This report will summarize the work performed to better understand the aerodynamics and potential benefits to using a biplane configuration with endplates in the aerodynamic regime experienced by a small unmanned aerial vehicle (UAV). Topics investigated include aerodynamic lift and drag, as well as a vehicle sizing study. Wind tunnel testing resulted in the conclusion that there is a substantial difference between positive and negative stagger; it also exposed a ... |
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| Evaporation Rates of Chemical Warfare Agents Using 5-CM Wind Tunnels I. CASARM Sulfur Mustard (HD) from Glass |
Oct-2008 |
187 pages |
| Authors:
John Pence; Aaron Flowers; Chris V Giannaras; Erin Maloney; Joseph P Myers; Robert G Nickol; Kenneth B Sumpter; Carol A Brevett; H D Durst; Bruce E King; EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD
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| The evaporation of sulfur mustard (HD) from glass was studied as a function of temperature, drop size, and airflow rate. The evaporation rate was measured by collecting the HD vapor using thermal desorption tubes that were connected to the wind tunnel. The evaporation rate increased with higher temperature, drop size, and wind speed. Five different wind tunnels were used, and it was possible to fit all of the data generated ... |
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| Nonlinear Dynamic Response Optimization Using the Equivalent Static Loads for a Joined-Wing |
01-Sep-2008 |
49 pages |
| Authors:
Gyung-Jin Park; HANYANG UNIV GYEONGGI-DO (SOUTH KOREA) DEPT OF MECHANICAL ENGINEERING
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| The joined-wing airplane proposed by Wolkovich in 1986 is defined as an airplane that incorporates tandem wings arranged to form diamond shapes in both top and front views. The joined-wing can lead to increased aerodynamic performances as well as reduction of the structural weight. However, the joined-wing has high geometric nonlinearity under the gust load. The gust load acts as a dynamic load. In previous researches, linear dynamic response optimization ... |
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| Morphing Aircraft Structures: Research in AFRL/RB |
01-Sep-2008 |
35 pages |
| Authors:
Brian Sanders; Shiv Joshi; Jayanth Kudva; Geoffrey J Frank; Franklin E Eastep; Bryan Cannon; Matthew P Snyder; Jason C Bowman; Gregory W Reich; Terrence Weisshaar; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AIR VEHICLES DIRECTORATE
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| This report reviews research in several different areas related to morphing aircraft structures undertaken in AFRL/RBSA. The first is an aeroelastic analysis of a folding-wing vehicle to determine the flutter boundaries of the wing at different fold angles. The second is the development of a simulation tool to study both the flight stability of a morphing vehicle during the morphing process, and the kinematic stability of the morphing mechanism subject ... |
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| Identification of Human Factors Concerns in Joint Strike Fighter and Training Recommendations |
01-Sep-2008 |
161 pages |
| Authors:
Arif B Bitik; Buelent Kueluenk; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Military aviation is the frontier of implementing leading edge technology. The major objectives of advanced technology aircraft are to increase pilot safety and mission efficiency; the Joint Strike Fighter, the most modern fighter aircraft under development, has many technological innovations for just this purpose. A common fact is that technology develops and is used faster than it can be researched thoroughly. This thesis seeks to identify and mitigate potential human ... |
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| Navier-Stokes Predictions of Dynamic Stability Derivatives: Evaluation of Steady-State Methods |
Sep-2008 |
44 pages |
| Authors:
Paul Weinacht; James DeSpirito; Sidra I Silton; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
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| The prediction of the dynamic stability derivatives-roll-damping, Magnus, and pitch-damping moments-were evaluated for three spin-stabilized projectiles using steady-state computational fluid dynamic (CFD) calculations. Roll-damping CFD predictions were found to be very good across the Mach number range investigated. Magnus moment predictions were very good in the supersonic flight regime; however, the accuracy varied in the subsonic and transonic flight regime. The best Magnus moment prediction in the subsonic flight regime ... |
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| Initial Characterization of Three-Dimensional Flow Separation in a Compressor Stator (Preprint) |
01-Jun-2008 |
16 pages |
| Authors:
S T Bailie; Grant A Hile; Steven L Puterbaugh; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
|
| A research program is underway seeking to effect a net decrease in aerodynamic loss of a moderately loaded axial compressor stator passage across varying operating conditions. Three dimensional boundary layer separation, typical at the suction surface corners, can differ greatly from classical two dimensional separation, and is the dominant loss and blockage generating feature in the diffusing flowfield of compressor stators. The initial research phase is presently described, wherein a ... |
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| Extending CFD Modeling to Near-Continuum Flows Using Enhanced Thermophysical Modeling |
Mar-2008 |
118 pages |
| Authors:
Abram E Claycomb; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH DEPT OF AERONAUTICS AND ASTRONAUTICS
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| The constitutive relations found in traditional Navier-Stokes-based computational fluid dynamics solvers are known to be limited in altitude. The presence of nonequilibrium phenomena beyond what these methods are able to predict becomes more prevalent at higher altitudes, or increasing Knudsen number. The bulk viscosity, normally assumed to be zero in most computational fluid dynamics applications, is examined as a means of increasing the range of applicability of computational fluid dynamics. ... |
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| Numerical Study of Unsteady Low-Reynolds Number Wing Performance |
29-Feb-2008 |
41 pages |
| Authors:
Ashok Gopalarothnam; Gregory Z McGowan; NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF MECHANICAL AND AEROSPACE ENGINEERING
|
| Unsteady motions of airfoils at low Reynolds numbers were studied computationally using low-order vortex lattice methods and using two high-order methods: a Reynolds Averaged Navier-Stokes code and an Immersed Boundary method. Results from the low-order methods compared well with experimental and computational results in the literature for small reduced amplitudes and frequencies. The high-order methods were compared with experiments on high intensity pitch and plunging motions at Reynolds numbers of ... |
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| The 2009 Version of the Aeroprediction Code: The AP09 |
JAN 2008 |
135 pages |
| Authors:
Frank G. Moore; Linda Y. Moore; AEROPREDICTION INC KING GEORGE VA
|
| The AP05 code was evaluated when applied to configurations with boattails. Results of the evaluation indicated the AP05 predictions for normal force, center of pressure, pitch and roll damping moments needed improvement. As a result new and improved methods were developed and incorporated into the AP05 to be released as the AP09. Improvements include body alone lift characteristics for Mach numbers less than 2, low angle of attack improvements for ... |
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| The Temporal Resolution of Flight Attitude Control in Dragonflies and Locusts: Lessons for the Design of Flapping-Wing MAVs |
04 DEC 2007 |
16 pages |
| Authors:
Gert Stange; Fabian Schmeling; Richard Berry; Gerlinde Lenz; AUSTRALIAN NATIONAL UNIV CANBERRA (AUSTRALIA) RESEARCH SCHOOL OF BIOLOGICAL SCIENCES
|
| In order to identify stability constraints in flapping-winged MAVs, within the context of longitudinal stabilization of flight attitude, the question is examined whether insects are capable of controlling flight attitude at the temporal resolution of a single wing beat. It is found that the phenomenon of phase locking between a periodic light flash and the wingbeat of insects is suitable for the examination of the time resolution with which vision ... |
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| Topology Synthesis of Distributed Actuation Systems for Morphing Wing Structures (Postprint) |
DEC 2007 |
12 pages |
| Authors:
Daisaku Inoyam; Brian P. Sanders; James J. Joo; DAYTON UNIV OH DEPT OF MECHANICAL AND AEROSPACE ENGINEERING
|
| This paper presents a novel topology optimization methodology for a synthesis of distributed actuation systems with specific applications to morphing air vehicle structures. The main emphasis is placed on the topology optimization problem formulation and the development of computational modeling concepts. The analysis model is developed to meet several important criteria: It must allow a large rigid-body displacement, as well as a variation in planform area, with minimum strain on ... |
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| Magneto-Fluid Dynamics Calculations for Aerodynamics |
20 NOV 2007 |
35 pages |
| Authors:
Robert W. MacCormack; STANFORD UNIV CA DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| Magneto-Hydro-Dynamics (MHD) or more generally Magneto-Fluid-Dynamics (MFD) offers a potential breakthrough in both hypersonic vehicle design and propulsion. Reductions in both drag and heat transfer and flow control using magnetic fields can be important for enabling a hypersonic vehicle to pass more efficiently and safely through the atmosphere. Magnetic and electric fields placed within the propulsion system may enable the extraction of electrical energy from the ionized flow entering the ... |
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| Experimental Elastic Deformation Characterization of a Flapping-Wing MAV Using Visual Image Correlation |
NOV 2007 |
18 pages |
| Authors:
Kelly Stewart; Roberto Albertani; AIR FORCE RESEARCH LAB EGLIN AFB FL MUNITIONS DIRECTORATE
|
| This presentation will detail AFRL/RW's collaboration with the University of Florida to derive a method for estimating elastic deformation in flexible, flapping wings. By knowing the elastic deformation that occurs, researchers can better understand the mechanics and aerodynamic effects behind flexible, flapping wings and apply that knowledge to various design aspects of micro air vehicles (MAV's) such as wing structure, guidance and control, etc. |
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| A CFD Study of the Aerodynamics of a 6x6x8 Foot Cargo Container Suspended Beneath a Helicopter. Part 1: Aerodynamics of the Stationary Container |
OCT 2007 |
78 pages |
| Authors:
Johannes N. Theron; Earl P. Duque; Luigi Cicolani; NORTHERN ARIZONA UNIV FLAGSTAFF
|
| This report is the first of several on a study of the unsteady aerodynamics of the CONEX cargo container This work is in support of an effort to develop a model of the CONEX unsteady aerodynamics for use in simulations of helicopter-slung-load dynamics It is known from the literature on cargo container aerodynamics that instability is caused by unsteady flow effects such as vortex shedding and flow structure lags and ... |
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| Multi-Objective and Multidisciplinary Design Optimisation (MDO) of UAV Systems using Hierarchical Asynchronous Parallel Evolutionary Algorithms |
17 SEP 2007 |
100 pages |
| Authors:
L. Damp; L. F. Gonzalez; K. Srinivas; SYDNEY UNIV (AUSTRALIA) SCHOOL OF AEROSPACE MECHANICAL AND MECHATRONIC ENGINEERING
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| Project report from basic science initiative to use Hierarchical Asynchronous Parallel Evolutionary Algorithms for MDO of a UAV system using high fidelity analysis tools. Two production UAV wings were examined for aerodynamic and structural properties. Optimization was performed over 48 design variables. |
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| Coupled CFD/GN&C Modeling for a Smart Material Canard Actuator |
SEP 2007 |
30 pages |
| Authors:
Paul Weinacht; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| The performance of a smart material canard actuator has been investigated using coupled computational fluid dynamics, guidance navigation and control, and structural models. The predictions show that the open-loop response of the smart material actuator does not produce the commanded deflection due to the interaction of the externally applied aerodynamic hinge moment with the flexible actuator structure. A closed-loop feedback control law with integral control is applied in order for ... |
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| Comparative Study of Aerodynamic Interference During AFT Dispense of Munitions |
SEP 2007 |
173 pages |
| Authors:
Matthew G. Burkinshaw; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| Based on forthcoming USAF needs, an investigation was launched to further the understanding of aft dispense of munitions in a high-speed environment. A computational fluid dynamics (CFD) study was performed followed by a wind tunnel experiment. The study consisted of a strut-mounted cone simulating a parent vehicle and a sting mounted cone-cylinder store situated directly behind the cone. The CFD modeled the test objects inside a supersonic wind tunnel in ... |
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| Computational Methods for Feedback Controllers for Aerodynamics Flow Applications |
15 AUG 2007 |
92 pages |
| Authors:
Stefan G. Siegel; Juergen J. Seidel; Thomas E. McLaughlin; Kelly Cohen; Selin Aradag; James R. Forsythe; William Z. Strang; COBALT SOLUTIONS LLC SPRINGFIELD OH
|
| This report covers the final results of the STTR: "Computational Methods for Feedback Controllers for Aerodynamics Flow Applications." It is intended to be a comprehensive summary of the project. The goal of the project was to provide a robust, easy to use computational tool for developing feedback controllers for aerodynamic flow applications - i.e. a tool to develop closed loop flow control methods. The two major partners of the STTR ... |
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| Design of the Air Force Research Laboratory Micro Aerial Vehicle Research Configuration |
AUG 2007 |
14 pages |
| Authors:
Kelly Stewart; Jeffrey Wagener; Gregg Abate; Max Salichon; AIR FORCE RESEARCH LAB EGLIN AFB FL MUNITIONS DIRECTORATE
|
| The Air Force Research Laboratory Munitions Directorate (AFRL/MN) is presently involved in many aspects of micro aerial vehicle (MAV) research. Among these are: advanced modeling and simulation models for MAVs, aero-structural interaction, advanced guidance techniques, hardware-in-the-loop simulations, and vehicle integration. In order to optimize collaboration within AFRL and also with outside research organizations, it was decided that a common MAV configuration be designed that would serve as a reference for ... |
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| Unsteady Low-Reynolds Number Aerodynamics for Micro Air Vehicles (MAVs) |
AUG 2007 |
9 pages |
| Authors:
Michael V. Ol; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AIR VEHICLES DIRECTORATE
|
| This report documents recent progress in in-house research in the AFRL Air Vehicles Directorate on unsteady aerodynamics at low Reynolds number. The application is the aerodynamics and flight dynamics of agile Micro Air Vehicles, to include flapping-wings. Experiments included quantitative and qualitative flowfield velocimetry on the Selig SD7003 airfoil, undergoing a range of harmonic and ramp motions in two degrees of freedom - that is, pitch and plunge. Relevant classical ... |
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| Theoretical Analysis of Control Mechanisms for Boundary-Layer Separation on Rotorcraft Blades |
01 JUN 2007 |
69 pages |
| Authors:
Philip A. Blythe; LEHIGH UNIV BETHLEHEM PA
|
| High maneuverability is one of the major goals in rotorcraft design. In practice, this goal is limited by unsteady (dynamic) stall near blade leading edges. Studies of three-dimensional boundary layer separation on a rotating blade are made. For hovering flight, the blade twist and downwash are included in the effective angle of attack. For forward flight, high angles of attack are used to simulate the most severe situation at the ... |
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| Exploring Naval Tactics with UAVs in an Island Complex Using Agent-Based Simulation |
JUN 2007 |
87 pages |
| Authors:
Vasileios Lalis; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The benefits of Unmanned Aerial Vehicles (UAV) at sea are undisputed. The amount and speed of the incoming information from a UAV, combined with its maneuverability and time-on-task capability, are assets to any navy. For the Greek Navy, the main local operation area is the Aegean and Ionian Sea. As Greece lies between three continents (Europe, Asia, Africa), there is a great deal of sea traffic and potential illegal activities, ... |
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| A Limited Evaluation of Full Scale Control Surface Deflection Drag (Have FUN) |
JUN 2007 |
75 pages |
| Authors:
R. B. Reinhardt; Sean A. Celi; Jeffrey T. Geraghty; James W. Stahl; Victor J. Glover; Geoffrey G. Bowman; AIR FORCE FLIGHT TEST CENTER EDWARDS AFB CA
|
| The Have FUN (FUll Scale Numbers) Test Management Project was conducted at the request of the USAF TPS as an investigation into the drag caused by control surface deflection during dynamic soaring techniques. Forty-three test sorties were performed from 6-23 March 2007 under Job Order Number (JON) M07C0200. The six member Have FUN test team from TPS Class 06B performed the testing at the North Base facilities of Edwards AFB. ... |
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| Pulsed Injection Flow Control for Throttling in Supersonic Nozzles - A Computational Fluid Dynamics Based Performance Correlation (Preprint) |
14 MAY 2007 |
16 pages |
| Authors:
Neal D. Domel; Dan Baruzzini; Daniel N. Miller; LOCKHEED MARTIN AERONAUTICS CO FORT WORTH TX
|
| A vehicle propelled by an engine with a variable geometry nozzle allows the nozzle expansion ratio to vary with altitude and flight condition, thereby optimizing vehicle performance. Rockets are examples of vehicles with high nozzle pressure ratios (NPRs), which operate over a large altitude range. Active flow control offers a method of reducing the effective aerodynamic throat of a rocket nozzle in a geometrically fixed structure. Throttling the mass flow ... |
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| Wind Tunnel and Water Channel Investigations for Improving MAV Aerodynamic Performance |
14 MAY 2007 |
11 pages |
| Authors:
Geoffrey Spedding; Frederick Browand; John McArthur; CALIFORNIA UNIV LOS ANGELES
|
| Extensive investigations of the role of sweep in generating and/or stabilizing a leading edge vortex (LEV) in low Reynolds number (Re = 10 000) aerodynamics were made by tracing dye over wing shapes in a low-turbulence water channel. Unlike any other experiment to date, the variation in sweep was the only parameter change, all others being fixed. The airfoil shape was a cambered plate, which is close to optimal at ... |
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| Variability and Model Adequacy in Simulations of Store-Induced Limit Cycle Oscillations |
03 MAY 2007 |
48 pages |
| Authors:
Ashley S. Myers; NAVAL ACADEMY ANNAPOLIS MD
|
| A prominent phenomenon of the transonic flight regime is the potential for limit cycle oscillation (LCO) development. LCO is a stable oscillation produced by aeroelastic interactions within a component of the aircraft. Such oscillation shortens the fatigue life of the aircraft and increases the amount of maintenance necessary. These aspects are of great concern to the aerospace industry, particularly with high performance military aircraft that are required to operate beyond ... |
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| Shot-Peening Sensitivity of Aerospace Materials |
MAY 2007 |
154 pages |
| Authors:
Scott Grendahl; Daniel Snoha; Benjamin Hardisky; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| The U.S. Army Aviation and Missile Research Development and Engineering Command (AMRDEC), Aviation Engineering Division in Huntsville, AL requested that the U.S. Army Research Laboratory, Weapons and Materials Research Directorate at Aberdeen Proving Ground, MD develop and execute a program aimed at evaluating the shot-peening sensitivity of several aerospace materials. The materials represent the four most common metals utilized on U.S. Army aviation shot-peened components. The study had three main ... |
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| Assessment of TEM Cells for Whole Aircraft EMV Testing |
MAY 2007 |
|
| Authors:
Andrew J. Walters; Chris Leat; DEFENCE SCIENCE AND TECHNOLOGY ORGANISATION EDINBURGH (AUSTRALIA) AIR OPERATIONS DIV
|
 | Transverse Electromagnetic (TEM) cells offer one solution to the problem of electromagnetic vulnerability (EMV) testing of whole vehicles at lower frequencies. Combined with a reverberation chamber (RC) TEM cells offer an attractive solution to a EMV testing facility which could operate in the frequency range of 10 kHz to 18 GHz. In order to move toward a hybrid RC/TEM facility the non-uniform transition region between TEM and RC operation (i.e. ... |
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| Falco UAV Low Reynolds Airfoil Design and Testing at Galileo Avionica |
01-Apr-2007 |
25 pages |
| Authors:
Luca Cistriani; GALILEO AVIONICA RONCHI DEI LEGIONARI (ITALY) SIMULATORS AND UAV BUSINESS UNIT
|
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| A Review of Australian and New Zealand Investigations on Aeronautical Fatigue During the Period April 2005 to March 2007 |
APR 2007 |
|
| Authors:
Graham Clark; DEFENCE SCIENCE AND TECHNOLOGY ORGANISATION VICTORIA (AUSTRALIA) AIR VEHICLES DIV
|
| This document has been prepared for presentation to the 30th Conference of the International Committee on Aeronautical Fatigue scheduled to be held in Naples, Italy, 14th and 15th May 2007. Brief summaries and references are provided on the aircraft fatigue research and associated activities of research laboratories, universities, and aerospace companies in Australia and New Zealand during the period April 2005 to March 2007. The review covers fatigue-related research programs ... |
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| Fluidic Control of Virtual Aerosurfaces |
APR 2007 |
71 pages |
| Authors:
Ari Glezer; GEORGIA INST OF TECH ATLANTA SCHOOL OF MECHANICAL ENGINEERING
|
| This experimental research has focused on modifying the global aerodynamic characteristics of lifting surfaces at cruise (low) angles of attack when the baseline flow is fully attached. Using hybrid actuators, trapped vorticity concentrations at the leading and trailing edges affect aerodynamic forces and moment without control surfaces. Hybrid actuators employ miniature obstructions with integrated synthetic jet actuators. Actuation on the pressure surface near the leading edge results in a substantial ... |
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| Finite Element Solution: Nonlinear Flapping Beams for Use with Micro Air Vehicle Design |
MAR 2007 |
122 pages |
| Authors:
Robert L. Walker; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| The development and use of Micro Air Vehicles is becoming more and more important to the military. Size, weight, maneuverability, stealth, and fuel consumption are just some of the constraints on a future Micro Air Vehicle. Perfect blueprints for a small scale flying machine are both insects and humming birds. Medium sized hummingbirds are found to have wings-beats at a frequency of 18-28 Hz. There is a vast amount of ... |
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| Experimental Investigation of Oblique Wing Aerodynamics at Low Speed |
MAR 2007 |
104 pages |
| Authors:
Matthew J. Dillsaver; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| In an effort to increase the range of missiles and guided bombs, the USAF is looking at options for new wing configurations. One such configuration being considered is oblique wings. An oblique wing is a wing that pivots about a point on the aircraft fuselage thereby having one side swept forward and the other swept aft. Additional interest is looking at a wing only configuration that also rotates with one ... |
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| Parametric Reduced-Order Models for Probabilistic Analysis of Unsteady Aerodynamic Applications |
2007 |
16 pages |
| Authors:
T. Bui-Thanh; K. Wilcox; O. Ghattas; MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| Methodology is presented to derive reduced-order models for large-scale parametric applications in unsteady aerodynamics. The specific case considered in this paper is a computational fluid dynamic (CFD) model with parametric dependence that arises from geometric shape variations. The first key contribution of the methodology is the derivation of a linearized model that permits the effects of geometry variations to be represented with an explicit affine function. The second key contribution ... |
|
| A Summary of the 2006 Overset Symposium on Composite Grids and Solution Technology |
31 DEC 2006 |
3 pages |
| Authors:
Darby J. Vicker; Eric G. Paterson; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HOUSTON TX LYNDON B JOHNSON SPACE CENTER
|
| The Symposium on Overset Composite Grids and Solution Technology is a bi-annual international meeting focused on the use of overset grid technology in numerical solutions. It provides an open communication forum for mathematicians, scientists, and engineers from academia, industry, and government who are working with or interested in using the overset grid approach. The specific goals of the symposium are as follows: to communicate recent work, new research ideas, and ... |
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| Active Flutter Suppression Using Cooperative, High Frequency, Dynamic-Resonant Aero-Effectors |
13 DEC 2006 |
36 pages |
| Authors:
William D. Armstrong; William R. Lindberg; John E. McInroy; Jonathan W. Naughton; WYOMING UNIV LARAMIE COLL OF ENGINEERING
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| An investigation of the use of actuators that cause aerodynamic disturbances that could be used for flutter control was investigated. Flutter control requires large disturbances to produce the aerodynamic loads needed to oppose the flutter forces. As a result, oscillating fence actuators that have low power consumption and high control authority that scales with flight speed were studied. These fence actuators were tested in laminar and turbulent boundary layers to ... |
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| Process Improvement at the Aircraft Intermediate Maintenance Detachment (AIMD) at Naval Air Station Whidbey Island |
DEC 2006 |
123 pages |
| Authors:
Eric Jafar; Terence N. Mejos; Chieh Yang; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| This project focuses on the J52-P408 engine repair process and the implementation of the "AIRSpeed" program at the Aircraft Intermediate Maintenance Department (AIMD) at Naval Air Station Whidbey Island (NASWI), WA. The project was conducted with the sponsorship and assistance of Program Executive Office Ships (PEO SHIPS) and Program Executive Office Integrated Warfare Systems (PEO IWS). The goal of this project is to analyze how the leadership of AIMD incorporated ... |
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| Computational Investigation of Flapping-Wing Propulsion for a Micro-Air Vehicle |
DEC 2006 |
109 pages |
| Authors:
Seng C. Lim; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| The low Reynolds number aerodynamics of the flapping-wing Micro-Air Vehicle (MAV) developed at NPS by Max Platzer and Kevin Jones was studied numerically. The dynamic mesh simulation model of the full multi-wing configuration, which consists of a fixed wing and a pair of aft position, opposed pitch/plunge flapping wings was developed using an advanced CFD code that is available commercially. The unsteady Navier-Stokes flow fields, wake structures and forces variations ... |
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Aerodynamics
