| Application of Quantum Chemical Approximations to Environmental Problems: Prediction of Water Solubility for Nitro Compounds |
10-Nov-2009 |
9 pages |
| Authors:
Mohammad Qasim; Jerzy Leszczynski; Yana A Kholod; Eugene N Muratov; Leonid G Gorb; Frances C Hill; Anatoly G Artemenko; Victor E Kuz'min; JACKSON STATE UNIV MS DEPT OF CHEMISTRY
|
 | Water solubility values for 27 nitro compounds with experimentally measured values were computed using the conductor-like screening model for real solvent (COSMO-RS) based on the density functional theory and COSMO technique. We have found that the accuracy of the COSMO-RS approach for prediction of water solubility of liquid nitro compounds is impressively high (the errors are lower than 0.1 LU). However, for some solid nitro compounds, especially nitramines, there is ... |
|
| Rewriting History: Historical Research With the Digital Plan |
Oct-2009 |
18 pages |
| Authors:
Molly Marshall; Lauren Scharff; AIR FORCE ACADEMY COLORADO SPRINGS CO INST FOR INFORMATION TECHNOLOGY APPLICATIONS
|
| This study examined the use of technology to enhance the educational experience. The study, which involved 28 Cadets from the United States Air Force Academy, was designed to examine the benefits of using a digital pen for note taking in the classroom. The Department of History offers a Historiography and Methods class (History 330), where cadets research historical data. The cadets plan, research and write a 5000-7000 word term paper. ... |
|
| Attempts to Create Ball Lightning with Triggered Lightning |
Oct-2009 |
33 pages |
| Authors:
Jonathan D Hill; Martin A Uman; Michael Stapleton; Douglas M Jordan; Alexander M Chebaro; Christopher J Biagi; FLORIDA UNIV GAINESVILLE DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
|
| During the 2008 ball lightning experiment, around 100 different material samples were exposed to both relatively continuous (initial stage and inter-stroke continuing current) and to impulsive (return stroke) triggered lightning current. All events with properties similar to those reported by eye-witness and laboratory accounts of ball lightning were produced by slowly varying, relatively low amplitude currents during the initial stage of the triggered-lightning process. No events with sustained luminosity duration ... |
|
| Predicting Electron Transport Using Simulated Axial Waves in a Radial-Axial Hybrid Hall Thruster Model |
Sep-2009 |
12 pages |
| Authors:
Michelle K Scharfe; Mark A Cappelli; Eduardo Fernandez; ENGINEERING RESEARCH AND CONSULTING INC (ERC INC) EDWARDS AFB CA
|
| Axial waves predicted by a two-dimensional hybrid numerical model have been used to estimate electron cross field transport due to tilted waves with azimuthal components. Since the radial-axial hybrid simulation cannot model these tilted waves directly, the predicted axial waves are assumed to couple symmetrically into two counter-propagating axial-azimuthal waves. A linearized two-dimensional dispersion relation is solved to obtain the azimuthal component of wavenumber consistent with the frequency and axial ... |
|
| Effect of Wall Sheaths on Ion Trajectories in a Hall Thruster Numerical Model |
Sep-2009 |
12 pages |
| Authors:
Regina M Sullivan; Joseph E Shepherd; Michelle K Scarfe; Ioannis G Mikellides; Lee K Johnson; CALIFORNIA INST OF TECH PASADENA
|
| A 2D framework for solving the sheath equations near a dielectric corner has been developed and applied in a quasi 2D fashion to solve for sheath thickness and potential profile. When appropriate, boundary conditions were taken from an HPHall model of an SPT-70 Hall thruster. Ion paths within the sheath were also calculated. Results suggest that the radial acceleration provided by the sheath has the ability to produce significant changes ... |
|
| Genetic Algorithms in the Battlespace Terrain Reasoning and Awareness-Battle Command (BTRA-BC) Battle Engine |
Sep-2009 |
118 pages |
| Authors:
Kenneth J Maroon; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The U.S. Army Corps of Engineers Research and Development Center's (ERDC) Battlespace Terrain Reasoning and Awareness-Battle Command (BTRA-BC) Battle Engine (BBE) is a tool that enables command staffs to semi-automate the creation and evaluation of potential courses of action (COA) for use in military planning. The BBE uses data generated during the initial steps of the Military Decision Making Process (MDMP) and a genetic algorithm to produce and evaluate a ... |
|
| CFD Prediction of Magnus Effect in Subsonic to Supersonic Flight |
Sep-2009 |
46 pages |
| Authors:
James DeSpirito; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| The aerodynamic coefficients of the 7-cal. U.S. Army-Navy Spinner Rocket were characterized using computational fluid dynamic (CFD) calculations and validated using archival experimental data. The static aerodynamic coefficients, roll-damping, and pitch-damping moments were accurately predicted by steady-state Reynolds-averaged Navier-Stokes (RANS) as well as unsteady hybrid RANS/large-eddy simulation (LES) CFD. The Magnus moment was overpredicted in the subsonic and transonic regime. Unsteady RANS/LES computations did not improve the prediction of Magnus ... |
|
| Numerical Optimization of an Annular Field Reserved Configuration Translation Experiment |
14-Aug-2009 |
16 pages |
| Authors:
Lyon B King; Carrie S Niemela; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Annular field reversed configuration (AFRC) devices form annular plasma toroids between a pair of concentric cylindrical coils. This plasmoid remains detached from the external magnetic _field so that it can be ejected from the coils, making AFRCs viable pulsed inductive plasma accelerators. Though numerous formation studies on AFRCs are available, no successful translation studies have been published. Michigan Technological University, in conjunction with the Air Force Research Laboratory, is investigating ... |
|
| Dynamic Behavior of Nano-Sized Particles in Novel Energetic Materials for Space Propulsion |
11-Aug-2009 |
45 pages |
| Authors:
Thomas L Jackson; Steven F Son; William A Dick; ILLINOIS UNIV AT URBANA-CHAMAPAIGN
|
| We report a comprehensive computational and experimental program investigating the characteristics and dynamic behavior of nano-size aluminum in novel energetic materials. For the computational portion, we employed (1) our in-house packing code, Rocpack, to generate morphologies of interest for heterogeneous propellants; (2) modified our solid rocket motor CFD code, Rocstar, to include appropriate models for chemistry, radiation, and nano-sized aluminum; and (3) simulated transient behavior of the propellants at rocket ... |
|
| Ankudinov Ship Squat Predictions - Part 2: Laboratory and Field Comparisons and Validations |
Aug-2009 |
21 pages |
| Authors:
Michael J Briggs; Larry Daggett; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
|
| This Coastal and Hydraulics Engineering Technical Note (CHETN) is a continuation of the earlier CHETN entitled, Ankudinov ship squat predictions - Part I: Theory and FORTRAN programs, CHETN-IX-19 (Briggs 2009) that documented the Ankudinov squat formulas and described two FORTRAN programs for single and multiple ship speed applications. It also compared the Ankudinov formula with several of the PIANC empirical squat formulas for a Panamax bulk carrier and tanker. This ... |
|
| Steam-jet Chiller for Army Field Kitchens |
Aug-2009 |
60 pages |
| Authors:
David Brownell; YANKEE SCIENTIFIC INC MEDFIELD MA
|
| Report developed under Broad Agency Announcement. This report documents a two-year project aimed at developing steam-jet refrigeration technology that can be integrated with superheated-liquid injection cogeneration (SLIC) cycles in Army kitchens or with MesoScale Steam Engine Generators (MSEGs). During the first year, focus was on designing a flexible laboratory platform suitable for developing and testing steam-jet hardware. In the second year, the test stand was enhanced to provide for semi-automatic ... |
|
| Biologically Inspired Nano-Contact Mechanics |
20-Jul-2009 |
19 pages |
| Authors:
Pradeep R Guduru; BROWN UNIV PROVIDENCE RI DIV OF ENGINEERING
|
| The objective of this project was to investigate the mechanics aspects of biological adhesion and friction mechanisms of small animals and insects and to extract canonical principles that can help design synthetic surface micro-architectures that can mimic the exceptional adhesion capabilities of these animals. Our approach included theoretical modeling, experimental validation of the models and fabrication & testing of microstructures. Significant progress has been made in developing a fundamental mechanistic ... |
|
| Spray Nonuniformities in Gas-Centered Swirl-Coaxial Injectors (Preprint) |
Jul-2009 |
7 pages |
| Authors:
Malissa D Lightfoot; Stephen A Danczyk; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Experimental studies of gas-centered swirl-coaxial (GCSC) injectors have revealed five basic types of nonuniformities in the spray. These nonuniformities can be classified as either affecting the centerline of the spray, with respect to the centerline of the injector, or affecting the temporal mass-distribution. The details of these behaviors are discussed as are possible driving factors and design criteria for avoidance. In general, high momentum flux operations are suggested for minimizing ... |
|
| Assessment of the Performance of Iodine-Treated Biocidal Filters and Characterization of Virus Aerosols |
Jul-2009 |
142 pages |
| Authors:
Jin-Hwa Lee; FLORIDA UNIV GAINESVILLE DEPT OF ENVIRONMENTAL ENGINEERING SCIENCES
|
| Enhanced awareness of the threat of biological warfare and the spread of airborne pathogens has stimulated interest in bioaerosols and the need to develop better methods for respiratory protection. Among pathogens, viruses and bacterial spores are of special concern because they exhibit resistance to inactivation, small (highly penetrating) particle size and low median infectious dose. This study compared the mechanical and total viable removal by a relatively inefficient (N50) iodine-treated ... |
|
| Checkpoint Functions of the BRCA1/BARD1 Tumor Suppressor |
Jul-2009 |
34 pages |
| Authors:
Ami Modi; COLUMBIA UNIV NEW YORK
|
| The tumor suppressor BRCA1 has been implicated in numerous cellular processes, including cell cycle checkpoint control, DNA repair, and mitotic spindle assembly. In vivo, BRCA1 primarily exists in association with BARD1, and the BRCA1/BARD1 heterodimer is thought to mediate the tumor suppression activity of BRCA1. It has been shown that the phosphorylation state of the BARD1 polypeptide is cell- cycle regulated and that BARD1 is hyperphosphorylated in mitosis at seven ... |
|
| Point Density Effects on Digital Elevation Models Generated from LiDAR Data |
Jun-2009 |
73 pages |
| Authors:
Richard L Duldulao; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The use of Airborne LiDAR Systems (ALS) to obtain topographical information of the earth's surface and generate Digital Elevation Models (DEMs) has grown extensively in the field of Remote Sensing. Selected areas of point cloud LiDAR data collected from Honduras in 2008 was used to produce DEMs with varying densities to show the effects of lower resolution LiDAR data. An IDL code was utilized to reduce the selected LiDAR point ... |
|
| Transport Imaging: Developing an Optical Technique to Characterize Bulk Semiconductor Materials for Next Generation Radiation Detectors |
Jun-2009 |
79 pages |
| Authors:
Sarah L Catalano; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Characterization of the mobility-lifetime product is critical to the development of new materials for semiconductor radiation detectors. An optical technique has been developed that allows for the direct determination of the minority carrier diffusion length, drift length, and mobility-lifetime product from a single image of the recombination luminescence in semiconductor materials. Excess carriers are generated using the electron beam in a scanning electron microscope. The charge is then drifted by ... |
|
| First-Principles Monte-Carlo Simulation of Homogeneous Condensation in Atomic and Molecular Plumes |
Jun-2009 |
17 pages |
| Authors:
Sergey Gimelshein; Ingrid Wysong; Ryan Jansen; Michael Zeifman; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| First-principles kinetic theory is used in this work to analyze non-equilibrium homogeneous condensation of argon and water. The present model uses a recombination-reaction energy-dependent mechanism of the DSMC method for the dimer formation, and RRK model for the evaporation. Three-step validation of the model is conducted, (i) comparison of clusterization rates in an equilibrium heat bath with theoretical predictions, (ii) comparison of the argon dimer fractions in an orifice expansion ... |
|
| Accuracy Analysis for Kinetic Modeling of Homogeneous Condensation in Plumes |
Jun-2009 |
6 pages |
| Authors:
Sergey Gimelshein; Deborah Levin; Ingrid Wysong; Ryan Jansen; Michael Zeifman; Zheng Li; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Two different approaches for modeling the clustering in rapidly expanding plumes have been reported in the literature. The first approach, known as the classical approach, takes its starting point from the classical nucleation theory (CNT) which is based on equilibrium thermodynamics. The second one, known as the kinetic approach, treats nucleation as the process of kinetic chemical aggregation. The first, macroscopic, approach, while being useful and found to be applicable ... |
|
| TNT Testbed for Self-Organizing Tactical Networking and Collaboration |
Jun-2009 |
64 pages |
| Authors:
Alex Bordetsky; David Netzer; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Beginning in 2002, a team of Naval Postgraduate School researchers together with sponsors from USSOCOM, and later joined by the OSD and DHS S&T Programs, started a new campaign of discovery and constraints analysis experiments (Alberts and Hayes, 2007), which is now collectively known as Tactical Network Topology (TNT) Experiments. This campaign of experimentation, carried out under the USSOCOMNPS Field Experimentation Cooperative program and OSD/ HLS S&T support unfolds in ... |
|
| Modeling of Defects in Transparent Ceramics for Improving Military Armor |
Jun-2009 |
14 pages |
| Authors:
C G Fountzoulas; J M Sands; G A Gilde; P J Patel; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The dominant materials solution used for ballistic transparency protection of armored tactical platforms in commercial and military applications is low cost glass backed by polycarbonate. Due to the high cost of testing transparent ceramics, a modelling approach has been undertaken in parallel with ballistic testing to validate armor designs based on a transparent magnesium aluminate spinel, MgAl2O4, striking-ply backed by polycarbonate. Finite element modelling is used to predict unsuccessful designs ... |
|
| Deceiving Adversary Network Scanning Efforts Using Host-Based Deception |
Jun-2009 |
87 pages |
| Authors:
Sherry B Murphy; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| In this research, we demonstrate the usefulness of manipulating system traffic to deceive an attacker's operating system (OS) fingerprinting as part of their network scanning efforts. Specifically, we address whether host-based OS obfuscation has merit and application as an integral part of Air Force network defense and whether the technique warrants further research and application development. We accomplish this objective through a literature review and a proof of concept evaluation ... |
|
| Characterization of Robotic Tail Orientation as a Function of Platform Position for Surf-Zone Robots |
Jun-2009 |
103 pages |
| Authors:
Courtney L Holland; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The Naval Postgraduate School Small Robot Initiative is an ongoing effort to develop autonomous robotic platforms for military applications. The latest design in this series, a quadruped robot with a tail for stability and obstacle climbing, is currently under development in collaboration with Case Western Reserve University. Tail orientation as a function of robot platform attitude is tested for angle of bank climbs at 10 and 15 degrees. Data indicate ... |
|
| Scarf Joint Modeling and Analysis of Composite Materials |
Jun-2009 |
77 pages |
| Authors:
Armando Marron; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The objective of this study is to investigate joint strength of the scarf joint configuration, constructed from carbon and glass woven fabric hybrid laminates, with different material combinations. Glass/glass, glass/carbon, carbon/glass, and carbon/carbon are tested under various loading conditions like tension, compression, bending and shear loading. Both experimental and computational studies are conducted. For the experimental study, specimens made of scarf joints using carbon and glass woven fabrics are tested ... |
|
| Initial Research on Multitask Training and Transfer: Research Issues for the Future Force |
Jun-2009 |
40 pages |
| Authors:
Peter S Schaefer; Brian T Crabb; ARMY RESEARCH INST FOR THE BEHAVIORAL AND SOCIAL SCIENCES FORT KNOX KY
|
| New technologies currently under development will provide Soldiers with unprecedented amounts of information. However, these technologies will also require Soldiers to multitask (MT) under demanding circumstances. In two experiments, Soldiers were trained to complete isolated tasks, called single task (ST) training, or a combination of tasks, called multitask (MT) training. Working memory of the participants was measured in Experiment 2. The ability of both the single task and multitask trained ... |
|
| Forward Sound Propagation Around Seamounts: Application of Acoustic Models to the Kermit-Roosevelt and Elvis Seamounts |
Jun-2009 |
279 pages |
| Authors:
Hyun J Kim; MASSACHUSETTS INST OF TECH CAMBRIDGE JOINT PROGRAM IN APPLIED OCEAN SCIENCE AND ENGINEERING
|
| The Basin Acoustic Seamount Scattering Experiment (BASSEX) of 2004 was conducted to measure forward-scattering around the Kermit-Roosevelt Seamount Complex in the Northeast Pacific. The BASSEX experiment was focused on the bathymetric effects on acoustic propagation, in particular, on direct blockage, horizontal refraction, diffraction, and scattering by the seamounts. A towed hydrophone array, with 64 sensors cut for 250Hz (3m spacing), was used to measure the signals transmitted from the aforementioned ... |
|
| Simulation of Ballistic Impact of a Tungsten Carbide Sphere on a Confined Silicon Carbide Target |
Jun-2009 |
16 pages |
| Authors:
C G Fountzoulas; B A Cheeseman; J C LaSalvia; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The present investigation is a continuation of our previous study on the ability of the phenomenological Johnson-Holmquist model to predict the observed damage induced by spheres of tungsten carbide (WC) striking confined cylinders of silicon carbide (SiC) at velocities between 63 m/s to 500 m/s. In this study, the WC was modeled using the Johnson-Cook plasticity model along with a principal stress failure criterion calibrated with recently available experimental data. ... |
|
| Small Molecule Activators of the Trk Receptors for Neuroprotection |
May-2009 |
|
| Authors:
Nicholas J Webster; VETERANS MEDICAL RESEARCH FOUNDATION SAN DIEGO CA
|
 | Our central hypothesis is that asterriquinone activators of the Trk receptors would prevent the neuronal cell death associated with traumatic brain injury and would improve cognitive and motor outcomes. We have developed agonists to TrkA and TrkB. The TrkA agonist has been tested in a preclinical model of cognitive impairment and a model of traumatic brain injury. The drug improves learning in a Morris water maze paradigm and reduces infarct ... |
|
| New Fluorinated and Sulfonated Block Copolymers Final Report |
23-Apr-2009 |
60 pages |
| Authors:
Samuel P Gido; Jimmy W Mays; Suxiang Deng; Mohammed K Hassan; Kenneth A Mauritz; MASSACHUSETTS UNIV AMHERST
|
| A new class of fluorinated and sulfonated block copolymers was synthesized and characterized with respect to morphology using TEM and small angle X-ray and neutron scattering. Proton and methanol transport properties were evaluated with a view toward using these materials for fuel cell membranes. The materials formed microphase separated morphologies, which were generally less well ordered than unfluorinated and sulfonated block copolymers. |
|
| Chemical Kinetics Interpretation of Hypergolicity of Ionic Liquid-Based Systems |
01-Apr-2009 |
43 pages |
| Authors:
Laurent Catoire; CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE ORLEANS-LA-SOURCE (FRANCE)
|
| This report results from a contract tasking Centre National de la Recherche Scientifique as follows: The prospect of hypergolically igniting Ionic Liquids (ILs) requires a detailed understanding of the underlying chemical pathways and the reaction mechanisms involved when ILs are treated with NTO or any suitable oxidizer (RFNA, WFNA). The potential to develop hypergolic ignition as a suitable option for space propulsion applications requires gas-phase thermodynamic and chemical kinetic data. ... |
|
| Chemical Modeling for Large-Eddy Simulation of Turbulent Combustion |
31-Mar-2009 |
41 pages |
| Authors:
Heinz Pitsch; LELAND STANFORD JUNIOR UNIV CA
|
| In the present project the focus was on developing advanced combustion models for large-eddy simulations (LES) and to develop automatic chemistry reduction techniques and reduced chemical mechanisms for JP-8 surrogate fuels. The aim of the combustion LES modeling part was to advance the models for non-premixed and premixed combustion towards a generalized combustion model that covers all combustion regimes. Towards this end, for the premixed regime, a dynamic model for ... |
|
| Super Maneuverable, Flapping Wing Micro-Air-Vehicles |
16-Mar-2009 |
28 pages |
| Authors:
B Balachandran; E Balaras; Marcos Vanella; Timothy Fitzgerald; Sergio Preidikman; MARYLAND UNIV COLLEGE PARK DEPT OF MECHANICAL ENGINEERING
|
| Interest in the development of super-maneuverable, micro-air-vehicles has led to the re-examination of basic flight modes, particularly, those that are inspired by biological observations. The majority of experimental and numerical studies related to flapping flight have explored the relationships between the thrust coefficient (and propulsive efficiency) and wing geometry and kinematics. Relatively speaking, the wing flexibility and the interplay between kinematics and flexibility have received less attention, and currently, it ... |
|
| Boundary Avoidance Tracking: Consequences (and Uses) of Imposed Boundaries on Pilot-Aircraft Performance |
Mar-2009 |
115 pages |
| Authors:
Ryan D Blake; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| This thesis presents the results of research into the Boundary Avoidance Tracking (BAT) theory, which states that often pilots control an aircraft not in an attempt to maintain some condition, but to avoid some real or perceived boundaries. This pilot modeling concept was studied using over 30 pilots in simulator and flight tests. The pilot-aircraft system was evaluated with 3 different lateral-directional control models. Pilots were given a roll angle ... |
|
| An Investigation of Shock Wave Physics via Hybrid CFD-BGK Solution Methods for Nonequilibrium Flows |
Mar-2009 |
92 pages |
| Authors:
Brook I Bentley; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
|
| The Unified Flow Solver, a hybrid continuum-rarefied code, is used to investigate the internal structure of a normal shock wave for a Mach range of 1.55 to 9.0 for Argon, and 1.53 to 3.8 for diatomic Nitrogen. Reciprocal shock thickness, density, temperature, heat flux, and the velocity distribution function are calculated for a one-dimensional shock wave and compared with experimental data from Alsmeyer and DSMC results from Bird. Using the ... |
|
| Dislocation Dynamic Modeling in High Temperature Single Crystal Viscoplasticity (Preprint) |
Mar-2009 |
5 pages |
| Authors:
Brice N Cassenti; Alexander Staroselsky; PRATT AND WHITNEY EAST HARTFORD CT
|
| We have developed a crystallographic-based viscoplastic model for nonisothermal high temperature deformation and coupled it with damage kinetics. Several damage mechanisms, namely the multiplication of mobile dislocations, void growth and including scale effects, caused by dislocation extrusions/intrusions, have been considered. We applied two body interaction concepts from chemical kinetics to include in our constitutive relations the generation and interaction of pinned and mobile dislocations. The relative importance of each of ... |
|
| Development of the 2007 Chemical Decontaminant Source Document |
Mar-2009 |
|
| Authors:
Teri Lalain; Brent Mantooth; Zach Zander; Pamela Humphreys; Tom Lynn; SCIENCE APPLICATIONS INTERNATIONAL CORP GUNPOWDER MD
|
| The chemical decontaminant performance evaluation testing source document is the product of project BA06DEC414 for improved test methodology. The primary objective is to improve the rigor of existing test methods for the generation of defensible and comparable decontamination efficacy data for the quantitative determination of post-decontamination contact and vapor hazards and residual agent. Execution of these improved methods will yield higher fidelity data presented in appropriate context. The data generated ... |
|
| Experimental/Computational Approach to Accommodation Coefficients and its Application to Noble Gases on Aluminum Surface (Preprint) |
03-Feb-2009 |
26 pages |
| Authors:
Andrew Ketsdever; Sergey F Gimelshein; Nathaniel Selden; Natalie E Gimelshein; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| A technique is proposed to assess gas-surface accommodation coefficients. The technique utilizes the fact that radiometric forces exerted on heated objects immersed in rarefied gases are governed by the interaction of gas molecules with the surface. In the present implementation, it connects measurements of radiometric forces on a heated vane in the transitional flow regime with the kinetic modeling of the flow, and derives the accommodation coefficients through the successive ... |
|
| Computational Prediction of Kinetic Rate Constants |
Feb-2009 |
27 pages |
| Authors:
Mark Ponton; Rodney J Bartlett; ACES QC LC GAINESVILLE FL
|
| The objective of this STTR has been to develop tools to make the evaluation of rate constants for gas phase reactions routine for many modest sized molecules. such quantities are critical input to atmospheric and combustion models. they also provide critical information to designing procedures to destroy stock piles of nerve agents, and other waste products. However, it is often very difficult to experimentally measure such rate constants, making 'predictive' ... |
|
| Experimental and Numerical Analysis of Radiometric Forces on a Heated Circular Vane in Argon (Preprint) |
13-Jan-2009 |
16 pages |
| Authors:
N Gimelshein; S Gimelshein; N Selden; C Ngalande; A Ketsdever; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Radiometric force on a 0.12m circular vane is studied experimentally and numerically over a wide range of pressures that cover the flow regimes from near free molecular to near continuum. In the experiment, the vane is resistively heated to about 419 K on one side and 394 K on the other side, and immersed in a rarefied argon gas. The radiometric force is then measured on a nano- Newton thrust ... |
|
| Integrated Computational/Experimental Study of Turbulence Modification and Mixing Enhancement in Swirling Jets |
07-Jan-2009 |
30 pages |
| Authors:
J Naughton; D Stanescu; S Heinz; R Semaan; M Stoellinger; C Zemtsop; WYOMING UNIV LARAMIE
|
| Swirling jet flows have been studied experimentally and computationally and the results have been compared with theory. Three-component Laser Doppler Anemometry (LDA) measurements have been carried out for swirling jets of various strengths and swirl distributions. Radial profiles of velocity have been obtained from the jet exit to 50 diameters downstream. The experimental results are consistent with previous results and with similarity theory for weakly swirling turbulent jets. However, the ... |
|
| Wave Transformation Over Reefs: Evaluation of One-Dimensional Numerical Models |
Jan-2009 |
208 pages |
| Authors:
Zeki Demirbilek; Alejandro Sanchez; Okey G Nwogu; Donald L Ward; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
|
| Three one-dimensional (1D) numerical wave models are evaluated for wave transformation over reefs and estimates of wave setup, runup, and ponding levels in an island setting where the beach is fronted by fringing reef and lagoons. The numerical models are based on different governing equations. BOUSS-1D and RBREAK2 are phase-resolving models that respectively solve the time-dependent Boussinesq and shallow water equations. WAV1D solves the 1D wave-averaged energy conservation equation. Laboratory ... |
|
| Transport Processes in Reacting Hydrothermal Flames with Applications to Military Waste Destruction in Supercritical Water and Geotechnical Rock Excavation |
Jan-2009 |
17 pages |
| Authors:
J W Tester; C Augustine; MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CHEMICAL ENGINEERING
|
| A hydrothermal flame is a flame that exists in a supercritical aqueous medium and is characterized by steep temperature and density gradients. The overall objective of our project was to increase understanding of heat, mass, and momentum transport processes within hydrothermal flames. Specifically, we planned to study hydrothermal flame characteristics such as flame temperature and stability, and to develop a method for modeling heat and mass transport processes in the ... |
|
| Canopy Penetration and Deposition of Barrier Sprays from Electrostatic and Conventional Sprayers |
Jan-2009 |
10 pages |
| Authors:
W C Hoffmann; J Hogsette; U Bernier; B Fritz; M Farooq; Y Huang; Y Lan; B Quinn; D Szumlas; V L Smith; T W Walker; C A Robinson; AGRICULTURAL RESEARCH SERVICE COLLEGE STATION TX
|
| An experimental study was conducted to investigate the usefulness of electrostatic and conventional sprayers for barrier applications. Two conventional and three electrostatic sprayers were used in the study. Usefulness of the sprayers was rated based on penetration of spray into and deposition onto 2 sides of leaves on natural vegetation. Bifenthrin (TalstarTM adulticide) was applied at labeled rate, fluorescent dye was added to the tank mix as tracer, and all ... |
|
| Equivalent Roughness Height for Plane Bed Under Oscillatory Flow |
Jan-2009 |
15 pages |
| Authors:
Magnus Larson; Benoit Camenen; Atilla Bayram; CEMAGREF LYON (FRANCE)
|
| A new relationship between the roughness height and the main hydrodynamic and sediment parameters for plane beds under oscillatory conditions is presented. In order to derive such a relationship, a large data base encompassing plane-bed experiments was compiled from previous investigations and analyzed. Different methods to estimate the roughness height were investigated. Comparisons between the data and different existing predictive formulas for the bed roughness obtained from the literature were ... |
|
| Lamb Wave Dispersion Compensation in Piezoelectric Wafer Active Sensor Phased-Array Applications |
Jan-2009 |
|
| Authors:
Victor Giurgiutiu; Buli Xu; Lingyu Yu; SOUTH CAROLINA UNIV COLUMBIA DEPT OF MECHANICAL ENGINEERING
|
| Lamb-wave testing for structural health monitoring is complicated by the dispersion nature of the wave modes. The dispersion effect will result in a propagated wave with longer time duration, deformed envelop shape as compared to its excitation counterpart, and hard to be interpreted. This paper first reviews the dispersion compensation and removal algorithms. Second, it compares these two methods by applying them to two widely used low-frequency Lamb wave modes: ... |
|
| A New Approach for Investigating Crystal Stresses that Drive the Initiation of Fatigue-Induced Defects in Structural Alloys |
31-Dec-2008 |
15 pages |
| Authors:
Paul R Dawson; CORNELL UNIV ITHACA NY
|
| We have developed an approach to investigate crystals stresses during cyclic load by coordinating experiments and simulations at the size scale where fatigue induced defects initiate. Our efforts provided new understanding of the stress evolution during cyclic loading through a complementary process between the experimental measurement of lattice strain and the simulation results. The comparison of the experimental and the simulated lattice data culminated in a novel picture of how ... |
|
| Transition Delay in Hypervelocity Boundary Layers by Means of CO2/Acoustic Instability Interactions |
08-Dec-2008 |
52 pages |
| Authors:
Graham Candler; Ivett A Leyva; Stuart Laurence; Amy W Beierholm; Hans G Hornung; Ross Wagnild; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| A novel method to delay transition in hypervelocity flows over slender bodies by injecting CO2 into the boundary layer of interest is investigated. The results presented here consist of both experimental and computational data. The experimental data was obtained at Caltech's T5 reflected shock tunnel, while the computational data was obtained at the University of Minnesota. The experimental model was a 5 degree sharp cone, chosen because of its relevance ... |
|
| Generic UAV Modeling to Obtain Its Aerodynamic and Control Derivatives |
Dec-2008 |
123 pages |
| Authors:
Choon S Chua; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| This thesis deals with two different software packages to obtain the aerodynamic and control derivatives for a generic unmanned air vehicle (UAV). These data has a dual application. Firstly, it is required in the Mathworks Simulink 6-degree-of-freedom model of a generic unmanned air vehicle to develop a robust controller and do a variety of trade-offs. Secondly, is also needed to tune the parameters of the existing real-time controllers such as ... |
|
| Aerodynamic Predictions, Comparisons, and Validations Using MissileLab and Missile Datcom (97) |
Dec-2008 |
51 pages |
| Authors:
Hoon H Teo; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Aerodynamic prediction software is often used in the early stages of missile systems designed to quickly and accurately estimate the aerodynamics of a wide variety of missile configuration designs operating over many different flight regimes. It is also possible to use these empirical packages to validate flight data collected from wind tunnel tests and other open sources. Analysis of such data provides users with insights to the performance of a ... |
|
| Development of Carbon/Carbon Composites with Through-Thickness Carbon Nanotubes for Thermal and Structural Applications |
Dec-2008 |
34 pages |
| Authors:
Zhiyong (Richard) Liang; Chuck Zhang; FAMU/FSU COLL OF ENGINEERING TALLAHASSEE FL DEPT OF INDUSTRIAL ENGINEERING
|
| Carbon/carbon composites offer lightweight thermal protection capable of producing excellent thermal materials. To further improve the thermal conductivity along the thickness direction and the interlaminar shear strength, we studied and demonstrated a novel method to stitch carbon nanotube yarns along the through-thickness direction of carbon fiber two-dimensional precursor felt perform to make novel 3D reinforced carbon/carbon (C/C) composites. By stitching nanotube yarns, high strength and thermal conductive CNTs were incorporated ... |
|
Reports by Keyword(s)
EXPERIMENTAL DATA
