| Investigation on the Solubility of GaN in Supercritical Ammonia Containing Acidic, Neutral, and Some Basic Mineralizers |
19-Feb-2009 |
5 pages |
| Authors:
Dirk Ehrentraut; TOHOKU UNIV SENDAI (JAPAN)
|
 | The ammonothermal growth technique to fabricate large size (2 inch) gallium nitride (GaN) crystals has recently seen increased interest due to the achievements in the technique published over the last 2-3 years. The first ever 2 inch GaN bulk crystal, to be reported in the April 2009 issue of MRS Bulletin, holds the great promise that ammonothermally produced GaN may become an important GaN substrate material due to the superior ... |
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| Acoustic Excitation of Liquid Fuel Droplets and Coaxial Jets |
Jan-2009 |
271 pages |
| Authors:
Juan I Rodriguez; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| This experimental study focuses on two important problems relevant to acoustic coupling with condensed phase transport processes, with special relevance to liquid rocket engine and airbreathing engine combustion instabilities. The first part of this dissertation describes droplet combustion characteristics of various fuels during exposure to external acoustical perturbations. Methanol, ethanol, a liquid synthetic fuel derived from coal gasification via the Fischer-Tropsch process, and a blend of aviation fuel and the ... |
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| Fuel Composition Analysis of Endothermically Heated JP-8 Fuel for Use in a Pulse Detonation Engine |
JUN 2008 |
124 pages |
| Authors:
Eric A. Nagley; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
|
| Waste heat from a pulse detonation engine (PDE) was extracted via zeolite catalyst coated concentric tube-counter flow heat exchangers to produce supercritical pyrolytic conditions for JP-8 fuel. A sampling system and method were developed that enabled samples of reacted fuel to be extracted during steady state operation. Samples were taken over a range of heat exchanger exit temperatures from 820 K (1016 F) to 940 K (1232 F). Offline analysis ... |
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| Evaluation of Catalytic and Thermal Cracking in a JP-8 Fueled Pulsed Detonation Engine (Postprint) |
SEP 2007 |
15 pages |
| Authors:
Timothy M. Helfrich; Frederick R. Schauer; Royce P. Bradley; John L. Hoke; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
|
| Pulsed detonation engines (PDEs) depend on rapid ignition and transition from deflagration to detonation. The prospect of converting the PDE from experimental to operational use necessitates a considerable reduction in the time required to ignite and detonate a liquid hydrocarbon fuel in air, such as JP-8. This research effort is focused on PDE operation enhancements using dual detonation tube, concentric-counter-flow heat exchangers to elevate the fuel temperature levels sufficiently to ... |
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| Raman Scattering Study of Supercritical Bi-Component Mixtures Injected into a Subcritical Environment |
SEP 2007 |
154 pages |
| Authors:
Young M. An; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| This research studies the species distribution profiles of methane/ethylene bi-components at downstream locations filled with subcritical nitrogen in a closed chamber. Unique thermodynamic and transport properties of supercritical fluids along with phase transition phenomena during fuel injection process can significantly change combustion characteristics inside a scramjet combustor. Plume properties of supercritical jets are of great interests to the studies of fuel/air mixing and subsequent combustion. The primary goal of this ... |
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| Lateral Inflow into High-Velocity Channels |
SEP 2007 |
11 pages |
| Authors:
Richard L. Stockstill; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
|
| This Coastal and Hydraulics Engineering Technical Note (CHETN) investigates lateral flow discharging into a high-velocity channel. The results of a series of laboratory and numerical model experiments are presented. Various geometric and hydraulic conditions were studied to evaluate hydraulic variables such as location and magnitude of peak depths. This depth information is necessary for determination of channel wall heights required to contain flows in the vicinity of laterals. |
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| Advanced, Non-Toxic, Anti-Corrosion, Anti-Fouling and Foul-Release Coatings Based on Covalently Attached Monolayers, Multilayers and Polymers |
08 AUG 2007 |
6 pages |
| Authors:
Thomas J. McCarthy; MASSACHUSETTS UNIV AMHERST DEPT OF POLYMER SCIENCE AND ENGINEERING
|
| This report describes 7 publications that led from this grant: Buried Interface Modification Using Supercritical Carbon Dioxide, Controlled Growth of Silicon Dioxide from "Nanoholes" in Silicon-Supported Tris(trimethylsiloxy)silyl Monolayers, Adsorption of Poly(vinyl alcohol) onto Hydrophobic Substrates (2 papers), A General Approach for Hydrophilizing and Chemically Activating Surfaces, Chemical Surface Modification of Poly(p-xylylene) Thin-Films, Nylon Surface Modification (2 papers). |
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| Dark Core Analysis of Coaxial Injectors at Sub-, Near-, and Supercritical Pressures in a Transverse Acoustic Field (Postprint) |
13 JUN 2007 |
19 pages |
| Authors:
Ivett A. Leyva; Douglas Talley; Bruce Chehroudi; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
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| An experimental study on the effects of an externally-imposed transverse acoustic field in a N2 shear coaxial jets at sub-, near-, and supercritical pressures is presented. Such fields and their interaction with the jets (i.e., breakup, mixing, etc.) are believed to play a critical role during combustion instabilities in liquid rocket engines. The shear coaxial injector used here is similar to those used in cryogenic liquid rockets. By using N2 ... |
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| Numerical Simulation of Hydrothermal Salt Separation Process and Analysis and Cost Estimating of Shipboard Liquid Waste Disposal |
Jun-2007 |
96 pages |
| Authors:
Andrew R Hunt; MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF MECHANICAL ENGINEERING
|
| Due to environmental regulations, waste water disposal for US Navy ships has become a reguirement which impacts both operations and the US Navy's budget. In 2006, the cost for waste water disposal Navy-wide was 54 million dollars, There are many advanced waste water treatment technologies in the research and development stage at academic institutions, private corporations, and government labs. Additionally, considerable progress has been made in installing and operating unigue ... |
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| Assessing the West Ridge of Luzon Strait as an Internal Wave Mediator |
2007 |
16 pages |
| Authors:
Shenn-Yu Chao; Dong-Shan Ko; Ren-Chien Lien; Ping-Tung Shaw; NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV
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| The Luzon Strait is blocked by two meridional ridges at depths, with the east ridge somewhat higher than the west ridge in the middle reaches of the Strait. Previous numerical models identified the Luzon Strait as the primary generation site of internal M2 tides entering the northern South China Sea (Niwa and Hibiya, 2004), but the role of the west-versus-east ridge was uncertain. We used a hydrostatic model for the ... |
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| A Rocket-Like Coaxial Injector in an Acoustic Field Under Sub- and Supercritical Conditions |
03 JUL 2006 |
9 pages |
| Authors:
D. W. Davis; Bruce Chehroudi; Douglas G. Talley; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| An experimental investigation was undertaken under non-reacting condition to gain a physical understanding of the interaction of acoustic waves and a coaxial-jet injector similar to those used in cryogenic liquid rockets. Liquid nitrogen (the round inner jet) and gaseous nitrogen (the annular outer jet) were used under subcritical, near critical, and supercritical chamber pressures, with and without presence of an external acoustic field. High-speed imaging provided information on the dynamic ... |
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| On the Behavior of a Shear-Coaxial Jet, Spanning Sub- to Supercritical Pressures, with and without an Externally Imposed Transverse Acoustic Field |
MAY 2006 |
262 pages |
| Authors:
Dustin W. Davis; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL AND NUCLEAR ENGINEERING
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| In the past, liquid rocket engines (LRE) have experienced high-frequency combustion instability, which impose an acoustic field in the combustion chamber. The acoustic field interacts with the fluid jets issuing from the injectors, thus altering the behavior of the jet compared to that of stable operation of the LRE. It is possible that this interaction could be a substantial feed back mechanism driving the combustion instability. In order to understand ... |
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| Behavior of a Rocket-Like Coaxial Injector in an Acoustic Field |
MAY 2006 |
13 pages |
| Authors:
D. W. Davis; B. Chehroudi; D. G. Talley; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| A non-reacting-flow experimental investigation was undertaken to gain a better understanding of some of the underlying physics associated with the interaction of acoustic waves and a coaxial-jet injector similar to those used in cryogenic liquid rockets. Liquid nitrogen (the round inner jet) and gaseous nitrogen (the annular outer jet) were used under subcritical, near critical, and supercritical chamber pressures, with and without acoustic excitation. High-speed digital imaging provided information on ... |
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| Pulse Detonation Physiochemical and Exhaust Relaxation Processes |
MAY 2006 |
44 pages |
| Authors:
Frederick R. Schauer; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
|
| The objective of this program is to establish the scientific knowledge of detonation initiation, propagation, and blow-down needed to develop a pulse detonation engine (PDE) that will function on hydrocarbon fuels. The complex interaction of chemistry, gas dynamics, turbulent mixing, and geometry are responsible for the success or failure of the detonation phenomena required to operate a PDE. Detonation tube exhaust blow-down conditions, which are predicted to have a significant ... |
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| Supercritical Hydrocarbon Impinging Injector Simulation Facility |
APR 2006 |
7 pages |
| Authors:
Michael M. Micci; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF AEROSPACE ENGINEERING
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| A supercritical hydrocarbon impinging injector simulation facility was procured and installed to increase the available computational capability to conduct molecular dynamics simulations of supercritical impinging injectors using hydrocarbon propellants. Supercritical impinging injectors using hydrocarbon propellants are of interest to the next generation of liquid propellant rocket engines. The procured high performance computing cluster allows simulations to be conducted in a sufficiently short time period to allow investigation of the effects ... |
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| Cycle Performance of a Pulse Detonation Engine with Supercritical Fuel Injection |
23 MAR 2006 |
188 pages |
| Authors:
Timothy M. Helfrich; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
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| Pulse detonation engines (PDE) rely on rapid ignition and formation of detonation waves. Because hydrocarbon fuels are composed typically of long carbon chains that must be reduced in the combustion process, it would be beneficial to create such reduction prior to injection of fuel into the engine. This study focused on PDE operation enhancements using dual detonation tube, concentric-counter-flow heat exchangers to elevate the fuel temperature up to supercritical temperatures. ... |
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| Embedding Luminescent Nanocrystals in Silica Sol-Gel Matrices |
2006 |
|
| Authors:
Lindsey M. Sorensen; FLORIDA STATE UNIV TALLAHASSEE COLL OF ARTS AND SCIENCES
|
 | We have synthesized stable, highly luminescent silica xerogels as well as optically transparent, stable aerogels that were embedded with 2.5 nm and 6 nm CdSe and 6 nm InP quantum dots. By capping the quantum dot with 3-aminopropyltriethoxysilane, a dot is able to condense within the structure of a forming silica gel. This network keeps the quantum dot in place during the solvent exchange procedure necessary to form low-density silica ... |
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| Ultrafast Multi-Dimensional Infrared Spectroscopy of Gases at Low and High Pressures |
11 MAY 2005 |
8 pages |
| Authors:
Michael D. Fayer; STANFORD UNIV CA DEPT OF CHEMISTRY
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| Infrared pump-probe experiments were used to study vibrational relaxation of polyatomic molecules in supercritical fluids and the gas phase. IR pump-probe experiments and theory were used to investigate hydrogen bond dynamics in oligomers of alcohols. Vibrational echo correlation spectroscopy (VECS) was developed and experiments were performed on molecules in liquids and gases. VECS is an ultrafast multidimensional approach that is in many respects the vibrational equivalent of multidimensional NMR. VECS ... |
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| Pulse Detonation Engine Thrust Tube Heat Exchanger for Flash Vaporization and Supercritical Heating of JP-8 |
MAR 2005 |
202 pages |
| Authors:
Christen L. Miser; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
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| Research has shown that performance of liquid hydrocarbon fueled pulse detonation engines is limited by the time required to evaporate liquid fuel droplets within the mixture. Vaporization of liquid fuels prior to injection has been shown to decrease ignition times and also increases fuel efficiency; however, the size and efficiency of the vaporization system used are not feasible for use in future pulse detonation aircraft concepts. The purpose of this ... |
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| Uniform Droplet Deposition of Thickened Chemical Agent Simulants By Supercritical Carbon Dioxide Viscosity Reduction |
16 NOV 2004 |
8 pages |
| Authors:
Michael V. Henley; Richard M. Weber; AIR FORCE RESEARCH LAB TYNDALL AFB FL
|
| Study of the fate of chemicals on substrates requires that those chemicals be applied to the substrate in a uniform and reproducible manner. Relatively simple means of droplet deposition of non-viscous chemicals are satisfactory, however thickened chemicals present problems using the same deposition techniques. By using supercritical carbon dioxide as a diluent, we were able to reduce the viscosity of various polymer-thickened chemicals and store them in a high-pressure reservoir. ... |
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| Liquid-Propellant Rocket Engine Injector Dynamics and Combustion Processes at Supercritical Conditions |
NOV 2004 |
251 pages |
| Authors:
Vigor Yang; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
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| The present AFOSR project focuses on the theoretical modeling and numerical simulation of liquid-propellant rocket engine injector flow and combustion dynamics. Emphasis is placed on cryogenic propellants in both shear and swirl co-axial injectors at supercritical conditions. The formulation is based on the full conservation equations in three dimensions, and accommodates variable properties and finite-rate chemical kinetics. Full account is taken of various high-pressure phenomena such as thermodynamic non- idealities ... |
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| Accurate Theoretical Prediction of the Properties of Energetic Materials |
31 AUG 2004 |
35 pages |
| Authors:
Donald L. Thompson; OKLAHOMA STATE UNIV STILLWATER DEPT OFCHEMISTRY
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| This report describes the progress and accomplishments for the period June 1, 2002 to August 31, 2004 for the MURI grant "Accurate Theoretical Predictions of the Properties of Energetic Materials" (no. DAAD19-02-1-0176). This is a multi-university, comprehensive theoretical/computational research program to develop, validate, benchmark, and apply methods and models that will provide predictive capabilities for energetic materials. The thrust of the work is the development of atomic-level models and ab ... |
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| Supercritical Carbon Dioxide Interaction with Polymeric Materials: Desorption Diffusion Coefficient Measurements |
JUL 2004 |
247 pages |
| Authors:
Wendel J. Shuely; Brian S. Ince; EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD RESEARCH AND TECHNOLOGY DIR
|
| Chemical-polymer compatibility is an important criterion in the development of solvent-based extraction and cleaning systems for removal of toxic contaminants from polymeric surfaces. The potential degradation of polymer properties and performance is especially critical for sensitive equipment cleaning, decontamination, and extraction. The candidate cleaning fluids for sensitive equipment include fluorinations and supercritical fluids. An overall material evaluation strategy has been developed for evaluating the degradation of polymer properties by exposure ... |
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| The Effects of Pressure and Acoustic Field on a Cryogenic Coaxial Jet |
16 DEC 2003 |
22 pages |
| Authors:
D. Davis; B. Chehroudi; ENGINEERING RESEARCH AND CONSULTING INC(ERC INC) EDWARDS AFB CA
|
| A coaxial injector was designed to inject liquid nitrogen (LN2) with a coflow of gaseous nitrogen (GN2) in its annular region as part of a program to better understand the nature of the interaction between acoustic waves and liquid the jets in cryogenic rocket engines. Backlit images were taken from the jets at various flow rates and at sub-, near-, and super-critical chamber pressures with and without the presence of ... |
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| Physical Methods For Inactivating Spores: A Critical Assessment |
19 NOV 2003 |
8 pages |
| Authors:
Glenn E. Spangler; Peter Setlow; Barbara Setlow; TECHNISPAN LLC PIKESVILLE MD
|
| A significant literature has developed around the application of physical techniques to the inactivation of spores. These include pulsed high electric fields, plasma sterilization, and supercritical fluid extraction, in addition to the more traditional autoclaving technique. Pulsed high electric fields electroporate protective membranes, plasma sterilizers generate very reactive species, and supercritical fluids extract biologically significant compounds. Not all these techniques work as described, however. The cortex interferes with electroporation by ... |
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| The Effect of Pressure and Acoustic Excitation on Coaxial LN2/GN2 Jets |
06 MAY 2003 |
4 pages |
| Authors:
D. Davis; B. Chehroudi; D. Talley; ENGINEERING RESEARCH AND CONSULTING INC(ERC INC) EDWARDS AFB CA
|
| The present trend in liquid rocket engines, gas turbines, and Diesel engines, is towards increasingly higher chamber pressures. In many cases, the chamber pressure can exceed the critical pressures of the fuel or oxidant Above the critical pressure, the distinction between the gas and liquid phases is lost, and mechanisms conventionally associated with subcritical spray combustion no longer necessarily apply. Until recently, relatively little has been understood about the injection ... |
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| Supercritical Fluid Spray Application Process for Adhesives and Primers |
01-Mar-2003 |
207 pages |
| Authors:
Marc D Donohue; JOHNS HOPKINS UNIV LAUREL MD
|
| In this project, we reformulated various solvent borne, high volatile organic compound (VOC) adhesives and adhesive primers, as cited in SERDP's Statement of Need, for application by a supercritical carbon dioxide spray process. Over the last several years, a new spray application process has been developed for polymeric based paints and other coatings that can reduce solvent VOC emissions up to 80%. This process was conceived by the principal investigator ... |
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| The California Coastal Jet: Synoptic Controls and Topographically Induced Mesoscale Structure |
MAR 2003 |
195 pages |
| Authors:
Patrick S. Cross; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF METEOROLOGY
|
| The low-level jet along the coast of southern Oregon and California is examined in detail through an extensive data set and the application of COAMPS, a mesoscale model, for the purpose of improving forecasts in challenging littoral environments. The jet forms within the broad equatorward flow established by the pressure gradient between cool ocean and warm land. The inception of the jet along the coast is about 250 km south ... |
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| Coaxial Injection under Supercritical Conditions |
JAN 2003 |
3 pages |
| Authors:
Bruce Chehroudi; Doug Talley; ENGINEERING RESEARCH AND CONSULTING INC(ERC INC) EDWARDS AFB CA
|
| This work reports on findings from the initial phase of a coaxial injection process under both subcritical and supercritical conditions. The results presented here are part of a systematic investigation of common rocket engine injectors, such as impinging and coaxial designs. Liquid nitrogen (LN2) is injected through a large length-to-diameter ratio circular hole and exposed at the exit to an annular jet of different gases including nitrogen, helium, and argon. ... |
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| Structure and Characterization of Sol-gel and Aerogel Materials and Oxidation Products from the Reaction of (CH3O)4Si and C16H33Si(OCH3)3 |
2003 |
6 pages |
| Authors:
Thomas M. Tillotson; John G. Reynolds; LAWRENCE LIVERMORE NATIONAL LAB CA CHEMISTRY AND MATERIALS SCIENCE DEPT
|
| Reactions of (CH3O)4Si and C16H33Si(OCH3)3 at various mole ratios were performed in methanol using base and acid catalysis. Sol-gel materials were formed that have low surface areas (approx. 10 sq m/g). Subsequent supercritical drying using CO2 at 40 deg. C produced materials that are very different than traditional aerogels, with surface areas around the same values as the corresponding sol-gels, as well as no detectable meso-pore features. In some cases ... |
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| A New Approach for Prediction of Aircraft Spin |
12 DEC 2002 |
53 pages |
| Authors:
Kyle D. Squires; ARIZONA STATE UNIV TEMPE DEPT OF MECHANICAL AND AEROSPACE ENGINEERING
|
| Unsteady Reynolds-averaged Navier-Stokes and Detached-Eddy Simulation are used to predict the flow around a forebody cross-section modeled by a rounded-corner square. The inlet velocity is inclined at 10 degrees to the main flow, the configuration modeling the massively separated flow around the forebody of a jet fighter rotating at high angle of attack. Simulations are performed at sub- and super-critical Reynolds numbers, corresponding to either laminar or turbulent boundary layer ... |
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| High Pressure and Supercritical Combustion: Interactions of Jets with Acoustic Waves |
AUG 2002 |
11 pages |
| Authors:
B. Chehroudi; D. G. Talley; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE WEST
|
| The objective of this task is to determine the mechanisms which control the breakup, transport, mixing, and combustion of high pressure and supercritical droplets, jets, and sprays, both as these pertain to steady' conditions as well as acoustically excited conditions. Previous results pertaining to 'steady' conditions have now been augmented with the initiation of a study of the interaction of subcritical and supercritical jets with acoustic waves. Preliminary results suggest ... |
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| Recent Developments in Liquid Rocket Injectors |
18 JUN 2002 |
61 pages |
| Authors:
Doug Talley; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
|
| These viewgraphs discuss rocket injectors, major trends since the end of the Cold War, recent developments in rocket injector design tools, gas/gas injector development, and injection at supercritical pressures. |
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| Preliminary Visualizations of Acoustic Waves Interacting with Subcritical and Supercritical Cryogenic Jets |
MAY 2002 |
7 pages |
| Authors:
Bruce Chehroudi; Doug Talley; ENGINEERING RESEARCH AND CONSULTING INC(ERC INC) EDWARDS AFB CA
|
| The effect of large amplitude acoustic waves on subcritical and supercritical cryogenic jets was studied. A general trend was observed that acoustic waves cause the time averaged cross section of the jet to flatten in a direction where the minor axis becomes aligned with the direction of propagation of the waves. It was also found that the presence of acoustic waves shortened the breakup length of the jets compared with ... |
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| The Fractal Geometry of Round Turbulent Cryogenic Nitrogen Jets at Supercritical Pressures |
MAR 2002 |
13 pages |
| Authors:
Bruce Chehroudi; Doug Talley; ENGINEERING RESEARCH AND CONSULTING INC(ERC INC) EDWARDS AFB CA
|
| Box-counting and EDM methods were used to measure the fractal dimension of round turbulent cryogenic nitrogen jets at pressures ranging from subcritical to supercritical pressures. Both method produced similar trends, with close quantitative agreement for a suitably small box-counting scale. At subcritical pressures, the fractal dimension was found to be consistent with the fractal dimension of a spray in the 2nd wind-induced atomization regime. The fractal dimension tended to increase ... |
|
| Army Research Office and Air Force Office of Scientific Research: 2002 Contractors Meeting in Chemical Propulsion |
2002 |
193 pages |
| Authors:
David M. Mann; Julian M. Tishkoff; ARMY RESEARCH OFFICE RESEARCH TRIANGLEPARK NC
|
| Abstracts are given for 6.1 basic research in chemical propulsion sponsored by the Army Research Office and the Air Force Office of Scientific Research. |
|
| Study of the Sub- and Supercritical Behavior of Fuel Droplets |
31 AUG 2001 |
57 pages |
| Authors:
Yaw D. Yeboah; CLARK ATLANTA UNIV GA
|
| A study of the droplet gasification and combustion characteristics of hydrocarbon fuel droplets was conducted at sub- and supercritical. The experimental setup provided quiescent and convective environments under supercritical pressure and temperature conditions. The droplet combustion experiment hardware consisted of: a liquid pressurizing and transfer system; a high pressure and temperature combustion chamber; a droplet formation, deployment and ignition system; and a high speed CCD imaging system. The gasification and ... |
|
| Electrochemical Properties of High Surface Area Vanadium Oxide Aerogels |
25 JUN 2001 |
16 pages |
| Authors:
Winny Dong; Debra R. Rolison; Bruce Dunn; CALIFORNIA UNIV LOS ANGELES DEPT OF MATERIALS SCIENCE AND ENGINEERING
|
| This article explores the effects of surface area and pore volume on the electrochemical behavior of high surface area V2O5 gels dried by either supercritical or ambient methods. Traditional composite electrode structures have prevented truly quantitative analysis of surface area effects in nanoscale battery materials, as well as a study of their innate electrochemical behavior. These limitations can be overcome by using the sticky-carbon' electrode technique, which provides a direct ... |
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| AFOSR Sponsored Research in Combustion and Diagnostics |
19 JUN 2001 |
|
| Authors:
Julian M. Tishkoff; AIR FORCE OFFICE OF SCIENTIFIC RESEARCH ARLINGTON VA
|
| The Air Force Office of Scientific Research (AFOSR) program in combustion and diagnostics currently is focused on five areas of study: high-speed propulsion, turbulent combustion, atomization and sprays, diagnostics, and supercritical fuel behavior. An assessment of major research needs in each of these areas is presented. |
|
| Kinetics of Supercritical Water Oxidation-SERDP Compliance Technical Thrust Area |
JUN 2001 |
162 pages |
| Authors:
Steven F. Rice; SANDIA NATIONAL LABS ALBUQUERQUE NM
|
| This final report has two purposes. The first is to provide a single document that contains a description of this project's goals, activities, and accomplishments over the 8 year period of performance from January, 1993 to August, 2000. The second purpose is to provide an overview of the technical results that have been obtained and to submit a roadmap that identifies the publications and reports where the details of these ... |
|
| ARO and AFOSR 2001 Contractors' Meeting in Chemical Propulsion |
JUN 2001 |
185 pages |
| Authors:
David M. Mann; Julian M. Tishkoff; ARMY RESEARCH OFFICE RESEARCH TRIANGLEPARK NC
|
| Abstracts are given for 6.1 basic research in chemical propulsion sponsored by the Army Research Office and the Air Force Office of Scientific Research. |
|
| Liquid-Propellant Droplet Combustion and Cluster-Behavior at Supercritical Conditions |
MAY 2001 |
214 pages |
| Authors:
Yigor Yang; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL ENGINEERING
|
| A systematic investigation of superoritical droplet vaporization and cluster behavior has been conducted based on the complete conservation equations in both the gas and liquid phases. The research work addresses a variety of fundamental issues related to droplet vaporization and dynamics at realistic conditions typical of liquid-propellant rocket combustion devices. A unified treatment of real-fluid thermodynamics has been developed based on fundamental theories. Special attention was given to the thermodynamic ... |
|
| Thermodynamic and Modeling Study of Selected Aqueous Chemical Systems from 370 to 450 Degrees Celcius |
30 MAR 2001 |
7 pages |
| Authors:
Reed M. Izatt; John L. Oscarson; BRIGHAM YOUNG UNIV PROVO UT
|
| Determination of thermodynamic quantities (K, DELTA H deg, DELTA S deg, and DELTA C sub p deg) for chemical reactions in the supercritical water region has special requirements. During the grant period, progress has been made in meeting these requirements in several areas. First, a new calorimeter has been constructed that overcomes significant experimental challenges in this temperature region. In this calorimeter, the reaction vessel and associated tubing are immersed ... |
|
| The RCM1 - A Test Case. A First Attempt to Model a Supercritical Cryogenic Injection Using the CPS Code |
MAR 2001 |
18 pages |
| Authors:
BERTIN TECHNOLOGIES ST QUENTIN EN YVELINES (FRANCE)
|
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| The Behavior of Cryogenic Shear Layers Under Supercritical Conditions |
MAR 2001 |
8 pages |
| Authors:
B. Chehroudi; R. Cohn; D. Talley; ENGINEERING RESEARCH AND CONSULTING INCEDWARDS AFB CA
|
| Recent experience gained at AFRL with the injection of cryogenic fluids into high back-pressures is summarized. In the experimental investigations described, a jet of a cryogenic fluid, typically liquid N2, is injected into a chamber whose ambient pressure is varied to values exceeding the critical pressure of the injectant. The structure of the jet and the shear layer between the jet and the ambient has been examined. Results from visualization, ... |
|
| Fuels Combustion Research: Supercritical Fuel Pyrolysis |
22 JAN 2001 |
41 pages |
| Authors:
Irvin Glassman; PRINCETON UNIV NJ DEPT OF MECHANICAL AND AEROSPACE ENGINEERING
|
| Present and anticipated variation in jet propulsion fuels due to advanced engine compression ratios and airframe cooling requirements necessitate greater understanding of chemical phenomena associated with the feed system and combustion aspects of the airbreathing propulsion systems under consideration by the U. S. Air Force. With AFOSR support an integrated. fundamental research program had been established at Princeton. The focus during the subject period was directed to understanding the pyrolysis ... |
|
| Controlling Zebra Mussels, Quagga Mussels, and Biofilm Growth with the Plasma Sparker |
DEC 2000 |
3 pages |
| Authors:
ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENGINEER RESEARCH AND DEVELOPMENT CENTER
|
| A plasma sparker has been developed by Sparktec Environmental, Inc., to control zebra mussels (Dreissenapolymorpha) and quagga mussels (Dreissena bugensis). The device produces aplasma pulse, which is a physical, nonchemical, nonthermal process that introduces energy directly into an aqueous solution. When the plasma sparker is activated, electrical energy stored by capacitors is released in microseconds between two submersed electrodes. A plasma channel is formed because of this high current/high voltage ... |
|
| Fuels Combustion Research: Supercritical Fuel Pyrolysis |
21 SEP 2000 |
39 pages |
| Authors:
Irvin Glassman; PRINCETON UNIV NJ DEPT OF MECHANICAL AND AEROSPACE ENGINEERING
|
| Present and anticipated variation in jet propulsion fuels due to advanced engine compression ratios and airframe cooling requirements necessitate greater understanding of chemical phenomena associated with the feed system and combustion aspects of the airbreathing propulsion systems under consideration by the U.S. Air Force. With AFOSR support an integrated, fundamental research program had been established at Princeton. The focus during the subject period was directed to ... |
|
| Sedimentation Study and Flume Investigation, Mission Creek, Santa Barbara, California; Corte Madera Creek, Marin County, California |
APR 2000 |
111 pages |
| Authors:
Ronald R. Copeland; Darla C. McVan; Scott E. Stonestreet; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS COASTAL AND HYDRAULICS LAB
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| A concrete-lined supercritical-flow flood-control channel was designed for Mission Creek in Santa Barbara, California. The design did not include a debris basin at the upstream end of the channel, so there was potential for a significant quantity of bed load to be delivered during a flood event. An existing concrete-lined flood control channel on Corte Madera Creek in Marin County, California lacks a debris basin at ... |
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| Development of High Performance Polymer Fibers Using Subcritical and Supercritical CO2 |
01 MAR 2000 |
6 pages |
| Authors:
Alan J. Lesser; MASSACHUSETTS UNIV AMHERST DEPT OF POLYMER SCIENCE AND ENGINEERING
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| Enhancements in ballistic protective wear for soldiers rely heavily on the development of lightweight materials with increased moduli and strength. It is well established that an armors ballistic limit can be increased significantly by using materials with increased moduli and strength. The development of high performance fibers from flexible chain polymers has been a subject of intense interest over the past 30 years. However, to ... |
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SUPERCRITICAL FLOW
