| Velocity Selection of Fast Laser Ablated Metal Atoms by a Novel Nonmechanical Technique: Temporally and Spatially Specific Photoionization (TASSPI) |
FEB 1998 |
71 pages |
| Authors:
Mario E. Fajardo; PHILLIPS LAB EDWARDS AFB CA
|
 | This report documents the in-house research effort that led to the development of a novel, nonmechanical technique for performing velocity selection of fast laser ablated atoms. The technique is named "TASSPI" for Temporally and Spatially Specific Photo-Ionization as ablated metal atoms moving either too slowly or too quickly to be hidden behind an opaque mask are photoionized by a second pulsed laser and then deflected from the main atomic beam ... |
|
| Functionalized Polyhedral Oligosilsesquioxane (POSS) Macromers: New Graftable POSS-Hydride, POSS-Alpha-Olefin, POSS-Epoxy, and POSS-Chlorosilane Macromers and POSS-Siloxane Triblocks |
07 DEC 1997 |
34 pages |
| Authors:
Edward G. Shockey; Alan G. Bolf; Paul F. Jones; Joseph J. Schwab; Kevin P. Chaffee; PHILLIPS LAB EDWARDS AFB CA
|
| A series of polyhedral oligomeric silsesquioxanes (POSS) monomers bearing silane or alpha-olefin substituents have been prepared and their chemistry explored. Both the POSS silanes and alpha-olefin monomers readily participate in hydrosilation chemistry and have been used as starting materials for the preparation of POSS sol-gel type reagents. Similarly, POSS silanes and alpha-olefins are reactive towards silane and olefin functionalized polymers which makes them useful as grafting reagents. The utility of ... |
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| The Electric Propulsion Space Experiment (ESEX) - A Demonstration of High Power Arcjets for Orbit Transfer Applications |
03 NOV 1997 |
7 pages |
| Authors:
D. R. Bromaghim; R. M. Salasovich; J. R. LeDuc; L. K. Johnson; PHILLIPS LAB EDWARDS AFB CA
|
| The Electric Propulsion Space Experiment (ESEX) is a high power (30 kW) ammonia arcjet space demonstration sponsored by the Propulsion Directorate of the Phillips Laboratory with TRW as the prime contractor. ESEX is one of nine experiments being launched in early 1998 on board the Advanced Research and Global Observation Satellite (ARGOS). ESEX will demonstrate the feasibility of using a high power arcjet for orbit transfer. ESEX is instrumented with ... |
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| Application of Genetic Algorithms to In Situ Particle Sizing |
JUL 97 |
50 pages |
| Authors:
Michael R. McKee; PHILLIPS LAB EDWARDS AFB CA
|
| Particulates in the solid rocket exhaust plume cause rocket base heating, motor performance losses, and determine the plume spectral properties. The particle properties that contribute to these effects are the particle size distribution function (PSDF), emissivity, density, and surface tension. Of the four, the PSDF and emissivity are not very well known. Until an adequate model is developed for the PSDF and emissivity, in situ measurements will have to be ... |
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| Solar Plasma Physics |
MAR 97 |
8 pages |
| Authors:
C. W. Larson; PHILLIPS LAB EDWARDS AFB CA
|
| This final report provides a historical perspective and a summary of the productivity of this project. Twenty-one publications were produced during the 10-year period 1986 to 1996 as conference proceedings, technical reports, Ph.D dissertations and referred papers. The objective of the project was to measure the optical absorptivities in the visible region of the spectrum of alkali metal vapors in hydrogen gas to support the design of a solar powered ... |
|
| Proceedings of the High Energy Density Matter (HEDM) Contractors |
MAR 97 |
|
| Authors:
Patrick G. Carrick; Neal T. Williams; PHILLIPS LAB EDWARDS AFB CA
|
 | This report documents the information presented at the tenth annual High Energy Density Matter (HEDM) Contractors' Conference held 5-7 June 1996 in Boulder CO. This report contains the extended abstracts of the oral, workshop, and poster presentations given by the Air Force funded contractors and by the in-house researchers from the Phillips Laboratory. |
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| Cumulative Damage and Crack Growth in Solid Propellant. Phase I |
FEB 97 |
31 pages |
| Authors:
C. T. Liu; PHILLIPS LAB EDWARDS AFB CA
|
| This report covers results of research addressing the fracture and crack growth behavior of solid propellants in support of structural integrity methodology for the failure response of solid propellant rocket motors. The effects of damage, temperature, and strain rate on local behavior near the crack tip and crack growth behavior in solid propellants were investigated. Numerical modeling techniques were used to determine the local strain fields near the crack tip ... |
|
| Microtube and Composites Research |
DEC 96 |
38 pages |
| Authors:
W. Hoffman; P. B. Pollock; PHILLIPS LAB EDWARDS AFB CA
|
| This technical report covers research on the properties and behavior of micron-sized tubes. The tubes in this study were made of glass, nickel, copper and silver. Diameters were in the range of 10-100 micrometers. Flow studies were conducted to examine the applicability of classical fluid mechanics to this flow regime. Water was flowed through the tubes, and the flow rate was measured over long periods of time. The results show ... |
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| Phillips Laboratory Solar Thermal Propulsion Efforts |
DEC 96 |
|
| Authors:
Joel A. Sisk; Andrea Jensen; PHILLIPS LAB EDWARDS AFB CA
|
| Solar thermal propulsion is a highly efficient, economical, and innovative alternative to current chemical orbit transfer propulsion systems. The Propulsion Directorate of Phillips Laboratory has been aware of the potential for this type of propulsive system for over 30 years. Throughout those years, the concept was revisited numerous times, in the form of basic concept verification and feasibility studies, until finally, a solar thermal propulsion test facility was established in ... |
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| Particulate Emission from a Pulsed Plasma Thruster |
DEC 96 |
|
| Authors:
Gregory G. Spanjers; Jason S. Lopspeich; Keith A. McFall; Ronald A. Spores; PHILLIPS LAB EDWARDS AFB CA
|
| Propellant inefficiency resulting from the ejection of propellant material in particulate form is characterized in a Pulsed Plasma Thruster (PPT). Exhaust deposits are collected and analyzed using a combination of Scanning Electron Microscope (SEM), Energy Dispersive X-ray Analysis (EDAX), and microscopic imaging. Teflon particulates are observed with sizes ranging from over 100 microns down to less than 1 microns. Estimates of the mass entrained in this form show that the ... |
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| Flight Diagnostics and Integrated Vehicle Testing of the U.S. Air Force Electric Propulsion Space Experiment (ESEX) |
DEC 96 |
|
| Authors:
R. M. Salasovich; J. R. LeDuc; L. K. Johnson; D. R. Bromaghim; PHILLIPS LAB EDWARDS AFB CA
|
| The Electric Propulsion Space Experiment (ESEX) comprises a 30 kW ammonia arcjet system, onboard diagnostics, and remote observations program. A scientific plan encompassing implementation, operation, and data analysis has been developed. Onboard instruments will provide accurate measurements of spacecraft acceleration, thruster operating characteristics, and radiated thermal loads, and will document arcjet operation through filtered imagery. Instruments will also provide upper limits for spacecraft contamination and communications band electromagnetic interference. The ... |
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| Application of Automated NDE Data Evaluation to Missile and Aircraft Systems |
DEC 96 |
13 pages |
| Authors:
Joseph H. Hildreth; PHILLIPS LAB EDWARDS AFB CA
|
| As part of the Advanced Launch System technology development effort begun in 1989, the Air Force initialized a program to automate, to the extent possible, the processing of NDE of NDE data from the inspection of solid rocket motors during fabrication. The computerized system, called the Automated NDE data Evaluation System or ANDES, was developed under contract to Martin Marietta. The generic ANDES system has been tailored to support inspection ... |
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| Computer Aided Feature Extraction, Classification and Acceptance Processing of Digital NDE Data |
DEC 96 |
13 pages |
| Authors:
Joseph H. Hildreth; PHILLIPS LAB EDWARDS AFB CA
|
| As part of the Advanced Launch System technology development effort begun in 1989, the Air Force initialized a program to automate, to the extent possible, the processing of NDE of NDE data from the inspection of solid rocket motors during fabrication. The computerized system, called the Automated NDE data Evaluation System or ANDES, was developed under contract to Martin Marietta, now Lockheed Martin. The ANDES system is generic in structure ... |
|
| Surface Science for Advanced Propulsion |
AUG 96 |
313 pages |
| Authors:
Kevin P. Chaffee; John J. Rusek; PHILLIPS LAB EDWARDS AFB CA
|
| Complex composite structures are prevalent throughout the propulsion industry. Unavoidable are the many interfaces between materials of differing physical and chemical properties. In applications where nut-and-bolt fasteners are not appropriate, the 'adhesive' quality of the interface becomes a serious consideration with regard to overall system integrity and reliability. Indeed, it is the ability of the structure to transfer or distribute stress when subjected to, for example, thermal and mechanical loading, ... |
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| The Digital Valve and Liquid Hydrogen Hydrostatic Bearings |
JUL 1996 |
9 pages |
| Authors:
Michael K. Rokaw; Adam P. Getchell; PHILLIPS LAB EDWARDS AFB CA
|
| Phillips Laboratory and its industrial partners have invested considerable resources into the development of hydrostatic bearings and their applications to turbopump technologies. The hydrostatic bearing has a thin film of high pressure fluid as a layer between the turbopump shaft ad the hydrostatic bearing. This concept decreases the weight and increases the lifetime of the turbopump by eliminating friction between bearing surfaces. The liquid hydrogen hydrostatic bearing program at the ... |
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| Structural/Ballistic Instability Ageout Mechanism in the Sparrow Mark 52 SRM |
MAY 1996 |
8 pages |
| Authors:
D. I. Thrasher; P. R. Empleo; PHILLIPS LAB EDWARDS AFB CA
|
| A three dimensional finite element analysis and a one dimensional incompressible flow model were used to investigate the interaction between the internal ballistics and the structural grain deformations for the Sparrow Mark 52 rocket motor. The results confirm earlier investigators' conclusions (based on two dimensional structural analysis) that a mechanism exists for pressure spiking driven by choking of the gas flow within the bore cavity due to grain structural deformations. ... |
|
| Hybrid Propulsion for Air Force Applications Study |
MAY 96 |
71 pages |
| Authors:
Kevin E. Mahaffy; George C. Harting; Ronald Bates; Ray Walsh; Craig Hansen; PHILLIPS LAB EDWARDS AFB CA
|
| The Hybrid Propulsion for Air Force Applications Study was performed by the Air Force Phillips Laboratory at Edwards Air Force Base, California. The hybrid propulsion study's four main objectives were (1) to conduct a survey of the current state-of-the-art technology in hybrid propulsion, (2) to determine if there is a payoff for using hybrid propulsion in Air Force missions, (3) to make recommendations as to whether or not hybrid pro- ... |
|
| Proceedings of the High Energy Density Matter (HEDM) Contractors' Conference held in Woods Hole, Massachusetts on 4-7 June 1995 |
JAN 96 |
376 pages |
| Authors:
Patrick G. Carrick; Simon Tam; PHILLIPS LAB EDWARDS AFB CA
|
| This report documents the information presented at the ninth annual High Energy Density Matter (HEDM) Contractors' Conference held 4-7 June 1994 in Woods Hole, MA. This report contains the extended abstracts of the oral, workshop, and poster presentations given by the Air Force funded contractors and by the in house researchers from the Phillips Laboratory. |
|
| Solar Thermal Propulsion Experiments Design |
1996 |
13 pages |
| Authors:
Kristi K. Laug; PHILLIPS LAB EDWARDS AFB CA
|
| Satellites that are currently under powered or have low photovoltaic (PV) efficiency, may be rejuvenated by dosing them with laser power beamed from earth. Also, current strictly solar thermal propulsion schemes may be able to use laser power as a replacement energy source when they are eclipsed. Several questions must be answered before a multiple use of laser power may be designated. The questions are outlined in the background section ... |
|
| Characterization of Cryogenic Solid Hybrid Rocket Motors |
DEC 95 |
|
| Authors:
Patrick G. Carrick; C. W. Larson; Kevin L. Pfeil; PHILLIPS LAB EDWARDS AFB CA
|
| The study of the combustion of cryogenic (77K) solid hydrocarbons in a laboratory scale tube burner that approximates the geometry of the hybrid rocket was extended. This work was carried out to demonstrate the feasibility of cryogenic fuel combustion in the hybrid rocket geometry and to extend knowledge about hybrid rockets to fuels that have very high regression rates as a consequence of their high mass transfer number, or blowing ... |
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| Hydrogen Peroxide for Rocket Propulsion Applications |
DEC 95 |
16 pages |
| Authors:
John J. Rusek; PHILLIPS LAB EDWARDS AFB CA
|
| Traditionally, macroscopic metallic and ceramic screens have been used as catalysts for the controlled decomposition of hydrogen peroxide as applied to monopropellant thrusters, liquid rocket engines, and hybrid rocket systems. Catalyst activity depends on available catalytic surface area; metallic catalyst stability is generally degraded by catalyst oxidation. This paper will discuss new approaches to forming inexpensive, high surface area decomposition catalyst packs for flightweight applications. The paper will specifically discuss ... |
|
| Advanced Polymer Components. Volume 2 |
OCT 95 |
201 pages |
| Authors:
John Rusek; PHILLIPS LAB EDWARDS AFB CA
|
| The Advanced Polymer Components Initiative began in December l989. The initial purpose of the program was to explore advanced engineering polymers for use as rocket propulsion components. As research progressed it became apparent that advanced thermoplastics in general were highly dependent on processing and post-processing as well as on chemical composition and morphology. This realization led to a branching of the original objective into an applications research goal and a ... |
|
| Advanced Polymer Components. Volume 1 |
OCT 95 |
239 pages |
| Authors:
John Rusek; PHILLIPS LAB EDWARDS AFB CA
|
| The Advanced Polymer Components initiative began in December 1989. The initial purpose of the program was to explore advanced engineering polymers for use as rocket propulsion components. As research progressed it became apparent that advanced thermoplastics in general were highly dependent on processing and post-processing as well as on chemical composition and morphology. This realization led to a branching of the original objective into an applications research goal and a ... |
|
| Monte Carlo Simulations of the Structures and Optical Absorption Spectra of Na Atoms in Ar Clusters, Surfaces, and Solids; a Detailed Presentation of the Theoretical Methods Used |
JUN 95 |
60 pages |
| Authors:
Jerry A. Boatz; Mario E. Fajardo; PHILLIPS LAB EDWARDS AFB CA
|
| Optical absorption spectra of Na/Ar systems are calculated by combining the classical Monte Carlo simulation method with a quantum mechanical first-order perturbation scheme for estimating the energies of the Na (3p(2P)) excited states. The model incorporates many drastic approximations, but contains no adjustable parameters. Our Na/Ar matrix simulations generated relaxed structures for several candidate trapping sites based on various sized vacancies in fcc solid Ar. Trapping sites for which the ... |
|
| Dependence of Solar-Thermal Rocket Performance on Concentrator Performance |
1995 |
14 pages |
| Authors:
Michael R. Holmes; Kristi K. Laug; PHILLIPS LAB EDWARDS AFB CA
|
| The Phillips Laboratory (OLAC) at Edwards Air Force Base is actively working to forward research and development in Solar-Thermal Propulsion. The concentrator support structure trade studies reviewed were the result of PRDA program Research and Development Announcement) contracts, for example. Recent funding is through SBIR (Small Business Innovative Research), however, as money for larger contracts becomes rare. Topics such as space concentrator development, thruster development, pointing and accuracy, etc. are ... |
|
| Theoretical Absorption Spectroscopy of High-Temperature Metal Vapors: Model and Experiment Compared |
DEC 94 |
36 pages |
| Authors:
Jeffrey D. Mills; PHILLIPS LAB EDWARDS AFB CA
|
| Theoretical calculations in support of absorption spectroscopy of buffered metallic vapors in the Plasma Spectroscopy Cell are described. After a brief exposition of the theoretical principles and ingredients of the quantum- mechanical, state-to-state treatment of transition processes in atoms and diatoms at thermodynamic equilibrium, various aspects of the model and experimental absorption spectra for the lithium system are compared and discussed. Special emphasis is given to outlining those spectral characteristics ... |
|
| Proceedings of the High Energy Density Matter (HEDM) Contractor's Conference held 5-7 June 1994 in Crystal Bay Neveda |
DEC 94 |
308 pages |
| Authors:
T. L. Thompson; S. L. Rogers; PHILLIPS LAB EDWARDS AFB CA
|
| This report documents the information presented at the eighth annual High Energy Density Matter (HEDM) Contractors' Conference held 5-7 June 1994 in Crystal Bay NV. This report contains the extended abstracts of the oral, workshop, and poster presentations given by the Air Force funded contractors and by the in-house researchers from the Phillips Laboratory. The main purpose of the High Energy Density Matter (HEDM) program is to research and develop ... |
|
| High Temperature Spectroscopy of Alkali Metal Vapors for Solar to Thermal Energy Conversion |
NOV 94 |
13 pages |
| Authors:
Paul S. Erdman; William C. Stwalley; PHILLIPS LAB EDWARDS AFB CA
|
| Solar Plasma propulsion methods proposed by the Air Force have lead to the study of high temperature optical absorption of metal vapors. The Plasma Spectroscopy Cell in the Phillips Laboratory at Edwards AFB CA has been used to obtain an abundance of absorption spectra at temperatures approaching 2000 K and pressures of one atmosphere for lithium and sodium metal vapors. Tentative assignments of molecular transitions are improved upon by use ... |
|
| Explosive Testing of Class 1.3 Rocket Booster Propellant |
Aug 1994 |
39 pages |
| Authors:
Claude Merrill; Albert Nichols; Edward Lee; PHILLIPS LAB EDWARDS AFB CA
|
| Recent experimentation has provided a more thorough understanding of the explosive response of class 1.3 composite propellant to severe impact. This study looked at an 88 % total solids HTPB/Al/AP propellant similar to what could be used in space launch boosters. The program tested propellant charges as large as 22 inches in diameter. It includes hydrodynamic modeling for developing a basic understanding of the mechanisms and to develop reliable methods ... |
|
| Kinetic Deuterium Isotope Effects in the Combustion of Formulated Nitramine Propellants |
1994 |
17 pages |
| Authors:
Paul C. Trulove; Robert D. Chapman; Scott A. Shackelford; PHILLIPS LAB EDWARDS AFB CA
|
| The kinetic deuterium isotope effect was used to investigate the rate-limiting process in the combustion of formulated nitramine propellants. Model Propellant formulations containing either octahydro-1,3,5,7-tetranitro-1, 3,5,7-tetrazocine (HMX), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), or their deuteriated analogues were pressed into pellets and burned under nitrogen pressure in a window bomb. The magnitudes of the observed deuterium isotope effects indicate that the HMX and RDX exert significant control over the combustion phenomenon of the propellants ... |
|
| The Contribution of Matrix Plasticity to the Frictional Sliding of Debonded Fibers in Sapphire-Reinforced TiAl Matrix Composites. |
1994 |
|
| Authors:
J. M. Galbraith; D. A. Koss; J. R. Hellmann; PHILLIPS LAB EDWARDS AFB CA
|
| Large-scale fiber displacement behavior, usually characterized by a "frictional" sliding stress (t slide), has been studied in two sapphire-reinforced tial systems. experimental results from fiber push-out and reverse push-back tests indicate that the large-scale sliding behavior of debonded fibers leads to an average t slide -value which progressively decreases during fiber displacements. previous studies of scs-6 (sic) fiber-reinforced glass and metal matrix composites have attributed decreases in t slide to ... |
|
| Bonding Aluminum Flanges to Composite Tubes for Space Applications. |
1994 |
|
| Authors:
Clifford F. Shaeffer; Jay M. Galbraith; James A. Harvey; PHILLIPS LAB EDWARDS AFB CA
|
|
| Proceedings of the High Energy Density Matter (HEDM) Contractor's Conference Held in Woods Hole, Massachusetts on 6-8 June 1993 |
NOV 93 |
466 pages |
| Authors:
T. L. Thompson; PHILLIPS LAB EDWARDS AFB CA
|
| This report documents the information presented at the seventh annual High Energy Density Matter (HEDM) Contractors Conference held 6 - 8 June 1993 in Woods Hole, MA. This report contains the extended abstracts of the oral, workshop and poster presentations given by the Air Force funded contractors and by the in-house researchers from the Phillips Laboratory. HIDM, High energy density matter, Propellant, Solid hydrogen, Cryogenic matrices, Energetic materials, Potential energy ... |
|
| Foam Inflated Rigidized Structures for Space Applications |
NOV 1993 |
10 pages |
| Authors:
D. M. Lester; M. J. Warner; M. Blair; PHILLIPS LAB EDWARDS AFB CA
|
| Large lightweight stowable structures that can be deployed in space without astronauts having to perform extra-vehicular activities are vital to expanding space exploration and use. To meet this challenge, Foam Inflated Rigidized (FIR) structures have been developed by Thiokol Corporation as part of the Air Force's Gossamer Baggie Torus program. These beam-like structures are intended to stabilize the solar collector of a solar thermal rocket. This paper discusses the design, ... |
|
| One Dimensional Model of a Solar-Thermal Thruster Using a Porous Absorber/Heat Exchanger |
15 OCT 1993 |
30 pages |
| Authors:
Michael R. Holmes; PHILLIPS LAB EDWARDS AFB CA
|
| This paper presents a one dimensional model of a solar-thermal thruster using a porous disk as a concentrated sunlight absorber and heat exchanger. This type of thruster is one of several high Isp thruster concepts being studied by the Phillips Laboratory to transfer payloads from low earth orbit to geosynchronous orbit. Soar propulsive techniques should deliver close to 1000 sec of Isp using a very low molecular weight propellant,hydrogen. The ... |
|
| An Investigation of the Breakdown Voltage Characteristics of a 30 kW class Ammonia Arcjet |
SEP 1993 |
17 pages |
| Authors:
PHILLIPS LAB EDWARDS AFB CA
|
| The primary objective of this work was to identify methods to reduce the mean dynamic breakdown voltage (MDBV) of the ammonia propellant in the ESEX 26 kW arcjet. The approach to this objective was to establish a test matrix to investigate the influence of mass flow rate, electrode gap distance, cathode tip shape, and voltage ramp rate on the MDBV. Only the mass flow rate and voltage ramp rate were ... |
|
| An Overview of the Air Force's Electric Propulsion Program |
SEP 1993 |
8 pages |
| Authors:
David R. Perkins; PHILLIPS LAB EDWARDS AFB CA
|
| This paper discusses the electric propulsion technology development efforts being pursued by the United States Air Force. Discussion is provided on the electric propulsion efforts of Phillips Laboratory's Propulsion Directorate in basic research, exploratory development, as well as the Advanced Technology Transition Development effort that will result in a space flight experiment of a 26 kilo-watt arcjet. Also discussed is Phillips Laboratory's ELITE/SSTAR program and a brief discussion of the ... |
|
| Overview of the Air Force ESEX Flight Experiment |
AUG 1993 |
8 pages |
| Authors:
A. M. Sutton; PHILLIPS LAB EDWARDS AFB CA
|
| In the post cold war, the United States Air Force is challenged by the need for increased maneuverability of the U.S. space assets, and the need to reduce launch costs. These needs have spawned the Electric Propulsion Space Experiment (ESEX). ESEX will address key issues associated with high power arcjets. Measuring performance in space and interactions on the spacecraft of this new plasma propulsion system will provide the first step ... |
|
| Investigating Cumulative Damage in a Highly Filled Polymeric Composite Material |
JUL 1993 |
15 pages |
| Authors:
C. T. Liu; B. Tang; PHILLIPS LAB EDWARDS AFB CA
|
| The effects of cyclic loading on cumulative damage, constitutive behavior, and residual strength of a highly filled polymeric composite material were investigated in this study. Uniaxial tensile specimens were used to study the accumulation of damage in the material subjected to different cyclic loading sequences. Loads, displacements, and ultra- sonic measurements made by transmitting sound waves through the thickness of the specimens were recorded during the tests. The recorded data ... |
|
| Catalog of Absolutely Calibrated, Range Normalized, Wideband, Electric Field Waveforms from Triggered Lightning Flashes in Florida |
22 JUN 93 |
106 pages |
| Authors:
Yataka Izumi; John C. Willett; PHILLIPS LAB EDWARDS AFB CA
|
| During the summer of 1987, a rocket-triggered-lightning program was conducted at the NASA Kennedy Space Center, Florida. The rocket triggering was performed from two trigger platforms - one over water and the other over land. The propagation paths from the two sites were almost entirely over brackish water. This report presents waveform plots of the electric-field time derivative, the electric field, and the high-frequency spectral density at 5 MHz. ... |
|
| Catalog of Absolutely Calibrated, Range Normalized, Wideband, Electric Field Waveforms from Triggered Lightning Flashes in Florida. |
22 JUN 1993 |
|
| Authors:
Yataka Izumi; John C. Willett; PHILLIPS LAB EDWARDS AFB CA
|
| During the summer of 1987, a rocket-triggered-lightning program was conducted at the NASA Kennedy Space Center, Florida. The rocket triggering was performed from two trigger platforms - one over water and the other over land. The propagation paths from the two sites were almost entirely over brackish water. This report presents waveform plots of the electric-field time derivative, the electric field, and the high-frequency spectral density at 5 MHz. |
|
| Process Relationship as Influenced by Carbonization Rate |
JUN 93 |
5 pages |
| Authors:
Kristen M. Kliner; David P. Anderson; Timothy D. Naughton; PHILLIPS LAB EDWARDS AFB CA
|
| The typical process cycle for a carbon-carbon composite begins with an organic matrix impregnated fibrous preform cured according to conventional composite practices (e.g., lay-up, bagging and autoclave cure; hot pressing; etc.). This cured composite is then subjected to a pyrolysis cycle in the absence of oxygen which results in the carbonization of the matrix. Carbonization cycles are carried out to temperatures of 650-800 deg C for several hours or even ... |
|
| Specific Impulse Calculations of High Energy Density Solid Cryogenic Rocket Propellants. 1. Atoms in Solid H2 |
APR 93 |
63 pages |
| Authors:
Patrick G. Carrick; PHILLIPS LAB EDWARDS AFB CA
|
| Specific impulse calculations for a wide range of input concentrations are reported for atomic additives to solid hydrogen, combusted with liquid oxygen. These specific impulse values are presented in the form of 3D contour plots that reveal information about an entire region of interest. The output product species are also presented in this manner. These plots can be used to determine the optimum performance of any particular additive concentration and ... |
|
| Freon Recovery from Nitrogen Tetroxide and Freon Solutions |
APR 93 |
34 pages |
| Authors:
Robert O. Bucsh; PHILLIPS LAB EDWARDS AFB CA
|
| A reactor was designed, built, and tested to extract N2O4 from a N2O4 in Freon solution. A two step chemistry process was developed, the N2O4 is extracted from the Freon as KNO2 and KNO3 with aqueous KOH. The KNO2 is converted to N2 and K2SO4 by sulfamic acid. The excess KOH is neutralized with nitric acid to produce an innocuous KNO3 solution. The concentration of N2O4 left in the treated ... |
|
| Application of the Saha Equation to High Temperature (> or = 6000K) rocket Exhaust |
MAR 93 |
164 pages |
| Authors:
Robert T. Nachtrieb; PHILLIPS LAB EDWARDS AFB CA
|
| Using the SAHA equations and spectroscopic constants, the computer program in this report calculates the species populations of diatomic molecules, neutrals, ions, and electrons in a plasma. The code considers the equilibrium of a two-elements, chemically reacting plasma, by calculating the partition function for each species. By rederiving theoretically, as the JANNAF tables do, the thermodynamic properties of a rocket propellant, but using extended excitation levels, the program can estimate ... |
|
| Studies of Hafnium-Carbide Wafers Using a Thermogravimetric Analyzer |
1993 |
12 pages |
| Authors:
Domingo G. Castillo; Paul F. Jones; PHILLIPS LAB EDWARDS AFB CA
|
| Solar thermal propulsion can improve orbital transfer and maneuvering of space payloads due to double the performance of specific impulse (lsp) over chemical propulsion systems. Solar thermal can accomplish this increased performance by absorbing concentrated solar energy with very high temperature materials which through conduction heat hydrogen (H2). Hafnium carbide (HfC) is an excellent candidate material as a solar absorber and conductor because of its high melting temperature of 395000 ... |
|
| The Universal Applications of Microtubes and Microtube Composites. |
1993 |
|
| Authors:
Wesley P. Hoffman; Kamleshwar Upadhya; PHILLIPS LAB EDWARDS AFB CA
|
| This paper concerned mmc in some important way and contained information about, utilized, or discussed these subjects: basic topics:, composite materials materials and material types:, microtubes material characteristics and data fields:, cost data, manifolding interfaces, porosity testing and test conditions:, high temperature effects, sem manufacturing:, fatigue tube forming miscellaneous and special technical terms:, afosr, aspect ratios, insulation applications, optic applications, wall thickness. |
|
| Classical Monte Carlo Simulations of Relaxed Trapping Site Structures in Li Atom Doped Solid Ne. |
1993 |
|
| Authors:
M. E. Fajardo; PHILLIPS LAB EDWARDS AFB CA
|
| Results of classical Monte Carlo simulations of Li atom doped fcc Ne solids are presented. Li atom trapping sites based on four-atom and six-atom vacancies required only minor relaxation of the matrix surroundings to reach equilibrium. Trapping sites based on one-atom and two-atom vacancies were unstable and rearranged to yield crowded trapping sites which could be relieved by the incorporations of nearby additional vacancies. These results are all consistent with ... |
|
| Matrix Isolation Spectroscopy of Metal Atoms Generated by Laser Ablation: III. The Na/Ar, Na/Kr, and Na/Xe Systems. |
1993 |
|
| Authors:
S. Tam; M. E. Fajardo; PHILLIPS LAB EDWARDS AFB CA
|
| The results of matrix isolation experiments of Na atoms generated by pulsed laser ablation of sodium metal are reported. Novel effects previously observed in similarly prepared Li/Rg patrices apparently generalize to the Na/Rg systems. A new spectral feature appears in Na/Ar matrices with peaks near 504, 513, and 523 nm for which we have coined the name 'violet triplet' and assigned to Na atoms in a heretofore unaccessed trapping site. ... |
|
| Matrix Isolation Spectroscopy of Metal Atoms Generated by Laser Ablation: II. The Li/Ne, Li/Dsbus2, and Li/Hsub2 Systems. |
1993 |
|
| Authors:
M. E. Fajardo; PHILLIPS LAB EDWARDS AFB CA
|
| Results of experiments on lithium-doped cryogenic solids (Ne, Dsub2, and Hsub2) prepared by laser ablation of solid lithium are presented including near UV-visible absorption spectra and thermal annealing studies. Li atoms are found in more than one type of trapping site in each of the systems studied. In Li/Ne matrices deposited at T = 5 K, the main optical absorption feature is a so-called 'triplet' absorption with peaks near 628, ... |
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