PEGASUS is a 1.5 MJ capacitor bank facility used in the Los Alamos Trailmaster foil implosion program. The experiments on this facility are to serve as a diagnostic testbed and foil physics benchmark for foil implosions with explosive generators as drivers. During the first year of operation, foil implosions have been driven by discharging the bank directly into a very thin Aluminum 2500 A thick free-standing foil without any pulse sharpening techniques; so-called direct drive. These direct...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *IMPLOSIONS, ALUMINUM, CAPACITORS, FOILS(MATERIALS),...
A hydrogen rich, low density liquid, contained within the internal volume of a cylindrical liner, was requested of the Polymers and Coatings Group (MST-7) of the Los Alamos Materials Science Division for one of the last liner driven experiments conducted on the Los Alamos Pegasus facility. The experiment was a continuation of the Raleigh-Taylor hydrodynamics series of experiments and associated liners that have been described previously.
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *BUTANES, *EXPERIMENTAL DESIGN, *PARTICLE ACCELERATOR...
This report describes numerical computations for imploding staged cylinders. The calculations were made with the WOL's one-dimensional code, Wundy. Six different geometries were examined and the positions and velocities of the inner and outer surfaces of both the core and the staging were calculated. In the course of these calculations, a spurious oscillation arose and the steps taken to deal with it are described.
Topics: DTIC Archive, Coughlin, James P., NAVAL SURFACE WEAPONS CENTER WHITE OAK LAB SILVER SPRING MD,...
This research project focuses on prostate cancer, a devestating socioeconomic disease, whose detection is plagued with inadequate sensitivity and specificity. Hypoxia is the hallmark of malignancy because aggressive cancers outgrow their blood supply. We ultimately aim to build an instrument that combines OPtics and UltraSound (OPUS) to quantify hypoxia via optical imaging but with the improved spatial resolution of US imaging. Specifically, the acoustooptic effect will be used to nly modulate...
Topics: DTIC Archive, CALIFORNIA UNIV REGENTS SAN DIEGO LA JOLLA CA, *DETECTION, *OPTICAL IMAGES, *PROSTATE...
Magnetized target fusion (MTF) attempts to combine the favorable attributes of magnetic confinement fusion (MCF) for energy confinement with the attributes of inertial confinement fusion (ICF) for efficient compression heating and wall-free containment of the fusing plasma. It uses a material liner to compress and contain a magnetized plasma. For practical applications, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Spherically converging...
Topics: NASA Technical Reports Server (NTRS), INERTIAL CONFINEMENT FUSION, SPHERICAL PLASMAS, PLASMA...
The K-shell radiation emitted by the argon seeded in the DT fuel of a CO2 Laser driven microballoon implosion is modeled by post processing the results of a hydrodynamic (LANL) calculation. The entire K-shell spectrum is self-consistently calculated including: transport of both lines and continua, collisional-radiative equilibrium (CRE) number densities, Stark profiles for the first four resonance lines of Ar XVII and XVIII, and Voigt profiles for the remaining lines. The CRE ionic number...
Topics: DTIC Archive, Kepple,P C, NAVAL RESEARCH LAB WASHINGTON DC, *ARGON, *PLASMA DIAGNOSTICS, *SPECTRAL...
Light-ion beams, appropriate for use as inertial-confinement fusion drivers, can be transported in z-discharge channels over distances of several meters. Here stability considerations for light-ion beam transport in such channels are reviewed. Many aspects of the important velocity-space instabilities are considered and the resulting conditions for good transport are discussed. The results will be presented in a general form so that they may be applied to beams of various species (e.g. H+, D+,...
Topics: DTIC Archive, Ottinger,P F, NAVAL RESEARCH LAB WASHINGTON DC, *ION BEAMS, *TRANSPORT PROPERTIES,...
The formation and diagnostics of a cylindrical plasma shell suitable for electromagnetic implosion plasma generation is discussed. The plasma shell is formed by a 5 kV, 30 kVA, 6 microsecond risetime capacitor discharge through a 20 cm radius, 2 2 cm tall, 0.1 to 1.0 mg injected gas shell. The gas shell (H2, D2, He or Ar) is injected through a circular array of 36 Mach 6 nozzles, fed by a 100 to 1000 lb/sq. in., 3 cm fast gas valve. The injected gas flows axially through the electrode gap,...
Topics: DTIC Archive, Bengtson,Roger, TEXAS UNIV AT AUSTIN DEPT OF PHYSICS, *PLASMAS(PHYSICS), *SHAPE,...
A double-target technique is used to measure the uniformity with which laser irradiated thin foil targets are ablatively accelerated. Studies of the effects of laser nonuniformities on the target acceleration reveal an increase in smoothing (symmetrization) with increasing laser intensity. Measurements of targets accelerated to velocities (160 km/sec) sufficient for pellet fusion implosions are presented and discussed.
Topics: DTIC Archive, Obenschain,S P, NAVAL RESEARCH LAB WASHINGTON DC, *ABLATION, *FOILS(MATERIALS),...
DETAR Task 0rder 0016 supports the Air Force Research Laboratory's ongoing effort to demonstrate magnetized target fusion in a laboratory environment. The experimental premise involves forming a plasma in a field-reversed configuration (FRC), translating it a short distance from where it was formed into a cylindrical flux-conserving shell (solid liner), and then adiabatically compressing it to fusion-relevant densities and temperatures by imploding the liner around it. The name FRCHX, for FRC...
Topics: DTIC Archive, SCIENCE APPLICATIONS INTERNATIONAL CORP (SAIC) ALBUQUERQUE NM, *ADIABATIC CONDITIONS,...
The Laguna foil implosion experiments are part of the Los Alamos foil implosion project, Trailmaster. In the La- guna experiments we are fielding a system that should provide implosion energies of the order of 100 kJ. The Laguna pulse power system consists of a Mark IX helical generator, a 100-nH storage inductor which includes a post-hole convolute design, an explosively-formed fuse opening switch, a surface discharge closing switch, and a vacuum powerflow channel. The imploding plasma is...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *IMPLOSIONS, *PLASMAS(PHYSICS), ALUMINUM FOIL, CIRCUITS,...
We present computational studies on the use of colliding shell configurations to mitigate the effects of Magnetic Rayleigh-Taylor (MRT) on the inner liner. Two-dimensional MHD calculations of liners have been performed that have pre-formed single wavelength perturbations. Specifying the perturbation allows us to follow the evolution of a specific disturbance with little ambiguity. This technique has been confirmed in numerous experiments on the PEGASUS II machine. An inner liner is located at a...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *IMPLOSIONS, *MAGNETIC FIELDS, *RAYLEIGH WAVES,...
The plasma gate switch is a novel technique for producing a long conduction time vacuum opening switch. The switch consists of an aluminum foil which connects the cathode to the anode in a coaxial geometry. The foil is designed so that the maximum axial acceleration is in the center of the foil and that at the appropriate time, the center opens up and magnetic flux is carried down the gun to the load region. The switch is designed to minimize the amount of mass transported into the load region....
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *GATES(CIRCUITS), *PLASMA OPENING SWITCHES,...
A limited radiation-magnetohydrodynamics simulation code, ZPIMP, is used to predict radiation yields in various energy bins on a JUPITER-class machine. Elements of the simulation code are reviewed and calculations are made to compare the code with experimental K-shell yields from aluminum z-pinches on the SATURN generator. For a chosen viscosity parameter the simulated yields agree remarkably with the data. The same code is applied on an early version of the linear inductive voltage adder, but...
Topics: DTIC Archive, Giuliani, Jr , J L, NAVAL RESEARCH LAB WASHINGTON DC, *PLASMAS(PHYSICS), *ELECTRIC...
This report describes the safety evaluation of the 25-inch (diagonal) rectangular cathode-ray tube (CRT) that is used in the engineering model of the Electronic Tabular Display Subsystem (ETABS). An evaluation of ETABS will be performed at the Federal Aviation Administration (FAA) Technical Center for possible application in FAA Air Route Traffic Control Centers (ARTCC). The safety evaluation included standard industry pressure testing and special implosion testing on 12 CRT samples. Eleven of...
Topics: DTIC Archive, Wilson,Anthony R, FEDERAL AVIATION ADMINISTRATION TECHNICAL CENTER ATLANTIC CITY NJ,...
One of the critical elements for high gain target designs is the high degree of symmetry that must be maintained in the implosion process. The induced spatial incoherence (ISI) concept has some promise for reducing ablation pressure nonuniformities to about 1%. The ISI method produces a spatial irradiance profile that undergoes large random fluctuations on picosecond time scales but is smooth on long time scales. The ability of the ISI method to produce a nearly uniform ablation pressure is...
Topics: DTIC Archive, Emery, M H, NAVAL RESEARCH LAB WASHINGTON DC, *FREQUENCY, SPATIAL DISTRIBUTION,...
Pulse power systems delivering in excess of 100 MJ represent one of the next major challenges to the pulse power community. While a laboratory pulse power system in this energy range is feasible, it represents a very substantial investment of both time and resources. Prudence requires that fundamental proof-of-principle for the contemplated application is established before such massive resources are committed. Explosive pulse power systems using magnetic flux compression provide a direct path...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *COMPRESSORS, *GENERATORS, *HIGH ENERGY, *MAGNETIC...
We investigate analytically and numerically the effects of tailoring the density profile in a laser target in order to decrease imprinting of mass perturbations due to the long-wavelength modes. Inverting the acceleration of the ablation front during the shock transit time could reduce the early-time mass perturbation amplitudes developed in the target after the shock transit. This principle was first suggested for mitigating the RT instability of imploding Z-pinches [Velikovich et al., Phys....
Topics: DTIC Archive, Metzler, Nathan, NUCLEAR RESEARCH CENTER NEGEV BEERSHEBA (ISRAEL) PHYSICAL DEPT,...
We describe the optical diagnostics used to measure magnetic fields up to 11 MGauss (1100 T) produced by Russian MC1 magnetic flux compression generators propelled by American high explosives in a joint experiment. The fields were measured by Faraday rotation in glass samples placed between thin polarizers. Light was introduced and collected in multi-mode fiber optics, allowing the laser light source and the recording instrumentation to be housed in a bunker about 20 m from the explosion. Great...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *GENERATORS, *HIGH EXPLOSIVES, *MAGNETIC FIELDS,...
This report, the final technical report for the Advanced Cold X-Ray Source Program, describes experimental research efforts to develop plasma radiation sources (PRS) for the simulation of cold x-ray effects. On the Double-EAGLE generator we have investigated four advanced PRS loads: large-diameter aluminum wire array, aluminum/ magnesium wire array, argon/titanium puff-on-wire, and aluminum/titanium wire array. On the Saturn generator we have investigated aluminum/magnesium wire arrays and...
Topics: DTIC Archive, Riordan, John C, MAXWELL PHYSICS INTERNATIONAL SAN LEANDRO CA, *X RAY DIAGNOSTICS, *X...
With long pulse, moderate intensity Nd-laser irradiation of flat targets, time-integrated images of emission reveal filaments along the laser axis. Combined with fine-scale structure found in time-integrated images of x-ray emission, these filaments suggest self-focusing of hot spots in the incident beam.
Topics: DTIC Archive, Herbst,M J, NAVAL RESEARCH LAB WASHINGTON DC, *LASER BEAMS, *X RAY DIAGNOSTICS,...
The basic idea that motivated this research effort is the prospect that a series of time z-pinch plasma implosions could be used to sequentially propel a projectile to high velocities. Such a process would provide a new type of electrically driven gun with the potential for achieving projectile velocities well above those attainable by chemical guns. The concept in its earliest form appears to have the attractive feature of being potentially rep-ratable. The current flows axially along sections...
Topics: DTIC Archive, Tidman, D A, JAYCOR ALEXANDRIA VA, *ELECTRIC GUNS, *PINCH EFFECT, DYNAMIC LOADS,...
The aim of the Trailmaster series of experiments is to generate an intense source of soft x-rays by imploding a thin (2000 A) aluminum cylinder.1 The present scheme incorporates a plasma flow switch for the final pulse shaping and requires careful diagnostic analysis. The emphasis of this work is to transfer the energy to the load area and to understand the dynamics of the plasma flow switch.2 The experiments are carried out at LANL in two facilities. Laboratory experiments that answer...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *PLASMAS(PHYSICS), ALUMINUM, CAPACITORS, ELECTRIC...
A comprehensive gas puff capability is being developed on the Z pulsed power generator. We describe the methodology employed for developing a gas puff load on Z, which combines characterization and modeling of the neutral gas mass flow from a supersonic nozzle, numerical modeling of the implosion of this mass profile, and experimental evaluation of these magnetic implosions on Z. We are beginning a multi-year science program to study gas puff z-pinch physics at high current, starting with an...
Topics: DTIC Archive, SANDIA NATIONAL LABS ALBUQUERQUE NM, *IMPLOSIONS, ELECTRIC GENERATORS, GAS FLOW,...
A sequence of laser pulses focussed onto the same spot on a target produces evaporation of target material and the formation of a crater with crater depth increasing from shot to shot. An experimental study of the crater- depth dependence of the magnetic fields generated by the laser produced plasmas has been performed. Repeated irradiation of an aluminum target with a laser pulse of 10 to the 12th power W/cm squared in a low background pressure of air at 10 to the (-5) power Torr produced...
Topics: DTIC Archive, Williamson, Jr, Francis T, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *LASER BEAMS,...
Temperatures and densities were determined from the plasma implosion formed at the center of symmetrical exploded-wire arrays. Temperatures of 500-850 eV were found from line ratios in Al and Si shots using various plasma models. The recombination temperatures for these elements were 400-500 eV. Higher implosion temperatures of 1.5 to 2 keV were found in Ti and Fe shots and of 2.5 to 4 keV for Mo wire shots. The densities were approximately 1 x 10 to the 20th power el/cu cm for the...
Topics: DTIC Archive, Burkhalter,P, NAVAL RESEARCH LAB WASHINGTON D C, *EMISSION SPECTRA, *X RAY SPECTRA,...
The explosive and implosive magnetic generators of frequency (EMGF and lMGF) consist of a spiral magnetocumulative generator (MCG) with a small capacitive load. The simplest model describing the operation of these devices is based on their equivalent circuit diagram. By selecting the proper parameters of the lMGF and EMGF, it is possible to calculate the current in the coil and to obtain good agreement between the calculated and measured envelopes of the current waveform The particular...
Topics: DTIC Archive, ARMY MISSILE DEFENSE AND SPACE TECHNOLOGY CENTER HUNTSVILLE AL, *EQUIVALENT CIRCUITS,...
This report describes the work of the Radiation Hydrodynamics Branch during FY 98 in support of the DTRA PRS program. Critical issues covered are: (1) Large initial radius Z-pinch load behavior on Saturn, Double Eagle, DECADE QUAD, and Z pulsed power machines, (2) Analyzing temperature and density radial temperature gradients in Z-pinch plasmas, (3) Analysis of time resolved and time integrated Z-pinch data, (4) Spectroscopic PRS analysis, (5) Radiation magnetohydrodynamic code development and...
Topics: DTIC Archive, NAVAL RESEARCH LAB WASHINGTON DC RADIATION HYDRODYNAMICS BRANCH,...
The UTIAS explosive-driven-implosion facility was used to produce stable, centered and focused hemispherical implosions to generate neutrons from D-D reactions. A high resolution scintillator-detection system measured the neutrons and gamma-rays resulting from the fusion of deuterium. Several approaches were used to initiate fusion in deuterium. The simpliest and most direct proved to be in predetonated stoichiometric mixture of deuterium-oxygen. The other successful method was miniature...
Topics: DTIC Archive, Sagie, D., TORONTO UNIV DOWNSVIEW (ONTARIO) INST FOR AEROSPACE STUDIES, *EXPLOSIONS,...
This report describes the work of the Radiation Hydrodynamics Branch during FY 2002 in support of the DTRA PRS Program Critical issues covered are: (1) side-on and end-on x-ray imaging of wire and gas puff implosions, (2) multi-group radiative diffusion, (3) discussions of radiation transport that includes pitfalls inherent to radiation modeling of Z-pinch plasmas, (4) K-shell yield performance assessment of argon loads on DTRA machines, (5) Z-pinch-driven direct drive inertial confinement...
Topics: DTIC Archive, Davis, J, NAVAL RESEARCH LAB WASHINGTON DC, *RADIATION, *HYDRODYNAMICS, *IMPLOSIONS,...
Ablative acceleration of thin foil targets at low laser irradiance (10 to the 12th power -10 to the 13th power W/sq cm) are studied experimentally and theoretically. Ablative acceleration of foils up to approximately 10 to the 7th power cm/sec with good hydrodynamic efficiency (20%) have been achieved. These and other results are in good agreement with a simple rocket model. (Author)
Topics: DTIC Archive, Decoste,R, NAVAL RESEARCH LAB WASHINGTON DC, *ABLATION, *FOILS(MATERIALS), *LASER...
The symmetric implosion of pellet shells will require sideways thermal transport smoothing of any laser intensity nonuniformities. A scaling law shows a surprisingly strong laser wavelength dependence for this smoothing mechanism; it places a large premium on the use of longer wavelength near-infrared lasers. This smoothing requirement conflicts with the advantages of shorter laser wavelengths for controlling deleterious plasma instabilities. (Author)
Topics: DTIC Archive, Gardner,J H, NAVAL RESEARCH LAB WASHINGTON DC, *LASER INDUCED FUSION, STABILITY,...
The Air Force Research Laboratory Directed Energy Directorate (AFRL/DE) has, over the last several years, conducted experiments on the magnetic pressure driven implosion of various metal shells (solid liners). More recently, AFRL/DE has reported on experiments that successfully imploded cylindrical aluminum liners suitable for compressing field reversed configurations (FRC's) to magnetized target fusion (MTF) conditions. We have recently done Mach2 MHD simulations of the resistive heating of...
Topics: DTIC Archive, AIR FORCE RESEARCH LAB KIRTLAND AFB NM DIRECTED ENERGY DIRECTORATE, *IMPLOSIONS,...
This report describes the work of the Radiation Hydrodynamics Branch during FY 2004 in support of the DTRA's PRS and Sandia National Laboratories high energy density programs. It is a compilation of articles that were co-authored by Branch members. The titles are: (1) Controlling uniformity of gas-puff and wire array implosions with wire current-carrying structures, (2) Two- and three-wire loads for large current machines, (3) Enhanced energy coupling and X-ray emission in Z-pinch plasma...
Topics: DTIC Archive, Davis, J, NAVAL RESEARCH LAB WASHINGTON DC, *X RAYS, *IMPLOSIONS, *Z PINCH PLASMAS,...
This document is a manual for the use of the Smooth Particle Hydrodynamics Code (SPHC). This code offers rapid hydrodynamic simulations with no large degradation in simulation accuracy. It has been successfully used to simulate implosions, explosions, shock tubes and to monitor aggregate masses under hydrodynamic conditions. In addition, SPHC can divide, create, and subtract particles in the simulations to optimize results without adversely affecting run conditions. The code is written in the C...
Topics: DTIC Archive, Stellingwerf, R, MISSION RESEARCH CORP ALBUQUERQUE NM, *HYDRODYNAMIC CODES,...
354
354
Jun 21, 2010
06/10
by
NON
texts
eye 354
favorite 0
comment 0
Mariner Venus-Mercury 1973 imaging experiment for mapping Mercury and error rates for science words
Topics: HYPERVELOCITY GUNS, IMPLOSIONS, LIGHT GAS GUNS, EXPLOSIVES
Line widths have been measured on spectra from implosions with the Gamble II generator. The K-shell transitions from sodium ions were observed with a curved crystal x-ray spectrograph and imaged with a pinhole camera. The various contributions to spectral line broadening were analyzed. The conclusion is that the line widths were comprised essentially of a source broadening due to the finite plasma size and a plasma broadening due to the ion motion during the implosion final stage. Despite the...
Topics: DTIC Archive, Mehlman, G, NAVAL RESEARCH LAB WASHINGTON DC, *IMPLOSIONS, *PLASMAS(PHYSICS),...
Magnetized Target Fusion (MTF) is a pulsed approach that compresses magnetized fuel to achieving burning hydrogen plasma conditions. The compression in one MTF-scenario comes from uses a conducting liner that is imploded due to the action of high electrical currents that flow on the outer surface of the liner. This implosion compresses and heats a dense, warm magnetized deuterium or deuterium-tritium plasma. In the present work, MHD numerical simulations of a representative MTF configuration...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *ELECTRICAL CONDUCTIVITY, *IMPLOSIONS, *PLASMAS(PHYSICS),...
High temperature radiation sources exceeding one hundred eV can be produced via z-pinches using currently available pulsed power. The usual approach to compare the z-pinch simulation and experimental data is to convert the radiation output at the source, whose temperature and density distributions are computed from the 2-D MHD code, into simulated data such as a spectrometer reading. This conversion process involves a radiation transfer calculation through the axially symmetric source, assuming...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *RADIATION, AXISYMMETRIC, DETECTORS, FOILS(MATERIALS),...
This thesis, a single case study, focuses on the manner in which Belarus handles the sovereignty that it acquired during the implosion of the Soviet Union. Various Belarusian factors likely to generate or to foster national identity and state independence are examined. None of them (ethno-cultural patterns, institutions and politics, attitudes of the Belarusian people) gives reason for optimism. Belarusian national identity is poorly developed and unable to serve as a formative factor in...
Topics: DTIC Archive, Haselbach, Carl, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *POLITICAL SCIENCE, *RUSSIA,...
This report details the work of the Plasma Radiation Branch conducted in FY 86 with respect to several critical problems concerning the design of Z pinch implosions and the optimization of their radiative output. Separate sections describe progress in atomic modeling of K shell copper radiation, radiation hydrodynamics, argon implosions, design of anti-zippering nozzles, and analyses of anomalous resistivity and plasma opening switches.
Topics: DTIC Archive, NAVAL RESEARCH LAB WASHINGTON DC, *PLASMAS(PHYSICS), *IMPLOSIONS, RADIATION,...
The objective of this effort was to identify, develop, and evaluate conceptual design options for an affordable full certification simulator. To limit the scope of our study, we focused on systems capable of delivering 400 kJ of krypton k-shell (13 keV lines) radiation from imploding plasma radiation sources (PRS). We were primarily concerned with selecting pulsed power drivers and the associated pulsed power technology needed to drive PRS implosions of 100 and 250 ns at 30 to 60 MA levels. Our...
Topics: DTIC Archive, Spence, Phil, TITAN CORP SAN LEANDRO CA PULSE SCIENCES DIV, *SIMULATORS, *ENERGY...
A novel type of luminescence has been studied from steam vapor bubbles condensing in sea water and tap water. A possible application to the light observed at deep sea hydrothermal vents is discussed.
Topics: DTIC Archive, Reynolds, G T, PRINCETON UNIV NJ JOSEPH HENRY LABS OFPHYSICS, *BUBBLES,...
Pulsed power hydrodynamics experiments typically involve multi-megajoule capacitor banks, imploding thin-walled cylinders of solid-density metal by the electromagnetic force associated with axial currents in excess of ten megamperes. Much of this activity operates with technology developed for other applications (e.g., soft X-ray generation), which can be significantly larger than actually required for the scientific objectives of such experiments. This is particularly true, if imaging...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *HYDRODYNAMICS, IMPLOSIONS, LABORATORY EQUIPMENT,...
This report describes the work of the Radiation Hydrodynamics Branch during FY 95 in support of the DNA PRS program. Critical issues covered are: (1) Design and diagnosis of ACE 4 simulator experiments, (2) Investigations of K-shell emission from medium atomic number elements, (3) Non-thermal warm x-rays, (4) puff-on-wire Z pinch loads, (5) Implosion stability, (6) Stabilization of implosions through rotation, (7) Diagnosing medium atomic number plasmas, (8) Calculating measurable radiation...
Topics: DTIC Archive, NAVAL RESEARCH LAB WASHINGTON DC RADIATION HYDRODYNAMICS BRANCH, *PLASMAS(PHYSICS),...
This presentation describes: the theory of ultrasonics, cavitation and implosion; the importance and application of ultrasonics in precision cleaning; explanations of ultrasonic cleaning equipment options and their application; process parameters for ultrasonic cleaning; and proper operation of ultrasonic cleaning equipment to achieve maximum results.
Topics: NASA Technical Reports Server (NTRS), CAVITATION FLOW, IMPLOSIONS, ULTRASONIC CLEANING,...
The basic idea that motivated this research effort is the prospect that a series of time z-pinch plasma implosions could be used to sequentially propel a projectile to high velocities. Such a process would provide a new type of electrically driven gun with the potential for achieving projectile velocities well above those attainable by chemical guns. The concept in its earliest form appears to have the attractive feature of being potentially rep-ratable. The current flows axially along sections...
Topics: DTIC Archive, Tidman, D A, JAYCOR ALEXANDRIA VA, *ELECTRIC GUNS, *PINCH EFFECT, DYNAMIC LOADS,...
If acoustic cavitation is produced in a liquid, the implosion of cavities can heat the internal contents of the bubble to incandescent temperatures. The electromagnetic emissions associated with this energy concentration can often be seen with the naked eye. This phenomenon, in which light is generated by sound is called sonoluminescence. A particular form of this phenomenon is called single-bubble sonoluminescence. This form is much easily to study because the fundamental bubble dynamics that...
Topics: DTIC Archive, Crum, Lawrence A, WASHINGTON UNIV SEATTLE APPLIED PHYSICS LAB, *BUBBLES,...
The theoretical work previously done on Rayleigh Taylor instability in compressible fluids has been reviewed in a chapter written for the Encyclopedia of Fluid Mechanics, to be published by Gulf. The physical basis of the instability, the dependence of growth rate on a adiabatic index gamma, and the stability of uniform self similar implosions and expansions are discussed.
Topics: DTIC Archive, Book, D. L., NAVAL RESEARCH LAB WASHINGTON DC, *RAYLEIGH TAYLOR INSTABILITY,...
Plasma flow switch experiments conducted on Pegasus have shown that a conducting layer of plasma shunts the load slot preventing efficient switching of current to the load. This effect is seen computationally. The magnitude of the effect depends on the specific parameters of the switch plasma and current level. Computations have also shown that a plasma boundary layer trap would effectively remove enough plasma from the inner conductor of the power flow channel so that efficient switching would...
Topics: DTIC Archive, LOS ALAMOS NATIONAL LAB NM, *PLASMA OPENING SWITCHES, BOUNDARY LAYER, CAPACITORS,...
