WorldWideScience

Sample records for vapor explosion experiments

  1. Installation for low temperature vapor explosion experiment

    International Nuclear Information System (INIS)

    Nilsuwankosit, Sunchai; Archakositt, Urith

    2000-01-01

    A preparation for the experiment on the low temperature vapor explosion was planned at the department of Nuclear Technology, Chulalongkorn University, Thailand. The objective of the experiment was to simulate the interaction between the molten fuel and the volatile cooling liquid without resorting to the high temperature. The experiment was expected to involve the injection of the liquid material at a moderate temperature into the liquid material with the very low boiling temperature in order to observe the level of the pressurization as a function of the temperatures and masses of the applied materials. For this purpose, the liquid nitrogen and the water were chosen as the coolant and the injected material for this experiment. Due to the size of the installation and the scale of the interaction, only lumped effect of various parameters on the explosion was expected from the experiment at this initial stage. (author)

  2. R-22 vapor explosions

    International Nuclear Information System (INIS)

    Anderson, R.P.; Armstrong, D.R.

    1977-01-01

    Previous experimental and theoretical studies of R-22 vapor explosions are reviewed. Results from two experimental investigations of vapor explosions in a medium scale R-22/water system are reported. Measurements following the drop of an unrestrained mass of R-22 into a water tank demonstrated the existence of two types of interaction behavior. Release of a constrained mass of R-22 beneath the surface of a water tank improved the visual resolution of the system thus allowing identification of two interaction mechansims: at low water temperatures, R-22/water contact would produce immediate violent boiling; at high water temperatures a vapor film formed around its R-22 as it was released, explosions were generated by a surface wave which initiated at a single location and propagated along the vapor film as a shock wave. A new vapor explosion model is proposed, it suggests explosions are the result of a sequence of three independent steps: an initial mixing phase, a trigger and growth phase, and a mature phase where a propagating shock wave accelerates the two liquids into a collapsing vapor layer causing a high velocity impact which finely fragments and intermixes the two liquids

  3. A study on vapor explosions

    International Nuclear Information System (INIS)

    Takagi, N.; Shoji, M.

    1979-01-01

    An experimental study was carried out for vapor explosions of molten tin falling in water. For various initial metal temperatures and subcooling of water, transient pressure of the explosions, relative frequency of the explosions and the position where the explosions occur were measured in detail. The influence of ambient pressure was also investigated. From the results, it was concluded that the vapor explosion is closely related to the collapse of a vapor film around the molten metal. (author)

  4. The vapor pressures of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Ewing, Robert G.; Waltman, Melanie J.; Atkinson, David A.; Grate, Jay W.; Hotchkiss, Peter

    2013-01-05

    The vapor pressures of many explosive compounds are extremely low and thus determining accurate values proves difficult. Many researchers, using a variety of methods, have measured and reported the vapor pressures of explosives compounds at single temperatures, or as a function of temperature using vapor pressure equations. There are large variations in reported vapor pressures for many of these compounds, and some errors exist within individual papers. This article provides a review of explosive vapor pressures and describes the methods used to determine them. We have compiled primary vapor pressure relationships traceable to the original citations and include the temperature ranges for which they have been determined. Corrected values are reported as needed and described in the text. In addition, after critically examining the available data, we calculate and tabulate vapor pressures at 25 °C.

  5. Headspace concentrations of explosive vapors in containers designed for canine testing and training: theory, experiment, and canine trials.

    Science.gov (United States)

    Lotspeich, Erica; Kitts, Kelley; Goodpaster, John

    2012-07-10

    It is a common misconception that the amount of explosive is the chief contributor to the quantity of vapor that is available to trained canines. In fact, this quantity (known as odor availability) depends not only on the amount of explosive material, but also the container volume, explosive vapor pressure and temperature. In order to better understand odor availability, headspace experiments were conducted and the results were compared to theory. The vapor-phase concentrations of three liquid explosives (nitromethane, nitroethane and nitropropane) were predicted using the Ideal Gas Law for containers of various volumes that are in use for canine testing. These predictions were verified through experiments that varied the amount of sample, the container size, and the temperature. These results demonstrated that the amount of sample that is needed to saturate different sized containers is small, predictable and agrees well with theory. In general, and as expected, once the headspace of a container is saturated, any subsequent increase in sample volume will not result in the release of more vapors. The ability of canines to recognize and alert to differing amounts of nitromethane has also been studied. In particular, it was found that the response of trained canines is independent of the amount of nitromethane present, provided it is a sufficient quantity to saturate the container in which it is held. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. Vapor Explosions with Subcooled Freon

    International Nuclear Information System (INIS)

    Henry, R.E.; Fauske, Hans K.; McUmber, L.M.

    1976-01-01

    Explosive vapor formation accompanied by destructive shock waves, can be produced when two liquids, at much different temperatures, are brought into intimate contact. A proposed analytical model states that the interface temperature upon contact between the two liquid systems, gust be greater than or equal to the spontaneous nucleation temperature of that liquid-liquid system and that the thermal boundary layer must be sufficiently developed to support a critical size cavity. For time scales greater than 10-12 sec, the interface temperature upon contact of two semi-infinite masses, with constant thermal properties, can be related to the initial liquid temperatures. The spontaneous nucleation behavior at the interface can either be heterogeneous or homogeneous in nature. In either case, the critical size cavities, which initiate the vaporization process, are produced by local density fluctuations within the cold liquid. For homogeneous conditions, the two liquids present a well-wetted system and the vapor embryos are produced entirely within the cold liquid. For heterogeneous conditions, which result from poor, or imperfect wetting, at the liquid-liquid interface, the critical sized cavities are created at the interface at somewhat lower temperatures. A sequence of experiments, using Freon-22 and water, Freon-22 and mineral oil, and Freon-12 and mineral oil have been performed to test this spontaneous nucleation premise. For Freon-22 at its normal boiling point, the interface temperature of the water must be at least 77 deg. C before the interface temperature equals or exceeds the minimum homogeneous nucleation value of 54 deg. C and 84 deg. C before the interface temperature equals 60 deg. C where the homogeneous nucleation rate becomes truly explosive. The Freon-water test demonstrated explosive interactions for water temperatures considerably lower than this value and this was attributed to the heterogeneous nucleation characteristics of that particular system

  7. Liquid-liquid contact in vapor explosion

    International Nuclear Information System (INIS)

    Segev, A.

    1978-08-01

    The contact of two liquid materials, one of which is at a temperature substantially above the boiling point of the other, can lead to fast energy conversion and a subsequent shock wave. This phenomenon is called a vapor explosion. One method of producing intimate, liquid-liquid contact (which is known to be a necessary condition for vapor explosion) is a shock tube configuration. Such experiments in which water was impacted upon molten aluminum showed that very high pressures, even larger than the thermodynamic critical pressure, could occur. The mechanism by which such sharp pressure pulses are generated is not yet clear. The report describes experiments in which cold liquids (Freon-11, Freon-22, water, or butanol) were impacted upon various hot materials

  8. Vapor generation methods for explosives detection research

    Energy Technology Data Exchange (ETDEWEB)

    Grate, Jay W.; Ewing, Robert G.; Atkinson, David A.

    2012-12-01

    The generation of calibrated vapor samples of explosives compounds remains a challenge due to the low vapor pressures of the explosives, adsorption of explosives on container and tubing walls, and the requirement to manage (typically) multiple temperature zones as the vapor is generated, diluted, and delivered. Methods that have been described to generate vapors can be classified as continuous or pulsed flow vapor generators. Vapor sources for continuous flow generators are typically explosives compounds supported on a solid support, or compounds contained in a permeation or diffusion device. Sources are held at elevated isothermal temperatures. Similar sources can be used for pulsed vapor generators; however, pulsed systems may also use injection of solutions onto heated surfaces with generation of both solvent and explosives vapors, transient peaks from a gas chromatograph, or vapors generated by s programmed thermal desorption. This article reviews vapor generator approaches with emphasis on the method of generating the vapors and on practical aspects of vapor dilution and handling. In addition, a gas chromatographic system with two ovens that is configurable with up to four heating ropes is proposed that could serve as a single integrated platform for explosives vapor generation and device testing. Issues related to standards, calibration, and safety are also discussed.

  9. Liquid--liquid contact in vapor explosion

    International Nuclear Information System (INIS)

    Segev, A.

    1978-08-01

    The contact of two liquid materials, one of which is at a temperature substantially above the boiling point of the other, can lead to fast energy conversion and a subsequent shock wave. This well-known phenomenon is called a ''vapor explosion.'' One method of producing intimate, liquid--liquid contact (which is known to be a necessary condition for vapor explosion) is a shock tube configuration. Such experiments in which water was impacted upon molten aluminum showed that very high pressures, even larger than the thermodynamic critical pressure, could occur. The mechanism by which such sharp pressure pulses are generated is not yet clear. In this experiment cold liquids (Freon-11, Freon-22, water, or butanol) were impacted upon various hot materials (mineral oil, silicone oil, water, mercury, molten Wood's metal or molten salt mixture). The main conclusion from the experimental study is that hydrodynamic effects may be very significant in any shock tube analyses, especially when multiple interactions are observed. A theoretical study was performed to check the possibility of vapor film squeezing (between a drop in film boiling and a surface) as a controlling mechanism for making liquid--liquid contact. Using experimental data, the film thickness was calculated and it was found to be too thick for any conceivable film rupture mechanism. It was suggested that the coalescence is a two-stage process, in which the controlling stage depends mainly on temperature and surface properties and can be described as the ability of cold liquid to spread on a hot surface

  10. Effect of degree of subcooling on vapor explosion

    International Nuclear Information System (INIS)

    Xu Zhihong; Yang Yanhua; Li Tianshu

    2010-01-01

    In order to investigate the mechanism of the vapor explosion, an observable experiment equipment for low-temperature molten materials to be dropped into water was designed. In the experiment, molten material jet was injected into water to experimentally obtain the visualized information. This experiment results show that the degree of subcooling restrains the explosion. In order to validate the result by other aspects, the breakup experiment was conducted. Results show that the degree of water subcooling is important to melt breakup. High temperature of water is easy to increase the vapor generation during molten material falling, which decrease the drag and accelerated the molten material falling. At the same time, more vapor appear around the molten metal decrease the heat transfer amount between water and molten materials. The two experimental results coincide. (authors)

  11. Final report on the small-scale vapor-explosion experiments using a molten NaCl--H2O system

    International Nuclear Information System (INIS)

    Anderson, R.P.; Bova, L.

    1976-04-01

    Vapor explosions were produced by injecting small quantities of water into a container filled with molten NaCl. Minimum explosion efficiencies, as evaluated from reaction-impulse measurements, were relatively large. Subsurface movies showed that the explosions resulted from a two-step sequence: an initial bulk-mixing phase in which the two liquids intermix on a large scale, but remain locally separated by an insulating gas-vapor layer; and a second step, immediately following breakdown of the gas layer, during which the two liquids locally fragment, intermix, and pressurize very rapidly. The experimental results were compared with various mechanistic models that had been proposed to explain vapor explosions. Early models seemed inconsistent with the results. More recent theories suggest that vapor explosions may be caused by a nucleation limit or by dynamic mixing combined with high surface-heat-transfer rates. Both types of models are consistent with the results

  12. A Local Propagation for Vapor Explosions

    International Nuclear Information System (INIS)

    Ochiai, M.; Bankoff, S.G.

    1976-01-01

    Explosive boiling, defined as energy transfer leading to formation of vapor rapidly enough to produce large shock waves, has been widely studied in a number of contexts. Depending upon the nature and temperatures of the liquids and mode of contacting, large-scale mixing and explosive vaporization may occur, or alternatively, only relatively non-energetic, film-type boiling may exist. The key difference is whether a mechanism is operative for increasing the liquid-liquid interfacial area in a time scale consistent with the formation of a detonation wave. Small drops of a cold volatile liquid were dropped onto a free surface of a hot, non-volatile liquid. The critical Weber number for coalescence is obtained from the envelope of the film boiling region. Markedly different behavior for the two hot liquids is observed. A 'splash' theory for local propagation of vapor explosions in spontaneously nucleating liquid-liquid systems is now formulated. After a random contact is made, explosive growth and coalescence of the vapor bubbles occurs as soon as the surrounding pressure is relieved, resulting in a high-pressure vapor layer at the liquid-liquid contact area. This amounts to an impact pressure applied to the free surface, with a resulting velocity distribution obtained from potential flow theory. The peak pressure predictions are. consistent with data for Freon-oil mixing, but further evaluation will await additional experimental data. Nevertheless, the current inference is that a UO 2 -Na vapor explosion in a reactor environment cannot be visualized. In conclusion: The propagation model presented here differs in some details from that of Henry and Fauske, although both are consistent with some peak pressure data obtained by Henry, et al. Clearly, additional experimental information is needed for further evaluation of these theories. Nevertheless, it should be emphasized that even at this time a number of important observations concerning the requirements for a vapor

  13. Effects of molten material temperatures and coolant temperatures on vapor explosion

    Institute of Scientific and Technical Information of China (English)

    LI Tianshu; YANG Yanhua; YUAN Minghao; HU Zhihua

    2007-01-01

    An observable experiment facility for low-temperature molten materials to be dropped into water was set up in this study to investigate the mechanism of the vapor explosion. The effect of the fuel and coolant interaction(FCI) on the vapor explosion during the severe accidents of a fission nuclear reactor has been studied. The experiment results showed that the molten material temperature has an important effect on the vapor explosion behavior and pressure. The increase of the coolant temperature would decrease the pressure of the vapor explosion.

  14. Similarities and differences in vapor explosion criteria

    International Nuclear Information System (INIS)

    Cronenberg, A.W.

    1978-01-01

    An overview of recent ideas pertaining to vapor explosion criteria indicates that in general sense, a consensus of opinion is emerging on the conditions applicable to explosive vaporization. Experimental and theoretical work has lead a number of investigators to the formulation of such conditions which are quite similar in many respects, although the quantitative details of the model formulation of such conditions are somewhat different. All model concepts are consistent in that an initial period of stable film boiling, separating molten fuel from coolant, is considered necessary (at least for large-scale interactions and efficient intermixing), with subsequent breakdown of film boiling due to pressure and/or thermal effects, followed by intimate fuel-coolant contact and a rapid vaporization process which is sufficient to cause shock pressurization. Although differences arise as to the conditions for and the energetics associated with film boiling destabilization and the mode and energetics of fragmentation and intermixing. However, the principal area of difference seems to be the question of what constitutes the requisite condition(s) for rapid vapor production to cause shock pressurization

  15. Study of film boiling collapse behavior during vapor explosion

    International Nuclear Information System (INIS)

    Yagi, Masahiro; Yamano, Norihiro; Sugimoto, Jun; Abe, Yutaka; Adachi, Hiromichi; Kobayashi, Tomoyoshi.

    1996-06-01

    Possible large scale vapor explosions are safety concern in nuclear power plants during severe accident. In order to identify the occurrence of the vapor explosion and to estimate the magnitude of the induced pressure pulse, it is necessary to investigate the triggering condition for the vapor explosion. As a first step of this study, scooping analysis was conducted with a simulation code based on thermal detonation model. It was found that the pressure at the collapse of film boiling much affects the trigger condition of vapor explosion. Based on this analytical results, basic experiments were conducted to clarify the collapse conditions of film boiling on a high temperature solid ball surface. Film boiling condition was established by flooding water onto a high temperature stainless steel ball heated by a high frequency induction heater. After the film boiling was established, the pressure pulse generated by a shock tube was applied to collapse the steam film on the ball surface. As the experimental boundary conditions, materials and size of the balls, magnitude of pressure pulse and initial temperature of the carbon and stainless steel balls were varied. The transients of pressure and surface temperature were measured. It was found that the surface temperature on the balls sharply decreased when the pressure wave passed through the film on balls. Based on the surface temperature behavior, the film boiling collapse pattern was found to be categorized into several types. Especially, the pattern for stainless steel ball was categorized into three types; no collapse, collapse and reestablishment after collapse. It was thus clarified that the film boiling collapse behavior was identified by initial conditions and that the pressure required to collapse film boiling strongly depended on the initial surface temperature. The present results will provide a useful information for the analysis of vapor explosions based on the thermal detonation model. (J.P.N.)

  16. Liquid-liquid contact in vapor explosion. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Segev, A.

    1978-08-01

    The contact of two liquid materials, one of which is at a temperature substantially above the boiling point of the other, can lead to fast energy conversion and a subsequent shock wave. This phenomenon is called a vapor explosion. One method of producing intimate, liquid-liquid contact (which is known to be a necessary condition for vapor explosion) is a shock tube configuration. Such experiments in which water was impacted upon molten aluminum showed that very high pressures, even larger than the thermodynamic critical pressure, could occur. The mechanism by which such sharp pressure pulses are generated is not yet clear. The report describes experiments in which cold liquids (Freon-11, Freon-22, water, or butanol) were impacted upon various hot materials (mineral oil, silicone oil, water, mercury, molten Wood's metal or molten salt mixture).

  17. Detonation and fragmentation modeling for the description of large scale vapor explosions

    International Nuclear Information System (INIS)

    Buerger, M.; Carachalios, C.; Unger, H.

    1985-01-01

    The thermal detonation modeling of large-scale vapor explosions is shown to be indispensable for realistic safety evaluations. A steady-state as well as transient detonation model have been developed including detailed descriptions of the dynamics as well as the fragmentation processes inside a detonation wave. Strong restrictions for large-scale vapor explosions are obtained from this modeling and they indicate that the reactor pressure vessel would even withstand explosions with unrealistically high masses of corium involved. The modeling is supported by comparisons with a detonation experiment and - concerning its key part - hydronamic fragmentation experiments. (orig.) [de

  18. Kaliski's explosive driven fusion experiments

    International Nuclear Information System (INIS)

    Marshall, J.

    1979-01-01

    An experiment performed by a group in Poland on the production of DD fusion neutrons by purely explosive means is discussed. A method for multiplying shock velocities ordinarily available from high explosives by a factor of ten is described, and its application to DD fusion experiments is discussed

  19. Nuclear explosive driven experiments

    International Nuclear Information System (INIS)

    Ragan, C.E.

    1981-01-01

    Ultrahigh pressures are generated in the vicinity of a nuclear explosion. We have developed diagnostic techniques to obtain precise high pressures equation-of-state data in this exotic but hostile environment

  20. Constrained Vapor Bubble Experiment

    Science.gov (United States)

    Gokhale, Shripad; Plawsky, Joel; Wayner, Peter C., Jr.; Zheng, Ling; Wang, Ying-Xi

    2002-11-01

    Microgravity experiments on the Constrained Vapor Bubble Heat Exchanger, CVB, are being developed for the International Space Station. In particular, we present results of a precursory experimental and theoretical study of the vertical Constrained Vapor Bubble in the Earth's environment. A novel non-isothermal experimental setup was designed and built to study the transport processes in an ethanol/quartz vertical CVB system. Temperature profiles were measured using an in situ PC (personal computer)-based LabView data acquisition system via thermocouples. Film thickness profiles were measured using interferometry. A theoretical model was developed to predict the curvature profile of the stable film in the evaporator. The concept of the total amount of evaporation, which can be obtained directly by integrating the experimental temperature profile, was introduced. Experimentally measured curvature profiles are in good agreement with modeling results. For microgravity conditions, an analytical expression, which reveals an inherent relation between temperature and curvature profiles, was derived.

  1. Ignitability and explosibility of gases and vapors

    CERN Document Server

    Ma, Tingguang

    2015-01-01

    The book provides a systematic view on flammability and a collection of solved engineering problems in the fields of dilution and purge, mine gas safety, clean burning safety and gas suppression modeling. For the first time, fundamental principles of energy conservation are used to develop theoretical flammability diagrams and are then explored to understand various safety-related mixing problems. This provides the basis for a fully-analytical solution to any flammability problem. Instead of the traditional view that flammability is a fundamental material property, here flammability is discovered to be a result of the explosibility of air and the ignitability of fuel, or a process property. By exploring the more fundamental concepts of explosibility and ignitability, the safety targets of dilution and purge can be better defined and utilized for guiding safe operations in process safety. This book provides various engineering approaches to mixture flammability, benefiting not only the safety students, but al...

  2. Investigation on energetics of ex-vessel vapor explosion based on spontaneous nucleation fragmentation

    International Nuclear Information System (INIS)

    Liu, Jie; Koshizuka, Seiichi; Oka, Yoshiaki

    2002-01-01

    A computer code PROVER-I is developed for propagation phase of vapor explosion. A new thermal fragmentation model is proposed with three kinds of time scale for modeling instant fragmentation, spontaneous nucleation fragmentation and normal boiling fragmentation. The energetics of ex-vessel vapor explosion is investigated based on different fragmentation models. A higher pressure peak and a larger mechanical energy conversion ratio are obtained by spontaneous nucleation fragmentation. A smaller energy conversion ratio results from normal boiling fragmentation. When the delay time in thermal fragmentation model is near 0.0 ms, the pressure propagation behavior tends to be analogous with that in hydrodynamic fragmentation. If the delay time is longer, pressure attenuation occurs at the shock front. The high energy conversion ratio (>4%) is obtained in a small vapor volume fraction together with spontaneous nucleation fragmentation. These results are consistent with fuel-coolant interaction experiments with alumina melt. However, in larger vapor volume fraction conditions (α υ >0.3), the vapor explosion is weak. For corium melt, a coarse mixture with void fraction of more than 30% can be generated in the pre-mixing process because of its physical properties. In the mixture with such a high void fraction the energetic vapor explosion hardly takes place. (author)

  3. Deflagration explosion of an unconfined fuel vapor cloud

    International Nuclear Information System (INIS)

    Taki, S.; Ogawa, Y.

    1981-01-01

    In the reported study, explosions are produced by injecting a small amount of liquefied petroleum gas (LPG) into air. The ignition and subsequent evolution of the explosion of the unconfined vapor cloud are observed by the simultaneous use of direct photographs and pressure recording. The intensity of the compression waves generated by unconfined combustion are modeled on the basis of the solution of the conservation equations for the flow associated with a spherically symmetric expanding piston. The obtained results are compared with the measurements. It is pointed out that the development of unconfined fuel vapor cloud explosions can be divided into two stages, including a deflagration propagating in premixed gases, which is followed by a diffusion flame promoted by buoyancy and convection. The experimental result from the pressure measurement is found to be quantitatively consistent with the result obtained from the spherical piston model

  4. The ion mobility spectrometer for high explosive vapor detection

    International Nuclear Information System (INIS)

    Cohen, M.J.; Stimac, R.M.; Wernlund, R.F.

    1984-01-01

    The Phemto-Chem /SUP R/ Model 100 Ion Mobility Spectrometer (IMS) operates in air and measures a number of explosive vapors at levels as low as partsper-trillion in seconds. The theory and operation of this instrument is discussed. The IMS inhales the vapor sample in a current of air and generates characteristic ions which are separated by time-of -ion drift in the atmospheric pressure gas. Quantitative results, using a dilution tunnel and standard signal generator with TNT, nitroglycerine, ethylene glycol dinitrate, cyclohexanone, methylamine, octafluoronaphthalene and hexafluorobenzene, are given. Rapid sample treatment with sample concentrations, microprocessor signal readout and chemical identification, offer a realistic opportunity of rapid explosive vapor detection at levels down to 10 -14 parts by volume in air

  5. Analysis of supercritical vapor explosions using thermal detonation wave theory

    Energy Technology Data Exchange (ETDEWEB)

    Shamoun, B.I.; Corradini, M.L. [Univ. of Wisconsin, Madison, WI (United States)

    1995-09-01

    The interaction of certain materials such as Al{sub 2}O{sub 3} with water results in vapor explosions with very high (supercritical) pressures and propagation velocities. A quasi-steady state analysis of supercritical detonation in one-dimensional multiphase flow was applied to analyze experimental data of the KROTOS (26-30) set of experiments conducted at the Joint Research Center at Ispra, Italy. In this work we have applied a new method of solution which allows for partial fragmentation of the fuel in the shock adiabatic thermodynamic model. This method uses known experiment values of the shock pressure and propagation velocity to estimate the initial mixing conditions of the experiment. The fuel and coolant were both considered compressible in this analysis. In KROTOS 26, 28, 29, and 30 the measured values of the shock pressure by the experiment were found to be higher than 25, 50, 100, and 100 Mpa respectively. Using the above data for the wave velocity and our best estimate for the values of the pressure, the predicted minimum values of the fragmented mass of the fuel were found to be 0.026. 0.04, 0.057, and 0.068 kg respectively. The predicted values of the work output corresponding to the above fragmented masses of the fuel were found to be 40, 84, 126, and 150 kJ respectively, with predicted initial void fractions of 112%, 12.5%, 8%, and 6% respectively.

  6. A review of vapor explosion information pertinent to the SRS reactors

    International Nuclear Information System (INIS)

    Hyder, M.L.; Allison, D.K.

    1992-04-01

    Vapor explosions are explosive events resulting from the mixing of two liquids, one of which is heated to a temperature well above the boiling point of the second. Under some circumstances mixing of the liquids can boil part of the lower boiling liquid so quickly that the expanding vapor generates a strong pressure wave and explosion. If the lower boiling liquid is water, as is frequently the case, the event is called a ''steam explosion''. Analyses in support of the K-Reactor Probabilistic Risk Assessment have shown that steam explosions generated by the interaction of molten reactor fuel with water contribute significantly to the risk of reactor operation at the SRS. This calculated risk incorporates a conservative treatment of the uncertainties associated with such explosions. Study of steam explosions involving molten reactor materials has been included in the Severe Accident Analysis Program (SAAP) in order to obtain a better evaluation of their importance, and, if possible, to find ways to avoid them. This paper presents a brief review and summary of steam explosion experience from literature accounts, along with the results of experimental studies from the SAAP. It concludes with an evaluation of current knowledge, and suggestions for future development. 71 refs

  7. Nucleation Characteristics in Physical Experiments/explosions

    International Nuclear Information System (INIS)

    Henry, R.E.; Fauske, Hans K.

    1976-01-01

    Large-scale vapor explosion experiments have shown that intimate contact between hot and cold liquids, and a temperature upon contact that is greater than the spontaneous nucleation temperature of the system, are two necessary conditions for the onset of large scale vapor explosions. A model, based on spontaneous nucleation of the homogeneous type, has been proposed to describe the relevant processes and the resulting energetics for explosive boiling systems. The model considers that spontaneous nucleation cannot occur either during the relief time for constant volume heating or until the thermal boundary layer is sufficiently thick to support a vapor cavity of the critical size. After nucleation, bubble growth does not occur until an acoustic wave establishes a pressure gradient in the cold liquid. These considerations lead to the prediction that, for a given temperature, drops greater than a critical size will remain in film boiling due to coalescence of vapor nuclei and drops smaller than this value will wet and be captured by the hot liquid surface. These results are compared to small drop data for well-wetted systems and excellent agreement is obtained between the observed behavior and the model predictions. In conclusion: A model, based on spontaneous nucleation, has been proposed to describe vaporization potential and behavior upon contact in a liquid/liquid system. This behavior is determined by the size of the liquid mass, single-phase pressurization and acoustic relief, nucleation frequency due to random density fluctuations, the initiation of unstable growth and acoustic relief, and the development of the thermal boundary layer in the cold liquid. The proposed model predicts that the stability of a given size drop upon intimate contact with another liquid is extremely dependent upon the interface temperature. For low interface temperatures, large masses will be captured by the hot liquid and the resulting vaporization rates will be extremely low because

  8. Dimensional analysis of small-scale steam explosion experiments

    International Nuclear Information System (INIS)

    Huh, K.; Corradini, M.L.

    1986-01-01

    Dimensional analysis applied to Nelson's small-scale steam explosion experiments to determine the qualitative effect of each relevant parameter for triggering a steam explosion. According to experimental results, the liquid entrapment model seems to be a consistent explanation for the steam explosion triggering mechanism. The three-dimensional oscillatory wave motion of the vapor/liquid interface is analyzed to determine the necessary conditions for local condensation and production of a coolant microjet to be entrapped in fuel. It is proposed that different contact modes between fuel and coolant may involve different initiation mechanisms of steam explosions

  9. Collapsing criteria for vapor film around solid spheres as a fundamental stage leading to vapor explosion

    International Nuclear Information System (INIS)

    Freud, Roy; Harari, Ronen; Sher, Eran

    2009-01-01

    Following a partial fuel-melting accident, a Fuel-Coolant Interaction (FCI) can result with the fragmentation of the melt into tiny droplets. A vapor film is then formed between the melt fragments and the coolant, while preventing a contact between them. Triggering, propagation and expansion typically follow the premixing stage. In the triggering stage, vapor film collapse around one or several of the fragments occurs. This collapse can be the result of fragments cooling, a sort of mechanical force, or by any other means. When the vapor film collapses and the coolant re-establishes contact with the dry surface of the hot melt, it may lead to a very rapid and rather violent boiling. In the propagation stage the shock wave front leads to stripping of the films surrounding adjacent droplets which enhance the fragmentation and the process escalates. During this process a large quantity of liquid vaporizes and its expansion can result in destructive mechanical damage to the surrounding structures. This multiphase thermal detonation in which high pressure shock wave is formed is regarded as 'vapor explosion'. The film boiling and its possible collapse is a fundamental stage leading to vapor explosion. If the interaction of the melt and the coolant does not result in a film boiling, no explosion occurs. Many studies have been devoted to determine the minimum temperature and heat flux that is required to maintain a film boiling. The present experimental study examines the minimum temperature that is required to maintain a film boiling around metal spheres immersed into a liquid (subcooled distilled water) reservoir. In order to simulate fuel fragments that are small in dimension and has mirror-like surface, small spheres coated with anti-oxidation layer were used. The heat flux from the spheres was calculated from the sphere's temperature profiles and the sphere's properties. The vapor film collapse was associated with a sharp rise of the heat flux during the cooling

  10. Safety engineering experiments of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Noboru

    1987-07-24

    The outline of large scale experiments carried out every year since 1969 to obtain fundamental data and then establish the safety engineering standards concerning the manufacturing, storage and transportation, etc. of all explosives was described. Because it becomes recently difficult to ensure the safety distance in powder magazines and powder plants, the sandwich structure with sand is thought to be suitable as the neighboring barrier walls. The special vertical structure for embankments to provide against a emergency explosion is effective to absorb the blast. Explosion behaviors such as initiating sensitivity, detonation, sympathetic detonation, and shock occurence of the ANFO explosives in place of dynamite and the slurry explosives were studied. The safety engineering standards for the manufacturing and application of explosives were studied to establish because accidents by tabacco fire are not still distinguished. Much data concerning early stage fire fighting, a large quantity of flooding and shock occurence from a assumption of ignition during machining in the propellants manufacturing plant, could be obtained. Basic studies were made to prevent pollution in blasting sites. Collected data are utilized for the safety administration after sufficient discussion. (4 figs, 2 tabs, 3 photos, 17 refs)

  11. Contained fissionly vaporized imploded fission explosive breeder reactor

    International Nuclear Information System (INIS)

    Marwick, E.F.

    1978-01-01

    Disclosed is a nuclear reactor system which produces useful thermal power and breeds fissile isotopes wherein large spherical complex slugs containing fissile and fertile isotopes as well as vaporizing and tamping materials are exploded seriatim in a large containing chamber having walls protected from the effects of the explosion by about two thousand tons of slurry of fissile and fertile isotopes in molten alkali metal. The slug which is slightly sub-critical prior to its entry into the centroid portion of the chamber, then becomes slightly more than prompt-critical because of the near proximity of neutron-reflecting atoms and of fissioning atoms within the slurry. The slurry is heated by explosion of the slugs and serves as a working fluid for extraction of heat energy from the reactor. Explosive debris is precipitated from the slurry and used for the fabrication of new slugs

  12. Boiling characteristics of dilute polymer solutions and implications for the suppression of vapor explosions

    Energy Technology Data Exchange (ETDEWEB)

    Bang, K.H.; Kim, M.H. [Univ. of Science and Technology, Pohang (Korea, Republic of)

    1995-09-01

    Quenching experiments of hot solid spheres in dilute aqueous solutions of polyethylene oxide polymer have been conducted for the purpose of investigating the physical mechanisms of the suppression of vapor explosions in this polymer solutions. Two spheres of 22.2mm and 9.5mm-diameter were tested in the polymer solutions of various concentrations at 30{degrees}C. Minimum film boiling temperature ({Delta}T{sub MFB}) in this highly-subcooled liquid rapidly decreased from over 700{degrees}c for pure water to about 150{degrees}C as the polymer concentration was increased up to 300ppm for 22.2mm sphere, and it decreased to 350{degrees}C for 9.5mm sphere. This rapid reduction of minimum film boiling temperature in the PEO aqueous solutions can explain its ability of the suppression of spontaneous vapor explosions. The ability of suppression of vapor explosions by dilute polyethylene oxide solutions against an external trigger pressure was tested by dropping molten tin into the polymer solutions at 25{degrees}C. It was observed that in 50ppm solutions more mass fragmented than in pure water, but produced weaker explosion pressures. The explosion was completely suppressed in 300ppm solutions with the external trigger. The debris size distributions of fine fragments smaller than 0.7mm were shown almost identical regardless of the polymer concentrations.

  13. Experimental study of vapor explosion of molten salt and low boiling point liquid

    International Nuclear Information System (INIS)

    Iida, Yoshihiro; Takashima, Takeo

    1987-01-01

    Fundamental study of vapor explosion using small drops of high temperature liquid and low boiling point liquid and a series of small-scale vapor explosion tests are carried out. A single or plural drops of molten LiNO 3 are dropped into ethyl alcohol and the temperature range of two liquids wherein the fragmentation occurs is examined. The propagation phenomenon of vapor explosion between two drops is photographed and the pressure trace is proved to be well consistent with the behavior of the vapor bubble regions. A small amount of molten Flinak and tin which are enclosed in a test tube is dropped into tapped water. The temperature effect of two liquids onto the occurrence of vapor explosion is investigated. Some considerations are made with respect to the upper and lower temperature limits of vapor explosion to occur. A qualitative modeling of vapor explosion mechanism is proposed and discussed. (author)

  14. Collapsing criteria for vapor film around solid spheres as a fundamental stage leading to vapor explosion

    Energy Technology Data Exchange (ETDEWEB)

    Freud, Roy [Nuclear Research Center - Negev, Beer-Sheva (Israel)], E-mail: freud@bgu.ac.il; Harari, Ronen [Nuclear Research Center - Negev, Beer-Sheva (Israel); Sher, Eran [Pearlstone Center for Aeronautical Studies, Department of Mechanical Engineering, Ben-Gurion University, Beer-Sheva (Israel)

    2009-04-15

    Following a partial fuel-melting accident, a Fuel-Coolant Interaction (FCI) can result with the fragmentation of the melt into tiny droplets. A vapor film is then formed between the melt fragments and the coolant, while preventing a contact between them. Triggering, propagation and expansion typically follow the premixing stage. In the triggering stage, vapor film collapse around one or several of the fragments occurs. This collapse can be the result of fragments cooling, a sort of mechanical force, or by any other means. When the vapor film collapses and the coolant re-establishes contact with the dry surface of the hot melt, it may lead to a very rapid and rather violent boiling. In the propagation stage the shock wave front leads to stripping of the films surrounding adjacent droplets which enhance the fragmentation and the process escalates. During this process a large quantity of liquid vaporizes and its expansion can result in destructive mechanical damage to the surrounding structures. This multiphase thermal detonation in which high pressure shock wave is formed is regarded as 'vapor explosion'. The film boiling and its possible collapse is a fundamental stage leading to vapor explosion. If the interaction of the melt and the coolant does not result in a film boiling, no explosion occurs. Many studies have been devoted to determine the minimum temperature and heat flux that is required to maintain a film boiling. The present experimental study examines the minimum temperature that is required to maintain a film boiling around metal spheres immersed into a liquid (subcooled distilled water) reservoir. In order to simulate fuel fragments that are small in dimension and has mirror-like surface, small spheres coated with anti-oxidation layer were used. The heat flux from the spheres was calculated from the sphere's temperature profiles and the sphere's properties. The vapor film collapse was associated with a sharp rise of the heat flux

  15. Numerical analysis of fragmentation mechanisms in vapor explosions

    Energy Technology Data Exchange (ETDEWEB)

    Koshizuka, Seiichi; Ikeda, Hirokazu; Oka, Yoshiaki [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

    1998-01-01

    Fragmentation of molten metal is the key process in vapor explosions. However this process is so rapid that the mechanisms have not been clarified yet in the experimental studies. Besides, numerical simulation is difficult because we have to analyze water, steam and molten metal simultaneously with evaporation and fragmentation. The authors have been developing a new numerical method, the Moving Particle Semi-implicit (MPS) method, based on moving particles and their interactions. Grids are not necessary. Incompressible flows with fragmentation on free surfaces have been calculated successfully using the MPS method. In the present study numerical simulation of the fragmentation processes using the MPS method is carried out to investigate the mechanisms. A numerical model to calculate evaporation from water to steam is developed. In this model, new particles are generated on water-steam interfaces. Effect of evaporation is also investigated. Growth of the filament is not accelerated when the normal evaporation is considered. This is because the normal evaporation needs a longer time than the moment of the jet impingement, though the filament growth is decided in this moment. Next, rapid evaporation based on spontaneous nucleation is considered. The filament growth is markedly accelerated. This result is consistent with the experimental fact that the spontaneous nucleation temperature is a necessary condition of small-scale vapor explosions. (J.P.N.)

  16. Studies on formation of unconfined detonable vapor cloud using explosive means.

    Science.gov (United States)

    Apparao, A; Rao, C R; Tewari, S P

    2013-06-15

    Certain organic liquid fuels like hydrocarbons, hydrocarbon oxides, when dispersed in air in the form of small droplets, mix with surrounding atmosphere forming vapor cloud (aerosol) and acquire explosive properties. This paper describes the studies on establishment of conditions for dispersion of fuels in air using explosive means resulting in formation of detonable aerosols of propylene oxide and ethylene oxide. Burster charges based on different explosives were evaluated for the capability to disperse the fuels without causing ignition. Parameters like design of canister, burster tube, burster charge type, etc. have been studied based on dispersion experiments. The detonability of the aerosol formed by the optimized burster charge system was also tested. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Safety assessment of in-vessel vapor explosion loads in next generation reactor

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Kwang Hyun; Cho, Jong Rae; Choi, Byung Uk; Kim, Ki Yong; Lee, Kyung Jung [Korea Maritime University, Busan (Korea); Park, Ik Kyu [Seoul National University, Seoul (Korea)

    1998-12-01

    A safety assessment of the reactor vessel lower head integrity under in-vessel vapor explosion loads has been performed. The premixing and explosion calculations were performed using TRACER-II code. Using the calculated explosion pressures imposed on the lower head inner wall, strain calculations were performed using ANSYS code. The explosion analyses show that the explosion impulses are not altered significantly by the uncertain parameters of triggering location and time, fuel and vapor volume fractions in uniform premixture bounding calculations within the conservative ranges. Strain analyses using the calculated pressure loads on the lower head inner wall show that the vapor explosion-induced lower head failure is physically unreasonable. The static analysis using the conservative explosion-end pressure of 7,246 psia shows that the maximum equivalent strain is 4.3% at the bottom of lower head, which is less than the allowable threshold value of 11%. (author). 24 refs., 40 figs., 3 tabs.

  18. The effect of binary oxide materials on a single droplet vapor explosion triggering

    International Nuclear Information System (INIS)

    Hansson, R.C.; Manickam, L.T.; Dinh, T.N.

    2011-01-01

    In order to explore the fundamental mechanism dictated by the material influence on triggering, fine fragmentation and subsequent vapor explosion energetics, a series of experiments using a mixture of eutectic and non-eutectic binary oxide were initiated. Dynamics of the hot liquid (WO 3 -CaO) droplet and the volatile liquid (water) were investigated in the MISTEE (Micro-Interactions in Steam Explosion Experiments) facility by performing well-controlled, externally triggered, single-droplet experiments, using a high-speed visualization system with synchronized digital cinematography and continuous X-ray radiography, called SHARP (Simultaneous High-speed Acquisition of X-ray Radiography and Photography). The acquired images followed by further analysis showed a milder interaction for the non-eutectic melt composition for the tests with low melt superheat, whether no evident differences between eutectic and non-eutectic melt compositions regarding bubble dynamics, energetics and melt preconditioning was perceived for the high melt superheat tests. (author)

  19. TRACER-II: a complete computational model for mixing and propagation of vapor explosions

    Energy Technology Data Exchange (ETDEWEB)

    Bang, K.H. [School of Mechanical Engineering, Korea Maritime Univ., Pusan (Korea, Republic of); Park, I.G.; Park, G.C.

    1998-01-01

    A vapor explosion is a physical process in which very rapid energy transfer occurs between a hot liquid and a volatile, colder liquid when the two liquids come into a sudden contact. For the analyses of potential impacts from such explosive events, a computer program, TRACER-II, has been developed, which contains a complete description of mixing and propagation phases of vapor explosions. The model consists of fuel, fragmented fuel (debris), coolant liquid, and coolant vapor in two-dimensional Eulerian coordinates. The set of governing equations are solved numerically using finite difference method. The results of this numerical simulation of vapor explosions are discussed in comparison with the recent experimental data of FARO and KROTOS tests. When compared to some selected FARO and KROTOS data, the fuel-coolant mixing and explosion propagation behavior agree reasonably with the data, although the results are yet sensitive primarily to the melt breakup and fragmentation modeling. (author)

  20. The numerical methods for the development of the mixture region in the vapor explosion simulations

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Y.; Ohashi, H.; Akiyama, M. [Univ. of Tokyo (Japan)

    1995-09-01

    An attempt to numerically simulate the process of the vapor explosion with a general multi-component and multi-dimension code is being challenged. Because of the rapid change of the flow field and extremely nonuniform distribution of the components in the system of the vapor explosion, the numerical divergence and diffusion are subject to occur easily. A dispersed component model and a multiregion scheme, by which these difficulties can be effectively overcome, were proposed. The simulations have been performed for the processes of the premixing and the fragmentation propagation in the vapor explosion.

  1. Formation of microbeads during vapor explosions of Field's metal in water

    KAUST Repository

    Kouraytem, Nadia; Li, Erqiang; Thoroddsen, Sigurdur T

    2016-01-01

    We use high-speed video imaging to investigate vapor explosions during the impact of a molten Field's metal drop onto a pool of water. These explosions occur for temperatures above the Leidenfrost temperature and are observed to occur in up to three stages as the metal temperature is increased, with each explosion being more powerful that the preceding one. The Field's metal drop breaks up into numerous microbeads with an exponential size distribution, in contrast to tin droplets where the vapor explosion deforms the metal to form porous solid structures. We compare the characteristic bead size to the wavelength of the fastest growing mode of the Rayleigh-Taylor instability.

  2. Vortex-Induced Vapor Explosion during Drop Impact on a Superheated Pool

    KAUST Repository

    Alchalabi, M.A.; Kouraytem, Nadia; Li, Erqiang; Thoroddsen, Sigurdur T

    2017-01-01

    Ultra high-speed imaging is used to investigate the vapor explosion when a drop impacts onto a high-temperature pool. The two liquids are immiscible, a low boiling-temperature perfluorohexane drop, at room temperature, which impacts a high boiling-temperature soybean-oil pool, which is heated well above the boiling temperature of the drop. We observe different regimes: weak and strong nucleate boiling, film boiling or Leidenfrost regime and entrainment followed by vapor explosion. The vapor explosions were seen to depend on the formation of a rotational flow at the edge of the impact crater, near the pool surface, which resembles a vortex ring. This rotational motion entrains a thin sheet of the drop liquid, to become surrounded by the oil. In that region, the vapor explosion starts at a point after which it propagates azimuthally along the entire periphery at high speed.

  3. Vortex-Induced Vapor Explosion during Drop Impact on a Superheated Pool

    KAUST Repository

    Alchalabi, M.A.

    2017-04-18

    Ultra high-speed imaging is used to investigate the vapor explosion when a drop impacts onto a high-temperature pool. The two liquids are immiscible, a low boiling-temperature perfluorohexane drop, at room temperature, which impacts a high boiling-temperature soybean-oil pool, which is heated well above the boiling temperature of the drop. We observe different regimes: weak and strong nucleate boiling, film boiling or Leidenfrost regime and entrainment followed by vapor explosion. The vapor explosions were seen to depend on the formation of a rotational flow at the edge of the impact crater, near the pool surface, which resembles a vortex ring. This rotational motion entrains a thin sheet of the drop liquid, to become surrounded by the oil. In that region, the vapor explosion starts at a point after which it propagates azimuthally along the entire periphery at high speed.

  4. An Experimental Study on the Dynamics of a Single Droplet Vapor Explosion

    International Nuclear Information System (INIS)

    Concilio Hansson, Roberta

    2010-01-01

    The present study aims to develop a mechanistic understanding of the thermal-hydraulic processes in a vapor explosion, which may occur in nuclear power plants during a hypothetical severe accident involving interactions of high-temperature corium melt and volatile coolant. Over the past several decades, a large body of literature has been accumulated on vapor explosion phenomenology and methods for assessment of the related risk. Vapor explosion is driven by a rapid fragmentation of high temperature melt droplets, leading to a substantial increase of heat transfer areas and subsequent explosive evaporation of the volatile coolant. Constrained by the liquid-phase coolant, the rapid vapor production in the interaction zone causes pressurization and dynamic loading on surrounding structures. While such a general understanding has been established, the triggering mechanism and subsequent dynamic fine fragmentation have yet not been clearly understood. A few mechanistic fragmentation models have been proposed, however, computational efforts to simulate the phenomena generated a large scatter of results. Dynamics of the hot liquid (melt) droplet and the volatile liquid (coolant) are investigated in the MISTEE (Micro-Interactions in Steam Explosion Experiments) facility by performing well-controlled, externally triggered, single-droplet experiments, using a high-speed visualization system with synchronized digital cinematography and continuous X-ray radiography, called SHARP (Simultaneous High-speed Acquisition of X-ray Radiography and Photography). After an elaborate image processing, the SHARP images depict the evolution of both melt material (dispersal) and coolant (bubble dynamics), and their microscale interactions, i.e. the triggering phenomenology. The images point to coolant entrainment into the droplet surface as the mechanism for direct contact/mixing ultimately responsible for energetic interactions. Most importantly, the MISTEE data reveals an inverse

  5. An Experimental Study on the Dynamics of a Single Droplet Vapor Explosion

    Energy Technology Data Exchange (ETDEWEB)

    Concilio Hansson, Roberta

    2010-07-01

    The present study aims to develop a mechanistic understanding of the thermal-hydraulic processes in a vapor explosion, which may occur in nuclear power plants during a hypothetical severe accident involving interactions of high-temperature corium melt and volatile coolant. Over the past several decades, a large body of literature has been accumulated on vapor explosion phenomenology and methods for assessment of the related risk. Vapor explosion is driven by a rapid fragmentation of high temperature melt droplets, leading to a substantial increase of heat transfer areas and subsequent explosive evaporation of the volatile coolant. Constrained by the liquid-phase coolant, the rapid vapor production in the interaction zone causes pressurization and dynamic loading on surrounding structures. While such a general understanding has been established, the triggering mechanism and subsequent dynamic fine fragmentation have yet not been clearly understood. A few mechanistic fragmentation models have been proposed, however, computational efforts to simulate the phenomena generated a large scatter of results. Dynamics of the hot liquid (melt) droplet and the volatile liquid (coolant) are investigated in the MISTEE (Micro-Interactions in Steam Explosion Experiments) facility by performing well-controlled, externally triggered, single-droplet experiments, using a high-speed visualization system with synchronized digital cinematography and continuous X-ray radiography, called SHARP (Simultaneous High-speed Acquisition of X-ray Radiography and Photography). After an elaborate image processing, the SHARP images depict the evolution of both melt material (dispersal) and coolant (bubble dynamics), and their microscale interactions, i.e. the triggering phenomenology. The images point to coolant entrainment into the droplet surface as the mechanism for direct contact/mixing ultimately responsible for energetic interactions. Most importantly, the MISTEE data reveals an inverse

  6. Mass Spectrometry Vapor Analysis for Improving Explosives Detection Canine Proficiency

    Science.gov (United States)

    2017-02-10

    Explosives are typically encoun- tered as hidden or wrapped in a packaged material. The in- strument was used to determine an odor exfiltration point...from a packaged explosive. A sample of C4 wrapped in plastic was analyzed by monitoring cyclohexanone. Signal was observed to increase whenever...explosives. This method makes intuitive sense because handlers cannot see odors, so their intention is used as a surrogate for whether or not an

  7. Vapor explosion studies for nuclear and non-nuclear industries

    Energy Technology Data Exchange (ETDEWEB)

    Taleyarkhan, Rusi P. [Arden L. Bement, Jr. Professor Nuclear Engineering, School of Nuclear Engineering, 1290 Nuclear Engineering Building, Room 108C, Purdue University, West Lafayette, IN 47905 (United States)]. E-mail: rusi@purdue.edu

    2005-05-01

    Energetic melt-water explosions are a well-established contributor to risk for nuclear reactors, and even more so for the metal casting industry. In-depth studies were undertaken in an industry-national laboratory collaborative effort to understand the root causes of explosion triggering and to evaluate methods for prevention. The steam explosion triggering studies (SETS) facility was devised and implemented for deriving key insights into explosion prevention. Data obtained indicated that onset of base surface-entrapment induced explosive boiling-caused trigger shocks is a result of complex combination of surface wettability, type of coating (organic versus inorganic), degree of coating wearoff, existence of bypass pathways for pressure relief, charring and non-condensable gas (NCG) release potential. Of these parameters NCGs were found to play a preeminent role on explosion prevention by stabilizing the melt-water steam interface and acting as a shock absorber. The role of NCGs was experimentally confirmed using SETS for their effect on stable film boiling using a downward facing heated body through which gases were injected. The presence of NCGs in the steam film layer caused a significant delay in the transitioning of film-to-nucleate boiling. The role of NCGs on explosion prevention was thereafter demonstrated more directly by introducing molten metal drops into water pools with and without NCG bubbling. Whereas spontaneous and energetic explosions took place without NCG injection, only benign quenching occurred in the presence of NCGs. Gravimetric analyses of organic coatings which are known to prevent explosion onset were also found to release significant NCGs during thermal attack by melt in the presence of water. These findings offer a novel, simple, cost-effective technique for deriving fundamental insights into melt-water explosions as well as for explosion prevention under most conditions of interest to metal casting, and possibly for nuclear reactor

  8. The role of fragmentation mechanism in large-scale vapor explosions

    International Nuclear Information System (INIS)

    Liu, Jie

    2003-01-01

    A non-equilibrium, multi-phase, multi-component code PROVER-I is developed for propagation phase of vapor explosion. Two fragmentation models are used. The hydrodynamic fragmentation model is the same as Fletcher's one. A new thermal fragmentation model is proposed with three kinds of time scale for modeling instant fragmentation, spontaneous nucleation fragmentation and normal boiling fragmentation. The role of fragmentation mechanisms is investigated by the simulations of the pressure wave propagation and energy conversion ratio of ex-vessel vapor explosion. The spontaneous nucleation fragmentation results in a much higher pressure peak and a larger energy conversion ratio than hydrodynamic fragmentation. The instant fragmentation gives a slightly larger energy conversion ratio than spontaneous nucleation fragmentation, and the normal boiling fragmentation results in a smaller energy conversion ratio. The detailed analysis of the structure of pressure wave makes it clear that thermal detonation exists only under the thermal fragmentation circumstance. The high energy conversion ratio is obtained in a small vapor volume fraction. However, in larger vapor volume fraction conditions, the vapor explosion is weak. In a large-scale vapor explosion, the hydrodynamic fragmentation is essential when the pressure wave becomes strong, so a small energy conversion ratio is expected. (author)

  9. A study of the effect of binary oxide materials in a single droplet vapor explosion

    Energy Technology Data Exchange (ETDEWEB)

    Hansson, R.C., E-mail: rch@kth.se [Royal Institute of Technology, Stockholm (Sweden); Dinh, T.N.; Manickam, L.T. [Royal Institute of Technology, Stockholm (Sweden)

    2013-11-15

    In an effort to explore fundamental mechanisms that may govern the effect of melt material on vapor explosion's triggering, fine fragmentation and energetics, a series of experiments using a binary-oxide mixture with eutectic and non-eutectic compositions were performed. Interactions of a hot liquid (WO{sub 3}–CaO) droplet and a volatile liquid (water) were investigated in well-controlled, externally triggered, single-droplet experiments conducted in the Micro-interactions in steam explosion experiments (MISTEE) facility. The tests were visualized by means of a synchronized digital cinematography and continuous X-ray radiography system, called simultaneous high-speed acquisition of X-ray radiography and photography (SHARP). The acquired images followed by further analysis indicate milder interactions for the droplet with non-eutectic melt composition in the tests with low melt superheat, whereas no evident differences between eutectic and non-eutectic melt compositions regarding bubble dynamics, energetics and melt preconditioning was observed in the tests with higher melt superheat.

  10. A study of the effect of binary oxide materials in a single droplet vapor explosion

    International Nuclear Information System (INIS)

    Hansson, R.C.; Dinh, T.N.; Manickam, L.T.

    2013-01-01

    In an effort to explore fundamental mechanisms that may govern the effect of melt material on vapor explosion's triggering, fine fragmentation and energetics, a series of experiments using a binary-oxide mixture with eutectic and non-eutectic compositions were performed. Interactions of a hot liquid (WO 3 –CaO) droplet and a volatile liquid (water) were investigated in well-controlled, externally triggered, single-droplet experiments conducted in the Micro-interactions in steam explosion experiments (MISTEE) facility. The tests were visualized by means of a synchronized digital cinematography and continuous X-ray radiography system, called simultaneous high-speed acquisition of X-ray radiography and photography (SHARP). The acquired images followed by further analysis indicate milder interactions for the droplet with non-eutectic melt composition in the tests with low melt superheat, whereas no evident differences between eutectic and non-eutectic melt compositions regarding bubble dynamics, energetics and melt preconditioning was observed in the tests with higher melt superheat

  11. The effect of binary oxide materials on a single droplet vapor explosion triggering

    Energy Technology Data Exchange (ETDEWEB)

    Hansson, R.C.; Manickam, L.T.; Dinh, T.N. [Royal Inst. of Tech., Stockholm (Sweden)

    2011-07-01

    In order to explore the fundamental mechanism dictated by the material influence on triggering, fine fragmentation and subsequent vapor explosion energetics, a series of experiments using a mixture of eutectic and non-eutectic binary oxide were initiated. Dynamics of the hot liquid (WO{sub 3}-CaO) droplet and the volatile liquid (water) were investigated in the MISTEE (Micro-Interactions in Steam Explosion Experiments) facility by performing well-controlled, externally triggered, single-droplet experiments, using a high-speed visualization system with synchronized digital cinematography and continuous X-ray radiography, called SHARP (Simultaneous High-speed Acquisition of X-ray Radiography and Photography). The acquired images followed by further analysis showed a milder interaction for the non-eutectic melt composition for the tests with low melt superheat, whether no evident differences between eutectic and non-eutectic melt compositions regarding bubble dynamics, energetics and melt preconditioning was perceived for the high melt superheat tests. (author)

  12. Formation of microbeads during vapor explosions of Field's metal in water

    KAUST Repository

    Kouraytem, Nadia

    2016-06-17

    We use high-speed video imaging to investigate vapor explosions during the impact of a molten Field\\'s metal drop onto a pool of water. These explosions occur for temperatures above the Leidenfrost temperature and are observed to occur in up to three stages as the metal temperature is increased, with each explosion being more powerful that the preceding one. The Field\\'s metal drop breaks up into numerous microbeads with an exponential size distribution, in contrast to tin droplets where the vapor explosion deforms the metal to form porous solid structures. We compare the characteristic bead size to the wavelength of the fastest growing mode of the Rayleigh-Taylor instability.

  13. A Lithium Vapor Box Divertor Similarity Experiment

    Science.gov (United States)

    Cohen, Robert A.; Emdee, Eric D.; Goldston, Robert J.; Jaworski, Michael A.; Schwartz, Jacob A.

    2017-10-01

    A lithium vapor box divertor offers an alternate means of managing the extreme power density of divertor plasmas by leveraging gaseous lithium to volumetrically extract power. The vapor box divertor is a baffled slot with liquid lithium coated walls held at temperatures which increase toward the divertor floor. The resulting vapor pressure differential drives gaseous lithium from hotter chambers into cooler ones, where the lithium condenses and returns. A similarity experiment was devised to investigate the advantages offered by a vapor box divertor design. We discuss the design, construction, and early findings of the vapor box divertor experiment including vapor can construction, power transfer calculations, joint integrity tests, and thermocouple data logging. Heat redistribution of an incident plasma-based heat flux from a typical linear plasma device is also presented. This work supported by DOE Contract No. DE-AC02-09CH11466 and The Princeton Environmental Institute.

  14. Conditions of external loading of nuclear power plant structures by vapor cloud explosions and design requirements

    International Nuclear Information System (INIS)

    Geiger, W.

    1977-01-01

    In the design of nuclear power plant structures in the Federal Republic of Germany (FRG) the external loading by pressure waves from unconfined vapor cloud explosions is taken into account. The loading conditions used are based on simplified model considerations for the sequence of events which generates the pressure wave. The basic assumption is that the explosion of unconfined vapor clouds can evolve only in the form of a deflagration wave with a maximum overpressure of 0.3 bar. The research on gas explosions conducted in the FRG with a view to external reactor safety just as similar work in other countries demonstrates that there are still various problems which need further clarification. The principal issues are the maximum conceivable load and the modes of structrual response. This paper presents the main results of a status report commissioned by the German Ministry of the Inertior in which the whole sequence of events leading to the external loading of nuclear power plants and the corresponding response of the structure was scrutinized. Constitutive in establishing the status report have been thorough discussions with experts of the various fields. The following problem areas are discussed in the paper. Incidents leading to the release of large amounts of liquefied gas; Formation of explosive vapor clouds, ignition conditions; Development of the explosion, generation of the pressure wave; Interaction between pressure wave and reactor building. It is outlined where definite statements are possible and where uncertainties and information gaps exist. (Auth.)

  15. Experiences of marijuana-vaporizer users.

    Science.gov (United States)

    Malouff, John M; Rooke, Sally E; Copeland, Jan

    2014-01-01

    Using a marijuana vaporizer may have potential harm-reduction advantages on smoking marijuana, in that the user does not inhale smoke. Little research has been published on use of vaporizers. In the first study of individuals using a vaporizer on their own initiative, 96 adults anonymously answered questions about their experiences with a vaporizer and their use of marijuana with tobacco. Users identified 4 advantages to using a vaporizer over smoking marijuana: perceived health benefits, better taste, no smoke smell, and more effect from the same amount of marijuana. Users identified 2 disadvantages: inconvenience of setup and cleaning and the time it takes to get the device operating for each use. Only 2 individuals combined tobacco in the vaporizer mix, whereas 15 combined tobacco with marijuana when they smoked marijuana. Almost all participants intended to continue using a vaporizer. Vaporizers seem to have appeal to marijuana users, who perceive them as having harm-reduction and other benefits. Vaporizers are worthy of experimental research evaluating health-related effects of using them.

  16. Underwater electrical wire explosion: Shock wave from melting being overtaken by shock wave from vaporization

    Science.gov (United States)

    Li, Liuxia; Qian, Dun; Zou, Xiaobing; Wang, Xinxin

    2018-05-01

    The shock waves generated by an underwater electrical wire explosion were investigated. A microsecond time-scale pulsed current source was used to trigger the electrical explosion of copper wires with a length of 5 cm and a diameter of 200 μm. The energy-storage capacitor was charged to a relatively low energy so that the energy deposited onto the wire was not large enough to fully vaporize the whole wire. Two shock waves were recorded with a piezoelectric gauge that was located at a position of 100 mm from the exploding wire. The first and weak shock wave was confirmed to be the contribution from wire melting, while the second and stronger shock wave was the contribution from wire vaporization. The phenomenon whereby the first shock wave generated by melting being overtaken by the shock wave due to vaporization was observed.

  17. Explosive Infrasonic Events: Sensor Comparison Experiment (SCE)

    Energy Technology Data Exchange (ETDEWEB)

    Schnurr, J. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Garces, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rodgers, A. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-02-06

    SCE (sensor comparison experiment) 1 through 4 consists of a series of four controlled above-ground explosions designed to provide new data for overpressure propagation. Infrasound data were collected by LLNL iPhones and other sensors. Origin times, locations HOB, and yields are not being released at this time and are therefore not included in this report. This preliminary report will be updated as access to additional data changes, or instrument responses are determined.

  18. Suppression of Vapor Explosions in a Water-Molten-Tin System by Augmentation of the Void Fraction

    International Nuclear Information System (INIS)

    Meeks, Michael K.; Baker, Michael C.; Bonazza, Riccardo

    2000-01-01

    Experiments were performed to determine the likelihood of a vapor explosion when injecting an inert gas (nitrogen) and a coolant (water) into a pool of molten metal (tin) in a large-scale chamber (∼20 kg fuel). The injection flow rates of the water and nitrogen gas were the principal experimental variables, with average water flow rates up to 0.05 x 10 -3 m 3 /s and gas flow rates ranging from 0.33 x 10 -3 to 1.67 x 10 -3 m 3 /s. Of 35 successful experiments, 11 resulted in an explosive interaction, as determined by audible signals, videotape, and accelerometer data. The main objective of the investigation was to determine the existence of a boundary between explosive and nonexplosive regions in the water-gas flow rate plane: Such a boundary was indeed identified and approximated by a straight line. Two experiments in which explosive interactions were obtained in the low water/gas flow regions after a relatively long time of coolant injection (∼5 to 10 s) demonstrate the hitherto undervalued importance of the temporal variable

  19. Air blast effects on nuclear power plants from vapor cloud explosions

    International Nuclear Information System (INIS)

    Wiedermann, A.H.; Eichler, T.V.; Kot, C.A.

    1981-01-01

    To assess the hazards arising from the explosion of a large flammable vapor cloud a method was developed for estimating the air blast field assuming a detonation wave is established. The actual 'pancake' like geometry typical for negatively buoyant vapor clouds is taken into account. The cloud height and other characteristics are generated by a global cloud dynamics model for negatively buoyant clouds. This model provides the cloud height as a function of fuel vapor concentration and other pertinent variables. A two-dimensional Eulerian shock hydrodynamic computer code is utilized to compute the blast environment in the neighborhood of the end of the cloud. The initial field is taken to be a quasi-steady explosion field calculated by the method of characteristics for a thin Prandtl-Meyer expansion wave, and the upward driven air shock representing the combustion and pressure relief processes inherent in the pancake geometry. This initial fields is established in the 2-D hydrocode at a time corresponding to the arrival of the detonation front at the cloud edge. It is to be noted that the local blast environment scales with respect to the cloud height. The computational results indicate that it is essential to include the influence of cloud geometry for the realistic prediction of the air blast hazard arising from the explosion of a negatively buoyant vapor cloud. (orig./HP)

  20. Explosive performance on the non-proliferation experiment

    Energy Technology Data Exchange (ETDEWEB)

    McKown, T.O. [Los Alamos National Lab., NM (United States)

    1994-12-31

    The Explosive Effects Physics Project at the Los Alamos National Laboratory planned and conducted experiments on the Non-Proliferation Experiment (NPE) as part of its effort to define source functions for seismic waves. Since all investigations were contingent on the performance of the emplaced chemical explosive, an array of diagnostic measurements was fielded in the emplaced explosive. The CORRTEX (COntinuous Reflectometry for Radius vs Time EXperiment) system was used to investigate the explosive initiation and to determine the detonation velocities on three levels and in a number of radial directions. The CORRTEX experiments fielded in the explosive chamber will be described, including a description of the explosive emplacement from the perspective of its impact on the CORRTEX results. The data obtained are reviewed and the resulting detonation velocities are reported. A variation of detonation velocity with depth in the explosive and the apparent underdetonation and overdetonation of the explosive in different radial directions is reported.

  1. Multichannel Discriminative Detection of Explosive Vapors with an Array of Nanofibrous Membranes Loaded with Quantum Dots

    Directory of Open Access Journals (Sweden)

    Zhaofeng Wu

    2017-11-01

    Full Text Available The multichannel fluorescent sensor array based on nanofibrous membranes loaded with ZnS quantum dots (QDs was created and demonstrated for the discriminative detection of explosives. The synergistic effect of the high surface-to-volume ratio of QDs, the good permeability of nanofibrous membranes and the differential response introduced by surface ligands was played by constructing the sensing array using nanofibrous membranes loaded with ZnS QDs featuring several surface ligands. Interestingly, although the fluorescence quenching of the nanofibrous membranes is not linearly related to the exposure time, the fingerprint of each explosive at different times is very similar in shape, and the fingerprints of the three explosives show different shapes. Three saturated vapors of nitroaromatic explosives could be reliably detected and discriminated by the array at room temperature. This work is the first step toward devising a monitoring system for explosives in the field of public security and defense. It could, for example, be coupled with the technology of image recognition and large data analysis for a rapid diagnostic test of explosives. This work further highlights the power of differential, multichannel arrays for the rapid and discriminative detection of a wide range of chemicals.

  2. Modeling a High Explosive Cylinder Experiment

    Science.gov (United States)

    Zocher, Marvin A.

    2017-06-01

    Cylindrical assemblies constructed from high explosives encased in an inert confining material are often used in experiments aimed at calibrating and validating continuum level models for the so-called equation of state (constitutive model for the spherical part of the Cauchy tensor). Such is the case in the work to be discussed here. In particular, work will be described involving the modeling of a series of experiments involving PBX-9501 encased in a copper cylinder. The objective of the work is to test and perhaps refine a set of phenomenological parameters for the Wescott-Stewart-Davis reactive burn model. The focus of this talk will be on modeling the experiments, which turned out to be non-trivial. The modeling is conducted using ALE methodology.

  3. Triggering and Energetics of a Single Drop Vapor Explosion: The Role of Entrapped Non-Condensable Gases

    Energy Technology Data Exchange (ETDEWEB)

    Hansson, Roberta Concilio [Royal Institute of Technology, Stockholm (Sweden)

    2009-11-15

    The present work pertains to a research program to study Molten Fuel-Coolant Interactions (MFCI), which may occur in a nuclear power plant during a hypothetical severe accident. Dynamics of the hot liquid (melt) droplet and the volatile liquid (coolant) were investigated in the MISTEE (Micro-Interactions in Steam Explosion Experiments) facility by performing well-controlled, externally triggered, single-droplet experiments, using a high-speed visualization system with synchronized digital cinematography and continuous X-ray radiography. The current study is concerned with the MISTEE-NCG test campaign, in which a considerable amount of non-condensable gases (NCG) are present in the film that enfolds the molten droplet. The SHARP images for the MISTEE-NCG tests were analyzed and special attention was given to the morphology (aspect ratio) and dynamics of the air/ vapor bubble, as well as the melt drop preconditioning. Energetics of the vapor explosion (conversion ratio) were also evaluated. The MISTEE.NCG tests showed two main aspects when compared to the MISTEE test series (without entrapped air). First, analysis showed that the melt preconditioning still strongly depends on the coolant subcooling. Second, in respect to the energetics, the tests consistently showed a reduced conversion ratio compared to that of the MISTEE test series

  4. Investigation of vapor explosions with alumina droplets in sodium

    International Nuclear Information System (INIS)

    Zimmer, H.J.

    1991-02-01

    Within the analysis of severe hypothetical fast breeder accidents the consequence of a fuel-coolant interaction has to be considered i.e. the thermal interaction between hot molten fuel and sodium. Experiments have been performed to study the thermal fragmentation of a molten alumina droplet in sodium. Alumina temperatures up to 3100 K and sodium temperatures up to 1143 K were used. For the first time film boiling of alumina drops in sodium was achieved. With some droplets undergoing film boiling, the fragmentation was triggered by an externally applied pressure wave. The trigger was followed promptly by a strong reaction pressure wave if and only if a contact temperature threshold of T I =2060±160 K was exceeded. In agreement with similar experiments in which other materials were studied this threshold corresponds to an interfacial temperature close to the homogeneous nucleation temperature of the vaporising liquid. Based on the present and previous experimental results a model concept of thermal fragmentation is developed. (orig.) [de

  5. Methodology for the experimental research of vapor explosion

    International Nuclear Information System (INIS)

    Dmitriy I Borisenko; Yanhua Yang

    2005-01-01

    The method for experimental definition of influence of speed of fuel's surface increase at FCI is proposed. by modeling a fuel fragmentation for a case of falling of fuel compact weight on a coolant free surface with the help of the dumped heated up capsule opening under a level of a coolant free surface. Basic scheme of capsule is submitted in figure (the scheme of Dumped Opening Capsule (DOC)). Before beginning experiment through apertures in a covering 3 and a body of a case 4 in a hollow, limited to a case and the cylinder 6, spheres of small diameter have been incorporated. The total area of a surface of spheres is much more than area of external superficial of capsule. DOC is heated up to necessary temperature and it is fallen down in cooling a liquid. The principle work of DOC consists in the following. The plate 8, amazing about a free surface of a coolant, presses a pusher of 11 internal DOC. A pusher moving - relative DOC on axes of symmetry a teeth of compression of 'dog' 14. Being narrowed, teeth 'dogs' stop to hold a glass 7 installations bottom part of a case 5. At action of spring 13 parts of a case 4 and 5 moved separately on an axis of symmetry DOC and are enclosed in spheres adjoin to a coolant. (authors)

  6. Experimental study on vapor explosion induced by pressure pulse in coarse mixing of hot molten metal and water

    International Nuclear Information System (INIS)

    Inoue, A.; Tobita, Y.; Aritomi, M.; Takahashi, M.; Matsuzaki, M.

    2004-01-01

    An experimental study was done to investigate characteristics of metal-water interaction, when a mount of hot liquid metal is injected into the water. The test section is a vertical shock tube of 60mm in inner diameter and 1200mm in length. A special injector which is designed to inject hot metal of controlled volume and flow rate is attached at the top of the tube. When the hot metal is injected in the water and comes down at a position of the test vessel, a trigger pressure pulse is generated at the bottom of the test tube. Local transient pressures along the tube are measured by piezo pressure transducers. The following items were investigated in the experiment; 1) The criteria to cause a vapor explosion, 2) Transient behaviors and propagation characteristics of pressure wave in the mixing region. 3) Effects of triggering pulse, injection temperature and mass of hot molten metal on the peak pressure. The probability of the vapor explosion jumped when the interface temperature at the molten metal-water direct contact is higher than the homogeneous nucleation temperature of water and the triggering pulse becomes larger than 0.9MPa. Two types of the pressure propagation modes are observed, one is the detonative mode with a sharp rise and other is usual pressure mode with a mild rise. (author)

  7. Hydrodynamics of Explosion Experiments and Models

    CERN Document Server

    Kedrinskii, Valery K

    2005-01-01

    Hydronamics of Explosion presents the research results for the problems of underwater explosions and contains a detailed analysis of the structure and the parameters of the wave fields generated by explosions of cord and spiral charges, a description of the formation mechanisms for a wide range of cumulative flows at underwater explosions near the free surface, and the relevant mathematical models. Shock-wave transformation in bubbly liquids, shock-wave amplification due to collision and focusing, and the formation of bubble detonation waves in reactive bubbly liquids are studied in detail. Particular emphasis is placed on the investigation of wave processes in cavitating liquids, which incorporates the concepts of the strength of real liquids containing natural microinhomogeneities, the relaxation of tensile stress, and the cavitation fracture of a liquid as the inversion of its two-phase state under impulsive (explosive) loading. The problems are classed among essentially nonlinear processes that occur unde...

  8. Modeling the fine fragmentation following the triggering stage of a vapor explosion

    International Nuclear Information System (INIS)

    Darbord, I.

    1997-01-01

    In the frame of PWR severe accidents, where the core melt, this thesis studies one of the stages of an FCI (fuel coolant interaction) or vapor explosion. An FCI is a rapid evaporation of a coolant when it comes into contact with a hot liquid. More precisely, the subject of this study is the triggering stage of the FCI, when a fuel drop of diameter around one centimeter breaks up into many fragments, diameter of which is around a hundred micrometers. The model describes the cyclic collapse and growth of a vapor bubble around the fuel droplet and its fragmentation. The main features of the model are: - the destabilization of the film or the vapor bubble due to the growth of Rayleigh-Taylor instabilities (those form coolant jets that contact the fuel surface); - The mechanisms of fragmentation, following the contacts (in the case of entrapment of a certain amount of coolant in the fuel, the entrapped coolant evaporates violently after it has been heated to the homogeneous nucleation temperature); - the transient heat transfer from the fragments to the coolant and the elevated vapor production, which leads to an important expansion of the bubble (about this point, the cooling of the fragments has been described by a transient heat transfer coefficient linked to nucleate boiling). The results of the model show good agreement with experimental data. (Author)

  9. Weapons Experiments Division Explosives Operations Overview

    Energy Technology Data Exchange (ETDEWEB)

    Laintz, Kenneth E. [Los Alamos National Laboratory

    2012-06-19

    Presentation covers WX Division programmatic operations with a focus on JOWOG-9 interests. A brief look at DARHT is followed by a high level overview of explosives research activities currently being conducted within in the experimental groups of WX-Division. Presentation covers more emphasis of activities and facilities at TA-9 as these efforts have been more traditionally aligned with ongoing collaborative explosive exchanges covered under JOWOG-9.

  10. ALPHA visual data collection. STX005-025: melt drop steam explosion experiments

    International Nuclear Information System (INIS)

    Moriyama, Kiyofumi; Yamano, Norihiro; Maruyama, Yu; Kudo, Tamotsu; Sugimoto, Jun

    1999-03-01

    Steam explosion is a phenomenon in which a high temperature liquid gives its internal energy to a low temperature volatile liquid extremely quickly causing rapid evaporation and shock wave generation. In the field of nuclear reactor safety research regarding severe accidents in LWRs, steam explosions involving molten fuel and coolant has been recognized as a potential threat to the integrity of the reactor containment vessel. In the ALPHA (Assessment of Loads and Performance of Containment in Hypothetical Accident) program, experiments were performed to investigate the phenomenology of vapor explosions using iron-alumina thermite melt as a simulant of molten core. This report collects the experimental results especially emphasizing the visual observations by high speed photography. (author)

  11. Analysis of KROTOS KS-2 and KS-4 steam explosion experiments with TEXAS-VI

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ronghua, E-mail: rhchen@mail.xjtu.edu.cn [State Key Laboratory of Multiphase Flow in Power Engineering, School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Wang, Jun [Nuclear Engineering and Engineering Physics, College of Engineering, University of Wisconsin Madison, WI 53706 (United States); Su, G.H.; Qiu, Suizheng [State Key Laboratory of Multiphase Flow in Power Engineering, School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Corradini, M.L., E-mail: Corradini@engr.wisc.edu [Nuclear Engineering and Engineering Physics, College of Engineering, University of Wisconsin Madison, WI 53706 (United States)

    2016-12-01

    Highlights: • The KS-2 and KS-4 steam explosion experiments were analyzed by TEXAS-VI. • The coarse mixing status up to the explosion triggering time was well predicted by TEXAS-VI. • The predicted dynamic explosion pressure was in good agreement with the experimental results. - Abstract: TEXAS-VI is a transient, three-field, one-dimensional mechanistic model for the steam explosion phenomena. A fuel solidification model and associated fragmentation criteria of the solidifying particle for both the mixing phase and explosion phase were developed and incorporated into TEXAS-VI to account for solidification. In the present study, TEXAS-VI was used to analyze the KS-2 and KS-4 steam explosion experiments, which were performed in the KROTOS facility as part of the OECD-SERENA-2 program. In the simulation, the KROTOS experimental facility was modeled as Eulerian control volumes based on the facility geometry. The molten corium jet was divided up into a series of LaGrangian master particles equal to the initial jet diameter. Both the mixing phase and the explosion phase of the experiments were simulated by TEXAS-VI. Comparison to test data indicates that the fuel jet kinematics and the vapor volume during the mixing phase were well predicted by TEXAS-VI. The TEXAS-VI prediction of the dynamic explosion pressure at different axial locations in the test was also in good agreement with the experimental results. The maximum pressure of KS-2 and KS-4 predicted by TEXAS-VI were 16.7 MPa and 41.9 MPa, respectively. The KS-4 maximum steam explosion pressure predicted by TEXAS-VI was higher than that of KS-2, which was consistent with experiment observation. The observed differences of the dynamic explosion pressure between the KS-2 and KS-4 experiments were also successfully simulated by TEXAS-VI. This suggests that TEXAS-VI is able to analyze the effect of prototypic melt compositions on the steam explosion phenomena. Additional benchmarking and evaluations are ongoing.

  12. Explosive performance on the non-proliferation experiment

    Energy Technology Data Exchange (ETDEWEB)

    McKown, T.O.

    1994-03-01

    The non-proliferation experiment, originally called the chemical kiloton experiment, was planned and executed by Lawrence Livermore National Laboratory to investigate the seismic yield relationship and distinguishing seismic signals between a nuclear event and a large mass conventional explosion. The Los Alamos National Laboratory planned and conducted experiments to further their studies of the source function for signals observed seismically. Since all investigations were contingent on the performance of the emplaced chemical explosive, an array of diagnostic measurements was fielded in the emplaced explosive. The CORRTEX system was used to investigate the explosive initiation and to determine the detonation velocities in multiple levels and in numerous directions. A description of the CORRTEX experiments fielded, a review of the data obtained and some interpretations of the data are reported.

  13. Laser induced explosive vapor and cavitation resulting in effective irrigation of the root canal. Part 1: a visualization study

    NARCIS (Netherlands)

    Blanken, J.; de Moor, R.J.G.; Meire, M.; Verdaasdonk, R.

    2009-01-01

    Background and Objectives: Limited information exists regarding the induction of explosive vapor and cavitation bubbles in an endodontic rinsing solution. It is also not clear whether a fiber has to be moved in the irrigation solution or can be kept stationary. No information is available on safe

  14. Laser Induced Explosive Vapor and Cavitation Resulting in Effective Irrigation of the Root Canal. Part 1 : A Visualization Study

    NARCIS (Netherlands)

    Blanken, Jan; De Moor, Roeland Jozef Gentil; Meire, Maarten; Verdaasdonk, Rudolf

    Background and Objectives: Limited information exists regarding the induction of explosive vapor and cavitation bubbles in an endodontic rinsing solution. It is also not clear whether a fiber has to be moved in the irrigation solution or can be kept stationary. No information is available on safe

  15. Soviet experience with peaceful uses of nuclear explosions

    International Nuclear Information System (INIS)

    Nordyke, M.D.

    1976-01-01

    The Soviet Union is pursuing an active program for developing peaceful uses of nuclear explosions (PNE). They have reported 16 explosions, with applications ranging from putting out oil-well fires and stimulating oil recovery to creating instant dams and canals. The data reported generally agree with U.S. experience. Seismic data collected by western sources on explosions outside the known Soviet test sites indicate that the Soviet program is at least twice as large as they have reported. The accelerated pace of these events suggests that in some applications the Soviet PNE program is approaching routine industrial technology

  16. Research on the fundamental process of thermal-hydraulic behaviors in severe accident. Estimation of trigger condition for vapor explosion. JAERI's nuclear research promotion program, H10-027-1. Contract research

    International Nuclear Information System (INIS)

    Nariai, Hideki

    2002-03-01

    The experimental and analytical researches were conducted to study melted core material and coolant interaction including solidification and vapor explosion which is one of the most unidentified thermal hydraulic phenomena during sever accident of nuclear reactor. At first, the effect of the material properties on vapor explosion and solidification was examined to clarify the dominant factors for the spontaneous vapor explosion. Next, the interfacial phenomena of the high temperature melt material and violent boiling behavior of water at the interface was visually observed in the experiment. The interfacial phenomena were physically modeled. Finally, trigger phenomena from liquid-liquid contact to atomization were clarified through the forced collapse experiment of vapor film around a molten droplet by using pressure wave generation device. It is indicated by applying the results obtained in the present study to the actual reactor conditions that the possibility of the vapor explosion is extremely unlikely in the actual reactor accident sequence, since the surface of the molten uranium oxide is solidified in the water and the liquid-liquid contact can not be achieved. It should be noted that the decrease of the solidified temperature by metal compounds and the increase of the molten core temperature. (author)

  17. Research on the fundamental process of thermal-hydraulic behaviors in severe accident. Estimation of trigger condition for vapor explosion. JAERI's nuclear research promotion program, H10-027-1. Contract research

    Energy Technology Data Exchange (ETDEWEB)

    Nariai, Hideki [Tsukuba Univ., Institute of Engineering Mechanics and Systems, Tsukuba, Ibaraki (Japan)

    2002-03-01

    The experimental and analytical researches were conducted to study melted core material and coolant interaction including solidification and vapor explosion which is one of the most unidentified thermal hydraulic phenomena during sever accident of nuclear reactor. At first, the effect of the material properties on vapor explosion and solidification was examined to clarify the dominant factors for the spontaneous vapor explosion. Next, the interfacial phenomena of the high temperature melt material and violent boiling behavior of water at the interface was visually observed in the experiment. The interfacial phenomena were physically modeled. Finally, trigger phenomena from liquid-liquid contact to atomization were clarified through the forced collapse experiment of vapor film around a molten droplet by using pressure wave generation device. It is indicated by applying the results obtained in the present study to the actual reactor conditions that the possibility of the vapor explosion is extremely unlikely in the actual reactor accident sequence, since the surface of the molten uranium oxide is solidified in the water and the liquid-liquid contact can not be achieved. It should be noted that the decrease of the solidified temperature by metal compounds and the increase of the molten core temperature. (author)

  18. A Simple Experiment for Determining Vapor Pressure and Enthalpy of Vaporization of Water.

    Science.gov (United States)

    Levinson, Gerald S.

    1982-01-01

    Laboratory procedures, calculations, and sample results are described for a freshman chemistry experiment in which the Clausius-Clapeyron equation is introduced as a means of describing the variation of vapor pressure with temperature and for determining enthalpy of vaporization. (Author/SK)

  19. A demonstration experiment for studying the properties of saturated vapor

    Science.gov (United States)

    Grebenev, Igor V.; Lebedeva, Olga V.; Polushkina, Svetlana V.

    2017-11-01

    The paper proposes an important demonstration experiment that can be used at secondary schools in physics. The described experiment helps students learn the main concepts of the topic ‘saturated vapor’, namely, evaporation, condensation, dynamic equilibrium, saturation vapor, partial pressure, and the dependence of saturated vapor pressure on temperature.

  20. Comparing CTH simulations and experiments on explosively loaded rings

    Science.gov (United States)

    Braithwaite, C. H.; Aydelotte, Brady; Collins, Adam; Thadhani, Naresh; Williamson, David Martin

    2012-03-01

    A series of experiments were conducted on explosively loaded metallic rings for the purpose of studying fragmentation. In addition to the collection of fragments for analysis, the radial velocity of the expanding ring was measured with photon Doppler velocimetry (PDV) and the arrangement was imaged using high speed photography. Both the ring material and the material used as the explosive container were altered and the results compared with simulations performed in CTH. Good agreement was found between the simulations and the experiments. The maximum radial velocity attained was approximately 380 m/s, which was achieved through loading with a 5g PETN based charge.

  1. Explosive vaporization induced by high-power CO2-laser target interactions

    International Nuclear Information System (INIS)

    Hugenschmidt, M.; Vollrath, K.

    1976-01-01

    The interactions of high-power laser pulses with targets such as metals or dielectric materials causes a series of optical, thermal, and mechanical processes. Thereby, heating, melting, and vaporization can take place in a short time. At power densities of about 10 7 to several 10 8 W/cm 2 this can even be produced explosively. As compared to continuous ablation, this type of interaction can remove greater masses from the bulk of material. The investigations are performed by using an electron-beam preionized CO 2 -laser acting on different target materials. The energy of the laser pulses is about 30 J, the pulse-half-widths of the long-tail pulses 4 to 6 μs. Optical measurements yield some information on threshold values for these processes, for the formation and expansion of plasmas, and for the ejection of material in form of greater particles. High speed photographic techniques include a rotating mirror- and an image converter camera. Starting from shock-wave theory, gas dynamic equations (in unidimensional approximation) allow for a quantitative determination of the specific internal energies and pressures in the case of optical detonation. (orig.) [de

  2. Simulation of first SERENA KROTOS steam explosion experiment

    International Nuclear Information System (INIS)

    Leskovar, Matjaz; Ursic, Mitja

    2009-01-01

    A steam explosion may occur when, during a severe reactor accident, the molten core comes into contact with the coolant water. A strong enough steam explosion in a nuclear power plant could jeopardize the containment integrity and so lead to a direct release of radioactive material to the environment. To resolve the open issues in steam explosion understanding and modeling, the OECD program SERENA Phase 2 was launched at the end of year 2007, focusing on nuclear applications. SERENA comprises an experimental program, which is being carried out in the complementary KROTOS and TROI corium facilities, accompanied by a comprehensive analytical program, where also pre- and post-test calculations are foreseen. In the paper the sensitivity post-test calculations of the first SERENA KROTOS experiment KS-1, which were performed with the code MC3D, are presented and discussed. Since the results of the SERENA tests are restricted to SERENA members, only the various calculation results are given, not comparing them to experimental measurements. Various premixing and explosion simulations were performed on a coarse and a fine numerical mesh, applying two different jet breakup models (global, local) and varying the minimum bubble diameter in the explosion simulations (0.5 mm, 5 mm). The simulations revealed that all varied parameters have a significant influence on the calculation results, as was expected since the fuel coolant interaction process is a highly complex phenomenon. The results of the various calculations are presented in comparison and the observed differences are discussed and explained. (author)

  3. Laser induced explosive vapor and cavitation resulting in effective irrigation of the root canal. Part 1: a visualization study.

    Science.gov (United States)

    Blanken, Jan; De Moor, Roeland Jozef Gentil; Meire, Maarten; Verdaasdonk, Rudolf

    2009-09-01

    Limited information exists regarding the induction of explosive vapor and cavitation bubbles in an endodontic rinsing solution. It is also not clear whether a fiber has to be moved in the irrigation solution or can be kept stationary. No information is available on safe power settings for the use of cavitation in the root canal. This study investigates the fluid movements and the mechanism of action caused by an Er,Cr:YSGG laser in a transparent root model. Glass models with an artificial root canal (15 mm long, with a 0.06 taper and apical diameter of 400 microm) were used for visualization and registration with a high-speed imaging technique (resolution in the microsecond range) of the creation of explosive vapor bubbles with an Er,Cr:YSGG laser at pulse energies of 75, 125, and 250 mJ at 20 Hz using a 200 microm fiber (Z2 Endolase). Fluid movement was investigated by means of dyes and visualization of the explosive vapor bubbles, and as a function of pulse energy and distance of the fiber tip to the apex. The recordings in the glass model show the creation of expanding and imploding vapor bubbles with secondary cavitation effects. Dye is flushed out of the canal and replaced by surrounding fluid. It seems not necessary to move the fiber close to the apex. Imaging suggests that the working mechanism of an Er,Cr:YSGG laser in root canal treatment in an irrigation solution can be attributed to cavitation effects inducing high-speed fluid motion into and out the canal.

  4. Unconfined deflagrative explosions without turbulence: experiments and model

    International Nuclear Information System (INIS)

    Lannoy, A.

    1989-01-01

    This paper reviews laboratory, balloon and open field experiments which have been performed to study the deflagration regime in free air. In a first part, are considered different models available to estimate deflagrative unconfined explosions effects, without turbulence. Then, a description is given of the known performed tests, which indicate the effective scale of various experiments, their operating conditions and the type of measurements carried out. Results are presented and discussed. The influence on the explosion force of different parameters (fuel concentration gradients, flammable mixture shape and size, ignition energy) is estimated. The overall conclusion of this survey is that flammable mixtures drifting over open field and ignited, will burn with low flame speed and consequently will generate very weak pressure effects [fr

  5. Shot H3837: Darht's First Dual-Axis Explosive Experiment

    Science.gov (United States)

    Mendez, Jacob; McNeil, Wendy Vogan; Harsh, James; Hull, Lawrence

    2011-06-01

    Test H3837 was the first explosive shot performed in front of both flash x-ray axes at the Los Alamos Dual Axis Radiographic HydroTest (DARHT) facility. Executed in November 2009, the shot was an explosively-driven metal flyer plate in a series of experiments designed to explore equation-of-state properties of shocked materials. Imaging the initial shock wave traveling through the flyer plate, DARHT Axis II captured the range of motion from the shock front emergence in the flyer to breakout at the free surface; the Axis I pulse provided a perpendicular perspective of the shot at a time coinciding with the third pulse of Axis II. Since the days of the Manhattan Project, penetrating radiography with multiple frames from different viewing angles has remained a high-profile goal at the Laboratory. H3837 is merely the beginning of a bright future for two-axis penetrating radiography.

  6. First vapor explosion calculations performed with MC3D thermal-hydraulic code

    Energy Technology Data Exchange (ETDEWEB)

    Brayer, C.; Berthoud, G. [CEA Centre d`Etudes de Grenoble, 38 (France). Direction des Reacteurs Nucleaires

    1998-01-01

    This paper presents the first calculations performed with the `explosion` module of the multiphase computer code MC3D, which is devoted to the fine fragmentation and explosion phase of a fuel coolant interaction. A complete description of the physical laws included in this module is given. The fragmentation models, taking into account two fragmentation mechanisms, a thermal one and an hydrodynamic one, are also developed here. Results to some calculations to test the numerical behavior of MC3D and to test the explosion models in 1D or 2D are also presented. (author)

  7. Evaluation of hand-held ion-mobility explosives vapor detectors

    International Nuclear Information System (INIS)

    Burrows, T.A.; Thoma, P.J.

    1979-12-01

    Two types of ion-mobility detectors were evaluated in both laboratory and field tests. Laboratory test results show that these detectors are highly sensitive to dynamite and pistol powder and have good false-alarm agent rejection. Field tests of these two detectors revealed that they would detect dynamite and Ball-C-Propellent in free air. However, neither of the ion-mobility detectors would detect these explosives if the explosives were concealed

  8. Advancing Explosion Source Theory through Experimentation: Results from Seismic Experiments Since the Moratorium on Nuclear Testing

    Science.gov (United States)

    Bonner, J. L.; Stump, B. W.

    2011-12-01

    On 23 September 1992, the United States conducted the nuclear explosion DIVIDER at the Nevada Test Site (NTS). It would become the last US nuclear test when a moratorium ended testing the following month. Many of the theoretical explosion seismic models used today were developed from observations of hundreds of nuclear tests at NTS and around the world. Since the moratorium, researchers have turned to chemical explosions as a possible surrogate for continued nuclear explosion research. This talk reviews experiments since the moratorium that have used chemical explosions to advance explosion source models. The 1993 Non-Proliferation Experiment examined single-point, fully contained chemical-nuclear equivalence by detonating over a kiloton of chemical explosive at NTS in close proximity to previous nuclear explosion tests. When compared with data from these nearby nuclear explosions, the regional and near-source seismic data were found to be essentially identical after accounting for different yield scaling factors for chemical and nuclear explosions. The relationship between contained chemical explosions and large production mining shots was studied at the Black Thunder coal mine in Wyoming in 1995. The research led to an improved source model for delay-fired mining explosions and a better understanding of mining explosion detection by the International Monitoring System (IMS). The effect of depth was examined in a 1997 Kazakhstan Depth of Burial experiment. Researchers used local and regional seismic observations to conclude that the dominant mechanism for enhanced regional shear waves was local Rg scattering. Travel-time calibration for the IMS was the focus of the 1999 Dead Sea Experiment where a 10-ton shot was recorded as far away as 5000 km. The Arizona Source Phenomenology Experiments provided a comparison of fully- and partially-contained chemical shots with mining explosions, thus quantifying the reduction in seismic amplitudes associated with partial

  9. Enthalpy of Vaporization by Gas Chromatography: A Physical Chemistry Experiment

    Science.gov (United States)

    Ellison, Herbert R.

    2005-01-01

    An experiment is conducted to measure the enthalpy of vaporization of volatile compounds like methylene chloride, carbon tetrachloride, and others by using gas chromatography. This physical property was measured using a very tiny quantity of sample revealing that it is possible to measure the enthalpies of two or more compounds at the same time.

  10. An effect of corium composition variations on occurrence of a steam explosion in the TROI experiments

    International Nuclear Information System (INIS)

    Kim, J. W.; Park, I. K.; Hong, S. W.; Min, B. T.; Shin, Y. S.; Song, J. H.; Kim, H. D.

    2003-01-01

    Recently series of steam explosion experiments have been performed in the TROI facility using corium melts of various compositions. The compositions (UO 2 : ZrO 2 ) of the corium were 0 : 100, 50 : 50, 70 : 30, 80 : 20 and 87 : 13 in weight percent and the mass of the corium was about 10kg. An experiment using 0 : 100 corium (pure zirconia) caused a steam explosion. An experiment using 50 : 50 corium did not cause a steam explosion while a steam spike occurred in an experiment using 70 : 30 corium which was the eutectic point of corium. A steam spike is considered to be the fact that a triggering of a steam explosion occurred but a propagation process does not occur so as to cause a weak interaction. However, the possibility of a steam explosion with this composition can not be ruled out since many steam explosions occurred in the previous experiments. In the two experiments using 80 : 20 corium, a steam spike occurred in one experiment but no steam explosion occurred in the other experiment. However, the triggerability of a steam explosion with this composition is not clear since few steam explosions occurred in the previous experiments. And no steam explosion occurred in an experiment using 87 : 13 corium of which urania content was the greatest among the experiments performed in the TROI facility. From this, the possibility of a steam explosion or a steam spike is appeared to be high in the non-mush zone. It is considered that an explosive interaction could easily occur with the eutectic composition. Since the solidification temperature around the eutectic point is low, the melt is likely to maintain its liquid state at the time of triggering so as to cause an explosive phenomenon

  11. The preliminary results of steam explosion experiments in TROI

    International Nuclear Information System (INIS)

    Song, J.H.; Park, I.K.; Chang, Y.J.; Min, B.T.; Hong, S.W.; Kim, H.D.

    2001-01-01

    Korea Atomic Energy Research Institute (KAERI) launched an intermediate scale steam explosion experiment named 'Test for Real corium Interaction with water (TROI)' using reactor material to investigate the effect of material composition, multi-dimensional melt-water interaction, and hydrogen generation. The melt-water interaction is confined in a pressure vessel with the multi-dimensional fuel and water pool geometry. The cold crucible technology, where the mixture of oxide powder in a water-cooled cage is heated by high frequency induction, is employed. It minimizes unwanted inclusion of impurities during the melting process. The data acquisition system and instrumentations which measure the static and dynamic pressure, temperatures of melt and water are set up. In the first series of tests using several kg of ZrO 2 , melt water interaction is made in a heated water pool at 95 Celsius degrees without triggering. A steam spike pressure at about 10 bar is observed. The morphology of debris shows that there was a mild local steam explosion. The melt water interaction was monitored by video cameras. The UO 2 tests are scheduled around March of 2001, in parallel with the improvements of the design of test facility. (authors)

  12. Electronic Vapor Cigarette Battery Explosion Causing Shotgun-like Superficial Wounds and Contusion

    Directory of Open Access Journals (Sweden)

    Siri Shastry, MD

    2016-03-01

    Full Text Available INTRODUCTION Electronic vapor cigarettes (E-cigarettes were created in 2003 as an alternative to traditional tobacco cigarettes. E-cigarettes have been available in the United States since 2006.1 The typical E-cigarette consists of a cartridge that contains liquid, an atomizer that heats the liquid (i.e. acts as a vaporizer, as well as a battery. The liquid contained within the cartridge contains nicotine, propylene glycol and/ or glycerol as well as flavorings. The consumer uses an E-cigarette through either pushing a button or inhalation, which triggers heating and therefore aerosolizes the liquid within the cartridge, emulating cigarette “smoke.” The newest E-cigarettes are larger than nicotine cigarettes and employ stronger, rechargeable batteries as a power source.2,3

  13. Background on the commercial explosive chosen for the non-proliferation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mammele, M.E.

    1994-12-31

    The requirements of the Chemical Kiloton Experiment as outlined in the original explosives bid package provided DYNO NOBEL/Alpha-Ireco, Inc. with a unique challenge. The size of the chamber, the total volume of explosives required, the chemical energy equivalent of one kiloton, the time-frame of loading the chamber, transportation, safety, were all necessary considerations in choosing this particular explosive. The rationale for choosing this particular emulsion/ANFO blend of blasting agent explosive will be presented. DYNO NOBEL INC in-house theoretical predictions as to the explosive performance potential of the blasting agent will be compared to some of the actual data acquired upon detonation. The results of this type of experiment may provide new insight as to the efficiency of the energy release of typical commercial explosives.

  14. Gas explosion characterization, wave propagation (small-scale experiments)

    International Nuclear Information System (INIS)

    Larsen, G.C.

    1985-01-01

    A number of experiments have been performed with blast waves arising from the ignition of homogeneous and well defined mixtures of methane, oxygen and nitrogen, contained within spherical balloons with controlled initial dimensions. In the initial small scale experiments pressure characteristics, ground reflection phenomena and pressure distribution on box like obstacles were studied. Both configurations with one box and two closely spaced boxes have been considered, and a wave-wave interaction phenomenom was observed in the case of closely spaced obstacles. Main emphasis has been placed on the half scale field experiments. In these, the maximum flame speed has been of the order of 100 m/s, resulting in positive peak pressures of 50-100.10 2 Pa in 5 - 10 m distance from the source. The explosion process was found to be reasonable symmetric. The attenuation of the blast wave due to vegetation and the influence of obstacles as banks, walls and houses on the pressure field have been investigated. The presence of the bank and the house was felt in a zone with a length corresponding to a typical dimension of the obstacles, whereas the overall pressure field is shown to be unaffected by the type of obstacles and vegetation investigated. For the wall and house, reflection factors have been established, and some variation over the surface has been measured. The scatter of the pressure measurements is estimated for stable, neutral and unstable atmospheric conditions, and an attempt to determine the ground reflection factor has been performed. Finally the accelerations of a house exposed to the blast wave have been examined

  15. Multiparametric Experiments and Multiparametric Setups for Metering Explosive Eruptions

    Science.gov (United States)

    Taddeucci, J.; Scarlato, P.; Del Bello, E.

    2016-12-01

    Explosive eruptions are multifaceted processes best studied by integrating a variety of observational perspectives. This need marries well with the continuous stream of new means that technological progress provides to volcanologists to parameterize these eruptions. Since decades, new technologies have been tested and integrated approaches have been attempted during so-called multiparametric experiments, i.e., short field campaigns with many, different instruments (and scientists) targeting natural laboratory volcanoes. Recently, portable multiparametric setups have been developed, including a few, highly complementary instruments to be rapidly deployed at any erupting volcano. Multiparametric experiments and setups share most of their challenges, like technical issues, site logistics, and data processing and interpretation. Our FAMoUS (FAst MUltiparametric Setup) setup pivots around coupled, high-speed imaging (visible and thermal) and acoustic (infrasonic to audible) recording, plus occasional seismic recording and sample collection. FAMoUS provided new insights on pyroclasts ejection and settling and jet noise dynamics at volcanoes worldwide. In the last years we conducted a series of BAcIO (Broadband ACquisition and Imaging Operation) experiments at Stromboli (Italy). These hosted state-of-the-art and prototypal eruption-metering technologies, including: multiple high-speed high-definition cameras for 3-D imaging; combined visible-infrared-ultraviolet imaging; in-situ and remote gas measurements; UAV aerial surveys; Doppler radar, and microphone arrays. This combined approach provides new understandings of the fundamental controls of Strombolian-style activity, and allows for crucial cross-validation of instruments and techniques. Several documentary expeditions participated in the BAcIO, attesting its tremendous potential for public outreach. Finally, sharing field work promotes interdisciplinary discussions and cooperation like nothing in the world.

  16. Boiling liquid expanded vapor explosion (BLEVE) of petroleum storage and transportation facilities case study Khartoum State

    International Nuclear Information System (INIS)

    Elatabani, E. G. M.

    2010-06-01

    The objective of this study includes the identification of possible causes of fires and explosions resulting from liquefied petroleum gases in Khartoum state, method of raising the awareness and knowledge of risks resulting from them, in addition to the proposal of safety precautions in the event of such incidents. The study was conducted in highly populated Khartoum state. It was in that context, the compilation and analysis of information on fire statistics was carried based on data collected through field studies and records of the civil defense - Administrative of Khartoum state, during period between (2007 - 2009). The procedure followed include statistical analysis of the collected data using program (e-views) method of estimation of least squares (LS). The obtained results of this method is negative sign and the percentage of house fires represent 98% from other type of fires (petroleum service stations - LPG tankers). These results, revealed that most of those fires were due to leakage of gas in residential houses attributed to lack of awareness of possible dangers and underestimation of safety precautions compared to those taken in to consideration in petroleum service stations and during transportation phases. The main recommendation of this study is to strengthen means of raising public awareness of dangers caused by liquefied petroleum gases fire through special media programs and training of workers in the field of civil defense and the empowerment of safety procedures. (Author)

  17. Preliminary experiment research of explosively driven opening switch

    International Nuclear Information System (INIS)

    Li Xiaolin; Chen Dongqun; Li Da; Cao Shengguang; Chen Yingcong

    2010-01-01

    In pulse power technology field, many loads require high current pulse with fast risetime, but sometimes, the common high current pulse powers don't satisfy request, thus there need pulse erection switches of sorts to shorten pulse risetime. Explosively driven opening switch (EDOS) is a good choice, it has simple structure and excellent performance, the primary parameters of EDOS are opening time, opening resistance, opening current and dissipation energy, which determine its performance and range for applications. For this, two kinds of EDOS are designed and manufactured, in the later experiments, the power supply is a 200 μF capacitor and the conductor is 0.03 mm copper foil, the results indicate that the two kinds of EDOS have good performance, the opening time is about 1-3 μs, the opening resistance is about 1-2 Ω, the opening current is about 24-31 kA and the average dissipation energy is about 0.125-0.34 kJ per groove, the capability of conduction current is adjusted by the thickness of conductor along with different opening current. (authors)

  18. Rock Springs Site 12 hydraulic/explosive true in situ oil shale fracturing experiment

    Energy Technology Data Exchange (ETDEWEB)

    Parrish, R.L.; Boade, R.R.; Stevens, A.L.; Long, A. Jr.; Turner, T.F.

    1980-06-01

    The experiment plan involved the creation and characterization of three horizontal hydraulic fractures, followed by the insertion and simultaneous detonation of slurry explosive in the two lower fractures. Core analyses, wellbore logging, and airflow and /sup 85/Kr tracer tests were used for site characterization and assessment of the hydraulic and explosive fracturing. Tiltmeters, wellhead pressure and flow gages, and in-formation pressure, flow and crack-opening sensors were used to monitor hydrofracture creation and explosive insertion. Explosive detonation diagnostic data were taken with stress and time-of-arrival gages and surface and in-formation accelerometers. The post-fracturing assessments indicated that: (1) hydrofracture creation and explosive insertion and detonation were accomplished essentially as planned; (2) induced fractures were randomly distributed through the shale with no extensively fractured regions or dislocation of shale; and (3) enhancement of permeability was limited to enlargement of the explosive-filled fractures.

  19. Water vapor permeabilities through polymers: diffusivities from experiments and simulations

    International Nuclear Information System (INIS)

    Seethamraju, Sindhu; Ramamurthy, Praveen Chandrashekarapura; Madras, Giridhar

    2014-01-01

    This study experimentally determines water vapor permeabilities, which are subsequently correlated with the diffusivities obtained from simulations. Molecular dynamics (MD) simulations were used for determining the diffusion of water vapor in various polymeric systems such as polyethylene, polypropylene, poly (vinyl alcohol), poly (vinyl acetate), poly (vinyl butyral), poly (vinylidene chloride), poly (vinyl chloride) and poly (methyl methacrylate). Cavity ring down spectroscopy (CRDS) based methodology has been used to determine the water vapor transmission rates. These values were then used to calculate the diffusion coefficients for water vapor through these polymers. A comparative analysis is provided for diffusivities calculated from CRDS and MD based results by correlating the free volumes. (paper)

  20. Modeling the fine fragmentation following the triggering stage of a vapor explosion; Modelisation de la fragmentaton fine lors de la phase de declenchement d`une explosion de vapeur

    Energy Technology Data Exchange (ETDEWEB)

    Darbord, I [CEA Grenoble, 38 (France). Service d` Etudes et de Modelisation Thermohydraulique

    1997-06-11

    In the frame of PWR severe accidents, where the core melt, this thesis studies one of the stages of an FCI (fuel coolant interaction) or vapor explosion. An FCI is a rapid evaporation of a coolant when it comes into contact with a hot liquid. More precisely, the subject of this study is the triggering stage of the FCI, when a fuel drop of diameter around one centimeter breaks up into many fragments, diameter of which is around a hundred micrometers. The model describes the cyclic collapse and growth of a vapor bubble around the fuel droplet and its fragmentation. The main features of the model are: - the destabilization of the film or the vapor bubble due to the growth of Rayleigh-Taylor instabilities (those form coolant jets that contact the fuel surface); - The mechanisms of fragmentation, following the contacts (in the case of entrapment of a certain amount of coolant in the fuel, the entrapped coolant evaporates violently after it has been heated to the homogeneous nucleation temperature); - the transient heat transfer from the fragments to the coolant and the elevated vapor production, which leads to an important expansion of the bubble (about this point, the cooling of the fragments has been described by a transient heat transfer coefficient linked to nucleate boiling). The results of the model show good agreement with experimental data. (Author) 68 refs.

  1. Research Performance Progress Report: Diverging Supernova Explosion Experiments on NIF

    Energy Technology Data Exchange (ETDEWEB)

    Plewa, Tomasz [Florida State Univ., Tallahassee, FL (United States)

    2016-10-25

    The aim of this project was to design a series of blast-wave driven Rayleigh-Taylor (RT) experiments on the National Ignition Facility (NIF). The experiments of this kind are relevant to mixing in core-collapse supernovae (ccSNe) and have the potential to address previously unanswered questions in high-energy density physics (HEDP) and astrophysics. The unmatched laser power of the NIF laser offers a unique chance to observe and study “new physics” like the mass extensions observed in HEDP RT experiments performed on the Omega laser [1], which might be linked to self-generated magnetic fields [2] and so far could not be reproduced by numerical simulations. Moreover, NIF is currently the only facility that offers the possibility to execute a diverging RT experiment, which would allow to observe processes such as inter-shell penetration via turbulent mixing and shock-proximity effects (distortion of the shock by RT spikes).

  2. Suppression of stratified explosive interactions

    Energy Technology Data Exchange (ETDEWEB)

    Meeks, M.K.; Shamoun, B.I.; Bonazza, R.; Corradini, M.L. [Wisconsin Univ., Madison, WI (United States). Dept. of Nuclear Engineering and Engineering Physics

    1998-01-01

    Stratified Fuel-Coolant Interaction (FCI) experiments with Refrigerant-134a and water were performed in a large-scale system. Air was uniformly injected into the coolant pool to establish a pre-existing void which could suppress the explosion. Two competing effects due to the variation of the air flow rate seem to influence the intensity of the explosion in this geometrical configuration. At low flow rates, although the injected air increases the void fraction, the concurrent agitation and mixing increases the intensity of the interaction. At higher flow rates, the increase in void fraction tends to attenuate the propagated pressure wave generated by the explosion. Experimental results show a complete suppression of the vapor explosion at high rates of air injection, corresponding to an average void fraction of larger than 30%. (author)

  3. Vapor-phase biofiltration: Laboratory and field experience

    International Nuclear Information System (INIS)

    Evans, P.J.; Bourbonais, K.A.; Peterson, L.E.; Lee, J.H.; Laakso, G.L.

    1995-01-01

    Application of vapor-phase bioreactors (VPBs) to petroleum hydrocarbons is complicated by the different mass transfer characteristics of aliphatics and aromatics. Laboratory- and pilot-scale VPB studies were conducted to evaluate treatment of soil vapor extraction (SVE) off-gas. A mixture of compost, perlite, and activated carbon was the selected medium based on pressure drop, microbial colonization, and adsorption properties. Two different pilot-scale reactors were built with a difference of 70:1 in scale. The smaller VPB's maximum effective elimination capacity (EC) was determined to be 7.2 g m -3 h -1 ; the larger unit's EC was 70% to 80% of this value. Low EC values may be attributable to a combination of mass-transfer and kinetic limitations

  4. Vaporizing Flow in Hot Fractures: Observations from Laboratory Experiments

    International Nuclear Information System (INIS)

    Kneafsey, T.; Pruess, K.

    1998-01-01

    Understanding water seepage in hot fractured rock is important in a number of fields including geothermal energy recovery and nuclear waste disposal. Heat-generating high-level nuclear waste packages which will be emplaced in the partially saturated fractured tuffs at the potential high-level nuclear waste repository at Yucca Mountain, Nevada, if it becomes a high-level nuclear waste repository, will cause significant impacts on moisture distribution and migration. Liquid water, which occupies anywhere from 30 to 100% of the porespace, will be vaporized as the temperature reaches the boiling temperature. Flowing primarily in fractures, the vapor will condense where it encounters cooler rock, generating mobile water. This water will flow under gravitational and capillary forces and may flow back to the vicinity of the emplaced waste where it may partially escape vaporization. Water flowing down (sub-) vertical fractures may migrate considerable distances through fractured rock that is at above-boiling temperatures; thus, flowing condensate may contact waste packages, and provide a pathway for the transport of water-soluble radionuclides downward to the saturated zone. Thermally-driven flow processes induced by repository heat may be as important or even more important for repository performance than natural infiltration. For a nominal thermal loading of 57 kW/acre, vaporization may generate an average equivalent percolation flux from condensate of 23.1 mm/yr over 1,000 years, and 5.2 mm/yr over 10,000 years. These numbers are comparable to or larger than current estimates of net infiltration at Yucca Mountain. This condensate, which is generated in the immediate vicinity (meters) of the waste packages, will likely have a larger impact on waste package and repository performance than a similar amount of water introduced at the land surface

  5. Theoretical investigations on the fragmentation of drops of melt with respect to the description of thermal detonations (vapor explosions) and their application in the code Frademo

    International Nuclear Information System (INIS)

    Burger, M.; Carachalios, C.; Kim, D.S.; Unger, H.

    1986-01-01

    Vapor explosions caused by the contact of molten core material with coolant are an important issue within reactor safety analysis, because they could produce an early threat to the containment during a core melt accident. The case of steady-state propagation of a detonation wave through a coarse premixture of melt and coolant represents the most severe case of a large scale vapor explosion under reactor conditions with the highest rate and largest heat release and therefore also the highest yield of mechanical energy. The present contribution starts with the description of the integral model of the detonation wave. The fragmentation processes, which are decisive for these exchange terms and the detonation process as a whole, are dealt with also. Hydrodynamic fragmentation processes as well as a thermally induced one are considered. The processes which take place inside a detonation wave, especially the fragmentation of the drops of melt and the velocity equilibration between the melt and the coolant, determine the behavior of the wave. In the present model these processes are described within a three-phase approach, considering the drops of melt, the fragments and the coolant as separate flow phases. In the frame of this work, the computer code FRADEMO has been developed. It consists of an overall description of the processes inside a steady-state detonation wave in combination with a full description of the detailed models on hydrodynamic and thermal fragmentation presented in this report. Some useful information for the potential code user is given in the appendix of the detailed report also

  6. Gas explosion characterization, wave propagation (small scale experiments)

    International Nuclear Information System (INIS)

    Larsen, G.C.

    1985-08-01

    A number of experiments have been performed with blast waves arising from the ignition of homogeneous and well defined mixtures of methane, oxygen and nitrogen, contained within spherical balloons with controlled initial dimensions. The pressure characteristics has been studied for blast waves with and without influence from reflected waves. The influence of obstacles in the flow field has also been treated. Both configuration with one box and two closely spaced boxes have been considered, and a wave-wave interaction phenomenon was observed in the case of closely spaced obstacles. Moreover reflection coefficients have been established and some pressure variations over the surfaces have been observed. An acoustic appriximation has been used to model the blast wave originating from an expanding sphere. It has been demonstrated, that the generated pressure pulse is very sensitive to the expansion rate. Calculated and measured data have been compared, and a reasonable agreement has been found. (author)

  7. Liquid explosives

    CERN Document Server

    Liu, Jiping

    2015-01-01

    The book drawing on the author's nearly half a century of energetic materials research experience intends to systematically review the global researches on liquid explosives. The book focuses on the study of the conception, explosion mechanism, properties and preparation of liquid explosives. It provides a combination of theoretical knowledge and practical examples in a reader-friendly style. The book is likely to be interest of university researchers and graduate students in the fields of energetic materials, blasting engineering and mining.

  8. Investigation of the Behavioral Characteristics of Dogs Purpose-Bred and Prepared to Perform Vapor Wake® Detection of Person-Borne Explosives

    Directory of Open Access Journals (Sweden)

    Lucia Lazarowski

    2018-03-01

    Full Text Available Specialized detector dogs are increasingly being utilized for the detection of modern threats. The Vapor Wake® (VW dog was developed to create a dog phenotype ideally suited for detecting hand-carried and body-worn explosives. VW dogs (VWDs are trained to sample and alert to target odors in the aerodynamic wakes of moving persons, which entrains vapor and small particles from the person. The behavioral characteristics necessary for dogs to be successfully trained and employed for the application of VW are a distinct subset of the desired general characteristics of dogs used for detection tasks due to the dynamic nature of moving targets. The purpose of this study was to examine the behavioral characteristics of candidate detector dogs to determine the particular qualities that set apart VW-capable dogs from others. We assessed 146 candidate detector dogs from a VW breeding and training program. Dogs received identical puppy development and foundational odor training and underwent performance evaluations at 3, 6, 10, and 12 months old, after which they were sold for service. Dogs were categorized based on their final outcome of the training program, independently determined by private vendors, corresponding to three groups: dogs successfully sold for VW, dogs sold for standard explosives detection, and dogs that failed to be placed in any type of detector dog service (Washouts. Comparisons of behavioral evaluations between the groups were made across domains pertaining to search-related behaviors (Performance, reactions to novel stimuli (Environmental, and overall ease of learning new tasks (Trainability. Comparisons were also made at each evaluation to determine any early emergence of differences. VWDs scored significantly higher on Performance characteristics compared to standard explosives detection dogs (EDDs and Washouts. However, Environmental characteristics did not differentiate VWDs from EDDs, though scores on these measures were

  9. Investigation of the Behavioral Characteristics of Dogs Purpose-Bred and Prepared to Perform Vapor Wake® Detection of Person-Borne Explosives.

    Science.gov (United States)

    Lazarowski, Lucia; Haney, Pamela Sue; Brock, Jeanne; Fischer, Terry; Rogers, Bart; Angle, Craig; Katz, Jeffrey S; Waggoner, L Paul

    2018-01-01

    Specialized detector dogs are increasingly being utilized for the detection of modern threats. The Vapor Wake ® (VW) dog was developed to create a dog phenotype ideally suited for detecting hand-carried and body-worn explosives. VW dogs (VWDs) are trained to sample and alert to target odors in the aerodynamic wakes of moving persons, which entrains vapor and small particles from the person. The behavioral characteristics necessary for dogs to be successfully trained and employed for the application of VW are a distinct subset of the desired general characteristics of dogs used for detection tasks due to the dynamic nature of moving targets. The purpose of this study was to examine the behavioral characteristics of candidate detector dogs to determine the particular qualities that set apart VW-capable dogs from others. We assessed 146 candidate detector dogs from a VW breeding and training program. Dogs received identical puppy development and foundational odor training and underwent performance evaluations at 3, 6, 10, and 12 months old, after which they were sold for service. Dogs were categorized based on their final outcome of the training program, independently determined by private vendors, corresponding to three groups: dogs successfully sold for VW, dogs sold for standard explosives detection, and dogs that failed to be placed in any type of detector dog service (Washouts). Comparisons of behavioral evaluations between the groups were made across domains pertaining to search-related behaviors (Performance), reactions to novel stimuli (Environmental), and overall ease of learning new tasks (Trainability). Comparisons were also made at each evaluation to determine any early emergence of differences. VWDs scored significantly higher on Performance characteristics compared to standard explosives detection dogs (EDDs) and Washouts. However, Environmental characteristics did not differentiate VWDs from EDDs, though scores on these measures were significantly

  10. Scanning the melting curve of tungsten by a submicrosecond wire-explosion experiment

    International Nuclear Information System (INIS)

    Kloss, A.; Hess, H.; Schneidenbach, H.; Grossjohann, R.

    1999-01-01

    Measurements of temperature and density during a wire-explosion experiment at atmospheric pressure are described. The measurements encompass a parameter range from the solid to near the critical point. The influence of a polytetra-fluoroethylene coating of the wire, necessary to prevent surface discharges, on the temperature and density measurements is investigated. The melting curve of tungsten up to 4,000 K is determined

  11. A study on damage effect from boiling liquid expanding vapor explosion(Believe) of LPG charging facility

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Sam Kew; Ham, Eun Gu [Dept. of Architectural Engineering, Kwangwoon University (Korea); Kim, Tae Hwan [Automation System Research Institute, Seoul (Korea)

    1999-12-01

    The LPG refueling station's explosion at Bucheon city was a major accident which with rare frequency of occurrence and large damage effect. Therefore, to prevent similar accident in the future from LPG charging stations which located in urban area. It needs to identify the damage effects of such facilities by comparing theoretically quantities risk and actual damage. The BLEVE effects from the accident showed similar damage effect in case of heat flux, however, the overpressure level reflected at the reduced distance by 15%. The structure damage to the near by area showed comparatively large heat radiation damage to the concrete structure strength and shape changes through heat flux while the overpressure effect was small. 13 refs., 4 figs., 4 tabs.

  12. NASA Experiment on Tropospheric-Stratospheric Water Vapor Transport in the Intertropical Convergence Zone

    Science.gov (United States)

    Page, William A.

    1982-01-01

    The following six papers report preliminary results obtained from a field experiment designed to study the role of tropical cumulo-nimbus clouds in the transfer of water vapor from the troposphere to the stratosphere over the region of Panama. The measurements were made utilizing special NOAA enhanced IR satellite images, radiosonde-ozonesondes and a NASA U-2 aircraft carrying. nine experiments. The experiments were provided by a group of NASA, NOAA, industry, and university scientists. Measurements included atmospheric humidity, air and cloud top temperatures, atmospheric tracer constituents, cloud particle characteristics and cloud morphology. The aircraft made a total of eleven flights from August 30 through September 18, 1980, from Howard Air Force Base, Panama; the pilots obtained horizontal and vertical profiles in and near convectively active regions and flew around and over cumulo-nimbus towers and through the extended anvils in the stratosphere. Cumulo-nimbus clouds in the tropics appear to play an important role in upward water vapor transport and may represent the principal source influencing the stratospheric water vapor budget. The clouds provide strong vertical circulation in the troposphere, mixing surface air and its trace materials (water vapor, CFM's sulfur compounds, etc.) quickly up to the tropopause. It is usually assumed that large scale mean motions or eddy scale motions transport the trace materials through the tropopause and into the stratosphere where they are further dispersed and react with other stratospheric constituents. The important step between the troposphere and stratosphere for water vapor appears to depend upon the processes occurring at or near the tropopause at the tops of the cumulo-nimbus towers. Several processes have been sugested: (1) The highest towers penetrate the tropopause and carry water in the form of small ice particles directly into the stratosphere. (2) Water vapor from the tops of the cumulonimbus clouds is

  13. Reactive flow modeling of small scale detonation failure experiments for a baseline non-ideal explosive

    Energy Technology Data Exchange (ETDEWEB)

    Kittell, David E.; Cummock, Nick R.; Son, Steven F. [School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

    2016-08-14

    Small scale characterization experiments using only 1–5 g of a baseline ammonium nitrate plus fuel oil (ANFO) explosive are discussed and simulated using an ignition and growth reactive flow model. There exists a strong need for the small scale characterization of non-ideal explosives in order to adequately survey the wide parameter space in sample composition, density, and microstructure of these materials. However, it is largely unknown in the scientific community whether any useful or meaningful result may be obtained from detonation failure, and whether a minimum sample size or level of confinement exists for the experiments. In this work, it is shown that the parameters of an ignition and growth rate law may be calibrated using the small scale data, which is obtained from a 35 GHz microwave interferometer. Calibration is feasible when the samples are heavily confined and overdriven; this conclusion is supported with detailed simulation output, including pressure and reaction contours inside the ANFO samples. The resulting shock wave velocity is most likely a combined chemical-mechanical response, and simulations of these experiments require an accurate unreacted equation of state (EOS) in addition to the calibrated reaction rate. Other experiments are proposed to gain further insight into the detonation failure data, as well as to help discriminate between the role of the EOS and reaction rate in predicting the measured outcome.

  14. CVB: The Constrained Vapor Bubble 40 mm Capillary Experiment on the ISS

    Science.gov (United States)

    Wayner, Peter C., Jr.; Kundan, Akshay; Plawsky, Joel

    2013-01-01

    Discuss the Constrained Vapor Bubble (CVB) 40mm Fin experiment on the ISS and how it aims to achieve a better understanding of the physics of evaporation and condensation and how they affect cooling processes in microgravity using a remotely controlled microscope and a small cooling device

  15. Explosions and static electricity

    DEFF Research Database (Denmark)

    Jonassen, Niels M

    1995-01-01

    The paper deals with the problem of electrostatic discharges as causes of ignition of vapor/gas and dust/gas mixtures. A series of examples of static-caused explosions will be discussed. The concepts of explosion limits, the incendiveness of various discharge types and safe voltages are explained...

  16. Laser pulse propagation in a meter scale rubidium vapor/plasma cell in AWAKE experiment

    CERN Document Server

    Joulaei, Atefeh; Berti, Nicolas; Kasparian, Jerome; Mirzanejhad, Saeed; Muggli, Patric

    2016-01-01

    We present the results of numerical studies of laser pulse propagating in a 3.5 cm Rb vapor cell in the linear dispersion regime by using a 1D model and a 2D code that has been modified for our special case. The 2D simulation finally aimed at finding laser beam parameters suitable to make the Rb vapor fully ionized to obtain a uniform, 10 m-long, at least 1 mm in radius plasma in the next step for the AWAKE experiment.

  17. Laser pulse propagation in a meter scale rubidium vapor/plasma cell in AWAKE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Joulaei, A. [Max-Planck Institute for Physics, Munich (Germany); University of Mazandaran (Iran, Islamic Republic of); Moody, J. [Max-Planck Institute for Physics, Munich (Germany); Berti, N.; Kasparian, J. [University of Geneva (Switzerland); Mirzanejhad, S. [University of Mazandaran (Iran, Islamic Republic of); Muggli, P. [Max-Planck Institute for Physics, Munich (Germany)

    2016-09-01

    We present the results of numerical studies of laser pulse propagating in a 3.5 cm Rb vapor cell in the linear dispersion regime by using a 1D model and a 2D code that has been modified for our special case. The 2D simulation finally aimed at finding laser beam parameters suitable to make the Rb vapor fully ionized to obtain a uniform, 10 m-long, at least 1 mm in radius plasma in the next step for the AWAKE experiment. - Highlights: • Discussion the AWAKE plasma source based on photoionization of rubidium vapor with a TW/cm^2 Intensity laser with a spectrum across valence ground state transition resonances. • Examines the propagation of the AWAKE ionization laser through rubidium vapor at design density on a small scale and reduced intensity with a linear numerical model compared to experimental results. • Discusses physics of pulse propagation through the vapor at high intensity regime where strong ionization occurs within the laser pulse.

  18. Effect of the steam explosion pretreatment on enzymatic hydrolysis of eucalyptus wood and sweet sorghum baggages; Efecto del pretratamiento con explosion por vapor en la hidrolisis enzimatica de madera de eucalipto y bagazo de sorgo

    Energy Technology Data Exchange (ETDEWEB)

    Negro, M J; Martinez, J M; Manero, J; Saez, F; Martin, C

    1991-07-01

    The effect of steam explosion treatment on the enzymatic hydrolysis yield of two different lignocellulosic substrates is studied. Raw materials have been pretreated in a pilot plant designed to work in batch and equipped with a reactor vessel of 2 1 working volume where biomass was heated at the desired temperature and then exploded and recovered in a cyclone. Temperatures from 190 to 230 degree celsius and reaction times from 2 to 8 min. have been assayed. The efficiency of the steam explosion treatment has been evaluated on the composition of the lignocellulosic materials as well as on their enzymatic hydrolysis yield using a cellulolytic complex from T. reesel. Results show a high solubilization rate of hemicelluloses and variable losses of cellulose and lignin depending on the conditions tested. Enzymatic hydrolysis yields of both substrates experimented remarkable increments, corresponding the highest values obtained to 210 degree celsius; 2 min. and 21O degree celsius; 4 min. for sorghum bagasse and eucalyptus wood respectively. (Author) 13 refs.

  19. Experiment HFR-B1: A preliminary analysis of the water-vapor injection experiments in capsule 3

    International Nuclear Information System (INIS)

    Myers, B.F.

    1993-01-01

    A preliminary analysis of the response of uranium oxycarbide (UCO) fuel to water vapor addition in capsule 3 of experiment HFR-B1 (HFR-B1/3) has been conducted. The analysis provides an early indication of the behavior of fission gas release under a wider range of water-vapor pressures and of temperatures than heretofore studied. A preliminary analysis of selected aspects of the water-vapor injection tests in capsule 3 of experiment HFR-B1 is presented. The release of fission gas stored in bubbles and the diffusive release of fission-gas atoms are distinguished. The dependence of the release of stored fission gas ( 85m Kr) on water-vapor pressure, P(H 2 O), and temperature were established taking into account the contributing mechanisms of gaseous release, the effect of graphite hydrolysis, and the requirement of consistency with experiment HRB-17 in which similar water-vapor injection tests were conducted. The dependence on P(H 2 O) becomes weaker as temperatures increase above 770 degree C; the activation energy for release of stored-fission gas is 393 kJ/mol. Isorelease curves for the pressure-temperature plane were deduced from a derived functional relation. The stored-fission gas releases as a function of P(H 2 O) at a common temperature for experiments HFR-B1 and HRB-17 differ by a factor of 4; this discrepancy could be attributed to the differences in fission-rate density and neutron flux between the two experiments. Diffusive release of fission gas occurred during and after the release of stored gas. The ratio of diffusive release during water-vapor injection to that prior to injection varied in contrast to the results from HRB-17. The variation was attributed to the practice of injecting water vapor into HFR-B1 before sintering of the fuel, hydrolyzed in the previous test, was completed. The derived activation energy for diffusive release is 23.6 kJ/mol

  20. Experiment HFR-B1: A preliminary analysis of the water-vapor injection experiments in capsule 3

    Energy Technology Data Exchange (ETDEWEB)

    Myers, B.F.

    1993-08-01

    A preliminary analysis of the response of uranium oxycarbide (UCO) fuel to water vapor addition in capsule 3 of experiment HFR-B1 (HFR-B1/3) has been conducted. The analysis provides an early indication of the behavior of fission gas release under a wider range of water-vapor pressures and of temperatures than heretofore studied. A preliminary analysis of selected aspects of the water-vapor injection tests in capsule 3 of experiment HFR-B1 is presented. The release of fission gas stored in bubbles and the diffusive release of fission-gas atoms are distinguished. The dependence of the release of stored fission gas ({sup 85m}Kr) on water-vapor pressure, P(H{sub 2}O), and temperature were established taking into account the contributing mechanisms of gaseous release, the effect of graphite hydrolysis, and the requirement of consistency with experiment HRB-17 in which similar water-vapor injection tests were conducted. The dependence on P(H{sub 2}O) becomes weaker as temperatures increase above 770{degree}C; the activation energy for release of stored-fission gas is 393 kJ/mol. Isorelease curves for the pressure-temperature plane were deduced from a derived functional relation. The stored-fission gas releases as a function of P(H{sub 2}O) at a common temperature for experiments HFR-B1 and HRB-17 differ by a factor of 4; this discrepancy could be attributed to the differences in fission-rate density and neutron flux between the two experiments. Diffusive release of fission gas occurred during and after the release of stored gas. The ratio of diffusive release during water-vapor injection to that prior to injection varied in contrast to the results from HRB-17. The variation was attributed to the practice of injecting water vapor into HFR-B1 before sintering of the fuel, hydrolyzed in the previous test, was completed. The derived activation energy for diffusive release is 23.6 kJ/mol.

  1. Explosive Leidenfrost droplets

    Science.gov (United States)

    Colinet, Pierre; Moreau, Florian; Dorbolo, Stéphane

    2017-11-01

    We show that Leidenfrost droplets made of an aqueous solution of surfactant undergo a violent explosion in a wide range of initial volumes and concentrations. This unexpected behavior turns out to be triggered by the formation of a gel-like shell, followed by a sharp temperature increase. Comparing a simple model of the radial surfactant distribution inside a spherical droplet with experiments allows highlighting the existence of a critical surface concentration for the shell to form. The temperature rise (attributed to boiling point elevation with surface concentration) is a key feature leading to the explosion, instead of the implosion (buckling) scenario reported by other authors. Indeed, under some conditions, this temperature increase is shown to be sufficient to trigger nucleation and growth of vapor bubbles in the highly superheated liquid bulk, stretching the surrounding elastic shell up to its rupture limit. The successive timescales characterizing this explosion sequence are also discussed. Funding sources: F.R.S. - FNRS (ODILE and DITRASOL projects, RD and SRA positions of P. Colinet and S. Dorbolo), BELSPO (IAP 7/38 MicroMAST project).

  2. ECO steam explosion experiments on the conversion of thermal into mechanical energy

    International Nuclear Information System (INIS)

    Cherdron, W.; Kaiser, A.; Schuetz, W.; Will, H.

    2001-01-01

    In case of a steam explosion, e.g. as a consequence of a severe reactor accident, part of the thermal energy of the melt is transferred into mechanical energy. At Forschungszentrum Karlsruhe, so-called ECO experiments, are being directed to measure the conversion factor under well-defined conditions. In ECO, alumina from a thermite reaction is used as a simulating material instead of corium. Dimensions of the test facility as well as major test conditions, e.g. temperature and release mode of the melt, water inventory and test procedure, are based on the former PREMIX experimental series. In the paper, results of the first test, ECO 01, are given. (orig.)

  3. Preliminary experiments using light-initiated high explosive for driving thin flyer plates

    International Nuclear Information System (INIS)

    Benham, R.A.

    1980-02-01

    Light-initiated high explosive, silver acelytide - silver-nitrate (SASN), has been used to produce simulated x ray blow-off impulse loading on reentry vehicles to study the system structural response. SASN can be used to accelerate thin flyer plates to high terminal velocities which, in turn, can deliver a pressure pulse that can be tailored to the target material. This process is important for impulse tests where both structural and material response is desired. The theories used to calculate the dynamic state of the flyer plate prior to impact are summarized. Data from several experiments are presented which indicate that thin flyer plates can be properly accelerated and that there are predictive techniques available which are adequate to calculate the motion of the flyer plate. Recommendations are made for future study that must be undertaken to make the SASN flyer plate technique usable

  4. Generation of pyroclastic density currents from pyroclastic fountaining or transient explosions: insights from large scale experiments

    Energy Technology Data Exchange (ETDEWEB)

    Sulpizio, Roberto; Dellino, Pierfrancesco; Mele, Daniela; La Volpe, Luigi [CIRISIVU, c/o Dipartimento Geomineralogico, via Orabona 4, 70125, Bari (Italy)], E-mail: r.sulpizio@geomin.uniba.it

    2008-10-01

    Pyroclastic density currents (PDCs) are among the most amazing, complex and dangerous volcanic phenomena. They are moving mixtures of particles and gas that flow across the ground, and originate in different ways and from various sources, during explosive eruptions or gravity-driven collapse of domes. We present results from experimental work to investigate the generation of large-scale, multiphase, gravity-driven currents. The experiments described here are particularly devoted to understanding the inception and development of PDCs under impulsive injection conditions by means of the fast application of a finite stress to a finite mass of pyroclastic particles via expansion of compressed gas. We find that, in summary, PDC generation from collapse of pressure-adjusted or overpressurised pyroclastic jets critically depends on behaviour of injection into the atmosphere, which controls the collapsing mechanisms and then the physical parameters of the initiating current.

  5. Radiographic x-ray flux monitoring during explosive experiments by copper activation

    International Nuclear Information System (INIS)

    Goosman, D.R.

    1986-01-01

    During radiographic experiments involving explosives, it is valuable to have a method of monitoring the X-ray flux ratio between the dynamic experiment and an X-ray taken of a static object for comparison. The standard method of monitoring with thermoluminescent detectors suffers the disadvantages of being sensitive to temperature, shock, UV radiation, cleanliness and saturation. We are studying an additional flux monitoring system which is not subject to any of the above disadvantages and is based upon the 63 Cu(photon,n) 62 Cu reaction. The 62 Cu has a 10 min. half-life and is counted by a nuclear pulse-counting system within a few minutes of an explosive test. 170 MicroCoulomb of 19.3 MeV electrons hitting 1.18mm of Ta produces X-rays which illuminate a 0.8mm thick by 1.6cm diameter Cu disk placed 46cm from the Ta. The activated Cu is placed in a counting system with a window between 400-600 keV and produces about 42500 counts in the first 100 sec counting period. Less than 0.2% of the initial activity is due to other reactions. Photo-induced neutrons in Be parts of the system are shown to produce a negligible effect in the Cu. The main disadvantage of the Cu activation is its sensitivity to electron energy. Monte-Carlo calculations of the excitation function for our accelerator are shown, along with excitation functions for three other configurations

  6. Radiographic x-ray flux monitoring during explosive experiments by copper activation

    International Nuclear Information System (INIS)

    Goosman, D.R.

    1986-01-01

    During radiographic experiments involving explosives, it is valuable to have a method of monitoring the x-ray flux ratio between the dynamic experiment and an x-ray taken of a static object for comparison. The standard method of monitoring with thermoluminescent detectors suffers the disadvantages of being sensitive to temperature, shock, uv radiation, cleanliness and saturation. A flux monitoring system is being studied which is not subject to any of the above disadvantages and is based upon the 63Cu(photon,n)62Cu reaction. The 62Cu has a 10 min half life and is counted by a nuclear pulse counting system within a few minutes of an explosive test. 170 microcoulomb of 19.3 MeV electrons hitting 1.18 mm of Ta produces x-rays which illuminate a 0.8mm thick by 1.6 cm diameter Cu disk placed 46 cm from the Ta. The activated Cu is placed in a counting system with a window between 400 to 600 keV and produces about 42,500 counts in the first 100 sec. counting period. Less than 0.2% of the initial activity is due to other reactions. Photo-induced neutrons in Be parts of the system are shown to produce a negligible effect in the Cu. The main disadvantage of the Cu activation is its sensitivity to electron energy. Monte-Carlo calculations of the excitation function for our accelerator are shown, along with excitation functions for three other configurations

  7. GPS Water Vapor Tomography: First results from the ESCOMPTE Field Experiment

    Science.gov (United States)

    Masson, F.; Champollion, C.; Bouin, M.-N.; Walpersdorf, A.; van Baelen, J.; Doerflinger, E.; Bock, O.

    2003-04-01

    We develop a tomographic software to model the spatial distribution of the tropospheric water vapor from GPS data. First we present simulations based on a real GPS station distribution and simple tropospheric models, which prove the potentiality of the method. Second we apply the software to the ESCOMPTE data. During the ESCOMPTE field experiment, a dense network of 17 dual frequency GPS receivers has been operated for two weeks within a 20 km x 20 km area around Marseille (Southern France). The network extends from the sea level to the top of the Etoile chain (~700 m high). The input data are the slant delay values obtained by combining the estimated zenith delay values with the horizontal gradients. The effect of the initial tropospheric water vapor model, the number and thickness of the layers of the model, the a priori model and data covariance and some other parameters will be discussed. Simultaneously water vapor radiometer, solar spectrometer, Raman lidar and radiosondes have been deployed to get a data set usable for comparison with the tomographic inversion results and validation of the method. Comparison with meteorological models (MesoNH - Meteo-France) will be shown.

  8. The use of contained nuclear explosions to create underground reservoirs, and experience of operating these for gas condensate storage

    International Nuclear Information System (INIS)

    Kedrovskij, O.L.; Myasnikov, K.V.; Leonov, E.A.; Romadin, N.M.; Dorodnov, V.F.; Nikiforov, G.A.

    1975-01-01

    Investigations on the creation of underground reservoirs by means of nuclear explosions have been going on in the Soviet Union for many years. In this paper the authors consider three main kinds of sites or formations that can be used for constructing reservoirs by this method, namely, low-permeable rocks, worked-out mines and rock salt formations. Formulae are given for predicting the mechanical effect of an explosion in rocks, taking their strength characteristics into account. Engineering procedures are described for sealing and restoring the emplacement holes, so that they can be used for operating the underground reservoir. Experience with the contruction and operation of a 50 000 m 3 gas-condensate reservoir in a rock salt formation is described. In the appendix to the paper a method is presented for calculating the stability of spherical cavities created by nuclear explosions in rock salt, allowing for the development of elasto-plastic deformations and creep

  9. Steam explosion studies review

    International Nuclear Information System (INIS)

    Hwang, Moon Kyu; Kim, Hee Dong

    1999-03-01

    When a cold liquid is brought into contact with a molten material with a temperature significantly higher than the liquid boiling point, an explosive interaction due to sudden fragmentation of the melt and rapid evaporation of the liquid may take place. This phenomenon is referred to as a steam explosion or vapor explosion. Depending upon the amount of the melt and the liquid involved, the mechanical energy released during a vapor explosion can be large enough to cause serious destruction. In hypothetical severe accidents which involve fuel melt down, subsequent interactions between the molten fuel and coolant may cause steam explosion. This process has been studied by many investigators in an effort to assess the likelihood of containment failure which leads to large scale release of radioactive materials to the environment. In an effort to understand the phenomenology of steam explosion, extensive studies has been performed so far. The report presents both experimental and analytical studies on steam explosion. As for the experimental studies, both small scale tests which involve usually less than 20 g of high temperature melt and medium/large scale tests which more than 1 kg of melt is used are reviewed. For the modelling part of steam explosions, mechanistic modelling as well as thermodynamic modelling is reviewed. (author)

  10. On the fallout by nuclear explosion experiment and the radioactive iodine in animal organism

    International Nuclear Information System (INIS)

    Tanaka, Giichiro

    1974-01-01

    Radioactive iodine (mainly 131 I, 132 I, 133 I, and 135 I) was measured with fallout, cow milk, human urine, and thyroid glands (human and cattles) after the first nuclear explosion experiment in China. Analysing method was determined by placing emphasis on rapidity and perfect separation from other nuclides. The detectable limit employing this method was about several p Ci. The identification of radioactive iodine was performed with a simultaneous counting type β - ray spectrometer, and 131 I, 132 I, and 133 I were identified by their half lives. 131 I in cow milk increased from around the 4th day after the experiment, and it had been detected for a month continuously, the maximum amount being 437 p Ci/l. In thyroid glands, 131 I was detected for 100 days in a milch cow, the maximum being 88, 1p Ci/g, while it was somewhat low in Japanese cows and pigs. 131 I in the thyroid gland of a human infant (accidentally died after 12 days) was 1.29p Ci/g. 131 I in human urine was 6.3p Ci/l on the 7th day. (Kobatake, H.)

  11. Korea-France collaboration for the preparation of joint proposal for the OECD project on the steam explosion experiments

    International Nuclear Information System (INIS)

    Song, Jin Ho; Kim, H. D.; Kim, J. H.; Hong, S. W.; Min, B. T.; Park, I. K.

    2004-07-01

    There are some difficulties in design of the new reactor containment and in establishment of accident management strategy for operating reactors, since there exist a few phenomenological uncertainties in a steam explosion which occurs at the time of the interaction between the corium melt and coolant. So, the OECD/NEA recommended a research which could finalize the unsolved issues in a steam explosion and then an international collaborative research involving US, France, Germany, Japan and Korea, so called the SERENA (Steam Explosion Resolution for Nuclear Application) started in 2002. The first phase of this collaborative research is an analytical research and the second phase is planned to be an experimental research which will start in 2005. Korea and France agreed that both countries would cooperate in the second phase of the SERENA program at the specialist meetings and collaborative committee between the KAERI (Korea Atomic Energy Research Institute) and the CEA (Commissariat a l'Energie Atomique). This preparation research is performed in order to carry out the agreement between Korea and France and propose a collaborative research to the SERENA second phase. The contents of this research is to perform a collaborative research between Korea and France to propose an international collaborative research on a steam explosion research to the OECD. The scope includes the technical exchange for the construction of an international collaborative research and the preparation of a proposal for an international collaborative research for the OECD steam explosion program. Two steam explosion specialist meetings were held to discuss the technical issues in the TROI and KROTOS experiments. A formal accession and amendment agreement for the collaboration was contracted between the KAERI/KINS/CEA/IRSN. And the KAERI's capability to perform an international collaborative research was proved by advertizing the TROI test results to the USNRC/CSARP and JAERI. Also, the English

  12. Trace explosives sensor testbed (TESTbed)

    Science.gov (United States)

    Collins, Greg E.; Malito, Michael P.; Tamanaha, Cy R.; Hammond, Mark H.; Giordano, Braden C.; Lubrano, Adam L.; Field, Christopher R.; Rogers, Duane A.; Jeffries, Russell A.; Colton, Richard J.; Rose-Pehrsson, Susan L.

    2017-03-01

    A novel vapor delivery testbed, referred to as the Trace Explosives Sensor Testbed, or TESTbed, is demonstrated that is amenable to both high- and low-volatility explosives vapors including nitromethane, nitroglycerine, ethylene glycol dinitrate, triacetone triperoxide, 2,4,6-trinitrotoluene, pentaerythritol tetranitrate, and hexahydro-1,3,5-trinitro-1,3,5-triazine. The TESTbed incorporates a six-port dual-line manifold system allowing for rapid actuation between a dedicated clean air source and a trace explosives vapor source. Explosives and explosives-related vapors can be sourced through a number of means including gas cylinders, permeation tube ovens, dynamic headspace chambers, and a Pneumatically Modulated Liquid Delivery System coupled to a perfluoroalkoxy total-consumption microflow nebulizer. Key features of the TESTbed include continuous and pulseless control of trace vapor concentrations with wide dynamic range of concentration generation, six sampling ports with reproducible vapor profile outputs, limited low-volatility explosives adsorption to the manifold surface, temperature and humidity control of the vapor stream, and a graphical user interface for system operation and testing protocol implementation.

  13. LASE measurements of water vapor and aerosol profiles during the Plains Elevated Convection at Night (PECAN) field experiment

    Science.gov (United States)

    Nehrir, A. R.; Ferrare, R. A.; Kooi, S. A.; Butler, C. F.; Notari, A.; Hair, J. W.; Collins, J. E., Jr.; Ismail, S.

    2015-12-01

    The Lidar Atmospheric Sensing Experiment (LASE) system was deployed on the NASA DC-8 aircraft during the Plains Elevated Convection At Night (PECAN) field experiment, which was conducted during June-July 2015 over the central and southern plains. LASE is an active remote sensor that employs the differential absorption lidar (DIAL) technique to measure range resolved profiles of water vapor and aerosols above and below the aircraft. The DC-8 conducted nine local science flights from June 30- July 14 where LASE sampled water vapor and aerosol fields in support of the PECAN primary science objectives relating to better understanding nocturnal Mesoscale Convective Systems (MCSs), Convective Initiation (CI), the Low Level Jet (LLJ), bores, and to compare different airborne and ground based measurements. LASE observed large spatial and temporal variability in water vapor and aerosol distributions in advance of nocturnal MCSs, across bores resulting from MCS outflow boundaries, and across the LLJ associated with the development of MCSs and CI. An overview of the LASE data collected during the PECAN field experiment will be presented where emphasis will be placed on variability of water vapor profiles in the vicinity of severe storms and intense convection in the central and southern plains. Preliminary comparisons show good agreement between coincident LASE and radiosonde water vapor profiles. In addition, an advanced water vapor DIAL system being developed at NASA Langley will be discussed.

  14. Explosion Generated Seismic Waves and P/S Methods of Discrimination from Earthquakes with Insights from the Nevada Source Physics Experiments

    Science.gov (United States)

    Walter, W. R.; Ford, S. R.; Pitarka, A.; Pyle, M. L.; Pasyanos, M.; Mellors, R. J.; Dodge, D. A.

    2017-12-01

    The relative amplitudes of seismic P-waves to S-waves are effective at identifying underground explosions among a background of natural earthquakes. These P/S methods appear to work best at frequencies above 2 Hz and at regional distances ( >200 km). We illustrate this with a variety of historic nuclear explosion data as well as with the recent DPRK nuclear tests. However, the physical basis for the generation of explosion S-waves, and therefore the predictability of this P/S technique as a function of path, frequency and event properties such as size, depth, and geology, remains incompletely understood. A goal of current research, such as the Source Physics Experiments (SPE), is to improve our physical understanding of the mechanisms of explosion S-wave generation and advance our ability to numerically model and predict them. The SPE conducted six chemical explosions between 2011 and 2016 in the same borehole in granite in southern Nevada. The explosions were at a variety of depths and sizes, ranging from 0.1 to 5 tons TNT equivalent yield. The largest were observed at near regional distances, with P/S ratios comparable to much larger historic nuclear tests. If we control for material property effects, the explosions have very similar P/S ratios independent of yield or magnitude. These results are consistent with explosion S-waves coming mainly from conversion of P- and surface waves, and are inconsistent with source-size based models. A dense sensor deployment for the largest SPE explosion allowed this conversion to be mapped in detail. This is good news for P/S explosion identification, which can work well for very small explosions and may be ultimately limited by S-wave detection thresholds. The SPE also showed explosion P-wave source models need to be updated for small and/or deeply buried cases. We are developing new P- and S-wave explosion models that better match all the empirical data. Historic nuclear explosion seismic data shows that the media in which

  15. Investigating the dynamics of Vulcanian explosions: scaled laboratory experiments of particle-laden puffs

    Science.gov (United States)

    Clarke, A. B.; Phillips, J. C.; Chojnicki, K. N.

    2006-12-01

    Scaled laboratory experiments analogous to Vulcanian eruptions were conducted, producing particle-laden jets and plumes. A reservoir of a mixture of water and isopropanol plus solid particles (kaolin or Ballotini glass spheres) was pressurized and suddenly released via a rapid-release valve into a 2 ft by 2 ft by 4 ft plexiglass tank containing fresh water. The duration of the subsequent flow was limited by the potential energy associated with the pressurized fluid rather than by the available volume of fluid or by the duration of the valve opening. Particle size (4 &45 microns) and concentration (0 to 10 vol%) were varied in order to change particle settling characteristics and control bulk mixture density (960 kg m-3 to 1060 kg m-3). Water and isopropanol in varying proportions created a light interstitial fluid to simulate buoyant volcanic gases in erupted mixtures. Variations in reservoir pressure and vent size allowed exploration of controlling source parameters; total momentum injected (M) and total buoyancy injected (B). Mass flux at the vent was measured by an in-line Coriolis flowmeter sampling at 100 Hz, allowing rapidly varying M and B to be recorded. The velocity-height relationship of each experiment was measured from high-speed video footage, permitting classification into the following groups: long continuously accelerating jets; accelerating jets transitioning to plumes; and collapsing fountains which generated density currents. Field-documented Vulcanian explosions exhibit this same wide range of behavior, demonstrating that regimes obtained in the laboratory are relevant to natural systems. A generalized framework of results was defined as follows. Increasing M/B for small particles (4 microns; settling time>>experiment duration) pushes the system from collapsing fountains to low-energy plumes to high-energy, continuously accelerating jets; increasing M/B for large particles (45 microns; settling time non-dimensional groups were combined to

  16. CVB: the Constrained Vapor Bubble Capillary Experiment on the International Space Station MARANGONI FLOW REGION

    Science.gov (United States)

    Wayner, Peter C., Jr.; Kundan, Akshay; Plawsky, Joel

    2014-01-01

    The Constrained Vapor Bubble (CVB) is a wickless, grooved heat pipe and we report on a full- scale fluids experiment flown on the International Space Station (ISS). The CVB system consists of a relatively simple setup a quartz cuvette with sharp corners partially filled with either pentane or an ideal mixture of pentane and isohexane as the working fluids. Along with temperature and pressure measurements, the two-dimensional thickness profile of the menisci formed at the corners of the quartz cuvette was determined using the Light Microscopy Module (LMM). Even with the large, millimeter dimensions of the CVB, interfacial forces dominate in these exceedingly small Bond Number systems. The experiments were carried out at various power inputs. Although conceptually simple, the transport processes were found to be very complex with many different regions. At the heated end of the CVB, due to a high temperature gradient, we observed Marangoni flow at some power inputs. This region from the heated end to the central drop region is defined as a Marangoni dominated region. We present a simple analysis based on interfacial phenomena using only measurements from the ISS experiments that lead to a predictive equation for the thickness of the film near the heated end of the CVB. The average pressure gradient for flow in the film is assumed due to the measured capillary pressure at the two ends of the liquid film and that the pressure stress gradient due to cohesion self adjusts to a constant value over a distance L. The boundary conditions are the no slip condition at the wall interface and an interfacial shear stress at the liquid- vapor interface due to the Marangoni stress, which is due to the high temperature gradient. Although the heated end is extremely complex, since it includes three- dimensional variations in radiation, conduction, evaporation, condensation, fluid flow and interfacial forces, we find that using the above simplifying assumptions, a simple successful

  17. Active sampling technique to enhance chemical signature of buried explosives

    Science.gov (United States)

    Lovell, John S.; French, Patrick D.

    2004-09-01

    Deminers and dismounted countermine engineers commonly use metal detectors, ground penetrating radar and probes to locate mines. Many modern landmines have a very low metal content, which severely limits the effectiveness of metal detectors. Canines have also been used for landmine detection for decades. Experiments have shown that canines smell the explosives which are known to leak from most types of landmines. The fact that dogs can detect landmines indicates that vapor sensing is a viable approach to landmine detection. Several groups are currently developing systems to detect landmines by "sniffing" for the ultra-trace explosive vapors above the soil. The amount of material that is available to passive vapor sensing systems is limited to no more than the vapor in equilibrium with the explosive related chemicals (ERCs) distributed in the surface soils over and near the landmine. The low equilibrium vapor pressure of TNT in the soil/atmosphere boundary layer and the limited volume of the boundary layer air imply that passive chemical vapor sensing systems require sensitivities in the picogram range, or lower. ADA is working to overcome many of the limitations of passive sampling methods, by the use of an active sampling method that employs a high-powered (1,200+ joules) strobe lamp to create a highly amplified plume of vapor and/or ERC-bearing fine particulates. Initial investigations have demonstrated that this approach can amplify the detectability of TNT by two or three orders of magnitude. This new active sampling technique could be used with any suitable explosive sensor.

  18. Shock-to-detonation transition of RDX and NTO based composite high explosives: experiments and modeling

    Science.gov (United States)

    Baudin, Gerard; Roudot, Marie; Genetier, Marc

    2013-06-01

    Composite HMX and NTO based high explosives (HE) are widely used in ammunitions. Designing modern warheads needs robust and reliable models to compute shock ignition and detonation propagation inside HE. Comparing to a pressed HE, a composite HE is not porous and the hot-spots are mainly located at the grain - binder interface leading to a different behavior during shock-to-detonation transition. An investigation of how shock-to-detonation transition occurs inside composite HE containing RDX and NTO is proposed in this lecture. Two composite HE have been studied. The first one is HMX - HTPB 82:18. The second one is HMX - NTO - HTPB 12:72:16. These HE have been submitted to plane sustained shock waves at different pressure levels using a laboratory powder gun. Pressure signals are measured using manganin gauges inserted at several distances inside HE. The corresponding run-distances to detonation are determined using wedge test experiments where the plate impact is performed using a powder gun. Both HE exhibit a single detonation buildup curve in the distance - time diagram of shock-to-detonation transition. This feature seems a common shock-to-detonation behavior for composite HE without porosity. This behavior is also confirmed for a RDX - HTPB 85:15 based composite HE. Such a behavior is exploited to determine the heterogeneous reaction rate versus the shock pressure using a method based on the Cauchy-Riemann problem inversion. The reaction rate laws obtained allow to compute both run-distance to detonation and pressure signals.

  19. Blast from explosive evaporation of carbon dioxide : Experiment, modeling and physics

    NARCIS (Netherlands)

    Van der Voort, M.M.; Van den berg, A.C.; Roekaerts, D.J.E.M.; Xie, M.; De Bruijn, P.C.J.

    2012-01-01

    Explosive evaporation of a superheated liquid is a relevant hazard in the process industry. A vessel rupture during storage, transport or handling may lead to devastating blast effects. In order to assess the risk associated with this hazard or to design protective measures, an accurate prediction

  20. Blast from explosive evaporation of carbon dioxide: Experiment, modeling and physics

    NARCIS (Netherlands)

    Voort, M.M. van der; Berg, A.C. van den; Roekaerts, D.J.E.M.; Xie, M.; Bruijn, P.C.J. de

    2012-01-01

    Explosive evaporation of a superheated liquid is a relevant hazard in the process industry. A vessel rupture during storage, transport or handling may lead to devastating blast effects. In order to assess the risk associated with this hazard or to design protective measures, an accurate prediction

  1. Study on the effect of subcooling on vapor film collapse on high temperature particle surface

    International Nuclear Information System (INIS)

    Abe, Yutaka; Tochio, Daisuke; Yanagida, Hiroshi

    2000-01-01

    Thermal detonation model is proposed to describe vapor explosion. According to this model, vapor film on pre-mixed high temperature droplet surface is needed to be collapsed for the trigger of the vapor explosion. It is pointed out that the vapor film collapse behavior is significantly affected by the subcooling of low temperature liquid. However, the effect of subcooling on micro-mechanism of vapor film collapse behavior is not experimentally well identified. The objective of the present research is to experimentally investigate the effect of subcooling on micro-mechanism of film boiling collapse behavior. As the results, it is experimentally clarified that the vapor film collapse behavior in low subcooling condition is qualitatively different from the vapor film collapse behavior in high subcooling condition. In case of vapor film collapse by pressure pulse, homogeneous vapor generation occurred all over the surface of steel particle in low subcooling condition. On the other hand, heterogeneous vapor generation was observed for higher subcooling condition. In case of vapor film collapse spontaneously, fluctuation of the gas-liquid interface after quenching propagated from bottom to top of the steel particle heterogeneously in low subcooling condition. On the other hand, simultaneous vapor generation occurred for higher subcooling condition. And the time transient of pressure, particle surface temperature, water temperature and visual information were simultaneously measured in the vapor film collapse experiment by external pressure pulse. Film thickness was estimated by visual data processing technique with the pictures taken by the high-speed video camera. Temperature and heat flux at the vapor-liquid interface were estimated by solving the heat condition equation with the measured pressure, liquid temperature and vapor film thickness as boundary conditions. Movement of the vapor-liquid interface were estimated with the PIV technique with the visual observation

  2. Time-Dependent Moment Tensors of the First Four Source Physics Experiments (SPE) Explosions

    Science.gov (United States)

    Yang, X.

    2015-12-01

    We use mainly vertical-component geophone data within 2 km from the epicenter to invert for time-dependent moment tensors of the first four SPE explosions: SPE-1, SPE-2, SPE-3 and SPE-4Prime. We employ a one-dimensional (1D) velocity model developed from P- and Rg-wave travel times for Green's function calculations. The attenuation structure of the model is developed from P- and Rg-wave amplitudes. We select data for the inversion based on the criterion that they show consistent travel times and amplitude behavior as those predicted by the 1D model. Due to limited azimuthal coverage of the sources and the mostly vertical-component-only nature of the dataset, only long-period, diagonal components of the moment tensors are well constrained. Nevertheless, the moment tensors, particularly their isotropic components, provide reasonable estimates of the long-period source amplitudes as well as estimates of corner frequencies, albeit with larger uncertainties. The estimated corner frequencies, however, are consistent with estimates from ratios of seismogram spectra from different explosions. These long-period source amplitudes and corner frequencies cannot be fit by classical P-wave explosion source models. The results motivate the development of new P-wave source models suitable for these chemical explosions. To that end, we fit inverted moment-tensor spectra by modifying the classical explosion model using regressions of estimated source parameters. Although the number of data points used in the regression is small, the approach suggests a way for the new-model development when more data are collected.

  3. The effect of explosive percentage on underwater explosion energy release of hexanitrohexaazaisowurtzitane and octogen based aluminized explosives

    OpenAIRE

    Qingjie Jiao; Qiushi Wang; Jianxin Nie; Xueyong Guo; Wei Zhang; Wenqi Fan

    2018-01-01

    To control the explosion energy output by optimizing explosive components is a key requirement in a number of different application areas. The effect of different Al/O Ratio on underwater explosion of aluminized explosives has been studied detailedly. However, the effect of explosive percentage in the same Al/O Ratio is rarely researched, especially for Hexanitrohexaazaisowurtzitane (CL-20) based aluminized explosives. In this study, we performed the underwater explosion experiments with 1.2-...

  4. Search for evidence of nuclear involvement in the fatal explosion of a 'cold fusion' experiment

    International Nuclear Information System (INIS)

    Grant, P.M.; Whipple, R.E.; Andresen, B.D.; Russo, R.E.; Bazan, F.; Brunk, J.L.; Wong, K.M.

    1995-01-01

    Forensic analyses of debris from the fatal explosion of an electrochemical 'cold fusion' cell at SRI International were conducted at LLNL at the request of Cal-OSHA. One investigation focused on the possibility of conventional nuclear reaction mechanisms contributing to the total energy inventory of the incident. Selected metal components of the electrolysis apparatus were subjected to nondestructive γ-ray spectrometry with high-sensitivity, low-background Ge detector systems. The anticipated analytes in these studies were radioactivation products potentially induced in the explosion residue by either fast or thermal neutrons. The results of this investigation were negative within the temporal constraints of the incident and the analytical sensitivities of the instrumentation. (author) 5 refs.; 1 fig.; 2 tabs

  5. Seismic decoupling of an explosion centered in a granite chimney rubble -- scaled experiment results. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Keller, C. [Science & Engineering Associates, Inc., Santa Fe, NM (United States); Miller, S.; Florence, A.; Fogle, M.; Kilb, D.

    1991-12-01

    This report describes the small scale evaluation of the feasibility of significant decoupling by siting an explosion in granite rubble. The chimney characteristics scaled to laboratory dimensions were those of the PILE DRIVER event. The scaled charges were of 1 KT and 8KT in the PILE DRIVER chimney. The measure of the effect was the velocity field history in the granite outside the chimney volume with the chimney rubble and with no rubble. A number of chimney sizes and shapes were studied. The explosion process was modeled via two-din=mensional, finite-difference methods used for prediction of velocity histories at the Nevada Test Site. The result was that both the spectral shape and the magnitude of the transmitted shock wave were drastically altered. The chimney geometry was as important as the rubble characteristics.

  6. Single-charge craters excavated during subsurface high-explosive experiments at Big Black Test Site, Mississippi

    International Nuclear Information System (INIS)

    Woodruff, W.R.; Bryan, J.B.

    1978-01-01

    Single-charge and row-charge subsurface cratering experiments were performed to learn how close-spacing enhances single-crater dimensions. Our first experimental phase established cratering curves for 60-lb charges of the chemical explosive. For the second phase, to be described in a subsequent report, the Row-cratering experiments were designed and executed. This data report contains excavated dimensions and auxiliary data for the single-charge cratering experiments. The dimensions for the row-charge experiments will be in the other report. Significant changes in the soil's water content appeared to cause a variability in the excavated dimensions. This variability clouded the interpretation and application of the cratering curves obtained

  7. Primary explosives

    Energy Technology Data Exchange (ETDEWEB)

    Matyas, Robert; Pachman, Jiri [Pardubice Univ. (Czech Republic). Faculty of Chemical Technology

    2013-06-01

    The first chapter provides background such as the basics of initiation and differences between requirements on primary explosives used in detonators and igniters. The authors then clarify the influence of physical characteristics on explosive properties, focusing on those properties required for primary explosives. Furthermore, the issue of sensitivity is discussed. All the chapters on particular groups of primary explosives are structured in the same way, including introduction, physical and chemical properties, explosive properties, preparation and documented use.

  8. Cause finding experiments and environmental analysis on the accident of the fire and explosion in TRP bituminization facility

    International Nuclear Information System (INIS)

    Fujine, Sachio; Murata, Mikio; Abe, Hitoshi

    1999-09-01

    This report is the summary of the cause finding experiments and environmental analysis on the accident of the fire and explosion occurred at March 11th, 1997, in TRP bituminization facility of PNC (Power Reactor and Nuclear Fuel Development Corporation). Regarding the cause finding experiments, chemical components have been analyzed for the effluent samples taken from PNC's facility, bituminized mock waste has been produced using the simulated salt effluent prepared according to the results of chemical analysis, thermal analysis and experiment of runaway exothermic reaction have been conducted using the mock waste, and the component of flammable gases emitted from the heated waste have been collected and analyzed. Regarding environmental analysis on the accident, the amount of radioactive cesium released by the accident has been calculated by the comparative analysis using the atmospheric dispersion simulation code SPEEDI with the data of environmental monitoring and the public dose has been assessed. (author)

  9. Review of literature on the asymmetric collapse of vapor bubbles

    International Nuclear Information System (INIS)

    Fremd, R.; Froehlich, G.

    1977-06-01

    This report contains a review of literature on the asymmetric collape of vapor bubbles by cavitation with special consideration to vapor explosions. Two numerical models, which describe the collapse of cavities in the neighbourhood of a solid surface, are presented. Moreover experimental results for this case are provided. Propositions to apply the numerical models to vapor explosions are made. (orig.) [de

  10. A summary of sodium vapor trap experience at the Fast Flux Test Facility

    International Nuclear Information System (INIS)

    Schuck, W.J.

    1986-09-01

    Sodium vapor trap operation at the Fast Flux Test Facility has been successful although not uneventful. Analysis and evaluation of the behavior of the vapor traps associated with reactor cover gas processing and analysis systems has confirmed their design and has led to an improved understanding of these components and the environment in which they operate. This knowledge will permit simplification and reduced costs for future designs

  11. A summary of sodium vapor trap experience at the Fast Flux Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Schuck, W J [Westinghouse Hanford Company, Richland, WA (United States)

    1987-07-01

    Sodium vapor trap operation at the Fast Flux Test Facility has been successful although not uneventful. Analysis and evaluation of the behavior of the vapor traps associated with reactor cover gas processing and analysis systems has confirmed their design and has led to an improved understanding of these components and the environment in which they operate. This knowledge will permit simplification and reduced costs for future designs (author)

  12. General phenomenology of underground nuclear explosions

    International Nuclear Information System (INIS)

    Derlich, S.; Supiot, F.

    1969-01-01

    An essentially qualitatively description is given of the phenomena related to underground nuclear explosions (explosion of a single unit, of several units in line, and simultaneous explosions). In the first chapter are described the phenomena which are common to contained explosions and to explosions forming craters (formation and propagation of a shock-wave causing the vaporization, the fusion and the fracturing of the medium). The second chapter describes the phenomena related to contained explosions (formation of a cavity with a chimney). The third chapter is devoted to the phenomenology of test explosions which form a crater; it describes in particular the mechanism of formation and the different types of craters as a function of the depth of the explosion and of the nature of the ground. The aerial phenomena connected with explosions which form a crater: shock wave in the air and focussing at a large distance, and dust clouds, are also dealt with. (authors) [fr

  13. GPS water vapor project associated to the ESCOMPTE programme: description and first results of the field experiment

    Science.gov (United States)

    Bock, O.; Doerflinger, E.; Masson, F.; Walpersdorf, A.; Van-Baelen, J.; Tarniewicz, J.; Troller, M.; Somieski, A.; Geiger, A.; Bürki, B.

    A dense network of 17 dual frequency GPS receivers has been operated for two weeks during June 2001 within a 20 km × 20 km area around Marseille, France, as part of the ESCOMPTE field campaign ([Cros et al., 2004. The ESCOMPTE program: an overview. Atmos. Res. 69, 241-279]; http://medias.obs-mip.fr/escompte). The goal of this GPS experiment was to provide GPS data allowing for tomographic inversions and their validation within a well-documented observing period (the ESCOMPTE campaign). Simultaneous water vapor radiometer, solar spectrometer, Raman lidar and radiosonde data are used for comparison and validation. In this paper, we highlight the motivation, issues and describe the GPS field experiment. Some first results of integrated water vapor retrievals from GPS and the other sensing techniques are presented. The strategies for GPS data processing and tomographic inversions are discussed.

  14. Optical detection of explosives: spectral signatures for the explosive bouquet

    Science.gov (United States)

    Osborn, Tabetha; Kaimal, Sindhu; Causey, Jason; Burns, William; Reeve, Scott

    2009-05-01

    Research with canines suggests that sniffer dogs alert not on the odor from a pure explosive, but rather on a set of far more volatile species present in an explosive as impurities. Following the explosive trained canine example, we have begun examining the vapor signatures for many of these volatile impurities utilizing high resolution spectroscopic techniques in several molecular fingerprint regions. Here we will describe some of these high resolution measurements and discuss strategies for selecting useful spectral signature regions for individual molecular markers of interest.

  15. Biodegradation of vapor-phase toluene in unsaturated porous media: Column experiments

    International Nuclear Information System (INIS)

    Khan, Ali M.; Wick, Lukas Y.; Harms, Hauke; Thullner, Martin

    2016-01-01

    Biodegradation of organic chemicals in the vapor phase of soils and vertical flow filters has gained attention as promising approach to clean up volatile organic compounds (VOC). The drivers of VOC biodegradation in unsaturated systems however still remain poorly understood. Here, we analyzed the processes controlling aerobic VOC biodegradation in a laboratory setup mimicking the unsaturated zone above a shallow aquifer. The setup allowed for diffusive vapor-phase transport and biodegradation of three VOC: non-deuterated and deuterated toluene as two compounds of highly differing biodegradability but (nearly) identical physical and chemical properties, and MTBE as (at the applied experimental conditions) non-biodegradable tracer and internal control. Our results showed for toluene an effective microbial degradation within centimeter VOC transport distances despite high gas-phase diffusivity. Degradation rates were controlled by the reactivity of the compounds while oxic conditions were found everywhere in the system. This confirms hypotheses that vadose zone biodegradation rates can be extremely high and are able to prevent the outgassing of VOC to the atmosphere within a centimeter range if compound properties and site conditions allow for sufficiently high degradation rates. - Highlights: • The column setup allows resolving vapor-phase VOC concentration gradients at cm scale resolution. • Vapor-phase and liquid-phase concentrations are measured simultaneously. • Isotopically labelled VOC was used as reference species of low biodegradability. • Biodegradation rates in the unsaturated zone can be very high and act at a cm scale. • Unsaturated material can be an effective bio-barrier avoiding biodegradable VOC emissions. - Microbial degradation activity can be sufficient to remove VOC from unsaturated porous media after a few centimeter of vapor-phase diffusive transport and mayeffectively avoid atmospheric emissions.

  16. An Exploratory Human Laboratory Experiment Evaluating Vaporized Cannabis in the Treatment of Neuropathic Pain From Spinal Cord Injury and Disease.

    Science.gov (United States)

    Wilsey, Barth; Marcotte, Thomas D; Deutsch, Reena; Zhao, Holly; Prasad, Hannah; Phan, Amy

    2016-09-01

    Using 8-hour human laboratory experiments, we evaluated the analgesic efficacy of vaporized cannabis in patients with neuropathic pain related to injury or disease of the spinal cord, most of whom were experiencing pain despite traditional treatment. After obtaining baseline data, 42 participants underwent a standardized procedure for inhaling 4 puffs of vaporized cannabis containing either placebo, 2.9%, or 6.7% delta 9-THC on 3 separate occasions. A second dosing occurred 3 hours later; participants chose to inhale 4 to 8 puffs. This flexible dosing was used to attempt to reduce the placebo effect. Using an 11-point numerical pain intensity rating scale as the primary outcome, a mixed effects linear regression model showed a significant analgesic response for vaporized cannabis. When subjective and psychoactive side effects (eg, good drug effect, feeling high, etc) were added as covariates to the model, the reduction in pain intensity remained significant above and beyond any effect of these measures (all P analgesic potency, the lower dose appears to offer the best risk-benefit ratio in patients with neuropathic pain associated with injury or disease of the spinal cord. A crossover, randomized, placebo-controlled human laboratory experiment involving administration of vaporized cannabis was performed in patients with neuropathic pain related to spinal cord injury and disease. This study supports consideration of future research that would include longer duration studies over weeks to months to evaluate the efficacy of medicinal cannabis in patients with central neuropathic pain. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

  17. Research on boiling liquid expanding vapour explosions

    Energy Technology Data Exchange (ETDEWEB)

    McDevitt, C.A.; Steward, F.R.; Venart, J.E.S.

    A boiling liquid expanding vapor explosion (BLEVE) is due to rapid boiling and expansion, with no ignition or chemical reaction involved. Research is being conducted to examine such questions as under what conditions tanks and their contents undergo BLEVE, what are the characteristics of tanks affected by BLEVE, and what alterations in tank design can be made to minimize the likelihood of BLEVEs. Experiments have been done with both propane and freon, using commercially available one-liter propane cylinders. Outdoor tests were conducted and designed to have the tank fail at a particular set of internal conditions. High speed photography was used to record the explosion, and computerized monitoring equipment to record temperature and pressure data. Tests were run to attempt to determine the relationship between temperature and BLEVEs, and to test the possibility that the occurrence of a BLEVE depends on the amount of vapor that could be produced when the tank was ruptured. Discussion is made of the role of pressure waves and rarefaction waves in the explosion. It is concluded that the superheat temperature limit, theorized as the minimum temperature below which no BLEVE can occur, cannot be used to predict BLEVEs. It has been shown that BLEVEs can occur below this temperature. There appears to be a relationship between liquid temperature, liquid volume, and the energy required to drive the BLEVE. Fireballs may occur after a BLEVE of flammable material, but are not part of the tank destruction. Rupture location (vapor vs liquid space) appears to have no effect on whether a container will undergo a BLEVE. 7 refs., 7 figs., 1 tab.

  18. Chemical Explosion Experiments to Improve Nuclear Test Monitoring - Developing a New Paradigm for Nuclear Test Monitoring with the Source Physics Experiments (SPE)

    International Nuclear Information System (INIS)

    Snelson, Catherine M.; Abbott, Robert E.; Broome, Scott T.; Mellors, Robert J.; Patton, Howard J.; Sussman, Aviva J.; Townsend, Margaret J.; Walter, William R.

    2013-01-01

    A series of chemical explosions, called the Source Physics Experiments (SPE), is being conducted under the auspices of the U.S. Department of Energy's National Nuclear Security Administration (NNSA) to develop a new more physics-based paradigm for nuclear test monitoring. Currently, monitoring relies on semi-empirical models to discriminate explosions from earthquakes and to estimate key parameters such as yield. While these models have been highly successful monitoring established test sites, there is concern that future tests could occur in media and at scale depths of burial outside of our empirical experience. This is highlighted by North Korean tests, which exhibit poor performance of a reliable discriminant, mb:Ms (Selby et al., 2012), possibly due to source emplacement and differences in seismic responses for nascent and established test sites. The goal of SPE is to replace these semi-empirical relationships with numerical techniques grounded in a physical basis and thus applicable to any geologic setting or depth

  19. Numerical Simulation and Experimental Study on Formation of High Concentration of H2 Generated by Gas Explosion

    Directory of Open Access Journals (Sweden)

    Lei Baiwei

    2016-10-01

    Full Text Available In coal mine fire rescues, if the abnormal increase of gas concentration occurs, it is the primary thing to analyze the reasons and identify sources of the abnormal forming, which is also the basis of judge the combustion state of fire area and formulate proper fire reliefs. Nowadays, related researches have recognized the methane explosion as the source of high concentration of H2 formation, but there are few studies about the conditions and reaction mechanism of gas explosion generating high concentration of H2.Therefore, this paper uses the chemical kinetic calculation software, ChemKin, and the 20L spherical explosion experimental device to simulate the generating process and formation conditions of H2 in gas explosion. The experimental results show that: the decomposition of water vapor is the main base element reaction (R84 which leads to the generation of H2.The free radical H is the key factor to influence the formation of H2 generated from gas explosion. With the gradual increase of gas explosion concentration, the explosive reaction becomes more incomplete, and then the generating quantity of H2 increases gradually. Experimental results of 20L spherical explosion are consistent with the change trend about simulation results, which verifies the accuracy of simulation analysis. The results of explosion experiments show that when gas concentration is higher than 9%, the incomplete reaction of methane explosion increases which leads to the gradual increase of H2 formation.

  20. Wireless sensor for detecting explosive material

    Science.gov (United States)

    Lamberti, Vincent E; Howell, Jr., Layton N; Mee, David K; Sepaniak, Michael J

    2014-10-28

    Disclosed is a sensor for detecting explosive devices. The sensor includes a ferromagnetic metal and a molecular recognition reagent coupled to the ferromagnetic metal. The molecular recognition reagent is operable to expand upon absorption of vapor from an explosive material such that the molecular recognition reagent changes a tensile stress upon the ferromagnetic metal. The explosive device is detected based on changes in the magnetic switching characteristics of the ferromagnetic metal caused by the tensile stress.

  1. An Exploratory Human Laboratory Experiment Evaluating Vaporized Cannabis in the Treatment of Neuropathic Pain from Spinal Cord Injury and Disease

    Science.gov (United States)

    Wilsey, Barth; Marcotte, Thomas D.; Deutsch, Reena; Zhao, Holly; Prasad, Hannah; Phan, Amy

    2016-01-01

    Using eight hour human laboratory experiments, we evaluated the analgesic efficacy of vaporized cannabis in patients with neuropathic pain related to injury or disease of the spinal cord, the majority of whom were experiencing pain despite traditional treatment. After obtaining baseline data, 42 participants underwent a standardized procedure for inhaling 4 puffs of vaporized cannabis containing either placebo, 2.9%, or 6.7% delta-9-tetrahydrocannabinol on three separate occasions. A second dosing occurred 3 hours later; participants chose to inhale 4 to 8 puffs. This flexible dosing was utilized to attempt to reduce the placebo effect. Using an 11-point numerical pain intensity rating scale as the primary outcome, a mixed effects linear regression model demonstrated a significant analgesic response for vaporized cannabis. When subjective and psychoactive side effects (e.g., good drug effect, feeling high, etc.) were added as covariates to the model, the reduction in pain intensity remained significant above and beyond any effect of these measures (all p<0.0004). Psychoactive and subjective effects were dose dependent. Measurement of neuropsychological performance proved challenging because of various disabilities in the population studied. As the two active doses did not significantly differ from each other in terms of analgesic potency, the lower dose appears to offer the best risk-benefit ratio in patients with neuropathic pain associated with injury or disease of the spinal cord. PMID:27286745

  2. Vapor Compression and Thermoelectric Heat Pumps for a Cascade Distillation Subsystem: Design and Experiment

    Science.gov (United States)

    Erickson, Lisa R.; Ungar, Eugene K.

    2012-01-01

    Humans on a spacecraft require significant amounts of water for drinking, food, hydration, and hygiene. Maximizing the reuse of wastewater while minimizing the use of consumables is critical for long duration space exploration. One of the more promising consumable-free methods of reclaiming wastewater is the distillation/condensation process used in the Cascade Distillation Subsystem (CDS). The CDS heats wastewater to the point of vaporization then condenses and cools the resulting water vapor. The CDS wastewater flow requires heating for evaporation and the product water flow requires cooling for condensation. Performing the heating and cooling processes separately would require two separate units, each of which would demand large amounts of electrical power. Mass, volume, and power efficiencies can be obtained by heating the wastewater and cooling the condensate in a single heat pump unit. The present work describes and compares two competing heat pump methodologies that meet the needs of the CDS: 1) a series of mini compressor vapor compression cycles and 2) a thermoelectric heat exchanger. In the paper, the CDS system level requirements are outlined, the designs of the two heat pumps are described in detail, and the results of heat pump analysis and performance tests are provided. The mass, volume, and power requirement for each heat pump option is compared and the advantages and disadvantages of each system are listed.

  3. Vapor Compression and Thermoelectric Heat Pump Heat Exchangers for a Condensate Distillation System: Design and Experiment

    Science.gov (United States)

    Erickson, Lisa R.; Ungar, Eugene K.

    2013-01-01

    Maximizing the reuse of wastewater while minimizing the use of consumables is critical in long duration space exploration. One of the more promising methods of reclaiming urine is the distillation/condensation process used in the cascade distillation system (CDS). This system accepts a mixture of urine and toxic stabilizing agents, heats it to vaporize the water and condenses and cools the resulting water vapor. The CDS wastewater flow requires heating and its condensate flow requires cooling. Performing the heating and cooling processes separately requires two separate units, each of which would require large amounts of electrical power. By heating the wastewater and cooling the condensate in a single heat pump unit, mass, volume, and power efficiencies can be obtained. The present work describes and compares two competing heat pump methodologies that meet the needs of the CDS: 1) a series of mini compressor vapor compression cycles and 2) a thermoelectric heat exchanger. In the paper, the system level requirements are outlined, the designs of the two heat pumps are described in detail, and the results of heat pump performance tests are provided. A summary is provided of the heat pump mass, volume and power trades and a selection recommendation is made.

  4. Small scale thermal violence experiments for combined insensitive high explosive and booster materials

    Energy Technology Data Exchange (ETDEWEB)

    Rae, Philip J [Los Alamos National Laboratory; Bauer, Clare L [AWE, UK; Stennett, C [DCMT SHRIVENHAM, UK; Flower, H M [AWE, UK

    2010-01-01

    A small scale cook-off experiment has been designed to provide a violence metric for both booster and IHE materials, singly and in combination. The experiment has a simple, axisymmetric geometry provided by a 10 mm internal diameter cylindrical steel confinement up to 80 mm in length. Heating is applied from one end of the sample length creating pseudo 1-D heating profile and a thermal gradient across the sample(s). At the opposite end of the confinement to the heating block, a machined groove provides a point of rupture that generates a cylindrical fragment. The displacement of the external face of the fragment is detected by Heterodyne Velocimetry. Proof of concept experiments are reported focusing on HMX and TATB formulations, and are described in relation to confinement, ullage and heating profile. The development of a violence metric, based upon fragment velocity records is discussed.

  5. The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects,High Explosive Experiments, and High Explosive Construction Activities Volume 1 of 3

    Energy Technology Data Exchange (ETDEWEB)

    Beck Colleen M,Edwards Susan R.,King Maureen L.

    2011-09-01

    This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

  6. The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects,High Explosive Experiments, and High Explosive Construction Activities Volume 2 of 3

    Energy Technology Data Exchange (ETDEWEB)

    Beck Colleen M.,Edwards Susan R.,King Maureen L.

    2011-09-01

    This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

  7. The Off-Site Plowshare and Vela Uniform Programs: Assessing Potential Environmental Liabilities through an Examination of Proposed Nuclear Projects,High Explosive Experiments, and High Explosive Construction Activities Volume 3 of 3

    Energy Technology Data Exchange (ETDEWEB)

    Beck Colleen M.,Edwards Susan R.,King Maureen L.

    2011-09-01

    This document presents the results of nearly six years (2002-2008) of historical research and field studies concerned with evaluating potential environmental liabilities associated with U.S. Atomic Energy Commission projects from the Plowshare and Vela Uniform Programs. The Plowshare Program's primary purpose was to develop peaceful uses for nuclear explosives. The Vela Uniform Program focused on improving the capability of detecting, monitoring and identifying underground nuclear detonations. As a result of the Project Chariot site restoration efforts in the early 1990s, there were concerns that there might be other project locations with potential environmental liabilities. The Desert Research Institute conducted archival research to identify projects, an analysis of project field activities, and completed field studies at locations where substantial fieldwork had been undertaken for the projects. Although the Plowshare and Vela Uniform nuclear projects are well known, the projects that are included in this research are relatively unknown. They are proposed nuclear projects that were not executed, proposed and executed high explosive experiments, and proposed and executed high explosive construction activities off the Nevada Test Site. The research identified 170 Plowshare and Vela Uniform off-site projects and many of these had little or no field activity associated with them. However, there were 27 projects that merited further investigation and field studies were conducted at 15 locations.

  8. Validation of the containment code Sirius: interpretation of an explosion experiment on a scale model

    International Nuclear Information System (INIS)

    Blanchet, Y.; Obry, P.; Louvet, J.; Deshayes, M.; Phalip, C.

    1979-01-01

    The explicit 2-D axisymmetric Langrangian code SIRIUS, developed at the CEA/DRNR, Cadarache, deals with transient compressive flows in deformable primary tanks with more or less complex internal component geometries. This code has been subjected to a two-year intensive validation program on scale model experiments and a number of improvements have been incorporated. This paper presents a recent calculation of one of these experiments using the SIRIUS code, and the comparison with experimental results shows the encouraging possibilities of this Lagrangian code

  9. Piezoelectric trace vapor calibrator

    International Nuclear Information System (INIS)

    Verkouteren, R. Michael; Gillen, Greg; Taylor, David W.

    2006-01-01

    The design and performance of a vapor generator for calibration and testing of trace chemical sensors are described. The device utilizes piezoelectric ink-jet nozzles to dispense and vaporize precisely known amounts of analyte solutions as monodisperse droplets onto a hot ceramic surface, where the generated vapors are mixed with air before exiting the device. Injected droplets are monitored by microscope with strobed illumination, and the reproducibility of droplet volumes is optimized by adjustment of piezoelectric wave form parameters. Complete vaporization of the droplets occurs only across a 10 deg. C window within the transition boiling regime of the solvent, and the minimum and maximum rates of trace analyte that may be injected and evaporated are determined by thermodynamic principles and empirical observations of droplet formation and stability. By varying solution concentrations, droplet injection rates, air flow, and the number of active nozzles, the system is designed to deliver--on demand--continuous vapor concentrations across more than six orders of magnitude (nominally 290 fg/l to 1.05 μg/l). Vapor pulses containing femtogram to microgram quantities of analyte may also be generated. Calibrated ranges of three explosive vapors at ng/l levels were generated by the device and directly measured by ion mobility spectrometry (IMS). These data demonstrate expected linear trends within the limited working range of the IMS detector and also exhibit subtle nonlinear behavior from the IMS measurement process

  10. Modules for Experiments in Stellar Astrophysics (MESA): Convective Boundaries, Element Diffusion, and Massive Star Explosions

    OpenAIRE

    Paxton, Bill; Schwab, Josiah; Bauer, Evan B.; Bildsten, Lars; Blinnikov, Sergei; Duffell, Paul; Farmer, R.; Goldberg, Jared A.; Marchant, Pablo; Sorokina, Elena; Thoul, Anne; Townsend, Richard H. D.; Timmes, F. X.

    2017-01-01

    We update the capabilities of the software instrument Modules for Experiments in Stellar Astrophysics (MESA) and enhance its ease of use and availability. Our new approach to locating convective boundaries is consistent with the physics of convection, and yields reliable values of the convective core mass during both hydrogen and helium burning phases. Stars with $M

  11. Stellar explosion

    International Nuclear Information System (INIS)

    Suraud, E.

    1987-01-01

    What is the energy source and which physical processes are powerful enough to generate this explosion which scatters the star. The knowledge progress of very dense matter allows the scenario reconstitution. An instability in the star core which is developing during milliseconds is the cause of this explosion [fr

  12. Aspects regarding explosion risk assessment

    Directory of Open Access Journals (Sweden)

    Părăian Mihaela

    2017-01-01

    Full Text Available Explosive risk occurs in all activities involving flammable substances in the form of gases, vapors, mists or dusts which, in mixture with air, can generate an explosive atmosphere. As explosions can cause human losses and huge material damage, the assessment of the explosion risk and the establishment of appropriate measures to reduce it to acceptable levels according to the standards and standards in force is of particular importance for the safety and health of people and goods.There is no yet a recognized method of assessing the explosion risk, but regardless of the applied method, the likelihood of an explosive atmosphere occurrence has to be determined, together with the occurrence of an efficient ignition source and the magnitude of foreseeable consequences. In assessment processes, consequences analysis has a secondary importance since it’s likely that explosions would always involve considerable damage, starting from important material damages and up to human damages that could lead to death.The purpose of the work is to highlight the important principles and elements to be taken into account for a specific risk assessment. An essential element in assessing the risk of explosion in workplaces where explosive atmospheres may occur is technical installations and personal protective equipment (PPE that must be designed, manufactured, installed and maintained so that they cannot generate a source of ignition. Explosion prevention and protection requirements are governed by specific norms and standards, and a main part of the explosion risk assessment is related to the assessment of the compliance of the equipment / installation with these requirements.

  13. Droplet solidification and the potential for steam explosions

    International Nuclear Information System (INIS)

    Epstein, M.; Fauske, H.K.; Luangdilok, W.

    2009-01-01

    It is well known that under certain circumstances a mixture of coarse-hot (molten) drops in water formed from pouring a hot melt into water explodes. This so-called 'steam explosion' is generally believed to involve steam-bubble-collapse-induced fine fragmentation of the melt drops and concomitant water vaporization on a timescale that is short compared with the steam pressure relief time. Motivated by the idea put forth by Okkonen and Sehgal that rapid solidification would render UO 2 -containing (Corium) melt drops stiff and resistant to the steam-bubble-collapse-induced fragmentation required to support an explosion, here we combine solidification theory with an available theory of the stability of thin, submerged crusts subject to acceleration to predict the 'cutoff time' beyond which melt-drop fragmentation is suppressed by crust cover rigidity. Illustration calculations show that the cutoff time for Corium melt drops in water is a fraction of a second and probably shorter than the time it takes to form the explosion-prerequisite-coarse-premixture configuration of melt drops in water, while the opposite is true for the molten aluminum oxide/water system for which the window of opportunity for an explosion is predicted to be several seconds. These theoretical findings are consistent with early experiments that revealed molten uranium oxide or Corium pours into water to be non-explosive and that produced steam explosions upon pouring molten aluminum oxide into water. Also in this paper, the recent TROI Corium/water interaction experiments are examined and it is concluded that they do not contravene the earlier experimental observations that the pouring of prototypical Corium mixtures into water does not result in steam explosions with destructive potential. (author)

  14. DNA typing from skeletal remains following an explosion in a military fort--first experience in Ecuador (South-America).

    Science.gov (United States)

    González-Andrade, Fabricio; Sánchez, Dora

    2005-10-01

    We present individual body identification efforts, to identify skeletal remains and relatives of missing persons of an explosion took place inside one of the munitions recesses of the Armoured Brigade of the Galapagos Armoured Cavalry, in the city of Riobamba, Ecuador, on Wednesday, November 20, 2002. Nineteen samples of bone remains and two tissue samples (a blood stain on a piece of fabric) from the zero zone were analysed. DNA extraction was made by Isoamilic Phenol-Chloroform-Alcohol, and proteinase K. We increased PCR cycles to identify DNA from bones to 35 cycles in some cases. An ABI 310 sequencer was used. Determination of the fragment size and the allelic designation of the different loci was carried out by comparison with the allelic ladders of the PowerPlex 16 kit and Gene Scan Analysis Software programme. Five possible family groups were established and were compared with the profiles found. Classical Bayesian methods were used to calculate the Likelihood Ratio and it was possible to identify five different genetic profiles in our country. This paper is important because is a novel experience for our forensic services, because this was the first time DNA had been used as an identification method in disasters, and it was validated by Ecuadorian justice like a very effective method.

  15. Phenomenological modelling of steam explosions

    International Nuclear Information System (INIS)

    Corradini, M.L.; Drumheller, D.S.

    1980-01-01

    During a hypothetical core meltdown accident, an important safety issue to be addressed is the potential for steam explosions. This paper presents analysis and modelling of experimental results. There are four observations that can be drawn from the analysis: (1) vapor explosions are suppressed by noncondensible gases generated by fuel oxidation, by high ambient pressure, and by high water temperatures; (2) these effects appear to be trigger-related in that an explosion can again be induced in some cases by increasing the trigger magnitude; (3) direct fuel liquid-coolant liquid contact can explain small scale fuel fragmentation; (4) heat transfer during the expansion phase of the explosion can reduce the work potential

  16. Modules for Experiments in Stellar Astrophysics (MESA): Convective Boundaries, Element Diffusion, and Massive Star Explosions

    Science.gov (United States)

    Paxton, Bill; Schwab, Josiah; Bauer, Evan B.; Bildsten, Lars; Blinnikov, Sergei; Duffell, Paul; Farmer, R.; Goldberg, Jared A.; Marchant, Pablo; Sorokina, Elena; Thoul, Anne; Townsend, Richard H. D.; Timmes, F. X.

    2018-02-01

    We update the capabilities of the software instrument Modules for Experiments in Stellar Astrophysics (MESA) and enhance its ease of use and availability. Our new approach to locating convective boundaries is consistent with the physics of convection, and yields reliable values of the convective-core mass during both hydrogen- and helium-burning phases. Stars with Meffects of Rayleigh-Taylor instabilities that, in combination with the coupling to a public version of the STELLA radiation transfer instrument, creates new avenues for exploring Type II supernova properties. These capabilities are exhibited with exploratory models of pair-instability supernovae, pulsational pair-instability supernovae, and the formation of stellar-mass black holes. The applicability of MESA is now widened by the capability to import multidimensional hydrodynamic models into MESA. We close by introducing software modules for handling floating point exceptions and stellar model optimization, as well as four new software tools - MESA-Web, MESA-Docker, pyMESA, and mesastar.org - to enhance MESA's education and research impact.

  17. Measurement of air and VOC vapor fluxes during gas-driven soil remediation: bench-scale experiments.

    Science.gov (United States)

    Kim, Heonki; Kim, Taeyun; Shin, Seungyeop; Annable, Michael D

    2012-09-04

    In this laboratory study, an experimental method was developed for the quantitative analyses of gas fluxes in soil during advective air flow. One-dimensional column and two- and three-dimensional flow chamber models were used in this study. For the air flux measurement, n-octane vapor was used as a tracer, and it was introduced in the air flow entering the physical models. The tracer (n-octane) in the gas effluent from the models was captured for a finite period of time using a pack of activated carbon, which then was analyzed for the mass of n-octane. The air flux was calculated based on the mass of n-octane captured by the activated carbon and the inflow concentration. The measured air fluxes are in good agreement with the actual values for one- and two-dimensional model experiments. Using both the two- and three-dimensional models, the distribution of the air flux at the soil surface was measured. The distribution of the air flux was found to be affected by the depth of the saturated zone. The flux and flux distribution of a volatile contaminant (perchloroethene) was also measured by using the two-dimensional model. Quantitative information of both air and contaminant flux may be very beneficial for analyzing the performance of gas-driven subsurface remediation processes including soil vapor extraction and air sparging.

  18. Simulating intracrater ash recycling during mid-intensity explosive activity: high temperature laboratory experiments on natural basaltic ash

    Science.gov (United States)

    D'Oriano, Claudia; Pompilio, Massimo; Bertagnini, Antonella; Cioni, Raffaello; Pichavant, Michel

    2010-05-01

    Direct observations of mid-intensity eruptions, in which a huge amount of ash is generated, indicate that ash recycling is quite common. The recognition of juvenile vs. recycled fragments is not straightforward, and no unequivocal, widely accepted criteria exist to support this. The presence of recycled glassy fragments can hide primary magmatic information, introducing bias in the interpretations of the ongoing magmatic and volcanic activity. High temperature experiments were performed at atmospheric pressure on natural samples to investigate the effects of reheating on morphology, texture and composition of volcanic ash. Experiments simulate the transformation of juvenile glassy fragments that, falling into the crater or in the upper part of the conduit, are recycled by following explosions. Textural and compositional modifications obtained in laboratory are compared with similar features observed in natural samples in order to identify some main general criteria to be used for the discrimination of recycled material. Experiments were carried out on tephra produced during Strombolian activity, fire fountains and continuous ash emission at Etna, Stromboli and Vesuvius. Coarse glassy clasts were crushed in a nylon mortar in order to create an artificial ash, and then sieved to select the size interval of 1-0.71 mm. Ash shards were put in a sealed or open quartz tube, in order to prevent or to reproduce effects of air oxidation. The tube was suspended in a HT furnace at INGV-Pisa and kept at different temperatures (up to to 1110°C) for increasing time (0.5-12 hours). Preliminary experiments were also performed under gas flux conditions. Optical and electron microscope observations indicate that high temperature and exposure to the air induce large modifications on clast surface, ranging from change in color, to incipient plastic deformation till complete sintering. Significant change in color of clasts is strictly related to the presence of air, irrespective of

  19. Physical model for vaporization

    OpenAIRE

    Garai, Jozsef

    2006-01-01

    Based on two assumptions, the surface layer is flexible, and the internal energy of the latent heat of vaporization is completely utilized by the atoms for overcoming on the surface resistance of the liquid, the enthalpy of vaporization was calculated for 45 elements. The theoretical values were tested against experiments with positive result.

  20. Filling high aspect ratio trenches by superconformal chemical vapor deposition: Predictive modeling and experiment

    Science.gov (United States)

    Wang, Wenjiao B.; Abelson, John R.

    2014-11-01

    Complete filling of a deep recessed structure with a second material is a challenge in many areas of nanotechnology fabrication. A newly discovered superconformal coating method, applicable in chemical vapor deposition systems that utilize a precursor in combination with a co-reactant, can solve this problem. However, filling is a dynamic process in which the trench progressively narrows and the aspect ratio (AR) increases. This reduces species diffusion within the trench and may drive the component partial pressures out of the regime for superconformal coating. We therefore derive two theoretical models that can predict the possibility for filling. First, we recast the diffusion-reaction equation for the case of a sidewall with variable taper angle. This affords a definition of effective AR, which is larger than the nominal AR due to the reduced species transport. We then derive the coating profile, both for superconformal and for conformal coating. The critical (most difficult) step in the filling process occurs when the sidewalls merge at the bottom of the trench to form the V shape. Experimentally, for the Mg(DMADB)2/H2O system and a starting AR = 9, this model predicts that complete filling will not be possible, whereas experimentally we do obtain complete filling. We then hypothesize that glancing-angle, long-range transport of species may be responsible for the better than predicted filling. To account for the variable range of species transport, we construct a ballistic transport model. This incorporates the incident flux from outside the structure, cosine law re-emission from surfaces, and line-of-sight transport between internal surfaces. We cast the transport probability between all positions within the trench into a matrix that represents the redistribution of flux after one cycle of collisions. Matrix manipulation then affords a computationally efficient means to determine the steady-state flux distribution and growth rate for a given taper angle. The

  1. Testing the equation of state and electrical conductivity of copper by the electrical wire explosion in air: Experiment and magnetohydrodynamic simulation

    International Nuclear Information System (INIS)

    Barysevich, A. E.; Cherkas, S. L.

    2011-01-01

    We perform experiments on testing the equations of state and electrical conductivity of copper in three different regimes of copper wire electrical explosion, when the inserted energy (i) is slightly exceeded, (ii) is approximately equal, and (iii) is substantially exceeded the energy needed for the wire complete evaporation. Magnetohydrodynamic simulation is performed. The results predicted by the two different equations of state are compared with the experiment. Empirical expression for the copper electrical conductivity is presented. Parameters in this expression is fit on every of two equations of state. Map of copper conductivity is plotted.

  2. Glass produced by underground nuclear explosions

    International Nuclear Information System (INIS)

    Schwartz, L.; Piwinskii, A.; Ryerson, F.; Tewes, H.; Beiriger, W.

    1983-01-01

    Detonation of an underground nuclear explosive produces a strong shock wave which propagates spherically outward, vaporizing the explosive and nearby rock and melting, the surrounding rock. The vaporized material expands adiabatically, forming a cavity. As the energy is dissipated during the cavity formation process, the explosive and rock debris condense and mix with the melted rock. The melt flows to the bottom of the cavity where it is quenched by fractured rock fragments falling from above as the cavity collapses. Measurements indicate that about 740 tonnes of rock and/or soil are melted for every kiloton (10 12 calories) of explosive energy, or about 25% of the explosive energy goes to melting rock. The resulting glass composition reflects the composition of the unaltered rock with explosive debris. The appearance ranges from white pumice to dense, dark lava. The bulk composition and color vary with the amount of explosive iron incorporated into the glass. The refractory explosion products are mixed with the solidified melt, although the degree of mixing is variable. Electron microprobe studies of glasses produced by Rainier in welded tuff have produced the following results: glasses are dehydrated relative to the host media, glasses are extremely heterogeneous on a 20 μm scale, a ubiquitous feature is the presence of dark marble-cake regions in the glass, which were locally enriched in iron and may be related to the debris, optically amorphous regions provide evidence of shock melting, only limited major element redistribution and homogenization occur within the cavity

  3. Determination of Mercury in Milk by Cold Vapor Atomic Fluorescence: A Green Analytical Chemistry Laboratory Experiment

    Science.gov (United States)

    Armenta, Sergio; de la Guardia, Miguel

    2011-01-01

    Green analytical chemistry principles were introduced to undergraduate students in a laboratory experiment focused on determining the mercury concentration in cow and goat milk. In addition to traditional goals, such as accuracy, precision, sensitivity, and limits of detection in method selection and development, attention was paid to the…

  4. The effect of explosive percentage on underwater explosion energy release of hexanitrohexaazaisowurtzitane and octogen based aluminized explosives

    Directory of Open Access Journals (Sweden)

    Qingjie Jiao

    2018-03-01

    Full Text Available To control the explosion energy output by optimizing explosive components is a key requirement in a number of different application areas. The effect of different Al/O Ratio on underwater explosion of aluminized explosives has been studied detailedly. However, the effect of explosive percentage in the same Al/O Ratio is rarely researched, especially for Hexanitrohexaazaisowurtzitane (CL-20 based aluminized explosives. In this study, we performed the underwater explosion experiments with 1.2-kilogram explosives in order to investigate the explosion energy released from CL-20 and Octogen (HMX based aluminized explosives. The percentage of the explosive varied from 5% to 30% and it is shown that: the shockwave peak pressure (pm grows gradually; shock wave energy (Es continues increasing, bubble energy (Eb increases then decreases peaking at 15% for both formulas, and the total energy (E and energy release rate (η peak at 20% for CL-20 and 15% for HMX. This paper outlines the physical mechanism of Eb change under the influence of an aluminium initial reaction temperature and reaction active detonation product percentage coupling. The result shows that CL-20 is superior as a new high explosive and has promising application prospects in the regulation of explosive energy output for underwater explosives.

  5. The effect of explosive percentage on underwater explosion energy release of hexanitrohexaazaisowurtzitane and octogen based aluminized explosives

    Science.gov (United States)

    Jiao, Qingjie; Wang, Qiushi; Nie, Jianxin; Guo, Xueyong; Zhang, Wei; Fan, Wenqi

    2018-03-01

    To control the explosion energy output by optimizing explosive components is a key requirement in a number of different application areas. The effect of different Al/O Ratio on underwater explosion of aluminized explosives has been studied detailedly. However, the effect of explosive percentage in the same Al/O Ratio is rarely researched, especially for Hexanitrohexaazaisowurtzitane (CL-20) based aluminized explosives. In this study, we performed the underwater explosion experiments with 1.2-kilogram explosives in order to investigate the explosion energy released from CL-20 and Octogen (HMX) based aluminized explosives. The percentage of the explosive varied from 5% to 30% and it is shown that: the shockwave peak pressure (pm) grows gradually; shock wave energy (Es) continues increasing, bubble energy (Eb) increases then decreases peaking at 15% for both formulas, and the total energy (E) and energy release rate (η) peak at 20% for CL-20 and 15% for HMX. This paper outlines the physical mechanism of Eb change under the influence of an aluminium initial reaction temperature and reaction active detonation product percentage coupling. The result shows that CL-20 is superior as a new high explosive and has promising application prospects in the regulation of explosive energy output for underwater explosives.

  6. Optimal dynamic detection of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Moore, David Steven [Los Alamos National Laboratory; Mcgrane, Shawn D [Los Alamos National Laboratory; Greenfield, Margo T [Los Alamos National Laboratory; Scharff, R J [Los Alamos National Laboratory; Rabitz, Herschel A [PRINCETON UNIV; Roslund, J [PRINCETON UNIV

    2009-01-01

    The detection of explosives is a notoriously difficult problem, especially at stand-off distances, due to their (generally) low vapor pressure, environmental and matrix interferences, and packaging. We are exploring optimal dynamic detection to exploit the best capabilities of recent advances in laser technology and recent discoveries in optimal shaping of laser pulses for control of molecular processes to significantly enhance the standoff detection of explosives. The core of the ODD-Ex technique is the introduction of optimally shaped laser pulses to simultaneously enhance sensitivity of explosives signatures while reducing the influence of noise and the signals from background interferents in the field (increase selectivity). These goals are being addressed by operating in an optimal nonlinear fashion, typically with a single shaped laser pulse inherently containing within it coherently locked control and probe sub-pulses. With sufficient bandwidth, the technique is capable of intrinsically providing orthogonal broad spectral information for data fusion, all from a single optimal pulse.

  7. General phenomenology of underground nuclear explosions; Phenomenologie generale des explosions nucleaires souterraines

    Energy Technology Data Exchange (ETDEWEB)

    Derlich, S; Supiot, F [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    An essentially qualitatively description is given of the phenomena related to underground nuclear explosions (explosion of a single unit, of several units in line, and simultaneous explosions). In the first chapter are described the phenomena which are common to contained explosions and to explosions forming craters (formation and propagation of a shock-wave causing the vaporization, the fusion and the fracturing of the medium). The second chapter describes the phenomena related to contained explosions (formation of a cavity with a chimney). The third chapter is devoted to the phenomenology of test explosions which form a crater; it describes in particular the mechanism of formation and the different types of craters as a function of the depth of the explosion and of the nature of the ground. The aerial phenomena connected with explosions which form a crater: shock wave in the air and focussing at a large distance, and dust clouds, are also dealt with. (authors) [French] On donne une description essentiellement qualitative des phenomenes lies aux explosions nucleaires souterraines (explosion d'un seul engin, d'engins en ligne et explosions simultanees). Dans un premier chapitre sont decrits les phenomenes communs aux explosions contenues et aux explosions formant un cratere (formation et propagation d'une onde de choc provoquant la vaporisation, la fusion et la fracturation du milieu). Le deuxieme chapitre decrit les phenomenes lies aux tirs contenus (formation d'une cavite et d'une cheminee). Le troisieme chapitre est consacre a la phenomenologie des tirs formant un cratere et decrit notamment le mecanisme de formation et les differents types de crateres en fonction de la profondeur d'explosion et de la nature du terrain. Les phenomenes aeriens lies aux explosions formant un cratere: onde de pression aerienne et focalisation a grande distance, nuages de poussieres, sont egalement abordes. (auteurs)

  8. The behavior limestone under explosive load

    Science.gov (United States)

    Orlov, M. Yu; Orlova, Yu N.; Bogomolov, G. N.

    2016-11-01

    Limestone behavior under explosive loading was investigated. The behavior of the limestone by the action of the three types of explosives, including granular, ammonite and emulsion explosives was studied in detail. The shape and diameter of the explosion craters were obtained. The observed fragments after the blast have been classified as large, medium and small fragments. Three full-scale experiments were carried out. The research results can be used as a qualitative test for the approbation of numerical methods.

  9. Temperature distribution analysis of tissue water vaporization during microwave ablation: experiments and simulations.

    Science.gov (United States)

    Ai, Haiming; Wu, Shuicai; Gao, Hongjian; Zhao, Lei; Yang, Chunlan; Zeng, Yi

    2012-01-01

    The temperature distribution in the region near a microwave antenna is a critical factor that affects the entire temperature field during microwave ablation of tissue. It is challenging to predict this distribution precisely, because the temperature in the near-antenna region varies greatly. The effects of water vaporisation and subsequent tissue carbonisation in an ex vivo porcine liver were therefore studied experimentally and in simulations. The enthalpy and high-temperature specific absorption rate (SAR) of liver tissues were calculated and incorporated into the simulation process. The accuracy of predictions for near-field temperatures in our simulations has reached the level where the average maximum error is less than 5°C. In addition, a modified thermal model that accounts for water vaporisation and the change in the SAR distribution pattern is proposed and validated with experiment. The results from this study may be useful in the clinical practice of microwave ablation and can be applied to predict the temperature field in surgical planning.

  10. Forward Model Studies of Water Vapor Using Scanning Microwave Radiometers, Global Positioning System, and Radiosondes during the Cloudiness Intercomparison Experiment

    International Nuclear Information System (INIS)

    Mattioli, Vinia; Westwater, Ed R.; Gutman, S.; Morris, Victor R.

    2005-01-01

    Brightness temperatures computed from five absorption models and radiosonde observations were analyzed by comparing them with measurements from three microwave radiometers at 23.8 and 31.4 GHz. Data were obtained during the Cloudiness Inter-Comparison experiment at the U.S. Department of Energy's Atmospheric Radiation Measurement Program's (ARM) site in North-Central Oklahoma in 2003. The radiometers were calibrated using two procedures, the so-called instantaneous ?tipcal? method and an automatic self-calibration algorithm. Measurements from the radiometers were in agreement, with less than a 0.4-K difference during clear skies, when the instantaneous method was applied. Brightness temperatures from the radiometer and the radiosonde showed an agreement of less than 0.55 K when the most recent absorption models were considered. Precipitable water vapor (PWV) computed from the radiometers were also compared to the PWV derived from a Global Positioning System station that operates at the ARM site. The instruments agree to within 0.1 cm in PWV retrieval

  11. Shock-to-detonation transition of RDX, HMX and NTO based composite high explosives: experiments and modelling

    International Nuclear Information System (INIS)

    Baudin, G; Roudot, M; Genetier, M; Mateille, P; Lefrançois, A

    2014-01-01

    HMX, RDX and NTO based cast-cured plastic bounded explosive (PBX) are widely used in insensitive ammunitions. Designing modern warheads needs robust and reliable models to compute shock ignition and detonation propagation inside PBX. Comparing to a pressed PBX, a cast-cured PBX is not porous and the hot-spots are mainly located at the grain-binder interface leading to a different burning behavior during shock-to-detonation transition. Here, we review the shock-to-detonation transition (SDT) and its modeling for cast-cured PBX containing HMX, RDX and NTO. Future direction is given in conclusion.

  12. Shock-to-detonation transition of RDX, HMX and NTO based composite high explosives: experiments and modelling

    Science.gov (United States)

    Baudin, G.; Roudot, M.; Genetier, M.; Mateille, P.; Lefrançois, A.

    2014-05-01

    HMX, RDX and NTO based cast-cured plastic bounded explosive (PBX) are widely used in insensitive ammunitions. Designing modern warheads needs robust and reliable models to compute shock ignition and detonation propagation inside PBX. Comparing to a pressed PBX, a cast-cured PBX is not porous and the hot-spots are mainly located at the grain-binder interface leading to a different burning behavior during shock-to-detonation transition. Here, we review the shock-to-detonation transition (SDT) and its modeling for cast-cured PBX containing HMX, RDX and NTO. Future direction is given in conclusion.

  13. Explosive simulants for testing explosive detection systems

    Science.gov (United States)

    Kury, John W.; Anderson, Brian L.

    1999-09-28

    Explosives simulants that include non-explosive components are disclosed that facilitate testing of equipment designed to remotely detect explosives. The simulants are non-explosive, non-hazardous materials that can be safely handled without any significant precautions. The simulants imitate real explosives in terms of mass density, effective atomic number, x-ray transmission properties, and physical form, including moldable plastics and emulsions/gels.

  14. Research on the fundamental process of thermal-hydraulic behaviors in severe accident. Vapor film collapse behavior on high temperature particle surface. JAERI's nuclear research promotion program, H10-027-3. Contract research

    International Nuclear Information System (INIS)

    Abe, Yutaka

    2002-03-01

    The experimental researches were conducted to study vapor film collapse behavior on high temperature melted core material coarsely mixed in the coolant under the film boiling condition. The film collapse is very important incipient incident of the trigger process for the vapor explosion in sever accident of nuclear reactor. In the experiment, pressure pulse was applied to the vapor film on a high temperature particle surface simulating melted core material to observed microscopic vapor film collapse behavior with a high-speed video camera of 40,500 fps. The particle surface temperature and pressure around the particle were simultaneously measured. The transition of the vapor film thickness and two-dimensional vapor-liquid interface movement and the velocity were estimated with visual data analysis technique, PIV and digital data analysis technique. Furthermore, heat conduction analysis was performed to estimate the vapor-liquid interfacial temperature with the measured temperature and estimated vapor film thickness. As the results, it was clarified that the vapor-liquid interface changed white from transparent view for all the experimental conditions. It is also clarified that the vapor-liquid interfacial temperature decreased under the saturation temperature when the pressure pulse arrive at the particle. The experimental facts indicates the possibility that the vapor film collapse occurs due to the liquid phase homogeneous moving toward the particle drove by the pressure reduction caused by the phase change inside the vapor film. (author)

  15. Research on the fundamental process of thermal-hydraulic behaviors in severe accident. Vapor film collapse behavior on high temperature particle surface. JAERI's nuclear research promotion program, H10-027-3. Contract research

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Yutaka [Tsukuba Univ., Institute of Engineering Mechanics and Systems, Tsukuba, Ibaraki (Japan)

    2002-03-01

    The experimental researches were conducted to study vapor film collapse behavior on high temperature melted core material coarsely mixed in the coolant under the film boiling condition. The film collapse is very important incipient incident of the trigger process for the vapor explosion in sever accident of nuclear reactor. In the experiment, pressure pulse was applied to the vapor film on a high temperature particle surface simulating melted core material to observed microscopic vapor film collapse behavior with a high-speed video camera of 40,500 fps. The particle surface temperature and pressure around the particle were simultaneously measured. The transition of the vapor film thickness and two-dimensional vapor-liquid interface movement and the velocity were estimated with visual data analysis technique, PIV and digital data analysis technique. Furthermore, heat conduction analysis was performed to estimate the vapor-liquid interfacial temperature with the measured temperature and estimated vapor film thickness. As the results, it was clarified that the vapor-liquid interface changed white from transparent view for all the experimental conditions. It is also clarified that the vapor-liquid interfacial temperature decreased under the saturation temperature when the pressure pulse arrive at the particle. The experimental facts indicates the possibility that the vapor film collapse occurs due to the liquid phase homogeneous moving toward the particle drove by the pressure reduction caused by the phase change inside the vapor film. (author)

  16. Explosive Pleuritis

    Directory of Open Access Journals (Sweden)

    Satish Kumar

    2012-01-01

    Full Text Available Pleural effusions associated with pneumonia (parapneumonic effusions are one of the most common causes of exudative pleural effusions in the world. Approximately 20 to 40% of patients hospitalized with pneumonia will have an accompanying pleural effusion. The term 'Explosive pleuritis' was originally described by Braman and Donat in 1986 as pleural effusions developing within hours of admission. We report a 38 years old male patient with minimal pleural effusion which progressed rapidly within one day to involve almost whole of the hemithorax. There were multiple loculations on ultrasonography of thorax. Pleural fluid was sero-sanguinous and revealed gram positive diplococcic. The patient improved with antibiotics and pigtail catheter drainage.

  17. Steam explosion triggering phenomena: stainless steel and corium-E simulants studied with a floodable arc melting apparatus

    International Nuclear Information System (INIS)

    Nelson, L.S.; Buxton, L.D.

    1978-05-01

    Laboratory-scale experiments on the thermal interaction of light water reactor core materials with water have been performed. Samples (10--35 g) of Type 304 stainless steel and Corium-E simulants were each flooded with approximately 1.5 litres of water to determine whether steam explosions would occur naturally. Many of the experiments also employed artificially induced pressure transients in an attempt to initiate steam explosions. Vigorous interactions were not observed when the triggering pulse was not applied, and for stainless steel the triggering pulse initiated only coarse fragmentation. Two-stage, pressure-producing interactions were triggered for an ''oxidic'' Corium-E simulant. An impulse-initiated gas release theory has been simulated to explain the initial sample fragmentation. Although the delayed second stage of the event is not fully understood, it does not appear to be readily explained with classical vapor explosion theory. Rather, some form of metastability of the melt seems to be involved

  18. FCI experiments and analysis. Contributions to basic understanding

    International Nuclear Information System (INIS)

    Corradini, M.L.; Cho, D.; Magallon, D.; Basu, S.

    1998-01-01

    Past safety analyses considered the hazard from vapor explosions in a conservative manner where engineering judgement and conservative analyses were used to estimate the likelihood of nuclear reactor containment failure from explosion-induced missile generation (alpha-mode failure). However, recent safety analyses may require less conservative methods to determine the hazard from vapor explosions; thus, one may need to consider more detailed scaling of vapor explosion energetics, considering fuel-coolant mixing and explosion propagation. The United States Nuclear Regulatory Commission is supporting a coordinated set of experiments to address this issue, given a lack of appropriate benchmark data and associated analyses. These experiments, KROTOS, WFCI and ZrEX are mutually complimentary and provide the first consistent set of data for FCI phenomena under controlled conditions for a wide range of simulant materials that approximate the fuel melt. The scaling logic for these tests is that essentially one-dimensional geometry with rigid constraints would maximize the explosion energetics for a given set of mixing conditions. Thus, only variations in the axial boundary conditions and fuel-coolant initial conditions (mass, composition and temperatures) can affect the mixing and energetics. Our hypothesis is that clear limits to energetics below thermodynamic values can be identified for these high temperature fuel melts along with fundamental understanding, which can aid in issue resolution. (author)

  19. Steam-explosion mitigation with polymer and surfactant additives

    International Nuclear Information System (INIS)

    Pineau, D.; Ranval, W.

    1996-02-01

    Vapor explosion (or MFCI for Molten Fuel-Coolant Interaction) is a phenomenon in which a hot liquid rapidly transfers its internal energy into a surrounding colder and more volatile liquid (the coolant) which vaporization is violent. One of the simplest coolant is water. However it was noticed that some particular additives in water could have a mitigative effect on this phenomenon. This paper deals with the description of polymeric and/or surfactant solutions and their ability to suppress vapor explosion. (authors). 24 refs., 5 figs

  20. Explosion approach for external safety assessment: a case study

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D. Michael; Halford, Ann [Germanischer Lloyd, Loughborough (United Kingdom); Mendes, Renato F. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2009-07-01

    Several questions related to the potential for explosions are explored as this became an important subject during an enterprise risk analysis. The understanding of explosions underwent a substantial evolution in the final 20 years of the 20{sup th} century following international research projects in Europe involving several research institutes, as well gas and oil companies. This led to the development of techniques that could be used to assess the potential consequences of explosions on oil, gas and petrochemical facilities. This paper presents an overview of the potential for explosions in communities close to industrial sites or pipelines right of way (RoW), where the standard explosion assessment methods cannot be applied. With reference to experimental studies, the potential for confined explosions in buildings and Vapor Cloud Explosions is explored. Vapor Cloud Explosion incidents in rural or urban areas are also discussed. The method used for incorporating possible explosion and fire events in risk studies is also described using a case study. Standard explosion assessment methodologies and a revised approach are compared as part of an on going evaluation of risk (author)

  1. Fire and explosion hazards to flora and fauna from explosives.

    Science.gov (United States)

    Merrifield, R

    2000-06-30

    Deliberate or accidental initiation of explosives can produce a range of potentially damaging fire and explosion effects. Quantification of the consequences of such effects upon the surroundings, particularly on people and structures, has always been of paramount importance. Information on the effects on flora and fauna, however, is limited, with probably the weakest area lying with fragmentation of buildings and their effects on different small mammals. Information has been used here to gain an appreciation of the likely magnitude of the potential fire and explosion effects on flora and fauna. This is based on a number of broad assumptions and a variety of data sources including World War II bomb damage, experiments performed with animals 30-40 years ago, and more recent field trials on building break-up under explosive loading.

  2. Explosive compositions

    Energy Technology Data Exchange (ETDEWEB)

    1971-04-01

    An explosive composition containing ammonium nitrate consists of (1) from 40 to 75 Pt. by wt of particulate ammonium nitrate, (2) from 20 to 35 Pt. by wt of a solution selected from the group consisting of aqueous magnesium nitrate, aqueous ammonium nitrate and aqueous ammoniacal ammonium nitrate; and (3) at least 2 Pt. by wt of a setting agent selected from the group consisting of alkaline earth metal oxides, zinc oxide, lead monoxide, calcined dolomitic limestone, anhydrous calcium sulfate, anhydrous magnesium sulfate, anhydrous sodium tetrapyrophosphate and anhydrous sodium thiosulfate. The setting agent is further characterized in setting the composition to a solid material which contains solvent used in the liquid phase. (Abstract only - original article not available from T.U.)

  3. Explosive composition

    Energy Technology Data Exchange (ETDEWEB)

    Slykhouse, T E

    1968-05-09

    An ammonium nitrate explosive composition is characterized in that it contains from 40 to 75 parts by wt of particulate ammonium nitrate, from 20 to 35 parts by wt of a solution selected from the group consisting of aqueous magnesium nitrate, aqueous ammonium nitrate, and aqueous ammoniacal ammonium nitrate. It also contains at least 2 parts by wt of a setting agent selected from the group consisting of alkaline earth metal oxides, zinc oxide, lead monoxide, calcined dolomitic limestone, substantially anhydrous calcium sulfate, substantially anhydrous magnesium sulfate, substantially anhydrous sodium tetrapyrophosphate and substantially anhydrous sodium thiosulfate. The setting agent is further characterized in that it sets the composition to a solid material which contains solvent used in the liquid phase. (12 claims)

  4. Slurry explosives

    Energy Technology Data Exchange (ETDEWEB)

    1973-08-23

    A slurry explosive is comprised of (1) a composition consisting of ammonium nitrate or a mixture of ammonium nitrate and an alkali metal nitrate; or an alkaline earth metal nitrate; or an alkali metal nitrate and an alkaline earth metal nitrate; at least one member selected from the group consisting of 2,4,6-trinitrotoluene, aluminum, smokeless powder and fuels; and water; (2) 0.1 to 2.0% of guar gum; (3) between 0% and 0.3% of a sodium, potassium, calcium or magnesium borate; and greater than 0% but not more than 20% of hexamethylene tetramine; and (4) 0.02 to 2.0% of antimony potassium tartarate, antimony trioxide, antimony trisulfide or a mixture of these antimony compounds, % by wt.

  5. Explosive Breakup of a Water Droplet with a Nontransparent Solid Inclusion Heated in a High-Temperature Gaseous Medium

    Directory of Open Access Journals (Sweden)

    Dmitrienko Margarita A.

    2015-01-01

    Full Text Available This paper investigates the evaporation of a water droplet with a comparably sized solid nontransparent inclusion in a high-temperature (500–800 K gas medium. Water evaporates from the free surface of the inclusion. During this process, intensive vapor formation occurs on the inner interface “water droplet – solid inclusion” with the subsequent explosive decay of the droplet. Experiments have been conducted using high-speed (up to 105 fps video cameras “Phantom” and software “Phantom Camera Control”. The conditions of the explosive vapor formation of the heterogeneous water droplet were found. The typical phase change mechanisms of the heterogeneous water droplet under the conditions of intensive heat exchange were determined.

  6. Excavation research with chemical explosives

    International Nuclear Information System (INIS)

    Vandenberg, William E.; Day, Walter C.

    1970-01-01

    The US Army Engineer Nuclear Cratering Group (NCG) is located at the Lawrence Radiation Laboratory in Livermore, California. NCG was established in 1962 and assigned responsibility for technical program direction of the Corps of Engineers Nuclear Excavation Research Program. The major part of the experimental program has been the execution of chemical explosive excavation experiments. In the past these experiments were preliminary to planned nuclear excavation experiments. The experience gained and technology developed in accomplishing these experiments has led to an expansion of NCG's research mission. The overall research and development mission now includes the development of chemical explosive excavation technology to enable the Corps of Engineers to more economically accomplish Civil Works Construction projects of intermediate size. The current and future chemical explosive excavation experiments conducted by NCG will be planned so as to provide data that can be used in the development of both chemical and nuclear excavation technology. In addition, whenever possible, the experiments will be conducted at the specific sites of authorized Civil Works Construction Projects and will be designed to provide a useful portion of the engineering structures planned in that project. Currently, the emphasis in the chemical explosive excavation program is on the development of design techniques for producing specific crater geometries in a variety of media. Preliminary results of two such experiments are described in this paper; Project Pre-GONDOLA III, Phase III, Reservoir Connection Experiment; and a Safety Calibration Series for Project TUGBOAT, a small boat harbor excavation experiment

  7. Excavation research with chemical explosives

    Energy Technology Data Exchange (ETDEWEB)

    Vandenberg, William E; Day, Walter C [U.S. Army Engineer Nuclear Cratering Group, Lawrence Radiation Laboratory, Livermore, CA (United States)

    1970-05-01

    The US Army Engineer Nuclear Cratering Group (NCG) is located at the Lawrence Radiation Laboratory in Livermore, California. NCG was established in 1962 and assigned responsibility for technical program direction of the Corps of Engineers Nuclear Excavation Research Program. The major part of the experimental program has been the execution of chemical explosive excavation experiments. In the past these experiments were preliminary to planned nuclear excavation experiments. The experience gained and technology developed in accomplishing these experiments has led to an expansion of NCG's research mission. The overall research and development mission now includes the development of chemical explosive excavation technology to enable the Corps of Engineers to more economically accomplish Civil Works Construction projects of intermediate size. The current and future chemical explosive excavation experiments conducted by NCG will be planned so as to provide data that can be used in the development of both chemical and nuclear excavation technology. In addition, whenever possible, the experiments will be conducted at the specific sites of authorized Civil Works Construction Projects and will be designed to provide a useful portion of the engineering structures planned in that project. Currently, the emphasis in the chemical explosive excavation program is on the development of design techniques for producing specific crater geometries in a variety of media. Preliminary results of two such experiments are described in this paper; Project Pre-GONDOLA III, Phase III, Reservoir Connection Experiment; and a Safety Calibration Series for Project TUGBOAT, a small boat harbor excavation experiment.

  8. Simulation of Local Seismic Ground Motions from the FLASK Underground Nuclear Explosion near the Source Physics Experiment Dry Alluvium Geology Site

    Science.gov (United States)

    Rodgers, A. J.; Pitarka, A.; Wagoner, J. L.; Helmberger, D. V.

    2017-12-01

    The FLASK underground nuclear explosion (UNE) was conducted in Area 2 of Yucca Flat at the Nevada Test Site on May 26, 1970. The yield was 105 kilotons (DOE/NV-209-Rev 16) and the working point was 529 m below the surface. This test was detonated in faulted Tertiary volcanic rocks of Yucca Flat. Coincidently, the FLASK UNE ground zero (GZ) is close (earth structure, including surface topography. SW4 includes vertical mesh refinement which greatly reduces the computational resources needed to run a specific problem. Simulations are performed on high-performance computers with grid spacing as small as 10 meters and resolution to 6 Hz. We are testing various subsurface models to identify the role of 3D structure on path propagation effects from the source. We are also testing 3D models to constrain structure for the upcoming DAG experiments in 2018.

  9. 78 FR 64246 - Commerce in Explosives; List of Explosives Materials

    Science.gov (United States)

    2013-10-28

    ..., including non-cap sensitive slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting.... Explosive conitrates. Explosive gelatins. Explosive liquids. Explosive mixtures containing oxygen-releasing... powder. [[Page 64247

  10. Hydrocarbon production with nuclear explosives

    International Nuclear Information System (INIS)

    Wade Watkins, J.

    1970-01-01

    The tremendous energy of nuclear explosives and the small dimensions of the explosive package make an ideal combination for drill-hole explosive emplacement in deep, thick hydrocarbon deposits. Potential applications exist in fracturing low permeability natural-gas and petroleum formations for stimulating production, fracturing oil shale to permit in situ retorting, and creating storage chimneys for natural gas, liquefied petroleum gas, petroleum, petroleum products, helium, and other fluids. Calculations show, for example, that less than 100 shots per year would be needed to stabilize the natural gas reserves to production ratio. Under the Government-industry Plowshare program, two experiments, Projects Gasbuggy and Rulison, were conducted to stimulate natural gas production from low-permeability formations. Incomplete information indicates that both were technically successful. Potential problems associated with the use of nuclear explosives for underground engineering applications are radioactive contamination, maximum yield limitations, high costs of detonating contained nuclear explosives, and adverse public opinion. Results at Project Gasbuggy and other considerations indicated that the problem of radioactive contamination was about as predicted and not an insurmountable one. Also, it was demonstrated that shots at adequate depths could be detonated without appreciable damage to existing surface and subsurface buildings, natural features, and equipment. However, costs must be reduced and the public must be better informed before these techniques can be widely used in field operations. On the basis of present knowledge, the potential of nuclear-explosive stimulation of hydrocarbon production appears good. Additional field experiments will be required to adequately explore that potential. (author)

  11. Hydrocarbon production with nuclear explosives

    Energy Technology Data Exchange (ETDEWEB)

    Wade Watkins, J [Petroleum Research, Bureau of Mines, U.S. Department of the Interior, Washington, DC (United States)

    1970-05-01

    The tremendous energy of nuclear explosives and the small dimensions of the explosive package make an ideal combination for drill-hole explosive emplacement in deep, thick hydrocarbon deposits. Potential applications exist in fracturing low permeability natural-gas and petroleum formations for stimulating production, fracturing oil shale to permit in situ retorting, and creating storage chimneys for natural gas, liquefied petroleum gas, petroleum, petroleum products, helium, and other fluids. Calculations show, for example, that less than 100 shots per year would be needed to stabilize the natural gas reserves to production ratio. Under the Government-industry Plowshare program, two experiments, Projects Gasbuggy and Rulison, were conducted to stimulate natural gas production from low-permeability formations. Incomplete information indicates that both were technically successful. Potential problems associated with the use of nuclear explosives for underground engineering applications are radioactive contamination, maximum yield limitations, high costs of detonating contained nuclear explosives, and adverse public opinion. Results at Project Gasbuggy and other considerations indicated that the problem of radioactive contamination was about as predicted and not an insurmountable one. Also, it was demonstrated that shots at adequate depths could be detonated without appreciable damage to existing surface and subsurface buildings, natural features, and equipment. However, costs must be reduced and the public must be better informed before these techniques can be widely used in field operations. On the basis of present knowledge, the potential of nuclear-explosive stimulation of hydrocarbon production appears good. Additional field experiments will be required to adequately explore that potential. (author)

  12. Explosion of a road tanker containing liquefied natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Planas-Cuchi, E.; Casal, J. [Universitat Politecnica de Catalunya, Catalonia (Spain). CERTEC; Gasulla, N.; Ventosa, A. [Autonomous Government of Catalonia (Spain). General Directorate for Emergencies and Civl Security

    2004-07-01

    The explosion of a road tanker transporting LNG (one person killed, two injured) is studied. The analysis shows that the explosion, which followed a two-step mode as for the failure of the vessel, could have been a boiling liquid expanding vapor explosion (BLEVE). The overpressure and thermal radiation have been estimated and related to the effects observed. Only a relatively small part of the energy released in the explosion was manifested in the pressure wave. The large fragments (the three pieces into which the tank was broken) and the truck motor were ejected at various distances along the tank's main axis. (author)

  13. Trend of explosion disasters and direction of disaster prevention. Bakuhatsu saigai no keiko to bosai taisaku no hoko

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, K. (Fir Research Inst., Tokyo (Japan))

    1990-09-01

    Occurence probability and the size of the industrial accident (frequency and intensity) in Japan surpassed USA since 1970, having improved its safety record year by year. The decrease in the occurence of accidents in Japan is a result of various successful measures taken in various sectors of industries. Development of disasters prevention technology is always demanded in accordance with the progress of the science and technology. A methodology of disaster prevention measures comprises accident analysis (statistical or individual)(inductive or passive) and a safety principle (assessment of danger characteristics of the chemical substances, equipment examination technique, risk analysis, analysis of a near-mistake)(deduction or positive), block should support each other for establishing the safety technology. Types of the explosion accident involves a vapor mass explosion, BLEVE (Boiling Liquid Expanding Vapor Explosion), boil-over and vapor explosion, explosion due to run-away reaction, explosion of explosive substance and dust explosion. 13 refs., 6 figs., 2 tabs.

  14. Supernova explosions

    CERN Document Server

    Branch, David

    2017-01-01

    Targeting advanced students of astronomy and physics, as well as astronomers and physicists contemplating research on supernovae or related fields, David Branch and J. Craig Wheeler offer a modern account of the nature, causes and consequences of supernovae, as well as of issues that remain to be resolved. Owing especially to (1) the appearance of supernova 1987A in the nearby Large Magellanic Cloud, (2) the spectacularly successful use of supernovae as distance indicators for cosmology, (3) the association of some supernovae with the enigmatic cosmic gamma-ray bursts, and (4) the discovery of a class of superluminous supernovae, the pace of supernova research has been increasing sharply. This monograph serves as a broad survey of modern supernova research and a guide to the current literature. The book’s emphasis is on the explosive phases of supernovae. Part 1 is devoted to a survey of the kinds of observations that inform us about supernovae, some basic interpreta tions of such data, and an overview of t...

  15. Seismic coupling of nuclear explosions

    International Nuclear Information System (INIS)

    Larson, D.B.

    1989-01-01

    The new Giant Magnet Experimental Facility employing digital recording of explosion induced motion has been constructed and successfully tested. Particle velocity and piezoresistance gage responses can be measured simultaneously thus providing the capability for determining the multi-component stress-strain history in the test material. This capability provides the information necessary for validation of computer models used in simulation of nuclear underground testing, chemical explosion testing, dynamic structural response, earth penetration response, and etc. This report discusses fully coupled and cavity decoupled explosions of the same energy (0.622 kJ) were carried out as experiments to study wave propagation and attenuation in polymethylmethacrylate (PMMA). These experiments produced particle velocity time histories at strains from 2 x 10 -3 to as low as 5.8 x 10 -6 . Other experiments in PMMA, reported recently by Stout and Larson 8 provide additional particle velocity data to strains of 10 -1

  16. Workshop on explosions, BLEVEs, fires, etc.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The purpose of this workshop will be to provide a bridge between engineering practices, modeling, and measurement of fires and explosions, and use this information in a practical manner to improve the fire safety of the process facility. New techniques and information are available on the means to prevent, predict and mitigate fires and explosions. A review of BLEVEs and methods for preventing and protecting against the effects of BLEVES in large petrochemical facilities. Observations and the use of models that have been successful in predicting the effects of vapor explosions for the prevention of collapse of structures and mitigation of the effects of vapor explosions in process facilities are presented. Recent work involving the measurement of radiation from large jet fires at the Kuwaiti oil fields and fire tests of crude oil spills on the sea is discussed. Fire radiation measurement can be used to predict effects on structures, facilities, and the complexity of fire fighting operations required for control of spill and pool fires. Practical applications of techniques for prevention and control of explosions within building, resulting from failures of autoclaves or release of flammable gas to the atmosphere of the building are discussed.

  17. Vapor liquid fraction determination

    International Nuclear Information System (INIS)

    1980-01-01

    This invention describes a method of measuring liquid and vapor fractions in a non-homogeneous fluid flowing through an elongate conduit, such as may be required with boiling water, non-boiling turbulent flows, fluidized bed experiments, water-gas mixing analysis, and nuclear plant cooling. (UK)

  18. Modelling of vapour explosion in stratified geometrie

    International Nuclear Information System (INIS)

    Picchi, St.

    1999-01-01

    When a hot liquid comes into contact with a colder volatile liquid, one can obtain in some conditions an explosive vaporization, told vapour explosion, whose consequences can be important on neighbouring structures. This explosion needs the intimate mixing and the fine fragmentation between the two liquids. In a stratified vapour explosion, these two liquids are initially superposed and separated by a vapor film. A triggering of the explosion can induce a propagation of this along the film. A study of experimental results and existent models has allowed to retain the following main points: - the explosion propagation is due to a pressure wave propagating through the medium; - the mixing is due to the development of Kelvin-Helmholtz instabilities induced by the shear velocity between the two liquids behind the pressure wave. The presence of the vapour in the volatile liquid explains experimental propagation velocity and the velocity difference between the two fluids at the pressure wave crossing. A first model has been proposed by Brayer in 1994 in order to describe the fragmentation and the mixing of the two fluids. Results of the author do not show explosion propagation. We have therefore built a new mixing-fragmentation model based on the atomization phenomenon that develops itself during the pressure wave crossing. We have also taken into account the transient aspect of the heat transfer between fuel drops and the volatile liquid, and elaborated a model of transient heat transfer. These two models have been introduced in a multi-components, thermal, hydraulic code, MC3D. Results of calculation show a qualitative and quantitative agreement with experimental results and confirm basic options of the model. (author)

  19. Understanding vented gas explosions

    Energy Technology Data Exchange (ETDEWEB)

    Lautkaski, R. [VTT Energy, Espoo (Finland). Energy Systems

    1997-12-31

    The report is an introduction to vented gas explosions for nonspecialists, particularly designers of plants for flammable gases and liquids. The phenomena leading to pressure generation in vented gas explosions in empty and congested rooms are reviewed. The four peak model of vented gas explosions is presented with simple methods to predict the values of the individual peaks. Experimental data on the external explosion of dust and gas explosions is discussed. The empirical equation relating the internal and external peak pressures in vented dust explosions is shown to be valid for gas explosion tests in 30 m{sup 3} and 550 m{sup 3} chambers. However, the difficulty of predicting the internal peak pressure in large chambers remains. Methods of explosion relief panel design and principles of vent and equipment layout to reduce explosion overpressures are reviewed. (orig.) 65 refs.

  20. Understanding vented gas explosions

    Energy Technology Data Exchange (ETDEWEB)

    Lautkaski, R [VTT Energy, Espoo (Finland). Energy Systems

    1998-12-31

    The report is an introduction to vented gas explosions for nonspecialists, particularly designers of plants for flammable gases and liquids. The phenomena leading to pressure generation in vented gas explosions in empty and congested rooms are reviewed. The four peak model of vented gas explosions is presented with simple methods to predict the values of the individual peaks. Experimental data on the external explosion of dust and gas explosions is discussed. The empirical equation relating the internal and external peak pressures in vented dust explosions is shown to be valid for gas explosion tests in 30 m{sup 3} and 550 m{sup 3} chambers. However, the difficulty of predicting the internal peak pressure in large chambers remains. Methods of explosion relief panel design and principles of vent and equipment layout to reduce explosion overpressures are reviewed. (orig.) 65 refs.

  1. Tubing For Sampling Hydrazine Vapor

    Science.gov (United States)

    Travis, Josh; Taffe, Patricia S.; Rose-Pehrsson, Susan L.; Wyatt, Jeffrey R.

    1993-01-01

    Report evaluates flexible tubing used for transporting such hypergolic vapors as those of hydrazines for quantitative analysis. Describes experiments in which variety of tubing materials, chosen for their known compatibility with hydrazine, flexibility, and resistance to heat.

  2. Hanford soil partitioning and vapor extraction study

    International Nuclear Information System (INIS)

    Yonge, D.; Hossain, A.; Cameron, R.; Ford, H.; Storey, C.

    1996-07-01

    This report describes the testing and results of laboratory experiments conducted to assist the carbon tetrachloride soil vapor extraction project operating in the 200 West Area of the Hanford Site in Richland, Washington. Vapor-phase adsorption and desorption testing was performed using carbon tetrachloride and Hanford Site soils to estimate vapor-soil partitioning and reasonably achievable carbon tetrachloride soil concentrations during active vapor extractions efforts at the 200 West Area. (CCl 4 is used in Pu recovery from aqueous streams.)

  3. Experiments in progress: The geography of science in the Atomic Energy Commission's peaceful uses of nuclear explosives program, 1956-1973

    Science.gov (United States)

    Kirsch, Scott Lawrence

    From 1957 to 1973, the United States Atomic Energy Commission (AEC) actively pursued the "peaceful uses of nuclear explosives" through Project Plowshare. Nuclear excavation, the detonation of shallowly buried hydrogen bombs for massive earthmoving projects like harbors and canals, was considered the most promising of the Plowshare applications, and for a time, the most economically and technically "feasible." With a basis in and contributing to theory in critical human geography and science studies, the purpose of this dissertation is to examine the collisions of science, ideology, and politics which kept Plowshare designs alive--but only as "experiments in progress." That is, this research asks how the experimental program persisted in places like the national weapons laboratory in Livermore, California, and how its ideas were tested at the nuclear test site in Nevada, yet Plowshare was kept out of those spaces beyond AEC control. Primary research focuses on AEC-related archival materials collected from the Department of Energy Coordination and Information Center, Las Vegas, Nevada, and from the Lawrence Livermore National Laboratory, as well as the public discourse through which support for and opposition to Plowshare projects was voiced. Through critical analysis of Plowshare's grandiose "geographical engineering" schemes, I thus examine the complex relations between the social construction of science and technology, on one hand, and the social production of space, on the other.

  4. 25 years of experience with closed cycle vapor turbogenerators as primary power source in remote telecommunications projects in Russia and CIS countries

    Energy Technology Data Exchange (ETDEWEB)

    Gropper, J. [ORMAT Industries Ltd., Yavne (Israel)

    2000-07-01

    One of the most severe problems confronting telecommunications projects in extreme arctic environment conditions, with temperatures as low as -60 C, is the supply of continuous, reliable remote power for unattended microwave repeater stations that in many cases cannot be reached by maintenance technicians for months at a time. Another important problem is that the telecommunications equipment must be kept at temperatures between 0 C and +45 C in order to ensure correct electronics operation. The obvious, simple solution of having an electrical heater in the equipment shelter is not practical because of the power required for such a heater. The use of specially designed, arctic type, closed cycle vapor turbogenerators (CCVT) and their associated non-electric heating systems in arctic telecommunication systems has solved both problems: reliable remote power in the range of 400 to 2500 Watts in provided with maintenance requirements reduced to a visit only once in 6 months or more, and required temperature ranges in equipment shelters are maintained, assuring correct operation of the sensitive electronics, without any need of electrical power. During the last 25 years, many major telecommunication projects in Siberia, Alaska and Antarctica have been designed to use and continue to use over 1200 arctic type closed cycle vapor turbogenerators. The CCVTs are designed to operate at nominal power in a range of temperatures from -60 to +45 C and at wind velocity of 120 km/hr, with acceptable gusts of 160 km/hr. They can be fuelled by either arctic kerosene or diesel fuel, or by natural or liquefied gas (LPG) and provide 24 or 48 VDC to the telecommunications equipment. The non-electric heating system associated with the CCVT draws extra heat accumulated in the CCVT's vapor turbogenerator in winter to vaporize a fluid that will transmit 1000 kcal/hr of heat to the equipment shelter or room where telecommunication equipment is located. The heating system is

  5. Vapor Pressure Plus: An Experiment for Studying Phase Equilibria in Water, with Observation of Supercooling, Spontaneous Freezing, and the Triple Point

    Science.gov (United States)

    Tellinghuisen, Joel

    2010-01-01

    Liquid-vapor, solid-vapor, and solid-liquid-vapor equilibria are studied for the pure substance water, using modern equipment that includes specially fabricated glass cells. Samples are evaporatively frozen initially, during which they typically supercool to -5 to -10 [degrees]C before spontaneously freezing. Vacuum pumping lowers the temperature…

  6. Inhomogeneous wire explosion in water

    International Nuclear Information System (INIS)

    Hwangbo, C.K.; Kong, H.J.; Lee, S.S.

    1980-01-01

    Inhomogeneous processes are observed in underwater copper wire explosion induced by a condensed capacitor discharge. The wire used is 0.1 mm in diameter and 10 mm long, and the capacitor of 2 μF is charged to 5 KV. A N 2 laser is used for the diagnostic of spatial extension of exploding copper vapour. The photographs obtained in this experiment show unambiguously the inhomogeneous explosion along the exploding wire. The quenching of plasma by the surrounding water inhibits the expansion of the vapour. It is believed the observed inhomogeneous explosion along the wire is located and localized around Goronkin's striae, which was first reported by Goronkin and discussed by Froengel as a pre-breakdown phenomenon. (author)

  7. Premixing and steam explosion phenomena in the tests with stratified melt-coolant configuration and binary oxidic melt simulant materials

    Energy Technology Data Exchange (ETDEWEB)

    Kudinov, Pavel, E-mail: pavel@safety.sci.kth.se; Grishchenko, Dmitry, E-mail: dmitry@safety.sci.kth.se; Konovalenko, Alexander, E-mail: kono@kth.se; Karbojian, Aram, E-mail: karbojan@kth.se

    2017-04-01

    Highlights: • Steam explosion in stratified melt-coolant configuration is studied experimentally. • Different binary oxidic melt simulant materials were used. • Five spontaneous steam explosions were observed. • Instability of melt-coolant interface and formation of premixing layer was observed. • Explosion strength is influenced by melt superheat and water subcooling. - Abstract: Steam explosion phenomena in stratified melt-coolant configuration are considered in this paper. Liquid corium layer covered by water on top can be formed in severe accident scenarios with (i) vessel failure and release of corium melt into a relatively shallow water pool; (ii) with top flooding of corium melt layer. In previous assessments of potential energetics in stratified melt-coolant configuration, it was assumed that melt and coolant are separated by a stable vapor film and there is no premixing prior to the shock wave propagation. This assumption was instrumental for concluding that the amount of energy that can be released in such configuration is not of safety importance. However, several recent experiments carried out in Pouring and Under-water Liquid Melt Spreading (PULiMS) facility with up to 78 kg of binary oxidic corium simulants mixtures have resulted in spontaneous explosions with relatively high conversion ratios (order of one percent). The instability of the melt-coolant interface, melt splashes and formation of premixing layer were observed in the tests. In this work, we present results of experiments carried out more recently in steam explosion in stratified melt-coolant configuration (SES) facility in order to shed some light on the premixing phenomena and assess the influence of the test conditions on the steam explosion energetics.

  8. Vapour cloud explosion hazard greater with light feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Windebank, C.S.

    1980-03-03

    Because lighter chemical feedstocks such as propylene and butylenes are more reactive than LPG's they pose a greater risk of vapor cloud explosion, particularly during their transport. According to C.S. Windebank (Insurance Tech. Bur.), percussive unconfined vapor cloud explosions (PUVCE's) do not usually occur below the ten-ton threshold for saturated hydrocarbons but can occur well below this threshold in the case of unsaturated hydrocarbons such as propylene and butylenes. Boiling liquid expanding vapor explosions (BLEVE's) are more likely to be ''hot'' (i.e., the original explosion is associated with fire) than ''cold'' in the case of unsaturated hydrocarbons. No PUVCE or BLEVE incident has been reported in the UK. In the US, 16 out of 20 incidents recorded between 1970 and 1975 were related to chemical feedstocks, including propylene and butylenes, and only 4 were LPG-related. The average losses were $20 million per explosion. Between 1968 and 1978, 8% of LPG pipeline spillages led to explosions.

  9. The fracture of concrete under explosive shock loading

    International Nuclear Information System (INIS)

    Watson, A.J.; Sanderson, A.J.

    1982-01-01

    Concrete fracture close to the point of application of high explosive shock pressures has been studied experimentally by placing an explosive charge on the edge of a concrete slab. The extent of the crushing and cracking produced by a semi cylindrical diverging plane compressive stress pulse has been measured and complementary experiments gave the pressure transmitted at an explosive to concrete interface and the stress-strain relation for concrete at explosive strain rates. (orig.) [de

  10. Mobile vapor recovery and vapor scavenging unit

    International Nuclear Information System (INIS)

    Stokes, C.A.; Steppe, D.E.

    1991-01-01

    This patent describes a mobile anti- pollution apparatus, for the recovery of hydrocarbon emissions. It comprises a mobile platform upon which is mounted a vapor recovery unit for recovering vapors including light hydrocarbons, the vapor recovery unit having an inlet and an outlet end, the inlet end adapted for coupling to an external source of hydrocarbon vapor emissions to recover a portion of the vapors including light hydrocarbons emitted therefrom, and the outlet end adapted for connection to a means for conveying unrecovered vapors to a vapor scavenging unit, the vapor scavenging unit comprising an internal combustion engine adapted for utilizing light hydrocarbon in the unrecovered vapors exiting from the vapor recovery unit as supplemental fuel

  11. Microscale interfacial behavior at vapor film collapse on high-temperature particle surface

    International Nuclear Information System (INIS)

    Abe, Yutaka; Tochio, Daisuke

    2009-01-01

    It has been pointed out that vapor film on a premixed high-temperature droplet surface should be collapsed to trigger vapor explosion. Thus, it is important to clarify the micromechanism of vapor film collapse behavior for the occurrence of vapor explosion. In the present study, microscale vapor-liquid interface behavior upon vapor film collapse caused by an external pressure pulse is experimentally observed and qualitatively analyzed. In the analytical investigation, interfacial temperature and interface movement were estimated with heat conduction analysis and visual data processing technique. Results show that condensation can possibly occur at the vapor-liquid interface when the pressure pulse arrived. That is, this result indicates that the vapor film collapse behavior is dominated not by fluid motion but by phase change. (author)

  12. Vaporization of mercury from molten lead droplets doped with mercury: Pb/Hg source term experiment for the APT/SILC target

    International Nuclear Information System (INIS)

    Tutu, N.K.; Greene, G.A.

    1994-09-01

    Experiments were performed to measure the fraction of mercury inventory released when droplets of molten lead, doped with a known concentration of mercury, fall through a controlled environment. The temperature of molten droplets ranged from 335 C to 346 C, and the concentration of mercury in the droplets ranged from 0.2 mass % to 1.0 mass %. The environment consisted of an air stream, at a temperature nominally equal to the melt temperature, and moving vertically upwards at a velocity of 10 cm/s. Direct observations and chemical analysis showed that no mercury was released from the molten droplets. Based upon the experimental results, it is concluded that no mercury vapor is likely to be released from the potentially molten source rod material in the APT-SILC Neutron Source Array to the confinement atmosphere during a postulated Large Break Loss Of Coolant Accident scenario leading to the melting of a fraction of the source rods

  13. Underground nuclear explosions. Study of the cavity radius

    International Nuclear Information System (INIS)

    Michaud, L.

    1968-11-01

    An underground nuclear explosion creates a cavity due to the expansion of the surrounding medium vaporized by the shot. The cavity radius is related to the energy of explosion and to the overburden pressure of the medium. The introduction of new elements such as the environment of the device (in a deep hole or in a tunnel) and the cohesion of the medium leads to a relationship which determines this radius. The known French and American underground explosions performed in various media, energy and overburden conditions, satisfy this relationship with a good precision. (author) [fr

  14. Explosive fragmentation

    Science.gov (United States)

    Vledouts, Alexandre; Graña-Otero, José; Quinard, Joel; Vandenberghe, Nicolas; Villermaux, Emmanuel

    2013-11-01

    We report on an experiment consisting in forcing the fast radial expansion of a spherical liquid shell. The shell is formed by the capillary pinch off of a water thin annular jet surrounding a jet of reactive gaseous mixture at ambient pressure. The encapsulated gas in the resulting water bubble is a mixture of Hydrogen and Oxygen in controlled relative proportions, which is ignited by a laser plasma aimed at the center of the bubble. The strongly exothermic combustion of the mixture induces the expansion of the hot burnt gas, pushing the shell radially outwards in a violently accelerated motion. That motion triggers the instability of the shell, developing thickness modulations ultimately piercing it in a number of holes. The capillary retraction of the holes concentrates the liquid constitutive of the shell into a web of ligaments, whose breakup leads to stable drops. We document the overall process, from the kinematics of the shell initial expansion, to the final drops size distribution as a function of the composition of the gas mixture and bubble shell thickness.

  15. Steam explosion simulation code JASMINE v.3 user's guide

    International Nuclear Information System (INIS)

    Moriyama, Kiyofumi; Maruyama, Yu; Nakamura, Hideo

    2008-07-01

    A steam explosion occurs when hot liquid contacts with cold volatile liquid. In this phenomenon, fine fragmentation of the hot liquid causes extremely rapid heat transfer from the hot liquid to the cold volatile liquid, and explosive vaporization, bringing shock waves and destructive forces. The steam explosion due to the contact of the molten core material and coolant water during severe accidents of light water reactors has been regarded as a potential threat to the integrity of the containment vessel. We developed a mechanistic steam explosion simulation code, JASMINE, that is applicable to plant scale assessment of the steam explosion loads. This document, as a manual for users of JASMINE code, describes the models, numerical solution methods, and also some verification and example calculations, as well as practical instructions for input preparation and usage of the code. (author)

  16. Close-in airblast from underground explosions

    Energy Technology Data Exchange (ETDEWEB)

    Vortman, L J [Sandia Laboratories, Albuquerque, NM (United States)

    1970-05-15

    Air overpressures as a function of time have been measured from surface zero to about 170 ft/lb{sup 1/3} along the ground from nuclear and chemical explosions. Charge depths varied from the surface to depths below which explosion gases are contained. A ground-shock-induced air pressure pulse is clearly distinguishable from the pulse caused by venting gases. Measured peak overpressures show reasonable agreement with the theoretical treatment by Monta. In a given medium the suppression of blast with explosion burial depth is a function of the relative distance at which the blast is observed. Rates of suppression of peak overpressure with charge burial are different for the two pulses. Rates are determined for each pulse over the range of distances at which measurements have been made of air overpressure from chemical explosions in several media. Nuclear data are available from too few shots for similar dependence on burial depth and distance to be developed, but it is clear that the gas venting peak overpressure from nuclear explosions is much more dependent on medium than that from chemical explosions. For above-ground explosions, experiment has shown that airblast from a I-kiloton nuclear explosion is equal to that from a 0.5-kiloton TNT explosion. Data on ground-shock-induced airblast is now sufficient to show that a similar relationship may exist for buried explosions. Because of medium dependence of the gas venting pulse from nuclear explosions, data from additional nuclear events will be required before a chemical/nuclear airblast equivalence can be determined for the gas-venting pulse. (author)

  17. Ground Based Experiments in Support of Microgravity Research Results-Vapor Growth of Organic Nonlinear Optical Thin Film

    Science.gov (United States)

    Zugrav, M. Ittu; Carswell, William E.; Haulenbeek, Glen B.; Wessling, Francis C.

    2001-01-01

    This work is specifically focused on explaining previous results obtained for the crystal growth of an organic material in a reduced gravity environment. On STS-59, in April 1994, two experiments were conducted with N,N-dimethyl-p-(2,2-dicyanovinyl) aniline (DCVA), a promising nonlinear optical (NLO) material. The space experiments were set to reproduce laboratory experiments that yielded small, bulk crystals of DCVA. The results of the flight experiment, however, were surprising. Rather than producing a bulk single crystal, the result was the production of two high quality, single crystalline thin films. This result was even more intriguing when it is considered that thin films are more desirable for NLO applications than are bulk single crystals. Repeated attempts on the ground to reproduce these results were fruitless. A second set of flight experiments was conducted on STS-69 in September 1995. This time eight DCVA experiments were flown, with each of seven experiments containing a slight change from the first reference experiment. The reference experiment was programmed with growth conditions identical to those of the STS-59 mission. The slight variations in each of the other seven were an attempt to understand what particular parameter was responsible for the preference of thin film growth over bulk crystal growth in microgravity. Once again the results were surprising. In all eight cases thin films were grown again, albeit with varying quality. So now we were faced with a phenomenon that not only takes place in microgravity, but also is very robust, resisting all attempts to force the growth of bulk single crystals.

  18. Impulsive shock induced single drop steam explosion visualized by high-speed x-ray radiography and photography - metallic melt

    International Nuclear Information System (INIS)

    Park, H. S.; Hansson, R. C.; Sehgal, B. R.

    2003-01-01

    Experimental investigation of fine fragmentation process during vapor explosion was conducted in a small-scale single drop system employing continuous high-speed X-ray radiography and photography. A molten tin drop of about 0.7 g at approximately 1000 .deg. C was dropped into a water pool, at temperatures ranging from 20 to 90 .deg. C, and the explosion was triggered by an external shock pulse of about 1 MPa. X-ray radiographs show that finely fragmented melt particles accelerates to the vapor bubble boundary and forms a particle shell during the period of vapor bubble expansion due to vapor explosions. From the photographs, it was possible to observe a number of counter-jets on the vapor boundary. For tests with highly subcooled coolant, local explosion due to external impulsive shock trigger initiates the stratified mode of explosion along the entire melt surface. For tests with lower subcooled coolant local explosions were initiated by an external impulsive shock trigger and by collapse of vapor/gas pocket attached on the top of the melt drop. Transient spatial distribution map of melt fragments during vapor explosion was obtained by a series of image processing and calibration tests

  19. Steam-explosion mitigation with polymer and surfactant additives; Mitigation de l`explosion-vapeur par ajout de polymeres et d`agents tensio-actifs

    Energy Technology Data Exchange (ETDEWEB)

    Pineau, D.; Ranval, W.

    1996-02-01

    Vapor explosion (or MFCI for Molten Fuel-Coolant Interaction) is a phenomenon in which a hot liquid rapidly transfers its internal energy into a surrounding colder and more volatile liquid (the coolant) which vaporization is violent. One of the simplest coolant is water. However it was noticed that some particular additives in water could have a mitigative effect on this phenomenon. This paper deals with the description of polymeric and/or surfactant solutions and their ability to suppress vapor explosion. (authors). 24 refs., 5 figs.

  20. New Mix Explosives for Explosive Welding

    Science.gov (United States)

    Andreevskikh, Leonid

    2011-06-01

    Suggested and tested were some mix explosives--powder mixtures of a brisant high explosive (HE = RDX, PETN) and an inert diluent (baking soda)--for use in explosive welding. RDX and PETN were selected in view of their high throwing ability and low critical diameter. Since the decomposition of baking soda yields a huge amount of gaseous products, its presence ensures (even at a low HE percentage) a throwing speed that is sufficient for realization of explosive welding, at a reduced brisant action of charge. Mix chargers containing 30-70 wt % HE (the rest baking soda) have been tested experimentally and optimized. For study of possibility to reduce critical diameter of HE mixture, the mixture was prepared where HE crystal sizes did not exceed 10 μm. The tests, which were performed with this HE, revealed that the mixture detonated stably with the velocity D ~ 2 km/s, if the layer thickness was d = 2 mm. The above explosives afford to markedly diminish deformations within the oblique impact zone and thus to carry out explosive welding of hollow items and thin metallic foils.

  1. Explosion-produced ground motion: technical summary with respect to seismic hazards

    Energy Technology Data Exchange (ETDEWEB)

    Rodean, Howard C [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-15

    This paper summarizes the present technical knowledge, experimental and theoretical, of how underground nuclear explosions produce seismic motion that may be a hazard at distances measured in tens of kilometers. The effects of explosion yield and rock properties (at the explosion, along the signal propagation path, and at the site where a hazard may exist) on the ground motion are described in detail, and some consideration is given to the relation between ground motion and damage criteria. The energy released in a nuclear explosion is sufficient to vaporize the explosive and to generate an intense shock wave that is propagated outward into the surrounding rock. Part of the energy transported by the shock wave is dissipated in the shocked material. The shock wave strength decreases with distance from the center of the explosion as a consequence of this energy loss and because of geometric (approximately spherical) divergence. The dissipated energy fraction ranges from over 95% (for competent rocks like granite) to over 99% (for crushable, porous rocks like alluvium) of the explosion yield. Therefore, the energy fraction that is radiated in the form of seismic waves ranges from a few percent down to a few tenths of a percent. This is consistent with the observation that explosions in granite produce more severe ground motion than corresponding explosions in alluvium. The effects of explosion yield and rock properties on the frequency spectrum of the seismic source function are demonstrated by both experimental measurements and theoretical analysis. The characteristics of an ideal elastic medium are such that its frequency response is that of a low-pass filter, with its cutoff frequency being a function of the elastic properties of the material and the radius at which the explosion-produced stress wave becomes elastic. There is further frequency- and distance-dependent attenuation (especially of the higher frequencies) of the seismic waves, because rocks are not

  2. Explosion-produced ground motion: technical summary with respect to seismic hazards

    International Nuclear Information System (INIS)

    Rodean, Howard C.

    1970-01-01

    This paper summarizes the present technical knowledge, experimental and theoretical, of how underground nuclear explosions produce seismic motion that may be a hazard at distances measured in tens of kilometers. The effects of explosion yield and rock properties (at the explosion, along the signal propagation path, and at the site where a hazard may exist) on the ground motion are described in detail, and some consideration is given to the relation between ground motion and damage criteria. The energy released in a nuclear explosion is sufficient to vaporize the explosive and to generate an intense shock wave that is propagated outward into the surrounding rock. Part of the energy transported by the shock wave is dissipated in the shocked material. The shock wave strength decreases with distance from the center of the explosion as a consequence of this energy loss and because of geometric (approximately spherical) divergence. The dissipated energy fraction ranges from over 95% (for competent rocks like granite) to over 99% (for crushable, porous rocks like alluvium) of the explosion yield. Therefore, the energy fraction that is radiated in the form of seismic waves ranges from a few percent down to a few tenths of a percent. This is consistent with the observation that explosions in granite produce more severe ground motion than corresponding explosions in alluvium. The effects of explosion yield and rock properties on the frequency spectrum of the seismic source function are demonstrated by both experimental measurements and theoretical analysis. The characteristics of an ideal elastic medium are such that its frequency response is that of a low-pass filter, with its cutoff frequency being a function of the elastic properties of the material and the radius at which the explosion-produced stress wave becomes elastic. There is further frequency- and distance-dependent attenuation (especially of the higher frequencies) of the seismic waves, because rocks are not

  3. A Computational Investigation of Various Water-Induced Explosion Mitigation Mechanisms

    Science.gov (United States)

    2007-01-01

    Guidelines for Evaluating the Characteristics of Vapor Cloud Explosions, Flash Fires, and BLEVEs , Center for Chemical Process Safety, AIChE, New York, NY...1994. [6]. Liebman and J. K. Richmond, Suppression of Coal Dust Explosions by Passive Water Barriers in a single Entry Mine , U.S. Bureau of Mines ...R.I. 8294, 1974. [7]. Liebman, J. Corry and J. K. Richmond, Water Barriers for Suppressing Coal Dust Explosions, U.S. Bureau of Mines R.I. 8170

  4. Petroleum Vapor Intrusion

    Science.gov (United States)

    One type of vapor intrusion is PVI, in which vapors from petroleum hydrocarbons such as gasoline, diesel, or jet fuel enter a building. Intrusion of contaminant vapors into indoor spaces is of concern.

  5. Free radical explosive composition

    Science.gov (United States)

    Walker, Franklin E.; Wasley, Richard J.

    1979-01-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a getter additive comprising a compound or mixture of compounds capable of capturing or deactivating free radicals or ions under mechanical or electrical shock conditions and which is not an explosive. Exemplary getter additives are isocyanates, olefins and iodine.

  6. Nuclear explosives and hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, P

    1971-10-01

    A nuclear explosive 12 in. in diam and producing very little tritium is feasible in France. Such a device would be well adapted for contained nuclear explosions set off for the purpose of hydrocarbon storage or stimulation. The different aspects of setting off the explosive are reviewed. In the particular case of gas storage in a nuclear cavity in granite, it is demonstrated that the dose of irradiation received is extremely small. (18 refs.)

  7. Chernobyl explosion bombshell

    International Nuclear Information System (INIS)

    Martin, S.; Arnott, D.

    1988-01-01

    It is suggested that the explosion at the Chernobyl-4 reactor in April 1986 was a nuclear explosion. The evidence for this is examined. The sequence of events at Chernobyl is looked at to see if the effects were like those from a nuclear explosion. The question of whether a United Kingdom reactor could go prompt critical is discussed. It is concluded that prompt criticality excursions are possible, but the specific Chernobyl sequence is impossible. (UK)

  8. Explosive Technology Group

    Data.gov (United States)

    Federal Laboratory Consortium — The Explosive Technology Group (ETG) provides diverse technical expertise and an agile, integrated approach to solve complex challenges for all classes of energetic...

  9. Thermochemistry of mixed explosives

    International Nuclear Information System (INIS)

    Janney, J.L.; Rogers, R.N.

    1982-01-01

    In order to predict thermal hazards of high-energy materials, accurate kinetics constants must be determined. Predictions of thermal hazards for mixtures of high-energy materials require measurements on the mixtures, because interactions among components are common. A differential-scanning calorimeter (DSC) can be used to observe rate processes directly, and isothermal methods enable detection of mechanism changes. Rate-controlling processes will change as components of a mixture are depleted, and the correct depletion function must be identified for each specific stage of a complex process. A method for kinetics measurements on mixed explosives can be demonstrated with Composition B is an approximately 60/40 mixture of RDX and TNT, and is an important military explosive. Kinetics results indicate that the mator process is the decomposition of RDX in solution in TNT with a perturbation caused by interaction between the two components. It is concluded that a combination of chemical kinetics and experimental self-heating procedures provides a good approach to the production of predictive models for thermal hazards of high-energy materials. Systems involving more than one energy-contributing component can be studied. Invalid and dangerous predictive models can be detected by a failure of agreement between prediction and experiment at a specific size, shape, and density. Rates of thermal decomposition for Composition B appear to be modeled adequately for critical-temperature predictions with the following kinetics constants: E = 180.2 kJ mole -1 and Z = 4.62 X 10 16 s -1

  10. Progress in the development of explosives materials detectors

    International Nuclear Information System (INIS)

    Williams, W.D.; Conrad, F.J.; Sandlin, L.L.; Burrows, T.A.

    1978-01-01

    Five hand-held explosives vapor detectors (Elscint Model EXD-2, ITI Model 70, Leigh-Marsland Model S-201, Pye Dynamics Model PD.2.A, and Xonics Model GC-710) were evaluated for sensitivity to a variety of explosives, identification of false alarm agents, and general performance and maintenance characteristics. The results of this evaluation, as presented, indicate that there is no single explosives detector which is best-suited for use at all nuclear facilities. Rather, there are several site-specific elements which must be considered when choosing an explosives detector. There are several new explosives detector technologies being developed which will out-perform existing commercial equipment. Some of these new detectors may be commercially available by the end of fiscal year 1980 and will be cost-effective to purchase and operate. The following areas of explosives detection research are discussed: nitrogen-phosphorous detectors, plasma chromatography, mass spectroscopy, small animal olfactory, vapor preconcentration, nuclear quadrupole resonance, far infrared radiation imaging, nuclear magnetic resonance, thermal neutron activation, and computerized tomography

  11. Explosion metal welding

    International Nuclear Information System (INIS)

    Popoff, A.A.

    1976-01-01

    Process parameters pertaining to welding similar and dissimilar metals using explosives are reviewed. The discussion centers on the interrelationship of physical parameters which play a part in achieving desirable metallurgical results. Present activities in explosion metal welding at LASL are presented and shown how they related to the interests of the ERDA community

  12. Cell phone explosion.

    Science.gov (United States)

    Atreya, Alok; Kanchan, Tanuj; Nepal, Samata; Pandey, Bhuwan Raj

    2016-03-01

    Cell phone explosions and resultant burn injuries are rarely reported in the scientific literature. We report a case of cell phone explosion that occurred when a young male was listening to music while the mobile was plugged in for charging. © The Author(s) 2015.

  13. Underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, Gary H [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-01

    In the Third Plowshare Symposium, held in 1964, data from a number of nuclear explosions were presented. At that time the basic elements of the nuclear explosion appeared to be well understood and relationships for predicting the gross nuclear effects were presented. Since that time, additional work has been done and many of the concepts have been extended. For example, nuclear explosions have been conducted at greater depths and with much greater yields. The physical and chemical properties of the material in which the explosions occur have been more accurately measured and related to explosion effects. Interpretation of the new information seems to indicate that the earlier relationships are valid over the ranges of energy and depths for which data is available but that effects relating to cavity and chimney sizes or fracturing had been overestimated at great depths of burst and higher yields. (author)

  14. Underground nuclear explosions

    International Nuclear Information System (INIS)

    Higgins, Gary H.

    1970-01-01

    In the Third Plowshare Symposium, held in 1964, data from a number of nuclear explosions were presented. At that time the basic elements of the nuclear explosion appeared to be well understood and relationships for predicting the gross nuclear effects were presented. Since that time, additional work has been done and many of the concepts have been extended. For example, nuclear explosions have been conducted at greater depths and with much greater yields. The physical and chemical properties of the material in which the explosions occur have been more accurately measured and related to explosion effects. Interpretation of the new information seems to indicate that the earlier relationships are valid over the ranges of energy and depths for which data is available but that effects relating to cavity and chimney sizes or fracturing had been overestimated at great depths of burst and higher yields. (author)

  15. Research topics in explosives - a look at explosives behaviors

    International Nuclear Information System (INIS)

    Maienschein, J L

    2014-01-01

    The behaviors of explosives under many conditions - e.g., sensitivity to inadvertent reactions, explosion, detonation - are controlled by the chemical and physical properties of the explosive materials. Several properties are considered for a range of improvised and conventional explosives. Here I compare these properties across a wide range of explosives to develop an understanding of explosive behaviors. For improvised explosives, which are generally heterogeneous mixtures of ingredients, a range of studies is identified as needed to more fully understand their behavior and properties. For conventional explosives, which are generally comprised of crystalline explosive molecules held together with a binder, I identify key material properties that determine overall sensitivity, including the extremely safe behavior of Insensitive High Explosives, and discuss an approach to predicting the sensitivity or insensitivity of an explosive.

  16. Time-resolved dynamics of nanosecond laser-induced phase explosion

    International Nuclear Information System (INIS)

    Porneala, Cristian; Willis, David A

    2009-01-01

    Visualization of Nd : YAG laser ablation of aluminium targets was performed by a shadowgraph apparatus capable of imaging the dynamics of ablation with nanosecond time resolution. Direct observations of vaporization, explosive phase change and shock waves were obtained. The influence of vaporization and phase explosion on shock wave velocity was directly measured. A significant increase in the shock wave velocity was observed at the onset of phase explosion. However, the shock wave behaviour followed the form of a Taylor-Sedov spherical shock below and above the explosive phase change threshold. The jump in the shock wave velocity above phase explosion threshold is attributed to the release of stored enthalpy in the superheated liquid surface. The energy released during phase explosion was estimated by fitting the transient shock wave position to the Taylor scaling rules. Results of temperature calculations indicate that the vapour temperature at the phase explosion threshold is slightly higher than the critical temperature at the early stages of the shock wave formation. The shock wave pressure nearly doubled when transitioning from normal vaporization to phase explosion.

  17. Ultrafast laser based coherent control methods for explosives detection

    Energy Technology Data Exchange (ETDEWEB)

    Moore, David Steven [Los Alamos National Laboratory

    2010-12-06

    The detection of explosives is a notoriously difficult problem, especially at stand-off, due to their (generally) low vapor pressure, environmental and matrix interferences, and packaging. We are exploring Optimal Dynamic Detection of Explosives (ODD-Ex), which exploits the best capabilities of recent advances in laser technology and recent discoveries in optimal shaping of laser pulses for control of molecular processes to significantly enhance the standoff detection of explosives. The core of the ODD-Ex technique is the introduction of optimally shaped laser pulses to simultaneously enhance sensitivity to explosives signatures while dramatically improving specificity, particularly against matrix materials and background interferences. These goals are being addressed by operating in an optimal non-linear fashion, typically with a single shaped laser pulse inherently containing within it coherently locked control and probe subpulses. Recent results will be presented.

  18. The fluid dynamics of microjet explosions caused by extremely intense X-ray pulses

    Science.gov (United States)

    Stan, Claudiu; Laksmono, Hartawan; Sierra, Raymond; Milathianaki, Despina; Koglin, Jason; Messerschmidt, Marc; Williams, Garth; Demirci, Hasan; Botha, Sabine; Nass, Karol; Stone, Howard; Schlichting, Ilme; Shoeman, Robert; Boutet, Sebastien

    2014-11-01

    Femtosecond X-ray scattering experiments at free-electron laser facilities typically requires liquid jet delivery methods to bring samples to the region of interaction with X-rays. We have imaged optically the damage process in water microjets due to intense hard X-ray pulses at the Linac Coherent Light Source (LCLS), using time-resolved imaging techniques to record movies at rates up to half a billion frames per second. For pulse energies larger than a few percent of the maximum pulse energy available at LCLS, the X-rays deposit energies much larger than the latent heat of vaporization in water, and induce a phase explosion that opens a gap in the jet. The LCLS pulses last a few tens of femtoseconds, but the full evolution of the broken jet is orders of magnitude slower - typically in the microsecond range - due to complex fluid dynamics processes triggered by the phase explosion. Although the explosion results in a complex sequence of phenomena, they lead to an approximately self-similar flow of the liquid in the jet.

  19. Explosives 92. Conference proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Farnfield, R.A. (ed.)

    1992-01-01

    17 papers are presented. Topics covered include: the POG system - a new concept in the use of ANFO; demolition of a motorway bridge; presplit and smooth blasting; VIBReX - a predictive code for assessing the effect of blast design on ground vibration; ground vibrations from blasting; digital seismographs; human response to blasting and the effects on planning conditions; landform construction by restoration blasting; use of small diameter explosives; efficient priming; safety management in the explosives industry; and the law on packaging of explosives. Two papers have been abstracted separately.

  20. Effect of granosan vapors on mitosis

    Energy Technology Data Exchange (ETDEWEB)

    Lishenko, N P; Lishenko, I D

    1974-01-01

    Experiments were performed to determine the effects of granosan on the germination of vetch seeds. Vetch seeds were stored from 4-6 days in ethyl mercuric chloride vapors. Results indicated that the vapors caused a sharp decrease in germination and caused chromosomal aberrations during the anaphase.

  1. Steam explosion triggering and efficiency studies

    International Nuclear Information System (INIS)

    Buxton, L.D.; Nelson, L.S.; Benedick, W.B.

    1979-01-01

    Laboratory experiments on the thermal interaction of simulated light water reactor (LWR) fuel melts and water are summarized. Their purpose was to investigate the possibility of steam explosions occurring for a range of hypothetical accident conditions. Pressure, temperature, hot liquid motion and cold liquid motion were monitored during the experiments

  2. The control and prevention of dust explosions

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    Papers presented discussed: explosion characteristics and hybrid mixtures explosion characteristics and influencing factors, propagation of dust explosions in ducts, prevention of dust explosions, desensitization, explosion-proof type of construction, explosion pressure relief, optical flame barriers, slide-valves for explosion protection, Ventex explosion barrier valves, grinding and mixing plants, spray driers, dust explosions in silos, and explosion-proof bucket elevators. One paper has been abstracted separately.

  3. Seismic coupling of nuclear explosions. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Larson, D B [ed.; Defense Advanced Research Projects Agency, Arlington, VA (United States)

    1989-12-31

    The new Giant Magnet Experimental Facility employing digital recording of explosion induced motion has been constructed and successfully tested. Particle velocity and piezoresistance gage responses can be measured simultaneously thus providing the capability for determining the multi-component stress-strain history in the test material. This capability provides the information necessary for validation of computer models used in simulation of nuclear underground testing, chemical explosion testing, dynamic structural response, earth penetration response, and etc. This report discusses fully coupled and cavity decoupled explosions of the same energy (0.622 kJ) were carried out as experiments to study wave propagation and attenuation in polymethylmethacrylate (PMMA). These experiments produced particle velocity time histories at strains from 2 {times} 10{sup {minus}3} to as low as 5.8 {times} 10{sup {minus}6}. Other experiments in PMMA, reported recently by Stout and Larson{sup 8} provide additional particle velocity data to strains of 10{sup {minus}1}.

  4. Thermal explosion models

    Energy Technology Data Exchange (ETDEWEB)

    Ping, Tso Chin [Malaya Univ., Kuala Lumpur (Malaysia)

    1984-12-01

    The phenomenon of thermal explosion arises in several important safety problems, yet scientists are still baffled by its origin. This article reviews some of the models that have been proposed to explain the phenomenon.

  5. Thermal explosion models

    International Nuclear Information System (INIS)

    Tso Chin Ping

    1984-01-01

    The phenomenon of thermal explosion arises in several important safety problems, yet scientists are still baffled by its origin. This article reviews some of the models that have been proposed to explain the phenomenon. (author)

  6. Parametric Explosion Spectral Model

    Energy Technology Data Exchange (ETDEWEB)

    Ford, S R; Walter, W R

    2012-01-19

    Small underground nuclear explosions need to be confidently detected, identified, and characterized in regions of the world where they have never before occurred. We develop a parametric model of the nuclear explosion seismic source spectrum derived from regional phases that is compatible with earthquake-based geometrical spreading and attenuation. Earthquake spectra are fit with a generalized version of the Brune spectrum, which is a three-parameter model that describes the long-period level, corner-frequency, and spectral slope at high-frequencies. Explosion spectra can be fit with similar spectral models whose parameters are then correlated with near-source geology and containment conditions. We observe a correlation of high gas-porosity (low-strength) with increased spectral slope. The relationship between the parametric equations and the geologic and containment conditions will assist in our physical understanding of the nuclear explosion source.

  7. Ammonium nitrate explosion hazards

    Directory of Open Access Journals (Sweden)

    Negovanović Milanka

    2015-01-01

    Full Text Available Ammonium nitrate (AN primarily is used as a fertilizer but it is also very important compound in the production of industrial explosives. The application of ammonium nitrate in the production of industrial explosives was related with the early era of Nobel dynamite and widely increased with the appearance of blasting agents such as ANFO and Slurry, in the middle of the last Century. Throughout the world millions of tons of ammonium nitrate are produced annually and handled without incident. Although ammonium nitrate generally is used safely, accidental explosions involving AN have high impact resulting in loss of lives and destruction of property. The paper presents the basic properties of ammonium nitrate as well as hazards in handling of ammonium nitrate in order to prevent accidents. Several accidents with explosions of ammonium nitrate resulted in catastrophic consequences are listed in the paper as examples of non-compliance with prescribed procedures.

  8. Shock waves & explosions

    CERN Document Server

    Sachdev, PL

    2004-01-01

    Understanding the causes and effects of explosions is important to experts in a broad range of disciplines, including the military, industrial and environmental research, aeronautic engineering, and applied mathematics. Offering an introductory review of historic research, Shock Waves and Explosions brings analytic and computational methods to a wide audience in a clear and thorough way. Beginning with an overview of the research on combustion and gas dynamics in the 1970s and 1980s, the author brings you up to date by covering modeling techniques and asymptotic and perturbative methods and ending with a chapter on computational methods.Most of the book deals with the mathematical analysis of explosions, but computational results are also included wherever they are available. Historical perspectives are provided on the advent of nonlinear science, as well as on the mathematical study of the blast wave phenomenon, both when visualized as a point explosion and when simulated as the expansion of a high-pressure ...

  9. Intermittent Explosive Disorder

    Science.gov (United States)

    ... explosive disorder involves repeated, sudden episodes of impulsive, aggressive, violent behavior or angry verbal outbursts in which you react grossly out of proportion to the situation. Road rage, domestic abuse, throwing or breaking objects, or other temper tantrums ...

  10. Explosive Components Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The 98,000 square foot Explosive Components Facility (ECF) is a state-of-the-art facility that provides a full-range of chemical, material, and performance analysis...

  11. Idaho Explosives Detection System

    International Nuclear Information System (INIS)

    Reber, Edward L.; Blackwood, Larry G.; Edwards, Andrew J.; Jewell, J. Keith; Rohde, Kenneth W.; Seabury, Edward H.; Klinger, Jeffery B.

    2005-01-01

    The Idaho Explosives Detection System was developed at the Idaho National Laboratory (INL) to respond to threats imposed by delivery trucks potentially carrying explosives into military bases. A full-scale prototype system has been built and is currently undergoing testing. The system consists of two racks, one on each side of a subject vehicle. Each rack includes a neutron generator and an array of NaI detectors. The two neutron generators are pulsed and synchronized. A laptop computer controls the entire system. The control software is easily operable by minimally trained staff. The system was developed to detect explosives in a medium size truck within a 5-min measurement time. System performance was successfully demonstrated with explosives at the INL in June 2004 and at Andrews Air Force Base in July 2004

  12. Idaho Explosives Detection System

    Energy Technology Data Exchange (ETDEWEB)

    Reber, Edward L. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States)]. E-mail: reber@inel.gov; Blackwood, Larry G. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Edwards, Andrew J. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Jewell, J. Keith [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Rohde, Kenneth W. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Seabury, Edward H. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States); Klinger, Jeffery B. [Idaho National Laboratory, 2525 N. Freemont Ave., Idaho Falls, ID 83415-2114 (United States)

    2005-12-15

    The Idaho Explosives Detection System was developed at the Idaho National Laboratory (INL) to respond to threats imposed by delivery trucks potentially carrying explosives into military bases. A full-scale prototype system has been built and is currently undergoing testing. The system consists of two racks, one on each side of a subject vehicle. Each rack includes a neutron generator and an array of NaI detectors. The two neutron generators are pulsed and synchronized. A laptop computer controls the entire system. The control software is easily operable by minimally trained staff. The system was developed to detect explosives in a medium size truck within a 5-min measurement time. System performance was successfully demonstrated with explosives at the INL in June 2004 and at Andrews Air Force Base in July 2004.

  13. Intermittent Explosive Disorder

    Directory of Open Access Journals (Sweden)

    Lut Tamam

    2011-09-01

    Full Text Available Intermittent explosive disorder is an impulse control disorder characterized by the occurrence of discrete episodes of failure to resist aggressive impulses that result in violent assault or destruction of property. Though the prevalence intermittent explosive disorder has been reported to be relatively rare in frontier studies on the field, it is now common opinion that intermittent explosive disorder is far more common than previously thought especially in clinical psychiatry settings. Etiological studies displayed the role of both psychosocial factors like childhood traumas and biological factors like dysfunctional neurotransmitter systems and genetics. In differential diagnosis of the disorder, disorders involving agression as a symptom such as alcohol and drug intoxication, antisocial and borderline personality disorders, personality changes due to general medical conditions and behavioral disorder should be considered. A combination of pharmacological and psychotherapeutic approaches are suggested in the treatment of the disorder. This article briefly reviews the historical background, diagnostic criteria, epidemiology, etiology and treatment of intermittent explosive disorder.

  14. Five-component propagation model for steam explosion analysis

    International Nuclear Information System (INIS)

    Yang, Y.; Moriyama, Kiyofumi; Park, H.S.; Maruyama, Yu; Sugimoto, Jun

    1999-01-01

    A five-field simulation code JASMINE-pro has been developed at JAERI for the calculation of the propagation and explosion phase of steam explosions. The basic equations and the constitutive relationships specifically utilized in the propagation models in the code are introduced in this paper. Some calculations simulating the KROTOS 1D and 2D steam explosion experiments are also stated in the paper to show the present capability of the code. (author)

  15. Sensitivities of ionic explosives

    Science.gov (United States)

    Politzer, Peter; Lane, Pat; Murray, Jane S.

    2017-03-01

    We have investigated the relevance for ionic explosive sensitivity of three factors that have been demonstrated to be related to the sensitivities of molecular explosives. These are (1) the maximum available heat of detonation, (2) the amount of free space per molecule (or per formula unit) in the crystal lattice and (3) specific features of the electrostatic potential on the molecular or ionic surface. We find that for ionic explosives, just as for molecular ones, there is an overall tendency for impact sensitivity to increase as the maximum detonation heat release is greater. This means that the usual emphasis upon designing explosives with large heats of detonation needs to be tempered somewhat. We also show that a moderate detonation heat release does not preclude a high level of detonation performance for ionic explosives, as was already demonstrated for molecular ones. Relating the free space per formula unit to sensitivity may require a modified procedure for ionic explosives; this will continue to be investigated. Finally, an encouraging start has been made in linking impact sensitivities to the electrostatic potentials on ionic surfaces, although limited so far to ammonium salts.

  16. Relative source comparison of the NPE to underground nuclear explosions at local distances

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A.T. [Lawrence Livermore National Lab., CA (United States)

    1994-12-31

    The Non-Proliferation Experiment (NPE) provides an opportunity to compare broadband characteristics of chemical to nuclear explosions at a group of local stations (4 to 40 km distant). The locations for these stations were established on bedrock to record a small partially decoupled nuclear explosion and two nearby nuclear experiments, all shots within {open_quotes}N{close_quotes} Tunnel on Rainier Mesa, Area 12. These sites were also occupied to record aftershocks from the Little Skull Mountain earthquake and chemical explosions from the USGS Sierra Experiment. To minimize calibration errors during this period, redundant instrumentation were used for each event. THe analysis emphasizes the source characteristics of the different explosions. The 300-lb chemical calibration explosion allows removal of path effects from each explosion. The NPE and nearby experiments produce very similar waveforms. The decoupled nuclear explosion and the 300-lb chemical calibration explosion show higher frequency content consistent with a higher corner frequency for the sources.

  17. Steam explosion triggering and efficiency studies

    International Nuclear Information System (INIS)

    Buxton, L.D.; Nelson, L.S.; Benedick, W.B.

    1979-01-01

    A program at Sandia Laboratories to provide relevant data on the interaction of molten LWR core materials with water is described. Two different subtasks were established. The first was the performance of laboratory-scale experiments to investigate the ability to trigger steam explosions for realistic LWR core melt simulants under a wide range of initial conditions. The second was the performance of field-scale experiments to investigate the efficiency of converting the thermal energy of the melt into mechanical work in much larger steam explosions

  18. Ex-Vessel corium coolability and steam explosion energetics in nordic light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Dinh, T.N.; Ma, W.M.; Karbojian, A.; Kudinov, P.; Tran, C.T.; Hansson, C.R. [Royal Institute of Technology (KTH), (Sweden)

    2008-03-15

    This report presents advances and insights from the KTH's study on corium pool heat transfer in the BWR lower head; debris bed formation; steam explosion energetics; thermal hydraulics and coolability in bottom-fed and heterogeneous debris beds. Specifically, for analysis of heat transfer in a BWR lower plenum an advanced threedimensional simulation tool was developed and validated, using a so-called effective convectivity approach and Fluent code platform. An assessment of corium retention and coolability in the reactor pressure vessel (RPV) lower plenum by means of water supplied through the Control Rod Guide Tube (CRGT) cooling system was performed. Simulant material melt experiments were performed in an intermediate temperature range (1300-1600K) on DEFOR test facility to study formation of debris beds in high and low subcooled water pools characteristic of in-vessel and ex-vessel conditions. Results of the DEFOR-E scoping experiments and related analyses strongly suggest that porous beds formed in ex-vessel from a fragmented high-temperature debris is far from homogeneous. Calculation results of bed thermal hydraulics and dryout heat flux with a two-dimensional thermal-hydraulic code give the first basis to evaluate the extent by which macro and micro inhomogeneity can enhance the bed coolability. The development and validation of a model for two-phase natural circulation through a heated porous medium and its application to the coolability analysis of bottom-fed beds enables quantification of the significant effect of dryout heat flux enhancement (by a factor of 80-160%) due to bottom coolant injection. For a qualitative and quantitative understanding of steam explosion, the SHARP system and its image processing methodology were used to characterize the dynamics of a hot liquid (melt) drop fragmentation and the volatile liquid (coolant) vaporization. The experimental results provide a basis to suggest that the melt drop preconditioning is instrumental to

  19. Ex-Vessel corium coolability and steam explosion energetics in nordic light water reactors

    International Nuclear Information System (INIS)

    Dinh, T.N.; Ma, W.M.; Karbojian, A.; Kudinov, P.; Tran, C.T.; Hansson, C.R.

    2008-03-01

    This report presents advances and insights from the KTH's study on corium pool heat transfer in the BWR lower head; debris bed formation; steam explosion energetics; thermal hydraulics and coolability in bottom-fed and heterogeneous debris beds. Specifically, for analysis of heat transfer in a BWR lower plenum an advanced threedimensional simulation tool was developed and validated, using a so-called effective convectivity approach and Fluent code platform. An assessment of corium retention and coolability in the reactor pressure vessel (RPV) lower plenum by means of water supplied through the Control Rod Guide Tube (CRGT) cooling system was performed. Simulant material melt experiments were performed in an intermediate temperature range (1300-1600K) on DEFOR test facility to study formation of debris beds in high and low subcooled water pools characteristic of in-vessel and ex-vessel conditions. Results of the DEFOR-E scoping experiments and related analyses strongly suggest that porous beds formed in ex-vessel from a fragmented high-temperature debris is far from homogeneous. Calculation results of bed thermal hydraulics and dryout heat flux with a two-dimensional thermal-hydraulic code give the first basis to evaluate the extent by which macro and micro inhomogeneity can enhance the bed coolability. The development and validation of a model for two-phase natural circulation through a heated porous medium and its application to the coolability analysis of bottom-fed beds enables quantification of the significant effect of dryout heat flux enhancement (by a factor of 80-160%) due to bottom coolant injection. For a qualitative and quantitative understanding of steam explosion, the SHARP system and its image processing methodology were used to characterize the dynamics of a hot liquid (melt) drop fragmentation and the volatile liquid (coolant) vaporization. The experimental results provide a basis to suggest that the melt drop preconditioning is instrumental to the

  20. Thermal decomposition and reaction of confined explosives

    International Nuclear Information System (INIS)

    Catalano, E.; McGuire, R.; Lee, E.; Wrenn, E.; Ornellas, D.; Walton, J.

    1976-01-01

    Some new experiments designed to accurately determine the time interval required to produce a reactive event in confined explosives subjected to temperatures which will cause decomposition are described. Geometry and boundary conditions were both well defined so that these experiments on the rapid thermal decomposition of HE are amenable to predictive modelling. Experiments have been carried out on TNT, TATB and on two plastic-bonded HMX-based high explosives, LX-04 and LX-10. When the results of these experiments are plotted as the logarithm of the time to explosion versus 1/T K (Arrhenius plot), the curves produced are remarkably linear. This is in contradiction to the results obtained by an iterative solution of the Laplace equation for a system with a first order rate heat source. Such calculations produce plots which display considerable curvature. The experiments have also shown that the time to explosion is strongly influenced by the void volume in the containment vessel. Results of the experiments with calculations based on the heat flow equations coupled with first-order models of chemical decomposition are compared. The comparisons demonstrate the need for a more realistic reaction model

  1. Comparative study of the vapor analytes of trinitrotoluene (TNT)

    Science.gov (United States)

    Edge, Cindy C.; Gibb, Julie; Dugan, Regina E.

    1998-12-01

    Trinitrotoluene (TNT) is a high explosive used in most antipersonnel and antitank landmines. The Institute for Biological Detection Systems (IBDS) has developed a quantitative vapor delivery system, termed olfactometer, for conducting canine olfactory research. The research is conducted utilizing dynamic conditions, therefore, it is imperative to evaluate the headspace of TNT to ensure consistency with the dynamic generation of vapor. This study quantified the vapor headspace of military- grade TNT utilizing two different vapor generated methodologies, static and dynamic, reflecting differences between field and laboratory environments. Static vapor collection, which closely mimics conditions found during field detection, is defined as vapor collected in an open-air environment at ambient temperature. Dynamic vapor collection incorporates trapping of gases from a high flow vapor generation cell used during olfactometer operation. Analysis of samples collected by the two methodologies was performed by gas chromatography/mass spectrometry and the results provided information with regard to the constituents detected. However, constituent concentration did vary between the sampling methods. This study provides essential information regarding the vapor constituents associated with the TNT sampled using different sampling methods. These differences may be important in determining the detection signature dogs use to recognize TNT.

  2. Experimental study of detonation of large-scale powder-droplet-vapor mixtures

    Science.gov (United States)

    Bai, C.-H.; Wang, Y.; Xue, K.; Wang, L.-F.

    2018-05-01

    Large-scale experiments were carried out to investigate the detonation performance of a 1600-m3 ternary cloud consisting of aluminum powder, fuel droplets, and vapor, which were dispersed by a central explosive in a cylindrically stratified configuration. High-frame-rate video cameras and pressure gauges were used to analyze the large-scale explosive dispersal of the mixture and the ensuing blast wave generated by the detonation of the cloud. Special attention was focused on the effect of the descending motion of the charge on the detonation performance of the dispersed ternary cloud. The charge was parachuted by an ensemble of apparatus from the designated height in order to achieve the required terminal velocity when the central explosive was detonated. A descending charge with a terminal velocity of 32 m/s produced a cloud with discernably increased concentration compared with that dispersed from a stationary charge, the detonation of which hence generates a significantly enhanced blast wave beyond the scaled distance of 6 m/kg^{1/3}. The results also show the influence of the descending motion of the charge on the jetting phenomenon and the distorted shock front.

  3. Nondestructive test for assembly relationship of initiating explosive device

    International Nuclear Information System (INIS)

    Wang Xiangang; Zhang Chaozong; Guo Zhiping

    2009-01-01

    A 3D computed tomography (CT) method to inspect assembly relationship of initiating explosive device and to nondestructively evaluate assembly relationship by building geometric model from CT images was described. The experiment result proves that this method accurately inspects assembly relationship of initiating explosive device. (authors)

  4. Condensation of vapor bubble in subcooled pool

    Science.gov (United States)

    Horiuchi, K.; Koiwa, Y.; Kaneko, T.; Ueno, I.

    2017-02-01

    We focus on condensation process of vapor bubble exposed to a pooled liquid of subcooled conditions. Two different geometries are employed in the present research; one is the evaporation on the heated surface, that is, subcooled pool boiling, and the other the injection of vapor into the subcooled pool. The test fluid is water, and all series of the experiments are conducted under the atmospheric pressure condition. The degree of subcooling is ranged from 10 to 40 K. Through the boiling experiment, unique phenomenon known as microbubble emission boiling (MEB) is introduced; this phenomenon realizes heat flux about 10 times higher than the critical heat flux. Condensation of the vapor bubble is the key phenomenon to supply ambient cold liquid to the heated surface. In order to understand the condensing process in the MEB, we prepare vapor in the vapor generator instead of the evaporation on the heated surface, and inject the vapor to expose the vapor bubble to the subcooled liquid. Special attention is paid to the dynamics of the vapor bubble detected by the high-speed video camera, and on the enhancement of the heat transfer due to the variation of interface area driven by the condensation.

  5. The Zugspitze radiative closure experiment for quantifying water vapor absorption over the terrestrial and solar infrared – Part 3: Quantification of the mid- and near-infrared water vapor continuum in the 2500 to 7800 cm−1 spectral range under atmospheric conditions

    Directory of Open Access Journals (Sweden)

    A. Reichert

    2016-09-01

    Full Text Available We present a first quantification of the near-infrared (NIR water vapor continuum absorption from an atmospheric radiative closure experiment carried out at the Zugspitze (47.42° N, 10.98° E; 2964 m a.s.l.. Continuum quantification is achieved via radiative closure using radiometrically calibrated solar Fourier transform infrared (FTIR absorption spectra covering the 2500 to 7800 cm−1 spectral range. The dry atmospheric conditions at the Zugspitze site (IWV 1.4 to 3.3 mm enable continuum quantification even within water vapor absorption bands, while upper limits for continuum absorption can be provided in the centers of window regions. Throughout 75 % of the 2500 to 7800 cm−1 spectral range, the Zugspitze results agree within our estimated uncertainty with the widely used MT_CKD 2.5.2 model (Mlawer et al., 2012. In the wings of water vapor absorption bands, our measurements indicate about 2–5 times stronger continuum absorption than MT_CKD, namely in the 2800 to 3000 cm−1 and 4100 to 4200 cm−1 spectral ranges. The measurements are consistent with the laboratory measurements of Mondelain et al. (2015, which rely on cavity ring-down spectroscopy (CDRS, and the calorimetric–interferometric measurements of Bicknell et al. (2006. Compared to the recent FTIR laboratory studies of Ptashnik et al. (2012, 2013, our measurements are consistent within the estimated errors throughout most of the spectral range. However, in the wings of water vapor absorption bands our measurements indicate typically 2–3 times weaker continuum absorption under atmospheric conditions, namely in the 3200 to 3400, 4050 to 4200, and 6950 to 7050 cm−1 spectral regions.

  6. Novel high explosive compositions

    Science.gov (United States)

    Perry, D.D.; Fein, M.M.; Schoenfelder, C.W.

    1968-04-16

    This is a technique of preparing explosive compositions by the in-situ reaction of polynitroaliphatic compounds with one or more carboranes or carborane derivatives. One or more polynitroaliphatic reactants are combined with one or more carborane reactants in a suitable container and mixed to a homogeneous reaction mixture using a stream of inert gas or conventional mixing means. Ordinarily the container is a fissure, crack, or crevice in which the explosive is to be implanted. The ratio of reactants will determine not only the stoichiometry of the system, but will effect the quality and quantity of combustion products, the explosive force obtained as well as the impact sensitivity. The test values can shift with even relatively slight changes or modifications in the reaction conditions. Eighteen illustrative examples accompany the disclosure. (46 claims)

  7. Explosive mechanism of metal destruction by intense electromagnetic radiation flux

    International Nuclear Information System (INIS)

    Martynyuk, M.M.

    1977-01-01

    The metal destruction by a powerful flux of electromagnetic radiation is considered on the basis of thermodynamics and kinetics of the transition of molten metal to vapour during its rapid heating. The possibility is discussed of obtaining a metastable liquid-metal phase and of its explosion transition to a stable two-phase state (phase explosion of metastable liquid). It has been shown that at densities of radiation beam ensuring the heating of the metal to the spinodal point Tsub(s) during a time tsub(s)=10 -5 -10 -7 s the vaporization of the matter from the surface of the liquid is negligible, and the main mechanism of the metal destruction is the phase explosion of the metastable liquid-metal phase which originates in the Tsub(s) vicinity. The experimental data on the electric explosion of conductors for tsub(s)=10 -6 -10 -5 s has served as a basis for calculating the excess enthalpy and the proportion of the vapour phase formed in the phase explosion of Cu, Ag, Au, Zn, Cd, Al, Pb, Zr, Nb, Mo, W, Pt and Re. The particularities of the phase explosion at flux densities corresponding to tsub(s)( -8 s are considered

  8. High-nitrogen explosives

    Energy Technology Data Exchange (ETDEWEB)

    Naud, D. (Darren); Hiskey, M. A. (Michael A.); Kramer, J. F. (John F.); Bishop, R. L. (Robert L.); Harry, H. H. (Herbert H.); Son, S. F. (Steven F.); Sullivan, G. K. (Gregg K.)

    2002-01-01

    The syntheses and characterization of various tetrazine and furazan compounds offer a different approach to explosives development. Traditional explosives - such as TNT or RDX - rely on the oxidation of the carbon and hydrogen atoms by the oxygen carrying nitro group to produce the explosive energy. High-nitrogen compounds rely instead on large positive heats of formation for that energy. Some of these high-nitrogen compounds have been shown to be less sensitive to initiation (e.g. by impact) when compared to traditional nitro-containing explosives of similar performances. Using the precursor, 3,6-bis-(3,5-dimethylpyrazol-1-yl)-s-tetrazine (BDT), several useful energetic compounds based on the s-tetrazine system have been synthesized and studied. The compound, 3,3{prime}-azobis(6-amino-s-tetrazine) or DAAT, detonates as a half inch rate stick despite having no oxygen in the molecule. Using perfluoroacetic acid, DAAT can be oxidized to give mixtures of N-oxide isomers (DAAT03.5) with an average oxygen content of about 3.5. This energetic mixture burns at extremely high rates and with low dependency on pressure. Another tetrazine compound of interest is 3,6-diguanidino-s-tetrazine(DGT) and its dinitrate and diperchlorate salts. DGT is easily synthesized by reacting BDT with guanidine in methanol. Using Caro's acid, DGT can be further oxidized to give 3,6-diguanidino-s-tetrazine-1,4-di-N-oxide (DGT-DO). Like DGT, the di-N-oxide can react with nitric acid or perchloric acid to give the dinitrate and the diperchlorate salts. The compounds, 4,4{prime}-diamino-3,3{prime}-azoxyfurazan (DAAF) and 4,4{prime}-diamino-3,3{prime}-azofurazan (DAAzF), may have important future roles in insensitive explosive applications. Neither DAAF nor DAAzF can be initiated by laboratory impact drop tests, yet both have in some aspects better explosive performances than 1,3,5-triamino-2,4,6-trinitrobenzene TATB - the standard of insensitive high explosives. The thermal stability of DAAz

  9. Chernobyl: Anatomy of the explosion

    International Nuclear Information System (INIS)

    Lvov, G.

    1992-01-01

    On Friday, 26 April 1986, it was planned to shut down the fourth unit of the Chernobyl Atomic Power Station, U.S.S.R., for periodic maintenance. The procedure supplied the opportunity to perform a further experiment; operation of the turbine in free rotation regime, which occurs when the steam is cut down while the turbine is still running. It so happened that carrying out this experiment turned out to be the worst accident in the history of nuclear power industry. The first part of the article proceeds to a second by second detailed analysis of the causes of the catastrophe. The analysis uses official data and reports. The author covers the sequence of events, which led up to two explosions in the second hour of that tragic morning. In the second part of the article, the author provides hints and suggestions, so that 'the tragedy of Chernobyl does not become a useless lesson'. With regard to what, so far, has been published, the novelty of the article may be a diagram showing the excessive changes that affected the main parameters (power, water flow through circulating pumps, steam pressure in separators, and length of the immersed part of control rods) in the fourth unit during the last seconds before the explosion. If may be noteworthy to mention that the curves supplied here are based on data stored in the computer 'SCALA'. 2 figs

  10. Explosive material treatment in particular the explosive compaction of powders

    International Nuclear Information System (INIS)

    Pruemmer, R.

    1985-01-01

    The constructive use of explosives in the last decades has led to new procedures in manufacturing techniques. The most important of these are explosive forming and cladding, the latter especially for the production of compound materials. The method of explosive compaction has the highest potential for further innovation. Almost theoretical densities are achievable in the green compacts as the pressure released by detonating explosives are very high. Also, the production of new conditions of materials (metastable high pressure phases) is possible. (orig.) [de

  11. Seismic explosion sources on an ice cap

    DEFF Research Database (Denmark)

    Shulgin, Alexey; Thybo, Hans

    2015-01-01

    crustal model can be modelled. A crucial challenge for applying the technique is to control the sources. Here, we present data that describe the efficiency of explosive sources in the ice cover. Analysis of the data shows, that the ice cap traps a significant amount of energy, which is observed......Controlled source seismic investigation of crustal structure below ice covers is an emerging technique. We have recently conducted an explosive refraction/wide-angle reflection seismic experiment on the ice cap in east-central Greenland. The data-quality is high for all shot points and a full...

  12. 75 FR 1085 - Commerce in Explosives; List of Explosive Materials (2009R-18T)

    Science.gov (United States)

    2010-01-08

    ... sensitive slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting powder. BTNEC [bis.... Explosive conitrates. Explosive gelatins. Explosive liquids. Explosive mixtures containing oxygen-releasing... powder. Fulminate of mercury. Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating...

  13. 75 FR 70291 - Commerce in Explosives; List of Explosive Materials (2010R-27T)

    Science.gov (United States)

    2010-11-17

    ..., including non-cap sensitive slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting.... Explosive conitrates. Explosive gelatins. Explosive liquids. Explosive mixtures containing oxygen-releasing... powder. Fulminate of mercury. Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating...

  14. The concept of explosives malfunctioning in rock blasting

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Q.

    1993-11-01

    The purpose is to identify the critical conditions that cause malfunctioning for some commonly used explosives. Experiments are described that measure sympathetic detonation, desensitization, and cut-offs for two variables: spacing and delay. Explosive malfunctioning is depicted on a delay spacing chart that has different regions. On the chart, the shape and size of each region can vary from one explosive to another. Results are presented from over 70 blasts, that were conducted in the underground drift at the CANMET Experimental Mine, to identify the malfunctioning characteristics of specific emulsion, water gel, and dynamite explosives. For each experiment, two parallel blastholes (with diameter of 32 mm and depth of 1.7 m) were drilled downwards, and full coupling was achieved. The results are presented for the three types of explosives tested. 11 refs., 7 figs.

  15. Explosives trace detection in the process of biometrical fingerprint identification for access control

    Science.gov (United States)

    Bertseva, Elena V.; Savin, Andrey V.

    2007-02-01

    A method for trace detection of explosives on the surface of biometric fingerprint scanner is proposed and its sensitivity explored. The method is based on attenuated total reflection mid-infrared spectroscopy. The detection limit is about several microgram and the detectivity increases with the wavelength used for scanning. The advantages of the proposed method include high selectivity and thus low false alarm level, applicability to low vapor pressure explosives and low cost.

  16. Emission of Gas and Al2O3 Smoke in Gas-Al Particle Deflagration: Experiments and Emission Modeling for Explosive Fireballs

    Science.gov (United States)

    Ranc-Darbord, Isabelle; Baudin, Gérard; Genetier, Marc; Ramel, David; Vasseur, Pierre; Legrand, Julien; Pina, Vincent

    2018-03-01

    Emission of gas and Al2O3 smoke within the deflagration of H2{-}O2-{N2{-}CO2}-Al particles has been studied in a closed combustion chamber at pressures of up to 18 bar and at gas temperatures of up to 3700 K. Measurements of radiance intensity were taken using a five wavelength pyrometer (0.660 μ m, 0.850 μ m, 1.083 μ m, 1.260 μ m, 1.481 μ m) and a grating spectrometer in the range (4.10 μ m to 4.30 μ m). In order to characterize the aluminum oxide smoke size and temperature, an inversion method has been developed based on the radiation transfer equation and using pyrometer measurements and thermochemical calculations of Al2O3 smoke volume fractions. Temperatures in combustion gas have been determined using a method based on the assumed blackbody head of the 4.26 μ m CO2 emission line and on its spectral shift with pressure and temperature. For validation purpose, this method has been applied to measurements obtained when calibrated alumina particles are injected in a combustion chamber prior to gaseous deflagrations. This mathematical inversion method was developed to investigate explosive fireballs.

  17. Shock Initiation of Damaged Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; Vandersall, K S; Tarver, C M

    2009-10-22

    Explosive and propellant charges are subjected to various mechanical and thermal insults that can increase their sensitivity over the course of their lifetimes. To quantify this effect, shock initiation experiments were performed on mechanically and thermally damaged LX-04 (85% HMX, 15% Viton by weight) and PBX 9502 (95% TATB, 5% Kel-F by weight) to obtain in-situ manganin pressure gauge data and run distances to detonation at various shock pressures. We report the behavior of the HMX-based explosive LX-04 that was damaged mechanically by applying a compressive load of 600 psi for 20,000 cycles, thus creating many small narrow cracks, or by cutting wedge shaped parts that were then loosely reassembled, thus creating a few large cracks. The thermally damaged LX-04 charges were heated to 190 C for long enough for the beta to delta solid - solid phase transition to occur, and then cooled to ambient temperature. Mechanically damaged LX-04 exhibited only slightly increased shock sensitivity, while thermally damaged LX-04 was much more shock sensitive. Similarly, the insensitive explosive PBX 9502 was mechanically damaged using the same two techniques. Since PBX 9502 does not undergo a solid - solid phase transition but does undergo irreversible or 'rachet' growth when thermally cycled, thermal damage to PBX 9502 was induced by this procedure. As for LX-04, the thermally damaged PBX 9502 demonstrated a greater shock sensitivity than mechanically damaged PBX 9502. The Ignition and Growth reactive flow model calculated the increased sensitivities by igniting more damaged LX-04 and PBX 9502 near the shock front based on the measured densities (porosities) of the damaged charges.

  18. Explosive composition containing water

    Energy Technology Data Exchange (ETDEWEB)

    Cattermole, G.R.; Lyerly, W.M.; Cummings, A.M.

    1971-11-26

    This addition to Fr. 1,583,223, issued 31 May 1968, describes an explosive composition containing a water in oil emulsion. The composition contains an oxidizing mineral salt, a nitrate base salt as sensitizer, water, an organic fuel, a lipophilic emulsifier, and incorporates gas bubbles. The composition has a performance which is improved over and above the original patent.

  19. 75 FR 5545 - Explosives

    Science.gov (United States)

    2010-02-03

    ... the Storage of Ammonium Nitrate. OSHA subsequently made several minor revisions to the standard (37 FR... explosives; storing ammonium nitrate; and storing small arms ammunition, small arms primers, and small arms..., which is extremely widespread, causes lung disease, silicosis and lung cancer. Terminating the...

  20. New slurry explosives

    Energy Technology Data Exchange (ETDEWEB)

    Kale, D.C.

    1982-12-01

    Mining engineers will soon have an additional 2 or 3 types of explosives which increase rock yield without increasing cost. A new variety of Ammonium Nitrate and Fuel Oil (ANFO), which is much heavier and more powerful, is being introduced in the US. New types of NCN (nitrocarbonitrate) blasting agents have also been developed.

  1. Coulomb explosion of “hot spot”

    Energy Technology Data Exchange (ETDEWEB)

    Oreshkin, V. I., E-mail: oreshkin@ovpe.hcei.tsc.ru [Institute of High Current Electrons, SB, RAS, Tomsk (Russian Federation); Tomsk Polytechnic University, Tomsk (Russian Federation); Oreshkin, E. V. [P. N. Lebedev Physical Institute, RAS, Moscow (Russian Federation); Chaikovsky, S. A. [Institute of High Current Electrons, SB, RAS, Tomsk (Russian Federation); P. N. Lebedev Physical Institute, RAS, Moscow (Russian Federation); Institute of Electrophysics, UD, RAS, Ekaterinburg (Russian Federation); Artyomov, A. P. [Institute of High Current Electrons, SB, RAS, Tomsk (Russian Federation)

    2016-09-15

    The study presented in this paper has shown that the generation of hard x rays and high-energy ions, which are detected in pinch implosion experiments, may be associated with the Coulomb explosion of the hot spot that is formed due to the outflow of the material from the pinch cross point. During the process of material outflow, the temperature of the hot spot plasma increases, and conditions arise for the plasma electrons to become continuously accelerated. The runaway of electrons from the hot spot region results in the buildup of positive space charge in this region followed by a Coulomb explosion. The conditions for the hot spot plasma electrons to become continuously accelerated have been revealed, and the estimates have been obtained for the kinetic energy of the ions generated by the Coulomb explosion.

  2. Coulomb explosion of “hot spot”

    International Nuclear Information System (INIS)

    Oreshkin, V. I.; Oreshkin, E. V.; Chaikovsky, S. A.; Artyomov, A. P.

    2016-01-01

    The study presented in this paper has shown that the generation of hard x rays and high-energy ions, which are detected in pinch implosion experiments, may be associated with the Coulomb explosion of the hot spot that is formed due to the outflow of the material from the pinch cross point. During the process of material outflow, the temperature of the hot spot plasma increases, and conditions arise for the plasma electrons to become continuously accelerated. The runaway of electrons from the hot spot region results in the buildup of positive space charge in this region followed by a Coulomb explosion. The conditions for the hot spot plasma electrons to become continuously accelerated have been revealed, and the estimates have been obtained for the kinetic energy of the ions generated by the Coulomb explosion.

  3. Plasma Discharge Initiation of Explosives in Rock Blasting Application: A Case Study

    International Nuclear Information System (INIS)

    Chae, Jae-Ou; Jeong, Young-Jun; Shmelev, V M; Denicaev, A A; Poutchkov, V M; Ravi, V

    2006-01-01

    A plasma discharge initiation system for the explosive volumetric combustion charge was designed, investigated and developed for practical application. Laboratory scale experiments were carried out before conducting the large scale field tests. The resultant explosions gave rise to less noise, insignificant seismic vibrations and good specific explosive consumption for rock blasting. Importantly, the technique was found to be safe and environmentally friendly

  4. Seasonal and global behavior of water vapor in the Mars atmosphere: Complete global results of the Viking atmospheric water detector experiment

    International Nuclear Information System (INIS)

    Jakosky, B.M.; Farmer, C.B.

    1982-01-01

    The water vapor content of the Mars atmosphere was measured from the Viking Orbiter Mars Atmospheric Water Detectors (MAWD) for a period of more than 1 Martian year, from June 1976 through April 1979. Results are presented in the form of global maps of column abundance for 24 periods throughout each Mars year. The data reduction incorporates spatial and seasonal variations in surface pressure and supplements earlier published versions of less complete data

  5. Multi-scale fracture damage associated with underground chemical explosions

    Science.gov (United States)

    Swanson, E. M.; Sussman, A. J.; Wilson, J. E.; Townsend, M. J.; Prothro, L. B.; Gang, H. E.

    2018-05-01

    Understanding rock damage induced by explosions is critical for a number of applications including the monitoring and verification of underground nuclear explosions, mine safety issues, and modeling fluid flow through fractured rock. We use core observations, televiewer logs, and thin section observations to investigate fracture damage associated with two successive underground chemical explosions (SPE2 and SPE3) in granitic rock at both the mesoscale and microscale. We compare the frequency and orientations of core-scale fractures, and the frequency of microfractures, between a pre-experiment core and three post-experiment cores. Natural fault zones and explosion-induced fractures in the vicinity of the explosive source are readily apparent in recovered core and in thin sections. Damage from faults and explosions is not always apparent in fracture frequency plots from televiewer logs, although orientation data from these logs suggests explosion-induced fracturing may not align with the pre-existing fracture sets. Core-scale observations indicate the extent of explosion-induced damage is 10.0 m after SPE2 and 6.8 m after SPE3, despite both a similar size and location for both explosions. At the microscale, damage is observed to a range distance of 10.2 ± 0.9 m after SPE2, and 16.6 ± 0.9 and 11.2 ± 0.6 in two different cores collected after SPE3. Additional explosion-induced damage, interpreted to be the result of spalling, is readily apparent near the surface, but only in the microfracture data. This depth extent and intensity of damage in the near-surface region also increased after an additional explosion. This study highlights the importance of evaluating structural damage at multiple scales for a more complete characterization of the damage, and particularly shows the importance of microscale observations for identifying spallation-induced damage.

  6. Fuel vapor pressure (FVAPRS)

    International Nuclear Information System (INIS)

    Mason, R.E.

    1979-04-01

    A subcode (FVAPRS) is described which calculates fuel vapor pressure. This subcode was developed as part of the fuel rod behavior modeling task performed at EG and G Idaho, Inc. The fuel vapor pressure subcode (FVAPRS), is presented and a discussion of literature data, steady state and transient fuel vapor pressure equations and estimates of the standard error of estimate to be expected with the FVAPRS subcode are included

  7. Vapor Pressure of Antimony Triiodide

    Science.gov (United States)

    2017-12-07

    unlimited. iii Contents List of Figures iv 1. Introduction 1 2. Vapor Pressure 1 3. Experiment 3 4. Discussion and Measurements 5 5...SbI3 as a function of temperature ......................... 6 Approved for public release; distribution is unlimited. 1 1. Introduction ...single-crystal thin films of n-type (Bi,Sb)2(Te,Se)3 materials presents new doping challenges because it is a nonequilibrium process. (Bi,Sb)2(Te,Se)3

  8. Nano-powder production by electrical explosion of wires

    International Nuclear Information System (INIS)

    Mao Zhiguo; Zou Xiaobing; Wang Xinxin; Jiang Weihua

    2010-01-01

    A device for nano-powder production by electrical explosion of wires was designed and built. Eight wires housed in the discharge chamber are exploded one by one before opening the chamber for the collection of the produced nano-powder. To increase the rate of energy deposition into a wire, the electrical behavior of the discharge circuit including the exploding wire was simulated. The results showed that both reducing the circuit inductance and reducing the capacitance of the energy-storage capacitor (keeping the storage energy constant) can increase the energy deposition rate. To better understand the physical processes of the nano-powder formation by the wire vapor, a Mach-Zehnder interferometer was used to record the time evolution of the wire vapor as well as the plasma. A thermal expansion lag of the dense vapor core as well as more than one times of the vapor burst was observed for the first time. Finally, nano-powders of titanium nitride, titanium dioxide, copper oxides and zinc oxide were produced by electrical explosion of wires. (authors)

  9. Dynamic Fracture Simulations of Explosively Loaded Cylinders

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Carly W. [Univ. of California, Davis, CA (United States). Dept. of Civil and Environmental Engineering; Goto, D. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-11-30

    This report documents the modeling results of high explosive experiments investigating dynamic fracture of steel (AerMet® 100 alloy) cylinders. The experiments were conducted at Lawrence Livermore National Laboratory (LLNL) during 2007 to 2008 [10]. A principal objective of this study was to gain an understanding of dynamic material failure through the analysis of hydrodynamic computer code simulations. Two-dimensional and three-dimensional computational cylinder models were analyzed using the ALE3D multi-physics computer code.

  10. Development of the colorimetric sensor array for detection of explosives and volatile organic compounds in air

    DEFF Research Database (Denmark)

    Kostesha, Natalie; Alstrøm, Tommy Sonne; Johnsen, C

    2010-01-01

    a color difference map which gives a unique fingerprint for each explosive and volatile organic compound. Such sensing technology can be used to screen for relevant explosives in a complex background as well as to distinguish mixtures of volatile organic compounds distributed in gas phase. This sensor......In the framework of the research project 'Xsense' at the Technical University of Denmark (DTU) we are developing a simple colorimetric sensor array which can be useful in detection of explosives like DNT and TNT, and identification of volatile organic compounds in the presence of water vapor in air...

  11. Services Textbook of Explosives

    Science.gov (United States)

    1972-03-01

    the propagation in such systems of the detonation wave which had been observed in 1881 by Berthelot and Vieille and by Mallard and le Chatelier . In...detonation, Berthelot and Le Chatelier , Dautrich 4 - 63: Calorometric value 4 -- 66, Power of explosive, lead block, Trauzl 4 - 67- Ballistic pendulum 4...the principles of electric ignition were applied to this system also. 75. In 1890-91 Curtius first prepared lead, silver and mercury azides. The

  12. Charging method of water hole with ANFO explosive

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Susumu

    1988-02-28

    It has been investigated how to charge a water hole with an inexpensive explosive for blasting. An experiment was made using the combination of a plasticized resin hose and the ANFO charger as the method for making the most of the ANFO explosive aiming at charging a hole with the explosive at a low cost without damaging the hole wall. The experimental result indicates that any water hole with spring water can be charged with the explosive using the ANFO charger combined with the plasticized resin hose. The method is superior to conventional methods in cost and workability because the working atmosphere is not aggravated and the hole wall is not damaged without using an expensive vacuum collector. Charging a blasting hole 165 mm or less in diameter with the explosive will be investigated for commercialization in future. (4 figs)

  13. Petroleum Vapor - Field Technical

    Science.gov (United States)

    The screening approach being developed by EPA OUST to evaluate petroleum vapor intrusion (PVI) requires information that has not be routinely collected in the past at vapor intrusion sites. What is the best way to collect this data? What are the relevant data quality issues and ...

  14. Modelling and simulation of gas explosions in complex geometries

    Energy Technology Data Exchange (ETDEWEB)

    Saeter, Olav

    1998-12-31

    This thesis presents a three-dimensional Computational Fluid Dynamics (CFD) code (EXSIM94) for modelling and simulation of gas explosions in complex geometries. It gives the theory and validates the following sub-models : (1) the flow resistance and turbulence generation model for densely packed regions, (2) the flow resistance and turbulence generation model for single objects, and (3) the quasi-laminar combustion model. It is found that a simple model for flow resistance and turbulence generation in densely packed beds is able to reproduce the medium and large scale MERGE explosion experiments of the Commission of European Communities (CEC) within a band of factor 2. The model for a single representation is found to predict explosion pressure in better agreement with the experiments with a modified k-{epsilon} model. This modification also gives a slightly improved grid independence for realistic gas explosion approaches. One laminar model is found unsuitable for gas explosion modelling because of strong grid dependence. Another laminar model is found to be relatively grid independent and to work well in harmony with the turbulent combustion model. The code is validated against 40 realistic gas explosion experiments. It is relatively grid independent in predicting explosion pressure in different offshore geometries. It can predict the influence of ignition point location, vent arrangements, different geometries, scaling effects and gas reactivity. The validation study concludes with statistical and uncertainty analyses of the code performance. 98 refs., 96 figs, 12 tabs.

  15. Experiment for deep seismic reflections in Hidaka, Hokkaido. Comparison between Vibroseis and explosive data; Hidaka chiiki ni okeru shinbu hanno data no shutoku jikken. Vibroseis to dynamite no hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, N; Ikawa, T [Japex Jeoscience Institute, Tokyo (Japan); Ito, T; Tsumura, N; Shinohara, M; Ikawa, T. Ikawa, H.; Asano, Y; Tanaka, Y; Miyazono, N [Chiba University, Chiba (Japan); Arita, K; Moriya, T; Otsuka, K; Omura, T [Hokkaido University, Sapporo (Japan); Kimura, M [Osaka Prefectural University, Osaka (Japan); Hirata, N [The University of Tokyo, Tokyo (Japan); Okuike, S

    1997-05-27

    This is a prompt report. These days the importance of acquiring knowledge about the structure from the lower crust down to the upper mantle is often discussed with reference taken to Hyogo-ken Nanbu Earthquake. The Hidaka collision belt where the lower crust is exposed on the surface is a rare phenomenon in the world and has been the subject of seismic survey. As a part of the survey, experiments are conducted by the use of vibrations produced by Vibroseis and dynamite sources. Every one of the shot records (20-second record) from the two types of vibration sources contains a clear echo in the vicinity of 16 seconds supposedly from a level deeper than 40 kilometers, not to mention reflections from shallow levels. Although some studies have to be conducted before the reflecting geological boundary (possibly the upper mantle) of the echo near the 16-second point can be identified, yet this is probably the reflection from the deepest level ever obtained in the seismic reflection survey conducted in Japan`s land area. It is proved by this experiment that vibration from a vibrator can reach as far as that from explosion if the vibrator specifications are rightly chosen. 4 refs., 3 figs.

  16. Thermal-hydraulic behaviors of vapor-liquid interface due to arrival of a pressure wave

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Akira; Fujii, Yoshifumi; Matsuzaki, Mitsuo [Tokyo Institute of Technology (Japan)

    1995-09-01

    In the vapor explosion, a pressure wave (shock wave) plays a fundamental role for triggering, propagation and enhancement of the explosion. Energy of the explosion is related to the magnitude of heat transfer rate from hot liquid to cold volatile one. This is related to an increasing rate of interface area and to an amount of transient heat flux between the liquids. In this study, the characteristics of transient heat transfer and behaviors of vapor film both on the platinum tube and on the hot melt tin drop, under same boundary conditions have been investigated. It is considered that there exists a fundamental mechanism of the explosion in the initial expansion process of the hot liquid drop immediately after arrival of pressure wave. The growth rate of the vapor film is much faster on the hot liquid than that on the solid surface. Two kinds of roughness were observed, one due to the Taylor instability, by rapid growth of the explosion bubble, and another, nucleation sites were observed at the vapor-liquid interface. Based on detailed observation of early stage interface behaviors after arrival of a pressure wave, the thermal fragmentation mechanism is proposed.

  17. Calculational model for condensation of water vapor during an underground nuclear detonation

    International Nuclear Information System (INIS)

    Knox, R.J.

    1975-01-01

    An empirally derived mathematical model was developed to calculate the pressure and temperature history during condensation of water vapor in an underground-nuclear-explosion cavity. The condensation process is non-isothermal. Use has been made of the Clapeyron-Clausius equation as a basis for development of the model. Analytic fits to the vapor pressure and the latent heat of vaporization for saturated-water vapor, together with an estimated value for the heat-transfer coefficient, have been used to describe the phenomena. The calculated pressure-history during condensation has been determined to be exponential, with a time constant somewhat less than that observed during the cooling of the superheated steam from the explosion. The behavior of the calculated condensation-pressure compares well with the observed-pressure record (until just prior to cavity collapse) for a particular nuclear-detonation event for which data is available

  18. Response of Radon in a seismic calibration explosion, Israel

    International Nuclear Information System (INIS)

    Zafrir, H.; Steinitz, G.; Malik, U.; Haquin, G.; Gazit-Yaari, N.

    2009-01-01

    Radon measurements were performed at shallow levels during an in-land 20-ton seismic calibration explosion experiment, simulating a 2.6-M L earthquake, to investigate the influence of the explosive blast and the transitory seismic wave fields on the Radon transport in the country rock, adjacent to the focus of the explosion. The experiment was conducted in a basalt quarry in the northern margin of the Beit Shean valley (Israel). Five gamma-ray sensors were placed, at a depth of about 2 m, along a line located 17-150 m from the edge of the explosion zone. Measurements commenced 4 days before and continued for 9 days after the explosion with 15 min integrations. A 10-s sampling was used in the interval of several hours before and after the explosion itself. Diurnal variations of Radon, reflecting the typical variation pattern of Radon in the shallow environment, were registered before and after the explosion. No significant change in the overall Radon concentration was observed as a consequence of the main explosion as well as three smaller experimental shots (0.5-2 tons) in the 2 h prior to the calibration blast. The seismological data indicate that the transient excess pressure at the farthest Radon sensor was above 5 bar m -1 during 0.2-0.4 s, and evidently much higher at the nearest sensors, but none of the sensors responded by recording any exceptional change in the Radon concentration. Moreover the hypothesis that additional Radon may emanate from solid grains as a result of the excess local pressure exerted by the blast is also not observed. In contrast to a real earthquake event an explosion experiment has neither eventual preceding nor following geodynamic activity. Therefore the absence of significant Radon anomalies during or after the blast does not contradict assumptions, observations or conclusions as the occurrence of Radon anomalies prior or after an earthquake event due to associated long-term geodynamic processes.

  19. Effect of impact angle on vaporization

    Science.gov (United States)

    Schultz, Peter H.

    1996-09-01

    Impacts into easily vaporized targets such as dry ice and carbonates generate a rapidly expanding vapor cloud. Laboratory experiments performed in a tenuous atmosphere allow deriving the internal energy of this cloud through well-established and tested theoretical descriptions. A second set of experiments under near-vacuum conditions provides a second measure of energy as the internal energy converts to kinetic energy of expansion. The resulting data allow deriving the vaporized mass as a function of impact angle and velocity. Although peak shock pressures decrease with decreasing impact angle (referenced to horizontal), the amount of impact-generated vapor is found to increase and is derived from the upper surface. Moreover, the temperature of the vapor cloud appears to decrease with decreasing angle. These unexpected results are proposed to reflect the increasing roles of shear heating and downrange hypervelocity ricochet impacts created during oblique impacts. The shallow provenance, low temperature, and trajectory of such vapor have implications for larger-scale events, including enhancement of atmospheric and biospheric stress by oblique terrestrial impacts and impact recycling of the early atmosphere of Mars.

  20. Identification of relevant conditions and experiments for fuel-coolant interactions in nuclear power plants - SERENA Co-ordinated Programme (Steam Explosion Resolution for Nuclear Applications) Phase 1, Task 1 - Final report

    International Nuclear Information System (INIS)

    Magallon, D.; Scott de Martinville, E.; Chaumont, B.; Filippi, M.; Meignen, R.; Berthoud, G.; Ratel, G.; Melikhov, O.I.; Melikhov, V.I.; Jacobs, H.; Buerger, Manfred; Buck, Michael; Moriyama, K.; Nakamura, H.; Hirano, M.; Muramatsu, K.; Ishikawa, J.; Song, Jinho; Bang, Kwanghyun; Suh, Namduk; Sairanen, Risto; Lindholm, Ilona

    2004-01-01

    SERENA (Steam Explosion Resolution for Nuclear Applications) is an international OECD programme for the resolution of FCI remaining issues. The programme has origin the concerns expressed by the Senior Group Experts on Nuclear Safety Research and Programme (SESAR/FAP) about de-emphasis of FCI research all over the world, while uncertainties still exist on some aspects of FCI. After an evaluation of remaining needs by FCI experts in a meeting October 2000, a proposal was matured during 2001 following CSNI recommendations that existing knowledge should be carefully assessed before carrying out new experiments, and reactor application should be the focus of any new action. The work programme was approved by CSNI December 2001. The programme started January 2002. The overall objective of SERENA is to obtain convergence on the understanding of FCI processes and energetics, as well as on method(s) for reliable estimate of the magnitude of loadings for realistic reactor conditions, in order to bring understanding and predictability of FCI energetics to desirable levels for risk management. The work is performed in two phases: - Phase 1 analyses and evaluates knowledge and data on FCI by using available tools with the aim to identify areas where large uncertainties/ discrepancies still subsist and are important for predicting loads in reactors with a sufficient level of confidence, and work to be done, if any, to reduce these uncertainties/discrepancies. - Phase 2 will implement analytical and experimental actions to resolve these uncertainties/ discrepancies, if required. The objective of Phase 1 is reached through comparative calculations by available tools of existing experiments and reactor cases. It is divided into five tasks: 1. Identification of relevant conditions for FCI in reactor, 2. Comparison of various approaches for calculating jet break-up and pre-mixing, 3. Comparison of various approaches for calculating the explosion phase, 4. Reactor applications, 5

  1. Improvements to vapor generators

    International Nuclear Information System (INIS)

    Keller, Arthur; Monroe, Neil.

    1976-01-01

    A supporting system is proposed for vapor generators of the 'supported' type. Said supporting system is intended to compensate the disparities of thermal expansion due to the differences in the vertical dimensions of the tubes in the walls of the combustion chamber and their collectors compared to that of the balloon tanks and the connecting tube clusters of vaporization, the first one being longer than the second ones. Said system makes it possible to build said combustion chamber higher than the balloon tanks and the tube clusters of vaporization. The capacity of steam production is thus enhanced [fr

  2. Toward Improved Fidelity of Thermal Explosion Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, A L; Becker, R; Howard, W M; Wemhoff, A

    2009-07-17

    We will present results of an effort to improve the thermal/chemical/mechanical modeling of HMX based explosive like LX04 and LX10 for thermal cook-off. The original HMX model and analysis scheme were developed by Yoh et.al. for use in the ALE3D modeling framework. The current results were built to remedy the deficiencies of that original model. We concentrated our efforts in four areas. The first area was addition of porosity to the chemical material model framework in ALE3D that is used to model the HMX explosive formulation. This is needed to handle the roughly 2% porosity in solid explosives. The second area was the improvement of the HMX reaction network, which included the inclusion of a reactive phase change model base on work by Henson et.al. The third area required adding early decomposition gas species to the CHEETAH material database to develop more accurate equations of state for gaseous intermediates and products. Finally, it was necessary to improve the implicit mechanics module in ALE3D to more naturally handle the long time scales associated with thermal cook-off. The application of the resulting framework to the analysis of the Scaled Thermal Explosion (STEX) experiments will be discussed.

  3. Determining VCE damage zones using the GAME correlations and explosion regions

    NARCIS (Netherlands)

    Boot, H.; Voort, M.M. van der

    2013-01-01

    Predicting potential consequences of Vapor Cloud Explosions (VCEs) has always been an important issue in safety assessments, because of the devastating damage that this phenomenon can create on (petro chemical) production sites. Although the TNO Multi-Energy method has been recognized as one of the

  4. Environmental control for nuclear explosives

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, A W; Wells, W H [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-15

    Peaceful applications introduce some new environmental considerations into the design of nuclear explosives. Much of the experience gained in weapon work can be applied, but the requirement of survival in a very deep hole is not found in any military system. We will briefly mention the overall environment and make a few comparisons with some general characteristics of the weapon environment. The major portion of this paper is devoted to the special problems of pressure and temperature found in the emplacement environment. Potential users should know where we stand with regard to survival in hostile environments in terms of feasibility and possible effects on field operations. In all applications there are several things competing for the available diameter. Given that explosives can be made to work over a range of diameters and that necessary environmental control is feasible, all further discussions can be related to the cost of providing a hole big enough to accomplish the task. The items competing for diameter are: 1) bare nuclear assembly 2) insulation and cooling system if needed 3) pressure canister 4) shielding material 5) emplacement clearance All of these must be considered with the cost of the hole in optimizing an overall design. Conditions in a particular location will affect the shielding requirements and the emplacement clearance. The nuclear assembly can vary in size, but the long development time requires that decisions be made quite early, perhaps in ignorance of the economic details of a particular application. The pressure canister is a relatively straightforward design problem that can be resolved by giving appropriate consideration to all of the design requirements. In particular for 20,000 psi pressure in the emplacement hole, a canister of heat-treated alloy steel having a yield strength of 200,000 psi and a wall thickness which is about .07 times the outside diameter is adequate and straight- forward to fabricate. The insulation and cooling

  5. Explosive processes in nucleosynthesis

    International Nuclear Information System (INIS)

    Boyd, R.N.

    2002-01-01

    There are many explosive processes in nucleosynthesis: big bang nucleosynthesis, the rp-process, the γ-process, the ν-process, and the r-process. However, I will discuss just the rp-process and the r-process in detail, primarily because both seem to have been very active research areas of late, and because they have great potential for studies with radioactive nuclear beams. I will also discuss briefly the γ-process because of its inevitability in conjunction with the rp-process. (orig.)

  6. SLIFER measurement for explosive yield

    International Nuclear Information System (INIS)

    Bass, R.C.; Benjamin, B.C.; Miller, H.M.; Breding, D.R.

    1976-04-01

    This report describes the shorted location indicator by frequency of electrical resonance (SLIFER) system used at Sandia Laboratories for determination of explosive yield of under ground nuclear tests

  7. Zirconium hydride containing explosive composition

    Science.gov (United States)

    Walker, Franklin E.; Wasley, Richard J.

    1981-01-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a donor additive comprising a non-explosive compound or mixture of non-explosive compounds which when subjected to an energy fluence of 1000 calories/cm.sup.2 or less is capable of releasing free radicals each having a molecular weight between 1 and 120. Exemplary donor additives are dibasic acids, polyamines and metal hydrides.

  8. A strategy for the application of steam explosion codes to reactor analysis

    International Nuclear Information System (INIS)

    Moriyama, Kiyofumi; Nakamura, Hideo

    2006-01-01

    A technical view on the strategy for the application of steam explosion codes for plant scale analysis is described. It includes assumption of triggering at the time of peak premixed melt mass, tuning of the explosion model on typical alumina steam explosion data, consideration of void and solidification effects as primary mechanism to limit the premixed mass and explosion energetics, choice of simple heat partition models affecting evaporation. The view was developed through experiences in development, verification and application of a steam explosion simulation code, JASMINE, at Japan Atomic Energy Agency (JAEA), as well as participation in OECD SERENA Phase-1 program. (author)

  9. Simulation of steam explosion in stratified melt-coolant configuration

    International Nuclear Information System (INIS)

    Leskovar, Matjaž; Centrih, Vasilij; Uršič, Mitja

    2016-01-01

    Highlights: • Strong steam explosions may develop spontaneously in stratified configurations. • Considerable melt-coolant premixed layer formed in subcooled water with hot melts. • Analysis with MC3D code provided insight into stratified steam explosion phenomenon. • Up to 25% of poured melt was mixed with water and available for steam explosion. • Better instrumented experiments needed to determine dominant mixing process. - Abstract: A steam explosion is an energetic fuel coolant interaction process, which may occur during a severe reactor accident when the molten core comes into contact with the coolant water. In nuclear reactor safety analyses steam explosions are primarily considered in melt jet-coolant pool configurations where sufficiently deep coolant pool conditions provide complete jet breakup and efficient premixture formation. Stratified melt-coolant configurations, i.e. a molten melt layer below a coolant layer, were up to now believed as being unable to generate strong explosive interactions. Based on the hypothesis that there are no interfacial instabilities in a stratified configuration it was assumed that the amount of melt in the premixture is insufficient to produce strong explosions. However, the recently performed experiments in the PULiMS and SES (KTH, Sweden) facilities with oxidic corium simulants revealed that strong steam explosions may develop spontaneously also in stratified melt-coolant configurations, where with high temperature melts and subcooled water conditions a considerable melt-coolant premixed layer is formed. In the article, the performed study of steam explosions in a stratified melt-coolant configuration in PULiMS like conditions is presented. The goal of this analytical work is to supplement the experimental activities within the PULiMS research program by addressing the key questions, especially regarding the explosivity of the formed premixed layer and the mechanisms responsible for the melt-water mixing. To

  10. 76 FR 64974 - Commerce in Explosives; List of Explosive Materials (2011R-18T)

    Science.gov (United States)

    2011-10-19

    ... slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting powder. BTNEC [bis.... Esters of nitro-substituted alcohols. Ethyl-tetryl. Explosive conitrates. Explosive gelatins. Explosive... silver. Fulminating gold. Fulminating mercury. Fulminating platinum. Fulminating silver. G Gelatinized...

  11. 77 FR 58410 - Commerce in Explosives; List of Explosive Materials (2012R-10T)

    Science.gov (United States)

    2012-09-20

    ... sensitive slurry and water gel explosives. Blasting caps. Blasting gelatin. Blasting powder. BTNEC [bis.... Esters of nitro-substituted alcohols. Ethyl-tetryl. Explosive conitrates. Explosive gelatins. Explosive.... Fulminate of silver. Fulminating gold. Fulminating mercury. Fulminating platinum. Fulminating silver. G...

  12. Simulation of the chemical environment of a nuclear explosion with exploding wires

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Walter; Block, Oliver U.J. [Nuclear Engineering, Kansas State University, Manhattan, KS (United States)

    1970-05-15

    The chemical processes in an expanding underground cavity resulting from a nuclear explosion cannot be predicted or controlled as well as such physical characteristics as crater size, magnitude of the outgoing shock wave, or the extent of rock fracturing. However in most underground nuclear explosions it would be desirable to control the chemical and/or physical form and amount of radioactive fallout venting from the explosion. The high temperatures and corresponding high energy densities produced by exploding wires are sufficient to produce in the wire and material immediately surrounding it the temperature (a few thousand degrees) required to simulate the chemical environment of a nuclear explosion in the time interval just preceding the venting of the cavity. The economics and the size of exploding wire apparatus make this type of experiment readily applicable to laboratory study. Design of exploding wire circuits to obtain particular temperatures or energy densities can be completed using several different combinations of circuit and wire conditions. Since the circuit parameters, including charging voltage, capacitor bank capacitance and circuit inductance primarily determine the cost of the necessary laboratory equipment, these parameters should be selected by theoretical expressions while also considering economic factors. Wire parameters are then experimentally determined to produce the most energetic explosions with the selected circuit parameters. A theoretical method applicable to designing exploding wire circuits to produce the desired high temperatures and energy densities in the wire and surrounding sample material has been obtained. The method assumes that a thermal spike of energy is deposited in a low conductivity material (typical of the earth's crust) surrounding the wire. From the assumed temperature distribution in the surrounding sample material the energy which must be deposited in the thermal spike to produce the desired temperature and

  13. Gasoline Reid Vapor Pressure

    Science.gov (United States)

    EPA regulates the vapor pressure of gasoline sold at retail stations during the summer ozone season to reduce evaporative emissions from gasoline that contribute to ground-level ozone and diminish the effects of ozone-related health problems.

  14. The associated particle method explosives detection technology

    International Nuclear Information System (INIS)

    An Li; Chen Yuan; Guo Haiping; Zheng Pu; Wang Xinhua; He Tie; Mu Yunfeng; Yang Xiaofei; Zhu Chuanxin

    2009-01-01

    This article introduces the basic principle of associated alpha particles technique for explosives' inspection and the measurement system. The characteristic prompt gamma-rays come from water, graphite, liquid nitrogen, ammonium nitrate, melamine and simulated samples induced by D-T neutron from generator were gained by single alpha particles detector and gamma-ray detector. The complex gamma-ray spectra were deconvolved. The element ratio between the experiment and chemics molecular formula is agreement in 10%. (authors)

  15. Industry potential of large scale uses for peaceful nuclear explosives

    International Nuclear Information System (INIS)

    Russell, P.L.

    1969-01-01

    The industrial potential for peaceful uses of nuclear explosions entering a critical stage of development. Should Project Gasbuggy, an experiment to determine to what extent an underground nuclear explosion can stimulate the production of natural gas from low-permeability formations, prove a technical or economic success, a great step forward will have been made. Should other experiments now being considered in natural gas, oil shale, copper, coal, water resources, underground storage, and others, also demonstrate technical or economic advantage, it is conceivable to expect peaceful nuclear explosion to grow from our current rate of one or two experimental shots per year to hundreds of production explosions per year. This growth rate could be severely restricted or reduced to zero if public safety and environmental control cannot be exercised. (author)

  16. Industry potential of large scale uses for peaceful nuclear explosives

    Energy Technology Data Exchange (ETDEWEB)

    Russell, P L [Bureau of Mines, Denver, CO (United States)

    1969-07-01

    The industrial potential for peaceful uses of nuclear explosions entering a critical stage of development. Should Project Gasbuggy, an experiment to determine to what extent an underground nuclear explosion can stimulate the production of natural gas from low-permeability formations, prove a technical or economic success, a great step forward will have been made. Should other experiments now being considered in natural gas, oil shale, copper, coal, water resources, underground storage, and others, also demonstrate technical or economic advantage, it is conceivable to expect peaceful nuclear explosion to grow from our current rate of one or two experimental shots per year to hundreds of production explosions per year. This growth rate could be severely restricted or reduced to zero if public safety and environmental control cannot be exercised. (author)

  17. Numerical simulation on the explosive boiling phenomena on the surface of molten metal

    International Nuclear Information System (INIS)

    Chen Deqi; Peng Cheng; Wang Qinghua; Pan Liangming

    2014-01-01

    In this paper, numerical simulation was carried out to investigate the explosive boiling phenomenon on high temperature surface also the influence of vapor growth rate during explosive boiling, vapor condensation in sub-cooled water and the subsequent effect on flowing and heat transfer. The simulation result indicates that the steam on the molten metal surface grows with very high speed, and it pushes away the sub-cooled water around and causes severe flowing. The steam clusters which block the sub-cooled water to rewet the molten metal surface are appearing at the same time. During the growth, lifting off as well as condensation of the steam clusters, the sub-cooled water around is strongly disturbed, and obvious vortexes appear. Conversely, the vortex will influence the steam cluster detachment and cub-cooled water rewetting the metal surface. This simulation visually displays the complex explosive boiling phenomena on the molten metal surface with high temperature. (authors)

  18. Gas gun experiments and numerical simulations on the HMX-based explosive PBX 9501 in the overdriven 30 to 120 GPa pressure regime

    Science.gov (United States)

    Pittman, E. R.; Gustavsen, R. L.; Hagelberg, C. R.; Schmidt, J. H.

    2017-06-01

    The focus of this set of experiments is the development of data on the Hugoniot for the overdriven products equation of state (EOS) of PBX 9501 (95 weight % HMX, 5 weight % plastic binder) and to extend data from which current computational EOS models draw. This series of shots was conducted using the two-stage gas-guns at Los Alamos and aimed to gather data in the 30 to 120 GPa pressure regime. Experiments were simulated using FLAG, a Langrangian multiphysics code, using a one-dimensional setup which employs the Wescott Stewart Davis (WSD) reactive burn model. Prior to this study, data did not extend above 90 GPa, so the new data allowed the model to be re-evaluated. A comparison of the simulations with the experimental data shows that the model fits well below 80 GPa. However, the model did not fall within the error bars of the data for higher pressures. This is an indication that the PBX 9501 overdriven EOS products model could be modified to better match the data.

  19. Peaceful nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-07-01

    Article V of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) specifies that the potential benefits of peaceful applications of nuclear explosions be made available to non-nuclear weapon states party to the Treaty 'under appropriate international observation and through appropriate international procedures'. The International Atomic Energy Agency's responsibility and technical competence in this respect have been recognized by its Board of Governors, the Agency's General Conference and the United Nations' General Assembly. Since 1968 when the United Nations Conference of Non-Nuclear Weapon States also recommended that the Agency initiate the necessary studies in the peaceful nuclear explosions (PNE) field, the Agency has taken the following steps: 1. The exchange of scientific and technical information has been facilitated by circulating information on the status of the technology and through the Agency's International Nuclear Information System. A bibliography of PNE-related literature was published in 1970. 2. In 1972, guidelines for 'the international observation of PNE under the provisions of NPT and analogous provisions in other international agreements' were developed and approved by the Board of Governors. These guidelines defined the basic purpose of international observation as being to verify that in the course of conducting a PNE project the intent and letter of Articles I and II of the NPT are not violated. 3. In 1974, an advisory group developed 'Procedures for the Agency to Use in Responding to Requests for PNE-Related Services'. These procedures have also been approved by the Board of Governors. 4. The Agency has convened a series of technical meetings which reviewed the 'state-of-the- art'. These meetings were convened in 1970, 1971, 1972 and in January 1975. The Fourth Technical Committee was held in Vienna from 20-24 January 1975 under the chairmanship of Dr. Allen Wilson of Australia with Experts from: Australia, France, Federal

  20. Explosive compaction of aluminum oxide modified by multiwall carbon nanotubes

    Science.gov (United States)

    Buzyurkin, A. E.; Kraus, E. I.; Lukyanov, Ya L.

    2018-04-01

    This paper presents experiments and numerical research on explosive compaction of aluminum oxide powder modified by multiwall carbon nanotubes (MWCNT) and modeling of the stress state behind the shock front at shock loading. The aim of this study was to obtain a durable low-porosity compact sample. The explosive compaction technology is used in this problem because the aluminum oxide is an extremely hard and refractory material. Therefore, its compaction by traditional methods requires special equipment and considerable expenses.

  1. Introduction to High Explosives Science

    Energy Technology Data Exchange (ETDEWEB)

    Skidmore, Cary Bradford [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-17

    These are a set of slides for educational outreach to children on high explosives science. It gives an introduction to the elements involved in this science: carbon, hydrogen, nitrogen, and oxygen. Combined, these form the molecule HMX. Many pictures are also included to illustrate explosions.

  2. Steam explosion - physical foundations and relation to nuclear reactor safety

    International Nuclear Information System (INIS)

    Schumann, U.

    1982-08-01

    'Steam explosion' means the sudden evaporation of a fluid by heat exchange with a hotter material. Other terms are 'vapour explosion', 'thermal explosion', and 'energetic fuel-coolant interaction (FCI)'. In such an event a large fraction of the thermal energy initially stored in the hot material may possibly be converted into mechanical work. For pressurized water reactors one discusses (e.g. in risk analysis studies) a core melt-down accident during which molten fuel comes into contact with water. In the analysis of the consequences one has to investigate steam explosions. In this report an overview over the state of the knowledge is given. The overview is based on an extensive literature review. The objective of the report is to provide the basic knowledge which is required for understanding of the most important theories on the process of steam explosions. Following topics are treated: overview on steam explosion incidents, work potential, spontaneous nucleation, concept of detonation, results of some typical experiments, hydrodynamic fragmentation of drops, bubbles and jets, coarse mixtures, film-boiling, scenario of a core melt-down accident with possible steam-explosion in a pressurized water reactor. (orig.) [de

  3. Surface and body waves from surface and underground explosions

    International Nuclear Information System (INIS)

    Kusubov, A.S.

    1976-06-01

    The characteristics of surface and ground waves were recorded for surface and underground explosions up to 100 tons and 40 kt in magnitude, respectively, and a preliminary analysis of these results is presented. The experiments were conducted at NTS in the Yucca Flats, Nevada. Ground motions were detected with triaxial geophones along seismic lines extending up to 16 miles from the point of explosions. A comparison of Rayleigh waves generated by surface and underground explosions in the same lake bed is presented indicating a very different behavior of surface and ground waves from the two types of explosions. The magnitude of the transverse wave for surface shots was smaller by a factor of two than its longitudinal counterpart. The dependence of apparent periods on the blast energy was not apparent at a fixed distance from the explosions. Changes in the apparent period with distance for both types of explosion are compared indicating a strong layering effect of the lake bed. The ground motion study was complimented by excavation of cavities generated by the explosions

  4. New insights on entrainment and condensation in volcanic plumes: Constraints from independent observations of explosive eruptions and implications for assessing their impacts

    Science.gov (United States)

    Aubry, Thomas J.; Jellinek, A. Mark

    2018-05-01

    The turbulent entrainment of atmosphere and the condensation of water vapor govern the heights of explosive volcanic plumes. These processes thus determine the delivery and the lifetime of volcanic ash and aerosols into the atmosphere. Predictions of plume heights using one-dimensional "integral" models of volcanic plumes, however, suffer from very large uncertainties, related to parameterizations for entrainment and condensation. In particular, the wind entrainment coefficient β, which governs the contribution of crosswinds to turbulent entrainment, is subject to uncertainties of one order of magnitude, leading to relative uncertainties of the order of 50% on plume height. In this study, we use a database of 94 eruptive phases with independent estimates of mass eruption rate and plume height to constrain and evaluate four popular 1D models. We employ re-sampling methods to account for observational uncertainties. We show that plume height predictions are significantly improved when: i) the contribution of water vapor condensation to the plume buoyancy flux is excluded; and ii) the wind entrainment coefficient β is held constant between 0.1 and 0.4. We explore implications of these results for predicting the climate impacts of explosive eruptions and the likelihood that eruptions will form stable umbrella clouds or devastating pyroclastic flows. Last, we discuss the sensitivity of our results to the definition of plume height in the model in light of a recent set of laboratory experiments and draw conclusions for improving future databases of eruption parameters.

  5. A technique to depress desflurane vapor pressure.

    Science.gov (United States)

    Brosnan, Robert J; Pypendop, Bruno H

    2006-09-01

    To determine whether the vapor pressure of desflurane could be decreased by using a solvent to reduce the anesthetic molar fraction in a solution (Raoult's Law). We hypothesized that such an anesthetic mixture could produce anesthesia using a nonprecision vaporizer instead of an agent-specific, electronically controlled, temperature and pressure compensated vaporizer currently required for desflurane administration. One healthy adult female dog. Propylene glycol was used as a solvent for desflurane, and the physical characteristics of this mixture were evaluated at various molar concentrations and temperatures. Using a circle system with a breathing bag attached at the patient end and a mechanical ventilator to simulate respiration, an in-circuit, nonprecision vaporizer containing 40% desflurane and 60% propylene glycol achieved an 11.5% +/- 1.0% circuit desflurane concentration with a 5.2 +/- 0.4 (0 = off, 10 = maximum) vaporizer setting. This experiment was repeated with a dog attached to the breathing circuit under spontaneous ventilation with a fresh gas flow of 0.5 L minute(-1). Anesthesia was maintained for over 2 hours at a mean vaporizer setting of 6.2 +/- 0.4, yielding mean inspired and end-tidal desflurane concentrations of 8.7% +/- 0.5% and 7.9% +/- 0.7%, respectively. Rather than alter physical properties of vaporizers to suit a particular anesthetic agent, this study demonstrates that it is also possible to alter physical properties of anesthetic agents to suit a particular vaporizer. However, propylene glycol may not prove an ideal solvent for desflurane because of its instability in solution and substantial-positive deviation from Raoult's Law.

  6. Nuclear explosions and their effects

    Energy Technology Data Exchange (ETDEWEB)

    1958-01-01

    A brief historical background is given of the development of the atomic bomb. Also included is an account of the Hiroshima-Nagasaki bombing, plus some information on the testing and production of nuclear weapons by the United States, United Kingdom, and Russia. More detailed consideration is given to the following: the scientific principles of fission and fusion explosions; the energy released in fission and the radioactivity of fission products; blast, thermal, and radiologicalal effects of nuclear explosions; long-term radiological hazards from fall-out; and genetic effects of nuclear explosions. A brief account is given of the fission chain process, the concept of critical size, and the principles of implosion as applied to nuclear explosions. Limited information is presented on the controlled release of thermonuclear energy and catalyzed fusion reaction. Discussions are included on dose rates from radiation sources inside and outside the body, the effect of nuclear explosions on the weather, and the contamination of fish and marine organisms.

  7. Nucleosynthesis in stellar explosions

    Energy Technology Data Exchange (ETDEWEB)

    Woosley, S.E.; Axelrod, T.S.; Weaver, T.A.

    1983-01-01

    The final evolution and explosion of stars from 10 M/sub solar/ to 10/sup 6/ M/sub solar/ are reviewed with emphasis on factors affecting the expected nucleosynthesis. We order our paper in a sequence of decreasing mass. If, as many suspect, the stellar birth function was peaked towards larger masses at earlier times (see e.g., Silk 1977; but also see Palla, Salpeter, and Stahler 1983), this sequence of masses might also be regarded as a temporal sequence. At each stage of Galactic chemical evolution stars form from the ashes of preceding generations which typically had greater mass. A wide variety of Type I supernova models, most based upon accreting white dwarf stars, are also explored using the expected light curves, spectra, and nucleosynthesis as diagnostics. No clearly favored Type I model emerges that is capable of simultaneously satisfying all three constraints.

  8. Nucleosynthesis in stellar explosions

    International Nuclear Information System (INIS)

    Woosley, S.E.; Axelrod, T.S.; Weaver, T.A.

    1983-01-01

    The final evolution and explosion of stars from 10 M/sub solar/ to 10 6 M/sub solar/ are reviewed with emphasis on factors affecting the expected nucleosynthesis. We order our paper in a sequence of decreasing mass. If, as many suspect, the stellar birth function was peaked towards larger masses at earlier times (see e.g., Silk 1977; but also see Palla, Salpeter, and Stahler 1983), this sequence of masses might also be regarded as a temporal sequence. At each stage of Galactic chemical evolution stars form from the ashes of preceding generations which typically had greater mass. A wide variety of Type I supernova models, most based upon accreting white dwarf stars, are also explored using the expected light curves, spectra, and nucleosynthesis as diagnostics. No clearly favored Type I model emerges that is capable of simultaneously satisfying all three constraints

  9. Explosions of water clusters in intense laser fields

    International Nuclear Information System (INIS)

    Kumarappan, V.; Krishnamurthy, M.; Mathur, D.

    2003-01-01

    Energetic, highly charged oxygen ions O q+ (q≤6), are copiously produced upon laser field-induced disassembly of highly charged water clusters, (H 2 O) n and (D 2 O) n , n∼60, that are formed by seeding high-pressure helium or argon with water vapor. Ar n clusters (n∼40 000) formed under similar experimental conditions are found to undergo disassembly in the Coulomb explosion regime, with the energies of Ar q+ ions showing a q 2 dependence. Water clusters, which are argued to be considerably smaller in size, should also disassemble in the same regime, but the energies of fragment O q+ ions are found to depend linearly on q which, according to prevailing wisdom, ought to be a signature of hydrodynamic expansion that is expected of much larger clusters. The implication of these observations on our understanding of the two cluster explosion regimes, Coulomb explosion and hydrodynamic expansion, is discussed. Our results indicate that charge state dependences of ion energy do not constitute an unambiguous experimental signature of cluster explosion regime

  10. Comparative analysis of the vapor headspace of military-grade TNT versus NESTT TNT under dynamic and static conditions

    Science.gov (United States)

    Edge, Cindy C.; Gibb, Julie; Wasserzug, Louis S.

    1998-09-01

    The Institute for Biological Detection Systems (IBDS) has developed a quantitative vapor delivery system that can aid in characterizing dog's sensitivity and ability to recognize odor signatures for explosives and contraband substances. Determining of the dog's odor signature for detection of explosives is important because it may aid in eliminating the risk of handling explosives and reducing cross-contamination. Progress is being made in the development of training aids that represent the headspace of the explosives. NESTTTM TNT materials have been proposed as an approach to developing training aid simulates. In order for such aids to be effective they must mimic the headspace of the target material. This study evaluates the NESTTTM TNT product with regard to this criterion. NESTTTM TNT vapor was generated by the IBDS vapor delivery system, which incorporates a vapor generation cell that enables the user to control the conditions under which a substance is tested. The NESTTTM TNT vapor was compared to the headspace of military-grade TNT. The findings identify and quantify major vapor constituents of military-grade TNT and NESTTTM TNT. A comparative analysis evaluated the degree to which the NESTTTM TNT mimics the headspace of an actual TNT sample.

  11. Pre-shot simulations of far-field ground motion for the Source Physics Experiment (SPE) Explosions at the Climax Stock, Nevada National Security Site: SPE2

    Energy Technology Data Exchange (ETDEWEB)

    Mellors, R J; Rodgers, A; Walter, W; Ford, S; Xu, H; Matzel, E; Myers, S; Petersson, N A; Sjogreen, B; Hauk, T; Wagoner, J

    2011-10-18

    The Source Physics Experiment (SPE) is planning a 1000 kg (TNT equivalent) shot (SPE2) at the Nevada National Security Site (NNSS) in a granite borehole at a depth (canister centroid) of 45 meters. This shot follows an earlier shot of 100 kg in the same borehole at a depth 60 m. Surrounding the shotpoint is an extensive array of seismic sensors arrayed in 5 radial lines extending out 2 km to the north and east and approximately 10-15 to the south and west. Prior to SPE1, simulations using a finite difference code and a 3D numerical model based on the geologic setting were conducted, which predicted higher amplitudes to the south and east in the alluvium of Yucca Flat along with significant energy on the transverse components caused by scattering within the 3D volume along with some contribution by topographic scattering. Observations from the SPE1 shot largely confirmed these predictions although the ratio of transverse energy relative to the vertical and radial components was in general larger than predicted. A new set of simulations has been conducted for the upcoming SPE2 shot. These include improvements to the velocity model based on SPE1 observations as well as new capabilities added to the simulation code. The most significant is the addition of a new source model within the finite difference code by using the predicted ground velocities from a hydrodynamic code (GEODYN) as driving condition on the boundaries of a cube embedded within WPP which provides a more sophisticated source modeling capability linked directly to source site materials (e.g. granite) and type and size of source. Two sets of SPE2 simulations are conducted, one with a GEODYN source and 3D complex media (no topography node spacing of 5 m) and one with a standard isotropic pre-defined time function (3D complex media with topography, node spacing of 5 m). Results were provided as time series at specific points corresponding to sensor locations for both translational (x,y,z) and rotational

  12. MC3D modelling of stratified explosion

    International Nuclear Information System (INIS)

    Picchi, S.; Berthoud, G.

    1999-01-01

    It is known that a steam explosion can occur in a stratified geometry and that the observed yields are lower than in the case of explosion in a premixture configuration. However, very few models are available to quantify the amount of melt which can be involved and the pressure peak that can be developed. In the stratified application of the MC3D code, mixing and fragmentation of the melt are explained by the growth of Kelvin Helmholtz instabilities due to the shear flow of the two phase coolant above the melt. Such a model is then used to recalculate the Frost-Ciccarelli tin-water experiment. Pressure peak, speed of propagation, bubble shape and erosion height are well reproduced as well as the influence of the inertial constraint (height of the water pool). (author)

  13. Effects of frustration on explosive synchronization

    Science.gov (United States)

    Huang, Xia; Gao, Jian; Sun, Yu-Ting; Zheng, Zhi-Gang; Xu, Can

    2016-12-01

    In this study, we consider the emergence of explosive synchronization in scale-free networks by considering the Kuramoto model of coupled phase oscillators. The natural frequencies of oscillators are assumed to be correlated with their degrees and frustration is included in the system. This assumption can enhance or delay the explosive transition to synchronization. Interestingly, a de-synchronization phenomenon occurs and the type of phase transition is also changed. Furthermore, we provide an analytical treatment based on a star graph, which resembles that obtained in scale-free networks. Finally, a self-consistent approach is implemented to study the de-synchronization regime. Our findings have important implications for controlling synchronization in complex networks because frustration is a controllable parameter in experiments and a discontinuous abrupt phase transition is always dangerous in engineering in the real world.

  14. MC3D modelling of stratified explosion

    Energy Technology Data Exchange (ETDEWEB)

    Picchi, S.; Berthoud, G. [DTP/SMTH/LM2, CEA, 38 - Grenoble (France)

    1999-07-01

    It is known that a steam explosion can occur in a stratified geometry and that the observed yields are lower than in the case of explosion in a premixture configuration. However, very few models are available to quantify the amount of melt which can be involved and the pressure peak that can be developed. In the stratified application of the MC3D code, mixing and fragmentation of the melt are explained by the growth of Kelvin Helmholtz instabilities due to the shear flow of the two phase coolant above the melt. Such a model is then used to recalculate the Frost-Ciccarelli tin-water experiment. Pressure peak, speed of propagation, bubble shape and erosion height are well reproduced as well as the influence of the inertial constraint (height of the water pool). (author)

  15. Development of Non-hazardous Explosives for Security Training and Testing (NESTT)

    International Nuclear Information System (INIS)

    Kury, J.W.; Simpson, R.L.; Hallowell, S.F.

    1996-01-01

    The security force at the Lawrence Livermore National Laboratory (LLNL) routinely used canines to search for explosives and other contraband substances. The use of threat quantities of explosive for realistic training in populated or sensitive Laboratory areas has not been permitted because of the hazard. To overcome this limitation a series of non-hazardous materials with authentic signatures have been prepared and evaluated. A series of materials has been prepared that have authentic properties of explosives but are non-hazardous. These NESTT materials are prepared by coating a few micron thick layer of an explosive on a non-reactive substrate. This produces a formulation with an authentic vapor and molecular signature. Authentic x-ray and oxygen/nitrogen density signatures are obtained through the appropriate choice of a substrate. The signatures of NESTT TNT and NESTT Comp. C-4 have been verified by instrument and canine (K-9) detection in a Beta Test Program

  16. Vapor pressures and enthalpies of vaporization of azides

    International Nuclear Information System (INIS)

    Verevkin, Sergey P.; Emel'yanenko, Vladimir N.; Algarra, Manuel; Manuel Lopez-Romero, J.; Aguiar, Fabio; Enrique Rodriguez-Borges, J.; Esteves da Silva, Joaquim C.G.

    2011-01-01

    Highlights: → We prepared and measured vapor pressures and vaporization enthalpies of 7 azides. → We examined consistency of new and available in the literature data. → Data for geminal azides and azido-alkanes selected for thermochemical calculations. - Abstract: Vapor pressures of some azides have been determined by the transpiration method. The molar enthalpies of vaporization Δ l g H m of these compounds were derived from the temperature dependencies of vapor pressures. The measured data sets were successfully checked for internal consistency by comparison with vaporization enthalpies of similarly structured compounds.

  17. Numerical modelling of multiphase liquid-vapor-gas flows with interfaces and cavitation

    Science.gov (United States)

    Pelanti, Marica

    2017-11-01

    We are interested in the simulation of multiphase flows where the dynamical appearance of vapor cavities and evaporation fronts in a liquid is coupled to the dynamics of a third non-condensable gaseous phase. We describe these flows by a single-velocity three-phase compressible flow model composed of the phasic mass and total energy equations, the volume fraction equations, and the mixture momentum equation. The model includes stiff mechanical and thermal relaxation source terms for all the phases, and chemical relaxation terms to describe mass transfer between the liquid and vapor phases of the species that may undergo transition. The flow equations are solved by a mixture-energy-consistent finite volume wave propagation scheme, combined with simple and robust procedures for the treatment of the stiff relaxation terms. An analytical study of the characteristic wave speeds of the hierarchy of relaxed models associated to the parent model system is also presented. We show several numerical experiments, including two-dimensional simulations of underwater explosive phenomena where highly pressurized gases trigger cavitation processes close to a rigid surface or to a free surface. This work was supported by the French Government Grant DGA N. 2012.60.0011.00.470.75.01, and partially by the Norwegian Grant RCN N. 234126/E30.

  18. CTBT calibration explosions at the Semipalatinsk test site (1997-2000)

    International Nuclear Information System (INIS)

    Leith, W.; Kluchko, L.J.; Knowles, C.P.; Linger, D.A.; Gabriel, L.; Belyashova, N.N.; Tukhvatulin, Sh.T.; Demin, V.N.; Konovalov, V.E.

    2000-01-01

    The article shows the results of experiments, conducted together by American and Kazakhstan researchers at the Semipalatinsk test site during 6 chemical calibration explosions and preparation of the seventh between 1997 and 2000. The main goal of the experiments is calibration of International Monitoring System for Comprehensive Test Ban Treaty and development of understanding of explosions as seismic sources. (author)

  19. Molecular dynamics study of the vaporization of an ionic drop.

    Science.gov (United States)

    Galamba, N

    2010-09-28

    The melting of a microcrystal in vacuum and subsequent vaporization of a drop of NaCl were studied through molecular dynamics simulations with the Born-Mayer-Huggins-Tosi-Fumi rigid-ion effective potential. The vaporization was studied for a single isochor at increasing temperatures until the drop completely vaporized, and gaseous NaCl formed. Examination of the vapor composition shows that the vapor of the ionic drop and gaseous NaCl are composed of neutral species, the most abundant of which, ranging from simple NaCl monomers (ion pairs) to nonlinear polymers, (Na(n)Cl(n))(n=2-4). The enthalpies of sublimation, vaporization, and dissociation of the different vapor species are found to be in reasonable agreement with available experimental data. The decrease of the enthalpy of vaporization of the vapor species, with the radius of the drop decrease, accounts for a larger fraction of trimers and tetramers than that inferred from experiments. Further, the rhombic dimer is significantly more abundant than its linear isomer although the latter increases with the temperature. The present results suggest that both trimers and linear dimers may be important to explain the vapor pressure of molten NaCl at temperatures above 1500 K.

  20. Molecular dynamics study of the vaporization of an ionic drop

    Science.gov (United States)

    Galamba, N.

    2010-09-01

    The melting of a microcrystal in vacuum and subsequent vaporization of a drop of NaCl were studied through molecular dynamics simulations with the Born-Mayer-Huggins-Tosi-Fumi rigid-ion effective potential. The vaporization was studied for a single isochor at increasing temperatures until the drop completely vaporized, and gaseous NaCl formed. Examination of the vapor composition shows that the vapor of the ionic drop and gaseous NaCl are composed of neutral species, the most abundant of which, ranging from simple NaCl monomers (ion pairs) to nonlinear polymers, (NanCln)n=2-4. The enthalpies of sublimation, vaporization, and dissociation of the different vapor species are found to be in reasonable agreement with available experimental data. The decrease of the enthalpy of vaporization of the vapor species, with the radius of the drop decrease, accounts for a larger fraction of trimers and tetramers than that inferred from experiments. Further, the rhombic dimer is significantly more abundant than its linear isomer although the latter increases with the temperature. The present results suggest that both trimers and linear dimers may be important to explain the vapor pressure of molten NaCl at temperatures above 1500 K.

  1. Mechanical efficiency of the energy release during a steam explosion

    International Nuclear Information System (INIS)

    Krieg, R.

    1997-01-01

    The mechanical processes during the expansion phase of a steam explosion with intimately fragmented liquid particles is investigated based on elementary principles and analytical solutions. During a short load pulse, the different densities of the water and the melted particles lead to different velocities. After the load pulse, viscosity effects lead to a slow down of the higher velocities and to a corresponding reconversion of the kinetic energy of the mixture into thermal energy. It is shown that both effects are proportional to each other. The ratio between the residual and the applied mechanical energy is defined as the mechanical efficiency of the steam explosion. Using data typical for a steam explosion in a pressurized water reactor, mechanical efficiencies of <50% are estimated. Considering that the thermodynamic efficiencies are quite limited, the very low conversion rates from thermal energy into mechanical energy observed during steam explosion experiments can be more easily understood

  2. Raman hyperspectral imaging in conjunction with independent component analysis as a forensic tool for explosive analysis: The case of an ATM explosion.

    Science.gov (United States)

    Almeida, Mariana Ramos; Logrado, Lucio Paulo Lima; Zacca, Jorge Jardim; Correa, Deleon Nascimento; Poppi, Ronei Jesus

    2017-11-01

    In this work, Raman hyperspectral imaging, in conjunction with independent component analysis, was employed as an analytical methodology to detect an ammonium nitrate fuel oil (ANFO) explosive in banknotes after an ATM explosion experiment. The proposed methodology allows for the identification of the ANFO explosive without sample preparation or destroying the sample, at quantities as small as 70μgcm -2 . The explosive was identified following ICA data decomposition by the characteristic nitrate band at 1044cm -1 . The use of Raman hyperspectral imaging and independent component analysis shows great potential for identifying forensic samples by providing chemical and spatial information. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Shock-induced explosive chemistry in a deterministic sample configuration.

    Energy Technology Data Exchange (ETDEWEB)

    Stuecker, John Nicholas; Castaneda, Jaime N.; Cesarano, Joseph, III (,; ); Trott, Wayne Merle; Baer, Melvin R.; Tappan, Alexander Smith

    2005-10-01

    Explosive initiation and energy release have been studied in two sample geometries designed to minimize stochastic behavior in shock-loading experiments. These sample concepts include a design with explosive material occupying the hole locations of a close-packed bed of inert spheres and a design that utilizes infiltration of a liquid explosive into a well-defined inert matrix. Wave profiles transmitted by these samples in gas-gun impact experiments have been characterized by both velocity interferometry diagnostics and three-dimensional numerical simulations. Highly organized wave structures associated with the characteristic length scales of the deterministic samples have been observed. Initiation and reaction growth in an inert matrix filled with sensitized nitromethane (a homogeneous explosive material) result in wave profiles similar to those observed with heterogeneous explosives. Comparison of experimental and numerical results indicates that energetic material studies in deterministic sample geometries can provide an important new tool for validation of models of energy release in numerical simulations of explosive initiation and performance.

  4. Peaceful applications of nuclear explosions

    International Nuclear Information System (INIS)

    Wallin, L.B.

    1975-12-01

    The intension of this report is to give a survey of the field of peaceful applications of nuclear explosions. As an introduction some examples of possibilities of application are given together with a simple description of nuclear explosions under ground. After a summary of what has been done and will be done in this field nationally and internationally, a short discussion of advantages and problems with peaceful application of nuclear explosions follows. The risks of spreading nuclear weapons due to this applications are also touched before the report is finished with an attempt to judge the future development in this field. (M.S.)

  5. Donor free radical explosive composition

    Science.gov (United States)

    Walker, Franklin E. [15 Way Points Rd., Danville, CA 94526; Wasley, Richard J. [4290 Colgate Way, Livermore, CA 94550

    1980-04-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a donor additive comprising an organic compound or mixture of organic compounds capable of releasing low molecular weight free radicals or ions under mechanical or electrical shock conditions and which is not an explosive, or an inorganic compound or mixture of inorganic compounds capable of releasing low molecular weight free radicals or ions under mechanical or electrical shock conditions and selected from ammonium or alkali metal persulfates.

  6. Explosive coalescence of Magnetic Islands

    International Nuclear Information System (INIS)

    Tajima, T.; Sakai, J.I.

    1985-04-01

    An explosive reconnection process associated with nonlinear evolution of the coalescence instability is found through studies of particle and magnetohydrodynamic simulations. The explosive coalescence is a self-similar process of magnetic collapse, in which the magnetic and electrostatic energies and temperatures explode toward the explosion time t 0 as (t 0 -t)/sup 8/3/,(t 0 -t) -4 , and (t 0 -t)/sup -8/3/, respectively. Ensuing amplitude oscillations in these quantities are identified by deriving an equation of motion for the scale factor in the Sagdeev potential

  7. DSMC simulations of vapor transport toward development of the lithium vapor box divertor concept

    Science.gov (United States)

    Jagoe, Christopher; Schwartz, Jacob; Goldston, Robert

    2016-10-01

    The lithium vapor divertor box concept attempts to achieve volumetric dissipation of the high heat efflux from a fusion power system. The vapor extracts the heat of the incoming plasma by ionization and radiation, while remaining localized in the vapor box due to differential pumping based on rapid condensation. Preliminary calculations with lithium vapor at densities appropriate for an NSTX-U-scale machine give Knudsen numbers between 0.01 and 1, outside both the range of continuum fluid dynamics and of collisionless Monte Carlo. The direct-simulation Monte Carlo (DSMC) method, however, can simulate rarefied gas flows in this regime. Using the solver contained in the OpenFOAM package, pressure-driven flows of water vapor will be analyzed. The use of water vapor in the relevant range of Knudsen number allows for a flexible similarity experiment to verify the reliability of the code before moving to tests with lithium. The simulation geometry consists of chains of boxes on a temperature gradient, connected by slots with widths that are a representative fraction of the dimensions of the box. We expect choked flow, sonic shocks, and order-of-magnitude pressure and density drops from box to box, but this expectation will be tested in the simulation and then experiment. This work is supported by the Princeton Environmental Institute.

  8. Cavity pressure history of contained nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Chapin, C E [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-01

    Knowledge of pressure in cavities created by contained nuclear explosions is useful for estimating the possibility of venting radioactive debris to the atmosphere. Measurements of cavity pressure, or temperature, would be helpful in evaluating the correctness of present code predictions of underground explosions. In instrumenting and interpreting such measurements it is necessary to have good theoretical estimates of cavity pressures. In this paper cavity pressure is estimated at the time when cavity growth is complete. Its subsequent decrease due to heat loss from the cavity to the surrounding media is also predicted. The starting pressure (the pressure at the end of cavity growth) is obtained by adiabatic expansion to the final cavity size of the vaporized rock gas sphere created by the explosion. Estimates of cavity size can be obtained by stress propagation computer codes, such as SOC and TENSOR. However, such estimates require considerable time and effort. In this paper, cavity size is estimated using a scheme involving simple hand calculations. The prediction is complicated by uncertainties in the knowledge of silica water system chemistry and a lack of information concerning possible blowoff of wall material during cavity growth. If wall material blows off, it can significantly change the water content in the cavity, compared to the water content in the ambient media. After cavity growth is complete, the pressure will change because of heat loss to the surrounding media. Heat transfer by convection, radiation and conduction is considered, and its effect on the pressure is calculated. Analysis of cavity heat transfer is made difficult by the complex nature of processes which occur at the wall where melting, vaporization and condensation of the gaseous rock can all occur. Furthermore, the melted wall material could be removed by flowing or dripping to the cavity floor. It could also be removed by expansion of the steam contained in the melt (blowoff) and by

  9. Numerical schemes for explosion hazards

    International Nuclear Information System (INIS)

    Therme, Nicolas

    2015-01-01

    In nuclear facilities, internal or external explosions can cause confinement breaches and radioactive materials release in the environment. Hence, modeling such phenomena is crucial for safety matters. Blast waves resulting from explosions are modeled by the system of Euler equations for compressible flows, whereas Navier-Stokes equations with reactive source terms and level set techniques are used to simulate the propagation of flame front during the deflagration phase. The purpose of this thesis is to contribute to the creation of efficient numerical schemes to solve these complex models. The work presented here focuses on two major aspects: first, the development of consistent schemes for the Euler equations, then the buildup of reliable schemes for the front propagation. In both cases, explicit in time schemes are used, but we also introduce a pressure correction scheme for the Euler equations. Staggered discretization is used in space. It is based on the internal energy formulation of the Euler system, which insures its positivity and avoids tedious discretization of the total energy over staggered grids. A discrete kinetic energy balance is derived from the scheme and a source term is added in the discrete internal energy balance equation to preserve the exact total energy balance at the limit. High order methods of MUSCL type are used in the discrete convective operators, based solely on material velocity. They lead to positivity of density and internal energy under CFL conditions. This ensures that the total energy cannot grow and we can furthermore derive a discrete entropy inequality. Under stability assumptions of the discrete L8 and BV norms of the scheme's solutions one can prove that a sequence of converging discrete solutions necessarily converges towards the weak solution of the Euler system. Besides it satisfies a weak entropy inequality at the limit. Concerning the front propagation, we transform the flame front evolution equation (the so called

  10. Explosive actuated valve

    International Nuclear Information System (INIS)

    Byrne, K.G.

    1983-01-01

    1. A device of the character described comprising the combination of a housing having an elongate bore and including a shoulder extending inwardly into said bore, a single elongate movable plunger disposed in said bore including an outwardly extending flange adjacent one end thereof overlying said shoulder, normally open conduit means having an inlet and an outlet perpendicularly piercing said housing intermediate said shoulder and said flange and including an intermediate portion intersecting and normally openly communicating with said bore at said shoulder, normally closed conduit means piercing said housing and intersecting said bore at a location spaced from said normally open conduit means, said elongate plunger including a shearing edge adjacent the other end thereof normally disposed intermediate both of said conduit means and overlying a portion of said normally closed conduit means, a deformable member carried by said plunger intermediate said flange and said shoulder and normally spaced from and overlying the intermediate portion of said normally open conduit means, and means on the housing communicating with the bore to retain an explosive actuator for moving said plunger to force the deformable member against the shoulder and extrude a portion of the deformable member out of said bore into portions of the normally open conduit means for plugging the same and to effect the opening of said normally closed conduit means by the plunger shearing edge substantially concomitantly with the plugging of the normally open conduit means

  11. Furball Explosive Breakout Test

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Joshua David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-05

    For more than 30 years the Onionskin test has been the primary way to study the surface breakout of a detonation wave. Currently the Onionskin test allows for only a small, one dimensional, slice of the explosive in question to be observed. Asymmetrical features are not observable with the Onionskin test and its one dimensional view. As a result, in 2011, preliminary designs for the Hairball and Furball were developed then tested. The Hairball used shorting pins connected to an oscilloscope to determine the arrival time at 24 discrete points. This limited number of data points, caused by the limited number of oscilloscope channels, ultimately led to the Hairball’s demise. Following this, the Furball was developed to increase the number of data points collected. Instead of shorting pins the Furball uses fiber optics imaged by a streak camera to determine the detonation wave arrival time for each point. The original design was able to capture the detonation wave’s arrival time at 205 discrete points with the ability to increase the number of data points if necessary.

  12. Vaporization of irradiated droplets

    International Nuclear Information System (INIS)

    Armstrong, R.L.; O'Rourke, P.J.; Zardecki, A.

    1986-01-01

    The vaporization of a spherically symmetric liquid droplet subject to a high-intensity laser flux is investigated on the basis of a hydrodynamic description of the system composed of the vapor and ambient gas. In the limit of the convective vaporization, the boundary conditions at the fluid--gas interface are formulated by using the notion of a Knudsen layer in which translational equilibrium is established. This leads to approximate jump conditions at the interface. For homogeneous energy deposition, the hydrodynamic equations are solved numerically with the aid of the CON1D computer code (''CON1D: A computer program for calculating spherically symmetric droplet combustion,'' Los Alamos National Laboratory Report No. LA-10269-MS, December, 1984), based on the implict continuous--fluid Eulerian (ICE) [J. Comput. Phys. 8, 197 (1971)] and arbitrary Lagrangian--Eulerian (ALE) [J. Comput. Phys. 14, 1227 (1974)] numerical mehtods. The solutions exhibit the existence of two shock waves propagating in opposite directions with respect to the contact discontinuity surface that separates the ambient gas and vapor

  13. Heat of vaporization spectrometer

    International Nuclear Information System (INIS)

    Edwards, D. Jr.

    1978-01-01

    Multilayer desorption measurements of various substances adsorbed on a stainless steel substrate are found to exhibit desorption profiles consistent with a zeroth order desorption model. The singleness of the desorption transients together with their narrow peak widths makes the technique ideally suited for a heat of vaporization spectrometer for either substance analysis or identification

  14. Natural gas production from underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    1965-01-01

    A remote location in Rio Arriba County, NW. New Mexico, is being considered as the site for an experiment in the use of a nuclear explosive to increase production from a natural gas field. A feasibility study has been conducted by the El Paso Natural Gas Co., the U.S. Atomic Energy commission, and the U.S. Bureau of Mines. As presently conceived, a nuclear explosive would be set in an emplacement hole and detonated. The explosion would create a cylinder or ''chimney'' of collapsed rock, and a network of fractures extending beyond the chimney. The fractures are the key effect. These would consist of new fractures, enlargement of existing ones, and movement along planes where strata overlap. In addition, there are a number of intangible but important benefits that could accrue from the stimulating effect. Among these are the great increase in recoverable reserves and the deliverability of large volumes of gas during the periods of high demand. It is believed that this type of well stimulation may increase the total gas production of these low permeability natural gas fields by about 7 times the amounts now attainable.

  15. Development of steam explosion simulation code JASMINE

    Energy Technology Data Exchange (ETDEWEB)

    Moriyama, Kiyofumi; Yamano, Norihiro; Maruyama, Yu; Kudo, Tamotsu; Sugimoto, Jun [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Nagano, Katsuhiro; Araki, Kazuhiro

    1995-11-01

    A steam explosion is considered as a phenomenon which possibly threatens the integrity of the containment vessel of a nuclear power plant in a severe accident condition. A numerical calculation code JASMINE (JAeri Simulator for Multiphase INteraction and Explosion) purposed to simulate the whole process of steam explosions has been developed. The premixing model is based on a multiphase flow simulation code MISTRAL by Fuji Research Institute Co. In JASMINE code, the constitutive equations and the flow regime map are modified for the simulation of premixing related phenomena. The numerical solution method of the original code is succeeded, i.e. the basic equations are discretized semi-implicitly, BCGSTAB method is used for the matrix solver to improve the stability and convergence, also TVD scheme is applied to capture a steep phase distribution accurately. Test calculations have been performed for the conditions correspond to the experiments by Gilbertson et al. and Angelini et al. in which mixing of solid particles and water were observed in iso-thermal condition and with boiling, respectively. (author).

  16. Optical pyrometry of fireballs of metalized explosives

    Energy Technology Data Exchange (ETDEWEB)

    Goroshin, Samuel; Frost, David L.; Levine, Jeffrey [McGill University, Mechanical Engineering, 817 Sherbrooke St. W., Montreal, Quebec, H3A 2K6 (Canada); Yoshinaka, Akio; Zhang, Fan [Defence R and D Canada - Suffield, Box 4000, Stn. Main, Medicine Hat, Alberta, T1A 8K6 (Canada)

    2006-06-15

    Fast-response optical diagnostics (a time-integrated spectrometer and two separate fast-response three-color pyrometers) are used to record the transient visible radiation emitted by a fireball produced when a condensed explosive is detonated. Measurement of the radiant intensity, in several narrow wavelength bands, is used to estimate the temperature of the condensed products within the fireball. For kg-scale conventional oxygen-deficient homogeneous TNT and nitromethane explosive charges, the radiant intensity reaches a maximum typically after tens of milliseconds, but the measured fireball temperature remains largely constant for more than 100 ms, at a value of about 2,000 K, consistent with predictions using equilibrium thermodynamics codes. When combustible metal particles (aluminum, magnesium or zirconium) are added to the explosive, reaction of the particles enhances the radiant energy and the fireball temperature is increased. In this case the fireball temperatures are lower than equilibrium predictions, but are consistent with measurements of particle temperature in single particle ignition experiments. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  17. Development of steam explosion simulation code JASMINE

    International Nuclear Information System (INIS)

    Moriyama, Kiyofumi; Yamano, Norihiro; Maruyama, Yu; Kudo, Tamotsu; Sugimoto, Jun; Nagano, Katsuhiro; Araki, Kazuhiro.

    1995-11-01

    A steam explosion is considered as a phenomenon which possibly threatens the integrity of the containment vessel of a nuclear power plant in a severe accident condition. A numerical calculation code JASMINE (JAeri Simulator for Multiphase INteraction and Explosion) purposed to simulate the whole process of steam explosions has been developed. The premixing model is based on a multiphase flow simulation code MISTRAL by Fuji Research Institute Co. In JASMINE code, the constitutive equations and the flow regime map are modified for the simulation of premixing related phenomena. The numerical solution method of the original code is succeeded, i.e. the basic equations are discretized semi-implicitly, BCGSTAB method is used for the matrix solver to improve the stability and convergence, also TVD scheme is applied to capture a steep phase distribution accurately. Test calculations have been performed for the conditions correspond to the experiments by Gilbertson et al. and Angelini et al. in which mixing of solid particles and water were observed in iso-thermal condition and with boiling, respectively. (author)

  18. Thermal hazard assessment of AN and AN-based explosives

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, T.; Lightfoot, P. D.; Fouchard, R.; Jones, D. E. G. [Natural Resources Canada, CANMET Canadian Explosives Research Laboratory, Ottawa, ON (Canada)

    2002-12-01

    Ammonium-based aqeous solutions of various concentrations are processed in both the fertilizer and explosives industry, and ammonium nitrate emulsions form the basis of bulk ammonium nitrate emulsion explosives. Major accidents involving overheating of large quantities of these products are not uncommon. To provide guidance to handling large bulk quantities of these materials laboratory experiments must be carried out in such a way as to minimize heat losses from the samples. In this study experiments were performed on pure ammonium, the popular commercial explosive ANFO, various aqueous ammonium solutions and typical bulk and packaged ammonium nitrate emulsions, using two laboratory-scale calorimeters (accelerating rate calorimeter and adiabatic Dewar calorimeter). The objective of the experiments was to study the effects of sample mass, atmosphere, and formulation on the resulting onset temperatures. Result from the two techniques were compared and a method for extrapolating these results to large-scale inventories was proposed. 22 refs., 4 tabs., 14 figs.

  19. Enthalpy of Vaporization and Vapor Pressures: An Inexpensive Apparatus

    Science.gov (United States)

    Battino, Rubin; Dolson, David A.; Hall, Michael A.; Letcher, Trevor M.

    2007-01-01

    A simple and inexpensive method to determine the enthalpy of vaporization of liquids by measuring vapor pressure as a function of temperature is described. The vapor pressures measured with the stopcock cell were higher than the literature values and those measured with the sidearm rubber septum cell were both higher and lower than literature…

  20. Water-bearing explosive compositions

    Energy Technology Data Exchange (ETDEWEB)

    Gay, G M

    1970-12-21

    An explosive water-bearing composition, with high detonation velocity, comprises a mixture of (1) an inorganic oxidizer salt; (2) nitroglycerine; (3) nitrocellulose; (4) water; and (5) a water thickening agent. (11 claims)

  1. Studies on micro-structures at vapor-liquid interfaces of film boiling on hot liquid surface at arriving of a shock pressure

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Akira; Lee, S. [Tokyo Inst. of Tech. (Japan)

    1998-01-01

    In vapor explosions, a pressure wave (shock wave) plays a fundamental role in the generation, propagation and escalation of the explosion. Transient volume change by rapid heat flow from a high temperature liquid to a low temperature volatile one and phase change generate micro-scale flow and the pressure wave. One of key issues for the vapor explosion is to make clear the mechanism to support the explosive energy release from hot drop to cold liquid. According to our observations by an Image Converter Camera, growth rate of vapor film around a hot tin drop became several times higher than that around a hot Platinum tube at the same conditions when a pressure pulse collapsed the film. The thermally induced fragmentation was followed by the explosive growth rate of the hot drop. In the previous report, we have proposed that the interface instability and fragmentation model in which the fine Taylor instability of vapor-liquid interface at the collapsing and re-growth phase of vapor film and the instability induced by the high pressure spots at the drop surface were assumed. In this study, the behavior of the vapor-liquid interface region at arrival of a pressure pulse was investigated by the CIPRIS code which is able to simulate dynamics of transient multi-phase interface regions. It is compared with the observation results. Through detailed investigations of these results, the mechanisms of the thermal fragmentation of single drop are discussed. (J.P.N.)

  2. PWFA plasma source - interferometric diagnostics for Li vapor density measurements

    International Nuclear Information System (INIS)

    Sivakumaran, V.; Mohandas, K.K.; Singh, Sneha; Ravi Kumar, A.V.

    2015-01-01

    A prototype (40 cm long) plasma source based on Li heat pipe oven has been developed for the Plasma Wakefield Acceleration (PWFA) experiments at IPR (IPR), Gujarat as a part of the ongoing Accelerator Programme. Li vapor in the oven is produced by heating solid Li in helium buffer gas. A uniform column of Li plasma is generated by UV photo ionization (193 nm) of the Li vapor in the heat pipe oven. In these experiments, an accurate measurement of Li vapor density is important as it has got a direct consequence on the plasma electron density. In the present experiment, the vapor density is measured optically by using Hook method (spectrally resolved white light interferometry). The hook like structure formed near the vicinity of the Li 670.8 nm resonance line was recorded with a white light Mach Zehnder interferometer crossed with an imaging spectrograph to estimate the Li vapor density. The vapor density measurements have been carried out as a function of external oven temperature and the He buffer gas pressure. This technique has the advantage of being insensitive to line broadening and line shape, and its high dynamic range even with optically thick absorption line. Here, we present the line integrated Lithium vapor density measurement using Hook method and also compare the same with other optical diagnostic techniques (White light absorption and UV absorption) for Li vapor density measurements. (author)

  3. 30 CFR 77.1301 - Explosives; magazines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosives; magazines. 77.1301 Section 77.1301... and Blasting § 77.1301 Explosives; magazines. (a) Detonators and explosives other than blasting agents shall be stored in magazines. (b) Detonators shall not be stored in the same magazine with explosives...

  4. Explosives mimic for testing, training, and monitoring

    Science.gov (United States)

    Reynolds, John G.; Durban, Matthew M.; Gash, Alexander E.; Grapes, Michael D.; Kelley, Ryan S.; Sullivan, Kyle T.

    2018-02-13

    Additive Manufacturing (AM) is used to make mimics for explosives. The process uses mixtures of explosives and matrices commonly used in AM. The explosives are formulated into a mixture with the matrix and printed using AM techniques and equipment. The explosive concentrations are kept less than 10% by wt. of the mixture to conform to requirements of shipping and handling.

  5. 8. Peaceful uses of nuclear explosions

    International Nuclear Information System (INIS)

    Musilek, L.

    1992-01-01

    The chapter deals with peaceful uses of nuclear explosions. Described are the development of the underground nuclear explosion, properties of radionuclides formed during the explosion, their distribution, the release of radioactive products of underground nuclear explosions into the air, their propagation in the atmosphere, and fallout in the landscape. (Z.S.). 1 tab., 8 figs., 19 refs

  6. Computer simulation of explosion crater in dams with different buried depths of explosive

    Science.gov (United States)

    Zhang, Zhichao; Ye, Longzhen

    2018-04-01

    Based on multi-material ALE method, this paper conducted a computer simulation on the explosion crater in dams with different buried depths of explosive using LS-DYNA program. The results turn out that the crater size increases with the increase of buried depth of explosive at first, but closed explosion cavity rather than a visible crater is formed when the buried depth of explosive increases to some extent. The soil in the explosion cavity is taken away by the explosion products and the soil under the explosion cavity is compressed with its density increased. The research can provide some reference for the anti-explosion design of dams in the future.

  7. Large eddy simulation and experimental study on vented gasoline-air mixture explosions in a semi-confined obstructed pipe.

    Science.gov (United States)

    Li, Guoqing; Du, Yang; Wang, Shimao; Qi, Sheng; Zhang, Peili; Chen, Wenzhuo

    2017-10-05

    In this work, LES simulation coupled with a TFC sub-grid combustion model has been performed in a semi-confined pipe (L/D=10, V=10L) in the presence of four hollow-square obstacles (BR=49.8%) with circular hollow cross-section, in order to study the premixed gasoline-air mixture explosions. The comparisons between simulated results and experimental results have been conducted. It was found that the simulated results were in good agreement with experimental data in terms of flame structures, flame locations and overpressure time histories. Moreover, the interaction between flame propagation process and obstacles, overpressure dynamics were analyzed. In addition, the effects of initial gasoline vapor concentration (lean (ϕ=1.3%), stoichiometric (ϕ=1.7%) and rich (ϕ=2.1%)), and the number of obstacles (from 1 to 4) were also investigated by experiments. Some of the experimental results have been compared with the literature data. It is found that the explosion parameters of gasoline-air mixtures (e.g. the maximum overpressure peaks, average overpressure growth rates, etc.) are different from some other fuels such as hydrogen, methane and LPG, etc. Copyright © 2017. Published by Elsevier B.V.

  8. Measurement and analysis of transient vaporization in oxide fuel materials

    International Nuclear Information System (INIS)

    Benson, D.A.; Bergeron, E.G.

    1979-01-01

    This paper describes a series of experiments in which samples are heated to produce high vapor pressure states in times of 10 -6 to 10 -3 seconds. Experimental measurements of vapor pressures over fresh UO 2 from the pulsed electron beam and pulsed reactor heating tests are presented and compared with other high temperature data. The interpretation of the vapor pressure measured in the tests is discussed in detail. Effects of original sample stoichiometry, chemical interactions with the container and non-equilibrium evaporation due to induced temperature gradients are discussed. Special attention is given to dynamic behavior in rapid heating and vaporization of the oxide due to chemical non-equilibrium. Finally, similar projected reactor experiments on irradiated fuel are described and vapor pressure predictions made using available equilibrium models. A discussion of information accessible from such future tests and its importance is presented. (orig.) [de

  9. Measurement and analysis of transient vaporization in oxide fuel materials

    International Nuclear Information System (INIS)

    Gorham-Bergeron, E.; Benson, D.A.

    1978-01-01

    A series of experiments is described in which samples are heated to produce high vapor pressure states in times of 10 -6 to 10 -3 seconds. Experimental measurements of vapor pressures over fresh UO 2 from the pulsed electron beam and pulsed reactor heating tests are presented and compared with other high temperature data. The interpretation of the vapor pressures measured in the tests is discussed in detail. Effects of original sample stoichiometry, chemical interactions with the container and non-equilibrium evaporation due to induced temperature gradients are discussed. Special attention is given to dynamic behavior in rapid heating and vaporization of the oxide due to chemical nonequilibrium. Finally, similar projected reactor experiments on irradiated fuel are described and vapor pressure predictions made using available equilibrium models. A discussion of information accessible from such future tests and its importance is presented

  10. Explosive Characteristics of Carbonaceous Nanoparticles

    Science.gov (United States)

    Turkevich, Leonid; Fernback, Joseph; Dastidar, Ashok

    2013-03-01

    Explosion testing has been performed on 20 codes of carbonaceous particles. These include SWCNTs (single-walled carbon nanotubes), MWCNTs (multi-walled carbon nanotubes), CNFs (carbon nanofibers), graphene, diamond, fullerene, carbon blacks and graphites. Explosion screening was performed in a 20 L explosion chamber (ASTM E1226-10 protocol), at a (dilute) concentration of 500 g/m3, using a 5 kJ ignition source. Time traces of overpressure were recorded. Samples exhibited overpressures of 5-7 bar, and deflagration index KSt = V1/3 (dp/pt)max ~ 10 - 80 bar-m/s, which places these materials in European Dust Explosion Class St-1 (similar to cotton and wood dust). There was minimal variation between these different materials. The explosive characteristics of these carbonaceous powders are uncorrelated with particle size (BET specific surface area). Additional tests were performed on selected materials to identify minimum explosive concentration [MEC]. These materials exhibit MEC ~ 101 -102 g/m3 (lower than the MEC for coals). The concentration scans confirm that the earlier screening was performed under fuel-rich conditions (i.e. the maximum over-pressure and deflagration index exceed the screening values); e.g. the true fullerene KSt ~ 200 bar-m/s, placing it borderline St-1/St-2. Work supported through the NIOSH Nanotechnology Research Center (NTRC)

  11. Recent Advances in Understanding Large Scale Vapour Explosions

    International Nuclear Information System (INIS)

    Board, S.J.; Hall, R.W.

    1976-01-01

    In foundries, violent explosions occur occasionally when molten metal comes into contact with water. If similar explosions can occur with other materials, hazardous situations may arise for example in LNG marine transportation accidents, or in liquid cooled reactor incidents when molten UO 2 contacts water or sodium coolant. Over the last 10 years a large body of experimental data has been obtained on the behaviour of small quantities of hot material in contact with a vaporisable coolant. Such experiments generally give low energy yields, despite producing fine fragmentation of the molten material. These events have been interpreted in terms of a wide range of phenomena such as violent boiling, liquid entrainment, bubble collapse, superheat, surface cracking and many others. Many of these studies have been aimed at understanding the small scale behaviour of the particular materials of interest. However, understanding the nature of the energetic events which were the original cause for concern may also be necessary to give confidence that violent events cannot occur for these materials in large scale situations. More recently, there has been a trend towards larger experiments and some of these have produced explosions of moderately high efficiency. Although occurrence of such large scale explosions can depend rather critically on initial conditions in a way which is not fully understood, there are signs that the interpretation of these events may be more straightforward than that of the single drop experiments. In the last two years several theoretical models for large scale explosions have appeared which attempt a self contained explanation of at least some stages of such high yield events: these have as their common feature a description of how a propagating breakdown of an initially quasi-stable distribution of materials is induced by the pressure and flow field caused by the energy release in adjacent regions. These models have led to the idea that for a full

  12. Pyroshock Prediction of Ridge-Cut Explosive Bolts Using Hydrocodes

    Directory of Open Access Journals (Sweden)

    Juho Lee

    2016-01-01

    Full Text Available Pyrotechnic release devices such as explosive bolts are prevalent for many applications due to their merits: high reliability, high power-to-weight ratio, reasonable cost, and more. However, pyroshock generated by an explosive event can cause failures in electric components. Although pyroshock propagations are relatively well understood through many numerical and experimental studies, the prediction of pyroshock generation is still a very difficult problem. This study proposes a numerical method for predicting the pyroshock of a ridge-cut explosive bolt using a commercial hydrocode (ANSYS AUTODYN. A numerical model is established by integrating fluid-structure interaction and complex material models for high explosives and metals, including high explosive detonation, shock wave transmission and propagation, and stress wave propagation. To verify the proposed numerical scheme, pyroshock measurement experiments of the ridge-cut explosive bolts with two types of surrounding structures are performed using laser Doppler vibrometers (LDVs. The numerical analysis results provide accurate prediction in both the time (acceleration and frequency domains (maximax shock response spectra. In maximax shock response spectra, the peaks due to vibration modes of the structures are observed in both the experimental and numerical results. The numerical analysis also helps to identify the pyroshock generation source and the propagation routes.

  13. Gas pollutants from detonation and combustion of industrial explosives

    Energy Technology Data Exchange (ETDEWEB)

    Campos, J.; Pines, A.; Gois, J.C.; Portugal, A. (University of Coimbra, Coimbra (Portugal). Mechanical Engineering Dept.)

    1993-01-01

    The potential hazards of fumes, from blasting operations in underground mines, have long been recognised. Beyond this normal use of explosives, there are also large amounts of energy substances which cannot be used because their life time is outdated or they are not within the minimal quality requirements. There is a lack of information concerning tests, procedures and theoretical predictions of pollutant concentrations in fumes from detonation and combustion operations with industrial explosives. The most common industrial explosives in Portugal are ammonium nitrate-fuel oil compositions (anfo), and dynamite. Recently, ammonium nitrate based emulsion explosives are more and more used in industrial applications. This paper presents the structure and fundamental thermodynamic equations of THOR computer code to calculate the combustion and detonation products (CO[sub 2], CO, H[sub 2]O, N[sub 2], O[sub 2], H[sub 2], OH, NO, H, N, O, HCN, NH[sub 3], NO[sub 2], N[sub 2]O, CH[sub 4] gases and two kinds of solid carbon - graphite and diamond) for the minimum value of Gibbs free energy, using three well known equations of state - BKW, H9 and H12. Detonation experiments are described and gas analysis discussed. Measured pollutants concentrations (CO, CO[sub 2], NO and NO[sub 2]), as a function of volume of explosion chamber, prove the dependence of expansion mechanisms on CO and NO formation and recombination and validate theoretical predictions. Incineration of explosives in a fluidised bed is described. Products composition from isobare adiabatic combustion of selected explosives has been calculated and correlated with previous calculations for a detonation regime. The obtained results demonstrate the possibility of predicting gas composition of detonation and combustion products of industrial explosives. 22 refs., 14 figs., 1 tab.

  14. Approximating the r-process on earth with thermonuclear explosions

    International Nuclear Information System (INIS)

    Becker, S.A.

    1992-01-01

    The astrophysical r-process can be approximately simulated in certain types of thermonuclear explosions. Between 1952 and 1969 twenty-three nuclear tests were fielded by the United States which had as one of their objectives the production of heavy transuranic elements. Of these tests, fifteen were at least partially successful. Some of these shots were conducted under the project Plowshare Peaceful Nuclear Explosion Program as scientific research experiments. A review of the program, target nuclei used, and heavy element yields achieved, will be presented as well as discussion of plans for a new experiment in a future nuclear test

  15. Vapor pressure and enthalpy of vaporization of linear aliphatic alkanediamines

    International Nuclear Information System (INIS)

    Pozdeev, Vasiliy A.; Verevkin, Sergey P.

    2011-01-01

    Highlights: → We measured vapor pressure of diamines H 2 N-(CH 2 ) n -NH 2 with n = 3 to 12. → Vaporization enthalpies at 298 K were derived. → We examined consistency of new and available in the literature data. → Enthalpies of vaporization show linear dependence on numbers n. → Enthalpies of vaporization correlate linearly with Kovat's indices. - Abstract: Vapor pressures and the molar enthalpies of vaporization of the linear aliphatic alkanediamines H 2 N-(CH 2 ) n -NH 2 with n = (3 to 12) have been determined using the transpiration method. A linear correlation of enthalpies of vaporization (at T = 298.15 K) of the alkanediamines with the number n and with the Kovat's indices has been found, proving the internal consistency of the measured data.

  16. Explosive coalescence of magnetic islands and explosive particle acceleration

    International Nuclear Information System (INIS)

    Tajima, T.; Sakai, J.I.

    1985-07-01

    An explosive reconnection process associated with the nonlinear evolution of the coalescence instability is found through studies of the electromagnetic particle simulation and the magnetohydrodynamic particle simulation. The explosive coalescence is a process of magnetic collapse, in which we find the magnetic and electrostatic field energies and temperatures (ion temperature in the coalescing direction, in particular) explode toward the explosion time t 0 as (t 0 - t)/sup -8/3/, (t 0 - t) -4 , and (t 0 - t)/sup -8/3/, respectively for a canonical case. Single-peak, double-peak, and triple-peak structures of magnetic energy, temperature, and electrostatic energy, respectively, are observed on the simulation as overshoot amplitude oscillations and are theoretically explained. The heuristic model of Brunel and Tajima is extended to this explosive coalescence in order to extract the basic process. Since the explosive coalescence exhibits self-similarity, a temporal universality, we theoretically search for a self-similar solution to the two-fluid plasma equations

  17. Chemical, Biological, and Explosive Sensors for Field Measurements

    International Nuclear Information System (INIS)

    Kyle, Kevin; Manard, Manuel; Weeks, Stephan

    2009-01-01

    Special Technologies Laboratory (STL) is developing handheld chemical, biological, and explosive (CBE) detection systems and sensor motes for wireless networked field operations. The CBE sensors are capable of detecting and identifying multiple targeted toxic industrial chemicals (TICs) and high-explosive vapor components. The CBE devices are based on differential mobility spectrometry (DMS) coupled with fast gas chromatography (GC) or mass spectrometry. The systems all include the concepts of: (1) Direct air/particulate 'smart' sampling; (2) Selective, continuous real-time (∼1 sec) alert monitoring using DMS; and (3) Highly selective, rapid dual technology separation/verification analysis The biosensor technology is based on Raman aerosol particle flow cytometry for target detection and identification. Monitoring and identifying trace level chemical vapors directly from ambient air will allow First Responders to quickly adapt situational response strategies and personal protective equipment needs to the specific response scenario being encountered. First Responders require great confidence in the measurements and ability of a given system to detect CBE below threshold levels without interferences. The concept of determining the background matrix in near real-time to allow subsequent automated field-programmable method selection and cueing of high-value assets in a wide range of environs will be presented. This provides CBE information for decisions prior to First Responders entering the response site or sending a portable mobile unit for a remote site survey of the hazards. The focus is on real-time information needed by those responsible for emergency response and national security

  18. Observation and particle simulation of vaporized W, Mo, and Be in PISCES-B plasma for vapor-shielding studies

    Directory of Open Access Journals (Sweden)

    K. Ibano

    2017-08-01

    Full Text Available Interactions of Tungsten (W, Molybdenum (Mo, and Beryllium (Be vapors with a steady-state plasma were studied by the PISCES-B liner plasma experiments as well as Particle-In-Cell (PIC simulations for the understanding of vapor-shielding phenomena. Effective cooling of the plasma by laser-generated Be vapor was observed in PISCES-B. On the other hand, no apparent cooling was observed for W and Mo vapors. The PIC simulation explains these experimental observations of the difference between low-Z and high-Z vapors. Decrease of electron temperature due to the vapor ejection was observed in case of a simulation of the Be vapor. As for the W vapor, it was found that the plasma cooling is localized only near the wall at a higher electron density plasma (∼1019m−3. On the other hand, the appreciable plasma cooling can be observed in a lower density plasma (∼1018m−3 for the W vapor.

  19. Vapor pressures and enthalpies of vaporization of a series of γ and δ-lactones by correlation gas chromatography

    International Nuclear Information System (INIS)

    Kozlovskiy, Mikhail; Gobble, Chase; Chickos, James

    2014-01-01

    Highlights: • The vaporization enthalpies of γ-octanolactone, γ- and δ-undecanolactone and γ and δ-dodecanolactone are reported. • Equations for predicting the vapor pressures over the temperature range T = (298.15 to 350) K are provided. • Vaporization enthalpies are compared to predicted values. - Abstract: The vaporization enthalpies of γ-octanolactone, γ- and δ-undecanolactone and γ and δ-dodecanolactone used commercially as flavor ingredients are reported as are their vapor pressures over the temperature range T = (298.15 to 350) K. Vaporization enthalpies at T = 298.15 K of: (66.0 ± 3.9), (79.4 ± 4.4), (80.1 ± 4.5), (83.9 ± 4.6), and (84.61 ± 4.7) kJ · mol −1 and vapor pressures also at T = 298.15 K of: (2.8 ± 0.9), (0.12 ± 0.05), (0.09 ± 0.04), (0.04 ± 0.02), and (0.03 ± 0.02) Pa, respectively, have been evaluated by correlation gas chromatography experiments. The vaporization enthalpies of the lactones studied are reproduced within ±0.5 kJ · mol −1 using a group additivity scheme reported previously for γ- and δ-lactones. The vaporization enthalpies of the γ- and δ-lactones are compared to a similar series of ω-lactones

  20. A case of intermittent explosive disorder

    Directory of Open Access Journals (Sweden)

    Amitabh Saha

    2010-01-01

    Full Text Available A case of impulse control disorder was observed and managed. In this case, the serving soldier of the Indian army presented with explosive outbursts of extreme violence and anger, which was not clearly directed. Following this act of aggression, he would experience a sense of gratification and relief. The episodes were recurrent and resulted in assaults or destruction of property. The aggression displayed was out of proportion to any perceived provocation and the individual felt increasing tension or arousal before committing the act. He did not have any feelings of regret, remorse or guilt about the behavior.

  1. Research on an improved explosive emission cathode

    International Nuclear Information System (INIS)

    Liu Guozhi; Sun Jun; Shao Hao; Chen Changhua; Zhang Xiaowei

    2009-01-01

    This paper presents a physical description of the cathode plasma process of an explosive emission cathode (EEC) and experimental results on a type of oil-immersed graphite EEC. It is believed that the generation of a cathode plasma is mainly dependent on the state of the cathode surface, and that adsorbed gases and dielectrics on the cathode surface play a leading role in the formation of the cathode plasma. Based on these ideas, a type of oil-immersed graphite EEC is proposed and fabricated. The experiments indicate that the oil-immersed cathodes have improved emissive properties and longer lifetimes.

  2. Molecular Outflows: Explosive versus Protostellar

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, Luis A.; Rodríguez, Luis F.; Palau, Aina; Loinard, Laurent [Instituto de Radioastronomía y Astrofísica, UNAM, Apdo. Postal 3-72 (Xangari), 58089 Morelia, Michoacán, México (Mexico); Schmid-Burgk, Johannes [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121, Bonn (Germany)

    2017-02-10

    With the recent recognition of a second, distinctive class of molecular outflows, namely the explosive ones not directly connected to the accretion–ejection process in star formation, a juxtaposition of the morphological and kinematic properties of both classes is warranted. By applying the same method used in Zapata et al., and using {sup 12}CO( J = 2-1) archival data from the Submillimeter Array, we contrast two well-known explosive objects, Orion KL and DR21, to HH 211 and DG Tau B, two flows representative of classical low-mass protostellar outflows. At the moment, there are only two well-established cases of explosive outflows, but with the full availability of ALMA we expect that more examples will be found in the near future. The main results are the largely different spatial distributions of the explosive flows, consisting of numerous narrow straight filament-like ejections with different orientations and in almost an isotropic configuration, the redshifted with respect to the blueshifted components of the flows (maximally separated in protostellar, largely overlapping in explosive outflows), the very-well-defined Hubble flow-like increase of velocity with distance from the origin in the explosive filaments versus the mostly non-organized CO velocity field in protostellar objects, and huge inequalities in mass, momentum, and energy of the two classes, at least for the case of low-mass flows. Finally, all the molecular filaments in the explosive outflows point back to approximately a central position (i.e., the place where its “exciting source” was located), contrary to the bulk of the molecular material within the protostellar outflows.

  3. Mass Spectrometric Analysis of Eight Common Chemical Explosives Using Ion Trap Mass Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sehwan; Lee, Jihyeon; KIm, Jeongkwon [Chungnam National Univ., Daejeon (Korea, Republic of); Cho, Soo Gyeong; Goh, Eun Mee [Agency for Defense Development, Daejeon (Korea, Republic of); Lee, Sungman; Koh, Sungsuk [Sensor Tech Inc., Seoul (Korea, Republic of)

    2013-12-15

    Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either [M.H]{sup -} for TNT and DNT or [M]{sup ·-}. for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i. e., [M+HCOO]{sup -}. These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available.

  4. Mass Spectrometric Analysis of Eight Common Chemical Explosives Using Ion Trap Mass Spectrometer

    International Nuclear Information System (INIS)

    Park, Sehwan; Lee, Jihyeon; KIm, Jeongkwon; Cho, Soo Gyeong; Goh, Eun Mee; Lee, Sungman; Koh, Sungsuk

    2013-01-01

    Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either [M.H] - for TNT and DNT or [M] ·- . for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i. e., [M+HCOO] - . These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available

  5. Vapor condensation device

    International Nuclear Information System (INIS)

    Sakurai, Manabu; Hirayama, Fumio; Kurosawa, Setsumi; Yoshikawa, Jun; Hosaka, Seiichi.

    1992-01-01

    The present invention enables to separate and remove 14 C as CO 3 - ions without condensation in a vapor condensation can of a nuclear facility. That is, the vapor condensation device of the nuclear facility comprises (1) a spray pipe for spraying an acidic aqueous solution to the evaporation surface of an evaporation section, (2) a spray pump for sending the acidic aqueous solution to the spray pipe, (3) a tank for storing the acidic aqueous solution, (4) a pH sensor for detecting pH of the evaporation section, (5) a pH control section for controlling the spray pump, depending on the result of the detection of the pH sensor. With such a constitution, the pH of liquid wastes on the vaporization surface is controlled to 7 by spraying an aqueous solution of dilute sulfuric acid to the evaporation surface, thereby enabling to increase the transfer rate of 14 C to condensates to 60 to 70%. If 14 C is separated and removed as a CO 2 gas from the evaporation surface, the pH of the liquid wastes returns to the alkaline range of 9 to 10 and the liquid wastes are returned to a heating section. The amount of spraying the aqueous solution of dilute sulfuric acid can be controlled till the pH is reduced to 5. (I.S.)

  6. Covering sources of toxic vapors with foam

    International Nuclear Information System (INIS)

    Aue, W. P.; Guidetti, F.

    2009-01-01

    In a case of chemical terrorism, first responders might well be confronted with a liquid source of toxic vapor which keeps spreading out its hazardous contents. With foam as an efficient and simple means, such a source could be covered up in seconds and the spread of vapors mitigated drastically. Once covered, the source could then wait for a longer time to be removed carefully and professionally by a decontamination team. In order to find foams useful for covering up toxic vapor sources, a large set of measurements has been performed in order to answer the following questions: - Which foams could be used for this purpose? - How thick should the foam cover be? - For how long would such a foam cover be effective? - Could the practical application of foam cause a spread of the toxic chemical? The toxic vapors sources included GB, GD and HD. Among the foams were 10 fire fighter foams (e.g. AFFF, protein) and the aqueous decontamination foam CASCAD. Small scale experiments showed that CASCAD is best suited for covering a toxic source; a 10 cm layer of it covers and decontaminates GB. The large scale experiments confirmed that any fire fighter foam is a suitable cover for a longer or shorter period.(author)

  7. Understanding the shock and detonation response of high explosives at the continuum and meso scales

    Science.gov (United States)

    Handley, C. A.; Lambourn, B. D.; Whitworth, N. J.; James, H. R.; Belfield, W. J.

    2018-03-01

    The shock and detonation response of high explosives has been an active research topic for more than a century. In recent years, high quality data from experiments using embedded gauges and other diagnostic techniques have inspired the development of a range of new high-fidelity computer models for explosives. The experiments and models have led to new insights, both at the continuum scale applicable to most shock and detonation experiments, and at the mesoscale relevant to hotspots and burning within explosive microstructures. This article reviews the continuum and mesoscale models, and their application to explosive phenomena, gaining insights to aid future model development and improved understanding of the physics of shock initiation and detonation propagation. In particular, it is argued that "desensitization" and the effect of porosity on high explosives can both be explained by the combined effect of thermodynamics and hydrodynamics, rather than the traditional hotspot-based explanations linked to pressure-dependent reaction rates.

  8. A sensitive, handheld vapor sensor based on microcantilevers

    Science.gov (United States)

    Pinnaduwage, L. A.; Hedden, D. L.; Gehl, A.; Boiadjiev, V. I.; Hawk, J. E.; Farahi, R. H.; Thundat, T.; Houser, E. J.; Stepnowski, S.; McGill, R. A.; Deel, L.; Lareau, R. T.

    2004-11-01

    We report the development of a handheld sensor based on piezoresistive microcantilevers that does not depend on optical detection, yet has high detection sensitivity. The sensor is able to detect vapors from the plastic explosives pentaerythritol tetranitrate and hexahydro-1,3,5-triazine at levels below 10 parts per trillion within few seconds of exposure under ambient conditions. A differential measurement technique has yielded a rugged sensor that is unaffected by vibration and is able to function as a "sniffer." The microelectromechanical system sensor design allows for the incorporation of hundreds of microcantilevers with suitable coatings in order to achieve sufficient selectivity in the future, and thus could provide an inexpensive, unique platform for the detection of chemical, biological, and explosive materials.

  9. Electromagnetic field effects in explosives

    Science.gov (United States)

    Tasker, Douglas

    2009-06-01

    Present and previous research on the effects of electromagnetic fields on the initiation and detonation of explosives and the electromagnetic properties of explosives are reviewed. Among the topics related to detonating explosives are: measurements of conductivity; enhancement of performance; and control of initiation and growth of reaction. Hayes...()^1 showed a strong correlation of peak electrical conductivity with carbon content of the detonation products. Ershov.......^2 linked detailed electrical conductivity measurements with reaction kinetics and this work was extended to enhance detonation performance electrically;...^3 for this, electrical power densities of the order of 100 TW/m^2 of explosive surface normal to the detonation front were required. However, small electrical powers are required to affect the initiation and growth of reaction.......^4,5 A continuation of this work will be reported. LA-UR 09-00873 .^1 B. Hayes, Procs. of 4th Symposium (International) on Detonation (1965), p. 595. ^2 A. Ershov, P. Zubkov, and L. Luk'yanchikov, Combustion, Explosion, and Shock Waves 10, 776-782 (1974). ^3 M. Cowperthwaite, Procs. 9th Detonation Symposium (1989), p. 388-395. ^4 M. A. Cook and T. Z. Gwyther, ``Influence of Electric Fields on Shock to Detonation Transition,'' (1965). ^5 D. Salisbury, R. Winter, and L. Biddle, Procs. of the APS Topical Conference on Shock Compression of Condensed Matter (2005) p. 1010-1013.

  10. VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS

    Energy Technology Data Exchange (ETDEWEB)

    Eric M. Suuberg; Vahur Oja

    1997-07-01

    This project had as its main focus the determination of vapor pressures of coal pyrolysis tars. It involved performing measurements of these vapor pressures and from them, developing vapor pressure correlations suitable for use in advanced pyrolysis models (those models which explicitly account for mass transport limitations). This report is divided into five main chapters. Each chapter is a relatively stand-alone section. Chapter A reviews the general nature of coal tars and gives a summary of existing vapor pressure correlations for coal tars and model compounds. Chapter B summarizes the main experimental approaches for coal tar preparation and characterization which have been used throughout the project. Chapter C is concerned with the selection of the model compounds for coal pyrolysis tars and reviews the data available to us on the vapor pressures of high boiling point aromatic compounds. This chapter also deals with the question of identifying factors that govern the vapor pressures of coal tar model materials and their mixtures. Chapter D covers the vapor pressures and heats of vaporization of primary cellulose tars. Chapter E discusses the results of the main focus of this study. In summary, this work provides improved understanding of the volatility of coal and cellulose pyrolysis tars. It has resulted in new experimentally verified vapor pressure correlations for use in pyrolysis models. Further research on this topic should aim at developing general vapor pressure correlations for all coal tars, based on their molecular weight together with certain specific chemical characteristics i.e. hydroxyl group content.

  11. Sensitivity of numerical dispersion modeling to explosive source parameters

    International Nuclear Information System (INIS)

    Baskett, R.L.; Cederwall, R.T.

    1991-01-01

    The calculation of downwind concentrations from non-traditional sources, such as explosions, provides unique challenges to dispersion models. The US Department of Energy has assigned the Atmospheric Release Advisory Capability (ARAC) at the Lawrence Livermore National Laboratory (LLNL) the task of estimating the impact of accidental radiological releases to the atmosphere anywhere in the world. Our experience includes responses to over 25 incidents in the past 16 years, and about 150 exercises a year. Examples of responses to explosive accidents include the 1980 Titan 2 missile fuel explosion near Damascus, Arkansas and the hydrogen gas explosion in the 1986 Chernobyl nuclear power plant accident. Based on judgment and experience, we frequently estimate the source geometry and the amount of toxic material aerosolized as well as its particle size distribution. To expedite our real-time response, we developed some automated algorithms and default assumptions about several potential sources. It is useful to know how well these algorithms perform against real-world measurements and how sensitive our dispersion model is to the potential range of input values. In this paper we present the algorithms we use to simulate explosive events, compare these methods with limited field data measurements, and analyze their sensitivity to input parameters. 14 refs., 7 figs., 2 tabs

  12. Enhanced coupling and decoupling of underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Terhune, R.W.; Snell, C.M.; Rodean, H.C.

    1979-09-04

    The seismic coupling efficiency of nuclear explosions was studied in granite by means of computer calculations as a function of scaled explosion source radius. The scaled source radii were varied from 0.1 m/kt/sup 1/3/ (point source) to 20 m/kt/sup 1/3/ (representing a nearly full decoupling cavity). It was found that seismic coupling efficiency is at a maximum when the scaled source radius is approximately 2 m/kt/sup 1/3/. The primary cause of this maximum in seismic wave source strength is the effect of initial source radius on peak particle velocity and pulse duration of the outgoing elastic wave. A secondary cause is that rock vaporization (an energy sink) does not occur for scaled source radii somewhat greater than 1 m/kt/sup 1/3/. Therefore, for scaled source radii greater than 1 m/kt/sup 1/3/, there is additional energy available for seismic wave generations. Available data for some nuclear explosions at the Nevada Test Site do not provide sufficient evidence to either support or negate the enhanced coupling that is indicated by calculations at scaled source radii of 1-2 m/kt/sup 1/3/.

  13. Enhanced coupling and decoupling of underground nuclear explosions

    International Nuclear Information System (INIS)

    Terhune, R.W.; Snell, C.M.; Rodean, H.C.

    1979-01-01

    The seismic coupling efficiency of nuclear explosions was studied in granite by means of computer calculations as a function of scaled explosion source radius. The scaled source radii were varied from 0.1 m/kt/sup 1/3/ (point source) to 20 m/kt/sup 1/3/ (representing a nearly full decoupling cavity). It was found that seismic coupling efficiency is at a maximum when the scaled source radius is approximately 2 m/kt/sup 1/3/. The primary cause of this maximum in seismic wave source strength is the effect of initial source radius on peak particle velocity and pulse duration of the outgoing elastic wave. A secondary cause is that rock vaporization (an energy sink) does not occur for scaled source radii somewhat greater than 1 m/kt/sup 1/3/. Therefore, for scaled source radii greater than 1 m/kt/sup 1/3/, there is additional energy available for seismic wave generations. Available data for some nuclear explosions at the Nevada Test Site do not provide sufficient evidence to either support or negate the enhanced coupling that is indicated by calculations at scaled source radii of 1-2 m/kt/sup 1/3/

  14. Deposition of D{sub 2}O from air to plant and soil during an experiment of D{sub 2}O vapor release into a vinyl house

    Energy Technology Data Exchange (ETDEWEB)

    Atarashi, M.; Amano, H. [Japan Atomic Energy Res. Inst., Naka, Ibaraki (Japan). Dept. of Environ. Safety Res.; Ichimasa, M.; Ichimasa, Y. [Faculty of Science, Ibaraki University, Mito-shi, Ibaraki 310 (Japan)

    1998-09-01

    Deuterium, a stable isotope of tritium, was released into a vinyl house in autumn 1995 and summer 1996 to study the transfer of tritium from air to plant and soil. Temporal variation of D{sub 2}O concentrations in plant and soil water, and plant physiological parameters such as transpiration rate and leaf temperature, were measured during these experiments. D{sub 2}O concentrations of plants were fitted to a first order kinetic model: C{sub p}=C{sub max} (1-e{sup -kt}), where C{sub p} is the D{sub 2}O concentrations in plants at time t, C{sub max} is the steady-state concentration in plants and k is the rate constant. The rate constant was also calculated using measured plant physiological parameters for comparison. The D{sub 2}O uptake by paddy rice was most rapid and the value of k was 3.63{+-}0.31 h{sup -1} followed by radish, cherry tomato, komatsuna and orange. The day/night concentration ratio for cherry tomato and orange was higher than that for radish and komatsuna. (orig.) 8 refs.

  15. Deposition of D2O from air to plant and soil during an experiment of D2O vapor release into a vinyl house

    International Nuclear Information System (INIS)

    Atarashi, M.; Amano, H.

    1998-01-01

    Deuterium, a stable isotope of tritium, was released into a vinyl house in autumn 1995 and summer 1996 to study the transfer of tritium from air to plant and soil. Temporal variation of D 2 O concentrations in plant and soil water, and plant physiological parameters such as transpiration rate and leaf temperature, were measured during these experiments. D 2 O concentrations of plants were fitted to a first order kinetic model: C p =C max (1-e -kt ), where C p is the D 2 O concentrations in plants at time t, C max is the steady-state concentration in plants and k is the rate constant. The rate constant was also calculated using measured plant physiological parameters for comparison. The D 2 O uptake by paddy rice was most rapid and the value of k was 3.63±0.31 h -1 followed by radish, cherry tomato, komatsuna and orange. The day/night concentration ratio for cherry tomato and orange was higher than that for radish and komatsuna. (orig.)

  16. Intensive evaporation and boiling of a heterogeneous liquid droplet with an explosive disintegration in high-temperature gas area

    Directory of Open Access Journals (Sweden)

    Piskunov Maxim V.

    2016-01-01

    Full Text Available The using of the high-speed (not less than 105 frames per second video recording tools (“Phantom” and the software package ("TEMA Automotive" allowed carrying out an experimental research of laws of intensive vaporization with an explosive disintegration of heterogeneous (with a single solid nontransparent inclusion liquid droplet (by the example of water in high-temperature (500-800 K gases (combustion products. Times of the processes under consideration and stages (liquid heat-up, evaporation from an external surface, bubble boiling at internal interfaces, growth of bubble sizes, explosive droplet breakup were established. Necessary conditions of an explosive vaporization of a heterogeneous droplet were found out. Mechanisms of this process and an influence of properties of liquid and inclusion material on them were determined.

  17. Calculating overpressure from BLEVE explosions

    Energy Technology Data Exchange (ETDEWEB)

    Planas-Cuchi, E.; Casal, J. [Universitat Politecnica de Catalunya, Barcelona (Spain). Department of Chemical Engineering, Centre for Technological Risk Studies; Salla, J.M. [Universitat Politecnica de Catalunya, Barcelona (Spain). Department of Heat Engines

    2004-11-01

    Although a certain number of authors have analyzed the prediction of boiling liquid expanding vapour explosion (BLEVE) and fireball effects, only very few of them have proposed methodologies for predicting the overpressure from such explosions. In this paper, the methods previously published are discussed and shown to introduce a significant overestimation due to erroneous thermodynamic assumptions - ideal gas behaviour and isentropic vapour expansion - on which they are based (in fact, they give the maximum value of overpressure which can be caused by a BLEVE). A new approach is proposed, based on the - more realistic - assumption of an adiabatic and irreversible expansion process; the real properties of the substance involved in the explosion are used. The two methods are compared through the application to a given case. (author)

  18. Evidence for nearby supernova explosions

    International Nuclear Information System (INIS)

    Benitez, Narciso; Maiz-Apellaniz, Jesus; Canelles, Matilde

    2002-01-01

    Supernova (SN) explosions are one of the most energetic--and potentially lethal--phenomena in the Universe. We show that the Scorpius-Centaurus OB association, a group of young stars currently located at ∼130 pc from the Sun, has generated 20 SN explosions during the last 11 Myr, some of them probably as close as 40 pc to our planet. The deposition on Earth of 60 Fe atoms produced by these explosions can explain the recent measurements of an excess of this isotope in deep ocean crust samples. We propose that ∼2 Myr ago, one of the SNe exploded close enough to Earth to seriously damage the ozone layer, provoking or contributing to the Pliocene-Pleistocene boundary marine extinction

  19. Fracture analysis of tube boiler for physical explosion accident.

    Science.gov (United States)

    Kim, Eui Soo

    2017-09-01

    Material and failure analysis techniques are key tools for determining causation in case of explosive and bursting accident result from material and process defect of product in the field of forensic science. The boiler rupture generated by defect of the welding division, corrosion, overheating and degradation of the material have devastating power. If weak division of boiler burner is fractured by internal pressure, saturated vapor and water is vaporized suddenly. At that time, volume of the saturated vapor and water increases up to thousands of volume. This failure of boiler burner can lead to a fatal disaster. In order to prevent an explosion and of the boiler, it is critical to introduce a systematic investigation and prevention measures in advance. In this research, the cause of boiler failure is investigated through forensic engineering method. Specifically, the failure mechanism will be identified by fractography using scanning electron microscopes (SEM) and Optical Microscopes (OM) and mechanical characterizations. This paper presents a failure analysis of household welding joints for the water tank of a household boiler burner. Visual inspection was performed to find out the characteristics of the fracture of the as-received material. Also, the micro-structural changes such as grain growth and carbide coarsening were examined by optical microscope. Detailed studies of fracture surfaces were made to find out the crack propagation on the weld joint of a boiler burner. It was concluded that the rupture may be caused by overheating induced by insufficient water on the boiler, and it could be accelerated by the metal temperature increase. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Water temperature and concentration measurements within the expanding blast wave of a high explosive

    International Nuclear Information System (INIS)

    Carney, J R; Lightstone, J M; Piecuch, S; Koch, J D

    2011-01-01

    We present an application of absorption spectroscopy to directly measure temperature and concentration histories of water vapor within the expansion of a high explosive detonation. While the approach of absorption spectroscopy is well established, the combination of a fast, near-infrared array, broadband light source, and rigid gauge allow the first application of time-resolved absorption measurements in an explosive environment. The instrument is demonstrated using pentaerythritol tetranitrate with a sampling rate of 20 kHz for 20 ms following detonation. Absorption by water vapor is measured between 1335 and 1380 nm. Water temperatures are determined by fitting experimental transmission spectra to a simulated database. Water mole fractions are deduced following the temperature assignment. The sources of uncertainty and their impact on the results are discussed. These measurements will aid the development of chemical-specific reaction models and the predictive capability in technical fields including combustion and detonation science

  1. Monitoring the airborne dust and water vapor in the low atmosphere of Mars: the MEDUSA experiment for the ESA ExoMars mission

    Science.gov (United States)

    Esposito, Francesca; Colangeli, Luigi; Palumbo, Pasquale; Della Corte, Vincenzo; Molfese, Cesare; Merrison, Jonathan; Nornberg, Per; Lopez-Moreno, J. J.; Rodriguez Gomez, Julio

    Dust and water vapour are fundamental components of Martian atmosphere. Dust amount varies with seasons and with the presence of local and global dust storms, but never drops entirely to zero. Aerosol dust has always played a fundamental role on the Martian climate. Dust interaction with solar and thermal radiation and the related condensation and evaporation processes influence the thermal structure and balance, and the dynamics (in terms of circulation) of the atmosphere. Water vapour is a minor constituent of the Martian atmosphere but it plays a fundamental role and it is important as indicator of seasonal climate changes. Moreover, the interest about the water cycle on local and global scales is linked to the fundamental function that water could have played in relation to the existence of living organisms on Mars. In view of tracing the past environmental conditions on Mars, that possibly favoured the appearing of life forms, it is important to study the present climate and its evolution, on which dust and water vapour have (and have had) strong influence. Moreover, nowadays, dust is a relevant agent that affects environmental conditions in the lower Martian atmosphere and, thus, may interact / interfere with any instrumentation delivered to Mars surface for in situ analyses. So, information on dust properties and deposition rate is also of great interest for future mission design. Knowledge of how much dust settles on solar arrays and the size and shape of particles will be crucial elements for designing missions that will operate by solar power for periods of several years and will have moving parts which will experience degradation by dust. This information is essential also for proper planning of future manned missions in relation to characterisation of environmental hazardous conditions. Little is known about dust structure and dynamics, so far. Size distribution is known only roughly and the mechanism of settling and rising into the atmosphere, the

  2. Support for the Harvard University Water Vapor and Total Water Instruments for the 2004 NASA WB57 Middle Latitude Cirrus Experiment

    Science.gov (United States)

    Anderson, James G.

    2005-01-01

    In order to improve our understanding of the role clouds play in the climate system, NASA is investing considerable effort in characterizing clouds with instruments ranging from passive remote sensors on board the EOS platforms, to the forthcoming active remote sensors on Cloudsat and Calipso. These missions, when taken together, have the capacity to advance our understanding of the coupling between various components of the hydrologic cycle and the atmospheric circulation, and hold the additional potential of leading to significant improvements in the characterization of cloud feedbacks in global models. This is especially true considering that several of these platforms will be flown in an identical orbit within several minutes of one another-a constellation of satellites known as the A-Train. The algorithms that are being implemented and developed to convert these new data streams from radiance and reflectivity measurements into geophysical parameters invariably rely on some set of simplifymg assumptions and empirical constants. Uncertainties in these relationships lead to poorly understood random and systematic errors in the retrieved properties. This lack of understanding introduces ambiguity in interpreting the data and in using the global data sets for their intended purposes. In light of this, a series of flights with the W57F was proposed to address certain specific issues related to the basic properties of mid latitude cirrus clouds: the NASA WE357 Middle Latitude Cirrus Experiment ("MidCiX"). The science questions addressed are: 1) Can cloud property retrieval algorithms developed for A-Train active and passive remote sensing measurements accurately characterize the microphysical properties of synoptic and convectively generated cirrus cloud systems? 2) What are the relationships between the cirrus particle mass, projected area, and particle size spectrum in various genre of cirrus clouds? 3) Does the present compliment of state of the art in situ cloud

  3. Fan tomography of the tropospheric water vapor for the calibration of the Ka band tracking of the Bepi-Colombo spacecraft (MORE experiment).

    Science.gov (United States)

    Barriot, Jean-Pierre; Serafini, Jonathan; Sichoix, Lydie

    2012-07-01

    The radiosciences Bepi-Colombo MORE experiment will use X/X, X/Ka and Ka/Ka band radio links to make accurate measurements of the spacecraft range and range rate. Tropospheric zenith wet delays range from 1.5 cm to 10 cm, with high variability (less than 1000 s) and will impair these accurate measurements. Conditions vary from summer (worse) to winter (better), from day (worse) to night (better). These wet delays cannot be estimated from ground weather measurements and alternative calibration methods should be used in order to cope with the MORE requirements (no more than 3 mm at 1000 s). Due to the Mercury orbit, MORE measurements will be performed by daylight and more frequently in summer than in winter (from Northern hemisphere). Two systems have been considered to calibrate this wet delay: Water Vapour Radiometers (WVRs) and GPS receivers. The Jet Propulsion Laboratory has developed a new class of WVRs reaching a 5 percent accuracy for the wet delay calibration (0.75 mm to 5 mm), but these WVRs are expensive to build and operate. GPS receivers are also routinely used for the calibration of data from NASA Deep Space probes, but several studies have shown that GPS receivers can give good calibration (through wet delay mapping functions) for long time variations, but are not accurate enough for short time variations (100 to 1000 s), and that WVRs must be used to efficiently calibrate the wet troposphere delays over such time spans. We think that such a calibration could be done by assimilating data from all the GNSS constellations (GPS, GLONASS, Galileo, Beidou and IRNSS) that will be available at the time of the Bepi-Colombo arrival at Mercury (2021), provided that the underlying physics of the turbulent atmosphere and evapotranspiration processes are properly taken into account at such time scales. This implies to do a tomographic image of the troposphere overlying each Deep Space tracking station at time scales of less than 1000 s. For this purpose, we have

  4. ICPP custom dissolver explosion recovery

    International Nuclear Information System (INIS)

    Demmer, R.; Hawk, R.

    1992-01-01

    This report discusses the recovery from the February 9, 1991 small scale explosion in a custom processing dissolver at the Idaho Chemical Processing Plant. Custom processing is a small scale dissolution facility which processes nuclear material in an economical fashion. The material dissolved in this facility was uranium metal, uranium oxides, and uranium/fissium alloy in nitric acid. The paper explained the release of fission material, and the decontamination and recovery of the fuel material. The safety and protection procedures were also discussed. Also described was the chemical analysis which was used to speculate the most probable cause of the explosion. (MB)

  5. Explosions in Landau Vlasov dynamics

    International Nuclear Information System (INIS)

    Suraud, E.; Cussol, D.; Gregoire, C.; Boilley, D.; Pi, M.; Schuck, P.; Remaud, B.; Sebille, F.

    1988-01-01

    A microscopic study of the quasi-fusion/explosion transition is presented in the framework of Landau-Vlasov simulations of intermediate energy heavy-ion collisions (bombarding energies between 10 and 100 MeV/A). A detailed analysis in terms of the Equation of State of the system is performed. In agreement with schematic models we find that the composite nuclear system formed in the collision does explode when it stays long enough in the mechanically unstable region (spinodal region). Quantitative estimates of the explosion threshold are given for central symmetric reactions (Ca+Ca and Ar+Ti). The effect of the nuclear matter compressibility modulus is discussed

  6. System for detecting nuclear explosions

    International Nuclear Information System (INIS)

    Rawls, L.E.

    1978-01-01

    Apparatus for detecting underground nuclear explosions is described that is comprised of an antenna located in the dielectric substance of a deep waveguide in the earth and adapted to detect low frequency electromagnetic waves generated by a nuclear explosion, the deep waveguide comprising the high conductivity upper sedimentary layers of the earth, the dielectric basement rock, and a high conductivity layer of basement rock due to the increased temperature thereof at great depths, and means for receiving the electromagnetic waves detected by said antenna means

  7. Biological consequences of atomic explosions

    International Nuclear Information System (INIS)

    Messerschmidt, O.

    1984-01-01

    After an introductory chapter of the development and properties of nuclear weapons and the events of Hiroshima and Nagasaki, this books shows the effects of atomic explosions for man: effects of the pressure wave, thermal radiation, initial nuclear radiation alone or in conjunction and possible medical help. In addition the less massive damage caused by induced radioactivity and fallout, their prevention resp. treatment and the malignant/nonmalignant late effects are discussed. A further chapter deals with the psychological and epidemiological effects of atomic explosions, the consequences for food and water supply, and the construction of shetters. The last chapter is concerned with the problem of organising medical help. (MG) [de

  8. Delayed signatures of underground nuclear explosions

    Science.gov (United States)

    Carrigan, Charles R.; Sun, Yunwei; Hunter, Steven L.; Ruddle, David G.; Wagoner, Jeffrey L.; Myers, Katherine B. L.; Emer, Dudley F.; Drellack, Sigmund L.; Chipman, Veraun D.

    2016-03-01

    Radionuclide signals from underground nuclear explosions (UNEs) are strongly influenced by the surrounding hydrogeologic regime. One effect of containment is delay of detonation-produced radioxenon reaching the surface as well as lengthening of its period of detectability compared to uncontained explosions. Using a field-scale tracer experiment, we evaluate important transport properties of a former UNE site. We observe the character of signals at the surface due to the migration of gases from the post-detonation chimney under realistic transport conditions. Background radon signals are found to be highly responsive to cavity pressurization suggesting that large local radon anomalies may be an indicator of a clandestine UNE. Computer simulations, using transport properties obtained from the experiment, track radioxenon isotopes in the chimney and their migration to the surface. They show that the chimney surrounded by a fractured containment regime behaves as a leaky chemical reactor regarding its effect on isotopic evolution introducing a dependence on nuclear yield not previously considered. This evolutionary model for radioxenon isotopes is validated by atmospheric observations of radioxenon from a 2013 UNE in the Democratic People’s Republic of Korea (DPRK). Our model produces results similar to isotopic observations with nuclear yields being comparable to seismic estimates.

  9. Hydrodynamic modeling and explosive compaction of ceramics

    International Nuclear Information System (INIS)

    Hoenig, C.; Holt, A.; Finger, M.; Kuhl, W.

    1977-01-01

    High-density ceramics with high-strength microstructure were achieved by explosive compaction. Well-characterized Al 2 O 3 , AlN, and boron powders were explosively compacted in both cylindrical and flat plate geometries. In cylindrical geometries compacted densities between 91 and 98 percent of theoretical were achieved. Microhardness measurements indicated that the strength and integrity of the microstructure were comparable to conventionally fabricated ceramics, even though all samples with densities greater than 90 percent theoretical contained macrocracks. Fractured surfaces evaluated by SEM showed evidence of boundary melting. Equation of state data for porous Al 2 O 3 were used to calculate the irreversible work done on the sample as a function of pressure. This was expressed as a percentage of the total sample which could be melted. Calculations show that very little melting can be expected in samples shocked to less than 3 GPa. Significant melting and grain boundary fusion can be expected in samples shocked to pressures greater than 8 GPa. Hydrodynamic modeling of right cylinder compaction with detonation at one end was attempted by using a two-dimensional computer code. The complications of this analysis led to experiments using plane shock waves. Flat-plate compaction assemblies were designed and analyzed by 2-D hydrodynamic codes. The use of porous shock attenuators was evaluated. Experiments were performed on aluminum oxide powders in plane wave geometry. Microstructure evaluations were made as a function of location in the flat plate samples. 11 figures, 1 table

  10. Performance calculations on the ANFO explosive RX-HD

    Energy Technology Data Exchange (ETDEWEB)

    Souers, P.C.; Larson, D.B.; Tarver, C.M.

    1994-12-31

    This report presents the calculation methods utilized in asessing the detonation performance of the ammonium nitrate-fuel oil (ANFO) utilized in the non-proliferation experiment (NPE) underground explosion at te Nevada Test Site. The composition of the ANFO is discussed.

  11. Historical Survey: German Research on Hydrogen Peroxide/Alcohol Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Parmeter, John E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Discussion of HP/fuel explosives in the scientific literature dates back to at least 1927. A paper was published that year in a German journal entitled On Hydrogen Peroxide Explosives [Bamberger and Nussbaum 1927]. The paper dealt with HP/cotton/Vaseline formulations, specifically HP89/cotton/Vaseline (76/15/9) and (70/8.5/12.5). The authors performed experiments with charge masses of 250-750 g and charge diameters of 35-45 mm. This short paper provides brief discussion on the observed qualitative effects of detonations but does not report detonation velocities.

  12. High-temperature explosive development for geothermal well stimulation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, E.W.; Mars, J.E.; Wang, C.

    1978-03-31

    A two-component, temperature-resistant liquid explosive called HITEX has been developed which is capable of withstanding 561/sup 0/K (550/sup 0/F) for 24 hours in a geothermal environment. The explosive is intended for the stimulation of nonproducing or marginally producing geothermal (hot dry rock, vapor-dominated or hydrothermal) reservoirs by fracturing the strata in the vicinity of a borehole. The explosive is inherently safe because it is mixed below ground downhole from two nondetonable liquid components. Development and safety tests included differential scanning calorimetry, thermal stability, minerals compatibility, drop-weight sensitivity, adiabatic compression, electrostatic discharge sensitivity, friction sensitivity, detonation arrest capability, cook-off tests, detonability at ambient and elevated pressure, detonation velocity and thin film propagation in a wedge.

  13. Oral Trauma and Tooth Avulsion Following Explosion of E-Cigarette.

    Science.gov (United States)

    Rogér, James M; Abayon, Maricelle; Elad, Sharon; Kolokythas, Antonia

    2016-06-01

    Electronic cigarettes (E-cigarettes), or personal vaporizers, were introduced in 2003 and have been available in the United States since 2007. In addition to the health and safety concerns of the aerosol delivery of nicotine through E-cigarettes, during the past 8 years, reports of explosions and fires caused by the E-cigarette devices have led the US Fire Administration to evaluate the safety of these devices. These explosions have been observed frequently enough that the US Department of Transportation has recently banned E-cigarette devices in checked baggage aboard airplanes. This report contributes to existing knowledge about the hazards related to E-cigarettes by describing oral hard and soft tissue injuries from an E-cigarette explosion. Copyright © 2016 The American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  14. Explosion accident at LPG storage in Mexico. Bleve of PEMEX Co

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai Yoshio (The Yasuda Fire and Marine Insurance Co., Ltd., Tokyo, (Japan))

    1989-09-01

    This paper reports the BLEVE (Boiling Expanding Vapor Explosion) which occurred at LPG storage-supply plant of PEMEX Co. (Petroles Mexicanos Co.) in San Juan Ixhuatepec, Mexico on 19th of Nov., 1984. As the actual spot of the explosion is close to residential areas, 50 persons died, 200 was missing, and 723 were injured. Another adjacent LPG storage burned down by the spreading fire, and 200,000 residents retired to safety places. A part of the LPG supply Pipes was destroyed, from where LPG leaked and ignited. During one hour and a half, 15 violent explosions occurred, 9 of which were recorded by the seismometer set up at University of Mexico, about 10km apart. 3 refs., 5 figs.

  15. Millisecond-Period Meltdown Experiments on Prompt - Burst Effects and Molten-Tin-Water Dropping Experiments

    International Nuclear Information System (INIS)

    Wright, R.W.; Coats, R.L.; Schmidt, T.R.; Arakeri, V.H.

    1976-01-01

    The U.S. Nuclear Regulatory Commission has initiated a program of confirmatory research for the safety assessment of LMFBR plants. In the sodium-fuel interactions area, this research includes a series of real-time in-pile experiments on the pressure and work potential of prompt-burst excursions as well as laboratory dropping experiments with molten tin and water. The in-pile experiments are performed by Sandia Laboratories in the Annular Core Pulse Reactor (ACPR), which has a minimum period of 1.3 milliseconds. These single-pin experiments are performed in a piston-loaded, stagnant-sodium autoclave, that is conceptually similar to the one used in the S-11 TREAT test. Unlike the S-11 test, however, realistic radial temperature profiles are obtained in the fuel, the cladding, and the sodium by pre-pulsing the reactor about 1/2 second before the main pulse. A series of preparatory runs have been made with helium-filled capsules and at low energy with sodium-filled capsules. The first significant fuel-coolant interaction run is scheduled for late March 1976. This will be a double-pulsed run at 2700 j/gm UO 2 . A continuing series of experiments is planned with oxide and advanced fuels in both fresh and irradiated form. In molten-tin-water dropping experiments at UCLA, microsecond duration multi-flash photography has been used for event diagnostics. Transition or nucleate boiling was found to trigger energetic interactions or vapor explosions. Temperature stratification in the water was found to reduce the threshold tin temperature necessary to produce vapor explosions below that the predicted by the coolant homogeneous nucleation hypothesis. Interaction zone growth times of a few msec were measured

  16. Surface effects of underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Allen, B.M.; Drellack, S.L. Jr.; Townsend, M.J.

    1997-06-01

    The effects of nuclear explosions have been observed and studied since the first nuclear test (code named Trinity) on July 16, 1945. Since that first detonation, 1,053 nuclear tests have been conducted by the US, most of which were sited underground at the Nevada Test Site (NTS). The effects of underground nuclear explosions (UNEs) on their surroundings have long been the object of much interest and study, especially for containment, engineering, and treaty verification purposes. One aspect of these explosion-induced phenomena is the disruption or alteration of the near-surface environment, also known as surface effects. This report was prepared at the request of the Los Alamos National Laboratory (LANL), to bring together, correlate, and preserve information and techniques used in the recognition and documentation of surface effects of UNEs. This report has several main sections, including pertinent background information (Section 2.0), descriptions of the different types of surface effects (Section 3.0), discussion of their application and limitations (Section 4.0), an extensive bibliography and glossary (Section 6.0 and Appendix A), and procedures used to document geologic surface effects at the NTS (Appendix C). Because a majority of US surface-effects experience is from the NTS, an overview of pertinent NTS-specific information also is provided in Appendix B. It is not within the scope of this report to explore new relationships among test parameters, physiographic setting, and the types or degree of manifestation of surface effects, but rather to compile, summarize, and capture surface-effects observations and interpretations, as well as documentation procedures and the rationale behind them.

  17. Experimental approach to explosive nucleosynthesis

    International Nuclear Information System (INIS)

    Kubono, S.

    1991-07-01

    Recent development of experimental studies on explosive nucleosynthesis, especially the rapid proton process and the primordial nucleosynthesis were discussed with a stress on unstable nuclei. New development in the experimental methods for the nuclear astrophysics is also discussed which use unstable nuclear beams. (author)

  18. Lead-free primary explosives

    Science.gov (United States)

    Huynh, My Hang V.

    2010-06-22

    Lead-free primary explosives of the formula (cat).sub.Y[M.sup.II(T).sub.X(H.sub.2O).sub.6-X].sub.Z, where T is 5-nitrotetrazolate, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  19. Explosive micro-bubble actuator

    NARCIS (Netherlands)

    van den Broek, D.M.; Elwenspoek, Michael Curt

    2007-01-01

    Explosive evaporation occurs when a thin layer of liquid reaches a very high temperature in a very short time. At these temperatures homogeneous nucleation takes place. The nucleated bubbles almost instantly coalesce forming a vapour film followed by rapid growth due to the pressure impulse and

  20. Frictional properties of single crystals HMX, RDX and PETN explosives

    International Nuclear Information System (INIS)

    Wu, Y.Q.; Huang, F.L.

    2010-01-01

    The frictional properties of single crystals of cyclotetramethylene tetranitramine (HMX), cyclotrimethylene trinitramine (RDX) and pentaerythritol tetranitrate (PETN) secondary explosives are examined using a sensitive friction machine. The explosive crystals used for the measurements are at least 3.5 mm wide. The friction coefficients between crystals of the same explosive (i.e., HMX on HMX, etc.), crystals of different explosives (i.e., HMX on RDX, etc.), and each explosive and a well-polished gauge steel surface are determined. The frictional surfaces are also studied under an environmental scanning electron microscope (ESEM) to analyze surface microstructural changes under increasing loading forces. The friction coefficients vary considerably with increasing normal loading forces and are particularly sensitive to slider shapes, crystal roughness and the mechanical properties of both the slider and the sample. With increasing loading forces, most friction experiments show surface damage, consisting of grooves, debris, and nano-particles, on both the slider and sample. In some cases, a strong evidence of a localized molten state is found in the central region of the friction track. Possible mechanisms that affect the friction coefficient are discussed based on microscopic observations.

  1. An experimental study of an explosively driven flat plate launcher

    Science.gov (United States)

    Rae, Philip; Haroz, Erik; Armstrong, Chris; Perry, Lee; M Division Team

    2017-06-01

    For some upcoming experiments it is desired to impact a large explosive assembly with one or more moderate diameter flat metal plates traveling at high velocity (2-3 km s-1). The time of arrival of these plates will need to carefully controlled and delayed (i.e. the time(s) of arrival known to approximately a microsecond). For this reason, producing a flyer plate from more traditional gun assemblies is not possible. Previous researchers have demonstrated the ability to throw reasonably flat metal flyers from the so-called Forest flyer geometry. The defining characteristics of this design are a carefully controlled reduction in explosive area from a larger explosive plane-wave-lens and booster pad to a smaller flyer plate to improve the planarity of the drive available and an air gap between the explosive booster and the plate to reduce the peak tensile stresses generated in the plate to suppress spalling. This experimental series comprised a number of different design variants and plate and explosive drive materials. The aim was to calibrate a predictive computational modeling capability on this kind of system in preparation for later more radical design ideas best tested in a computer before undertaking the expensive business of construction.

  2. Detection of chemical explosives using multiple photon signatures

    International Nuclear Information System (INIS)

    Loschke, K.W.; Dunn, W.L.

    2008-01-01

    Full text: A template-matching procedure to aid in rapid detection of improvised explosive devices (IEDs) is being investigated. Multiple photon-scattered and photon-induced positron annihilation radiation responses are being used as part of a photon-neutron signature-based radiation scanning (SBRS) approach (see companion reference for description of the neutron component), in an attempt to detect chemical explosives at safe standoff distances. Many past and present photon interrogation methods are based on imaging. Imaging techniques seek to determine at high special resolution the internal structure of a target of interest. Our technique simply seeks to determine if an unknown target contains a detectable amount of chemical explosives by comparing multiple responses (signatures) that depend on both density and composition of portions of a target. In the photon component, beams of photons are used to create back-streaming signatures, which are dependent on the density and composition of part of the target being interrogated. These signatures are compared to templates, which are collections of the same signatures if the interrogated volume contained a significant amount of explosives. The signature analysis produces a figure-of-merit and a standard deviation of the figure-of-merit. These two metrics are used to filter safe from dangerous targets. Experiments have been conducted that show that explosive surrogates (fertilizers) can be distinguished from several inert materials using these photon signatures, demonstrating that these signatures can be used effectively to help IEDs

  3. Explosion hazard in liquid nitrogen cooled fusion systems

    International Nuclear Information System (INIS)

    Brereton, S.J.

    1988-01-01

    The explosion hazard associated with the use of liquid nitrogen in a radiation environment in fusion facilities has been investigated. The principal product of irradiating liquid nitrogen is thought to be ozone, resulting from the action of radiation on oxygen impurity. Ozone is a very unstable material, and explosions may occur as it rapidly decomposes to oxygen. Occurrences of this problem in irradiated liquid nitrogen systems are reviewed. An empirical expression, from early experiments, for the yield of ozone in liquid nitrogen-oxygen mixtures exposed to gamma radiation is employed to assess the degree of ozone explosion hazard expected at fusion facilities. The problem is investigated for the Compact Ignition Tokamak (CIT) as a particular example. 16 refs., 5 figs., 1 tab

  4. Nuclear system vaporization

    International Nuclear Information System (INIS)

    Bougault, R.; Brou, R.; Colin, J.; Cussol, D.; Durand, D.; Le Brun, C.; Lecolley, J.F.; Lopez, O.; Louvel, M.; Nakagawa, T.; Peter, J.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.; Vient, E.; Yuasa-Nakagawa, K.; Wieloch, A.

    1998-01-01

    A particular case of the hot nuclei de-excitation is the total nuclear dislocation into light particles (n, p, d, t, 3 He and α). Such events were first observed at bombarding energies lower than 100 MeV/nucleon due to high detection performances of the INDRA multidetector. The light system Ar + Ni was studied at several bombarding energies ranging from 32 to 95 MeV/nucleon. The events associated to a total vaporization of the system occur above the energy threshold of ∼ 50 MeV/nucleon. A study of the form of these events shows that we have essentially two sources. The excitation energy of these sources may be determined by means of the kinematic properties of their de-excitation products. A preliminary study results in excitation energy values of the order 10 - 14 MeV/nucleon. The theoretical calculation based on a statistical model modified to take into account high excitation energies and excited levels in the lightest nuclei predicts that the vaporization of the two partner nuclei in the Ar + Ni system takes place when the excitation energy exceeds 12 MeV/nucleon what is qualitatively in agreement with the values deduced from calorimetric analysis

  5. Explosives and chemical warfare agents - detection and analysis with PTR-MS

    Energy Technology Data Exchange (ETDEWEB)

    Sulzer, Philipp; Juerschik, Simone; Jaksch, Stefan; Jordan, Alfons; Hanel, Gernot; Hartungen, Eugen; Seehauser, Hans; Maerk, Lukas; Haidacher, Stefan; Schottkowsky, Ralf [IONICON Analytik GmbH, Innsbruck (Austria); Petersson, Fredrik [Institut fuer Ionenphysik und Angewandte Physik, Leopold-Franzens Universitaet Innsbruck (Austria); Maerk, Tilmann [IONICON Analytik GmbH, Innsbruck (Austria); Institut fuer Ionenphysik und Angewandte Physik, Leopold-Franzens Universitaet Innsbruck (Austria)

    2010-07-01

    We utilized a recently developed high sensitivity PTR-MS instrument equipped with a high resolution time-of-flight mass analyzer for detailed investigations on explosives and chemical warfare agents (CWAs). We show that with this so called PTR-TOF 8000 it is possible to identify solid explosives (RDX, TNT, HMX, PETN and Semtex A) by analyzing the headspace above small quantities of samples at room temperature and from trace quantities not visible to the naked eye placed on surfaces. As the mentioned solid explosives possess very low vapor pressures, the main challenge for detecting them in the gas phase is to provide an instrument with a sufficient sensitivity. CWAs on the other side have very high vapor pressures but are difficult to identify unambiguously as their nominal molecular masses are usually comparably small and therefore hard to distinguish from harmless everyday-compounds (e.g. mustard gas: 159 g/mol). In the present work we demonstrate that we can detect a broad range of dangerous substances, ranging from the CWA mustard gas to the explosive HMX.

  6. Eulerian finite-difference calculations of explosions in partially water-filled overstrong cylindrical containment vessels

    International Nuclear Information System (INIS)

    Thompson, S.L.; Herrmann, W.

    1977-01-01

    Calculations, using the two-dimensional Eulerian finite-difference code CSQ, were performed for the problem of a small spherical high-explosive charge detonated in a closed heavy-walled cylindrical container partially filled with water. Data from corresponding experiments, specifically performed to validate codes used for hypothetical core disruptive accidents of liquid metal fast breeder reactors, are available in the literature. The calculations were performed specifically to test whether Eulerian methods could handle this type of problem, to determine whether water cavitation, which plays a large role in the loadings on the roof of the containment vessel, could be described adequately by an equilibrium liquid-vapor mixed phase model, and to investigate the trade-off between accuracy and cost of the calculations by using different sizes of computational meshes. Comparison of the experimental and computational data shows that the Eulerian method can handle the problem with ease, giving good predictions of wall and floor loadings. While roof loadings are qualitatively correct, peak impulse appears to be affected by numerical resolution and is underestimated somewhat

  7. Behavior of explosion debris clouds

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    In the normal course of events the behavior of debris clouds created by explosions will be of little concern to the atomic energy industry. However, two situations, one of them actual and one postulated, exist where the rise and spread of explosion clouds can affect site operations. The actual occurrence would be the detonation of nuclear weapons and the resultant release and transport of radioactive debris across the various atomic energy installations. Although the activity of the diffusing cloud is not of biological concern, it may still be sufficiently above background to play havoc with the normal readings of sensitive monitoring instruments. If it were not known that these anomalous readings resulted from explosion debris, considerable time and expense might be required for on-site testing and tracing. Fortunately it is usually possible, with the use of meteorological data and forecasts, to predict when individual sites are affected by nuclear weapon debris effects. The formation rise, and diffusion of weapon clouds will be discussed. The explosion of an atomic reactor is the postulated situation. It is common practice in reactor hazard analysis to assume a combination of circumstances which might result in a nuclear incident with a release of material to the atmosphere. It is not within the scope of this report to examine the manifold plausibilities that might lead to an explosion or the possible methods of release of gaseous and/or particulates from such an occurrence. However, if the information of a cloud is assumed and some idea of its energy content is obtainable, estimates of the cloud behavior in the atmosphere can be made

  8. Evaporation monitoring and composition control of alloy systems with widely differing vapor pressures

    International Nuclear Information System (INIS)

    Anklam, T.M.; Berzins, L.V.; Braun, D.G.; Haynam, C.; McClelland, M.A.; Meier, T.

    1994-10-01

    Lawrence Livermore National Laboratory is developing sensors and controls to improve and extend electron beam materials processing technology to alloy systems with constituents of widely varying vapor pressure. The approach under development involves using tunable lasers to measure the density and composition of the vapor plume. A laser based vaporizer control system for vaporization of a uranium-iron alloy has been previously demonstrated in multi-hundred hour, high rate vaporization experiments at LLNL. This paper reviews the design and performance of the uranium vaporization sensor and control system and discusses the extension of the technology to monitoring of uranium vaporization. Data is presented from an experiment in which titanium wire was fed into a molten niobium pool. Laser data is compared to deposited film composition and film cross sections. Finally, the potential for using this technique for composition control in melting applications is discussed

  9. Ideas for peaceful nuclear explosions in USSR

    International Nuclear Information System (INIS)

    1970-01-01

    Three papers prepared in USSR have been made available to the Agency for circulation among Member States. One examines radioactive contamination and methods for predicting it, of natural environments during underground explosions. Another deals with the mechanical effect of underground explosions. The third, which forms the basis of this article, reviews possible applications of peaceful nuclear explosions in the Soviet economy. (author)

  10. Gas explosion in domestic buildings. The vented gas explosion[sub][/sub

    Directory of Open Access Journals (Sweden)

    Tadeusz Chyży

    2014-08-01

    Full Text Available In this paper, the basic information, related to the so-called vented gas explosion, has been presented. The vented explosion it is an explosion, during which the destruction of the weakest elements of the structure occurs. Through the resulting holes (decompressing surfaces can flow both combustion products and non-burned gas mixture. In consequence, reduction of the maximum explosion pressure[i] P[sub]red [/sub][/i] may be significant. Often, a gas explosion occurs inside residential buildings. In this case, natural vents are window and door openings.[b]Keywords[/b]: gas, explosion, combustion, explosion vents

  11. Dwell-time effect on the synthesis of a nano-structured material in water by using Ni wire explosion

    International Nuclear Information System (INIS)

    Eom, Gyu Sub; Kwon, Hyeok Jung; Cho, Yong Sub; Paek, Kwang Hyun; Joo, Won Tae

    2014-01-01

    Nickel nano-structured materials are synthesized by using a wire explosion in water. Based on an analysis of each step of the wire explosion, we propose insufficient energy deposition before a plasma restrike as the cause for the inclusion of coarse particles in the wire-explosion product. We confirmed that more energy, in excess of 30%, could be deposited by increasing the dwell time, which resulted from a compression of vapor by the surrounding water and from suppression of plasma restrikes. Because of an increased energy loss into the surrounding water, the specific energy increased by two-fold compared to a gas atmosphere. The synthesized nano-structured nickel showed a uniform particle size of 20 nm with a few coarse particles that were mainly metallic nickel with a little oxide and hydroxide phases. The possibility for large-volume production through a continuous explosion of 300 shots was confirmed.

  12. Seismic Methods of Identifying Explosions and Estimating Their Yield

    Science.gov (United States)

    Walter, W. R.; Ford, S. R.; Pasyanos, M.; Pyle, M. L.; Myers, S. C.; Mellors, R. J.; Pitarka, A.; Rodgers, A. J.; Hauk, T. F.

    2014-12-01

    Seismology plays a key national security role in detecting, locating, identifying and determining the yield of explosions from a variety of causes, including accidents, terrorist attacks and nuclear testing treaty violations (e.g. Koper et al., 2003, 1999; Walter et al. 1995). A collection of mainly empirical forensic techniques has been successfully developed over many years to obtain source information on explosions from their seismic signatures (e.g. Bowers and Selby, 2009). However a lesson from the three DPRK declared nuclear explosions since 2006, is that our historic collection of data may not be representative of future nuclear test signatures (e.g. Selby et al., 2012). To have confidence in identifying future explosions amongst the background of other seismic signals, and accurately estimate their yield, we need to put our empirical methods on a firmer physical footing. Goals of current research are to improve our physical understanding of the mechanisms of explosion generation of S- and surface-waves, and to advance our ability to numerically model and predict them. As part of that process we are re-examining regional seismic data from a variety of nuclear test sites including the DPRK and the former Nevada Test Site (now the Nevada National Security Site (NNSS)). Newer relative location and amplitude techniques can be employed to better quantify differences between explosions and used to understand those differences in term of depth, media and other properties. We are also making use of the Source Physics Experiments (SPE) at NNSS. The SPE chemical explosions are explicitly designed to improve our understanding of emplacement and source material effects on the generation of shear and surface waves (e.g. Snelson et al., 2013). Finally we are also exploring the value of combining seismic information with other technologies including acoustic and InSAR techniques to better understand the source characteristics. Our goal is to improve our explosion models

  13. The Ranchero explosive pulsed power system

    International Nuclear Information System (INIS)

    Goforth, J.H.; Atchison, W.L.; Bartram, D.E.

    1997-01-01

    The authors are currently developing a high explosive pulsed power system concept that they call Ranchero. Ranchero systems consist of series-parallel combinations of simultaneously initiated coaxial magnetic flux compression generators, and are intended to operate in the range from 50 MA to a few hundred MA currents. One example of a Ranchero system is shown here. The coaxial modules lend themselves to extracting the current output either from one end or along the generator midplane. They have previously published design considerations related to the different module configurations, and in this paper they concentrate on the system that they will use for their first imploding liner tests. A single module with end output. The module is 1.4-m long and expands the armature by a factor of two to reach the 30-cm OD stator. The first heavy liner implosion experiments will be conducted in the range of 40--50 MA currents. Electrical tests, to date, have employed high explosive (HE) charges 43-cm long. They have performed tests and related 1D MHD calculations at the 45-MA current level with small loads. From these results, they determine that they can deliver currents of approximately 50 MA to loads of 8 nH

  14. The Development of Explosive Metalworking in Poland

    Directory of Open Access Journals (Sweden)

    Babul W.

    2014-10-01

    Full Text Available The author coordinated the research in Poland by the collaboration with civil and military scientific and research centres. In result they elaborated detonation process of spraying coats designed and constructed stands equipped with detonative devices, they also elaborated the techniques of basic coating parameter measurement and built devices for commercial and scientific services. In the research the author's achievements within the range of explosive welding have been used. The experience of the scientific teams was very effective. It was observed that many phenomena that take place in the processes of detonative layer coating and explosive welding are the same. In order to obtain a required connection the plastic strain of the connected material surfaces has to be achieved and cumulative flows have to be formed. There are a similar range of the connecting process conditions and the mechanisms of plastic strain. The highest connection strength is obtained when an intermediate zone is formed. The zone has to be composed of the two connected materials. The intermediate layer is formed as a result of mechanical alloying of the materials due to large plastic strain. The plastic strain leads to forming meta-stable phases that have properties of pseudo solid solution, chemical compounds, intermetallic phases and fragmentation corresponding to nanomaterials and amorphous states.

  15. Chemicapacitive microsensors for detection of explosives and TICs

    Science.gov (United States)

    Patel, Sanjay V.; Hobson, Stephen T.; Cemalovic, Sabina; Mlsna, Todd E.

    2005-10-01

    Seacoast Science develops chemical sensors that use polymer-coated micromachined capacitors to measure the dielectric permittivity of an array of selectively absorbing materials. We present recent results demonstrating the sensor technology's capability to detect components in explosives and toxic industrial chemicals. These target chemicals are detected with functionalized polymers or network materials, chosen for their ability to adsorb chemicals. When exposed to vapors or gases, the permittivity of these sorbent materials changes depending on the strength of the vapor-sorbent interaction. Sensor arrays made of ten microcapacitors on a single chip have been previously shown to detect vapors of organic compounds (chemical warfare agents, industrial solvents, fuels) and inorganic gases (SO2, CO2, NO2). Two silicon microcapacitor structures were used, one with parallel electrode plates and the other with interdigitated "finger-like" electrodes. The parallel-plates were approximately 300 μm wide and separated by 750 nm. The interdigitated electrodes were approximately 400 μm long and were elevated above the substrate to provide faster vapor access. Eight to sixteen of these capacitors are fabricated on chips that are 5 x 2 mm and are packaged in less than 50 cm3 with supporting electronics and batteries, all weighing less than 500 grams. The capacitors can be individually coated with different materials creating a small electronic nose that produces different selectivity patterns in response to different chemicals. The resulting system's compact size, low-power consumption and low manufacturing costs make the technology ideal for integration into various systems for numerous applications.

  16. Some ecological aspects of the using nucleus explosions in peace purpose

    International Nuclear Information System (INIS)

    Kalinovskij, A.K.; Krasnov, V.A.; Pazukhin, Eh.M.

    2010-01-01

    This paper presents a brief review of published data about radioactive contamination of environment after carried out underground nuclear explosions for peaceful purposes with reason to use the accumulated experience at liquidation consequences after accident on ChNPP.

  17. Chemical vapor composites (CVC)

    International Nuclear Information System (INIS)

    Reagan, P.

    1993-01-01

    The Chemical Vapor Composite, CVC trademark , process fabricates composite material by simply mixing particles (powders and or fibers) with CVD reactants which are transported and co-deposited on a hot substrate. A key feature of the CVC process is the control provided by varing the density, geometry (aspect ratio) and composition of the entrained particles in the matrix material, during deposition. The process can fabricate composite components to net shape (± 0.013 mm) on a machined substrate in a single step. The microstructure of the deposit is described and several examples of different types of particles in the matrix are illustrated. Mechanical properties of SiC composite material fabricated with SiC powder and fiber will be presented. Several examples of low cost ceramic composite products will be shown. (orig.)

  18. Iron bromide vapor laser

    Science.gov (United States)

    Sukhanov, V. B.; Shiyanov, D. V.; Trigub, M. V.; Dimaki, V. A.; Evtushenko, G. S.

    2016-03-01

    We have studied the characteristics of a pulsed gas-discharge laser on iron bromide vapor generating radiation with a wavelength of 452.9 nm at a pulse repetition frequency (PRF) of 5-30 kHz. The maximum output power amounted to 10 mW at a PRF within 5-15 kHz for a voltage of 20-25 kV applied to electrodes of the discharge tube. Addition of HBr to the medium produced leveling of the radial profile of emission. Initial weak lasing at a wavelength of 868.9 nm was observed for the first time, which ceased with buildup of the main 452.9-nm line.

  19. Reduction of radioactivity produced by nuclear explosives

    Energy Technology Data Exchange (ETDEWEB)

    Lessler, Richard M [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-15

    Four main sources contribute to the radioactivity produced by a nuclear explosive: 1. Fission products from the nuclear explosive, 2. Fusion products from the nuclear explosive, 3. Induced radioactivity in the nuclear explosive, 4. Induced radioactivity in the environment. This paper will summarize some of the work done at the Lawrence Radiation Laboratory at Livermore to reduce the radioactivity from these sources to levels acceptable for peaceful applications. Although it is theoretically possible to have no radioactivity produced by nuclear explosives, this goal has not been achieved.

  20. Numerical simulation of vapor film collapse behavior on high-temperature droplet surface with three-dimensional lattice gas cellular automata

    International Nuclear Information System (INIS)

    Tochio, Daisuke; Abe, Yutaka; Matsukuma, Yosuke

    2008-01-01

    It is pointed out that a vapor film on a premixed high-temperature droplet surface is needed to be collapsed to trigger vapor explosion. Thus, it is important to clarify the micromechanism of vapor film collapse behavior for the occurrence of vapor explosion. In a previous study, it is suggested experimentally that vapor film collapse behavior is dominated by phase change phenomena rather than by the surrounding fluid motion. In the present study, vapor film collapse behavior is investigated to clarify the dominant factor of vapor film collapse behavior with lattice gas automata of three-dimensional immiscible lattice gas model (3-D ILG model). First, in order to represent the boiling and phase change phenomena, the thermal model of a heat wall model and a phase change model is newly constructed. Next, the numerical simulation of vapor film collapse behavior is performed with and without the phase change effect. As a result, the computational result with the phase change effect is observed to be almost same as the experimental result. It can be considered that vapor film collapse behavior is dominated by phase change phenomena. (author)

  1. Vapor-droplet flow equations

    International Nuclear Information System (INIS)

    Crowe, C.T.

    1975-01-01

    General features of a vapor-droplet flow are discussed and the equations expressing the conservation of mass, momentum, and energy for the vapor, liquid, and mixture using the control volume approach are derived. The phenomenological laws describing the exchange of mass, momentum, and energy between phases are also reviewed. The results have application to development of water-dominated geothermal resources

  2. Water containing explosive for big diameter use. [Slurry of ammonium nitrate and monomethyl lamine

    Energy Technology Data Exchange (ETDEWEB)

    Sunakawa, Tomoji; Fujita, Koichi; Kodama, Taro; Suzuki, Masahiro; Ono, Naoki

    1988-05-11

    This is a report concerning the design and experiment of water containing explosive which can be used as a substitute of ANFO. As the water containing explosive, slurry type was taken which consists of ammonium nitrate and monomethyl amine as main components and density of which was more than 1.2, explosion speed 4880 m/s, F value 7790 atm*L/Kg. Experiments were conducted for variuous loading length. From the result, it was recognized that at least 4.5 m of loading length was neccessary for achieving better result than the case whlen only ANFO was used. (1 fig, 1 tab)

  3. Liquid nitrogen - water interaction experiments for fusion reactor accident scenarios

    International Nuclear Information System (INIS)

    Duckworth, R.; Murphy, J.; Pfotenhauer, J.; Corradini, M.

    2001-01-01

    With the implementation of superconducting magnets in fusion reactors, the possibility exists for the interaction between water and cryogenic systems. The interaction between liquid nitrogen and water was investigated experimentally and numerically. The rate of pressurization and peak pressure were found to be driven thermodynamically by the expansion of the water and the boil-off of the liquid nitrogen and did not have a vapor explosion nature. Since the peak pressure was small in comparison to previous work with stratified geometries, the role of the geometry of the interacting fluids has been shown to be significant. Comparisons of the peak pressure and the rate of pressurization with respect to the ratio of the liquid nitrogen mass to water mass reveal no functional dependence as was observed in the liquid helium-water experiments. A simple thermodynamic model provides a fairly good description of the pressure rise data. From the data, the model will allow one to extract the interaction area of the water. As with previous liquid helium-water interaction experiments, more extensive investigation of the mass ratio and interaction geometry is needed to define boundaries between explosive and non-explosive conditions. (authors)

  4. Spot test kit for explosives detection

    Science.gov (United States)

    Pagoria, Philip F; Whipple, Richard E; Nunes, Peter J; Eckels, Joel Del; Reynolds, John G; Miles, Robin R; Chiarappa-Zucca, Marina L

    2014-03-11

    An explosion tester system comprising a body, a lateral flow membrane swab unit adapted to be removeably connected to the body, a first explosives detecting reagent, a first reagent holder and dispenser operatively connected to the body, the first reagent holder and dispenser containing the first explosives detecting reagent and positioned to deliver the first explosives detecting reagent to the lateral flow membrane swab unit when the lateral flow membrane swab unit is connected to the body, a second explosives detecting reagent, and a second reagent holder and dispenser operatively connected to the body, the second reagent holder and dispenser containing the second explosives detecting reagent and positioned to deliver the second explosives detecting reagent to the lateral flow membrane swab unit when the lateral flow membrane swab unit is connected to the body.

  5. Sensitivity to friction for primary explosives.

    Science.gov (United States)

    Matyáš, Robert; Šelešovský, Jakub; Musil, Tomáš

    2012-04-30

    The sensitivity to friction for a selection of primary explosives has been studied using a small BAM friction apparatus. The probit analysis was used for the construction of a sensitivity curve for each primary explosive tested. Two groups of primary explosives were chosen for measurement (a) the most commonly used industrially produced primary explosives (e.g. lead azide, tetrazene, dinol, lead styphnate) and (b) the most produced improvised primary explosives (e.g. triacetone triperoxide, hexamethylenetriperoxide diamine, mercury fulminate, acetylides of heavy metals). A knowledge of friction sensitivity is very important for determining manipulation safety for primary explosives. All the primary explosives tested were carefully characterised (synthesis procedure, shape and size of crystals). The sensitivity curves obtained represent a unique set of data, which cannot be found anywhere else in the available literature. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Problems in the theory of point explosions

    Science.gov (United States)

    Korobeinikov, V. P.

    The book is concerned with the development of the theory of point explosions, which is relevant to the study of such phenomena as the initiation of detonation, high-power explosions, electric discharges, cosmic explosions, laser blasts, and hypersonic aerodynamics. The discussion covers the principal equations and the statement of problems; linearized non-self-similar one-dimensional problems; spherical, cylindrical, and plane explosions with allowance for counterpressure under conditions of constant initial density; explosions in a combustible mixture of gases; and point explosions in inhomogeneous media with nonsymmetric energy release. Attention is also given to point explosions in an electrically conducting gas with allowance for the effect of the magnetic field and to the propagation of perturbations from solar flares.

  7. Ex-Vessel Steam Explosion Analysis of Central Melt Pour Scenario

    International Nuclear Information System (INIS)

    Ursic, M.; Leskovar, M.

    2008-01-01

    An ex-vessel steam explosion may develop during a severe reactor accident when the reactor vessel fails and the molten core interacts with the coolant in the reactor cavity. At this process part of the corium energy is intensively transferred to water in a very short time scale. The water vaporizes at high pressure and expands, doing work on its surrounding. Although the steam explosion has probably a low probability of occurrence, it is an important nuclear safety issue in case of a severe reactor accident. Namely, the formed very high pressure region induces dynamic loadings on the surrounding structures that may potentially lead to an early release of the radioactive material into the environment. Although the steam explosion events have being studied for several years, the level of the process and consequences understanding is still not adequate. To increase the level of confidence the OECD programme SERENA (Steam Explosion REsolution for Nuclear Applications) was established in 2002. The objectives of the program were to evaluate capabilities of the current generation of the FCI (Fuel-Coolant Interaction) computer codes in predicting the steam explosion induced loads, identifying key FCI phenomena and associated uncertainties impacting the predictability of the steam explosion energetics in the reactor situations and proposing confirmatory research to reduce the uncertainties to acceptable levels for the steam explosion risk assessment. To get a better insight into the most challenging ex-vessel steam explosions, analyses for different locations of the melt release, the cavity water sub-cooling, the primary system pressure overpressure and the triggering time were preformed for a typical pressurized water reactor cavity. The results of some scenarios revealed that significantly higher pressure loads are predicted than obtained in the OECD programme SERENA Phase 1. Among the performed analyses for the central melt pour scenarios, the maximum pressure loads were

  8. Vapor pressure and enthalpy of vaporization of aliphatic propanediamines

    International Nuclear Information System (INIS)

    Verevkin, Sergey P.; Chernyak, Yury

    2012-01-01

    Highlights: ► We measured vapor pressure of four aliphatic 1,3-diamines. ► Vaporization enthalpies at 298 K were derived. ► We examined consistency of new and available data in the literature. ► A group-contribution method for prediction was developed. - Abstract: Vapor pressures of four aliphatic propanediamines including N-methyl-1,3-propanediamine (MPDA), N,N-dimethyl-1,3-propanediamine (DMPDA), N,N-diethyl-1,3-propanediamine (DEPDA) and N,N,N′,N′-tetramethyl-1,3-propanediamine (4MPDA) were measured using the transpiration method. The vapor pressures developed in this work and reported in the literature were used to derive molar enthalpy of vaporization values at the reference temperature 298.15 K. An internal consistency check of the enthalpy of vaporization was performed for the aliphatic propanediamines studied in this work. A group-contribution method was developed for the validation and prediction vaporization enthalpies of amines and diamines.

  9. Seismic verification of underground explosions

    International Nuclear Information System (INIS)

    Glenn, L.A.

    1985-06-01

    The first nuclear test agreement, the test moratorium, was made in 1958 and lasted until the Soviet Union unilaterally resumed testing in the atmosphere in 1961. It was followed by the Limited Test Ban Treaty of 1963, which prohibited nuclear tests in the atmosphere, in outer space, and underwater. In 1974 the Threshold Test Ban Treaty (TTBT) was signed, limiting underground tests after March 1976 to a maximum yield of 250 kt. The TTBT was followed by a treaty limiting peaceful nuclear explosions and both the United States and the Soviet Union claim to be abiding by the 150-kt yield limit. A comprehensive test ban treaty (CTBT), prohibiting all testing of nuclear weapons, has also been discussed. However, a verifiable CTBT is a contradiction in terms. No monitoring technology can offer absolute assurance that very-low-yield illicit explosions have not occurred. The verification process, evasion opportunities, and cavity decoupling are discussed in this paper

  10. Honey bees (Apis mellifera) as explosives detectors: exploring proboscis extension reflex conditioned response to trinitrotolulene (TNT)

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-mccabe, Kirsten J [Los Alamos National Laboratory; Wingo, Robert M [Los Alamos National Laboratory; Haarmann, Timothy K [Los Alamos National Laboratory

    2008-01-01

    We examined honey bee's associative learning response to conditioning with trinitrotolulene (TNT) vapor concentrations generated at three temperatures and their ability to be reconditioned after a 24 h period. We used classical conditioning of the proboscis extension (PER) in honey bees using TNT vapors as the conditioned stimulus and sucrose as the unconditioned stimulus. We conducted fifteen experimental trials with an explosives vapor generator set at 43 C, 25 C and 5 C, producing three concentrations of explosives (1070 ppt, 57 ppt, and 11 ppt). Our objective was to test the honey bee's ability to exhibit a conditioned response to TNT vapors at all three concentrations by comparing the mean percentage of honey bees successfully exhibiting a conditioned response within each temperature group. Furthermore, we conducted eight experimental trials to test the honey bee's ability to retain their ability to exhibit a conditioned response to TNT after 24h period by comparing the mean percentage of honey bees with a conditioned response TNT on the first day compared to the percentage of honey bees with a conditioned response to TNT on the second day. Results indicate that there was no significant difference between the mean percentage of honey bees with a conditioned response to TNT vapors between three temperature groups. There was a significant difference between the percentage of honey bees exhibiting conditioned response on the first day of training compared to the percentage of honey bees exhibiting conditioned response 24 h after training. Our experimental results indicate that honey bees can be trained to exhibit a conditioned response to a range of TNT concentrations via PER However, it appears that the honey bee's ability to retain the conditioned response to TNT vapors after 24h significantly decreases.

  11. A Citizen's Guide to Vapor Intrusion Mitigation

    Science.gov (United States)

    This guide describes how vapor intrusion is the movement of chemical vapors from contaminated soil and groundwater into nearby buildings.Vapors primarily enter through openings in the building foundation or basement walls.

  12. Vapor pressure measured with inflatable plastic bag

    Science.gov (United States)

    1965-01-01

    Deflated plastic bag in a vacuum chamber measures initial low vapor pressures of materials. The bag captures the test sample vapors and visual observation of the vapor-inflated bag under increasing external pressures yields pertinent data.

  13. Emplacement and stemming of nuclear explosives for Plowshare applications

    International Nuclear Information System (INIS)

    Cramer, J.L.

    1970-01-01

    This paper will discuss the various methods used for emplacement and design considerations that must be taken into account when the emplacement and stemming method is selected. The step-by-step field procedure will not be discussed in this paper. The task of emplacing and stemming the nuclear explosive is common to all Plowshare experiments today. All present-day applications of a nuclear explosive for Plowshare experiments require that the detonation take place some distance below the surface of the ground. This is normally done by lowering the explosive into an emplacement hole to a desired depth and then backfilling the hole with a suitable stemming material. At first glance it scenes like a very straightforward, simple task to perform. It would appear to be a task that could become a standard procedure for all experiments; however, this is not the case. In actuality, the emplacement and stemming of a nuclear explosive must almost be a custom design. It varies with the application of the experiment, i.e., cratering or underground engineering. It also varies with the condition of the hole, the available equipment to do the job, the actual purpose of the stemming, possible postshot reentry, hydrology, geology, and future production. A very important item that must always be considered is the protection of the firing and signal cables during the downhole and stemming operation. Each of these things must be considered; ignoring any one of them could jeopardize one of the objectives of the experiment or perhaps even the experiment itself. It should be emphasized that for a multiple-shot program such as would be used to develop a gas field where the geology, depths of burial etc. are the same, the emplacement and stemming operation would be standardized, as would all other parts of the program. However, for individual experiments in totally different areas, complete standardization of the emplacement and stemming is impossible

  14. Emplacement and stemming of nuclear explosives for Plowshare applications

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, J L [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-15

    This paper will discuss the various methods used for emplacement and design considerations that must be taken into account when the emplacement and stemming method is selected. The step-by-step field procedure will not be discussed in this paper. The task of emplacing and stemming the nuclear explosive is common to all Plowshare experiments today. All present-day applications of a nuclear explosive for Plowshare experiments require that the detonation take place some distance below the surface of the ground. This is normally done by lowering the explosive into an emplacement hole to a desired depth and then backfilling the hole with a suitable stemming material. At first glance it scenes like a very straightforward, simple task to perform. It would appear to be a task that could become a standard procedure for all experiments; however, this is not the case. In actuality, the emplacement and stemming of a nuclear explosive must almost be a custom design. It varies with the application of the experiment, i.e., cratering or underground engineering. It also varies with the condition of the hole, the available equipment to do the job, the actual purpose of the stemming, possible postshot reentry, hydrology, geology, and future production. A very important item that must always be considered is the protection of the firing and signal cables during the downhole and stemming operation. Each of these things must be considered; ignoring any one of them could jeopardize one of the objectives of the experiment or perhaps even the experiment itself. It should be emphasized that for a multiple-shot program such as would be used to develop a gas field where the geology, depths of burial etc. are the same, the emplacement and stemming operation would be standardized, as would all other parts of the program. However, for individual experiments in totally different areas, complete standardization of the emplacement and stemming is impossible.

  15. Bipolar explosion models for hypernovae

    International Nuclear Information System (INIS)

    Maeda, Keiichi; Nomoto, Ken'ichi

    2003-01-01

    Bipolar explosion models for hypernovae (very energetic supernovae) are presented. These models provide a favorable situation to explain some unexpected features in observations of hypernovae, e.g., high velocity matter dominated by Fe and low velocity matter dominated by O. The overall abundance of these models gives a good fit, at least qualitatively, to abundances in extremely metal-poor stars. We suggest hypernovae be driven by bipolar jets and contribute significantly to the early Galactic chemical evolution

  16. Mass extinctions and supernova explosions

    OpenAIRE

    Korschinek, Gunther

    2016-01-01

    A nearby supernova (SN) explosion could have negatively influenced life on Earth, maybe even been responsible for mass extinctions. Mass extinction poses a significant extinction of numerous species on Earth, as recorded in the paleontologic, paleoclimatic, and geological record of our planet. Depending on the distance between the Sun and the SN, different types of threats have to be considered, such as ozone depletion on Earth, causing increased exposure to the Sun's ultraviolet radiation, o...

  17. Investigation on the Interface Morphologies of Explosive Welding of Inconel 625 to Steel A516 Plates

    Science.gov (United States)

    Mousavi, S. A. A. Akbari; Zareie, H. R.

    2011-01-01

    The purpose of this study is to produce composite plates by explosive cladding process. This is a process in which the controlled energy of explosives is used to create a metallic bond between two similar or dissimilar materials. The welding conditions were tailored through parallel geometry route with different operational parameters. In this investigation, a two-pronged study was adopted to establish the conditions required for producing successful solid state welding: (a) Analytical calculations to determine the weldability domain or welding window; (b) Metallurgical investigations of explosive welding experiments carried out under different explosive ratios to produce both wavy and straight interfaces. The analytical calculations confirm the experimental results. Optical microscopy studies show that a transition from a smooth to wavy interface occurs with an increase in explosive ratio. SEM studies show that the interface was outlined by characteristic sharp transition between two materials.

  18. Use of chemical explosives for emergency solar flare shelter construction and other excavations on the Martian surface

    International Nuclear Information System (INIS)

    Dick, R.D.; Blacic, J.D.; Pettitt, D.R.

    1985-01-01

    The necessity to shelter people on the Martian surface from solar flare particles at short notice and the need for long-term habitats with thick cosmic ray shielding suggests that explosives could be used effectively for excavation of such structures. Modern insensitive high explosives are safe, efficient, and reliable for rock breakage and excavation. Extensive Earth-bound experience leads us to propose several strategies for explosively-constructed shelters based on tunneling, cratering, and rock casting techniques

  19. Performance properties of commercial explosives

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J.N.; Mader, C.L.; Goldstein, S.

    1983-01-01

    The aquarium test is a proven means of obtaining nonidial performance property data for commercial blasting agents. Optical data on the detonation velocity, shock wave in water, and expansion rate of the pipe enclosing the detonation products (in combination with the equilibrium thermodynamic chemistry code BKW) give the C-J state and degree of chemical reaction at the detonation front, as well as information on additional chemical reaction that occurs as the detonation products expand. Specific explosive systems that are studied are ammonium nitrate-fuel oil mixture (ANFO), aluminized ANFO, flaked trinitrotoluene (TNT), and several other commercial products in 10-cm diam and 20-cm-diam pipes of Plexiglas and clay. Experimental shock-pressure data are obtained with lithium niobate transducers placed in the water surrounding the explosive charge. These data show that the addition of approx.100-..mu..m aluminum particles to ANFO significantly increases the initial peak shock pressure delivered to the surrounding medium. Peak shock pressures in the water, calculated from the shock-wave orientation, are also useful in comparing performance properties of various commercial explosives. 20 references, 17 figures, 2 tables.

  20. Nuclear Explosions 1945-1998

    Energy Technology Data Exchange (ETDEWEB)

    Bergkvist, Nils-Olov; Ferm, Ragnhild

    2000-07-01

    The main part of this report is a list of nuclear explosions conducted by the United States, the Soviet Union, the United Kingdom, France, China, India and Pakistan in 1945-98. The list includes all known nuclear test explosions and is compiled from a variety of sources including officially published information from the USA, Russia and France. The details given for each explosion (date, origin time, location, yield, type, etc.) are often compiled from more than one source because the individual sources do not give complete information. The report includes a short background to nuclear testing and provides brief information on the Comprehensive Nuclear-Test-Ban Treaty and the verification regime now being established to verify compliance with the treaty. It also summarizes nuclear testing country by country. The list should be used with some caution because its compilation from a variety of sources means that some of the data could be incorrect. This report is the result of cooperation between the Defence Research Establishment (FOA) and the Stockholm International Peace Research Institute (SIPRI)

  1. A model of vulcanian explosions

    International Nuclear Information System (INIS)

    Woods, A.W.

    1995-01-01

    We present a model of the initial stages of the explosive eruption of magma from a volcanic conduit as occurs in Vulcanian style eruptions. We assume there is a volatile rich (1-10 wt%) mixture of magma, vaporised groundwater and exsolved volatiles, trapped at high pressure (1-100 atm) just below a plug in a volcanic conduit. If the plug disrupts, there is an explosive eruption in which a rarefaction wave propagates into the conduit allowing the volatile rich mixture to expand and discharge into the atmosphere ahead of the vent. Typically, the explosions are so rapid that coarse grained ejecta (>0.5 mm) do not remain in thermal equilibrium with the gas, and this leads to significantly lower velocities and temperatures than predicted by an equilibrium model. Material may erupt from the vent at speeds of 100-400 m s -1 with an initial mass flux of order 10 7 -10 9 kg s -1 , consistent with video observations of eruptions and measurements of the ballistic dispersal of large clasts. (orig.)

  2. The Physical Basis of Lg Generation by Explosion Sources

    Energy Technology Data Exchange (ETDEWEB)

    J. L. Stevens; G. E. Baker; H. Xu; T. J. Bennett; N. Rimer; S. D. Day

    2004-12-20

    The goal of this project has been to develop a quantitative predictive capability for explosion-generated Lg phases with a sound and unambiguous physical basis. The research program consisted of a theoretical investigation of explosion-generated Lg combined with an observational study. The specific question addressed by this research program is how the Lg phase is generated by underground nuclear explosions. This question is fundamental to how Lg phases are interpreted for use in explosion yield estimation and earthquake/explosion discrimination. To constrain modeling, we have extensively reviewed the existing literature and complemented that work with an examination of several explosion data sets, most notably: (1) Degelen Mountain explosions recorded between 7 and 57 km, with corresponding recordings at Borovoye, at approximately 650 km; (2) recordings from Russian deep seismic sounding experiments; (3) NTS explosion sources including the NPE and nuclear tests covering a range of source depths and media properties. A simple point explosion in an infinite medium generates no shear waves, so the Lg phase is generated entirely by non-spherical components of the source and conversions through reflections and scattering. We find that the most important contributors to the Lg phase are: (1) P to S conversion at the free surface and other near source interfaces, (2) S waves generated directly by a realistically distributed explosion source including nonlinear effects due to the free surface and gravity, and (3) Rg scattering to Lg. Additional effects that contribute significantly to Lg are scattering of converted S phases that traps more of the converted P-to-S in the crust, and randomization of the components of Lg. The pS phase from a spherically symmetric explosion source in media with P-wave velocity less than upper mantle S-wave velocity is trapped in the crust and can explain the observed radial and vertical Lg. The free surface pS converted phase from the same

  3. Development of Diesel Engine Operated Forklift Truck for Explosive Gas Atmospheres

    Science.gov (United States)

    Vishwakarma, Rajendra Kumar; Singh, Arvind Kumar; Ahirwal, Bhagirath; Sinha, Amalendu

    2018-02-01

    For the present study, a prototype diesel engine operated Forklift truck of 2 t capacity is developed for explosive gas atmosphere. The parts of the Forklift truck are assessed against risk of ignition of the explosive gases, vapors or mist grouped in Gr. IIA and having ignition temperature more than 200°C. Identification of possible sources of ignition and their control or prevention is the main objective of this work. The design transformation of a standard Forklift truck into a special Forklift truck is made on prototype basis. The safety parameters of the improved Forklift truck are discussed in this paper. The specially designed Forklift truck is useful in industries where explosive atmospheres may present during normal working conditions and risk of explosion is a concern during handling or transportation of materials. This indigenous diesel engine based Forklift truck for explosive gas atmosphere classified as Zone 1 and Zone 2 area and gas group IIA is developed first time in India in association with the Industry.

  4. Correlations between the disintegration of melt and the measured impulses in steam explosions

    Energy Technology Data Exchange (ETDEWEB)

    Froehlich, G.; Linca, A.; Schindler, M. [Univ. of Stuttgart (Germany)

    1995-09-01

    To find our correlations in steam explosions (melt water interactions) between the measured impulses and the disintegration of the melt, experiments were performed in three configurations i.e. stratified, entrapment and jet experiments. Linear correlations were detected between the impulse and the total surface of the fragments. Theoretical considerations point out that a linear correlation assumes superheating of a water layer around the fragments of a constant thickness during the fragmentation process to a constant temperature (here the homogeneous nucleation temperature of water was assumed) and a constant expansion velocity of the steam in the main expansion time. The correlation constant does not depend on melt temperature and trigger pressure, but it depends on the configuration of the experiment or of a scenario of an accident. Further research is required concerning the correlation constant. For analysing steam explosion accidents the explosivity is introduced. The explosivity is a mass specific impulse. The explosivity is linear correlated with the degree of fragmentation. Knowing the degree of fragmentation with proper correlation constant the explosivity can be calculated and from the explosivity combined with the total mass of fragments the impulse is obtained which can be used to an estimation of the maximum force.

  5. Sub-sonic thermal explosions investigated by radiography

    Energy Technology Data Exchange (ETDEWEB)

    Smilowitz, Laura B [Los Alamos National Laboratory; Henson, Bryan F [Los Alamos National Laboratory; Romero, Jerry J [Los Alamos National Laboratory; Asay, Blaine W [Los Alamos National Laboratory

    2010-01-01

    This paper reviews the past 5 years of experiments utilizing radiographic techniques to study defiagration in thermal explosions in HMX based formulations. Details of triggering and timing synchronization are given. Radiographic images collected using both protons and x-rays are presented. Comparisons of experiments with varying size, case confinement, binder, and synchronization are presented. Techniques for quantifying the data in the images are presented and a mechanism for post-ignition burn propagation in a thermal explosion is discussed. From these experiments, we have observed a mechanism for sub-sonic defiagration with both gas phase convective and solid phase conductive burning. The convective front velocity is directly measured from the radiographic images and consumes only a small fraction of the HE. It lights the HE as it passes beginning the slower solid state conductive burn process. This mechanism is used to create a model to simulate the radiographic results and a comparison will be shown.

  6. Out of the frying pan: Explosive droplet dynamics

    Science.gov (United States)

    Marston, Jeremy; Li, Chao; Truscott, Tadd; Mansoor, Mohammad

    2017-11-01

    Regardless of culinary skills, most people who have used a stove top have encountered the result of water interacting with hot oil. The phenomenon is particularly memorable if the result is impingement of hot fluid on one's skin. Whilst ubiquitous, a deeper probing of this phenomenon reveals a vastly rich dynamical process. We use high-speed imaging to investigate the idealized case of a single water droplet impacting onto a hot oil film. At a qualitative level, we have observed three regimes of fluid ejection - jets, cones and explosive vaporization. The latter of these results in the spectacular creation of aerosol with sizes down to the sub-micrometer range. We present our experimental findings based upon control parameters such as temperature, film thickness and oil type.

  7. Gas transport into a cavitation bubble during the explosion

    International Nuclear Information System (INIS)

    Oldenziel, D.M.

    1976-01-01

    When considering cavitation bubbles exploding from small stream nuclei the surface tension plays an important role, and mostly negative pressures exist in the surroundings of such a bubble. During the short explosion time, the gas and vapor pressure in the bubble plays no important role in the dynamic process. The high radial velocity of the bubble wall introduces a steep gradient in the concentration of dissolved air near it, which results in some enforced gas transport into the bubble. During the bubble implosion it is necessary to take into account the amount of gas in the bubble, as it certainly plays an important role in exploring the cavitation erosion. In this survey the solution of a mathematical model for the gas diffusion process is compared with some experimental results

  8. Analysis of slifer data from underground explosions

    International Nuclear Information System (INIS)

    Heusinkveld, M.

    1979-01-01

    A formula describing the distance--time relationship of a shock wave moving outward from an underground explosion is derived. Calculated results are compared with those computed using the LASL and BOTE formulas and with slifer data obtained from field experiments. For many of the field events, the derived curve provides a better fit than do the LASL or BOTE formulas. Methods are presented for the determination of the detonation energy W under three conditions: (a) where time and distance are known accurately; (b) where there is an unknown offset of time and distance; and (c) where there is an unknown offset of both time and distance. These methods are applied with moderate success to a set of (t,r) data supplied by Goldwire

  9. High energy materials. Propellants, explosives and pyrotechnics

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Jai Prakash

    2010-07-01

    Authored by an insider with over 40 years of high energy materials (HEMs) experience in academia, industry and defence organizations, this handbook and ready reference covers all important HEMs from the 1950s to the present with their respective properties and intended purposes. Written at an attainable level for professionals, engineers and technicians alike, the book provides a comprehensive view of the current status and suggests further directions for research and development. An introductory chapter on the chemical and thermodynamic basics allows the reader to become acquainted with the fundamental features of explosives, before moving on to the important safety aspects in processing, handling, transportation and storage of high energy materials. With its collation of results and formulation strategies hitherto scattered in the literature, this should be on the shelf of every HEM researcher and developer. (orig.)

  10. Passive vapor extraction feasibility study

    International Nuclear Information System (INIS)

    Rohay, V.J.

    1994-01-01

    Demonstration of a passive vapor extraction remediation system is planned for sites in the 200 West Area used in the past for the disposal of waste liquids containing carbon tetrachloride. The passive vapor extraction units will consist of a 4-in.-diameter pipe, a check valve, a canister filled with granular activated carbon, and a wind turbine. The check valve will prevent inflow of air that otherwise would dilute the soil gas and make its subsequent extraction less efficient. The granular activated carbon is used to adsorb the carbon tetrachloride from the air. The wind turbine enhances extraction rates on windy days. Passive vapor extraction units will be designed and operated to meet all applicable or relevant and appropriate requirements. Based on a cost analysis, passive vapor extraction was found to be a cost-effective method for remediation of soils containing lower concentrations of volatile contaminants. Passive vapor extraction used on wells that average 10-stdft 3 /min air flow rates was found to be more cost effective than active vapor extraction for concentrations below 500 parts per million by volume (ppm) of carbon tetrachloride. For wells that average 5-stdft 3 /min air flow rates, passive vapor extraction is more cost effective below 100 ppm

  11. The lithium vapor box divertor

    International Nuclear Information System (INIS)

    Goldston, R J; Schwartz, J; Myers, R

    2016-01-01

    It has long been recognized that volumetric dissipation of the plasma heat flux from a fusion power system is preferable to its localized impingement on a material surface. Volumetric dissipation mitigates both the anticipated very high heat flux and intense particle-induced damage due to sputtering. Recent projections to a tokamak demonstration power plant suggest an immense upstream parallel heat flux, of order 20 GW m −2 , implying that fully detached operation may be a requirement for the success of fusion power. Building on pioneering work on the use of lithium by Nagayama et al and by Ono et al as well as earlier work on the gas box divertor by Watkins and Rebut, we present here a concept for a lithium vapor box divertor, in which lithium vapor extracts momentum and energy from a fusion-power-plant divertor plasma, using fully volumetric processes. At the high powers and pressures that are projected this requires a high density of lithium vapor, which must be isolated from the main plasma in order to avoid lithium build-up on the chamber walls or in the plasma. Isolation is achieved through a powerful multi-box differential pumping scheme available only for condensable vapors. The preliminary box-wise calculations are encouraging, but much more work is required to demonstrate the practical viability of this scheme, taking into account at least 2D plasma and vapor flows within and between the vapor boxes and out of the vapor boxes to the main plasma. (paper)

  12. The nature and role of trap states in a dendrimer-based organic field-effect transistor explosive sensor

    Science.gov (United States)

    Tang, Guoqiang; Chen, Simon S. Y.; Lee, Kwan H.; Pivrikas, Almantas; Aljada, Muhsen; Burn, Paul L.; Meredith, Paul; Shaw, Paul E.

    2013-06-01

    We report the fabrication and charge transport characterization of carbazole dendrimer-based organic field-effect transistors (OFETs) for the sensing of explosive vapors. After exposure to para-nitrotoluene (pNT) vapor, the OFET channel carrier mobility decreases due to trapping induced by the absorbed pNT. The influence of trap states on transport in devices before and after exposure to pNT vapor has been determined using temperature-dependent measurements of the field-effect mobility. These data clearly show that the absorption of pNT vapor into the dendrimer active layer results in the formation of additional trap states. Such states inhibit charge transport by decreasing the density of conducting states.

  13. Modeling and measurement of boiling point elevation during water vaporization from aqueous urea for SCR applications

    International Nuclear Information System (INIS)

    Dan, Ho Jin; Lee, Joon Sik

    2016-01-01

    Understanding of water vaporization is the first step to anticipate the conversion process of urea into ammonia in the exhaust stream. As aqueous urea is a mixture and the urea in the mixture acts as a non-volatile solute, its colligative properties should be considered during water vaporization. The elevation of boiling point for urea water solution is measured with respect to urea mole fraction. With the boiling-point elevation relation, a model for water vaporization is proposed underlining the correction of the heat of vaporization of water in the urea water mixture due to the enthalpy of urea dissolution in water. The model is verified by the experiments of water vaporization as well. Finally, the water vaporization model is applied to the water vaporization of aqueous urea droplets. It is shown that urea decomposition can begin before water evaporation finishes due to the boiling-point elevation

  14. Modeling and measurement of boiling point elevation during water vaporization from aqueous urea for SCR applications

    Energy Technology Data Exchange (ETDEWEB)

    Dan, Ho Jin; Lee, Joon Sik [Seoul National University, Seoul (Korea, Republic of)

    2016-03-15

    Understanding of water vaporization is the first step to anticipate the conversion process of urea into ammonia in the exhaust stream. As aqueous urea is a mixture and the urea in the mixture acts as a non-volatile solute, its colligative properties should be considered during water vaporization. The elevation of boiling point for urea water solution is measured with respect to urea mole fraction. With the boiling-point elevation relation, a model for water vaporization is proposed underlining the correction of the heat of vaporization of water in the urea water mixture due to the enthalpy of urea dissolution in water. The model is verified by the experiments of water vaporization as well. Finally, the water vaporization model is applied to the water vaporization of aqueous urea droplets. It is shown that urea decomposition can begin before water evaporation finishes due to the boiling-point elevation.

  15. Dimers in nucleating vapors

    Science.gov (United States)

    Lushnikov, A. A.; Kulmala, M.

    1998-09-01

    The dimer stage of nucleation may affect considerably the rate of the nucleation process at high supersaturation of the nucleating vapor. Assuming that the dimer formation limits the nucleation rate, the kinetics of the particle formation-growth process is studied starting with the definition of dimers as bound states of two associating molecules. The partition function of dimer states is calculated by summing the Boltzmann factor over all classical bound states, and the equilibrium population of dimers is found for two types of intermolecular forces: the Lennard-Jones (LJ) and rectangular well+hard core (RW) potentials. The principle of detailed balance is used for calculating the evaporation rate of dimers. The kinetics of the particle formation-growth process is then investigated under the assumption that the trimers are stable with respect to evaporation and that the condensation rate is a power function of the particle mass. If the power exponent λ=n/(n+1) (n is a non-negative integer), the kinetics of the process is described by a finite set of moments of particle mass distribution. When the characteristic time of the particle formation by nucleation is much shorter than that of the condensational growth, n+2 universal functions of a nondimensional time define the kinetic process. These functions are calculated for λ=2/3 (gas-to-particle conversion in the free molecular regime) and λ=1/2 (formation of islands on surfaces).

  16. Water vapor variability and comparisons in the subtropical Pacific from The Observing System Research and Predictability Experiment-Pacific Asian Regional Campaign (T-PARC) Driftsonde, Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC), and reanalyses

    Science.gov (United States)

    Wang, Junhong; Zhang, Liangying; Lin, Po-Hsiung; Bradford, Mark; Cole, Harold; Fox, Jack; Hock, Terry; Lauritsen, Dean; Loehrer, Scot; Martin, Charlie; Vanandel, Joseph; Weng, Chun-Hsiung; Young, Kathryn

    2010-11-01

    During the THORPEX (The Observing System Research and Predictability Experiment) Pacific Asian Regional Campaign (T-PARC), from 1 August to 30 September 2008, ˜1900 high-quality, high vertical resolution soundings were collected over the Pacific Ocean. These include dropsondes deployed from four aircrafts and zero-pressure balloons in the stratosphere (NCAR's Driftsonde system). The water vapor probability distribution and spatial variability in the northern subtropical Pacific (14°-20°N, 140°E-155°W) are studied using Driftsonde and COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) data and four global reanalysis products. Driftsonde data analysis shows distinct differences of relative humidity (RH) distributions in the free troposphere between the Eastern and Western Pacific (EP and WP, defined as east and west of 180°, respectively), very dry with a single peak of ˜1% RH in the EP and bi-modal distributions in the WP with one peak near ice saturation and one varying with altitude. The frequent occurrences of extreme dry air are found in the driftsonde data with 59% and 19% of RHs less than or equal to 5% and at 1% at 500 hPa in the EP, respectively. RH with respect to ice in the free troposphere exhibits considerable longitudinal variations, very low (problems in Driftsonde, two National Center for Environmental Prediction (NCEP) reanalyses and COSMIC data. The moist layer at 200-100 hPa in the WP shown in the ERA-Interim, JRA and COSMIC is missing in Driftsonde data. Major problems are found in the RH means and variability over the study region for both NCEP reanalyses. Although the higher-moisture layer at 200-100 hPa in the WP in the COSMIC data agrees well with the ERA-Interim and JRA, it is primarily attributed to the first guess of the 1-Dimensional (1D) variational analysis used in the COSMIC retrieval rather than the refractivity measurements. The limited soundings (total 268) of Driftsonde data are capable of

  17. Electromagnetic Effects in SDF Explosions

    Energy Technology Data Exchange (ETDEWEB)

    Reichenbach, H; Neuwald, P; Kuhl, A L

    2010-02-12

    The notion of high ion and electron concentrations in the detonation of aluminized explosive mixtures has aroused some interest in electro-magnetic effects that the SDF charges might generate when detonated. Motivated by this interest we have started to investigate whether significant electro-magnetic effects show up in our small-scale experiments. However, the design of instrumentation for this purpose is far from straightforward, since there are a number of open questions. Thus the main aim of the feasibility tests is to find - if possible - a simple and reliable method that can be used as a diagnostic tool for electro-magnetic effects. SDF charges with a 0.5-g PETN booster and a filling of 1 g aluminum flakes have been investigated in three barometric bomb calorimeters with volumes ranging from 6.3 l to of 6.6 l. Though similar in volume, the barometric bombs differed in the length-to-diameter ratio. The tests were carried out with the bombs filled with either air or nitrogen at ambient pressure. The comparison of the test in air to those in nitrogen shows that the combustion of TNT detonation products or aluminum generates a substantial increase of the quasi-steady overpressure in the bombs. Repeated tests in the same configuration resulted in some scatter of the experimental results. The most likely reason is that the aluminum combustion in most or all cases is incomplete and that the amount of aluminum actually burned varies from test to test. The mass fraction burned apparently decreases with increasing aspect ratio L/D. Thus an L/D-ratio of about 1 is optimal for the performance of shock-dispersed-fuel combustion. However, at an L/D-ratio of about 5 the combustion still yields appreciable overpressure in excess of the detonation. For a multi-burst scenario in a tunnel environment with a number of SDF charges distributed along a tunnel section a spacing of 5 tunnel diameter and a fuel-specific volume of around 7 l/g might provide an acceptable compromise

  18. The non-proliferation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Hannon, W.J. [Lawrence Livermore National Lab., CA (United States)

    1994-12-31

    On September 22, 1993, the Department of Energy detonated more than 1.2 million kg of blasting agent in a tunnel in Rainier Mesa at the Nevada Test Site. The resulting explosion generated seismic, electromagnetic, and air pressure signals that were recorded on instruments deployed at distances ranging from a few meters to hundreds and, in some cases, thousands of kilometers. More than 12 organizations made measurements before, during, and after the explosions. The explosion and its associated experiments are known as the Non-Proliferation Experiment (NPE). Analyses of the measurements made during the NPE and comparisons with similar measurements made on previous nearly nuclear explosions and on a co-located smaller explosion detonated at the same site are providing basic phenomenological insights into what is potentially one of the comprehensive Test Ban Treaty (CTBT)-distinguishing between nuclear explosions and some of the many conventional explosions that occur each year. The NPE is also providing information on the use of chemical explosions to develop empirical discriminants in regions where no nuclear explosions have been recorded. In another verification application, several NPE projects are examining the utility of on-site, pre-shot, shot-time, and post-shot measurements of gas seepage, seismic activity, and other observables as a means of identifying the source of signals that appear like nuclear explosions at regional distances. Two related activities are being considered. First, challenge on-site inspections, conducted after an event has occurred, may be able to use the characteristics of phenomena that persist after the explosion to detect and identify the source of the signals that appeared ambiguous or explosion-like to remote sensors. Second, cooperative, on-site measurements made at the time of a pre-nounced conventional explosion may provide assurance that a nuclear explosion did not occur as part of or in place of the pre-announced explosion.

  19. Steam explosion pretreatment of softwood: the effect of the explosive decompression on enzymatic digestibility.

    Science.gov (United States)

    Pielhop, Thomas; Amgarten, Janick; von Rohr, Philipp Rudolf; Studer, Michael H

    2016-01-01

    Steam explosion pretreatment has been examined in many studies for enhancing the enzymatic digestibility of lignocellulosic biomass and is currently the most common pretreatment method in commercial biorefineries. The information available about the effect of the explosive decompression on the biochemical conversion is, however, very limited, and no studies prove that the latter is actually enhanced by the explosion. Hence, it is of great value to discern between the effect of the explosion on the one hand and the steaming on the other hand, to identify their particular influences on enzymatic digestibility. The effect of the explosive decompression in the steam explosion pretreatment of spruce wood chips on their enzymatic cellulose digestibility was studied systematically. The explosion had a high influence on digestibility, improving it by up to 90 % compared to a steam pretreatment without explosion. Two factors were identified to be essentially responsible for the effect of the explosion on enzymatic digestibility: pretreatment severity and pressure difference of the explosion. A higher pretreatment severity can soften up and weaken the lignocellulose structure more, so that the explosion can better break up the biomass and decrease its particle size, which enhances its digestibility. In particular, increasing the pressure difference of the explosion leads to more defibration, a smaller particle size and a better digestibility. Though differences were found in the micro- and nanostructure of exploded and non-exploded biomass, the only influence of the explosion on digestibility was found to be the macroscopic particle size reduction. Steam explosion treatments with a high severity and a high pressure difference of the explosion lead to a comparatively high cellulose digestibility of the-typically very recalcitrant-softwood biomass. This is the first study to show that explosion can enhance the enzymatic digestibility of lignocellulosic biomass. If the

  20. Quantum control for initiation and detection of explosives

    International Nuclear Information System (INIS)

    Greenfield, Margo T.; McGrane, Shawn D.; Scharff, R. Jason; Moore, David S.

    2010-01-01

    We employ quantum control methods towards detection and quantum controlled initiation (QCI) of energetic materials. Ultrafast pulse shaping of broadband Infrared (∼750 nm to 850 run) and ultraviolet (266 nm, 400 nm) light is utilized for control. The underlying principals behind optimal control can be utilized to both detect and initiate explosives. In each case, time dependent phase shaped electric fields drive the chemical systems towards a desired state. For optimal dynamic detection of explosives (ODD-Ex) a phase specific broadband infrared pulse is created which increases not only the sensitivity of detection but also the selectivity of an explosive's spectral signatures in a background of interferents. QCI on the other hand, seeks to initiate explosives by employing shaped ultraviolet light. QCI is ideal for use with explosive detonators as it removes the possibility of unintentional initiation from an electrical source while adding an additional safety feature, initiation only with the proper pulse shape. Quantum control experiments require: (1) the ability to phase and amplitude shape the laser pulse and (2) the ability to effectively search for the pulse shape which controls the reaction. In these adaptive experiments we utilize both global and local optimization search routines such as genetic algorithm, differential evolution, and downhill simplex. Pulse shaping the broadband IR light, produced by focusing 800 nm light through a pressurized tube of Argon, is straightforward as commercial pulse shapers are available at and around 800 nm. Pulse shaping in the UV requires a home built shaper. Our system is an acoustic optical modulator (AOM) pulse shaper in which consists of a fused silica AOM crystal placed in the Fourier plane of a 4-f zero dispersion compressor.