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Sample records for thermal explosion experiment

  1. 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.

  2. 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)

  3. 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.)

  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. 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.

  6. 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

  7. 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

  8. 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

  9. 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)

  10. Experimental-theoretical investigation of the thermal explosion

    International Nuclear Information System (INIS)

    Zyszkowski, W.

    It is suggested that thermal explosions are caused by the latent heat of fusion liberated when the heat transfer at the surface of the molten metal mass is sufficiently intensive to subcool the metal below the solidification point. From a couple of experiments performed by the authors on different metals brought into contact in the molten state with cold water as well as from experiments of the same kind in other laboratories it can be concluded that thermal explosions appear only under special, precisely determined conditions. The experimental techniques applied in this work comprise measurement of the temperature history during the thermal interaction of the hot and the cold liquid and simultaneously observe and record the phenomena by fast photography

  11. 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.

  12. One-Dimensional Time to Explosion (Thermal Sensitivity) of ANPZ

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hust, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McClelland, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gresshoff, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-11-12

    Incidents caused by fire and combat operations can heat energetic materials that may lead to thermal explosion and result in structural damage and casualty. Some explosives may thermally explode at fairly low temperatures (< 100 C) and the violence from thermal explosion may cause a significant damage. Thus it is important to understand the response of energetic materials to thermal insults. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory has been used for decades to measure times to explosion, threshold thermal explosion temperature, and determine kinetic parameters of energetic materials. Samples of different configurations (pressed part, powder, paste, and liquid) can be tested in the system. The ODTX testing can also provide useful data for assessing the thermal explosion violence of energetic materials. This report summarizes the recent ODTX experimental data and modeling results for 2,6-diamino-3,5-dintropyrazine (ANPZ).

  13. 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

  14. Study of thermal sensitivity and thermal explosion violence of energetic materials in the LLNL ODTX system

    International Nuclear Information System (INIS)

    Hsu, P C; Hust, G; Zhang, M X; Lorenz, T K; Reynolds, J G; Fried, L; Springer, H K; Maienschein, J L

    2014-01-01

    Incidents caused by fire and combat operations can heat energetic materials that may lead to thermal explosion and result in structural damage and casualty. Some explosives may thermally explode at fairly low temperatures (< 100 °C) and the violence from thermal explosion may cause significant damage. Thus it is important to understand the response of energetic materials to thermal insults. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory has been used for decades to measure times to explosion, threshold thermal explosion temperature, and determine kinetic parameters of energetic materials. Samples of different configurations (pressed part, powder, paste, and liquid) can be tested in the system. The ODTX testing can also provide useful data for assessing the thermal explosion violence of energetic materials. Recent ODTX experimental data are reported in the paper.

  15. Burn propagation in a PBX 9501 thermal explosion

    International Nuclear Information System (INIS)

    Henson, B. F.; Smilowitz, L.; Romero, J. J.; Sandstrom, M. M.; Asay, B. W.; Schwartz, C.; Saunders, A.; Merrill, F.; Morris, C.; Murray, M. M.; McNeil, W. V.; Marr-Lyon, M.; Rightley, P. M.

    2007-01-01

    We have applied proton radiography to study the conversion of solid density to gaseous combustion products subsequent to ignition of a thermal explosion in PBX 9501. We apply a thermal boundary condition to the cylindrical walls of the case, ending with an induction period at 205 C. We then introduce a laser pulse that accelerates the thermal ignition and synchronizes the explosion with the proton accelerator. We then obtain fast, synchronized images of the evolution of density loss with few microsecond resolution during the approximately 100 microsecond duration of the explosion. We present images of the solid explosive during the explosion and discuss measured rates and assumed mechanisms of burning the role of pressure in this internal burning

  16. 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)

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

    Science.gov (United States)

    Turcotte, R; Lightfoot, P D; Fouchard, R; Jones, D E G

    2003-07-04

    Ammonium nitrate (AN) is an essential ingredient in most fertilizers. It is also widely used in the commercial explosives industry. In this latter application, it is mostly mixed with fuel oil to form the most popular commercial explosive: ANFO. In both the fertilizer and the explosive industry, aqueous AN solutions (ANS) of various concentrations are processed. These solutions also form the basis of ammonium nitrate emulsion explosives (also called ammonium nitrate emulsions or ANE), which are produced either in bulk or in packaged form. For all these AN-based products, quantities of the order of 20,000kg are being manufactured, transported, stored, and processed at elevated temperatures and/or elevated pressures. Correspondingly, major accidents involving overheating of large quantities of these products have happened in several of these operations. In comparison, convenient laboratory quantities to investigate thermal decomposition properties are generally less than 1kg. As a result, in order to provide information applicable to real-life situations, any laboratory study must use techniques that minimize heat losses from the samples to their environment. In the present study, two laboratory-scale calorimeters providing an adiabatic environment were used: an accelerating rate calorimeter (ARC) and an adiabatic Dewar calorimeter (ADC). Experiments were performed on pure AN, ANFO, various ANS systems, and typical bulk and packaged ANE systems. The effects of sample mass, atmosphere, and formulation on the resulting onset temperatures were studied. A comparison of the results from the two techniques is provided and a proposed method to extrapolate these results to large-scale inventories is examined.

  18. Differential thermal analysis microsystem for explosive detection

    DEFF Research Database (Denmark)

    Olsen, Jesper Kenneth; Greve, Anders; Senesac, L.

    2011-01-01

    as a small silicon nitride membrane incorporating heater elements and a temperature measurement resistor. In this manuscript the DTA system is described and tested by measuring calorimetric response of 3 different kinds of explosives (TNT, RDX and PETN). This project is carried out under the framework...

  19. 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.

  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. ONE-DIMENSIONAL TIME TO EXPLOSION (THERMAL SENSITIVITY) TESTS ON PETN, PBX-9407, LX-10, AND LX-17

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Strout, Steve [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McClelland, Matthew [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ellsworth, Fred Ellsworth [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-28

    Incidents caused by fire and combat operations can heat energetic materials that may lead to thermal explosion and result in structural damage and casualty. Some explosives may thermally explode at fairly low temperatures (< 100 C) and the violence from thermal explosion may cause a significant damage. Thus it is important to understand the response of energetic materials to thermal insults. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory has been used for decades to measure times to thermal explosion, threshold thermal explosion temperature, and determine the kinetic parameters of thermal decomposition of energetic materials. Samples of different configurations (pressed part, powder, paste, and liquid) can be tested in the system. The ODTX testing can also provide useful data for assessing the thermal explosion violence of energetic materials. This report summarizes the results of our recent ODTX experiments on PETN powder, PBX-9407 pressed part, LX-10 pressed part, LX-17 pressed part and compares the test data that were obtained decades ago with the older version of ODTX system. Test results show the thermal sensitivity of various materials tested in the following order: PETN> PBX-9407 > LX-10 > LX-17.

  2. Modeling solid thermal explosion containment on reactor HNIW and HMX

    International Nuclear Information System (INIS)

    Lin, Chun-Ping; Chang, Chang-Ping; Chou, Yu-Chuan; Chu, Yung-Chuan; Shu, Chi-Min

    2010-01-01

    2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaaza-isowurtzitane (HNIW), also known as CL-20 and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), are highly energetic materials which have been popular in national defense industries for years. This study established the models of thermal decomposition and thermal explosion hazard for HNIW and HMX. Differential scanning calorimetry (DSC) data were used for parameters determination of the thermokinetic models, and then these models were employed for simulation of thermal explosion in a 437 L barrel reactor and a 24 kg cubic box package. Experimental results indicating the best storage conditions to avoid any violent runaway reaction of HNIW and HMX were also discovered. This study also developed an efficient procedure regarding creation of thermokinetics and assessment of thermal hazards of HNIW and HMX that could be applied to ensure safe storage conditions.

  3. 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.

  4. 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.

  5. 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...

  6. Standoff laser-induced thermal emission of explosives

    Science.gov (United States)

    Galán-Freyle, Nataly Y.; Pacheco-Londoño, Leonardo C.; Figueroa-Navedo, Amanda; Hernandez-Rivera, Samuel P.

    2013-05-01

    A laser mediated methodology for remote thermal excitation of analytes followed by standoff IR detection is proposed. The goal of this study was to determine the feasibility of using laser induced thermal emission (LITE) from vibrationally excited explosives residues deposited on surfaces to detect explosives remotely. Telescope based FT-IR spectral measurements were carried out to examine substrates containing trace amounts of threat compounds used in explosive devices. The highly energetic materials (HEM) used were PETN, TATP, RDX, TNT, DNT and ammonium nitrate with concentrations from 5 to 200 μg/cm2. Target substrates of various thicknesses were remotely heated using a high power CO2 laser, and their mid-infrared (MIR) thermally stimulated emission spectra were recorded. The telescope was configured from reflective optical elements in order to minimize emission losses in the MIR frequencies and to provide optimum overall performance. Spectral replicas were acquired at a distance of 4 m with an FT-IR interferometer at 4 cm- 1 resolution and 10 scans. Laser power was varied from 4-36 W at radiation exposure times of 10, 20, 30 and 60 s. CO2 laser powers were adjusted to improve the detection and identification of the HEM samples. The advantages of increasing the thermal emission were easily observed in the results. Signal intensities were proportional to the thickness of the coated surface (a function of the surface concentration), as well as the laser power and laser exposure time. For samples of RDX and PETN, varying the power and time of induction of the laser, the calculated low limit of detections were 2 and 1 μg/cm2, respectively.

  7. 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.

  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. Thermal Radiation Effects on Thermal Explosion in Polydisperse Fuel Spray-Probabilistic Model

    Directory of Open Access Journals (Sweden)

    Ophir Navea

    2011-06-01

    Full Text Available We investigate the effect of thermal radiation on the dynamics of a thermal explosion of polydisperse fuel spray with a complete description of the chemistry via a single-step two-reactant model of general order. The polydisperse spray is modeled using a Probability Density Function (PDF. The thermal radiation energy exchange between the evaporation surface of the fuel droplets and the burning gas is described using the Marshak boundary conditions. An explicit expression of the critical condition for thermal explosion limit is derived analytically and represents a generalization of the critical parameter of the classical Semenov theory. Because we investigated the model in the range where the temperature is very high, the effect of the thermal radiation is significant.

  10. 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.

  11. 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

  12. Modeling of composite synthesis in conditions of controlled thermal explosion

    Science.gov (United States)

    Kukta, Yaroslav; Knyazeva, Anna

    2017-12-01

    The paper proposes the model for the titanium-based composite synthesis from powders of titanium and carbon of non-stoichiometric composition. The model takes into account the mixture heating from chamber walls, the dependence of liquidus and solidus temperatures on the composition of reacting mixture and the formation of possible irreversible phases. The reaction retardation by the reaction product is taken into consideration in kinetic laws. As an example, the results of temperature and conversion level calculation are presented for the system Ti-C with the summary reaction for different temperatures of chamber walls heating. It was revealed that the reaction retardation being the reaction product can be the cause of incomplete conversion in the thermal explosion conditions. Non-stoichiometric composition leads to the conditions of degenerated mode when some additional heating is necessary to complete the reaction.

  13. Modeling of thermal explosion under pressure in metal ceramic systems

    International Nuclear Information System (INIS)

    Shapiro, M.; Dudko, V.; Skachek, B.; Matvienko, A.; Gotman, I.; Gutmanas, E.Y.

    1998-01-01

    The process of reactive in situ synthesis of dense ceramic matrix composites in Ti-B-C, Ti-B-N, Ti-Si-N systems is modeled. These ceramics are fabricated on the basis of compacted blends of ceramic powders, namely Ti-B 4 C and/or Ti-BN. The objectives of the project are to identify and investigate the optimal thermal conditions preferable for production of fully dense ceramic matrix composites. Towards this goal heat transfer and combustion in dense and porous ceramic blends are investigated during monotonous heating at a constant rate. This process is modeled using a heat transfer-combustion model with kinetic parameters determined from the differential thermal analysis of the experimental data. The kinetic burning parameters and the model developed are further used to describe the thermal explosion synthesis in a restrained die under pressure. It is shown that heat removal from the reaction zone affects the combustion process and the final phase composition

  14. 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.

  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. 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.

  17. Pressure Wave Measurements from Thermal Cook-Off of an HMX Based High Explosive PBX 9501

    International Nuclear Information System (INIS)

    Garcia, F.; Forbes, J.W.; Tarver, C.M.; Urtiew, P.A.; Greenwood, D.W.; Vandersall, K.S.

    2001-01-01

    A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting pressure wave and how this wave propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios

  18. 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)

  19. Application of heat-balance integral method to conjugate thermal explosion

    Directory of Open Access Journals (Sweden)

    Novozhilov Vasily

    2009-01-01

    Full Text Available Conjugate thermal explosion is an extension of the classical theory, proposed and studied recently by the author. The paper reports application of heat-balance integral method for developing phase portraits for systems undergoing conjugate thermal explosion. The heat-balance integral method is used as an averaging method reducing partical differential equation problem to the set of first-order ordinary differential equations. The latter reduced problem allows natural interpretation in appropriately chosen phase space. It is shown that, with the help of heat-balance integral technique, conjugate thermal explosion problem can be described with a good accuracy by the set of non-linear first-order differential equations involving complex error function. Phase trajectories are presented for typical regimes emerging in conjugate thermal explosion. Use of heat-balance integral as a spatial averaging method allows efficient description of system evolution to be developed.

  20. Recent advances in thermal analysis and stability evaluation of insensitive plastic bonded explosives (PBXs)

    International Nuclear Information System (INIS)

    Yan, Qi-Long; Zeman, Svatopluk; Elbeih, Ahmed

    2012-01-01

    Highlights: ► We summarize currently used insensitive polymer based explosives and their ingredients. ► We examine the calculation methods that are suitable for kinetic evaluation of polymer based explosives. ► The calculation method for thermal stability parameters of polymer based explosives are summarized, which mainly include shelf life, explosion delay, critical temperature, thermostability threshold, 500 day cookoff temperature and approximate time to explosion. ► The polymer bases could greatly affect the thermal properties of PBXs, including their thermal stability, kinetic parameters and thermodynamic properties. ► PBXs, containing some innovative energetic fillers such as CL-20, NTO, Fox-12 and BCHMX, are only at design stage, which need more research work in the future. - Abstract: In this paper, several fundamental investigations published over the past decades with regard to the thermal analysis of polymer-based explosives (PBXs) have been briefly reviewed. A number of explosive fillers and polymer bases that were used as their main ingredients of PBXs are summarized herein. In addition, the calculation methods for their decomposition kinetics and thermal stability parameters are also introduced in detail. It was concluded that only PBXs based on HMX, RDX and TATB have been widely investigated, and that some other PBXs containing innovative fillers, such as CL-20, TNAZ, NTO and BCHMX are at the design stage. The isoconversional methods and model fitting procedures are usually used to analyze the discrete thermolysis processes of PBXs. In addition, their thermal stability parameters such as shelf life, explosion delay, critical temperature, thermostability threshold, 500-day cookoff temperature and approximate time to explosion could be calculated easily from the kinetic data.

  1. Thermal stability and mechanism of decomposition of emulsion explosives in the presence of pyrite

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhi-Xiang; Wang, Qian [School of Energy and Power Engineering, Jiangsu University, Zhenjiang 212013 (China); Fu, Xiao-Qi, E-mail: xzx19820708@163.com [School of Chemistry and Chemical Engineering, Jiangsu University Zhenjiang 212013 (China)

    2015-12-30

    Highlights: • An exothermic reaction occurs at about 200 °C between pyrite and ammonium nitrate (emulsion explosives). • The essence of reaction between emulsion explosives and pyrite is reaction between ammonium nitrate and pyrite. • The excellent thermal stability of emulsion explosives does not mean it was also showed when pyrite was added. • A new overall reaction has been proposed as: • 14FeS{sub 2}(s) + 91NH{sub 4}NO{sub 3}(s) → 52NO(g) + 26SO{sub 2}(g) + 6Fe{sub 2}O{sub 3}(s) + 78NH{sub 3}(g) + 26N{sub 2}O(g) + 2FeSO{sub 4}(s) + 65H{sub 2}O(g). - Abstract: The reaction of emulsion explosives (ammonium nitrate) with pyrite was studied using techniques of TG-DTG-DTA. TG–DSC–MS was also used to analyze samples thermal decomposition process. When a mixture of pyrite and emulsion explosives was heated at a constant heating rate of 10 K/min from room temperature to 350 °C, exothermic reactions occurred at about 200 °C. The essence of reaction between emulsion explosives and pyrite is the reaction between ammonium nitrate and pyrite. Emulsion explosives have excellent thermal stability but it does not mean it showed the same excellent thermal stability when pyrite was added. Package emulsion explosives were more suitable to use in pyrite shale than bulk emulsion explosives. The exothermic reaction was considered to take place between ammonium nitrate and pyrite where NO, NO{sub 2}, NH{sub 3}, SO{sub 2} and N{sub 2}O gases were produced. Based on the analysis of the gaseous, a new overall reaction was proposed, which was thermodynamically favorable. The results have significant implication in the understanding of stability of emulsion explosives in reactive mining grounds containing pyrite minerals.

  2. Thermal stability and mechanism of decomposition of emulsion explosives in the presence of pyrite

    International Nuclear Information System (INIS)

    Xu, Zhi-Xiang; Wang, Qian; Fu, Xiao-Qi

    2015-01-01

    Highlights: • An exothermic reaction occurs at about 200 °C between pyrite and ammonium nitrate (emulsion explosives). • The essence of reaction between emulsion explosives and pyrite is reaction between ammonium nitrate and pyrite. • The excellent thermal stability of emulsion explosives does not mean it was also showed when pyrite was added. • A new overall reaction has been proposed as: • 14FeS_2(s) + 91NH_4NO_3(s) → 52NO(g) + 26SO_2(g) + 6Fe_2O_3(s) + 78NH_3(g) + 26N_2O(g) + 2FeSO_4(s) + 65H_2O(g). - Abstract: The reaction of emulsion explosives (ammonium nitrate) with pyrite was studied using techniques of TG-DTG-DTA. TG–DSC–MS was also used to analyze samples thermal decomposition process. When a mixture of pyrite and emulsion explosives was heated at a constant heating rate of 10 K/min from room temperature to 350 °C, exothermic reactions occurred at about 200 °C. The essence of reaction between emulsion explosives and pyrite is the reaction between ammonium nitrate and pyrite. Emulsion explosives have excellent thermal stability but it does not mean it showed the same excellent thermal stability when pyrite was added. Package emulsion explosives were more suitable to use in pyrite shale than bulk emulsion explosives. The exothermic reaction was considered to take place between ammonium nitrate and pyrite where NO, NO_2, NH_3, SO_2 and N_2O gases were produced. Based on the analysis of the gaseous, a new overall reaction was proposed, which was thermodynamically favorable. The results have significant implication in the understanding of stability of emulsion explosives in reactive mining grounds containing pyrite minerals.

  3. 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

  4. Forensic analysis methodology for thermal and chemical characterization of homemade explosives

    International Nuclear Information System (INIS)

    Nazarian, Ashot; Presser, Cary

    2014-01-01

    Highlights: • Identification of homemade explosives (HME) is critical for determining the origin of explosive precursor materials. • A novel laser-heating technique was used to obtain the thermal/chemical signatures of HME precursor materials. • Liquid-fuel saturation of the pores of a solid porous oxidizer affected the total specific heat release. • Material thermal signatures were dependent on sample mass and heating rate. • This laser-heating technique can be a useful diagnostic tool for characterizing the thermochemical behavior of HMEs. - Abstract: Forensic identification of homemade explosives is critical for determining the origin of the explosive materials and precursors, and formulation procedures. Normally, the forensic examination of the pre- and post-blast physical evidence lacks specificity for homemade-explosive identification. The focus of this investigation was to use a novel measurement technique, referred to as the laser-driven thermal reactor, to obtain the thermal/chemical signatures of homemade-explosive precursor materials. Specifically, nitromethane and ammonium nitrate were studied under a variety of operating conditions and protocols. Results indicated that liquid-fuel saturation of the internal pores of a solid particle oxidizer appear to be a limiting parameter for the total specific heat release during exothermic processes. Results also indicated that the thermal signatures of these materials are dependent on sample mass and heating rate, for which this dependency may not be detectable by other commercially available thermal analysis techniques. This study has demonstrated that the laser-driven thermal reactor can be a useful diagnostic tool for characterizing the thermal and chemical behavior of trace amounts of homemade-explosive materials

  5. Thermal stability and mechanism of decomposition of emulsion explosives in the presence of pyrite.

    Science.gov (United States)

    Xu, Zhi-Xiang; Wang, Qian; Fu, Xiao-Qi

    2015-12-30

    The reaction of emulsion explosives (ammonium nitrate) with pyrite was studied using techniques of TG-DTG-DTA. TG-DSC-MS was also used to analyze samples thermal decomposition process. When a mixture of pyrite and emulsion explosives was heated at a constant heating rate of 10K/min from room temperature to 350°C, exothermic reactions occurred at about 200°C. The essence of reaction between emulsion explosives and pyrite is the reaction between ammonium nitrate and pyrite. Emulsion explosives have excellent thermal stability but it does not mean it showed the same excellent thermal stability when pyrite was added. Package emulsion explosives were more suitable to use in pyrite shale than bulk emulsion explosives. The exothermic reaction was considered to take place between ammonium nitrate and pyrite where NO, NO2, NH3, SO2 and N2O gases were produced. Based on the analysis of the gaseous, a new overall reaction was proposed, which was thermodynamically favorable. The results have significant implication in the understanding of stability of emulsion explosives in reactive mining grounds containing pyrite minerals. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. 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.

  7. 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)

  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. 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

  10. Detection of plastic explosives using thermal neutron radiography

    International Nuclear Information System (INIS)

    Hacidume, Leo Ryoske

    1999-12-01

    The work aims to demonstrate the potentiality of the neutron radiography technique, allied to the computerized tomography by transmission, to both detect and visualize plastic explosive samples in several hidden conditions, using a simple scanner as a digitalisation instrument. Each tomographic essay was obtained in the J-9 channel of the Argonauta Research Reactor of IEN/CNEN, in groups of six neutron radiographic projections, performed with an angular increment of 30 deg C, in a period of time of 30 minutes for each projection. Two groups of tomographic reconstructions were generated, distinguished by the digitalisation process of the interested lines in the reconstruction plane coming from the projection groups, utilization a scanner and a microdensitometer, respectively. The reconstruction of the bi-dimensional image of the transverse section, in relation to this plane, was processed making use of the Image Reconstruction Algorithmic of an Image based on the Maximum Entropy principle (ARIEM). From the qualitative analysis of the images, we conclude that the neutron radiographic system was able to detect the explosive sample in a satisfactory way while the quantitative analysis confirmed the application effectiveness of a scanner to acquire the projection dates whose objective is only a reconnaissance. (author)

  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. Trace level detection of explosives in solution using leidenfrost phenomenon assisted thermal desorption ambient mass spectrometry.

    Science.gov (United States)

    Saha, Subhrakanti; Mandal, Mridul Kanti; Chen, Lee Chuin; Ninomiya, Satoshi; Shida, Yasuo; Hiraoka, Kenzo

    2013-01-01

    The present paper demonstrates the detection of explosives in solution using thermal desorption technique at a temperature higher than Leidenfrost temperature of the solvent in combination with low temperature plasma (LTP) ionization. Leidenfrost temperature of a solvent is the temperature above which the solvent droplet starts levitation instead of splashing when placed on a hot metallic surface. During this desorption process, slow and gentle solvent evaporation takes place, which leads to the pre-concentration of less-volatile explosive molecules in the droplet and the explosive molecules are released at the last moment of droplet evaporation. The limits of detection for explosives studied by using this thermal desorption LTP ionization method varied in a range of 1 to 10 parts per billion (ppb) using a droplet volume of 20 μL (absolute sample amount 90-630 fmol). As LTP ionization method was applied and ion-molecule reactions took place in ambient atmosphere, various ion-molecule adduct species like [M+NO2](-), [M+NO3](-), [M+HCO3](-), [M+HCO4](-) were generated together with [M-H](-) peak. Each peak was unambiguously identified using 'Exactive Orbitrap' mass spectrometer in negative ionization mode within 3 ppm deviation compared to its exact mass. This newly developed technique was successfully applied to detect four explosives contained in the pond water and soil sample with minor sample pre-treatment and the explosives were detected with ppb levels. The present method is simple, rapid and can detect trace levels of explosives with high specificity from solutions.

  13. The evolution of solid density within a thermal explosion II. Dynamic proton radiography of cracking and solid consumption by burning

    International Nuclear Information System (INIS)

    Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.; Saunders, A.; Merrill, F. E.; Morris, C. L.; Kwiatkowski, K.; Grim, G.; Mariam, F.; Schwartz, C. L.; Hogan, G.; Nedrow, P.; Murray, M. M.; Thompson, T. N.; Espinoza, C.; Lewis, D.; Bainbridge, J.; McNeil, W.; Rightley, P.

    2012-01-01

    We report proton transmission images obtained subsequent to the laser assisted thermal ignition of a sample of PBX 9501 (a plastic bonded formulation of the explosive nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)). We describe the laser assisted thermal ignition technique as a means to synchronize a non-linear thermal ignition event while preserving the subsequent post-ignition behavior. We have obtained dynamic proton transmission images at two spatial magnifications and viewed both the radial and transverse axis of a solid cylindrical sample encased in aluminum. Images have been obtained with 3 to 15 μs temporal resolution and approximately 100 μm spatial resolution at the higher magnification. We observe case expansion from very early in the experiment, until case fragmentation. We observe spatially anisotropic features in the transmission which we attribute to cracking in the solid explosive, in agreement with previous measurements conducted on two dimensional samples with optical viewing. Digital analysis of the images also reveals spatially isotropic features which we attribute to the evolution of the loss of density by burning subsequent to thermal ignition.

  14. The evolution of solid density within a thermal explosion II. Dynamic proton radiography of cracking and solid consumption by burning

    Energy Technology Data Exchange (ETDEWEB)

    Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.; Saunders, A.; Merrill, F. E.; Morris, C. L.; Kwiatkowski, K.; Grim, G.; Mariam, F.; Schwartz, C. L.; Hogan, G.; Nedrow, P.; Murray, M. M.; Thompson, T. N.; Espinoza, C.; Lewis, D.; Bainbridge, J.; McNeil, W.; Rightley, P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); and others

    2012-05-15

    We report proton transmission images obtained subsequent to the laser assisted thermal ignition of a sample of PBX 9501 (a plastic bonded formulation of the explosive nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)). We describe the laser assisted thermal ignition technique as a means to synchronize a non-linear thermal ignition event while preserving the subsequent post-ignition behavior. We have obtained dynamic proton transmission images at two spatial magnifications and viewed both the radial and transverse axis of a solid cylindrical sample encased in aluminum. Images have been obtained with 3 to 15 {mu}s temporal resolution and approximately 100 {mu}m spatial resolution at the higher magnification. We observe case expansion from very early in the experiment, until case fragmentation. We observe spatially anisotropic features in the transmission which we attribute to cracking in the solid explosive, in agreement with previous measurements conducted on two dimensional samples with optical viewing. Digital analysis of the images also reveals spatially isotropic features which we attribute to the evolution of the loss of density by burning subsequent to thermal ignition.

  15. GCFR thermal-hydraulic experiments

    International Nuclear Information System (INIS)

    Schlueter, G.; Baxi, C.B.; Dalle Donne, M.; Gat, U.; Fenech, H.; Hanson, D.; Hudina, M.

    1980-01-01

    The thermal-hydraulic experimental studies performed and planned for the Gas-Cooled Fast Reactor (GCFR) core assemblies are described. The experiments consist of basic studies performed to obtain correlations, and bundle experiments which provide input for code validation and design verification. These studies have been performed and are planned at European laboratories, US national laboratories, Universities in the US, and at General Atomic Company

  16. 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.

  17. 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

  18. DETERMINING OF THERMAL STABILITY OF EXPLOSIVES FOR CIVIL USES MODERN EQUIPMENT EQUIPPED WITH AUTOMATIC TEMPERATURE AND PRESSURE

    Directory of Open Access Journals (Sweden)

    Gabriel VASILESCU

    2015-07-01

    Full Text Available Thermal stability of explosives for civil use is a key security parameter. When the explosive is exposed to high tempera-tures in a given period of time can lead to undesirable phenomena such as decomposing or even very dangerous as un-controlled detonation.

  19. Disappearance of criticality in branched-chain thermal explosion with heat loss

    International Nuclear Information System (INIS)

    Okoya, Samuel S.

    2003-09-01

    In the framework of the currently developed branched-chain thermal explosion theory, the equation governing leakage through a hole of a reaction vessel is given. The critical ignition, extinction and transition temperature excess, activation energy parameter and modified Semenov's number are estimated employing this equation. We calculated numerically and obtained analytically these non-dimensional parameters with and without initiation respectively. The similar solution for Semenov model appear as a limiting case of our solution. We also obtained the ignition times. (author)

  20. 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)

  1. Influence of variable heat transfer coefficient of fireworks and crackers on thermal explosion critical ambient temperature and time to ignition

    Directory of Open Access Journals (Sweden)

    Guo Zerong

    2016-01-01

    Full Text Available To study the effect of variable heat transfer coefficient of fireworks and crackers on thermal explosion critical ambient temperature and time to ignition, considering the heat transfer coefficient as the power function of temperature, mathematical thermal explosion steady state and unsteady-state model of finite cylindrical fireworks and crackers with complex shell structures are established based on two-dimensional steady state thermal explosion theory. The influence of variable heat transfer coefficient on thermal explosion critical ambient temperature and time to ignition are analyzed. When heat transfer coefficient is changing with temperature and in the condition of natural convection heat transfer, critical ambient temperature lessen, thermal explosion time to ignition shorten. If ambient temperature is close to critical ambient temperature, the influence of variable heat transfer coefficient on time to ignition become large. For firework with inner barrel in example analysis, the critical ambient temperature of propellant is 463.88 K and the time to ignition is 4054.9s at 466 K, 0.26 K and 450.8s less than without considering the change of heat transfer coefficient respectively. The calculation results show that the influence of variable heat transfer coefficient on thermal explosion time to ignition is greater in this example. Therefore, the effect of variable heat transfer coefficient should be considered into thermal safety evaluation of fireworks to reduce potential safety hazard.

  2. 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.

  3. Thermal energy management process experiment

    Science.gov (United States)

    Ollendorf, S.

    1984-01-01

    The thermal energy management processes experiment (TEMP) will demonstrate that through the use of two-phase flow technology, thermal systems can be significantly enhanced by increasing heat transport capabilities at reduced power consumption while operating within narrow temperature limits. It has been noted that such phenomena as excess fluid puddling, priming, stratification, and surface tension effects all tend to mask the performance of two-phase flow systems in a 1-g field. The flight experiment approach would be to attack the experiment to an appropriate mounting surface with a 15 to 20 meter effective length and provide a heat input and output station in the form of heaters and a radiator. Using environmental data, the size, location, and orientation of the experiment can be optimized. The approach would be to provide a self-contained panel and mount it to the STEP through a frame. A small electronics package would be developed to interface with the STEP avionics for command and data handling. During the flight, heaters on the evaporator will be exercised to determine performance. Flight data will be evaluated against the ground tests to determine any anomalous behavior.

  4. mathematical model of thermal explosion, the dual variational formulation of nonlinear problem, alternative functional

    Directory of Open Access Journals (Sweden)

    V. S. Zarubin

    2016-01-01

    Full Text Available A temperature state of the solid body may depend both on the conditions of heat exchange with external environment surrounding its surface and on the energy release within the body volume, caused, for example, by the processes in nuclear reactor elements or exothermic chemical reactions, absorption of penetrating radiation energy or transformation of a part of the electrical power into heat with flowing electric current (so-called Joule heat.If with growing temperature the intensity of bulk power density increases, a limited steady temperature state can emerge at which heat extracted to the body surface and released within its volume reaches maximum. Thus, small increments of temperature lead to an increase of heat release, which can not be extracted to the body surface by conduction without further temperature increase. As a result, the steady temperature distribution in the body becomes impossible that determines the state of the thermal explosion, so named due to the fact that in this case the appropriate mathematical model predicts an unlimited temperature increase.A lot of published papers and monographs concerning the study of the combustion and explosion processes in a stationary medium analyse the thermal explosion state. The most famous papers consider a mathematical model to describe a temperature distribution in the case when heat release is because of exothermic chemical reactions the rate of which increases with temperature growth. The dependence of the chemical reaction rate on temperature is usually described by the exponential Arrhenius law, which makes it necessary to consider an essentially nonlinear mathematical model containing differential equation, which includes the term, nonlinearly rising with increasing temperature. Even with simplifying assumptions, this model allows an exact closed form solution only in the case of one-dimensional temperature distributions in the two areas of the canonical form: in the plate, infinite

  5. Thermal explosion analysis of methyl ethyl ketone peroxide by non-isothermal and isothermal calorimetric applications

    International Nuclear Information System (INIS)

    Chi, Jen-Hao; Wu, Sheng-Hung; Shu, Chi-Min

    2009-01-01

    In the past, process incidents attributed to organic peroxides (OPs) that involved near misses, over-pressures, runaway reactions, and thermal explosions occurred because of poor training, human error, incorrect kinetic assumptions, insufficient change management, and inadequate chemical knowledge in the manufacturing process. Calorimetric applications were employed broadly to test organic peroxides on a small-scale because of their thermal hazards, such as exothermic behavior and self-accelerating decomposition in the laboratory. In essence, methyl ethyl ketone peroxide (MEKPO) is highly reactive and exothermically unstable. In recent years, it has undergone many thermal explosions and runaway reaction incidents in the manufacturing process. Differential scanning calorimetry (DSC), vent sizing package 2 (VSP2), and thermal activity monitor (TAM) were employed to analyze thermokinetic parameters and safety index. The intent of the analyses was to facilitate the use of various auto-alarm equipments to detect over-pressure, over-temperature, and hazardous materials leaks for a wide spectrum of operations. Results indicated that MEKPO decomposition is detected at low temperatures (30-40 deg. C), and the rate of decomposition was shown to exponentially increase with temperature and pressure. Determining time to maximum rate (TMR), self-accelerating decomposition temperature (SADT), maximum temperature (T max ), exothermic onset temperature (T 0 ), and heat of decomposition (ΔH d ) was essential for identifying early-stage runaway reactions effectively for industries.

  6. Pressurized-thermal-shock experiments

    International Nuclear Information System (INIS)

    Whitman, G.D.; McCulloch, R.W.

    1982-01-01

    The primary objective of the ORNL pressurized-thermal-shock (PTS) experiments is to verify analytical methods that are used to predict the behavior of pressurized-water-reactor vessels under these accident conditions involving combined pressure and thermal loading. The criteria on which the experiments are based are: scale large enough to attain effective flaw border triaxial restraint and a temperature range sufficiently broad to produce a progression from frangible to ductile behavior through the wall at a given time; use of materials that can be completely characterized for analysis; stress states comparable to the actual vessel in zones of potential flaw extension; range of behavior to include cleavage initiation and arrest, cleavage initiation and arrest on the upper shelf, arrest in a high K/sub I/ gradient, warm prestressing, and entirely ductile behavior; long and short flaws with and without stainless steel cladding; and control of loads to prevent vessel burst, except as desired. A PTS test facility is under construction which will enable the establishment and control of wall temperature, cooling rate, and pressure on an intermediate test vessel (ITV) in order to simulate stress states representative of an actual reactor pressure vessel

  7. Reliability analysis for thermal cutting method based non-explosive separation device

    International Nuclear Information System (INIS)

    Choi, Jun Woo; Hwang, Kuk Ha; Kim, Byung Kyu

    2016-01-01

    In order to increase the reliability of a separation device for a small satellite, a new non-explosive separation device is invented. This device is activated using a thermal cutting method with a Ni-Cr wire. A reliability analysis is carried out for the proposed non-explosive separation device by applying the Fault tree analysis (FTA) method. In the FTA results for the separation device, only ten single-point failure modes are found. The reliability modeling and analysis for the device are performed considering failure of the power supply, the Ni-Cr wire burns failure and unwinds, the holder separation failure, the balls separation failure, and the pin release failure. Ultimately, the reliability of the proposed device is calculated as 0.999989 with five Ni-Cr wire coils

  8. Thermal chemical-mechanical reactive flow model of shock initiation in solid explosives

    International Nuclear Information System (INIS)

    Nicholls, A.L. III; Tarver, C.M.

    1998-01-01

    The three dimensional Arbitrary Lagrange Eulerian hydrodynamic computer code ALE3D with fully coupled thermal-chemical-mechanical material models provides the framework for the development of a physically realistic model of shock initiation and detonation of solid explosives. The processes of hot spot formation during shock compression, subsequent ignition of reaction or failure to react, growth of reaction in individual hot spots, and coalescence of reacting hot spots during the transition to detonation can now be modeled using Arrhenius chemical kinetic rate laws and heat transfer to propagate the reactive flow. This paper discusses the growth rates of reacting hot spots in HMX and TATB and their coalescence during shock to detonation transition. Hot spot deflagration rates are found to be fast enough to consume explosive particles less than 10 mm in diameter during typical shock duration times, but larger particles must fragment and create more reactive surface area in order to be rapidly consumed

  9. Reliability analysis for thermal cutting method based non-explosive separation device

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jun Woo; Hwang, Kuk Ha; Kim, Byung Kyu [Korea Aerospace University, Goyang (Korea, Republic of)

    2016-12-15

    In order to increase the reliability of a separation device for a small satellite, a new non-explosive separation device is invented. This device is activated using a thermal cutting method with a Ni-Cr wire. A reliability analysis is carried out for the proposed non-explosive separation device by applying the Fault tree analysis (FTA) method. In the FTA results for the separation device, only ten single-point failure modes are found. The reliability modeling and analysis for the device are performed considering failure of the power supply, the Ni-Cr wire burns failure and unwinds, the holder separation failure, the balls separation failure, and the pin release failure. Ultimately, the reliability of the proposed device is calculated as 0.999989 with five Ni-Cr wire coils.

  10. Investigation of coal dust explosion hazard at the Nikola Tesla-A thermal power station

    Energy Technology Data Exchange (ETDEWEB)

    Golubovic, D

    1987-10-01

    Reports on investigations into coal dust explosion hazards in working places with high coal dust exposure, done in the Tesla-A thermal power station by Mining Institute of Belgrade specialists. Settled and floating coal dust concentrations were monitored for six months and samples analyzed for explosibility under lab conditions. Samples from transport and preparation facilities and the power station boiler house were taken. The entire plant was divided into 4 zones, depending on intensity of dust settlement and ventilation system. Coal dust generation varied from 0.3-65 g/min. Daily dust settlement ranged between 40 and 300 g/m/sup 2/. Total quantity of accumulated coal dust in the power plant ranged from 0.8-650 kg/day; 250 g/m/sup 3/ of coal dust may cause an explosion. Thus, a dangerous amount of coal dust, depending on work-site, will settle in 3.3.-21.8 days. Disturbance of settled dust may create explodable clouds. Details of measurements taken and data evaluation are included. 4 refs.

  11. DHS small-scale safety and thermal testing of improvised explosives-comparison of testing performance

    International Nuclear Information System (INIS)

    Reynolds, J G; Hsu, P C; Sandstrom, M M; Brown, G W; Warner, K F; Phillips, J J; Shelley, T J; Reyes, J A

    2014-01-01

    One of the first steps in establishing safe handling procedures for explosives is small-scale safety and thermal (SSST) testing. To better understand the response of improvised materials or homemade explosives (HMEs) to SSST testing, 16 HME materials were compared to three standard military explosives in a proficiency-type round robin study among five laboratories-two DoD and three DOE-sponsored by DHS. The testing matrix has been designed to address problems encountered with improvised materials-powder mixtures, liquid suspensions, partially wetted solids, immiscible liquids, and reactive materials. More than 30 issues have been identified that indicate standard test methods may require modification when applied to HMEs to derive accurate sensitivity assessments needed for developing safe handling and storage practices. This paper presents a generalized comparison of the results among the testing participants, comparison of friction results from BAM (German Bundesanstalt für Materi-alprüfung) and ABL (Allegany Ballistics Laboratory) designed testing equipment, and an overview of the statistical results from the RDX (1,3,5-Trinitroperhydro-1,3,5-triazine) standard tested throughout the proficiency test.

  12. Improve the Anaerobic Biodegradability by Copretreatment of Thermal Alkali and Steam Explosion of Lignocellulosic Waste

    Directory of Open Access Journals (Sweden)

    Muhammad Abdul Hanan Siddhu

    2016-01-01

    Full Text Available Effective alteration of the recalcitrance properties like crystallization of cellulose, lignin shield, and interlinking of lignocellulosic biomass is an ideal way to utilize the full-scale potential for biofuel production. This study exhibited three different pretreatment effects to enhance the digestibility of corn stover (CS for methane production. In this context, steam explosion (SE and thermal potassium hydroxide (KOH-60°C treated CS produced the maximal methane yield of 217.5 and 243.1 mL/gvs, which were 40.0% and 56.4% more than untreated CS (155.4 mL/gvs, respectively. Copretreatment of thermal potassium hydroxide and steam explosion (CPTPS treated CS was highly significant among all treatments and improved 88.46% (292.9 mL/gvs methane yield compared with untreated CS. Besides, CPTPS also achieved the highest biodegradability up to 68.90%. Three kinetic models very well simulated dynamics of methane production yield. Moreover, scanning electron microscopy (SEM, Fourier transform infrared (FTIR, and X-ray diffraction (XRD analyses declared the most effective changes in physicochemical properties after CPTPS pretreatment. Thus, CPTPS might be a promising approach to deconstructing the recalcitrance of lignocellulosic structure to improve the biodegradability for AD.

  13. 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.

  14. Modeling the thermal deformation of TATB-based explosives. Part 1: Thermal expansion of “neat-pressed” polycrystalline TATB

    Energy Technology Data Exchange (ETDEWEB)

    Luscher, Darby J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-05-08

    We detail a modeling approach to simulate the anisotropic thermal expansion of polycrystalline (1,3,5-triamino-2,4,6-trinitrobenzene) TATB-based explosives that utilizes microstructural information including porosity, crystal aspect ratio, and processing-induced texture. This report, the first in a series, focuses on nonlinear thermal expansion of “neat-pressed” polycrystalline TATB specimens which do not contain any binder; additional complexities related to polymeric binder and irreversible ratcheting behavior are briefly discussed, however detailed investigation of these aspects are deferred to subsequent reports. In this work we have, for the first time, developed a mesoscale continuum model relating the thermal expansion of polycrystal TATB specimens to their microstructural characteristics. A self-consistent homogenization procedure is used to relate macroscopic thermoelastic response to the constitutive behavior of single-crystal TATB. The model includes a representation of grain aspect ratio, porosity, and crystallographic texture attributed to the consolidation process. A quantitative model is proposed to describe the evolution of preferred orientation of graphitic planes in TATB during consolidation and an algorithm constructed to develop a discrete representation of the associated orientation distribution function. Analytical and numerical solutions using this model are shown to produce textures consistent with previous measurements and characterization for isostatic and uniaxial “die-pressed” specimens. Predicted thermal strain versus temperature for textured specimens are shown to be in agreement with corresponding experimental measurements. Using the developed modeling approach, several simulations have been run to investigate the influence of microstructure on macroscopic thermal expansion behavior. Results from these simulations are used to identify qualitative trends. Implications of the identified trends are discussed in the context of

  15. Direct Observation of the Phenomenology of a Solid Thermal Explosion Using Time-Resolved Proton Radiography

    International Nuclear Information System (INIS)

    Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.; Schwartz, C. L.; Saunders, A.; Merrill, F. E.; Morris, C. L.; Kwiatkowski, K.; Hogan, G.; Nedrow, P.; Murray, M. M.; Thompson, T. N.; McNeil, W.; Rightley, P.; Marr-Lyon, M.

    2008-01-01

    We present a new phenomenology for burn propagation inside a thermal explosion based on dynamic radiography. Radiographic images were obtained of an aluminum cased solid cylindrical sample of a plastic bonded formulation of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine. The phenomenology observed is ignition followed by cracking in the solid accompanied by the propagation of a radially symmetric front of increasing proton transmission. This is followed by a further increase in transmission through the sample, ending after approximately 100 μs. We show that these processes are consistent with the propagation of a convective burn front followed by consumption of the remaining solid by conductive particle burning

  16. Study on Thermal Decomposition Characteristics of Ammonium Nitrate Emulsion Explosive in Different Scales

    Science.gov (United States)

    Wu, Qiujie; Tan, Liu; Xu, Sen; Liu, Dabin; Min, Li

    2018-04-01

    Numerous accidents of emulsion explosive (EE) are attributed to uncontrolled thermal decomposition of ammonium nitrate emulsion (ANE, the intermediate of EE) and EE in large scale. In order to study the thermal decomposition characteristics of ANE and EE in different scales, a large-scale test of modified vented pipe test (MVPT), and two laboratory-scale tests of differential scanning calorimeter (DSC) and accelerating rate calorimeter (ARC) were applied in the present study. The scale effect and water effect both play an important role in the thermal stability of ANE and EE. The measured decomposition temperatures of ANE and EE in MVPT are 146°C and 144°C, respectively, much lower than those in DSC and ARC. As the size of the same sample in DSC, ARC, and MVPT successively increases, the onset temperatures decrease. In the same test, the measured onset temperature value of ANE is higher than that of EE. The water composition of the sample stabilizes the sample. The large-scale test of MVPT can provide information for the real-life operations. The large-scale operations have more risks, and continuous overheating should be avoided.

  17. Thermal explosion hazards on 18650 lithium ion batteries with a VSP2 adiabatic calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Jhu, Can-Yong [Doctoral Program, Graduate School of Engineering Science and Technology, National Yunlin University of Science and Technology (NYUST), 123, University Rd., Sec. 3, Douliou, Yunlin 64002, Taiwan, ROC (China); Wang, Yih-Wen, E-mail: g9410825@yuntech.edu.tw [Department of Occupational Safety and Health, Jen-Teh Junior College of Medicine, Nursing and Management, 79-9, Sha-Luen-Hu, Xi-Zhou-Li, Houlong, Miaoli 35664, Taiwan, ROC (China); Shu, Chi-Min [Doctoral Program, Graduate School of Engineering Science and Technology, National Yunlin University of Science and Technology (NYUST), 123, University Rd., Sec. 3, Douliou, Yunlin 64002, Taiwan, ROC (China); Chang, Jian-Chuang; Wu, Hung-Chun [Material and Chemical Research Laboratories, Industrial Technology Research Institute (ITRI), Rm. 222, Bldg. 77, 2F, 195, Sec. 4, Chung Hsing Rd., Chutung, Hsinchu 31040, Taiwan, ROC (China)

    2011-08-15

    Thermal abuse behaviors relating to adiabatic runaway reactions in commercial 18650 lithium ion batteries (LiCoO{sub 2}) are being studied in an adiabatic calorimeter, vent sizing package 2 (VSP2). We select four worldwide battery producers, Sony, Sanyo, Samsung and LG, and tested their Li-ion batteries, which have LiCoO{sub 2} cathodes, to determine their thermal instabilities and adiabatic runaway features. The charged (4.2 V) and uncharged (3.7 V) 18650 Li-ion batteries are tested using a VSP2 with a customized stainless steel test can to evaluate their thermal hazard characteristics, such as the initial exothermic temperature (T{sub 0}), the self-heating rate (dT/dt), the pressure rise rate (dP/dt), the pressure-temperature profiles and the maximum temperature (T{sub max}) and pressure (P{sub max}). The T{sub max} and P{sub max} of the charged Li-ion battery during the runaway reaction reach 903.0 {sup o}C and 1565.9 psig (pound-force per square inch gauge), respectively. This result leads to a thermal explosion, and the heat of reaction is 26.2 kJ. The thermokinetic parameters of the reaction of LiCoO{sub 2} batteries are also determined using the Arrhenius model. The thermal reaction mechanism of the Li-ion battery (pack) proved to be an important safety concern for energy storage. Additionally, use of the VSP2 to classify the self-reactive ratings of the various Li-ion batteries demonstrates a new application of the adiabatic calorimetric methodology.

  18. Thermal explosion hazards on 18650 lithium ion batteries with a VSP2 adiabatic calorimeter

    International Nuclear Information System (INIS)

    Jhu, Can-Yong; Wang, Yih-Wen; Shu, Chi-Min; Chang, Jian-Chuang; Wu, Hung-Chun

    2011-01-01

    Thermal abuse behaviors relating to adiabatic runaway reactions in commercial 18650 lithium ion batteries (LiCoO 2 ) are being studied in an adiabatic calorimeter, vent sizing package 2 (VSP2). We select four worldwide battery producers, Sony, Sanyo, Samsung and LG, and tested their Li-ion batteries, which have LiCoO 2 cathodes, to determine their thermal instabilities and adiabatic runaway features. The charged (4.2 V) and uncharged (3.7 V) 18650 Li-ion batteries are tested using a VSP2 with a customized stainless steel test can to evaluate their thermal hazard characteristics, such as the initial exothermic temperature (T 0 ), the self-heating rate (dT/dt), the pressure rise rate (dP/dt), the pressure-temperature profiles and the maximum temperature (T max ) and pressure (P max ). The T max and P max of the charged Li-ion battery during the runaway reaction reach 903.0 o C and 1565.9 psig (pound-force per square inch gauge), respectively. This result leads to a thermal explosion, and the heat of reaction is 26.2 kJ. The thermokinetic parameters of the reaction of LiCoO 2 batteries are also determined using the Arrhenius model. The thermal reaction mechanism of the Li-ion battery (pack) proved to be an important safety concern for energy storage. Additionally, use of the VSP2 to classify the self-reactive ratings of the various Li-ion batteries demonstrates a new application of the adiabatic calorimetric methodology.

  19. 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)

  20. YALINA-Thermal Facility Experiments

    International Nuclear Information System (INIS)

    Kiyavitskaya, H.; Bournos, V.; Fokov, Y.; Routkovskaya, C.; Sadovich, S.; Cintas, A.; Márquez Damián, J.I.; Lopasso, E.M.; Maiorino, J.R.; Carluccio, T.; Rossi, P.C.R.; Antunes, A.; Oliveira, F.L. de; Lee, S.M.; Xia, P.; Shi, Y.; Xia, H.; Zhu, Q.; Yu, T.; Wu, X.; Zhang, W.; Cao, J.; Luo, H.; Quan, Y.; Kulkarni, K.; Yadav, R.D.S.; Bajpai, A.; Degweker, S.B.; Modak, R.S.; Park, H.J.; Shim, H.J.; Kim, C.H.; Wojciechowski, A.; Zuta, M.; Pešić, M.; Avramović, I.; Beličev, P.; Gohar, Y.; Talamo, A.; Aliberti, G.

    2017-01-01

    This Section discussed the results obtained by the Member States participating in the IAEA coordinated research project on Analytical and Experimental Benchmark Analysis on Accelerator Driven Systems, and Low Enriched Uranium Fuel Utilization in Accelerator Driven Subcritical Assembly Systems for the YALINA Thermal facility. Member States used both Monte Carlo and deterministic computational tools to analyse the YALINA Thermal subcritical assembly, including: MCNP5, MCNPX, McCARD, PARTISN, and ERANOS computer programs. All calculations have been performed using the ENDF/B-VI (different modes) nuclear data libraries with the exception of Republic of Korea which used the ENDF/B-VII.0 nuclear data library. Generally, there is a good agreement between the results obtained by all the Member States. Deterministic codes perform space, energy, and angle discretization and materials homogenizations, which introduce approximations affecting the obtained results. In subcritical assemblies, the neutron multiplication and the detector counting rate depend strongly on the external neutron source. Cf and D-D sources provide similar results since they emit neutrons with similar average energy. D-T neutrons trigger (n,xn) reactions and have a longer mean free path, which increases the neutron leakage if the geometry dimensions of the assembly are small, as in the case of the YALINA-Thermal subcritical assembly. Close to criticality, the effect of the external neutron source diminishes since fission neutrons dominate the neutron population.

  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. 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)

  3. Thermal-hydraulics of wave propagation and pressure distribution under hypothetical steam explosion conditions in the ANS reactor

    Energy Technology Data Exchange (ETDEWEB)

    Taleyarkhan, R.P.; Georgevich, V.; N-Valenit, S.; Kim, S.H. [Oak Ridge National Lab., TN (United States)

    1995-09-01

    This paper describes salient aspects of the modeling and analysis framework for evaluation of dynamic loads, wave propagation, and pressure distributions (under hypothetical steam explosion conditions) around key structural boundaries of the Advanced Neutron Source (ANS) reactor core region. A staged approach was followed, using simple thermodynamic models for bounding loads and the CTH code for evaluating realistic estimates in a staged multidimensional framework. Effects of nodalization, melt dispersal into coolant during explosion, single versus multidirectional dissipation, energy level of melt, and rate of energy deposition into coolant were studied. The importance of capturing multidimensional effects that simultaneously account for fluid-structural interactions was demonstrated. As opposed to using bounding loads from thermodynamic evaluations, it was revealed that the ANS reactor system will not be vulnerable to vertically generated missiles that threaten containment if realistic estimates of energetics are used (from CTH calculations for thermally generated steam explosions without significant aluminum ignition).

  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. Observations of Tin/Water Thermal Explosions in a Long-Tube Geometry. Their Interpretation and Consequences for the Detonation Model

    International Nuclear Information System (INIS)

    Hall, R.W.; Board, S.J.; Baines, M.

    1979-01-01

    This paper presents details of experiments designed to test the detonation model of thermal explosions (Board et al, 1975); on this theory large-scale explosions should propagate steadily at supersonic velocities through a fuel coolant mixture, giving a yield which has been shown to depend on details of the fragmentation and heat transfer behind the shock front. Observations of propagating explosions have been reported previously. In the present work, a long-tube geometry is used since in 1D, propagation measurements are particularly easy to interpret. Also, in 2D and 3D geometries radial flow can tend to extinguish shock waves and if a single-phase region of coolant is present, pressure pulses can propagate ahead of the two-phase shock in the intermixed region. This paper describes the six experiments that all use molten tin and water mixtures. In the first four, detailed pressure measurement was the main objective; the last two are attempts at flow visualization to aid the interpretation of these. The results obtained and the implications for the detonation model are discussed. A detailed interpretation in terms of fragmentation and heat transfer processes behind the shock is attempted. The implications of the work for reactor materials are then briefly outlined

  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. Preliminary analysis of K-DEMO thermal hydraulic system using MELCOR; Parametric study of hydrogen explosion

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Sung Bo; Lim, Soo Min; Bang, In Cheol [UNIST, Ulsan (Korea, Republic of)

    2016-10-15

    K-DEMO (Korean fusion demonstration reactor) is future reactor for the commercializing the fusion power generation. The Design of K-DEMO is similar to that of ITER but the fusion energy generation is much bigger because ITER is experimental reactor. For this reason, K-DEMO uses more fusion reaction with bigger amount of tritium. Higher fusion power means more neutron generation that can irradiate the structure around fusion plasma. Fusion reactor can produce many kinds of radioactive material in the accident. Because of this hazard, preliminary safety analysis is mandatory before its construction. Concern for safety problem of accident of fusion/fission reactor has been growing after Fukushima accident which is severe accident from unexpected disaster. To model the primary heat transfer system, in this study, MARS-KS thermal hydraulic analysis is referred. Lee et al. and Kim et al. conducted thermal hydraulic analysis using MARS-KS and multiple module simulation to deal with the phenomena of first wall corrosion for each plasma pulse. This study shows the relationship between vacuum vessel rupture area and source term leakage after hydrogen explosion. For the conservative study, first wall heating is not terminated because the heating inside the vacuum vessel increase the pressure inside VV. Pressurizer, steam generator and turbine is not damaged. 6.69 kg of tritiated water (HTO) and 1 ton of dust is modeled which is ITER guideline. The entire system of K-DEMO is smaller than that of ITER. For this reason, lots of aerosol is release into environment although the safety system like DS is maintained. This result shows that the safety system of K-DEMO should use much more safety system.

  9. The surface quasiliquid melt acceleration and the role of thermodynamic phase in the thermal decomposition of crystalline organic explosives

    Energy Technology Data Exchange (ETDEWEB)

    Henson, Bryan F [Los Alamos National Laboratory

    2010-01-01

    We show that melt acceleration in the thermal decomposition of crystalline organic solids is a manifestation of the surface quasiliquid phase. We derive a single universal rate law for melt acceleration that is a simple function of the metastable liquid activity below the melting point, and has a zero order term proportional to the quasiliquid thickness. We argue that the underlying mechanisms of this model will provide a molecular definition for the stability of the class of secondary explosives.

  10. Comparison of the Effects of Thermal Pretreatment, Steam Explosion and Ultrasonic Disintegration on Digestibility of Corn Stover

    OpenAIRE

    Andras Dallos; Gyula Dörgő; Dániel Capári

    2016-01-01

    The energy demand of the corn-based bioethanol production could be reduced using the agricultural byproducts as bioenergy feedstock for biogas digesters. The release of lignocellulosic material and therefore the acceleration of degradation processes can be achieved using thermal and mechanical pretreatments, which assist to hydrolyze the cell walls and speed the solubilization of biopolymers in biogas feedstock. This study is focused on liquid hot water, steam explosion and ultrasonic pretrea...

  11. 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

  12. Plasma thermal energy transport: theory and experiments

    International Nuclear Information System (INIS)

    Coppi, B.

    Experiments on the transport across the magnetic field of electron thermal energy are reviewed (Alcator, Frascati Torus). In order to explain the experimental results, a transport model is described that reconfirmed the need to have an expression for the local diffusion coefficient with a negative exponent of the electron temperature

  13. Use of artificial neural networks in drug and explosive detection through tomographic images with thermal neutrons

    International Nuclear Information System (INIS)

    Ferreira, Francisco J.O.; Crispim, Verginia R.; Silva, Ademir X.

    2009-01-01

    The artificial neural network technique was used to identify drugs and plastic explosives, from a tomography composed by a set of six neutrongraphic projections obtained in real time. Bidimensional tomographic images of samples of drugs, explosives and other materials, when digitally processed, yield the characteristic spectra of each type of material. The information contained in those spectra was then used for ANN training, the best images being obtained when the multilayer perceptron model, the back-propagation training algorithm and the Cross-validation interruption criterion were used. ANN showed to be useful in forecasting presence of drugs and explosives hitting a rate of success above 97 %. (author)

  14. Comparison of the Effects of Thermal Pretreatment, Steam Explosion and Ultrasonic Disintegration on Digestibility of Corn Stover

    Directory of Open Access Journals (Sweden)

    Andras Dallos

    2016-06-01

    Full Text Available The energy demand of the corn-based bioethanol production could be reduced using the agricultural byproducts as bioenergy feedstock for biogas digesters. The release of lignocellulosic material and therefore the acceleration of degradation processes can be achieved using thermal and mechanical pretreatments, which assist to hydrolyze the cell walls and speed the solubilization of biopolymers in biogas feedstock. This study is focused on liquid hot water, steam explosion and ultrasonic pretreatments of corn stover. The scientific contribution of this paper is a comprehensive comparison of the performance of the pretreatments by fast analytical, biochemical, anaerobic digestibility and biomethane potential tests, extended by energy consumptions and energy balance calculations.The effectiveness of pretreatments was evaluated by means of soluble chemical oxygen demand, biochemical oxygen demand and by the biogas and methane productivities. The results have shown that the thermal pretreatment, steam explosion and ultrasonic irradiation of biogas feedstock disintegrated the lignocellulosic structure, increased and accelerated the methane production and increased the cumulative biogas and methane productivity of corn stover in reference to the control during mesophilic anaerobic digestion.The energy balance demonstrated that there is an economical basis of the application of the liquid hot-compressed water pretreatments in a biogas plant. However, the steam explosion and ultrasonication are energetically not profitable for corn stover pretreatment.

  15. Analysis of the thermal fragmentation as a mechanism for the initiation of steam explosion

    International Nuclear Information System (INIS)

    Lamome, J.; Meignen, R.

    2007-01-01

    We propose a theoretical study of the film behaviour and its stability during the phenomenon of drop thermal fragmentation. We discuss the role of the various possible influences on the film collapse and instability processes. First, we discuss the possibility of simple fuel/coolant contacts as a mechanism for the drop instability. Under this assumption, we then describe and test our model on Nelson and Duda explodability maps, with a particular emphasis on the description of the film evolution. The reasonable agreement obtained allows us to analyse the effect of various parameters as the ambient pressure, subcooling and trigger pulse shape on the film behaviour in Nelson and Duda experiments. The perspectives of this work are then shortly discussed including extrapolation to more prototypic situations and the role of thermal fragmentation itself. (authors)

  16. Rapid thermal process by RF heating of nano-graphene layer/silicon substrate structure: Heat explosion theory approach

    Science.gov (United States)

    Sinder, M.; Pelleg, J.; Meerovich, V.; Sokolovsky, V.

    2018-03-01

    RF heating kinetics of a nano-graphene layer/silicon substrate structure is analyzed theoretically as a function of the thickness and sheet resistance of the graphene layer, the dimensions and thermal parameters of the structure, as well as of cooling conditions and of the amplitude and frequency of the applied RF magnetic field. It is shown that two regimes of the heating can be realized. The first one is characterized by heating of the structure up to a finite temperature determined by equilibrium between the dissipated loss power caused by induced eddy-currents and the heat transfer to environment. The second regime corresponds to a fast unlimited temperature increase (heat explosion). The criterions of realization of these regimes are presented in the analytical form. Using the criterions and literature data, it is shown the possibility of the heat explosion regime for a graphene layer/silicon substrate structure at RF heating.

  17. Detection of Nonvolatile Inorganic Oxidizer-Based Explosives from Wipe Collections by Infrared Thermal Desorption-Direct Analysis in Real Time Mass Spectrometry.

    Science.gov (United States)

    Forbes, Thomas P; Sisco, Edward; Staymates, Matthew

    2018-05-07

    Infrared thermal desorption (IRTD) was coupled with direct analysis in real time mass spectrometry (DART-MS) for the detection of both inorganic and organic explosives from wipe collected samples. This platform generated discrete and rapid heating rates that allowed volatile and semivolatile organic explosives to thermally desorb at relatively lower temperatures, while still achieving elevated temperatures required to desorb nonvolatile inorganic oxidizer-based explosives. IRTD-DART-MS demonstrated the thermal desorption and detection of refractory potassium chlorate and potassium perchlorate oxidizers, compounds difficult to desorb with traditional moderate-temperature resistance-based thermal desorbers. Nanogram to sub-nanogram sensitivities were established for analysis of a range of organic and inorganic oxidizer-based explosive compounds, with further enhancement limited by the thermal properties of the most common commercial wipe materials. Detailed investigations and high-speed visualization revealed conduction from the heated glass-mica base plate as the dominant process for heating of the wipe and analyte materials, resulting in thermal desorption through boiling, aerosolization, and vaporization of samples. The thermal desorption and ionization characteristics of the IRTD-DART technique resulted in optimal sensitivity for the formation of nitrate adducts with both organic and inorganic species. The IRTD-DART-MS coupling and IRTD in general offer promising explosive detection capabilities to the defense, security, and law enforcement arenas.

  18. 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.

  19. Thermal-Hydraulic Experiment Facility (THEF)

    International Nuclear Information System (INIS)

    Martinell, J.S.

    1982-01-01

    This paper provides an overview of the Thermal-Hydraulic Experiment Facility (THEF) at the Idaho National Engineering Laboratory (INEL). The overview describes the major test systems, measurements, and data acquisition system, and presents objectives, facility configuration, and results for major experimental projects recently conducted at the THEF. Plans for future projects are also discussed. The THEF is located in the Water Reactor Research Test Facility (WRRTF) area at the INEL

  20. TMX-U thermal-barrier experiments

    International Nuclear Information System (INIS)

    Simonen, T.C.; Allen, S.L.; Barter, J.D.

    1988-01-01

    This review of thermal-barrier experiments in the Tandem Mirror Experiment Upgrade (TMX-U) describes our progress at Lawrence Livermore National Laboratory in plasma confinement and central-cell heating. Thermal barriers in TMX-U improved axial confinement by two orders of magnitude over a limited range of densities, compared with confinement in single-cell mirrors at the same ion temperature. Our study shows that central-cell radial nonambipolar confinement scales as neoclassical theory and can be eliminated by floating the end walls. Radial ambipolar losses can also be measured and reduced. The electron energy balance is improved in tandem mirrors to near classical, resulting in T/sub e/ up to 0.28 keV. Electron cyclotron heating (ECH) efficiencies up to 42 percent, with low levels of electron microinstability, were achieved when hot electrons in the thermal barrier were heated to average betas as large as 15 percent. The hot-electron distribution is measured from X rays and is modeled by a Fokker-Planck code that includes heating from cavity radio-frequency (RF) fields. Neutral-beam injection in the central cell created average ion betas up to 5 percent with radial profiles of hot ions that are modeled accurately by a radial Fokker-Planck code. Gas fueling between two fundamental ion cyclotron heating (ICH) resonances resulted in symmetrical heating of passing ions toward both ends

  1. Operational Experience from Solar Thermal Energy Projects

    Science.gov (United States)

    Cameron, C. P.

    1984-01-01

    Over the past few years, Sandia National Laboratories were involved in the design, construction, and operation of a number of DOE-sponsored solar thermal energy systems. Among the systems currently in operation are several industrial process heat projects and the Modular Industrial Solar Retrofit qualification test systems, all of which use parabolic troughs, and the Shenandoah Total Energy Project, which uses parabolic dishes. Operational experience has provided insight to both desirable and undesirable features of the designs of these systems. Features of these systems which are also relevant to the design of parabolic concentrator thermal electric systems are discussed. Other design features discussed are system control functions which were found to be especially convenient or effective, such as local concentrator controls, rainwash controls, and system response to changing isolation. Drive systems are also discussed with particular emphasis of the need for reliability and the usefulness of a manual drive capability.

  2. Argonne Bubble Experiment Thermal Model Development III

    Energy Technology Data Exchange (ETDEWEB)

    Buechler, Cynthia Eileen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-11

    This report describes the continuation of the work reported in “Argonne Bubble Experiment Thermal Model Development” and “Argonne Bubble Experiment Thermal Model Development II”. The experiment was performed at Argonne National Laboratory (ANL) in 2014. A rastered 35 MeV electron beam deposited power in a solution of uranyl sulfate, generating heat and radiolytic gas bubbles. Irradiations were performed at beam power levels between 6 and 15 kW. Solution temperatures were measured by thermocouples, and gas bubble behavior was recorded. The previous report2 described the Monte-Carlo N-Particle (MCNP) calculations and Computational Fluid Dynamics (CFD) analysis performed on the as-built solution vessel geometry. The CFD simulations in the current analysis were performed using Ansys Fluent, Ver. 17.2. The same power profiles determined from MCNP calculations in earlier work were used for the 12 and 15 kW simulations. The primary goal of the current work is to calculate the temperature profiles for the 12 and 15 kW cases using reasonable estimates for the gas generation rate, based on images of the bubbles recorded during the irradiations. Temperature profiles resulting from the CFD calculations are compared to experimental measurements.

  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. 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)

  6. 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)

  7. 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

  8. 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

  9. PPOOLEX experiments on thermal stratification and mixing

    Energy Technology Data Exchange (ETDEWEB)

    Puustinen, M.; Laine, J.; Raesaenen, A. (Lappeenranta Univ. of Technology, Nuclear Safety Research Unit (Finland))

    2009-08-15

    The results of the thermal stratification experiments in 2008 with the PPOOLEX test facility are presented. PPOOLEX is a closed vessel divided into two compartments, dry well and wet well. Extra temperature measurements for capturing different aspects of the investigated phenomena were added before the experiments. The main purpose of the experiment series was to generate verification data for evaluating the capability of GOTHIC code to predict stratification and mixing phenomena. Altogether six experiments were carried out. Heat-up periods of several thousand seconds by steam injection into the dry well compartment and from there into the wet well water pool were recorded. The initial water bulk temperature was 20 deg. C. Cooling periods of several days were included in three experiments. A large difference between the pool bottom and top layer temperature was measured when small steam flow rates were used. With higher flow rates the mixing effect of steam discharge delayed the start of stratification until the pool bulk temperature exceeded 50 deg. C. The stratification process was also different in these two cases. With a small flow rate stratification was observed only above and just below the blowdown pipe outlet elevation. With a higher flow rate over a 30 deg. C temperature difference between the pool bottom and pipe outlet elevation was measured. Elevations above the pipe outlet indicated almost linear rise until the end of steam discharge. During the cooling periods the measurements of the bottom third of the pool first had an increasing trend although there was no heat input from outside. This was due to thermal diffusion downwards from the higher elevations. Heat-up in the gas space of the wet well was quite strong, first due to compression by pressure build-up and then by heat conduction from the hot dry well compartment via the intermediate floor and test vessel walls and by convection from the upper layers of the hot pool water. The gas space

  10. PPOOLEX experiments on thermal stratification and mixing

    International Nuclear Information System (INIS)

    Puustinen, M.; Laine, J.; Raesaenen, A.

    2009-08-01

    The results of the thermal stratification experiments in 2008 with the PPOOLEX test facility are presented. PPOOLEX is a closed vessel divided into two compartments, dry well and wet well. Extra temperature measurements for capturing different aspects of the investigated phenomena were added before the experiments. The main purpose of the experiment series was to generate verification data for evaluating the capability of GOTHIC code to predict stratification and mixing phenomena. Altogether six experiments were carried out. Heat-up periods of several thousand seconds by steam injection into the dry well compartment and from there into the wet well water pool were recorded. The initial water bulk temperature was 20 deg. C. Cooling periods of several days were included in three experiments. A large difference between the pool bottom and top layer temperature was measured when small steam flow rates were used. With higher flow rates the mixing effect of steam discharge delayed the start of stratification until the pool bulk temperature exceeded 50 deg. C. The stratification process was also different in these two cases. With a small flow rate stratification was observed only above and just below the blowdown pipe outlet elevation. With a higher flow rate over a 30 deg. C temperature difference between the pool bottom and pipe outlet elevation was measured. Elevations above the pipe outlet indicated almost linear rise until the end of steam discharge. During the cooling periods the measurements of the bottom third of the pool first had an increasing trend although there was no heat input from outside. This was due to thermal diffusion downwards from the higher elevations. Heat-up in the gas space of the wet well was quite strong, first due to compression by pressure build-up and then by heat conduction from the hot dry well compartment via the intermediate floor and test vessel walls and by convection from the upper layers of the hot pool water. The gas space

  11. Thermal Runaways in LHC Interconnections: Experiments

    CERN Document Server

    Willering, G P; Bottura, L; Scheuerlein, C; Verweij, A P

    2011-01-01

    The incident in the LHC in September 2008 occurred in an interconnection between two magnets of the 13 kA dipole circuit. This event was traced to a defect in one of the soldered joints between two superconducting cables stabilized by a copper busbar. Further investigation revealed defective joints of other types. A combination of (1) a poor contact between the superconducting cable and the copper stabilizer and (2) an electrical discontinuity in the stabilizer at the level of the connection can lead to an unprotected quench of the busbar. Once the heating power in the unprotected superconducting cable exceeds the heat removal capacity a thermal run-away occurs, resulting in a fast melt-down of the non-stabilized cable. We have performed a thorough investigation of the conditions upon which a thermal run-away in the defect can occur. To this aim, we have prepared heavily instrumented samples with well-defined and controlled defects. In this paper we describe the experiment, and the analysis of the data, and w...

  12. Strain measurements during pressurized thermal shock experiment

    International Nuclear Information System (INIS)

    Tarso Vida Gomes, P. de; Julio Ricardo Barreto Cruz; Tanius Rodrigues Mansur; Denis Henrique Bianchi Scaldaferri; Miguel Mattar Neto

    2005-01-01

    For the life extension of nuclear power plants, the residual life of most of their components must be evaluated along all their operating time. Concerning the reactor pressure vessel, the pressurized thermal shock (PTS) is a very important event to be considered. For better understanding the effects of this kind of event, tests are made. The approach described here consisted of building a simplified in-scale physical model of the reactor pressure vessel, submitting it to the actual operating temperature and pressure conditions and provoking a thermal shock by means of cold water flow in its external surface. To conduct such test, the Nuclear Technology Development Center (CDTN) has been conducting several studies related to PTS and has also built a laboratory that has made possible the simulation of the PTS loading conditions. Several cracks were produced in the external surface of the reactor pressure vessel model. Strain gages were fixed by means of electrical discharge welding over the cracks regions in both external and internal surfaces. The temperature was monitored in 10 points across the vessel wall. The internal pressure was manually controlled and monitored using a pressure transducer. Two PTS experiments were conducted and this paper presents the strain measurement procedures applied to the reactor pressure vessel model, during the PTS, using strain gages experimental methodology. (authors)

  13. 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

  14. Argonne Bubble Experiment Thermal Model Development II

    Energy Technology Data Exchange (ETDEWEB)

    Buechler, Cynthia Eileen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-07-01

    This report describes the continuation of the work reported in “Argonne Bubble Experiment Thermal Model Development”. The experiment was performed at Argonne National Laboratory (ANL) in 2014. A rastered 35 MeV electron beam deposited power in a solution of uranyl sulfate, generating heat and radiolytic gas bubbles. Irradiations were performed at three beam power levels, 6, 12 and 15 kW. Solution temperatures were measured by thermocouples, and gas bubble behavior was observed. This report will describe the Computational Fluid Dynamics (CFD) model that was developed to calculate the temperatures and gas volume fractions in the solution vessel during the irradiations. The previous report described an initial analysis performed on a geometry that had not been updated to reflect the as-built solution vessel. Here, the as-built geometry is used. Monte-Carlo N-Particle (MCNP) calculations were performed on the updated geometry, and these results were used to define the power deposition profile for the CFD analyses, which were performed using Fluent, Ver. 16.2. CFD analyses were performed for the 12 and 15 kW irradiations, and further improvements to the model were incorporated, including the consideration of power deposition in nearby vessel components, gas mixture composition, and bubble size distribution. The temperature results of the CFD calculations are compared to experimental measurements.

  15. A COMPARISON OF THERMAL EXPLOSIONS IN PBX 9501 AND PBXN-9

    International Nuclear Information System (INIS)

    Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.

    2009-01-01

    We have used a variety of observables to study the response of HMX based energetic materials formulations to thermal stimuli. In this paper, we compare the response of PBX 9501 and PBXN-9 to a temperature of 205 deg. C. Both undergo thermal runaway at this boundary condition with similar preignition behavior. However, the post-ignition burn propagations of the two formulations are very different with the final reaction violence significantly lower for PBXN-9 than for PBX 9501.

  16. Environmental assessment of the thermal neutron activation explosive detection system for concourse use at US airports

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.G.

    1990-08-01

    This document is an environmental assessment of a system designed to detect the presence of explosives in checked airline baggage or cargo. The system is meant to be installed at the concourse or lobby ticketing areas of US commercial airports and uses a sealed radioactive source of californium-252 to irradiate baggage items. The major impact of the use of this system arises from direct exposure of the public to scattered or leakage radiation from the source and to induced radioactivity in baggage items. Under normal operation and the most likely accident scenarios, the environmental impacts that would be created by the proposed licensing action would not be significant. 44 refs., 19 figs., 18 tabs.

  17. Environmental assessment of the thermal neutron activation explosive detection system for concourse use at US airports

    International Nuclear Information System (INIS)

    Jones, C.G.

    1990-08-01

    This document is an environmental assessment of a system designed to detect the presence of explosives in checked airline baggage or cargo. The system is meant to be installed at the concourse or lobby ticketing areas of US commercial airports and uses a sealed radioactive source of californium-252 to irradiate baggage items. The major impact of the use of this system arises from direct exposure of the public to scattered or leakage radiation from the source and to induced radioactivity in baggage items. Under normal operation and the most likely accident scenarios, the environmental impacts that would be created by the proposed licensing action would not be significant. 44 refs., 19 figs., 18 tabs

  18. 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

  19. 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.)

  20. Risk of fire and dust explosions analysis in thermal Power station of ''As Pontes''; Analisis del Riesgo de fuego y Explosion en la Central Termica As Pontes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    Among the numerous difficulties come up in the industrial processes that operate with coal, the handling of combustible solids constitutes a priority objective because of the potential risk of fire and dust explosions that implies. The aim of this project was to determine the coal usage conditions that assure total safety in its manipulation avoiding every risks at the Thermal Power Station. Several variables had to be considered starting with the basis concept of coal, which ranges very different types, compositions and origins and studying the coal handling and operation condition on different areas in the Thermal Power Station. (Author)

  1. 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

  2. Computer program for storage and retrieval of thermal-stability data for explosives

    International Nuclear Information System (INIS)

    Ashcraft, R.W.

    1981-06-01

    A computer program for storage and retrieval of thermal stability data has been written in HP Basic for the HP-9845 system. The data library is stored on a 9885 flexible disk. A program listing and sample outputs are included as appendices

  3. 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.

  4. Micro-differential thermal analysis detection of adsorbed explosive molecules using microfabricated bridges

    DEFF Research Database (Denmark)

    Senesac, Larry R.; Yi, Dechang; Greve, Anders

    2009-01-01

    Although micromechanical sensors enable chemical vapor sensing with unprecedented sensitivity using variations in mass and stress, obtaining chemical selectivity using the micromechanical response still remains as a crucial challenge. Chemoselectivity in vapor detection using immobilized selective...... layers that rely on weak chemical interactions provides only partial selectivity. Here we show that the very low thermal mass of micromechanical sensors can be used to produce unique responses that can be used for achieving chemical selectivity without losing sensitivity or reversibility. We demonstrate...

  5. 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

  6. 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

  7. A Novel Design of Rescue Capsule considering the Pressure Characteristics and Thermal Dynamic Response with Thermomechanical Coupling Action Subjected to Gas Explosion Load

    Directory of Open Access Journals (Sweden)

    Xiaowei Zhai

    2017-01-01

    Full Text Available To ensure the structural safety and reliability of coal mine rescue capsule in disastrous surroundings after gas explosion, in this paper, the thermomechanical coupling effect on a certain structure subjected to gas explosion was analyzed, and then a novel rescue capsule with a combination of radius and square features was designed according to the underground surroundings and relevant regulations on mine rescue devices. Foremost, the coupling mechanism of thermal-fluid-solid interaction between gas explosion shock wave and rescue capsule and the thermal dynamic response of the capsule subjected to explosion load of gas/air mixture was investigated and revealed by employing LS-DYNA. The variation laws and characteristics of stress field, displacement field, and temperature field of the capsule were analyzed based on the simulation results. Results show that the structural safety, tightness, and reliability of the capsule meet the requirements of the national safety regulations. The design method presented in this work provides a new thought for design of coal mine rescue capsule.

  8. The thermal explosion synthesis of AlNi monitored by neutron thermodiffractometry

    International Nuclear Information System (INIS)

    Turrillas, X.; Mas-Guindal, M.J.; Hansen, T.C.; Rodriguez, M.A.

    2010-01-01

    The synthesis of AlNi from thermally activated equimolar powder mixtures of aluminium and nickel was monitored in situ and acquired diffraction patterns every 2 s or less. The analysis of diffraction patterns (λ=1.3112A) permitted establishment of its kinetics, which could be modeled according to an equation expressed as kt=[α/(1-α)] 3/2 . From 1530 to ∼600 deg. C an activation energy of 9 ± 2 kJ mol -1 was estimated. Also, the crystallite size evolution on cooling was established to vary from ∼14 nm at 1530 deg. C to ∼28 nm at 180 deg. C. Finally, the reaction was found to occur through the melting of aluminium and the subsequent dissolving of nickel to form the polycrystalline single-phase product, AlNi.

  9. Thermal-mechanical-chemical responses of polymer-bonded explosives using a mesoscopic reactive model under impact loading.

    Science.gov (United States)

    Wang, XinJie; Wu, YanQing; Huang, FengLei

    2017-01-05

    A mesoscopic framework is developed to quantify the thermal-mechanical-chemical responses of polymer-bonded explosive (PBX) samples under impact loading. A mesoscopic reactive model is developed for the cyclotetramethylenetetranitramine (HMX) crystal, which incorporates nonlinear elasticity, crystal plasticity, and temperature-dependent chemical reaction. The proposed model was implemented in the finite element code ABAQUS by the user subroutine VUMAT. A series of three-dimensional mesoscale models were constructed and calculated under low-strength impact loading scenarios from 100m/s to 600m/s where only the first wave transit is studied. Crystal anisotropy and microstructural heterogeneity are responsible for the nonuniform stress field and fluctuations of the stress wave front. At a critical impact velocity (≥300m/s), a chemical reaction is triggered because the temperature contributed by the volumetric and plastic works is sufficiently high. Physical quantities, including stress, temperature, and extent of reaction, are homogenized from those across the microstructure at the mesoscale to compare with macroscale measurements, which will advance the continuum-level models. The framework presented in this study has important implications in understanding hot spot ignition processes and improving predictive capabilities in energetic materials. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Experiment on thermal insulation and sodium deposition of shield plug

    International Nuclear Information System (INIS)

    Hashiguchi, K.; Honda, M.; Shiratori, H.; Ozaki, O.; Suzuki, M.

    1986-01-01

    A series of experiments on temperature distribution and thermal insulation characteristics was conducted using a reduced scale model of LMFBR shield plug. Observation and measurement of sodium deposition were also conducted on the model after the experiment. The effect of annulus natural convection was clarified for temperature and the thermal insulation characteristics from evaluating the result. Temperature distribution analysis was conducted successfully by combining the general purpose structural analysis program NASTRAN and vertical annulus natural convection analysis program VANAC. Moreover, significant effect was substantiated for the annulus convection barrier to increase the thermal insulation performance, narrow horizontal gap structure to prevent sodium deposition and thermal insulation plates. (author)

  11. 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.

  12. Study on the thermal ignition of gasoline-air mixture in underground oil depots based on experiment and numerical simulation

    Science.gov (United States)

    Ou, Yihong; Du, Yang; Jiang, Xingsheng; Wang, Dong; Liang, Jianjun

    2010-04-01

    The study on the special phenomenon, occurrence process and control mechanism of gasoline-air mixture thermal ignition in underground oil depots is of important academic and applied value for enriching scientific theories of explosion safety, developing protective technology against fire and decreasing the number of fire accidents. In this paper, the research on thermal ignition process of gasoline-air mixture in model underground oil depots tunnel has been carried out by using experiment and numerical simulation methods. The calculation result has been demonstrated by the experiment data. The five stages of thermal ignition course, which are slow oxidation stage, rapid oxidation stage, fire stage, flameout stage and quench stage, have been firstly defined and accurately descried. According to the magnitude order of concentration, the species have been divided into six categories, which lay the foundation for explosion-proof design based on the role of different species. The influence of space scale on thermal ignition in small-scale space has been found, and the mechanism for not easy to fire is that the wall reflection causes the reflux of fluids and changes the distribution of heat and mass, so that the progress of chemical reactions in the whole space are also changed. The novel mathematical model on the basis of unification chemical kinetics and thermodynamics established in this paper provides supplementary means for the analysis of process and mechanism of thermal ignition.

  13. Low gravity fluid-thermal experiments

    International Nuclear Information System (INIS)

    Krotiuk, W.J.; Cuta, J.M.

    1987-06-01

    Pacific Northwest Laboratory (PNL) is the lead laboratory for the thermal-hydraulic research in the US Department of Energy Multimegawatt Space Nuclear Power Program. PNL must provide the tools necessary to analyze proposed space reactor concepts, which include single- and two-phase alkali metal and gas-cooled designs. PNL has divided its activities for this task into three basic areas: computer code development, thermal-hydraulic modeling, and experimentation. The subject of this paper is the low-gravity experimental program currently underway at PNL in support of the MMW Program

  14. Preparation of CL-20 Explosive Nanoparticles and Their Thermal Decomposition Property

    Directory of Open Access Journals (Sweden)

    Dunju Wang

    2016-01-01

    Full Text Available Herein, we develop a novel method for preparing nanohexanitrohexaazaisowurtzitane (nano-CL-20 via ultrasonic spray-assisted electrostatic adsorption (USEA technology. Various experimental conditions which influence safety factors and the crystallization process were studied. Meanwhile, the prepared nano-CL-20 particles were characterized by field emission scanning electron microscopy (FE-SEM, X-ray diffraction (XRD, and Fourier transform infrared (FT-IR spectroscopy. The results show that the obtained nano-CL-20 showed a wide size distribution in the range from 150 to 600 nm with an average of 270 nm. Moreover, their thermal properties were also investigated by differential scanning calorimetry (DSC and thermogravimetry (TG. For nano-CL-20, the exothermal peak is 232.9°C increased by 12°C compared with conventionally manufactured (CM CL-20, and they exhibit fast energy release efficiency as well as more energy release. The simple and continuous approach presented here is expected to be an attractive potential for fabricating other organic nanoparticles.

  15. 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

  16. 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

  17. 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

  18. Comments on thermal runaway experiments in sub-ignition tokamaks

    International Nuclear Information System (INIS)

    Yamazaki, K.

    1982-09-01

    Justification of deuterium-tritium operations is discussed from the physics viewpoint and optimal thermal runaway experiments in high-field, high-density compact tokamaks are suggested within the minimization of the induced radioactivation. (author)

  19. 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.

  20. 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.

  1. 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-...

  2. Electrically Driven Thermal Management: Flight Validation, Experiment Development, Future Technologies

    Science.gov (United States)

    Didion, Jeffrey R.

    2018-01-01

    Electrically Driven Thermal Management is an active research and technology development initiative incorporating ISS technology flight demonstrations (STP-H5), development of Microgravity Science Glovebox (MSG) flight experiment, and laboratory-based investigations of electrically based thermal management techniques. The program targets integrated thermal management for future generations of RF electronics and power electronic devices. This presentation reviews four program elements: i.) results from the Electrohydrodynamic (EHD) Long Term Flight Demonstration launched in February 2017 ii.) development of the Electrically Driven Liquid Film Boiling Experiment iii.) two University based research efforts iv.) development of Oscillating Heat Pipe evaluation at Goddard Space Flight Center.

  3. Thermal hydraulic reactor safety analyses and experiments

    International Nuclear Information System (INIS)

    Holmstroem, H.; Eerikaeinen, L.; Kervinen, T.; Kilpi, K.; Mattila, L.; Miettinen, J.; Yrjoelae, V.

    1989-04-01

    The report introduces the results of the thermal hydraulic reactor safety research performed in the Nuclear Engineering Laboratory of the Technical Research Centre of Finland (VTT) during the years 1972-1987. Also practical applications i.e. analyses for the safety authorities and power companies are presented. The emphasis is on description of the state-of-the-art know how. The report describes VTT's most important computer codes, both those of foreign origin and those developed at VTT, and their assessment work, VTT's own experimental research, as well as international experimental projects and other forms of cooperation VTT has participated in. Appendix 8 contains a comprehensive list of the most important publications and technical reports produced. They present the content and results of the research in detail.(orig.)

  4. 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.

  5. 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

  6. Effects of magnesium-based hydrogen storage materials on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant.

    Science.gov (United States)

    Liu, Leili; Li, Jie; Zhang, Lingyao; Tian, Siyu

    2018-01-15

    MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 were prepared, and their structure and hydrogen storage properties were determined through X-ray photoelectron spectroscopy and thermal analyzer. The effects of MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant were subsequently studied. Results indicated that MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 can decrease the thermal decomposition peak temperature and increase the total released heat of decomposition. These compounds can improve the effect of thermal decomposition of the propellant. The burning rates of the propellant increased using Mg-based hydrogen storage materials as promoter. The burning rates of the propellant also increased using MgH 2 instead of Al in the propellant, but its explosive heat was not enlarged. Nonetheless, the combustion heat of MgH 2 was higher than that of Al. A possible mechanism was thus proposed. Copyright © 2017. Published by Elsevier B.V.

  7. Thermal experiments in the ADS target model

    International Nuclear Information System (INIS)

    Efanov, A.D.; Orlov, Yu.I.; Sorokin, A.P.; Ivanov, E.F.; Bogoslovskaya, G.P.; Li, N.

    2002-01-01

    Experiments on the development of the target heat model project and method of investigation into heat exchange in target were conducted with the aim of analysis of thermomechanical and strength characteristics of device; experimental data on the temperature distribution in coolant and membrane were obtained. Obtained data demonstrate that the temperature heterogeneity of membrane and coolant are connected with the temperature distribution variability near the membrane. Peculiarities of the experiment are noted: maximal temperature of oscillations at high point of the membrane, and power bearing temperature oscillations in the range 0 - 1 Hz [ru

  8. Argonne Bubble Experiment Thermal Model Development

    Energy Technology Data Exchange (ETDEWEB)

    Buechler, Cynthia Eileen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-12-03

    This report will describe the Computational Fluid Dynamics (CFD) model that was developed to calculate the temperatures and gas volume fractions in the solution vessel during the irradiation. It is based on the model used to calculate temperatures and volume fractions in an annular vessel containing an aqueous solution of uranium . The experiment was repeated at several electron beam power levels, but the CFD analysis was performed only for the 12 kW irradiation, because this experiment came the closest to reaching a steady-state condition. The aim of the study is to compare results of the calculation with experimental measurements to determine the validity of the CFD model.

  9. 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

  10. Experience of Milled Peat Burning at Thermal Electric Power Plant

    Directory of Open Access Journals (Sweden)

    G. I. Zhikhar

    2013-01-01

    Full Text Available The paper presents extensive knowledge and practical experience on burning of milled peat in the boilers of thermal electric power plants in Belarus and Russia. The accumulated experience can be used for solution of problems pertaining to substitution of some types of fuel imported to Belarus by milled peat which is extracted at many fuel effective peat enterprises of the Republic.

  11. Specimen environments in thermal neutron scattering experiments

    International Nuclear Information System (INIS)

    Cebula, D.J.

    1980-11-01

    This report is an attempt to collect into one place outline information concerning the techniques used and basic design of sample environment apparatus employed in neutron scattering experiments. Preliminary recommendations for the specimen environment programme of the SNS are presented. The general conclusion reached is that effort should be devoted towards improving reliability and efficiency of operation of specimen environment apparatus and developing systems which are robust and easy to use, rather than achieving performance at the limits of technology. (author)

  12. Experiments on thermal conductivity in buffer materials for geologic repository

    International Nuclear Information System (INIS)

    Kanno, T.; Yano, T.; Wakamatsu, H.; Matsushima, E.

    1989-01-01

    Engineered barriers for geologic disposal for HLW are planned to consist of canister, overpack and buffer elements. One of important physical characteristics of buffer materials is determining temperature profiles within the near field in a repository. Buffer materials require high thermal conductivity to disperse radiogenic heat away to the host rock. As the buffer materials, compacted blocks of the mixture of sodium bentonite and sand have been the most promising candidate in some countries, e.g. Sweden, Switzerland and Japan. The authors have been carrying out a series of thermal dispersion experiments to evaluate thermal conductivity of bentonite/quartz sand blocks. In this study, the following two factors considered to affect thermal properties of the near field were examined: effective thermal conductivities of buffer materials, and heat transfer characteristics of the gap between overpack and buffer materials

  13. 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.

  14. Preliminary experiments on wastes degradation by thermal plasma

    International Nuclear Information System (INIS)

    Cota S, G.; Pacheco S, J.; Segovia R, A.; Pena E, R.; Merlo S, L.

    1996-01-01

    This work presents the fundamental aspects involved in the installation and start up of an experimental equipment for the hazardous wastes degradation using the thermal plasma technology. It is mentioned about the form in which the thermal plasma is generated and the characteristics that its make to be an appropriate technology for the hazardous wastes degradation. Just as the installed structures for to realize the experiments and results of the first studies on degradation, using nylon as problem sample. (Author)

  15. Designing solar thermal experiments based on simulation

    International Nuclear Information System (INIS)

    Huleihil, Mahmoud; Mazor, Gedalya

    2013-01-01

    In this study three different models to describe the temperature distribution inside a cylindrical solid body subjected to high solar irradiation were examined, beginning with the simpler approach, which is the single dimension lump system (time), progressing through the two-dimensional distributed system approach (time and vertical direction), and ending with the three-dimensional distributed system approach with azimuthally symmetry (time, vertical direction, and radial direction). The three models were introduced and solved analytically and numerically. The importance of the models and their solution was addressed. The simulations based on them might be considered as a powerful tool in designing experiments, as they make it possible to estimate the different effects of the parameters involved in these models

  16. Thermal responses in underground experiments in a dome salt formation

    International Nuclear Information System (INIS)

    Llewellyn, G.H.

    1977-01-01

    To provide design information for a radwaste repository in dome salt, in-situ experiments with nonradioactive heat sources are planned. Three such experiments using electrical heat sources are scheduled to be carried out in a salt dome. The purpose of these experiments is to acquire rock mechanics data to ascertain the structural deformation due to the thermal load imposed, to study brine migration and corrosion, and to provide thermal data. A data acquisition system is provided with these experiments to monitor temperatues, heat fluxes, stresses, and ground displacement. A thermal analysis was made on models of each of these experiments. The objective of the analysis is to verify the capability of making accurate transient temperature predictions by the use of computer modeling techniques. Another purpose is to measure in-situ thermal conductivity and compare the results with measurements taken from core samples. The HEATING5 computer program was used to predict transient temperatures around the experiments for periods up to 2 years using two-dimensional and three-dimensional heat transfer models. The results of analysis are presented with the associated boundary conditions used in the individual models

  17. Gas explosions and thermal runaways during external heating abuse of commercial lithium-ion graphite-LiCoO2 cells at different levels of ageing

    Science.gov (United States)

    Larsson, Fredrik; Bertilsson, Simon; Furlani, Maurizio; Albinsson, Ingvar; Mellander, Bengt-Erik

    2018-01-01

    Commercial 6.8 Ah lithium-ion cells with different ageing/status have been abused by external heating in an oven. Prior to the abuse test, selected cells were aged either by C/2 cycling up to 300 cycles or stored at 60 °C. Gas emissions were measured by FTIR and three separate vents were identified, two well before the thermal runaway while the third occurred simultaneously with the thermal runaway releasing heavy smoke and gas. Emissions of toxic carbon monoxide (CO), hydrogen fluoride (HF) and phosphorous oxyfluoride (POF3) were detected in the third vent, regardless if there was a fire or not. All abused cells went into thermal runaway and emitted smoke and gas, the working cells also released flames as well as sparks. The dead cells were however less reactive but still underwent thermal runaway. For about half of the working cells, for all levels of cycle ageing, ignition of the accumulated battery released gases occurred about 15 s after the thermal runaway resulting in a gas explosion. The thermal runaway temperature, about 190 °C, varied somewhat for the different cell ageing/status where a weak local minimum was found for cells cycled between 100 and 200 times.

  18. High-throughput trace analysis of explosives in water by laser diode thermal desorption/atmospheric pressure chemical ionization-tandem mass spectrometry.

    Science.gov (United States)

    Badjagbo, Koffi; Sauvé, Sébastien

    2012-07-03

    Harmful explosives can accumulate in natural waters in the long term during their testing, usage, storage, and dumping and can pose a health risk to humans and the environment. For the first time, attachment of small anions to neutral molecules in laser diode thermal desorption/atmospheric pressure chemical ionization was systematically investigated for the direct determination of trace nitroaromatics, nitrate esters, and nitramine explosives in water. Using ammonium chloride as an additive improved the instrument response for all the explosives tested and promoted the formation of several characteristic adduct ions. The method performs well achieving good linearity over at least 2 orders of magnitude, with coefficients of determination greater than 0.995. The resulting limits of detection are in the range of 0.009-0.092 μg/L. River water samples were successfully analyzed by the proposed method with accuracy in the range of 96-98% and a response time of 15 s, without any further pretreatment or chromatographic separation.

  19. 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

  20. Recent results from TMX-U thermal barrier experiments

    International Nuclear Information System (INIS)

    Molvik, A.W.; Allen, S.; Barter, J.

    1984-01-01

    The Tandem Mirror Experiment-Upgrade (TMX-U) device was designed to study plasma confinement in a tandem mirror with thermal barriers. Previously the author reported improved axial confinement with high end-plug potentials, consistent with thermal barrier operation. Now, the existence of thermal barriers in TMX-U confirmed by measuring the axial potential profile. Specifically, measured the change in energy of a 5-keV deuterium neutral beam that is injected nearly parallel to the axis and is ionized between the barrier and the central cell. The authors found that the barrier potential is lower than the central cell potential, as required for a thermal barrier. The peak potential is at least 2.4 keV, as determined from the minimum energy of end loss ions. In addition, radial transport is reduced by the use of floating and electrodes that map to concentric cylinders in the central cell. Sloshing ions continue to be microstable

  1. THERMAL EVALUATION OF ALTERNATE SHIPPING CASK FOR GTRI EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Donna Post Guillen

    2014-06-01

    The Global Threat Reduction Initiative (GTRI) has many experiments yet to be irradiated in support of the High Performance Research Reactor fuels development program. Most of the experiments will be irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL), then later shipped to the Hot Fuel Examination Facility (HFEF) located at the Materials and Fuels Complex for post irradiation examination. To date, the General Electric (GE)-2000 cask has been used to transport GTRI experiments between these facilities. However, the availability of the GE-2000 cask to support future GTRI experiments is at risk. In addition, the internal cavity of the GE-2000 cask is too short to accommodate shipping the larger GTRI experiments. Therefore, an alternate shipping capability is being pursued. The Battelle Energy Alliance, LLC, Research Reactor (BRR) cask has been determined to be the best alternative to the GE-2000 cask. An evaluation of the thermal performance of the BRR cask is necessary before proceeding with fabrication of the newly designed cask hardware and the development of handling, shipping, and transport procedures. This paper presents the results of the thermal evaluation of the BRR cask loaded with a representative set of fueled and non-fueled experiments. When analyzed with identical payloads, experiment temperatures were found to be lower with the BRR cask than with the GE-2000 cask. From a thermal standpoint, the BRR cask was found to be a suitable alternate to the GE-2000 cask.

  2. Pressurized-thermal-shock experiments with thick vessels

    International Nuclear Information System (INIS)

    Bryan, R.H.; Nanstad, R.K.; Merkle, J.G.; Robinson, G.C.; Whitman, G.D.

    1986-01-01

    Information is provided on the series of pressurized-thermal-shock experiments at the Oak Ridge National Laboratory, motivated by a concern for the behavior of flaws in reactor pressure vessels having welds or shells exhibiting low upper-shelf Charpy impact energies, approx. 68J or less

  3. TMX-U [Tandem Mirror Experiment-Upgrade] tandem-mirror thermal-barrier experiments

    International Nuclear Information System (INIS)

    Simonen, T.C.; Allen, S.L.; Baldwin, D.E.

    1986-01-01

    Thermal-barrier experiments have been carried out in the Tandem Mirror Experiment-Upgrade (TMX-U). Measurements of nonambipolar and ambipolar radial transport show that these transport processes, as well as end losses, can be controlled at modest densities and durations. Central-cell heating methods using ion-cyclotron heating (ICH) and neutral-beam injection have been demonstrated. Potential mesurements with recently developed methods indicate that deep thermal barriers can be established

  4. A test of the comet hypothesis of the Tunguska Meteor Fall - Nature of the meteor 'thermal' explosion paradox

    Science.gov (United States)

    Liu, V. C.

    1978-01-01

    The hypothesis that a comet was responsible for the Tunguska Meteor Fall is rejected because the hypothesis does not seem to account for the intense terminal spherical shock. A porous meteoroid model is proposed, and an analysis indicates that an entity of this type might produce an aerodynamic heat flux large enough to account for the terminal meteor explosion. It is suggested that the presence of olivine and of highly irregular macrostructure in meteors might indicate the presence of some porosity. For a highly porous meteoroid, it is postulated that during entry into the atmosphere the aerodynamic heat transfer at its external or pore walls would become so intensified as to cause either complete ablation with popping or a solid-liquid-vapor phase transition accompanied by an explosion.

  5. 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

  6. Thermal control surfaces on the MSFC LDEF experiments

    International Nuclear Information System (INIS)

    Wilkes, D.R.; Whitaker, A.F.; Zwiener, J.M.; Linton, R.C.; Shular, D.; Peters, P.N.; Gregory, J.C.

    1992-01-01

    There were five Marshall Space Flight Center (MSFC) experiments on the LDEF. Each of those experiments carried thermal control surfaces either as test samples or as operational surfaces. These materials experienced varying degrees of mechanical and optical damage. Some materials were virtually unchanged by the extended exposure while others suffered extensive degradation. The synergistic effects due to the constituents of the space environment are evident in the diversity of these material changes. The sample complement for the MSFC experiments is described along with results of the continuing analyses efforts

  7. Heat experiment design to estimate temperature dependent thermal properties

    International Nuclear Information System (INIS)

    Romanovski, M

    2008-01-01

    Experimental conditions are studied to optimize transient experiments for estimating temperature dependent thermal conductivity and volumetric heat capacity. A mathematical model of a specimen is the one-dimensional heat equation with boundary conditions of the second kind. Thermal properties are assumed to vary nonlinearly with temperature. Experimental conditions refer to the thermal loading scheme, sampling times and sensor location. A numerical model of experimental configurations is studied to elicit the optimal conditions. The numerical solution of the design problem is formulated on a regularization scheme with a stabilizer minimization without a regularization parameter. An explicit design criterion is used to reveal the optimal sensor location, heating duration and flux magnitude. Results obtained indicate that even the strongly nonlinear experimental design problem admits the aggregation of its solution and has a strictly defined optimal measurement scheme. Additional region of temperature measurements with allowable identification error is revealed.

  8. 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

  9. Methodical Specifics of Thermal Experiments with Thin Carbon Reinforced Plates

    Directory of Open Access Journals (Sweden)

    O. V. Denisov

    2015-01-01

    Full Text Available Polymer composite materials (CM are widely used in creation of large space constructions, especially reflectors of space antennas. Composite materials should provide high level of specific stiffness and strength for space structures. Thermal conductivity in reinforcement plane is a significant factor in case of irregular heating space antennas. Nowadays, data on CM reinforcement plane thermal conductivity are limited and existing methods of its defining are imperfect. Basically, traditional methods allow us to define thermal conductivity in perpendicular direction towards the reinforcement plane on the samples of round or rectangular plate. In addition, the thickness of standard samples is larger than space antenna thickness. Consequently, new methods are required. Method of contact heating, which was developed by BMSTU specialists with long hollow carbon beam, could be a perspective way. This article is devoted to the experimental method of contact heating on the thin carbon plates.Thermal tests were supposed to provide a non-stationary temperature field with a gradient being co-directional with the plane reinforcement in the material sample. Experiments were conducted in vacuum chamber to prevent unstructured convection. Experimental thermo-grams processing were calculated by 1-d thermal model for a thin plate. Influence of uncertainty of experimental parameters, such as (radiation emission coefficients of sample surface, glue, temperature sensors and uncertainty of sensors placement on the result of defined thermal conductivity has been estimated. New data on the thermal conductivity in reinforcement plane were obtained within 295 - 375 K temperature range, which can be used to design and develop reflectors of precision space antennas. In the future it is expedient to conduct tests of thin-wall plates from carbon fiber-reinforced plastic in wide temperature range, especially in the low-range temperatures.

  10. Activation experiment for concrete blocks using thermal neutrons

    Science.gov (United States)

    Okuno, Koichi; Tanaka, Seiichiro

    2017-09-01

    Activation experiments for ordinary concrete, colemanite-peridotite concrete, B4C-loaded concrete, and limestone concrete are carried out using thermal neutrons. The results reveal that the effective dose for gamma rays from activated nuclides of colemanite-peridotite concrete is lower than that for the other types of concrete. Therefore, colemanite-peridotite concrete is useful for reducing radiation exposure for workers.

  11. New high-nitrogen materials based on nitroguanyl-tetrazines: explosive properties, thermal decomposition and combustion studies

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, David E.; Tappan, Bryce C.; Hiskey, Michael A.; Son, Steve F.; Harry, Herbert; Montoya, Dennis; Hagelberg, Stephanie [Dynamic Experimentation Division, DX-2 Materials Dynamics Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2005-12-01

    This paper describes the explosive sensitivity and performance properties of two novel high-nitrogen materials, 3,6-bis-nitroguanyl-1,2,4,5-tetrazine (1, (NQ{sub 2}Tz)) and its corresponding bis-triaminoguanidinium salt (2, (TAG){sub 2}(NQ){sub 2}Tz). These materials exhibit very low pressure dependence in burning rate. Flash pyrolysis/FTIR spectroscopy was performed, and insight into this interesting burning behavior was obtained. Our studies indicate that 1 and 2 exhibit highly promising energetic materials properties. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  12. Adjunctive hyperbaric oxygen therapy in severe burns: Experience in Taiwan Formosa Water Park dust explosion disaster.

    Science.gov (United States)

    Chiang, I-Han; Chen, Shyi-Gen; Huang, Kun-Lun; Chou, Yu-Ching; Dai, Niann-Tzyy; Peng, Chung-Kan

    2017-06-01

    Despite major advances in therapeutic strategies for the management of patients with severe burns, significant morbidity and mortality is observed. Hyperbaric oxygen therapy (HBOT) increases the supply of oxygen to burn areas. The aim of this study was to determine whether HBOT is effective in the treatment of major thermal burns. On June 27, 2015 in New Taipei, Taiwan, a mass casualty disaster occurred as fire erupted over a large crowd, injuring 499 people. Fifty-three victims (20 women and 33 men) were admitted to Tri-Service General Hospital. Thirty-eight patients underwent adjunctive HBOT (HBOT group), and 15 patients received routine burn therapy (control group). Serum procalcitonin (PCT) level, a sepsis biomarker, was measured until it reached normal levels (burn care combined with adjunctive HBOT improves sepsis control compared with standard treatment without HBOT. Prospective studies are required to define the role of HBOT in extensive burns. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  13. Effect of Ti and C particle sizes on reaction behavior of thermal explosion reaction of Cu−Ti−C system under Ar and air atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Yunhong; Zhao, Qian; Li, Xiujuan; Zhang, Zhihui, E-mail: zhzh@jlu.edu.cn; Ren, Luquan

    2016-09-15

    The thermal explosion (TE) reaction behavior of Cu−Ti−C systems with different Ti and C particle sizes was investigated under air and Ar atmospheres. It was found that increasing the Ti and C particle sizes leads to higher ignition temperatures under both atmospheres and that the maximum combustion temperature decreases with increasing C particle size. The TE reaction is much easier to activate (i.e., it has a lower ignition temperature) in air because of the heat released from Ti oxidation and nitridation and Cu oxidation reactions on the Cu−Ti−C compact surface. TiC ceramic particles are successfully prepared in the bulk Cu−Ti−C compacts under both air and Ar atmospheres through a dissolution-diffusion-precipitation mechanism. Differential thermal and thermodynamic analyses show that the TE reaction ignition process in air is mainly controlled by the Ti particle size. - Highlights: • Variation of Ti and C particle sizes affects thermal reaction (TE) behaviors. • Ignition temperature under air is much lower than that under Ar atmosphere. • Heat of oxidation and nitridation reactions reduces ignition temperature under air.

  14. Is the Experience of Thermal Pain Genetics Dependent?

    Directory of Open Access Journals (Sweden)

    Emilia Horjales-Araujo

    2015-01-01

    Full Text Available It is suggested that genetic variations explain a significant portion of the variability in pain perception; therefore, increased understanding of pain-related genetic influences may identify new targets for therapies and treatments. The relative contribution of the different genes to the variance in clinical and experimental pain responses remains unknown. It is suggested that the genetic contributions to pain perception vary across pain modalities. For example, it has been suggested that more than 60% of the variance in cold pressor responses can be explained by genetic factors; in comparison, only 26% of the variance in heat pain responses is explained by these variations. Thus, the selection of pain model might markedly influence the magnitude of the association between the pain phenotype and genetic variability. Thermal pain sensation is complex with multiple molecular and cellular mechanisms operating alone and in combination within the peripheral and central nervous system. It is thus highly probable that the thermal pain experience is affected by genetic variants in one or more of the pathways involved in the thermal pain signaling. This review aims to present and discuss some of the genetic variations that have previously been associated with different experimental thermal pain models.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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.

  4. Thermal-hydraulic Experiments for Advanced Physical Model Development

    International Nuclear Information System (INIS)

    Song, Chulhwa

    2012-04-01

    The improvement of prediction models is needed to enhance the safety analysis capability through experimental database of local phenomena. To improve the two-phase interfacial area transport model, the various experiments were carried out with local two-phase interfacial structure test facilities. 2 Χ 2 and 6 Χ 6 rod bundle test facilities were used for the experiment on the droplet behavior. The experiments on the droplet behavior inside a heated rod bundle geometry. The experiments used GIRLS and JICO and CFD analysis were carried out to comprehend the local condensation of steam jet, turbulent jet induced by condensation and the thermal mixing in a pool. In order to develop a model for key phenomena of newly adapted safety system, experiments for boiling inside a pool and condensation in horizontal channel have been performed. An experimental database of the CHF (Critical Heat Flux) and PDO (Post-dryout) was constructed. The mechanism of the heat transfer enhancement by surface modifications in nano-fluid was investigated in boiling mode and rapid quenching mode. The special measurement techniques were developed. They are Double-sensor optical void probe, Optic Rod, PIV technique and UBIM system

  5. 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.

  6. Numerical analysis of two experiments related to thermal fatigue

    Energy Technology Data Exchange (ETDEWEB)

    Bieder, Ulrich; Errante, Paolo [DEN-STMF, Commissariat a l' Energie Atomique et aux Energies Alternatives, Universite Paris-Saclay, Gif-sur-Yvette (France)

    2017-06-15

    Jets in cross flow are of fundamental industrial importance and play an important role in validating turbulence models. Two jet configurations related to thermal fatigue phenomena are investigated: • T-junction of circular tubes where a heated jet discharges into a cold main flow and • Rectangular jet marked by a scalar discharging into a main flow in a rectangular channel. The T-junction configuration is a classical test case for thermal fatigue phenomena. The Vattenfall T-junction experiment was already subject of an OECD/NEA benchmark. A LES modelling and calculation strategy is developed and validated on this data. The rectangular-jet configuration is important for basic physical understanding and modelling and has been analyzed experimentally at CEA. The experimental work was focused on turbulent mixing between a slightly heated rectangular jet which is injected perpendicularly into the cold main flow of a rectangular channel. These experiments are analyzed for the first time with LES. The overall results show a good agreement between the experimental data and the CFD calculation. Mean values of velocity and temperature are well captured by both RANS calculation and LES. The range of critical frequencies and their amplitudes, however, are only captured by LES.

  7. Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems

    International Nuclear Information System (INIS)

    Song, C. H.; Baek, W. P.; Chung, M. K.

    2007-06-01

    The objectives of the project are to study thermal hydraulic characteristics of advanced nuclear reactor system for evaluating key thermal-hydraulic phenomena relevant to new safety concepts. To meet the research goal, several thermal hydraulic experiments were performed and related thermal hydraulic models were developed with the experimental data which were produced through the thermal hydraulic experiments. The Followings are main research topics: - Multi-dimensional Phenomena in a Reactor Vessel Downcomer - Condensation-induced Thermal Mixing in a Pool - Development of Thermal-Hydraulic Models for Two-Phase Flow - Construction of T-H Data Base

  8. Thermal-hydraulic Experiments for Advanced Physical Model Development

    International Nuclear Information System (INIS)

    Song, Chul Hwa; Baek, W. P.; Yoon, B. J.

    2010-04-01

    The improvement of prediction models is needed to enhance the safety analysis capability through the fine measurements of local phenomena. To improve the two-phase interfacial area transport model, the various experiments were carried out used SUBO and DOBO. 2x2 and 6x6 rod bundle test facilities were used for the experiment on the droplet behavior. The experiments on the droplet behavior inside a heated rod bundle were focused on the break-up of droplets induced by a spacer grid in a rod bundle geometry. The experiments used GIRLS and JICO and CFD analysis were carried out to comprehend the local condensation of steam jet, turbulent jet induced by condensation and the thermal mixing in a pool. An experimental database of the CHF (Critical Heat Flux) and PDO (Post-dryout) had been constructed. The mechanism of the heat transfer enhancement by surface modifications in nano-fluid was investigated in boiling mode and rapid quenching mode. The special measurement techniques were developed. They are Double -sensor optical void probe, Optic Rod, PIV technique and UBIM system

  9. 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

  10. Thermal experiments in the model of ADS target

    International Nuclear Information System (INIS)

    Alexander, Efanov; Yuri, Orlov; Alexander, Sorokin; Eugeni, Ivanov; Galina, Bogoslovskaia; Ning, Li

    2002-01-01

    The paper presents thermal experiments performed in the SSC RF IPPE on the ADS window target model. Brief description of the model, specific features of structure, measurement system and some methodological approaches are presented. Eutectic lead-bismuth alloy is modeled here by eutectic sodium-potassium alloy. The following characteristics of the target model were measured directly and estimated by processing: coolant flow rate, model power, absolute temperature of the coolant with a distance from the membrane of the target, absolute temperature of the membrane surface, mean square value and pulsating component of coolant temperature, as well as membrane temperature. Measurements have shown a great pulsations of temperature existing at the membrane surface that must be taken into account in analysis of strength of real target system. Experimental temperature fields (present work) and velocity fields measured earlier make up a complete database for verification of 2D and 3D thermohydraulic codes. (author)

  11. COMMIX analysis of four constant flow thermal upramp experiments performed in a thermal hydraulic model of an advanced LMR

    International Nuclear Information System (INIS)

    Yarlagadda, B.S.

    1989-04-01

    The three-dimensional thermal hydraulics computer code COMMIX-1AR was used to analyze four constant flow thermal upramp experiments performed in the thermal hydraulic model of an advanced LMR. An objective of these analyses was the validation of COMMIX-1AR for buoyancy affected flows. The COMMIX calculated temperature histories of some thermocouples in the model were compared with the corresponding measured data. The conclusions of this work are presented. 3 refs., 5 figs

  12. 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.

  13. 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

  14. 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.

  15. A review of human thermal comfort experiments in controlled and semi-controlled environments

    NARCIS (Netherlands)

    Craenendonck, Van Stijn; Lauriks, Leen; Vuye, Cedric; Kampen, Jarl

    2018-01-01

    There are three main methods to improve thermal comfort in existing buildings: modeling, experiments and measurements. Regarding experiments, no standardized procedure exists. This article provides an answer to the question: “What is the most common practice for human thermal comfort experiments in

  16. 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.

  17. 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.

  18. Results of measurements of thermal interaction between molten metal and water

    International Nuclear Information System (INIS)

    Zyszkowski, W.

    1975-10-01

    The report describes results of an experimental investigation into thermal interaction of molten metals with water. The experiments were performed in two stages: the aim of the first stage was to study the general character of thermal interaction between molten metal and water and to measure the Leidenfrost temperature of the inverse Leidenfrost phenomenon. The second stage was directed to the experimental study of the triggering mechanism of thermal explosion. The experimental material gathered in this study includes: 1) transient temperature measurements in the hot material and in water, 2) measurements of pressure and reactive force combined with thermal explosion, 3) high-speed films of thermal interaction, 4) investigation results of thermal explosion debris (microscopic, mechanical, metallographical and chemical). The most significant observation is, that small jets from the main particle mass occuring 1 to 10 msec before, precede thermal explosion. (orig.) [de

  19. 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

  20. 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.

  1. Experimental simulation of microinteractions in large scale explosions

    Energy Technology Data Exchange (ETDEWEB)

    Chen, X.; Luo, R.; Yuen, W.W.; Theofanous, T.G. [California Univ., Santa Barbara, CA (United States). Center for Risk Studies and Safety

    1998-01-01

    This paper presents data and analysis of recent experiments conducted in the SIGMA-2000 facility to simulate microinteractions in large scale explosions. Specifically, the fragmentation behavior of a high temperature molten steel drop under high pressure (beyond critical) conditions are investigated. The current data demonstrate, for the first time, the effect of high pressure in suppressing the thermal effect of fragmentation under supercritical conditions. The results support the microinteractions idea, and the ESPROSE.m prediction of fragmentation rate. (author)

  2. High speed imaging, lightning mapping arrays and thermal imaging: a synergy for the monitoring of electrical discharges at the onset of volcanic explosions

    Science.gov (United States)

    Gaudin, Damien; Cimarelli, Corrado; Behnke, Sonja; Cigala, Valeria; Edens, Harald; McNutt, Stefen; Smith, Cassandra; Thomas, Ronald; Van Eaton, Alexa

    2017-04-01

    Volcanic lightning is being increasingly studied, due to its great potential for the detection and monitoring of ash plumes. Indeed, it is observed in a large number of ash-rich volcanic eruptions and it produces electromagnetic waves that can be detected remotely in all weather conditions. Electrical discharges in volcanic plume can also significantly change the structural, chemical and reactivity properties of the erupted material. Although electrical discharges are detected in various regions of the plume, those happening at the onset of an explosion are of particular relevance for the early warning and the study of volcanic jet dynamics. In order to better constrain the electrical activity of young volcanic plumes, we deployed at Sakurajima (Japan) in 2015 a multiparametric set-up including: i) a lightning mapping array (LMA) of 10 VHF antennas recording the electromagnetic waves produced by lightning at a sample rate of 25 Msps; ii) a visible-light high speed camera (5000 frames per second, 0.5 m pixel size, 300 m field of view) shooting short movies (approx. duration 1 s) at different stages of the plume evolution, showing the location of discharges in relation to the plume; and iii) a thermal camera (25 fps, 1.5 m pixel size, 800 m field of view) continuously recording the plume and allowing the estimation of its main source parameters (volume, rise velocity, mass eruption rate). The complementarity of these three setups is demonstrated by comparing and aggregating the data at various stages of the plume development. In the earliest stages, the high speed camera spots discrete small discharges, that appear on the LMA data as peaks superimposed to the continuous radio frequency (CRF) signal. At later stages, flashes happen less frequently and increase in length. The correspondence between high speed camera and LMA data allows to define a direct correlation between the length of the flash and the intensity of the electromagnetic signal. Such correlation is

  3. Steam explosions of single drops of pure and alloyed molten aluminum

    International Nuclear Information System (INIS)

    Nelson, L.S.

    1995-01-01

    Studies of steam explosion phenomena have been performed related to the hypothetical meltdown of the core and other components of aluminum alloy-fueled production reactors. Our objectives were to characterise the triggers, if any, required to initiate these explosions and to determine the energetics and chemical processes associated with these events. Three basic studies have been carried out with 1-10 g single drops of molten aluminum or aluminum-based alloys: untriggered experiments in which drops of melt were released into water; triggered experiments in which thermal-type steam explosions occurred; and one triggered experiment in which an ignition-type steam explosion occurred. In untriggered experiments, spontaneous steam explosions never occurred during the free fall through water of single drops of pure Al or of the alloys studied here. Moreover, spontaneous explosions never occurred upon or during contact of the globules with several underwater surfaces. When Li was present in the alloy, H 2 was generated as a stream of bubbles as the globules fell through the water, and also as they froze on the bottom surface of the chamber. The triggered experiments were performed with pure Al and the 6061 alloy. Bare bridgewire discharges and those focused with cylindrical reflectors produced a small first bubble that collapsed and was followed by a larger second bubble. When the bridgewire was discharged at one focus of an ellipsoidal reflector, a melt drop at the other focus triggered only very mildly in spite of a 30-fold increase in peak pressure above that of the bridgewire discharge without the reflector. Experiments were also performed with globules of high purity Al in which the melt release temperature was progressively increased. Moderate thermal-type explosions were produced over the temperature range 1273-1673 K. At about 1773 K, however, one experiment produced a brilliant flash of light and bubble growth about an order of magnitude faster than normal; it

  4. 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.

  5. 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.

  6. Solar photovoltaic/thermal residential experiment. Phase I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Darkazalli, G.

    1980-07-01

    Month-by-month energy transfer data between an occupied residence and its energy supply systems are presented. The data were obtained during the first phase of photovoltaic/thermal residential research conducted at the University of Texas at Arlington/Solar Energy Research Facility. This research was part of the US Department of Energy Photovoltaic/Thermal Project managed by the M.I.T. Lincoln Laboratory. Energy transfer data are divided into different categories depending on how the energy is consumed. Energy transfers between some system components are also categorized. These components include a flat-plate thermal collector array, a flat-plate photovoltaic array, a dc-to-ac inverter, thermal storage tanks, and a series heat pump. System operations included directing surplus electrical energy (generated by the photovoltaic array) into the local utility grid. The heat pump used off-peak utility power to chill water during the cooling season.

  7. Predicting Large-scale Effects During Cookoff of Plastic-Bonded Explosives (PBX 9501 PBX 9502 and LX-14)

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, Michael L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kaneshige, Michael J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Erikson, William W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-10-01

    In this study, we have made reasonable cookoff predictions of large-scale explosive systems by using pressure-dependent kinetics determined from small-scale experiments. Scale-up is determined by properly accounting for pressure generated from gaseous decomposition products and the volume that these reactive gases occupy, e.g. trapped within the explosive, the system, or vented. The pressure effect on the decomposition rates has been determined for different explosives by using both vented and sealed experiments at low densities. Low-density explosives are usually permeable to decomposition gases and can be used in both vented and sealed configurations to determine pressure-dependent reaction rates. In contrast, explosives that are near the theoretical maximum density (TMD) are not as permeable to decomposition gases, and pressure-dependent kinetics are difficult to determine. Ignition in explosives at high densities can be predicted by using pressure-dependent rates determined from the low-density experiments as long as gas volume changes associated with bulk thermal expansion are also considered. In the current work, cookoff of the plastic-bonded explosives PBX 9501 and PBX 9502 is reviewed and new experimental work on LX-14 is presented. Reactive gases are formed inside these heated explosives causing large internal pressures. The pressure is released differently for each of these explosives. For PBX 9501, permeability is increased and internal pressure is relieved as the nitroplasticizer melts and decomposes. Internal pressure in PBX 9502 is relieved as the material is damaged by cracks and spalling. For LX-14, internal pressure is not relieved until the explosive thermally ignites. The current paper is an extension of work presented at the 26th ICDERS symposium [1].

  8. 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.

  9. 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).

  10. 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)

  11. 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.

  12. Dynamic mechanical and molecular weight measurements on polymer bonded explosives from thermally accelerated aging tests. III. Kraton block copolymer binder and plasticizers

    International Nuclear Information System (INIS)

    Caley, L.E.; Hoffman, D.M.

    1981-01-01

    The dynamic mechanical properties and molecular weight distribution of two experimental polymer bonded explosives, X-0287 and X-0298, maintained at 23, 60, and 74 0 C for 3 years were examined. X-0287 is 97% 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane explosive, 1.8% Kraton G-1650, and 1.2% B 2 was 170. X-0298 is 97.4% explosive, 1.4% Kraton G-1650, and 1.2% Cenco Hi-vac oil. The relaxation associated with the Kraton rubber block glass transition is observed in both X-0287 and X-0298. In the unaged X-0298 it occurs at -59 0 C and in the aged explosive at 50 0 C. This is caused by migration of the oil plasticizer out of the explosive. In X-0287 the Kraton rubber block T/sub g/ is weak and broad due to the presence of the wax plasticizer. X-0287 has a second broad relaxation associated with the melting of the wax from 10 to 65 0 C. The molecular weight of the Kraton binder decreased with increasing accelerated aging temperature. The oil plasticizer had no stabilizing effect, but below its melting point the wax reduced Kraton chain scission considerably. The simple random chain scission model predicted a 20.5 year use-life for X-0298, but X-0287 was stabilized against degradation below the wax melting point

  13. Thermal imaging experiments on ANACONDA ion beam generator

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Weihua; Yatsui, Kiyoshi [Nagaoka University of Technology (Japan). Lab. of Beam Technology; Olson, C J; Davis, H A [Los Alamos National Laboratory, Los Alamos, NM (United States)

    1997-12-31

    The thermal imaging technique was used in two experimental measurements. First, the ion intensity distribution on the anode surface was observed from different angles by using a multi-pinhole camera. Second, the plume from a target intercepting the beam was visualized by observing the distribution of temperature increase on a thin plate hit by the plume. (author). 6 figs., 4 refs.

  14. Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems

    International Nuclear Information System (INIS)

    Song, C. H.; Chung, M. K.; Park, C. K. and others

    2005-04-01

    The objectives of the project are to study thermal hydraulic characteristics of reactor primary system for the verification of the reactor safety and to evaluate new safety concepts of new safety design features. To meet the research goal, several thermal hydraulic experiments were performed and related thermal hydraulic models were developed with the experimental data which were produced through the thermal hydraulic experiments. Followings are main research topics; - Multi-dimensional Phenomena in a Reactor Vessel Downcomer - Condensation Load and Thermal Mixing in the IRWST - Development of Thermal-Hydraulic Models for Two-Phase Flow - Development of Measurement Techniques for Two-Phase Flow - Supercritical Reactor T/H Characteristics Analysis From the above experimental and analytical studies, new safety design features of the advanced power reactors were verified and lots of the safety issues were also resolved

  15. Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Song, C. H.; Chung, M. K.; Park, C. K. and others

    2005-04-15

    The objectives of the project are to study thermal hydraulic characteristics of reactor primary system for the verification of the reactor safety and to evaluate new safety concepts of new safety design features. To meet the research goal, several thermal hydraulic experiments were performed and related thermal hydraulic models were developed with the experimental data which were produced through the thermal hydraulic experiments. Followings are main research topics; - Multi-dimensional Phenomena in a Reactor Vessel Downcomer - Condensation Load and Thermal Mixing in the IRWST - Development of Thermal-Hydraulic Models for Two-Phase Flow - Development of Measurement Techniques for Two-Phase Flow - Supercritical Reactor T/H Characteristics Analysis From the above experimental and analytical studies, new safety design features of the advanced power reactors were verified and lots of the safety issues were also resolved.

  16. The Importance of a Thermal Manikin as Source and Obstacle in Full-Scale Experiments

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    The thermal manikin is normally introduced at indoor environmental measurements to obtain detailed information on thermal comfort and air quality around a person. This paper deals with the opposite situation where manikins are introduced as sources and obstacles in order to obtain reasonable...... boundary conditions in experiments with the indoor environment. In other words, how will people influence the surroundings instead of how will the surroundings influence people? The use of thermal manikins in an experiment will of course take both situations into account, however, in some experiments...

  17. The Lattice and Thermal Radiation Conductivity of Thermal Barrier Coatings: Models and Experiments

    Science.gov (United States)

    Zhu, Dongming; Spuckler, Charles M.

    2010-01-01

    The lattice and radiation conductivity of ZrO2-Y2O3 thermal barrier coatings was evaluated using a laser heat flux approach. A diffusion model has been established to correlate the coating apparent thermal conductivity to the lattice and radiation conductivity. The radiation conductivity component can be expressed as a function of temperature, coating material scattering, and absorption properties. High temperature scattering and absorption of the coating systems can be also derived based on the testing results using the modeling approach. A comparison has been made for the gray and nongray coating models in the plasma-sprayed thermal barrier coatings. The model prediction is found to have a good agreement with experimental observations.

  18. Experience with thermal recycle of plutonium and uranium

    International Nuclear Information System (INIS)

    Beer, O.; Schlosser, G.; Spielvogel, F.

    1985-01-01

    The Federal Republic of Germany (FRG) decided to close the fuel cycle by erecting the reprocessing plant WA350 at Wackersdorf. As long as the plutonium supply from reprocessing plants exceeds the plutonium demand of fast breeder reactors, recycling of plutonium in LWR's is a convenient solution by which a significant advanced uranium utilization is achieved. The demonstration of plutonium recycling performed to date in the FRG in BWR's and PWR's shows that thermal plutonium recycling on an industrial scale is feasible and that the usual levels of reliability and safety can be achieved in reactor operation. The recycling of reprocessed uranium is presently demonstrated in the FRG, too. As regards fuel cycle economy thermal recycling allows savings in natural uranium and separative work. Already under present cost conditions the fuel cycle costs for mixed oxide or enriched reprocessed uranium fuel assemblies are equal or even lower than for usual uranium fuel assemblies

  19. Equipping simulators with an advanced thermal hydraulics model EDF's experience

    International Nuclear Information System (INIS)

    Soldermann, R.; Poizat, F.; Sekri, A.; Faydide, B.; Dumas, J.M.

    1997-01-01

    The development of an accelerated version of the advanced CATHARe-1 thermal hydraulics code designed for EDF training simulators (CATHARE-SIMU) was successfully completed as early as 1991. Its successful integration as the principal model of the SIPA Post-Accident Simulator meant that its use could be extended to full-scale simulators as part of the renovation of the stock of existing simulators. In order to further extend the field of application to accidents occurring in shutdown states requiring action and to catch up with developments in respect of the CATHARE code, EDF initiated the SCAR Project designed to adapt CATHARE-2 to simulator requirements (acceleration, parallelization of the computation and extension of the simulation range). In other respects, the installation of SIPA on workstations means that the authors can envisage the application of this remarkable training facility to the understanding of thermal hydraulics accident phenomena

  20. Utility experience using THERMAC for plant thermal performance analysis

    International Nuclear Information System (INIS)

    Jain, P.K.; Doran, K.J.

    1993-01-01

    THERMAC is a state-of-the-art software package designed to assist those responsible for monitoring and evaluating the thermal performance of fossil and nuclear power plants. It is an integrated program, available on PCs and selected workstations, that combines strong analytical capabilities with a graphical user interface and object-oriented database. The software accurately analyses all of the components of a power plant from first principles. The graphical user interface is employed to build plant specific models; it can also be used to create custom screen displays. THERMAC is able to read plant measurements and statistically account for any missing or erroneous plant data; it does not require any additional plant instrumentation. THERMAC can be used to archive historical data, generate customized trending plots and periodic performance reports. open-quotes What-if close-quote studies can be conducted to predict the impact of corrective actions on thermal performance

  1. What is the best clothing to prevent heat and cold stress? Experiences with thermal manikin.

    Science.gov (United States)

    Magyar, Z; Tamas, R

    2013-02-01

    The present study summarizes the current knowledge of the heat and cold stress which might significantly affect military activities and might also occur among travellers who are not well adapted to weather variations during their journey. The selection of the best clothing is a very important factor in preserving thermal comfort. Our experiences with thermal manikin are also represented in this paper.

  2. Processing of thermal scattering data with NJOY experience and comments

    International Nuclear Information System (INIS)

    Mattes, M.

    1989-01-01

    The THERMR module of NJOY-89 generates pointwise integrated cross sections and double differential neutron scattering cross sections in the thermal energy range where the binding of the scatterer in a material or the motion of atoms in a gas is important. The results are added to an existing PENDF tape using special MT numbers in the range 221 to 250. The cross sections can then be group-averaged with the GROUPR module or plotted and reformated in subsequent modules

  3. Thermal-shock experiments with flawed clad cylinders

    International Nuclear Information System (INIS)

    Cheverton, R.D.; Bryson, J.W.; Alexander, D.J.

    1989-01-01

    The life expectancy of LWR pressure vessels is influenced by a reduction in fracture toughness that is the result of radiation damage. As the fracture toughness decreases, the probability of propagation of preexisting flaws (sharp, crack-like defects) in the wall of the vessel increases. The probability of propagation is also influenced by the type of loading condition and the type of flaws that might exist. A loading condition of particular concern is referred to as pressurized thermal shock (PTS), and a flaw of particular concern for PTS loading conditions is a shallow surface flaw. A sudden cooling (thermal shock) of the inner surface of the vessel results in relatively high tensile stresses and relatively low fracture toughness at the inner surface. In addition, the attenuation of the fast-neutron fluence also results in relatively low fracture toughness at the inner surface. Under some circumstances, this combination of high stress and low toughness at the inner surface makes it possible for very shallow surface flaws to propagate. The PTS issue has been under investigation for quite some time, but thus far possible beneficial effects, other than thermal resistance, of the cladding on the inner surface of the vessel have not been included in the analysis of flaw behavior. This document discusses this effect of cladding on surface flaws and crack propagation

  4. 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.

  5. 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.)

  6. 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)

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. Experience base for Radioactive Waste Thermal Processing Systems: A preliminary survey

    International Nuclear Information System (INIS)

    Mayberry, J.; Geimer, R.; Gillins, R.; Steverson, E.M.; Dalton, D.; Anderson, G.L.

    1992-04-01

    In the process of considering thermal technologies for potential treatment of the Idaho National Engineering Laboratory mixed transuranic contaminated wastes, a preliminary survey of the experience base available from Radioactive Waste Thermal Processing Systems is reported. A list of known commercial radioactive waste facilities in the United States and some international thermal treatment facilities are provided. Survey focus is upon the US Department of Energy thermal treatment facilities. A brief facility description and a preliminary summary of facility status, and problems experienced is provided for a selected subset of the DOE facilities

  12. 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.

  13. 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

  14. 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)

  15. Promotion of solar thermal energy - guide and comparison of experience

    Energy Technology Data Exchange (ETDEWEB)

    Ballot, E [ALTER Alsace (France)

    2004-01-01

    One of the objectives of the guide is to analyse the methods of the various partners of the project (Germany, Cyprus, Town of Barcelona and France) and to make a list with the most important ones, which could eventually be reproduced and adapted in other regions. Also, try to find out the problems that the various partners encounter (lack of information, technical and financial tools...), look for the best ways for developing the solar thermal energy and try to find out some answers from the stake holders of this domain and from our partners. (author)

  16. Shuttle Orbiter Active Thermal Control Subsystem design and flight experience

    Science.gov (United States)

    Bond, Timothy A.; Metcalf, Jordan L.; Asuncion, Carmelo

    1991-01-01

    The paper examines the design of the Space Shuttle Orbiter Active Thermal Control Subsystem (ATCS) constructed for providing the vehicle and payload cooling during all phases of a mission and during ground turnaround operations. The operation of the Shuttle ATCS and some of the problems encountered during the first 39 flights of the Shuttle program are described, with special attention given to the major problems encountered with the degradation of the Freon flow rate on the Orbiter Columbia, the Flash Evaporator Subsystem mission anomalies which occurred on STS-26 and STS-34, and problems encountered with the Ammonia Boiler Subsystem. The causes and the resolutions of these problems are discussed.

  17. Thermal experiments with LMFBR subassembly models in sodium flow

    International Nuclear Information System (INIS)

    Moeller, R.; Tschoeke, H.

    1982-01-01

    Within the framework of the Fast Breeder Project research work has been undertaken at the Karlsruhe Nuclear Research Center on the thermal and fluid dynamics of nominal and distorted core subassemblies. In 19-rod bundle models (P/D=1.30, W/R=1.38) three-dimensional temperature distributions were measured in the cladding tubes exposed to sodium flow. Results of measurements of the azimuthal temperature profiles of rotated rods in the duct wall zone are indicated for different operating conditions 80 2 , evenly distributed load and oblique load; different axial positions of the spacer grids; and different positions of one bowed rod

  18. 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)

  19. 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)

  20. Adsorption thermal energy storage for cogeneration in industrial batch processes: Experiment, dynamic modeling and system analysis

    International Nuclear Information System (INIS)

    Schreiber, Heike; Graf, Stefan; Lanzerath, Franz; Bardow, André

    2015-01-01

    Adsorption thermal energy storage is investigated for heat supply with cogeneration in industrial batch processes. The feasibility of adsorption thermal energy storage is demonstrated with a lab-scale prototype. Based on these experiments, a dynamic model is developed and successfully calibrated to measurement data. Thereby, a reliable description of the dynamic behavior of the adsorption thermal energy storage unit is achieved. The model is used to study and benchmark the performance of adsorption thermal energy storage combined with cogeneration for batch process energy supply. As benchmark, we consider both a peak boiler and latent thermal energy storage based on a phase change material. Beer brewing is considered as an example of an industrial batch process. The study shows that adsorption thermal energy storage has the potential to increase energy efficiency significantly; primary energy consumption can be reduced by up to 25%. However, successful integration of adsorption thermal storage requires appropriate integration of low grade heat: Preferentially, low grade heat is available at times of discharging and in demand when charging the storage unit. Thus, adsorption thermal energy storage is most beneficial if applied to a batch process with heat demands on several temperature levels. - Highlights: • A highly efficient energy supply for industrial batch processes is presented. • Adsorption thermal energy storage (TES) is analyzed in experiment and simulation. • Adsorption TES can outperform both peak boilers and latent TES. • Performance of adsorption TES strongly depends on low grade heat temperature.

  1. 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

  2. Mineralogical control on thermal damage and the presence of a thermal Kaiser effect during temperature-cycling experiments

    Science.gov (United States)

    Browning, J.; Daoud, A.; Meredith, P. G.; Mitchell, T. M.

    2017-12-01

    Volcanic and geothermal systems are in part controlled by the mechanical and thermal stresses acting on them and so it is important to understand the response of volcanic rocks to thermo-mechanical loading. One such response is the well-known `Kaiser stress-memory' effect observed under cyclic mechanical loading. By contrast, the presence of an analogous `Kaiser temperature-memory effect' during cyclic thermal loading has received little attention. We have therefore explored the possibility of a Kaiser temperature-memory effect using three igneous rocks of different composition, grain size and origin; Slaufrudalur Granophyre (SGP), Nea Kameni Andesite (NKA) and Seljadalur Basalt (SB). We present results from a series of thermal stressing experiments in which acoustic emissions (AE) were recorded contemporaneously with changing temperature. Samples of each rock were subjected to both a single heating and cooling cycle to a maximum temperature of 900 °C and multiple heating/cooling cycles to peak temperatures of 350°C, 500°C, 700°C and 900 °C (all at a constant rate of 1°C/min on heating and a natural cooling rate of memory effect in SGP, but not in either NKA and SB. We further find that the vast majority of thermal crack damage is generated upon cooling in the finer grained materials (NKA and SB), but that substantial thermal crack damage is generated during heating in the coarser grained SGP. The total amount of crack damage generated due to heating or cooling is dependent on the mineral composition and, most importantly, the grain size and arrangement, as well as the maximum temperature to which the rock is exposed. Knowledge of thermal stress history and the presence of a Kaiser temperature-memory effect is potentially important in understanding magma chamber dynamics, where the cyclic nature of mechanical and thermal inflation and deflation can lead to sequential accumulation of damage, potentially leading to critical rupture.

  3. Soudage par explosion thermique sous charge de cermets poreux à base de TiC-Ni sur substrat en acier-comportement tribologique Welding of porous TiC–Ni based cermets on substrate steel by thermal explosion under load-tribological behaviour

    Directory of Open Access Journals (Sweden)

    Lemboub Samia

    2013-11-01

    Full Text Available Dans ce travail, nous nous intéressons à l'élaboration de cermets à base de TiC-Ni par dispersion de particules de carbures, oxydes ou borures dans une matrice de nickel, grâce à la technique de l'explosion thermique sous une charge de 20 MPa. La combustion de mélanges actifs (Ti-C-Ni-An où An = Al2O3, MgO, SiC, TiB2, WC, basée sur la réaction de synthèse de TiC (ΔHf298K = −184 kJ/mole, génère des cermets complexes. Un court maintien sous charge du cermet à 1373 K, après l'explosion thermique, permet son soudage sur un substrat en acier XC55. Les cermets obtenus dans ces conditions demeurent poreux et conservent une porosité de l'ordre de 25–35 %. La densité relative du cermet, sa dureté et son comportement tribologique, dépendront de la nature de l'addition dans les mélanges de départ. Porous TiC-Ni based cermets were obtained by dispersion of carbides, oxides or borides particles in a nickel matrix thanks to the thermal explosion technique realized under a load of 20 MPa. The combustion of active mixtures (Ti-C-Ni-An where An = Al2O3, MgO, SiC, TiB2 or WC based on the titanium carbide reaction synthesis (ΔHf = −184 kJ/mol, generates porous complex cermets. After the thermal explosion, a short maintenance under load at 1373 K of the combustion product, allows at the same time the cermets welding on a carbon steel substrate. The obtained cermets under these conditions preserve a porosity of about 25–35%. The relative density, hardness and tribological behaviour of the complex cermets depend on the additions nature (An in the starting mixtures.

  4. Thermal and Field Enhanced Photoemission Comparison of Theory to Experiment

    CERN Document Server

    Lynn-Jensen, Kevin

    2004-01-01

    Photocathodes are a critical component of high-gain FEL’s and the analysis of their emission is complex. Relating their performance under laboratory conditions to conditions of an rf photoinjector is difficult. Useful models must account for cathode surface conditions and material properties, as well as drive laser parameters. We have developed a time-dependent model accounting for the effects of laser heating and thermal propagation on photoemission. It accounts for surface conditions (coating, field enhancement, reflectivity), laser parameters (duration, intensity, wavelength), and material characteristics (reflectivity, laser penetration depth, scattering rates) to predict current distribution and quantum efficiency. The applicatIon will focus on photoemission from metals and, in particular, dispenser photocathodes: the later introduces complications such as coverage non-uniformity and field enhancement. The performance of experimentally characterized photocathodes will be extrapolated to 0.1 - 1 nC bunch...

  5. 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...

  6. 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).

  7. 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

  8. 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.)

  9. Thermal-hydraulic experiments for the PCHE type steam generator

    International Nuclear Information System (INIS)

    Shin, C. W.; No, H. C.

    2015-01-01

    Printed circuit heat exchanger (PCHE) manufactured by HEATRIC is a compact type of the mini-channel heat exchanger. The PCHE is manufactured by diffusion bonding of the chemically-etched plates, and has high heat transfer rate due to a large surface. Therefore, the size of heat exchanger can be reduced by 1/5 - 1/6 and PCHE can be operated under high pressure, high temperature and multi-phase flow. Under such merits, it is used as heat exchanger with various purposes of gas cycle and water cycle. Recently, it is newly suggested as an application of a steam generator. IRIS of MIT and FASES of KAIST conceptually adopted PCHE as a steam generator. When using boiling condition of micro-channel, flow instability is one of the critical issues. Instability may cause unstable mass flow rate, sudden temperature change and system control failure. However instability tests of micro channels using water are very limited because the previous studies were focused on a single tube or other fluid instead of water. In KAIST, we construct the test facility to study the thermal hydraulics and fluid dynamics of the heat exchanger, especially occurrence of instability. By inducing the pressure drop of inlet water, amplitude of oscillation declined by 90%. Finally, the throttling effect was experimentally confirmed that PCHE could be utilized as a steam generator

  10. Thermal-hydraulic experiments and analyses on cold moderator

    International Nuclear Information System (INIS)

    Aso, Tomokazu; Kaminaga, Masanori; Terada, Atsushi; Hino, Ryutaro

    2001-01-01

    A cold moderator using supercritical hydrogen is one of the key components in a MW-scale spallation target system, which directly affects the neutronic performance both in intensity and resolution. Since a hydrogen temperature rise in the moderator vessel affects the neutronic performance, it is necessary to suppress the local temperature rise within 3 K. In order to develop the conceptual design of the moderator structure in progress, the flow patterns were measured using a PIV (Particle Image Velocimeter) system under water flow conditions using a flat model that simulated a moderator vessel. From these results, the flow patterns (such as recirculation flows, stagnant flows etc.) were clarified. The hydraulic analytical results obtained using the STAR-CD code agreed well with experimental results. Thermal-hydraulic analyses in the moderator vessel were carried out using the STAR-CD code. Based on these results, we clarified the possibility of suppressing the local temperature rise to within 3 K under 2 MW operating conditions. In order to achieve the cost decreasing of the hydrogen loop, it is necessary to operate it reducing the hydrogen flow rate and the whole hydrogen mass. Then improved moderator concept using blowholes and a twisted tape was proposed, and we have tried to examine the effect of the blowing flow from the inlet pipe. From the experimental and analytical results, the blowing flow could be feasible for the suppression of the stagnant region. (author)

  11. Thermal safety characterization on PETN, PBX-9407, LX-10-2, LX-17-1 and detonator in the LLNL's P-ODTX system

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, P. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Strout, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, J. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kahl, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ellsworth, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Healy, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-21

    Incidents caused by fire and other thermal events can heat energetic materials that may lead to thermal explosion and result in structural damage and casualty. Thus, it is important to understand the response of energetic materials to thermal insults. The One-Dimensional-Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory (LLNL) has been used for decades to characterize thermal safety of energetic materials. In this study, an integration of a pressure monitoring element has been added into the ODTX system (P-ODTX) to perform thermal explosion (cook-off) experiments (thermal runaway) on PETN powder, PBX-9407, LX-10-2, LX-17-1, and detonator samples (cup tests). The P-ODTX testing generates useful data (thermal explosion temperature, thermal explosion time, and gas pressures) to assist with the thermal safety assessment of relevant energetic materials and components. This report summarizes the results of P-ODTX experiments that were performed from May 2015 to July 2017. Recent upgrades to the data acquisition system allows for rapid pressure monitoring in microsecond intervals during thermal explosion. These pressure data are also included in the report.

  12. Pretest thermal analysis of the Tuff Water Migration/In-Situ Heater Experiment

    International Nuclear Information System (INIS)

    Bulmer, B.M.

    1980-02-01

    This report describes the pretest thermal analysis for the Tuff Water Migration/In-Situ Heater Experiment to be conducted in welded tuff in G-tunnel, Nevada Test Site. The parametric thermal modeling considers variable boiling temperature, tuff thermal conductivity, tuff emissivity, and heater operating power. For nominal tuff properties, some near field boiling is predicted for realistic operating power. However, the extent of boiling will be strongly determined by the ambient (100% water saturated) rock thermal conductivity. In addition, the thermal response of the heater and of the tuff within the dry-out zone (i.e., bounded by boiling isotherm) is dependent on the temperature variation of rock conductivity as well as the extent of induced boiling

  13. Additive model for thermal comfort generated by matrix experiment using orthogonal array

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Reuy-Lung [Department of Occupational Safety and Health, China Medical University, 91 Huseh-shin Road, Taichung 404 (China); Lin, Tzu-Ping [Department of Leisure Planning, National Formosa University, 64 Wen-hua Road, Huwei, Yunlin 632 (China); Liang, Han-Hsi [Department of Architecture, National United University, No. 1, Lien Da, Kung-Ching Li, Miaoli 360 (China); Yang, Kuan-Hsiug; Yeh, Tsung-Chyn [Department of Mechanical and Electro-Mechanical Engineering, National Sun Yet-Sen University, No. 91, Lien-hai Road, Kaohsiung (China)

    2009-08-15

    In addition to ensuring the thermal comfort of occupants, monitoring and controlling indoor thermal environments can reduce the energy consumed by air conditioning systems. This study develops an additive model for predicting thermal comfort with rapid and simple arithmetic calculations. The advantage of the additive model is its comprehensibility to administrators of air conditioning systems, who are unfamiliar with the PMV-PPD model but want to adjust an indoor environment to save energy without generating complaints of discomfort from occupants. In order to generate the additive model, a laboratory chamber experiment based on matrix experiment using orthogonal array, was performed. By applying the analysis of variance on observed thermal sensation votes and percentage of dissatisfaction, the factor effects of environmental variables that account for the additive model were determined. Additionally, the applicability of the PMV-PPD model in hot and humid climates is discussed in this study, based on experimental results. (author)

  14. Thermal and orbital analysis of Earth monitoring Sun-synchronous space experiments

    Science.gov (United States)

    Killough, Brian D.

    1990-01-01

    The fundamentals of an Earth monitoring Sun-synchronous orbit are presented. A Sun-synchronous Orbit Analysis Program (SOAP) was developed to calculate orbital parameters for an entire year. The output from this program provides the required input data for the TRASYS thermal radiation computer code, which in turn computes the infrared, solar and Earth albedo heat fluxes incident on a space experiment. Direct incident heat fluxes can be used as input to a generalized thermal analyzer program to size radiators and predict instrument operating temperatures. The SOAP computer code and its application to the thermal analysis methodology presented, should prove useful to the thermal engineer during the design phases of Earth monitoring Sun-synchronous space experiments.

  15. Experiment study on thermal mixing performance of HTR-PM reactor outlet

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yangping, E-mail: zhouyp@mail.tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, the Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Tsinghua University, Beijing 100084 (China); Hao, Pengfei [School of Aerospace, Tsinghua University, Beijing 100084 (China); Li, Fu; Shi, Lei [Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, the Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Tsinghua University, Beijing 100084 (China); He, Feng [School of Aerospace, Tsinghua University, Beijing 100084 (China); Dong, Yujie; Zhang, Zuoyi [Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, the Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Tsinghua University, Beijing 100084 (China)

    2016-09-15

    A model experiment is proposed to investigate the thermal mixing performance of HTR-PM reactor outlet. The design of the test facility is introduced, which is set at a scale of 1:2.5 comparing with the design of thermal mixing structure at HTR-PM reactor outlet. The test facility using air as its flow media includes inlet pipe system, electric heaters, main mixing structure, hot gas duct, exhaust pipe system and I&C system. Experiments are conducted on the test facility and the values of thermal-fluid parameters are collected and analyzed, which include the temperature, pressure and velocity of the flow as well as the temperature of the tube wall. The analysis results show the mixing efficiency of the test facility is higher than that required by the steam generator of HTR-PM, which indicates that the thermal mixing structure of HTR-PM fulfills its design requirement.

  16. Steam explosions in sodium cooled breeder reactors

    International Nuclear Information System (INIS)

    Lundell, B.

    1982-01-01

    Steam explosion is considered a physical process which transport heat from molten fuel to liquid coolant so fast that the coolant starts boiling in an explosion-like manner. The arising pressure waves transform part of the thermal energy to mechanical energy. This can stress the reactor tank and threaten its hightness. The course of the explosion has not been theoretical explained. Experimental results indicate that the probability of steam explosions in a breeder reactor is small. The efficiency of the transformation of the heat of fusion into mechanical energy in substantially lower than the theoretical maximum value. The mechanical stress from the steam explosion on the reactor tank does not seem to jeopardize its tightness. (G.B.)

  17. Thermal hydraulic phenomena in corium pools: the BALI experiment

    International Nuclear Information System (INIS)

    Bonnet, J.M.

    1999-01-01

    In the framework of severe accident studies, the BALI experiment has been designed to create a data base about heat transfer distribution at corium pool boundaries for in-vessel or ex-vessel configurations. The mechanism investigated is natural convection at high internal Rayleigh number (10 15 to 10 17 ) in cavities with volumetric heating. After a description of the facility and a synthesis of results obtained for in-vessel configurations, the purpose of this paper is to present or extend local or average heat transfer correlations in the prototypic range of dimensionless parameters. (author)

  18. Plasma diagnostic techniques in thermal-barrier tandem-mirror fusion experiments

    International Nuclear Information System (INIS)

    Silver, E.H.; Clauser, J.F.; Carter, M.R.; Failor, B.H.; Foote, J.H.; Hornady, R.S.; James, R.A.; Lasnier, C.J.; Perkins, D.E.

    1986-01-01

    We review two classes of plasma diagnostic techniques used in thermal-barrier tandem-mirror fusion experiments. The emphasis of the first class is to study mirror-trapped electrons at the thermal-barrier location. The focus of the second class is to measure the spatial and temporal behavior of the plasma space potential at various axial locations. The design and operation of the instruments in these two categories are discussed and data that are representative of their performance is presented

  19. 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

  20. Thermal striping heat transfer measurements in sodium AKB experiments

    International Nuclear Information System (INIS)

    Sheriff, N.; Sephton, K.P.; Gleave, C.

    1988-01-01

    Temperature fluctuations are produced in the sodium flow of fast reactors where hot and cold flow streams mix. A sodium experiment mounted on the Interatom facility AKB has been used to measure the heat transfer conditions in a flow stream with typical temperature fluctuations. The measurements were made at locations near to the leading edge of a plate, where in practice the most severe conditions are expected. With tests carried out over a wide range of flows good correlations of the heat transfer data with flow have been obtained. A simple theoretical model is proposed to explain the magnitude of the measured heat transfer coefficients, and the use of reasonable assumptions in the model produce good agreement with the experimental measurements

  1. Plutonium-enriched thermal fuel production experience in Belgium

    International Nuclear Information System (INIS)

    LeBlanc, J.M.

    1983-01-01

    Taking into account the strategic aspects of nuclear energy such as availability and sufficiency of resources and independence of energy supply, most countries planning to use plutonium look mainly to its use in fast reactors. However, by recycling the recovered uranium and plutonium in light water reactors, the saving of the uranium that would otherwise be required could already be higher than 35%. Therefore, until fast reactors are introduced, for macro- or microeconomic reasons, the plutonium recycle option seems to be quite valuable for countries having the plutonium technology. In Belgium, Belgonucleaire has been developing the plutonium technology for more than 20 yr and has operated a mixed oxide fuel fabrication plant since 1973. The past ten years of plant operation have provided for many improvements and relevant new documented experiences establishing a basis for new modifications that will be beneficial to the intrinsic quality, overall safety, and economy of the fuel

  2. 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.

  3. 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.

  4. Coating and Characterization of Mock and Explosive Materials

    Directory of Open Access Journals (Sweden)

    Emily M. Hunt

    2012-01-01

    Full Text Available This project develops a method of manufacturing plastic-bonded explosives by using use precision control of agglomeration and coating of energetic powders. The energetic material coating process entails suspending either wet or dry energetic powders in a stream of inert gas and contacting the energetic powder with atomized droplets of a lacquer composed of binder and organic solvent. By using a high-velocity air stream to pneumatically convey the energetic powders and droplets of lacquer, the energetic powders are efficiently wetted while agglomerate drying begins almost immediately. The result is an energetic powder uniformly coated with binder, that is, a PBX, with a high bulk density suitable for pressing. Experiments have been conducted using mock explosive materials to examine coating effectiveness and density. Energetic materials are now being coated and will be tested both mechanically and thermally. This allows for a comprehensive comparison of the morphology and reactivity of the newly coated materials to previously manufactured materials.

  5. Steam explosions in light water reactors

    International Nuclear Information System (INIS)

    1981-01-01

    The report deals with a postulated accident caused by molten fuel falling into the lower plenum of the containment of a reactor. The analysis which is presented in the report shows that the thermal energy released in the resulting steam explosion is not enough to destroy the pressure vessel or the containment. The report was prepared for the Swedish Governmental Committee on steam explosion in light water reactors. It includes statements issued by internationally well-known specialists. (G.B.)

  6. Thermal anchoring of wires in large scale superconducting coil test experiment

    International Nuclear Information System (INIS)

    Patel, Dipak; Sharma, A.N.; Prasad, Upendra; Khristi, Yohan; Varmora, Pankaj; Doshi, Kalpesh; Pradhan, S.

    2013-01-01

    Highlights: • We addressed how thermal anchoring in large scale coil test is different compare to small cryogenic apparatus? • We did precise estimation of thermal anchoring length at 77 K and 4.2 K heat sink in large scale superconducting coil test experiment. • We addressed, the quality of anchoring without covering entire wires using Kapton/Teflon tape. • We obtained excellent results in temperature measurement without using GE Varnish by doubling estimated anchoring length. -- Abstract: Effective and precise thermal anchoring of wires in cryogenic experiment is mandatory to measure temperature in milikelvin accuracy and to avoid unnecessary cooling power due to additional heat conduction from room temperature (RT) to operating temperature (OT) through potential, field, displacement and stress measurement instrumentation wires. Instrumentation wires used in large scale superconducting coil test experiments are different compare to cryogenic apparatus in terms of unique construction and overall diameter/area due to errorless measurement in large time-varying magnetic field compare to small cryogenic apparatus, often shielded wires are used. Hence, along with other variables, anchoring techniques and required thermal anchoring length are entirely different in this experiment compare to cryogenic apparatus. In present paper, estimation of thermal anchoring length of five different types of instrumentation wires used in coils test campaign at Institute for Plasma Research (IPR), India has been discussed and some temperature measurement results of coils test campaign have been presented

  7. Thermal-hydraulic experiments and analyses for cold moderators

    International Nuclear Information System (INIS)

    Aso, Tomokazu; Kaminaga, Masanori; Hino, Ryutaro

    2003-01-01

    Cold moderators using liquid hydrogen are one of the key components in a MW-scale target system working as a spallation neutron source. The cold moderators directly affect the neutronic performance both in intensity and resolution. Cold moderator vessels are designed to be flat and cylindrical type vessels, which are required to realize and uniform temperature distribution in the vessel to obtain better neutronic performance. Velocity distributions in the moderator vessels, affecting the temperature distributions, were measured by using moderator models under water flowing conditions. In the experiments, jet-induced flows such as recirculation flows and stagnant regions were observed. For the flat type moderator vessel, the analytical results of velocity distributions using a standard k-ε turbulence model agreed well with experimental results obtained with a PIV system. However, for the cylindrical type moderator vessel, especially predicted heat transfer coefficients on a bottom of the vessel were much lower than the experimental results, which gave conservative analytical result of temperature. (author)

  8. MCNP benchmark analyses of critical experiments for the Space Nuclear Thermal Propulsion program

    International Nuclear Information System (INIS)

    Selcow, E.C.; Cerbone, R.J.; Ludewig, H.; Mughabghab, S.F.; Schmidt, E.; Todosow, M.; Parma, E.J.; Ball, R.M.; Hoovler, G.S.

    1993-01-01

    Benchmark analyses have been performed of Particle Bed Reactor (PBR) critical experiments (CX) using the MCNP radiation transport code. The experiments have been conducted at the Sandia National Laboratory reactor facility in support of the Space Nuclear Thermal Propulsion (SNTP) program. The test reactor is a nineteen element water moderated and reflected thermal system. A series of integral experiments have been carried out to test the capabilities of the radiation transport codes to predict the performance of PBR systems. MCNP was selected as the preferred radiation analysis tool for the benchmark experiments. Comparison between experimental and calculational results indicate close agreement. This paper describes the analyses of benchmark experiments designed to quantify the accuracy of the MCNP radiation transport code for predicting the performance characteristics of PBR reactors

  9. MCNP benchmark analyses of critical experiments for the Space Nuclear Thermal Propulsion program

    Science.gov (United States)

    Selcow, Elizabeth C.; Cerbone, Ralph J.; Ludewig, Hans; Mughabghab, Said F.; Schmidt, Eldon; Todosow, Michael; Parma, Edward J.; Ball, Russell M.; Hoovler, Gary S.

    1993-01-01

    Benchmark analyses have been performed of Particle Bed Reactor (PBR) critical experiments (CX) using the MCNP radiation transport code. The experiments have been conducted at the Sandia National Laboratory reactor facility in support of the Space Nuclear Thermal Propulsion (SNTP) program. The test reactor is a nineteen element water moderated and reflected thermal system. A series of integral experiments have been carried out to test the capabilities of the radiation transport codes to predict the performance of PBR systems. MCNP was selected as the preferred radiation analysis tool for the benchmark experiments. Comparison between experimental and calculational results indicate close agreement. This paper describes the analyses of benchmark experiments designed to quantify the accuracy of the MCNP radiation transport code for predicting the performance characteristics of PBR reactors.

  10. UK experience of safety requirements for thermal reactor stations

    International Nuclear Information System (INIS)

    Matthews, R.R.; Dale, G.C.; Tweedy, J.N.

    1977-01-01

    The paper summarises the development of safety requirements since the first of the Generating Boards' Magnox reactors commenced operation in 1962 and includes A.G.R. safety together with the preparation of S.G.H.W.R. design safety criteria. It outlines the basic principles originally adopted and shows how safety assessment is a continuing process throughout the life of a reactor. Some description is given of the continuous effort over the years to obtain increased safety margins for existing and new reactors, taking into account the construction and operating experience, experimental information, and more sophisticated computer-aided design techniques which have become available. The main safeguards against risks arising from the Generating Boards' reactors are the achievement of high standards of design, construction and operation, in conjunction with comprehensive fault analyses to ensure that adequate protective equipment is provided. The most important analyses refer to faults which can lead to excessive fuel element temperatures arising from an increase in power or a reduction in cooling capacity. They include the possibility of unintended control rod withdrawal at power or at start-up, coolant flow failure, pressure circuit failure, loss of boiler feed water, and failure of electric power. The paper reviews the protective equipment, and the policy for reactor safety assessments which include application of maximum credible accident philosophy and later the limited use of reliability and probability methods. Some of the Generating Boards' reactors are now more than half way through their planned working lives and during this time safety protective equipment has occasionally been brought into operation, often for spurious reasons. The general performance, of safety equipment is reviewed particularly for incidents such as main turbo-alternator trip, circulator failure, fuel element failures and other similar events, and some problems which have given rise to

  11. The changing landscape of thermal experience and warmth in older people’s dwellings

    International Nuclear Information System (INIS)

    Tweed, Christopher; Humes, Nicholas; Zapata-Lancaster, Gabriela

    2015-01-01

    The UK's carbon dioxide reduction policy initiatives often treat environmental conditions in buildings as averaged values of air temperature that flatten spatial variations. This discounts the influence of varying thermal conditions on how people use buildings and the impact this may have on energy consumption. This paper explores the intersection between older people's thermal experience, spatial and temporal variations in thermal conditions in a dwelling and the influence this has on occupants' use of space. The paper reports on qualitative studies in homes with both conventional and newly installed low carbon heating systems. The results suggest that older people are sensitive to and adept at exploiting variations in the dynamic ‘landscape’ of warmth to achieve desired thermal preferences and that they modify their dwellings to improve the quality of the thermal environment. There is also some evidence of a ‘spatial rebound’ effect after energy upgrades, when occupants inhabit rooms they previously could not afford to heat. The nature of qualitative research precludes robust recommendations for policy. However, one important avenue to explore further appears to be that householders may be more strongly motivated by interventions offering improvements across a range of aspects rather than on energy savings alone. -- Highlights: •Thermal variations across space affect the use of space within a dwelling. •Older people show interest in and understanding of thermal behavior of dwellings. •Older people pursue the thermal conditions they desire. •Older people take actions to modify the quality of the thermal environment in their house. •Changes made to the house may not be solely motivated by thermal comfort concerns

  12. 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.

  13. Experiments and numerical simulations of fluctuating thermal stratification in a branch pipe

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Akira; Murase, Michio; Sasaki, Toru [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan); Takenaka, Nobuyuki; Hamatani, Daisuke [Kobe Univ. (Japan)

    2002-09-01

    Many pipes branch off from the main pipe in plants. When the main flow in the main pipe is hotter than a branch pipe that branches off downward, the hot water penetrates into the branch pipe with the cavity flow that is induced by the main flow and causes thermal stratification. If the interface of the stratification fluctuates in an occluded branch pipe, thermal fatigue may occur in pipe wall. Some experiments and numerical simulations were conducted to elucidate the mechanism of this fluctuating thermal stratification. The vortex structures were observed in the experiments of straight or bent branch pipes. When the main flow was heated and the thermal stratification interface was at the elbow, a ''burst'' phenomenon occurred in the interface in connection with large heat fluctuation. The effects of pipe shape on the length of penetration were investigated in order to modify simulation conditions. The vortex structures and the fluctuating thermal stratification at elbow in the numerical simulation showed good agreement with experiments. (author)

  14. 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)

  15. Modelling of thermal shock experiments of carbon based materials in JUDITH

    International Nuclear Information System (INIS)

    Ogorodnikova, O.V.; Pestchanyi, S.; Koza, Y.; Linke, J.

    2005-01-01

    The interaction of hot plasma with material in fusion devices can result in material erosion and irreversible damage. Carbon based materials are proposed for ITER divertor armour. To simulate carbon erosion under high heat fluxes, electron beam heating in the JUDITH facility has been used. In this paper, carbon erosion under energetic electron impact is modeled by the 3D thermomechanics code 'PEGASUS-3D'. The code is based on a crack generation induced by thermal stress. The particle emission observed in thermal shock experiments is a result of breaking bonds between grains caused by thermal stress. The comparison of calculations with experimental data from JUDITH shows good agreement for various incident power densities and pulse durations. A realistic mean failure stress has been found. Pre-heating of test specimens results in earlier onset of brittle destruction and enhanced particle loss in agreement with experiments

  16. Modelling of thermal shock experiments of carbon based materials in JUDITH

    Energy Technology Data Exchange (ETDEWEB)

    Ogorodnikova, O.V. [Forschungszentrum Juelich, EURATOM-Association, IWV-2, 52425 Juelich (Germany)]. E-mail: o.ogorodnikova@fz-juelich.de; Pestchanyi, S. [Forschungszentrum Karlsruhe, EURATOM-Associaton, IHM, 76021 Karlsruhe (Germany); Koza, Y. [Forschungszentrum Juelich, EURATOM-Association, IWV-2, 52425 Juelich (Germany); Linke, J. [Forschungszentrum Juelich, EURATOM-Association, IWV-2, 52425 Juelich (Germany)

    2005-03-01

    The interaction of hot plasma with material in fusion devices can result in material erosion and irreversible damage. Carbon based materials are proposed for ITER divertor armour. To simulate carbon erosion under high heat fluxes, electron beam heating in the JUDITH facility has been used. In this paper, carbon erosion under energetic electron impact is modeled by the 3D thermomechanics code 'PEGASUS-3D'. The code is based on a crack generation induced by thermal stress. The particle emission observed in thermal shock experiments is a result of breaking bonds between grains caused by thermal stress. The comparison of calculations with experimental data from JUDITH shows good agreement for various incident power densities and pulse durations. A realistic mean failure stress has been found. Pre-heating of test specimens results in earlier onset of brittle destruction and enhanced particle loss in agreement with experiments.

  17. Modelling of thermal shock experiments of carbon based materials in JUDITH

    Science.gov (United States)

    Ogorodnikova, O. V.; Pestchanyi, S.; Koza, Y.; Linke, J.

    2005-03-01

    The interaction of hot plasma with material in fusion devices can result in material erosion and irreversible damage. Carbon based materials are proposed for ITER divertor armour. To simulate carbon erosion under high heat fluxes, electron beam heating in the JUDITH facility has been used. In this paper, carbon erosion under energetic electron impact is modeled by the 3D thermomechanics code 'PEGASUS-3D'. The code is based on a crack generation induced by thermal stress. The particle emission observed in thermal shock experiments is a result of breaking bonds between grains caused by thermal stress. The comparison of calculations with experimental data from JUDITH shows good agreement for various incident power densities and pulse durations. A realistic mean failure stress has been found. Pre-heating of test specimens results in earlier onset of brittle destruction and enhanced particle loss in agreement with experiments.

  18. Experiments and analysis of thermal stresses around the nozzle of the reactor vessel

    International Nuclear Information System (INIS)

    Song, D.H.; Oh, J.H.; Song, H.K.; Park, D.S.; Shon, K.H.

    1981-01-01

    This report describes the results of analysis and experiments on the thermal stress around the reactor vessel nozzle performed to establish a capability of thermal stress analysis of pressure vessel subjected to thermal loadings. Firstly, heat conduction analysis during reactor design transients and analysis on the experimental model were performed using computer code FETEM-1 for the purpose of verification of FETEM-1 which was developed in 1979 and will be used to obtain the temperature distribution in a solid body under the steady-state and the transient conditions. The results of the analysis was compared to the results in the Stress Report of Kori-1 reactor vessel and those from experiments on the model, respectively

  19. Experiment and prediction on thermal conductivity of Al2O3/ZnO ...

    Indian Academy of Sciences (India)

    Administrator

    Experiment and prediction on thermal conductivity of Al2O3/ZnO nano thin film interface structure. PING YANG*, LIQIANG ZHANG, HAIYING YANG†, DONGJING LIU and XIALONG LI. Laboratory of Advanced Manufacturing and Reliability for MEMS/NEMS/OEDS,. School of Mechanical Engineering, Jiangsu University, ...

  20. 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

  1. New ANFO explosives made of ammonium nitrate of increased porosity and naphtha

    Energy Technology Data Exchange (ETDEWEB)

    Kutsarov, B.; Mavrodieva, R.; Ivanov, I.; Stoyanov, V.; Georgiev, N.; Krumov, I.; Katsarski, I.; Vakliev, I.

    1990-01-01

    Discusses results achieved by the KNIIPPI Niproruda Research Institute and the Osogovo enterprise in improving the quality of ANFO explosives. Ammonium nitrate with increased porosity was treated by water steam and wetting agents and then thermally treated. Naphtha in a quantity of up to 8% was then added to the ammonium nitrate to produce a powerful and stable explosive. The quality of explosive cartridges was tested first in the laboratory using the Schaffler apparatus. Test results were very satisfactory (better porosity, higher detonation velocity (2200-3600 m/s), better stability). Industrial experiments carried out in several underground mines also produced satisfactory results (better output in roadway drivage at lower operating cost and better safety). 8 refs.

  2. Design of 6 Mev linear accelerator based pulsed thermal neutron source: FLUKA simulation and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Patil, B.J., E-mail: bjp@physics.unipune.ac.in [Department of Physics, University of Pune, Pune 411 007 (India); Chavan, S.T.; Pethe, S.N.; Krishnan, R. [SAMEER, IIT Powai Campus, Mumbai 400 076 (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 411 007 (India); Dhole, S.D., E-mail: sanjay@physics.unipune.ac.in [Department of Physics, University of Pune, Pune 411 007 (India)

    2012-01-15

    The 6 MeV LINAC based pulsed thermal neutron source has been designed for bulk materials analysis. The design was optimized by varying different parameters of the target and materials for each region using FLUKA code. The optimized design of thermal neutron source gives flux of 3 Multiplication-Sign 10{sup 6}ncm{sup -2}s{sup -1} with more than 80% of thermal neutrons and neutron to gamma ratio was 1 Multiplication-Sign 10{sup 4}ncm{sup -2}mR{sup -1}. The results of prototype experiment and simulation are found to be in good agreement with each other. - Highlights: Black-Right-Pointing-Pointer The optimized 6 eV linear accelerator based thermal neutron source using FLUKA simulation. Black-Right-Pointing-Pointer Beryllium as a photonuclear target and reflector, polyethylene as a filter and shield, graphite as a moderator. Black-Right-Pointing-Pointer Optimized pulsed thermal neutron source gives neutron flux of 3 Multiplication-Sign 10{sup 6} n cm{sup -2} s{sup -1}. Black-Right-Pointing-Pointer Results of the prototype experiment were compared with simulations and are found to be in good agreement. Black-Right-Pointing-Pointer This source can effectively be used for the study of bulk material analysis and activation products.

  3. A new approach to designing reduced scale thermal-hydraulic experiments

    International Nuclear Information System (INIS)

    Lapa, Celso M.F.; Sampaio, Paulo A.B. de; Pereira, Claudio M.N.A.

    2004-01-01

    Reduced scale experiments are often employed in engineering because they are much cheaper than real scale testing. Unfortunately, though, it is difficult to design a thermal-hydraulic circuit or equipment in reduced scale capable of reproducing, both accurately and simultaneously, all the physical phenomena that occur in real scale and operating conditions. This paper presents a methodology to designing thermal-hydraulic experiments in reduced scale based on setting up a constrained optimization problem that is solved using genetic algorithms (GAs). In order to demonstrate the application of the methodology proposed, we performed some investigations in the design of a heater aimed to simulate the transport of heat and momentum in the core of a pressurized water reactor (PWR) at 100% of nominal power and non-accident operating conditions. The results obtained show that the proposed methodology is a promising approach for designing reduced scale experiments

  4. In-flight thermal experiments for LISA Pathfinder: Simulating temperature noise at the Inertial Sensors

    International Nuclear Information System (INIS)

    Armano, M; Audley, H; Born, M; Danzmann, K; Diepholz, I; Auger, G; Binetruy, P; Baird, J; Bortoluzzi, D; Brandt, N; Fitzsimons, E; Bursi, A; Caleno, M; Cavalleri, A; Cesarini, A; Dolesi, R; Ferroni, V; Cruise, M; Dunbar, N; Ferraioli, L

    2015-01-01

    Thermal Diagnostics experiments to be carried out on board LISA Pathfinder (LPF) will yield a detailed characterisation of how temperature fluctuations affect the LTP (LISA Technology Package) instrument performance, a crucial information for future space based gravitational wave detectors as the proposed eLISA. Amongst them, the study of temperature gradient fluctuations around the test masses of the Inertial Sensors will provide as well information regarding the contribution of the Brownian noise, which is expected to limit the LTP sensitivity at frequencies close to 1 mHz during some LTP experiments. In this paper we report on how these kind of Thermal Diagnostics experiments were simulated in the last LPF Simulation Campaign (November, 2013) involving all the LPF Data Analysis team and using an end-to-end simulator of the whole spacecraft. Such simulation campaign was conducted under the framework of the preparation for LPF operations. (paper)

  5. Daily Thermal Predictions of the AGR-1 Experiment with Gas Gaps Varying with Time

    Energy Technology Data Exchange (ETDEWEB)

    Grant Hawkes; James Sterbentz; John Maki; Binh Pham

    2012-06-01

    A new daily as-run thermal analysis was performed at the Idaho National Laboratory on the Advanced Gas Reactor (AGR) test experiment number one at the Advanced Test Reactor (ATR). This thermal analysis incorporates gas gaps changing with time during the irradiation experiment. The purpose of this analysis was to calculate the daily average temperatures of each compact to compare with experimental results. Post irradiation examination (PIE) measurements of the graphite holder and fuel compacts showed the gas gaps varying from the beginning of life. The control temperature gas gap and the fuel compact – graphite holder gas gaps were linearly changed from the original fabrication dimensions, to the end of irradiation measurements. A steady-state thermal analysis was performed for each daily calculation. These new thermal predictions more closely match the experimental data taken during the experiment than previous analyses. Results are presented comparing normalized compact average temperatures to normalized log(R/B) Kr-85m. The R/B term is the measured release rate divided by the predicted birth rate for the isotope Kr-85m. Correlations between these two normalized values are presented.

  6. Thermal neutron pulsed parameters in non-hydrogenous systems. Experiment for lead grains

    International Nuclear Information System (INIS)

    Drozdowicz, K.; Gabanska, B.; Kosik, M.; Krynicka, E.; Woznicka, U.; Zaleski, T.

    1997-01-01

    In Czubek's method of measurement of the thermal neutron macroscopic absorption cross section a two-region geometry is applied where the investigated sample is surrounded by an external moderator. Both regions in the measurements made up till now were hydrogenous, which means the same type of the thermal neutron transport properties. In the paper a theoretical consideration to use non-hydrogenous materials as the samples is presented. Pulsed neutron measurements have been performed on homogeneous material in a geometry of the classic experiment with the variable geometric buckling. Two decay constants have been measured for different cylindrical samples of small lead grains (a lead shot). (author)

  7. 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.

  8. The reactants equation of state for the tri-amino-tri-nitro-benzene (TATB) based explosive PBX 9502

    Science.gov (United States)

    Aslam, Tariq D.

    2017-07-01

    The response of high explosives (HEs), due to mechanical and/or thermal insults, is of great importance for both safety and performance. A major component of how an HE responds to these stimuli stems from its reactant equation of state (EOS). Here, the tri-amino-tri-nitro-benzene based explosive PBX 9502 is investigated by examining recent experiments. Furthermore, a complete thermal EOS is calibrated based on the functional form devised by Wescott, Stewart, and Davis [J. Appl. Phys. 98, 053514 (2005)]. It is found, by comparing to earlier calibrations, that a variety of thermodynamic data are needed to sufficiently constrain the EOS response over a wide range of thermodynamic state space. Included in the calibration presented here is the specific heat as a function of temperature, isobaric thermal expansion, and shock Hugoniot response. As validation of the resulting model, isothermal compression and isentropic compression are compared with recent experiments.

  9. Non-LTE considerations in spectral diagnostics of thermal transport and implosion experiments

    International Nuclear Information System (INIS)

    Epstein, R.; Skupsky, S.; Delettrez, J.; Yaakobi, B.

    1984-01-01

    Recent thermal-transport and target-implosion experiments have used the emission of radiation from highly-ionized ions to signal the advance of laser-driven heat fronts and to mark the trajectories and stagnation points of imploding shells. We examine the results of such experiments with particular attention given to non-LTE effects of non-Maxwellian electrons and of finite ionization times on the populations of signature-emitting atomic species and on the formation of signature spectra and x-ray images in these experiments

  10. Stress induced conditioning and thermal relaxation in the simulation of quasi-static compression experiments

    International Nuclear Information System (INIS)

    Scalerandi, M; Delsanto, P P; Johnson, P A

    2003-01-01

    Local interaction simulation approach simulations of the ultrasonic wave propagation in multi-grained materials have succeeded in reproducing most of the recently observed nonclassical nonlinear effects, such as stress-strain hysteresis and discrete memory in quasi-static experiments and a downwards shift of the resonance frequency and the generation of odd harmonics at specific amplitude rates in dynamics experiments. By including a simple mechanism of thermally activated random transitions, we can predict the occurrence of experimentally observed effects, such as the conditioning and relaxation of the specimen. Experiments are also suggested for a quantitative assessment of the validity of the model

  11. Stress induced conditioning and thermal relaxation in the simulation of quasi-static compression experiments

    CERN Document Server

    Scalerandi, M; Johnson, P A

    2003-01-01

    Local interaction simulation approach simulations of the ultrasonic wave propagation in multi-grained materials have succeeded in reproducing most of the recently observed nonclassical nonlinear effects, such as stress-strain hysteresis and discrete memory in quasi-static experiments and a downwards shift of the resonance frequency and the generation of odd harmonics at specific amplitude rates in dynamics experiments. By including a simple mechanism of thermally activated random transitions, we can predict the occurrence of experimentally observed effects, such as the conditioning and relaxation of the specimen. Experiments are also suggested for a quantitative assessment of the validity of the model.

  12. 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)

  13. Improved accuracy and precision in δ15 NAIR measurements of explosives, urea, and inorganic nitrates by elemental analyzer/isotope ratio mass spectrometry using thermal decomposition.

    Science.gov (United States)

    Lott, Michael J; Howa, John D; Chesson, Lesley A; Ehleringer, James R

    2015-08-15

    Elemental analyzer systems generate N(2) and CO(2) for elemental composition and isotope ratio measurements. As quantitative conversion of nitrogen in some materials (i.e., nitrate salts and nitro-organic compounds) is difficult, this study tests a recently published method - thermal decomposition without the addition of O(2) - for the analysis of these materials. Elemental analyzer/isotope ratio mass spectrometry (EA/IRMS) was used to compare the traditional combustion method (CM) and the thermal decomposition method (TDM), where additional O(2) is eliminated from the reaction. The comparisons used organic and inorganic materials with oxidized and/or reduced nitrogen and included ureas, nitrate salts, ammonium sulfate, nitro esters, and nitramines. Previous TDM applications were limited to nitrate salts and ammonium sulfate. The measurement precision and accuracy were compared to determine the effectiveness of converting materials containing different fractions of oxidized nitrogen into N(2). The δ(13) C(VPDB) values were not meaningfully different when measured via CM or TDM, allowing for the analysis of multiple elements in one sample. For materials containing oxidized nitrogen, (15) N measurements made using thermal decomposition were more precise than those made using combustion. The precision was similar between the methods for materials containing reduced nitrogen. The %N values were closer to theoretical when measured by TDM than by CM. The δ(15) N(AIR) values of purchased nitrate salts and ureas were nearer to the known values when analyzed using thermal decomposition than using combustion. The thermal decomposition method addresses insufficient recovery of nitrogen during elemental analysis in a variety of organic and inorganic materials. Its implementation requires relatively few changes to the elemental analyzer. Using TDM, it is possible to directly calibrate certain organic materials to international nitrate isotope reference materials without off

  14. Thermal stability of morpholine, AMP and sarcosine in PWR secondary systems. Laboratory and loop experiments

    International Nuclear Information System (INIS)

    Feron, D.; Lambert, I.

    1991-01-01

    Laboratory and loop tests have been carried out in order to investigate the thermal stability of three amines (morpholine, AMP and sarcosine) in PWR secondary conditions. Laboratory experiments have been performed in a titanium autoclave at 300 deg C. The results pointed out high thermal decomposition rates of AMP and sarcosine. A decomposition mechanism is proposed for the 3 amines. Loop tests have been performed in order to compare steam cycle conditioning with ammonia, morpholine and AMP. The amine concentrations and the decomposition products such as acetate and formate have been followed around the secondary circuit of the ORION loop which reproduces the main physico-chemical characteristics of a PWR secondary circuit. These concentrations are reported together with the evolution of cationic conductivities. The influence of oxygen concentration on amine thermal stability has been observed. Results are expressed also in terms of decomposition rates and of relative volatility

  15. 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.

  16. Climate Chamber Experiment-Based Thermal Analysis and Design Improvement of Traditional Huizhou Masonry Walls

    Directory of Open Access Journals (Sweden)

    Ling Dong

    2018-03-01

    Full Text Available Supported by thousands of years of history, traditional Huizhou buildings have played a vital role, both functionally and culturally, as residential buildings in China. Masonry walls are one of the key building components of a Huizhou building; however, the traditional Huizhou masonry wall structure, predominantly a hollow brick structure, cannot meet the local building energy code requirements, and thus needs to be improved. Within this context, the present research measures the actual thermal performance of traditional Huizhou masonry walls for historical buildings and new-built buildings, which results in mean thermal transmittances of 1.892 W/m2·K and 2.821 W/m2·K, respectively, while the local building energy code requires a minimum thermal transmittance of 1.500 W/m2·K. In order to improve the thermal performance of traditional Huizhou masonry walls, four design scenarios for wall insulation are proposed and tested in a climate chamber: (1 hollow brick wall with inorganic interior insulation mortar, (2 solid brick wall with inorganic interior insulation mortar, (3 hollow brick wall with foamed concrete, and (4 hollow brick wall with foamed concrete plus inorganic interior insulation mortar. The experiment results indicate that, among the four proposed design scenarios, only scenario 4 can significantly improve the thermal performance of Huizhou masonry walls and meet the building energy code requirements, with a mean thermal transmittance of 1.175 W/m2·K. This research lays the foundation for improving the thermal performance of Huizhou masonry walls with new insulation and construction technology, thereby helping to improve the quality of life of Huizhou residents while respecting the cultural significance of the traditional Huizhou building.

  17. A two-compartment thermal-hydraulic experiment (LACE-LA4) analyzed by ESCADRE code

    International Nuclear Information System (INIS)

    Passalacqua, R.

    1994-01-01

    Large scale experiments show that whenever a Loss of Coolant Accident (LOCA) occurs, water pools are generated. Stratifications of steam saturated gas develop above water pools causing a two-compartment thermal-hydraulics. The LACE (LWR Advanced Containment Experiment) LA4 experiment, performed at the Hanford Engineering Development Laboratory (HEDL), exhibited a strong stratification, at all times, above a growing water pool. JERICHO and AEROSOLS-B2 are part of the ESCADRE code system (Ensemble de Systemes de Codes d'Analyse d'accident Des Reacteurs A Eau), a tool for evaluating the response of a nuclear plant to severe accidents. These two codes are here used to simulate respectively the thermal-hydraulics and the associated aerosol behavior. Code results have shown that modelling large containment thermal-hydraulics without taking account of the stratification phenomenon leads to large overpredictions of containment pressure and temperature. If the stratification is modelled as a zone with a higher steam condensation rate and a higher thermal resistance, ESCADRE predictions match quite well experimental data. The stratification thermal-hydraulics is controlled by power (heat fluxes) repartition in the lower compartment between the water pool and the nearby walls. Therefore the total, direct heat exchange between the two compartment is reduced. Stratification modelling is believed to be important for its influence on aerosol behavior: aerosol deposition through the inter-face of the two subcompartments is improved by diffusiophoresis and thermophoresis. In addition the aerosol concentration gradient, through the stratification, will cause a driving force for motion of smaller particles towards the pool. (author)

  18. Large-scale thermal-shock experiments with clad and unclad steel cylinders

    International Nuclear Information System (INIS)

    Cheverton, R.D.

    1992-01-01

    Flaw behavior trends associated with pressurized-thermal-shock (PTS) loading of pressurized-water-reactor pressure vessels have been under investigation at the Oak Ridge National Laboratory for nearly 20 years. During that time, twelve thermal-shock experiments with thick-walled (152 mm) steel cylinders were conducted as a part of the investigations. The first eight experiments were conducted with unclad cylinders initially containing shallow (8--19 mm) two-dimensional and semicircular inner-surface flaws. These experiments demonstrated, in good agreement with linear elastic fracture mechanics, crack initiation and arrest, a series of initiation/arrest events with deep penetration of the wall, long crack jumps, arrest with the stress intensity factor (K I ) increasing with crack depth, extensive surface extension of an initially short and shallow (semicircular) flaw, and warm prestressing with K I ≤ 0. The remaining four experiments were conducted with clad cylinders containing initially shallow (19--24 mm) semielliptical subclad and surface flaws at the inner surface. In the first of these experiments one of six equally spaced (60 degrees) open-quotes identicalclose quotes subclad flaws extended nearly the length of the cylinder (1,220 mm) beneath the cladding (no crack extension into the cladding) and nearly 50% of the wall, radially. For the final experiment, four of the semielliptical subclad flaws that had not propagated previously were converted to surface flaws, and they experienced extensive extension beneath the cladding with no cracking of the cladding. Information from this series of thermal-shock experiments is being used in the evaluation of the PTS issue

  19. Crack propagation behavior of TiN coatings by laser thermal shock experiments

    International Nuclear Information System (INIS)

    Choi, Youngkue; Jeon, Seol; Jeon, Min-seok; Shin, Hyun-Gyoo; Chun, Ho Hwan; Lee, Youn-seoung; Lee, Heesoo

    2012-01-01

    Highlights: ► The crack propagation behavior of TiN coating after laser thermal shock experiment was observed by using FIB and TEM. ► Intercolumnar cracks between TiN columnar grains were predominant cracking mode after laser thermal shock. ► Cracks were propagated from the coating surface to the substrate at low laser pulse energy and cracks were originated at coating-substrate interface at high laser pulse energy. ► The cracks from the interface spread out transversely through the weak region of the columnar grains by repetitive laser shock. - Abstract: The crack propagation behavior of TiN coatings, deposited onto 304 stainless steel substrates by arc ion plating technique, related to a laser thermal shock experiment has been investigated using focused ion beam (FIB) and transmission electron microscopy (TEM). The ablated regions of TiN coatings by laser ablation system have been investigated under various conditions of pulse energies and number of laser pulses. The intercolumnar cracks were predominant cracking mode following laser thermal shock tests and the cracks initiated at coating surface and propagated in a direction perpendicular to the substrate under low loads conditions. Over and above those cracks, the cracks originated from coating-substrate interface began to appear with increasing laser pulse energy. The cracks from the interface also spread out transversely through the weak region of the columnar grains by repetitive laser shock.

  20. Thermal calculations pertaining to experiments in the Yucca Mountain Exploratory Shaft

    International Nuclear Information System (INIS)

    Montan, D.N.

    1986-03-01

    A series of thermal calculations have been presented that appear to satisfy the needs for design of the Yucca Mountain Exploratory Shaft Tests. The accuracy of the modeling and calculational techniques employed probably exceeds the accuracy of the thermal properties used. The rather close agreement between simple analytical methods (the PLUS Family) and much more complex methods (TRUMP) suggest that the PLUS Family might be appropriate during final design to model, in a single calculation, the entire test array and sequence. Before doing further calculations it is recommended that all available thermal property information be critically evaluated to determine ''best'' values to be used for conductivity and saturation. Another possibility is to design one or more of the test sequences to approximately duplicate the early phase of Heater Test 1. In that experiment an unplanned power outage for about two days that occurred a week into the experiment gave extremely useful data from which to determine the conductivity and diffusivity. In any case we urge that adequate, properly calibrated instrumentation with data output available on a quasi-real time basis be installed. This would allow us to take advantage of significant power changes (planned or not) and also help ''steer'' the tests to desired temperatures. Finally, it should be kept in mind that the calculations presented here are strictly thermal. No hydrothermal effects due to liquid and vapor pressures have been considered

  1. 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

  2. CFX-10 Analysis of the High Temperature Thermal- Chemical Experiment (CS28-2)

    International Nuclear Information System (INIS)

    Kim, Hyoung Tae; Park, Joo Hwan; Rhee, Bo Wook

    2008-02-01

    A Computational Fluid Dynamics (CFD) model of a post-blowdown fuel channel analysis for aged CANDU reactors with crept pressure tube has been developed, and validated against a high temperature thermal-chemical experiment: CS28-2. The CS28-2 experiment is one of three series of experiments to simulate the thermal-chemical behavior of a 28-element fuel channel at a high temperature and a low steam flow rate which may occur in severe accident conditions such as a LBLOCA (Large Break Loss of Coolant Accident) of CANDU reactors. Pursuant to the objective of this study, the current study has focused on understanding the involved phenomena such as the thermal radiation and convection heat transfer, and the high temperature zirconium-steam reaction in a multi-ring geometry. Therefore, a zirconium-steam oxidation model based on a parabolic rate law was implemented into the CFX-10 code, which is a commercial CFD code offered from ANSYS Inc., and other heat transfer mechanisms in the 28-element fuel channel were modeled by the original CFX-10 heat transfer packages. To assess the capability of the CFX-10 code to model the thermal-chemical behavior of the 28-element fuel channel, the measured temperatures of the Fuel Element Simulators (FES) of three fuel rings in the test bundle and the pressure tube, and the hydrogen production in the CS28-2 experiment were compared with the CFX-10 predictions. In spite of some discrepancy between the measurement data and CFX results, it was found that the CFX-10 prediction based on the Urbanic-Heidrick correlation of the zirconium-steam reaction as well as the Discrete Transfer Model for a radiation heat transfer among the FES of three rings and the pressure tube are quite accurate and sound even for the offset a cluster fuel bundle of an aged fuel channel

  3. Thermal shock experiment analysis, the use of crack arrest toughness measurements

    International Nuclear Information System (INIS)

    Miannay, D.; Pellissier-Tanon, A.; Chavaillard, J.P.

    1984-06-01

    The main purpose of thermal shock experiment is to assess the procedure codified in the ASME XI appendix 1 or RCC-M-B appendix ZG, and allow comparisons with numerical simulations. The analysis of the integrity of the PWR vessel belt line under accidental transients is based on reference curves. The test-piece is a cylinder of SA 508 cl.3 steel. Arrest toughness measured agrees with reference curve

  4. CFX-10 Analysis of the High Temperature Thermal- Chemical Experiment (CS28-2)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Tae; Park, Joo Hwan; Rhee, Bo Wook

    2008-02-15

    A Computational Fluid Dynamics (CFD) model of a post-blowdown fuel channel analysis for aged CANDU reactors with crept pressure tube has been developed, and validated against a high temperature thermal-chemical experiment: CS28-2. The CS28-2 experiment is one of three series of experiments to simulate the thermal-chemical behavior of a 28-element fuel channel at a high temperature and a low steam flow rate which may occur in severe accident conditions such as a LBLOCA (Large Break Loss of Coolant Accident) of CANDU reactors. Pursuant to the objective of this study, the current study has focused on understanding the involved phenomena such as the thermal radiation and convection heat transfer, and the high temperature zirconium-steam reaction in a multi-ring geometry. Therefore, a zirconium-steam oxidation model based on a parabolic rate law was implemented into the CFX-10 code, which is a commercial CFD code offered from ANSYS Inc., and other heat transfer mechanisms in the 28-element fuel channel were modeled by the original CFX-10 heat transfer packages. To assess the capability of the CFX-10 code to model the thermal-chemical behavior of the 28-element fuel channel, the measured temperatures of the Fuel Element Simulators (FES) of three fuel rings in the test bundle and the pressure tube, and the hydrogen production in the CS28-2 experiment were compared with the CFX-10 predictions. In spite of some discrepancy between the measurement data and CFX results, it was found that the CFX-10 prediction based on the Urbanic-Heidrick correlation of the zirconium-steam reaction as well as the Discrete Transfer Model for a radiation heat transfer among the FES of three rings and the pressure tube are quite accurate and sound even for the offset a cluster fuel bundle of an aged fuel channel.

  5. Thermal hydraulic behavior of sub-assembly local blockage in China experiment fast reactor

    International Nuclear Information System (INIS)

    Yang Zhimin

    2000-01-01

    The geometrical parameter ratio of pitch to diameter of China Experiment Fast Reactor (CEFR) subassembly is 1,167. To address the thermal hydraulic behavior of subassembly local blockage which may be caused by deformation of cladding due to severe swelling and thermal stresses and by space swirl loosening etc., the porous numerical model and SIMPLE-P code used to solve Navier-Stokes and energy equations in porous medium was developed, and the bundle experiment with 19 pins with 24 subchannels blocked in the sodium coolant was carried on in China Institute of Atomic Energy (CIAE). The comparison of code predictions against experiments (including non-blockage and ten blockage conditions) seems well. The thermal hydraulic behavior of fuel subassembly with 61 fuel pins blockage of CEFR is calculated with SIMPLE-P code. The results indicate that the maximum temperature is 815 deg. C when the blockage area is about 37% (54 central subchannels are blocked). In this case the cladding won't be damaged and no sodium coolant boiling takes place. (author)

  6. Simulation of TROI steam explosion behaviour using the COMETA code

    International Nuclear Information System (INIS)

    Arun Kumar Nayak; Hyun Sun Park; Bal Raj Sehgal; Alessandro Annunziato

    2005-01-01

    Full text of publication follows: During a severe accident in a nuclear reactor, the core can melt and the molten corium while interacting with water may cause an energetic fuel coolant interaction which is known as steam explosion. Such phenomena can occur inside the reactor vessel during flooding of a degraded core or when molten corium falls into the lower head filled with water. Similar phenomena may occur outside the reactor vessel when molten corium is ejected into a flooded reactor cavity or into the flooded containment after the vessel failure. The interaction of molten corium with water is one of the most complex thermal hydraulic and chemical phenomena. Recently in the TROI test series carried out at KAERI (Korean Atomic Energy Research Institute) in Korea, steam explosions were observed. In those tests, the UO 2 /ZrO 2 compositions were close to that of prototypic case. In this paper, we have numerically simulated the melt coolant interaction of TROI tests using the computer code, COMETA (Core MElt Thermalhydraulic Analysis) developed by JRC (Joint Research Center), at Ispra in Italy. The COMETA code was primarily developed to analyse, with sufficient detail, both the thermal-hydraulics and the fuel fragmentation phenomena during the melt quenching tests as conducted in the FARO facility. The code solves the conservation equations of mass, momentum and energy for the fluid using a conventional two-fluid model. Fuel fragmentation model considers the molten jet, its break up in drops and accumulation as fused-debris on the bottom. An explicit coupling between the thermal hydraulics and fuel fragmentation for the energy transfer is considered. The code has been extensively validated in the past for melt quenching in a series of experiments in the FARO facility. In this work, we first simulated the pre-mix and triggering phases of the TROI-13 tests for which the test data were available. The melt jet trajectory, void fraction and pressure profile were

  7. 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.

  8. 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.)

  9. 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)

  10. TMX tandem-mirror experiments and thermal-barrier theoretical studies

    International Nuclear Information System (INIS)

    Simonen, T.C.; Baldwin, D.E.; Allen, S.L.

    1982-01-01

    This paper describes recent analysis of energy confinement in the Tandem Mirror Experiment (TMX). TMX data also indicates that warm plasma limits the amplitude of the anisotropy driven Alfven ion cyclotron (AIC) mode. Theoretical calculations show strong AIC stabilization with off-normal beam injection as planned in TMX-U and MFTF-B. This paper reports results of theoretical analysis of hot electrons in thermal barriers including electron heating calculations by Monte Carlo and Fokker-Planck codes and analysis of hot electron MHD and microinstability. Initial results from the TMX-U experiment are presented which show the presence of sloshing ions

  11. Set of thermal neutron-scattering experiments for the Weapons Neutron Research Facility

    International Nuclear Information System (INIS)

    Brugger, R.M.

    1975-12-01

    Six classes of experiments form the base of a program of thermal neutron scattering at the Weapons Neutron Research (WNR) Facility. Three classes are to determine the average microscopic positions of atoms in materials and three are to determine the microscopic vibrations of these atoms. The first three classes concern (a) powder sample neutron diffraction, (b) small angle scattering, and (c) single crystal Laue diffraction. The second three concern (d) small kappa inelastic scattering, (e) scattering surface phonon measurements, and (f) line widths. An instrument to couple with the WNR pulsed source is briefly outlined for each experiment

  12. 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...

  13. Thermal experience during embryogenesis contributes to the induction of dwarfism in whitefish Coregonus lavaretus.

    Science.gov (United States)

    Steinbacher, Peter; Wanzenböck, Josef; Brandauer, Magdalena; Holper, Raphael; Landertshammer, Jasmin; Mayr, Magdalena; Platzl, Christian; Stoiber, Walter

    2017-01-01

    Ecotype pairs provide well-suited model systems for study of intraspecific phenotypical diversification of animals. However, little is still known about the processes that account for the development of different forms and sizes within a species, particularly in teleosts. Here, embryos of a normal-growing 'large' form and a dwarf form of whitefish Coregonus lavaretus were incubated at two temperatures that are usually experienced at their own spawning sites (2°C for the normal and 6°C for the dwarf form). All fish were subjected to similar thermal treatment after hatching. The present data demonstrate for the first time that different thermal experience in embryonic life has lasting effects on body and muscle growth of this ecotype pair and contributes to the development of the dwarf form. Thus, juvenile fish of the regular form are much smaller and have less muscle mass when pre-hatching thermal conditions were similar to those typical for the spawning sites of the dwarf form (6°C) than when subjected to conditions of their own spawning sites (2°C). Surprisingly, fish of the dwarf form exhibit a similar pattern of response to thermal history (2°-fish much larger than 6°-fish), indicating that in their case, normal spawning site temperature (6°C) is indeed likely to act as a growth limiting factor. Results also demonstrate that the hypertrophic and hyperplastic muscle growth modes are similarly affected by thermal history. Immunolabelling experiments for Pax7, H3P and Mef2 provide evidence that the cellular mechanisms behind the increased growth rates after cold incubation in both ecotypes are increased proliferation and reduced differentiation rates of muscle precursor cells. This is of major significance to aspects of ecological and developmental biology and from the evolutionary perspective.

  14. Thermal experience during embryogenesis contributes to the induction of dwarfism in whitefish Coregonus lavaretus.

    Directory of Open Access Journals (Sweden)

    Peter Steinbacher

    Full Text Available Ecotype pairs provide well-suited model systems for study of intraspecific phenotypical diversification of animals. However, little is still known about the processes that account for the development of different forms and sizes within a species, particularly in teleosts. Here, embryos of a normal-growing 'large' form and a dwarf form of whitefish Coregonus lavaretus were incubated at two temperatures that are usually experienced at their own spawning sites (2°C for the normal and 6°C for the dwarf form. All fish were subjected to similar thermal treatment after hatching. The present data demonstrate for the first time that different thermal experience in embryonic life has lasting effects on body and muscle growth of this ecotype pair and contributes to the development of the dwarf form. Thus, juvenile fish of the regular form are much smaller and have less muscle mass when pre-hatching thermal conditions were similar to those typical for the spawning sites of the dwarf form (6°C than when subjected to conditions of their own spawning sites (2°C. Surprisingly, fish of the dwarf form exhibit a similar pattern of response to thermal history (2°-fish much larger than 6°-fish, indicating that in their case, normal spawning site temperature (6°C is indeed likely to act as a growth limiting factor. Results also demonstrate that the hypertrophic and hyperplastic muscle growth modes are similarly affected by thermal history. Immunolabelling experiments for Pax7, H3P and Mef2 provide evidence that the cellular mechanisms behind the increased growth rates after cold incubation in both ecotypes are increased proliferation and reduced differentiation rates of muscle precursor cells. This is of major significance to aspects of ecological and developmental biology and from the evolutionary perspective.

  15. 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)

  16. 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.)

  17. Some properties of explosive mixtures containing peroxides Part II. Relationships between detonation parameters and thermal reactivity of the mixtures with triacetone triperoxide.

    Science.gov (United States)

    Zeman, Svatopluk; Bartei, Cécile

    2008-06-15

    This study concerns mixtures of triacetone triperoxide (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane, TATP) and ammonium nitrate (AN) with added water (W), as the case may be, and two dry mixtures of TATP with urea nitrate (UN). Relative performances (RP) of the mixtures and their individual components, relative to TNT, were determined by means of ballistic mortar. Thermal reactivity of these mixtures was examined by means of differential thermal analysis and the data were analyzed according to the modified Kissinger method (the peak temperature was replaced by the temperature of decomposition onset in this case). The reactivity, expressed as the EaR(-1) slopes of the Kissinger relationship, correlates with the squares of the calculated detonation velocities for the charge density of 1000 kg m(-3) of the studied energetic materials. Similarly, the relationships between the EaR(-1) values and RP have been found. While the first mentioned correlation (modified Evans-Polanyi-Semenov equation) is connected with the primary chemical micro-mechanism of the mixtures detonation, the relationships in the second case should be connected with the thermochemical aspects of this detonation.

  18. Verification of fire and explosion accident analysis codes (facility design and preliminary results)

    International Nuclear Information System (INIS)

    Gregory, W.S.; Nichols, B.D.; Talbott, D.V.; Smith, P.R.; Fenton, D.L.

    1985-01-01

    For several years, the US Nuclear Regulatory Commission has sponsored the development of methods for improving capabilities to analyze the effects of postulated accidents in nuclear facilities; the accidents of interest are those that could occur during nuclear materials handling. At the Los Alamos National Laboratory, this program has resulted in three computer codes: FIRAC, EXPAC, and TORAC. These codes are designed to predict the effects of fires, explosions, and tornadoes in nuclear facilities. Particular emphasis is placed on the movement of airborne radioactive material through the gaseous effluent treatment system of a nuclear installation. The design, construction, and calibration of an experimental ventilation system to verify the fire and explosion accident analysis codes are described. The facility features a large industrial heater and several aerosol smoke generators that are used to simulate fires. Both injected thermal energy and aerosol mass can be controlled using this equipment. Explosions are simulated with H 2 /O 2 balloons and small explosive charges. Experimental measurements of temperature, energy, aerosol release rates, smoke concentration, and mass accumulation on HEPA filters can be made. Volumetric flow rate and differential pressures also are monitored. The initial experiments involve varying parameters such as thermal and aerosol rate and ventilation flow rate. FIRAC prediction results are presented. 10 figs

  19. 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)

  20. Proceedings of the specialists meeting on experience with thermal fatigue in LWR piping caused by mixing and stratification

    International Nuclear Information System (INIS)

    1998-01-01

    This specialists meeting on experience with thermal fatigue in LWR piping caused by mixing and stratification, was held in June 1998 in Paris. It included five sessions. Session 1: operating experience (7 papers): Historical perspective; EDF experience with local thermohydraulic phenomena in PWRs: impacts and strategies; Thermal fatigue in safety injection lines of French PWRs: technical problems, regulatory requirements, concerns about other areas; US NRC Regulatory perspective on unanticipated thermal fatigue in LWR piping; Failure to the Residual Heat Removal system suction line pipe in Genkai unit 1 caused by thermal stratification cycling; Emergency Core Cooling System pipe crack incident at Tihange unit 1; Two leakages induced by thermal stratification at the Loviisa power plant). Session 2: thermal hydraulic phenomena (5 papers): Thermal stratification in small pipes with respect to fatigue effects and so called 'Banana effect'; Thermal stratification in the surge line of the Korean next generation reactor; Thermal stratification in horizontal pipes investigated in UPTF-TRAM and HDR facilities; Research on thermal stratification in un-isolable piping of reactor pressure boundary; Thermal mixing phenomena in piping systems: 3D numerical simulation and design considerations. Session 3: response of material and structure (5 papers): Fatigue induced by thermal stratification, Results of tests and calculations of the COUFAST model; Laboratory simulation of thermal fatigue cracking as a basis for verifying life models; Thermo-mechanical analysis methods for the conception and the follow up of components submitted to thermal stratification transients; Piping analysis methods of a PWR surge line for stratified flow; The thermal stratification effect on surge lines, The VVER estimation. Session 4: monitoring aspects (4 papers): Determination of the thermal loadings affecting the auxiliary lines of the reactor coolant system in French PWR plants; Expected and

  1. Sorbent Film-Coated Passive Samplers for Explosives Vapour Detection Part A: Materials Optimisation and Integration with Analytical Technologies.

    Science.gov (United States)

    McEneff, Gillian L; Murphy, Bronagh; Webb, Tony; Wood, Dan; Irlam, Rachel; Mills, Jim; Green, David; Barron, Leon P

    2018-04-11

    A new thin-film passive sampler is presented as a low resource dependent and discrete continuous monitoring solution for explosives-related vapours. Using 15 mid-high vapour pressure explosives-related compounds as probes, combinations of four thermally stable substrates and six film-based sorbents were evaluated. Meta-aramid and phenylene oxide-based materials showed the best recoveries from small voids (~70%). Analysis was performed using liquid chromatography-high resolution accurate mass spectrometry which also enabled tentative identification of new targets from the acquired data. Preliminary uptake kinetics experiments revealed plateau concentrations on the device were reached between 3-5 days. Compounds used in improvised explosive devices, such as triacetone triperoxide, were detected within 1 hour and were stably retained by the sampler for up to 7 days. Sampler performance was consistent for 22 months after manufacture. Lastly, its direct integration with currently in-service explosives screening equipment including ion mobility spectrometry and thermal desorption mass spectrometry is presented. Following exposure to several open environments and targeted interferences, sampler performance was subsequently assessed and potential interferences identified. High-security building and area monitoring for concealed explosives using such cost-effective and discrete passive samplers can add extra assurance to search routines while minimising any additional burden on personnel or everyday site operation.

  2. 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.

  3. Contained fission explosion breeder reactor system

    International Nuclear Information System (INIS)

    Juhl, N.H.; Marwick, E.F.

    1983-01-01

    A reactor system for producing useful thermal energy and valuable isotopes, such as plutonium-239, uranium-233, and/or tritium, in which a pair of sub-critical masses of fissile and fertile actinide slugs are propelled into an ellipsoidal pressure vessel. The propelled slugs intercept near the center of the chamber where the concurring slugs become a more than prompt configuration thereby producing a fission explosion. Re-useable accelerating mechanisms are provided external of the vessel for propelling the slugs at predetermined time intervals into the vessel. A working fluid of lean molten metal slurry is injected into the chamber prior to each explosion for the attenuation of the explosion's effects, for the protection of the chamber's walls, and for the absorbtion of thermal energy and debris from the explosion. The working fluid is injected into the chamber in a pattern so as not to interfere with the flight paths of the slugs and to maximize the concentration of working fluid near the chamber's center. The heated working fluid is drained from the vessel and is used to perform useful work. Most of the debris from the explosion is collected as precipitate and is used for the manufacture of new slugs

  4. Development of Thermal Radiation Experiments Kit Based on Data Logger for Physics Learning Media

    Science.gov (United States)

    Permana, H.; Iswanto, B. H.

    2018-04-01

    Thermal Radiation Experiments Kit (TREK) based on data logger for physics learning media was developed. TREK will be used as a learning medium on the subject of Temperature and Heat to explain the concept of emissivity of a material in grade XI so that it can add variations of experiments which are commonly done such as thermal expansion, transfer of thermal energy (conduction, convection, and radiation), and specific heat capacity. DHT11 sensor is used to measure temperature and microcontroller Arduino-uno used as data logger. The object tested are in the form of coated glass thin films and aluminum with different colors. TREK comes with a user manual and student worksheet (LKS) to make it easier for teachers and students to use. TREK was developed using the ADDIE Development Model (Analyze, Design, Development, Implementation, and Evaluation). And validated by experts, physics teachers, and students. Validation instrument is a questionnaire with a five-item Likert response scale with reviewed aspect coverage: appropriate content and concepts, design, and user friendly. The results showed that TREK was excellent (experts 88.13%, science teachers 95.68%, and students 85.77%).

  5. Experiment study on the thermal properties of paraffin/kaolin thermal energy storage form-stable phase change materials

    International Nuclear Information System (INIS)

    Lv, Peizhao; Liu, Chenzhen; Rao, Zhonghao

    2016-01-01

    Highlights: • Different particle sizes of kaolin were employed to load paraffin. • The effects and reasons of particle size on thermal conductivity were studied. • Thermal property and thermal stability of the composites were investigated. • The leakage and thermal storage and release rate of the composites were studied. • The effect of vacuum impregnation method on thermal conductivity was investigated. - Abstract: In this paper, different particle sizes of kaolin were employed to incorporate paraffin via vacuum impregnation method. The paraffin/kaolin composites were characterized by Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimeter (DSC) and Thermogravimetry (TG). The results showed that the paraffin/kaolin composite with the largest particle size of kaolin (K4) has the highest thermal conductivity (0.413 W/(m K) at 20 °C) among the diverse composites. The latent heat capacity of paraffin/K4 is 119.49 J/g and the phase change temperature is 62.4 °C. In addition, the thermal properties and thermal conductivities of paraffin/K4 with different mass fraction of K4 (0–60%) were investigated. The thermal conductivities of the composites were explained in microcosmic field. The phonon mean free path determines the thermal conductivity, and it can be significantly affected by temperature and the contact surface area. The leaks, thermal storage and release properties of pure paraffin and paraffin/kaolin composites were investigated and the composites presented good thermal stabilities.

  6. 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

  7. 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...

  8. 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)

  9. 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.

  10. 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)

  11. 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)

  12. Small scale thermal-hydraulic experiment for stable operation of a pius-type reactor

    International Nuclear Information System (INIS)

    Tasaka, K.; Tamaki, M.; Imai, S.; Irianto, I.D.; Tsuji, Y.; Kukita, Y.

    1994-01-01

    Thermal-hydraulic experiments using a small-scale atmospheric pressure test loop have been performed for the Process Inherent Ultimate Safety (PIUS)-type reactor to develop the new pump speed feedback control system. Three feedback control systems based on the measurement of flow rate, differential pressure, and fluid temperature distribution in the lower density lock have been proposed and confirmed by a series of experiments. Each of the feedback control systems had been verified in the simulation experiment such as a start-up simulation test. The automatic pump speed control based on the fluid temperature at the lower density lock was quite effective to maintain the stratified interface between primary water and borated pool water for stable operation of the reactor. (author)

  13. 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.

  14. Experiment Investigation on Electrical and Thermal Performances of a Semitransparent Photovoltaic/Thermal System with Water Cooling

    Directory of Open Access Journals (Sweden)

    Guiqiang Li

    2014-01-01

    Full Text Available Different from the semitransparent building integrated photovoltaic/thermal (BIPV/T system with air cooling, the semitransparent BIPV/T system with water cooling is rare, especially based on the silicon solar cells. In this paper, a semitransparent photovoltaic/thermal system (SPV/T with water cooling was set up, which not only would provide the electrical power and hot water, but also could attain the natural illumination for the building. The PV efficiency, thermal efficiency, and exergy analysis were all adopted to illustrate the performance of SPV/T system. The results showed that the PV efficiency and the thermal efficiency were about 11.5% and 39.5%, respectively, on the typical sunny day. Furthermore, the PV and thermal efficiencies fit curves were made to demonstrate the SPV/T performance more comprehensively. The performance analysis indicated that the SPV/T system has a good application prospect for building.

  15. Thermal and Structural Analysis of Beamline Components in the Mu2e Experiment

    International Nuclear Information System (INIS)

    Martin, Luke Daniel

    2016-01-01

    Fermi National Accelerator Laboratory will be conducting the high energy particle physics experiment Muons to Electrons (Mu2e). In this experiment, physicists will attempt to witness and understand an ultra-rare process which is the conversion of a muon into the lighter mass electron, without creating additional neutrinos. The experiment is conducted by first generating a proton beam which will be collided into a target within the production solenoid (PS). This creates a high-intensity muon beam which passes through a transport solenoid (TS) and into the detector solenoid (DS). In the detector solenoid the muons will be stopped in an aluminum target and a series of detectors will measure the electrons produced. These components have been named the DS train since they are coupled and travel on a rail system when being inserted or extracted from the DS. To facilitate the installation and removal of the DS train, a set of external stands and a support stand for the instrumentation feed-through bulkhead (IFB) have been designed. Full analysis of safety factors and performance of these two designs has been completed. The detector solenoid itself will need to be maintained to a temperature of 22°C ± 10°C. This will minimize thermal strain and ensure the accurate position of the components is maintained to the tolerance of 2 mm. To reduce the thermal gradient, a passive heating system has been developed and reported.

  16. Validation experiments of nuclear characteristics of the fast-thermal system HERBE

    International Nuclear Information System (INIS)

    Pesic, M.; Zavaljevski, N.; Marinkovic, P.; Stefanovis, D.; Nikolic, D.; Avdic, S.

    1992-01-01

    In 1988/90 a coupled fast-thermal system HERBE at RB reactor, based on similar facilities, is designed and realized. Fast core of HERBE is built of natural U fuel in RB reactor center surrounded by the neutron filter and neutron converter located in an independent Al tank. Fast zone is surrounded by thermal neutron core driver. Designed nuclear characteristics of HERBE core are validated in the experiments described in the paper. HERBE cell parameters were calculated with developed computer codes: VESNA and DENEB. HERBE system criticality calculation are performed with 4G 2D RZ computer codes GALER and TWENTY GRAND, 1D multi-group AVERY code and 3D XYZ few-group TRITON computer code. The experiments for determination of critical level, dρ/dH, and reactivity of safety rods are accomplished in order to validate calculation results. Specific safety experiment is performed in aim to determine reactivity of flooded fast zone in possible accident. A very good agreements with calculation results are obtained and the validation procedures are presented. It is expected that HERBE will offer qualitative new opportunities for work with fast neutrons at RB reactor including nuclear data determination. (author)

  17. Numerical experiments on thermal convection of highly compressible fluids with variable viscosity and thermal conductivity: Implications for mantle convection of super-Earths

    Science.gov (United States)

    Kameyama, Masanori; Yamamoto, Mayumi

    2018-01-01

    We conduct a series of numerical experiments of thermal convection of highly compressible fluids in a two-dimensional rectangular box, in order to study the mantle convection on super-Earths. The thermal conductivity and viscosity are assumed to exponentially depend on depth and temperature, respectively, while the variations in thermodynamic properties (thermal expansivity and reference density) with depth are taken to be relevant for the super-Earths with 10 times the Earth's. From our experiments we identified a distinct regime of convecting flow patterns induced by the interplay between the adiabatic temperature change and the spatial variations in viscosity and thermal conductivity. That is, for the cases with strong temperature-dependent viscosity and depth-dependent thermal conductivity, a "deep stratosphere" of stable thermal stratification is formed at the base of the mantle, in addition to thick stagnant lids at their top surfaces. In the "deep stratosphere", the fluid motion is insignificant particularly in the vertical direction in spite of smallest viscosity owing to its strong dependence on temperature. Our finding may further imply that some of super-Earths which are lacking in mobile tectonic plates on their top surfaces may have "deep stratospheres" at the base of their mantles.

  18. Mechanical and thermal design of an experiment aboard the space shuttle: the Spacelab spectrometer

    International Nuclear Information System (INIS)

    Besson, J.

    1985-01-01

    The spectrometer designed by ONERA and IASB (Belgium Space Aeronomy Institute) to measure atmospheric trace constituents was flown aboard Spacelab 1 during the 9 th mission of the American Space Shuttle from November 28 to December 8, 1983. After a brief summary of the history of the project related to Spacelab, the mechanical and thermal design of the spectrometer is described. Some methods, calculations and characteristic tests are detailed as examples. The behaviour of the experiment during the mission and the results of the post-flight tests are shortly analyzed in order to prepare the qualification for a reflight [fr

  19. Study of the thermal and suprathermal electron density fluctuations of the plasma in the Focus experiment

    International Nuclear Information System (INIS)

    Jolas, A.

    1981-10-01

    An experiment on Thomson scattering of ruby laser light by the electrons of a plasma produced by an intense discharge between the electrodes of a coaxial gun in a gas at low pressure has been carried out. It is shown that the imploding plasma is made up of layers with different characteristics: a dense plasma layer where the density fluctuations are isotropic and have a thermal level, and a tenuous plasma layer where the fluctuations are anisotropic, and strongly suprathermal. The suprathermal fluctuations are attributed to microscopic instabilities generated by the electric current circulating in the transition zone where the magnetic field penetrates the plasma [fr

  20. Review of the Thermal-Chemical Experiments for CANDU Fuel Channel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Tae; Min, Byung Joo; Park, Joo Hwan; Yoon, Churl; Rhee, Bo Wook

    2005-08-15

    In the present study, thermal-chemical experiments for CANDU channel analysis are reviewed. First, 11 experiments are identified from the present references and classified according to the number of heater rods, channel orientation, and degree of FES (Fuel Element Simulator) temperature rise during transient. The main configuration of the test rigs and the position of the measurement systems are identified. The experiments were generally conducted in three stages, a low-power, a high-power and a no-power stage. These test procedures are classified and described in this document. The experimental conditions for steam, coolant, and heat power are identified. The thermal properties of solid materials and fluids in the test apparatus are listed in the tables. From the review of the main test results, the following conclusions are to be obtained. Some of the reviewed experiments were not in the quasy-steady state conditions at a low-power stage and followed by a high-power stage. Zircaloy/steam reaction started when FES temperature were 800 .deg. C and escalated when temperature exceeded 1150 .deg. C. Uncontrolled temperature escalations due to Zircaloy/steam reaction were not observed when the FES temperature reached peak point (just below the melting point) and electric power to the test section shut off (self-sustaining Zircaloy/steam reaction). There were negligible circumferential temperature gradients in the FES bundle and pressure tube for the experiments performed in a vertical channel orientation. There were, however, noticeable circumferential gradients when the pressure tube was horizontal. These gradients were attributed to slumping of the FES bundle (sagging). Sagging of the bundle may have masked any buoyancy induced temperature gradients. Furthermore, the hot FES sagged towards the pressure tube transferring more heat to the pressure tube and increasing the temperature of the pressure tube.

  1. Review of the Thermal-Chemical Experiments for CANDU Fuel Channel

    International Nuclear Information System (INIS)

    Kim, Hyoung Tae; Min, Byung Joo; Park, Joo Hwan; Yoon, Churl; Rhee, Bo Wook

    2005-08-01

    In the present study, thermal-chemical experiments for CANDU channel analysis are reviewed. First, 11 experiments are identified from the present references and classified according to the number of heater rods, channel orientation, and degree of FES (Fuel Element Simulator) temperature rise during transient. The main configuration of the test rigs and the position of the measurement systems are identified. The experiments were generally conducted in three stages, a low-power, a high-power and a no-power stage. These test procedures are classified and described in this document. The experimental conditions for steam, coolant, and heat power are identified. The thermal properties of solid materials and fluids in the test apparatus are listed in the tables. From the review of the main test results, the following conclusions are to be obtained. Some of the reviewed experiments were not in the quasy-steady state conditions at a low-power stage and followed by a high-power stage. Zircaloy/steam reaction started when FES temperature were 800 .deg. C and escalated when temperature exceeded 1150 .deg. C. Uncontrolled temperature escalations due to Zircaloy/steam reaction were not observed when the FES temperature reached peak point (just below the melting point) and electric power to the test section shut off (self-sustaining Zircaloy/steam reaction). There were negligible circumferential temperature gradients in the FES bundle and pressure tube for the experiments performed in a vertical channel orientation. There were, however, noticeable circumferential gradients when the pressure tube was horizontal. These gradients were attributed to slumping of the FES bundle (sagging). Sagging of the bundle may have masked any buoyancy induced temperature gradients. Furthermore, the hot FES sagged towards the pressure tube transferring more heat to the pressure tube and increasing the temperature of the pressure tube

  2. Recent experimental progress in the TMX-U thermal barrier tandem mirror experiment

    International Nuclear Information System (INIS)

    Turner, W.C.; Allen, S.L.; Casper, T.A.

    1984-01-01

    Recent experiments on the TMX-U thermal barrier device at LLNL have achieved the end plugging of axial ion losses up to a central cell density of n/sub c/ = 2 x 10 12 cm. During these tests, the axial potential profile characteristic of a thermal barrier has been measured experimentally, indicating an ion-confining potential greater than 1.5 kV and a potential depression of 0.45 kV in the barrier region. The average beta of hot electrons in the thermal barrier has been increased to 15% and appears limited only by classical scattering and ECRH pulse duration. Furthermore, deuterium ions in the central cell have been heated with ICRF to an average energy of 1.5 keV, with a heating efficiency of 40%. During strong end plugging, the axial ion confinement time reached 50 to 100 ms while the nonambipolar radial ion confinement time was 5 to 15 ms - independent of end plugging. Radial ion confinement time exceeding 100 ms has been attained on shots without end plugging. Plates, floated electrically on the end walls, have increased the radial ion confinement time by a factor of 1.8. Further improvement in the central cell density during end plugging can be expected by increasing the ICRF, improving the central cell vacuum conditions and beam heating efficiency, and increasing the radial extent of the potential control plates on the end walls

  3. 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.

  4. Specific experiments carried out in Germany in order to demonstrate the safety of existing structures

    International Nuclear Information System (INIS)

    Krutzik, Norbert

    2002-01-01

    Specific experiments are carried out in Germany in order to demonstrate the safety of existing NPPs. HDR research program includes operational loads testing (pressure test, pressure and temperature test, thermal shock, fatigue); extreme loads (earthquake, aircraft crash, external explosion); internal emergency loads (blowdown, hydrogen combustion, fire, thermal shock, water hammer, condensation loads)

  5. Simulation and experiment on the thermal performance of U-vertical ground coupled heat exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinguo; Chen, Zhihao; Zhao, Jun [Department of Thermal Engineering, School of Mechanical Engineering, Tianjin University, Tianjin 300072 (China)

    2006-10-15

    This paper presented both the numerical simulations and experiments on the thermal performance of U-vertical ground coupled heat exchanger (UGCHE). The variation of the ground temperature and heat balance of the system were analyzed and compared in different operation modes in the numerical simulation. Experiments on the operation performance of the ground-coupled heat pump (GCHP) with the UGCHE were carried out. It shows that the ground source can be used as the heat source/sink for GCHP systems to have higher efficiency in saving energy. To preserve the ground resource for the sustainable utilization as heat source/sink, the heat emitted to ground and heat extracted from ground should be balanced. (author)

  6. A review of steam explosions with special emphasis on the Swedish and Finnish BWRs. APRI 4, Phase 2 Report

    Energy Technology Data Exchange (ETDEWEB)

    Sehgal, B.R.; Haraldsson, H.O.; Yang, Z.L. [Sehgal Konsult, Stockholm (Sweden)

    2002-04-01

    The objective of the present study is to perform a critical review of ex-vessel steam explosion in Swedish and Finnish reactor containments in a hypothetical severe accident. The review performed is related to a broader program funded by APRI whose focus is related to severe accidents. A critical review of the current knowledge base on the subject is performed, including those results obtained from other studies and assessments conducted earlier under auspice of APRI. Several limiting mechanisms which may significantly impact the assessment of steam explosion loads are identified, taking into account specific reactor-design features and accident progression scenarios. In addition, generic discussion is provided on the effect of melt physical properties on the steam explosion energetics. Thermal hydraulic conditions of pre-mixture and its explosivity are evaluated using models and methods developed by the researchers at Royal Institute of Technology (RIT). The report includes a wealth of information on details with respect to quantification of vessel melt sources for ex-vessel FCIs; and with respect to the models of steam explosion premixing, triggerability and explosivity employed in the present assessment. These and other models e.g. on vessel failure, melt jet fragmentation etc. are products of the continuing research conducted at the Division of Nuclear Power Safety at RIT. The general conclusion of the present study can be summarized as: Though substantial progress have been made in premixing research verifying the mixing limit concept, there is still a need to improve jet breakup models and validate the existing models against melt jet experiments. The understanding of the triggering mechanisms is still very pool. Though various analytical models have been developed based on the thermal detonation concepts, the need still exists in both experimental and analytical research to understand better the droplet fragmentation during the explosion or propagation phase

  7. A review of steam explosions with special emphasis on the Swedish and Finnish BWRs. APRI 4, Phase 2 Report

    International Nuclear Information System (INIS)

    Sehgal, B.R.; Haraldsson, H.O.; Yang, Z.L.

    2002-04-01

    The objective of the present study is to perform a critical review of ex-vessel steam explosion in Swedish and Finnish reactor containments in a hypothetical severe accident. The review performed is related to a broader program funded by APRI whose focus is related to severe accidents. A critical review of the current knowledge base on the subject is performed, including those results obtained from other studies and assessments conducted earlier under auspice of APRI. Several limiting mechanisms which may significantly impact the assessment of steam explosion loads are identified, taking into account specific reactor-design features and accident progression scenarios. In addition, generic discussion is provided on the effect of melt physical properties on the steam explosion energetics. Thermal hydraulic conditions of pre-mixture and its explosivity are evaluated using models and methods developed by the researchers at Royal Institute of Technology (RIT). The report includes a wealth of information on details with respect to quantification of vessel melt sources for ex-vessel FCIs; and with respect to the models of steam explosion premixing, triggerability and explosivity employed in the present assessment. These and other models e.g. on vessel failure, melt jet fragmentation etc. are products of the continuing research conducted at the Division of Nuclear Power Safety at RIT. The general conclusion of the present study can be summarized as: Though substantial progress have been made in premixing research verifying the mixing limit concept, there is still a need to improve jet breakup models and validate the existing models against melt jet experiments. The understanding of the triggering mechanisms is still very pool. Though various analytical models have been developed based on the thermal detonation concepts, the need still exists in both experimental and analytical research to understand better the droplet fragmentation during the explosion or propagation phase

  8. Pressurized-thermal-shock experiments: PTSE-1 results and PTSE-2 plans

    International Nuclear Information System (INIS)

    Bryan, R.H.; Nanstad, R.K.; Wanner, R.; Merkle, J.G.; Robinson, G.C.; Whitman, G.D.

    1985-01-01

    The first pressurized-thermal-shock experiment (PTSE-1) was performed with a vessel with a 1-m-long flaw in a plug of specially tempered steel having the composition of SA-508 forging steel. The second experiment (PTSE-2) will have a similar arrangement, but the material in which the flaw will be implanted is being prepared to have low tearing resistance. Special tempering of a 2 1/4 Cr - 1 Mo steel plate has been shown to induce a low Charpy impact energy in the upper-shelf temperature range. The purpose of PTSE-2 is to investigate the fracture behavior of low-upper-shelf material in a vessel under the combined loading of concurrent pressure and thermal shock. The primary objective of the experimental plan is to induce a rapidly propagating cleavage fracture under conditions that are likely to induce a ductile tearing instability at the time of arrest of the cleavage fracture. The secondary objective of the test is to extend the range of the investigation of warm prestressing. 11 figs

  9. Thermal barrier confinement experiments in TMX-U tandem mirror. Revision 1

    International Nuclear Information System (INIS)

    Simonen, T.C.; Allen, S.L.; Baldwin, D.E.

    1984-01-01

    In our recent experiments on the TMX-U thermal-barrier device, we achieved the end plugging of axial ion losses up to a central cell density of n/sub c/ = 6 x 10 12 cm -3 . During lower density experiments, we measured the axial potential profile characteristic of a thermal barrier and found an ion-confining potential greater than 1.5 kV and a potential depression of 0.45 kV in the barrier region. The average beta of hot end plug electrons has reached 15% and of hot central cell ions has reached 6%. In addition, we heated deuterium ions in the central cell with ICRF to an average perpendicular energy of 2 keV. During strong end plugging at low density (7 x 10 11 cm -3 ), the axial ion confinement time tau/sub parallel to/ reached 50 to 100 ms while the nonambiopolar radial ion confinement time tau/sub perpendicular to/ was 14 ms - independent of end plugging. Electrically floating end walls doubled the radial ion confinement time. At higher densities and lower potentials, tau/sub parallel to/ was 6 to 12 ms and tau/sub perpendicular to/ exceeded 100 ms

  10. BOW SHOCK FRAGMENTATION DRIVEN BY A THERMAL INSTABILITY IN LABORATORY ASTROPHYSICS EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki-Vidal, F.; Lebedev, S. V.; Pickworth, L. A.; Swadling, G. F.; Skidmore, J.; Hall, G. N.; Bennett, M.; Bland, S. N.; Burdiak, G.; De Grouchy, P.; Music, J.; Suttle, L. [Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW (United Kingdom); Ciardi, A. [Sorbonne Universités, UPMC Univ. Paris 6, UMR 8112, LERMA, F-75005, Paris (France); Rodriguez, R.; Gil, J. M.; Espinosa, G. [Departamento de Fisica de la Universidad de Las Palmas de Gran Canaria, E-35017 Las Palmas de Gran Canaria (Spain); Hartigan, P. [Department of Physics and Astronomy, Rice University, 6100 S. Main, Houston, TX 77521-1892 (United States); Hansen, E.; Frank, A., E-mail: f.suzuki@imperial.ac.uk [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States)

    2015-12-20

    The role of radiative cooling during the evolution of a bow shock was studied in laboratory-astrophysics experiments that are scalable to bow shocks present in jets from young stellar objects. The laboratory bow shock is formed during the collision of two counterstreaming, supersonic plasma jets produced by an opposing pair of radial foil Z-pinches driven by the current pulse from the MAGPIE pulsed-power generator. The jets have different flow velocities in the laboratory frame, and the experiments are driven over many times the characteristic cooling timescale. The initially smooth bow shock rapidly develops small-scale nonuniformities over temporal and spatial scales that are consistent with a thermal instability triggered by strong radiative cooling in the shock. The growth of these perturbations eventually results in a global fragmentation of the bow shock front. The formation of a thermal instability is supported by analysis of the plasma cooling function calculated for the experimental conditions with the radiative packages ABAKO/RAPCAL.

  11. Behaviour of the Callovo-Oxfordian clay around a converging heated borehole: thermal free wall experiment

    International Nuclear Information System (INIS)

    Garitte, B.; Gens, A.; Vaunat, J.; Armand, G.; Conil, N.

    2012-01-01

    Document available in extended abstract form only. ANDRA has launched several heating experiments in the Meuse-Haute Marne Underground Laboratory (e.g. TER and TED). In these experiments, the heater-rock contact was ensured by a metal tubing that prevented any convergence of the heating borehole. The Thermal Free Wall experiment was run by ANDRA to investigate whether the rock behaviour around an un-cased borehole was similar as in the previous experiments. Additionally, the temperature increase in the TFW was applied faster than in the previous experiments in order to investigate the rock response to a heavier thermal load. It consists in a main borehole containing the heater and two instrumentation boreholes equipped with a temperature and a pore water pressure sensor each. The sensors installed in borehole TER1906 are at approximately 40 cm from the heater borehole wall in the bedding plane. The TER1907 sensors are in the direction perpendicular to the bedding planes at about 70 cm from the heater borehole. The boreholes were drilled from the GEX gallery in the direction of the major in situ stress (16 MPa). The heater has an effective heating length of 3.29 m and is located between 7 and 10 m from the GEX gallery. It was emplaced on a base to centre it in the borehole and to have a void between the heater and the rock mass for free convergence. Heating started on 10 January 2011 and lasted 56 days. One of the requirements of the experiment was to apply a relatively fast heating ramp in comparison with the previous tests in order to investigate the rock behaviour under stronger thermal load. The increase from 21 C to 90 C at the external heater wall was achieved in 14 hours. The initial pore water pressure is about 3.2 MPa, somewhat lower than the undisturbed pore water pressure at the level of the laboratory (4.5 MPa). This difference is attributed to the presence of the GEX gallery that was excavated in July-September 2005. In this work, we present the

  12. 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.

  13. 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}.

  14. 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.

  15. 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.

  16. 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 ...

  17. 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 ...

  18. 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...

  19. 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

  20. 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.

  1. 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.

  2. 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)

  3. 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)

  4. 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.

  5. 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.

  6. 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)

  7. 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

  8. 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

  9. IRPhE/RRR-SEG, Reactor Physics Experiments from Fast-Thermal Coupled Facility

    International Nuclear Information System (INIS)

    Weiss, Frank-Peter; Dietze, Klaus; Jacqmin, Robert; Ishikawa, Makoto

    2003-01-01

    1 - Description: The RRR-SEG-experiments have been performed to check neutron data of the most important reactor materials, especially of fission product nuclides, fuel isotopes and structural materials. The measured central reactivity worths (CRW) of small samples were compared with calculated values. These C/E-ratios have been used then for data corrections or in adjustment procedures. The reactor RRG-SEG (at RC Rossendorf / Germany) was a fast-thermal coupled facility of zero power. The annular thermal drivers were filled by fuel assemblies and moderated by water. The inner insertion lattices were loaded with pellets of fuel and other materials producing the fast neutron flux. The characteristics of the neutron and adjoint spectra were obtained by special arrangements of these pellets in unit cells. In this way, a hard or soft neutron spectrum or a special energy behavior of the adjoint function could be reached. The samples were moved by means of tubes to the central position (pile-oscillation technique). The original information about the facility and measurements is compiled in Note Technique SPRC/LEPh/93-230 (SEG) The SEG experiments are considered 'clean' integral experiments, simple and clear in geometry and well suited for calculation. In all SEG configurations only a few materials were used, most of these were standards. Due to the designed adjoint function (energy-independent or monotonously rising), the capture or scattering effect was dominant, convenient to check separately capture or scattering data. At first, analyses of the experiments have been performed in Rossendorf. Newer analyses were done later in Cadarache / CEA France using the European scheme for reactor calculation JEF-2.2 / ECCO / ERANOS (see Note Techniques and JEF/DOC-746). Furthermore, re-analyses were performed in O-arai / JNC Japan with the JNC standard route JENDL-3.2 / SLAROM / CITATION / PERKY. Results obtained with both code systems and different data evaluations (JEF-2.2 and

  10. Initial Scaling Studies and Conceptual Thermal Fluids Experiments for the Prismatic NGNP Point Design

    Energy Technology Data Exchange (ETDEWEB)

    D. M. McEligot; G. E. McCreery

    2004-09-01

    The objective of this report is to document the initial high temperature gas reactor scaling studies and conceptual experiment design for gas flow and heat transfer. The general approach of the project is to develop new benchmark experiments for assessment in parallel with CFD and coupled CFD/ATHENA/RELAP5-3D calculations for the same geometry. Two aspects of the complex flow in an NGNP are being addressed: (1) flow and thermal mixing in the lower plenum ("hot streaking" issue) and (2) turbulence and resulting temperature distributions in reactor cooling channels ("hot channel" issue). Current prismatic NGNP concepts are being examined to identify their proposed flow conditions and geometries over the range from normal operation to decay heat removal in a pressurized cooldown. Approximate analyses are being applied to determine key non-dimensional parameters and their magnitudes over this operating range. For normal operation, the flow in the coolant channels can be considered to be dominant forced convection with slight transverse property variation. The flow in the lower plenum can locally be considered to be a situation of multiple buoyant jets into a confined density-stratified crossflow -- with obstructions. Experiments are needed for the combined features of the lower plenum flows. Missing from the typical jet experiments are interactions with nearby circular posts and with vertical posts in the vicinity of vertical walls - with near stagnant surroundings at one extreme and significant crossflow at the other. Two heat transfer experiments are being considered. One addresses the "hot channel" problem, if necessary. The second experiment will treat heated jets entering a model plenum. Unheated MIR (Matched-Index-of-Refraction) experiments are first steps when the geometry is complicated. One does not want to use a computational technique which will not even handle constant properties properly. The MIR experiment will simulate flow features of the paths of jets

  11. Investigation of the shallow depth explosions

    International Nuclear Information System (INIS)

    Kamegai, M.

    1976-01-01

    An investigation of the nuclear explosions at shallow depth is made. A combination of an explosion code and an effects code proves to be an excellent tool for this study. A numerical simulation of ''Johnie Boy'' shows that the energy coupling to the air takes place in two stages; first by a rising mound, and then by a vented source. The thermal effects are examined for a 1 kt source at three depths of burial. The ''mushroom effect'' leaves a hot radiative plasma in the upper level and cold materials in the lower region of the debris. The temperature and the energy density of the debris can give an upper limit on the thermal output

  12. Characteristics of a plasma flow field produced by a metal array bridge foil explosion

    Science.gov (United States)

    Junying, WU; Long, WANG; Yase, LI; Lijun, YANG; Manzoor, SULTAN; Lang, CHEN

    2018-07-01

    To improve the energy utilization efficiency of metal bridge foil explosion, and increase the function range of plasmas, array bridge foil explosion experiments with different structures were performed. A Schlieren photographic measurement system with a double-pulse laser source was used to observe the flow field of a bridge foil explosion. The evolution laws of plasmas and shock waves generated by array bridge foil explosions of different structures were analyzed and compared. A multi-phase flow calculation model was established to simulate the electrical exploding process of a metal bridge foil. The plasma equation of state was determined by considering the effect of the changing number of particles and Coulomb interaction on the pressure and internal energy. The ionization degree of the plasma was calculated via the Saha–Eggert equation assuming conditions of local thermal equilibrium. The exploding process of array bridge foils was simulated, and the superposition processes of plasma beams were analyzed. The variation and distribution laws of the density, temperature, pressure, and other important parameters were obtained. The results show that the array bridge foil has a larger plasma jet diameter than the single bridge foil for an equal total area of the bridge foil. We also found that the temperature, pressure, and density of the plasma jet’s center region sharply increase because of the superposition of plasma beams.

  13. Centralized vs. decentralized thermal IR inspection policy: experience from a major Brazilian electric power company

    Science.gov (United States)

    dos Santos, Laerte; da Costa Bortoni, Edson; Barbosa, Luiz C.; Araujo, Reyler A.

    2005-03-01

    Furnas Centrais Elétricas S.A is one of the greatest companies of the Brazilian electric power sector and a pioneer in using infrared thermography. In the early 70s, the maintenance policy used was a centralized approach, with only one inspection team to cover all the company"s facilities. In the early 90s, FURNAS decided to decentralize the thermography inspections creating several inspection teams. This new maintenance policy presented several advantages when compared to the previous one. However the credibility of the results obtained with the thermal inspection was frequently being questioned, in part due to the lack of a detailed planning to carry out the transition from the centralized inspection to the decentralized one. In some areas of the company it was suggested the inactivation of the thermography. This paper presents the experience of FURNAS with these different maintenance policies and details the procedures which have been taken that nowadays the infrared thermal inspection has become one of the most important techniques of predictive maintenance in the company.

  14. The NEPTUN experiments on LOCA thermal-hydraulics for tight-lattice PWRs

    International Nuclear Information System (INIS)

    Dreier, J.; Chawla, R.; Rouge, N.; Yanar, S.

    1990-01-01

    The NEPTUN test facility at the Paul Scherrer Institute is currently being used to provide a broad data base for the validation of thermal-hydraulics codes used in predicting the reflooding behaviour of a tight-lattice PWR (light water highb conversion reactor, LWHCR). The present paper gives a description of the facility and the matrix to be covered in the experimental program. Results are presented from a number of forced-feed, bottom-reflooding experiments, comparisons being made with (a) measurements carried out earlier for standard-PWR geometry and (b) the results of a calculational benchmark exercise conducted in the framework of a Swiss/German LWHCR-development agreement. Rewetting for the tight, hexagonal-geometry (p/d = 1.13) NEPTUN-III test bundle has been found to occur in all tests carried out to date, in which reasonably LWHCR-representative values for the various thermal-hydraulics parameters are used. Results of the calculational benchmark exercise have confirmed the need for further code development efforts for achieving reliable predictions of LWHCR reflooding behaviour. (author) 11 figs., 3 tabs., 3 refs

  15. Thermal analysis to support decommissioning of the molten salt reactor experiment

    International Nuclear Information System (INIS)

    Sulfredge, C.D.; Morris, D.G.; Park, J.E.; Williams, P.T.

    1996-06-01

    As part of the decommissioning process for the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory, several thermal-sciences issues were addressed. Apparently a mixture of UF 6 and F 2 had diffused into the upper portion of one charcoal column in the MSRE auxiliary charcoal bed (ACB), leading to radiative decay heating and possible chemical reaction sources. A proposed interim corrective action was planned to remove the water from the ACB cell to reduce criticality and reactivity concerns and then fill the ACB cell with an inert material. This report describes design of a thermocouple probe to obtain temperature measurements for mapping the uranium deposit, as well as development of steady-state and transient numerical models for the heat transfer inside the charcoal column. Additional numerical modeling was done to support filling of the ACB cell. Results from this work were used to develop procedures for meeting the goals of the MSRE Remediation Project without exceeding appropriate thermal limits

  16. [Gradient elevation of temperature startup experiment of thermophilic ASBR treating thermal-hydrolyzed sewage sludge].

    Science.gov (United States)

    Ouyang, Er-Ming; Wang, Wei; Long, Neng; Li, Huai

    2009-04-15

    Startup experiment was conducted for thermophilic anaerobic sequencing batch reactor (ASBR) treating thermal-hydrolyzed sewage sludge using the strategy of the step-wise temperature increment: 35 degrees C-->40 degrees C-->47 degrees C-->53 degrees C. The results showed that the first step-increase (from 35 degrees C to 40 degrees C) and final step-increase (from 47 degrees C to 53 degrees C) had only a slight effect on the digestion process. The second step-increase (from 40 degrees C to 47 degrees C) resulted in a severe disturbance: the biogas production, methane content, CODeffluent and microorganism all have strong disturbance. At the steady stage of thermophilic ASBR treating thermal-hydrolyzed sewage sludge, the average daily gas production, methane content, specific methane production (CH4/CODinfluent), TCOD removal rate and SCOD removal rate were 2.038 L/d, 72.0%, 188.8 mL/g, 63.8%, 83.3% respectively. The results of SEM and DGGE indicated that the dominant species are obviously different at early stage and steady stage.

  17. Thermal analysis to support decommissioning of the molten salt reactor experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sulfredge, C.D.; Morris, D.G.; Park, J.E.; Williams, P.T.

    1996-06-01

    As part of the decommissioning process for the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory, several thermal-sciences issues were addressed. Apparently a mixture of UF{sub 6} and F{sub 2} had diffused into the upper portion of one charcoal column in the MSRE auxiliary charcoal bed (ACB), leading to radiative decay heating and possible chemical reaction sources. A proposed interim corrective action was planned to remove the water from the ACB cell to reduce criticality and reactivity concerns and then fill the ACB cell with an inert material. This report describes design of a thermocouple probe to obtain temperature measurements for mapping the uranium deposit, as well as development of steady-state and transient numerical models for the heat transfer inside the charcoal column. Additional numerical modeling was done to support filling of the ACB cell. Results from this work were used to develop procedures for meeting the goals of the MSRE Remediation Project without exceeding appropriate thermal limits.

  18. Field Experiments of PV-Thermal Collectors for Residential Application in Bangkok

    Directory of Open Access Journals (Sweden)

    Atsushi Akisawa

    2012-04-01

    Full Text Available This study presents experimental results on Photovoltaic-thermal (PVT solar systems, the commercial photovoltaic (PV panels used as solar absorbers in PVT collectors, which are amorphous and multi-crystalline silicon. Testing was done with outdoor experiments in the climate of Bangkok corresponding to energy consumption behavior of medium size Thai families. The experimental results show that the thermal recovery of amorphous silicon PVT collector is almost the same as that of multi-crystalline silicon PVT collectors while electricity generation of multi crystalline silicon PVT is 1.2 times as much as that of amorphous silicon PVT. The maximum of heat gain from the PVT systems were obtained in March in summer. It was found that PVT collectors of unit area annually produced 1.1 × 103 kWh/m2 .year of heat and 55–83 kWh/m2.year of electricity, respectively. The results show that annual average solar factor of hot water supply is 0.45 for unit collector area. Economical evaluation based on energy costs in Thailand was conducted, which estimated the payback time would be 7 and 14 years for a-Si PVT and mc-Si PV, respectively.

  19. Designing experiments on thermal interactions by secondary-school students in a simulated laboratory environment

    Science.gov (United States)

    Lefkos, Ioannis; Psillos, Dimitris; Hatzikraniotis, Euripides

    2011-07-01

    Background and purpose: The aim of this study was to explore the effect of investigative activities with manipulations in a virtual laboratory on students' ability to design experiments. Sample Fourteen students in a lower secondary school in Greece attended a teaching sequence on thermal phenomena based on the use of information and communication technology, and specifically of the simulated virtual laboratory 'ThermoLab'. Design and methods A pre-post comparison was applied. Students' design of experiments was rated in eight dimensions; namely, hypothesis forming and verification, selection of variables, initial conditions, device settings, materials and devices used, process and phenomena description. A three-level ranking scheme was employed for the evaluation of students' answers in each dimension. Results A Wilcoxon signed-rank test revealed a statistically significant difference between the students' pre- and post-test scores. Additional analysis by comparing the pre- and post-test scores using the Hake gain showed high gains in all but one dimension, which suggests that this improvement was almost inclusive. Conclusions We consider that our findings support the statement that there was an improvement in students' ability to design experiments.

  20. Thermal neutron absorption cross-section for small samples (experiments in cylindrical geometry)

    International Nuclear Information System (INIS)

    Czubek, J.A.; Drozdowicz, K.; Igielski, A.; Krynicka-Drozdowicz, E.; Woznicka, U.

    1982-01-01

    Measurement results for thermal neutron macroscopic absorption cross-sections Σsub(a)1 when applying the cylindrical sample-moderator system are presented. Experiments for liquid (water solutions of H 3 BO 3 ) and solid (crushed basalts) samples are reported. Solid samples have been saturated with the H 3 BO 3 ''poisoning'' solution. The accuracy obtained for the determination of the absorption cross-section of the solid material was σ(Σsub(ma))=(1.2+2.2) c.u. in the case when porosity was measured with the accuracy of σ(phi)=0.001+0.002. The dispersion of the Σsub(ma) data obtained for basalts (taken from different quarries) was higher than the accuracy of the measurement. All experimental data for the fundamental decay constants lambda 0 together with the whole information about the samples are given. (author)

  1. Analysis of crack behavior in the JRC Ispra pressurized thermal shock experiment

    International Nuclear Information System (INIS)

    Jovanovic, A.; Lucia, A.C.

    1990-01-01

    The analytical work performed in the framework of the Pressurized Thermal Shock (PTS) experimental research at the JRC Ispra, Italy, is described in the paper. In particular, the development of the FRAP preprocessor and development and implementation of a methodology for analysis of local non-stationary heat transfer coefficients during a PTS, have been tackled. FRAP is used as a front-end for the finite element code ABAQUS, for the heat transfer, stress and fracture mechanics analyses. The ABAQUS results are used further on, for the probabilistic fatigue crack analysis performed by the JRC Ispra code COVASTOL. Only the preliminary results of application of FRAP, ABAQUS and COVASTOL codes in the experiment are given in this paper, in order to illustrate the applied analytical procedure. (orig.)

  2. Experiments and analyses in support of the US ALMR thermal-hydraulic design

    International Nuclear Information System (INIS)

    Hunsbedt, A.

    1993-01-01

    The U.S. Advanced Liquid Metal Reactor (ALMR) which is based on the modular PRISM concept utilizes passive safety characteristics to simplify the reactor design and enhance its safety performance. The relatively small size of each reactor facilitates the use of strong negative feedback with rising temperature for inherent reactivity control and direct, natural air cooling for decay heat removal. The tall, slender reactor geometry of the ALMR enhances uniformity and stability of internal flow distribution during steady state operation and natural circulation flow during transient conditions. The flow uniformity and low operating pressure and temperature of the reactor contributes to high structural margins. A number of experiments and associated analyses have been performed to evaluate natural convection and thermal-hydraulic phenomena experienced under decay heat removal conditions. This paper summarizes these various efforts as described separately below and presents the main results. (author)

  3. Surface energy of explosive nanoparticles

    Science.gov (United States)

    Pineau, Nicolas; Bidault, Xavier; Soulard, Laurent

    2017-06-01

    Recent experimental studies show that nanostructuration has a substantial impact on the detonation of high explosives: a nanostructured one leads to smaller nanodiamonds than a microstructured one. Whether it comes from a higher surface energy or from porosity, the origin of these different behaviors must be investigated. The surface energy of TATB nanoparticles with a radius from 2 nm upto 60 nm has been determined by means of ReaxFF-based simulations. Then, using the Rankine-Hugoniot relations and the equation of states of the bulk material, the contribution of this excess energy to the heating of a shock-compressed nanostructured (and porous) material is evaluated and compared to the thermal effect due to its porosity collapse. A maximum temperature increase of 50 K is found for 4-nm nanoparticles, which remains negligible when compared to the few hundred degrees induced by the compaction work.

  4. Three-dimensional coupled kinetics/thermal- hydraulic benchmark TRIGA experiments

    International Nuclear Information System (INIS)

    Feltus, Madeline Anne; Miller, William Scott

    2000-01-01

    This research project provides separate effects tests in order to benchmark neutron kinetics models coupled with thermal-hydraulic (T/H) models used in best-estimate codes such as the Nuclear Regulatory Commission's (NRC) RELAP and TRAC code series and industrial codes such as RETRAN. Before this research project was initiated, no adequate experimental data existed for reactivity initiated transients that could be used to assess coupled three-dimensional (3D) kinetics and 3D T/H codes which have been, or are being developed around the world. Using various Test Reactor Isotope General Atomic (TRIGA) reactor core configurations at the Penn State Breazeale Reactor (PSBR), it is possible to determine the level of neutronics modeling required to describe kinetics and T/H feedback interactions. This research demonstrates that the small compact PSBR TRIGA core does not necessarily behave as a point kinetics reactor, but that this TRIGA can provide actual test results for 3D kinetics code benchmark efforts. This research focused on developing in-reactor tests that exhibited 3D neutronics effects coupled with 3D T/H feedback. A variety of pulses were used to evaluate the level of kinetics modeling needed for prompt temperature feedback in the fuel. Ramps and square waves were used to evaluate the detail of modeling needed for the delayed T/H feedback of the coolant. A stepped ramp was performed to evaluate and verify the derived thermal constants for the specific PSBR TRIGA core loading pattern. As part of the analytical benchmark research, the STAR 3D kinetics code (, STAR: Space and time analysis of reactors, Version 5, Level 3, Users Guide, Yankee Atomic Electric Company, YEAC 1758, Bolton, MA) was used to model the transient experiments. The STAR models were coupled with the one-dimensional (1D) WIGL and LRA and 3D COBRA (, COBRA IIIC: A digital computer program for steady-state and transient thermal-hydraulic analysis of rod bundle nuclear fuel elements, Battelle

  5. 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

  6. 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

  7. 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)

  8. IRPhE/STEK, Reactor Physics Experiments from Fast-Thermal Coupled Facility

    International Nuclear Information System (INIS)

    Dietze, Klaus; Klippel, Henk Th.; Koning, Arjan; Jacqmin, Robert

    2003-01-01

    1 - Description: The STEK-experiments have been performed to check neutron data of the most important reactor materials, especially of fission product nuclides, fuel isotopes and structural materials. The measured central reactivity worths (CRW) of small samples were compared with calculated values. These C/E-ratios have been used then for data corrections or in adjustment procedures. The reactors STEK (ECN Petten/ Netherlands) was a fast-thermal coupled facility of zero power. The annular thermal drivers were filled by fuel assemblies and moderated by water. The inner insertion lattices were loaded with pellets of fuel and other materials producing the fast neutron flux. The characteristics of the neutron and adjoint spectra were obtained by special arrangements of these pellets in unit cells. In this way, a hard or soft neutron spectrum or a special energy behavior of the adjoint function could be reached. The samples were moved by means of tubes to the central position (pile-oscillation technique). The original information about the facility and measurements is compiled in RCN-209, ECN-10 The 5 STEK configurations cover a broad energy range due to their increasing softness. The experiments are very valuable because of the extensive program of sample reactivity measurements with many fission product nuclides important in reactor burn-up calculations. At first, analyses of the experiments have been performed in Petten. Newer analyses were done later in Cadarache / CEA France using the European scheme for reactor calculation JEF-2.2 / ECCO / ERANOS (see Note Techniques and JEF/DOC-746). Furthermore, re-analyses were performed in O-arai / JNC Japan with the JNC standard route JENDL-3.2 / SLAROM / CITATION / PERKY. Results obtained with both code systems and different data evaluations (JEF-2.2 and JENDL-3.2) are compared in JEF/DOC-861. It contains the following documents: 31 Reports, 2 publications, 5 JEF documents, 4 conferences. 2 - Related or auxiliary programs

  9. Gas pressure from a nuclear explosion in oil shale

    International Nuclear Information System (INIS)

    Taylor, R.W.

    1975-01-01

    The quantity of gas and the gas pressure resulting from a nuclear explosion in oil shale is estimated. These estimates are based on the thermal history of the rock during and after the explosion and the amount of gas that oil shale releases when heated. It is estimated that for oil shale containing less than a few percent of kerogen the gas pressure will be lower than the hydrostatic pressure. A field program to determine the effects of nuclear explosions in rocks that simulate the unique features of oil shale is recommended. (U.S.)

  10. 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)

  11. Radioactive and Other Effects of Nuclear Explosion

    International Nuclear Information System (INIS)

    Ilijas, B.; Cizmek, A.; Prah, M.; Medakovic, S.

    2008-01-01

    As a result of long lasting efforts of international community to definitely ban all test nuclear explosions, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was opened for signature in New York on 24 September 1996, when it was signed by 71 states, including Croatia. The State Office for Nuclear Safety (SONS) which, as an independent state regulatory authority has a responsibility for activities relating to nuclear safety, including the national authority over this Treaty, is actively engaged in CTBTO activities. The nuclear explosion causes a lot of effects (blast, thermal, radioactive, electromagnetic) which differs a lot in its nature, reach, lasting and other. The longest lasting aftermath is from the radioactive effects that cause a radioactive fallout and a lot of radioactive elements in the environment, created by the influence of a primary beam of radiation. Fission and fusion are the main source of radionuclide created by the nuclear explosion, and the longest lasting aftermaths are by the fission products, namely their offspring in natural disintegration chains. This can make contaminated areas inappropriate for life for very long periods. Even in the case of underground nuclear explosion (when underground cavity is formed with no effects on the surface), a leakage of radioactive gases through cracks is possible. A number of radionuclide is created by the neutron activation of elements naturally present in an environment, because a very strong neutron radiation appears in the moment of nuclear explosion. The abundance of particular radionuclide is a very much dependent of a place of performing nuclear explosion and a composition of soil or water in the vicinity.(author)

  12. Comparison between the Findings from the TROI Experiments and the Sensitivity Studies by Using the TEXAS-V Code

    International Nuclear Information System (INIS)

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

    2006-01-01

    Since a steam explosion may breach the integrity of a reactor vessel and containment, it is one of the most important severe accident issues. So, a lot of experimental and analytical researches on steam explosions have been performed. Although many findings from the steam explosion researches have been obtained, there still exist unsolved issues such as the explosivity of the real core material(corium) and the conversion ratio from the thermal energy to the mechanical energy. TROI experiments were carried out to provide the experimental data for these issues. The TROI experiments were performed with a prototypic material such as ZrO 2 melt and a mixture of ZrO 2 and UO 2 melt (corium). Several steam explosion codes including TEXAS-V had been developed by considering the findings in the past steam explosion experiments. However, some unique findings on steam explosions have been obtained from a series of TROI experiments. These findings should be considered in the application to a reactor safety analysis by using a computational code. In this paper, several findings from TROI experiments are discussed and the sensitivity studies on the TROI experimental parameters were conducted by using TEXAS-V code and TROI-13 test. The comparison between the TROI experimental findings and the results of the sensitivity study might allow us to know which parameter is important and which model is uncertain for steam explosions

  13. Thermal-Hydraulic Experiment To Test The Stable Operation Of A PIUS Type Reactor

    International Nuclear Information System (INIS)

    Irianto, Djoko; Kanji, T.; Kukita, Y.

    1996-01-01

    An advanced type of reaktor concept as the Process Inherent Ultimate Safety (PIUS) reactor was based on intrinsically passive safety considerations. The stable operation of a PIUS type reactor is based on the automation of circulation pump speed. An automatic circulation pump speed control system by using a measurement of the temperature distribution in the lower density lock is proposed the PIUS-type reactor. In principle this control system maintains the fluid temperature at the axial center of the lower density lock at average of the fluid temperatures below and above the lower density lock. This control system will prevent the poison water from penetrating into the core during normal operation. The effectiveness of this control system was successfully confirmed by a series of experiments using atmospheric pressure thermal-hydraulic test loop which simulated the PIUS principle. The experiments such as: start-up and power ramping tests for normal operation simulation and loss of feedwater test for an accident condition simulation, carried out in JAERI

  14. Blowdown hydraulic influence on core thermal response in LOFT nuclear experiment L2-3

    International Nuclear Information System (INIS)

    Reeder, D.L.

    1979-01-01

    Experimental research into pressurized water reactor (PWR) loss-of-coolant phenomena conducted in the Loss-of-Fluid Test (LOFT) facility has given results indicating that for very large pipe breaks the core thermal response is tightly coupled to the fluid hydraulic phenomena during the blowdown phase of the loss-of-coolant transient. This summary presents and discusses data supporting this conclusion. LOFT Loss-of-Coolant Experiment (LOCE) L2-3 simulated a complete double-ended offset shear break of a primary coolant reactor vessel inlet pipe in a commercial PWR. The LOFT system conditions at experiment initiation were: fuel rod maximum linear heat generation rate (MLHGR) of 39.4 +- 3 kW/m, hot leg temperature of 593 +- 3 K, core ΔT of 32.2 +- 4 K, system pressure of 15.06 +- 0.03 MPa, and flow rate/system volume of 25.6 +- 0.8 kg/m 3 . These conditions are typical of those in commercial PWR systems at normal operating conditions

  15. DESIGN OF LABORATORY EXPERIMENTS TO STUDY PHOTOIONIZATION FRONTS DRIVEN BY THERMAL SOURCES

    International Nuclear Information System (INIS)

    Drake, R. P.; Keiter, P. A.; Davis, J. S.; Patterson, C. R; Hazak, G.; Frank, A.; Blackman, E. G.; Busquet, Michel

    2016-01-01

    This paper analyzes the requirements of a photoionization-front experiment that could be driven in the laboratory, using thermal sources to produce the necessary flux of ionizing photons. It reports several associated conclusions. Such experiments will need to employ the largest available facilities, capable of delivering many kJ to MJ of energy to an X-ray source. They will use this source to irradiate a volume of neutral gas, likely of N, on a scale of a few mm to a few cm, increasing with source energy. For a gas pressure of several to ten atmospheres at room temperature, and a source temperature near 100 eV, one will be able to drive a photoionization front through a system of tens to hundreds of photon mean free paths. The front should make the familiar transition from the so-called R-Type to D-Type as the radiation flux diminishes with distance. The N is likely to reach the He-like state. Preheating from the energetic photons appears unlikely to become large enough to alter the essential dynamics of the front beyond some layer near the surface. For well-chosen experimental conditions, competing energy transport mechanisms are small.

  16. Numerical experiment on variance biases and Monte Carlo neutronics analysis with thermal hydraulic feedback

    International Nuclear Information System (INIS)

    Hyung, Jin Shim; Beom, Seok Han; Chang, Hyo Kim

    2003-01-01

    Monte Carlo (MC) power method based on the fixed number of fission sites at the beginning of each cycle is known to cause biases in the variances of the k-eigenvalue (keff) and the fission reaction rate estimates. Because of the biases, the apparent variances of keff and the fission reaction rate estimates from a single MC run tend to be smaller or larger than the real variances of the corresponding quantities, depending on the degree of the inter-generational correlation of the sample. We demonstrate this through a numerical experiment involving 100 independent MC runs for the neutronics analysis of a 17 x 17 fuel assembly of a pressurized water reactor (PWR). We also demonstrate through the numerical experiment that Gelbard and Prael's batch method and Ueki et al's covariance estimation method enable one to estimate the approximate real variances of keff and the fission reaction rate estimates from a single MC run. We then show that the use of the approximate real variances from the two-bias predicting methods instead of the apparent variances provides an efficient MC power iteration scheme that is required in the MC neutronics analysis of a real system to determine the pin power distribution consistent with the thermal hydraulic (TH) conditions of individual pins of the system. (authors)

  17. DESIGN OF LABORATORY EXPERIMENTS TO STUDY PHOTOIONIZATION FRONTS DRIVEN BY THERMAL SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    Drake, R. P.; Keiter, P. A.; Davis, J. S.; Patterson, C. R [Climate and Space Science, University of Michigan, Ann Arbor, MI 48109 (United States); Hazak, G. [Physics Department, Nuclear Research Center-Negev (Israel); Frank, A.; Blackman, E. G. [Physics and Astronomy, University of Rochester, Rochester, NY 14611 (United States); Busquet, Michel, E-mail: rpdrake@umich.edu [ARTEP Incorporated, Ellicot City, MD 21042 (United States)

    2016-12-20

    This paper analyzes the requirements of a photoionization-front experiment that could be driven in the laboratory, using thermal sources to produce the necessary flux of ionizing photons. It reports several associated conclusions. Such experiments will need to employ the largest available facilities, capable of delivering many kJ to MJ of energy to an X-ray source. They will use this source to irradiate a volume of neutral gas, likely of N, on a scale of a few mm to a few cm, increasing with source energy. For a gas pressure of several to ten atmospheres at room temperature, and a source temperature near 100 eV, one will be able to drive a photoionization front through a system of tens to hundreds of photon mean free paths. The front should make the familiar transition from the so-called R-Type to D-Type as the radiation flux diminishes with distance. The N is likely to reach the He-like state. Preheating from the energetic photons appears unlikely to become large enough to alter the essential dynamics of the front beyond some layer near the surface. For well-chosen experimental conditions, competing energy transport mechanisms are small.

  18. Feeble magnetic fields generated by thermal charge fluctuations in extended metallic conductors: Implications for electric-dipole moment experiments

    International Nuclear Information System (INIS)

    Lamoreaux, S.K.

    1999-01-01

    A simple formulation for calculating the magnetic field external to an extended nonpermeable conducting body due to thermal current fluctuations within the body is developed, and is applied to a recent experimental search for the atomic electric-dipole moment (EDM) of 199 Hg. It is shown that the thermal fluctuation field is only slightly smaller in magnitude than other noise sources in that experiment. The formulation is extended to permeable bodies, and the implications for general EDM experiments are discussed. copyright 1999 The American Physical Society

  19. 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

  20. Experiments on intrinsic and thermally induced chaos in an rf-driven Josephson junction

    DEFF Research Database (Denmark)

    Davidson, A.; Dueholm, B.; Beasley, M. R.

    1986-01-01

    We report detailed measurements of low-frequency noise due to microwaves applied to a real Josephson tunnel junction. An intrinsically chaotic region is apparently identified, but the effects of thermal noise are shown to be significant. In particular we show experimental data that we interpret a...... as evidence for thermally activated hopping and thermally affected chaos. The data are only in qualitative accord with recent ideas regarding the effect of thermal noise on intermittent chaos....

  1. 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

  2. Space Shuttle Thermal Protection System Repair Flight Experiment Induced Contamination Impacts

    Science.gov (United States)

    Smith, Kendall A.; Soares, Carlos E.; Mikatarian, Ron; Schmidl, Danny; Campbell, Colin; Koontz, Steven; Engle, Michael; McCroskey, Doug; Garrett, Jeff

    2006-01-01

    NASA s activities to prepare for Flight LF1 (STS-114) included development of a method to repair the Thermal Protection System (TPS) of the Orbiter s leading edge should it be damaged during ascent by impacts from foam, ice, etc . Reinforced Carbon-Carbon (RCC) is used for the leading edge TPS. The repair material that was developed is named Non- Oxide Adhesive eXperimental (NOAX). NOAX is an uncured adhesive material that acts as an ablative repair material. NOAX completes curing during the Orbiter s descent. The Thermal Protection System (TPS) Detailed Test Objective 848 (DTO 848) performed on Flight LF1 (STS-114) characterized the working life, porosity void size in a micro-gravity environment, and the on-orbit performance of the repairs to pre-damaged samples. DTO 848 is also scheduled for Flight ULF1.1 (STS-121) for further characterization of NOAX on-orbit performance. Due to the high material outgassing rates of the NOAX material and concerns with contamination impacts to optically sensitive surfaces, ASTM E 1559 outgassing tests were performed to determine NOAX condensable outgassing rates as a function of time and temperature. Sensitive surfaces of concern include the Extravehicular Mobility Unit (EMU) visor, cameras, and other sensors in proximity to the experiment during the initial time after application. This paper discusses NOAX outgassing characteristics, how the amount of deposition on optically sensitive surfaces while the NOAX is being manipulated on the pre-damaged RCC samples was determined by analysis, and how flight rules were developed to protect those optically sensitive surfaces from excessive contamination where necessary.

  3. Evolutionary design of a satellite thermal control system: Real experiments for a CubeSat mission

    International Nuclear Information System (INIS)

    Escobar, Emanuel; Diaz, Marcos; Zagal, Juan Cristóbal

    2016-01-01

    Highlights: • GAs applied to automate design of CubeSat passive thermal control system (coating). • Simulation adapted with real physical data (mockup experiment in vacuum chamber). • Obtained coating patterns consistently outperform engineered solutions (by 5 K). • Evolved coating patterns are far superior (by 8 K) than unpainted aluminum. - Abstract: This paper studies the use of artificial evolution to automate the design of a satellite passive thermal control system. This type of adaptation often requires the use of computer simulations to evaluate fitness of a large number of candidate solutions. Simulations are required to be expedient and accurate so that solutions can be successfully transferred to reality. We explore a design process that involves three steps. On a first step candidate solutions (implemented as surface paint tiling patterns) are tested using a FEM model and ranked according to their quality to meet mission temperature requirements. On a second step the best individual is implemented as a real physical satellite mockup and tested inside a vacuum chamber, having light sources imitating the effect of solar light. On a third step the simulation model is adapted with data obtained during the real evaluation. These updated models can be further employed for continuing genetic search. Current differences between our simulation and our real physical setup are in the order of 1.45 K mean squared error for faces pointing toward the light source and 2.4 K mean squared errors for shadowed faces. We found that evolved tiling patterns can be 5 K below engineered patterns and 8 K below using unpainted aluminum satellite surfaces.

  4. 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...

  5. 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...

  6. 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...

  7. 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.

  8. Shock tube experiments on nitromethane and Promotion of chemical reactions by non-thermal plasma

    Energy Technology Data Exchange (ETDEWEB)

    Seljeskog, Morten

    2002-06-01

    This dissertation was undertaken to study two different subjects both related to molecular decomposition by applying a shock tube and non-thermal plasma to decompose selected hydrocarbons. The first approach to molecular decomposition concerned thermal decomposition and oxidation of highly diluted nitromethane (NM) in a shock tube. Reflected shock tube experiments on NM decomposition, using mixtures of 0.2 to 1.5 vol% NM in nitrogen or argon were performed over the temperature range 850-1550 K and pressure range 190-900 kPa, with 46 experiments diluted in nitrogen and 44 diluted in argon. By residual error analysis of the measured decomposition profiles it was found that NM decomposition (CH{sub 3}NO{sub 2} + M {yields} CH{sub 3} + NO{sub 2} + M, where M = N{sub 2} /Ar) corresponds well to a law of first order. Arrhenius expressions corresponding to NM diluted either in N{sub 2} or in Ar were found as k{sub N2} = 10{sup 17.011} * exp(- 182.6 kJ/mole / R*T) and k{sub Ar} = 10{sup 17.574}*exp(-207 kJ/mole / R*T ) , respectively. A new reaction mechanism was then proposed, based on new experimental data for NM decomposition both in Ar and N{sub 2} and on three previously developed mechanisms. The new mechanism predicts well the decomposition of NM diluted in both N{sub 2} and Ar within the pressure and temperature range covered by the experiments. In parallel to, and following the decomposition experiments, oxidative experiments on the ignition delay times of NM/O{sub 2}/Ar mixtures were investigated over high temperature and low to high pressure ranges. These experiments were carried out with eight different mixtures of gaseous NM and oxygen diluted in argon, with pressures ranging between 44.3-600 kPa, and temperatures ranging between 842-1378 K. The oxidation experiments were divided into different categories according to the type of decomposition signals achieved. For signals with and without emission, the apparent quasi

  9. Sensitivity analysis of efficiency thermal energy storage on selected rock mass and grout parameters using design of experiment method

    International Nuclear Information System (INIS)

    Wołoszyn, Jerzy; Gołaś, Andrzej

    2014-01-01

    Highlights: • Paper propose a new methodology to sensitivity study of underground thermal storage. • Using MDF model and DOE technique significantly shorter of calculations time. • Calculation of one time step was equal to approximately 57 s. • Sensitivity study cover five thermo-physical parameters. • Conductivity of rock mass and grout material have a significant impact on efficiency. - Abstract: The aim of this study was to investigate the influence of selected parameters on the efficiency of underground thermal energy storage. In this paper, besides thermal conductivity, the effect of such parameters as specific heat, density of the rock mass, thermal conductivity and specific heat of grout material was investigated. Implementation of this objective requires the use of an efficient computational method. The aim of the research was achieved by using a new numerical model, Multi Degree of Freedom (MDF), as developed by the authors and Design of Experiment (DoE) techniques with a response surface. The presented methodology can significantly reduce the time that is needed for research and to determine the effect of various parameters on the efficiency of underground thermal energy storage. Preliminary results of the research confirmed that thermal conductivity of the rock mass has the greatest impact on the efficiency of underground thermal energy storage, and that other parameters also play quite significant role

  10. 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.

  11. Thermal-hydraulic experiment and analysis for interim dry storage of spent nuclear fuel

    International Nuclear Information System (INIS)

    Yoo, Seung Hun

    2011-02-01

    The experimental and numerical studies of interim storages for nuclear spent fuels have been performed to investigate thermal-hydraulic characteristics of the dry storage systems and to propose new methodologies for the analysis and the design. Three separate researches have been performed in the present study: (a) Development of a scaling methodology and thermal-hydraulic experiment of a single spent fuel assembly simulating a dry storage cask: (b) Full-scope simulation of a dry storage cask by the use of Computational Fluid Dynamics (CFD) code: (c) Thermal-hydraulic design of a tunnel-type interim storage facility. In the first study, a scaling methodology has been developed to design a scaled-down canister. The scaling was performed in two steps. For the first step, the height of a spent fuel assembly was reduced from full height to half height. In order to consider the effect of height reduction on the natural convection, the scaling law of Ishii and Kataoka (1984) was employed. For the second step, the quantity of spent fuel assemblies was reduced from multiple assemblies to a single assembly. The scaling methodology was validated through the comparison with the experiment of the TN24P cask. The Peak Cladding Temperature (PCT), temperature gradients, and the axial and radial temperature distribution in the nondimensional forms were in good agreement with the experimental data. Based on the developed methodology, we have performed a single assembly experiment which was designed to simulate the full scale of the TN24P cask. The experimental data was compared with the CFD calculations. It turns out that their PCTs were less than the maximum allowable temperature for the fuel cladding and that the differences of their PCTs were agreed within 3 .deg. C, which was less than measurement uncertainty. In the second study, the full-scope simulations of the TN24P cask were performed by FLUENT. In order to investigate the sensitivity of the numerical and physical

  12. 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.

  13. 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...

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. Recrystallization Experiments of Pyrite From Circulating Hydrothermal Solution by Thermal Convection

    Science.gov (United States)

    Tanaka, K.; Isobe, H.

    2005-12-01

    Pyrite is one of the most common accessory minerals in many rocks and generally occurs in hydrothermal deposit. However, pyrite morphology and association with other sulfide minerals is not well known with respect to the solution condition, especially with the hydrothermal solution under circulation. In this study, recrystallization experiments of pyrite from circulating hydrothermal solution by thermal convection were carried out. A rectangular circuit (42.6 cm by 17.3 cm) of SUS316 pressure tubing with 5 mm in inner diameter was used as a reaction vessel. The volume of the circuit is approximately 24 ml. Long sides of the rectangular circuit were held to be 20 degrees inclination. One of the long sides was heated by an electric furnace. Solution in the circuit evaporates in the high temperature tubing and the vapor condenses in room temperature tubing. The solution backs to the bottom of the high temperature tubing. Thus, thermal convection of the solution produces circulation in the circuit. Starting material was filled in the high temperature tubing. The lower half was filled with mixture of 2 g of powdered natural pyrite and 4 g of quartz grains. The upper half was filled with quartz grains only. 9 ml of 5 mol/l NH4Cl solution was sealed in the circuit with the starting material. Temperature gradient of the sample was monitored by 6 thermocouples. Maximum temperature was controlled at 350°C. Experimental durations are 3, 5, 10 and 30 days. After the experiments, the run products are fixed with resin and cut every 2 cm. Thin sections of vertical cross-sections are made and observed by microscope and SEM. Tiny pyrite crystals occurred at the upper outside of the furnace, where temperature should be much lower than 200°C. In the lower half of the starting material, pyrite decomposed and pyrrhotite formed around pyrite grains. At higher temperature area, pyrite decomposition and pyrrhotite formation is remarkable. Circulating sulfur-bearing solution provided by

  19. Quantitative experiments on thermal hydraulic characteristics of an annular tube with twisted fins

    International Nuclear Information System (INIS)

    Ezato, Koichiro; Dairaku, Masayuki; Taniguchi, Masaki; Sato, Kazuyoshi; Suzuki, Satoshi; Akiba, Masato

    2003-11-01

    Thermal hydraulic experiments measuring critical heat flux (CHF) and pressure drop of an annular tube with twisted fins, ''annular swirl tube'', has been performed to examine its applicability to the ITER divertor cooling structure. The annular swirl tube consists of two concentric circular tubes, the outer and inner tubes. The outer tube with outer and inner diameters (OD and ID) of 21 mm and 15 mm is made of Cu-alloy that is CuCrZr and oe of candidate materials of the ITER divertor cooling tube. The inner tube with OD of 11 mm and ID of 9 mm is made of stainless steal. It has an external swirl fin with twist ratio (y) of three to enhance its heat transfer performance. In this tube, cooling water flows inside of the inner tube first, and then returns into an annulus between the outer and inner tubes with a swirl flow at an end-return of the cooling tube. The CHF experiments show that no degradation of CHF of the annular swirl tube in comparison with the conventional swirl tube whose dimensions are similar to those of the outer tube of the annular swirl tube. A minimum axial velocity of 7.1 m/s is required to remove the incident heat flux of 28MW/m 2 , the ITER design value. Applicability of the JAERI's correlation for the heat transfer to the annular swirl tube is also demonstrated by comparing the experimental results with those of the numerical analysis. The friction factor correlation for the annular flow with the twisted fins is also proposed for the hydrodynamic design of the ITER vertical target. The least pressure drop at the end-return is obtained by using the hemispherical end-plug. Its radius is the same as that of ID of the outer cooling tube. These results show that thermal-hydraulic performance of the annular swirl tube is promising in application to the cooling structure for the ITER vertical target. (author)

  20. Green primary explosives: 5-nitrotetrazolato-N2-ferrate hierarchies.

    Science.gov (United States)

    Huynh, My Hang V; Coburn, Michael D; Meyer, Thomas J; Wetzler, Modi

    2006-07-05

    The sensitive explosives used in initiating devices like primers and detonators are called primary explosives. Successful detonations of secondary explosives are accomplished by suitable sources of initiation energy that is transmitted directly from the primaries or through secondary explosive boosters. Reliable initiating mechanisms are available in numerous forms of primers and detonators depending upon the nature of the secondary explosives. The technology of initiation devices used for military and civilian purposes continues to expand owing to variations in initiating method, chemical composition, quantity, sensitivity, explosive performance, and other necessary built-in mechanisms. Although the most widely used primaries contain toxic lead azide and lead styphnate, mixtures of thermally unstable primaries, like diazodinitrophenol and tetracene, or poisonous agents, like antimony sulfide and barium nitrate, are also used. Novel environmentally friendly primary explosives are expanded here to include cat[Fe(II)(NT)(3)(H(2)O)(3)], cat(2)[Fe(II)(NT)(4)(H(2)O)(2)], cat(3)[Fe(II)(NT)(5)(H(2)O)], and cat(4)[Fe(II)(NT)(6)] with cat = cation and NT(-) = 5-nitrotetrazolato-N(2). With available alkaline, alkaline earth, and organic cations as partners, four series of 5-nitrotetrazolato-N(2)-ferrate hierarchies have been prepared that provide a plethora of green primaries with diverse initiating sensitivity and explosive performance. They hold great promise for replacing not only toxic lead primaries but also thermally unstable primaries and poisonous agents. Strategies are also described for the systematic preparation of coordination complex green primaries based on appropriate selection of ligands, metals, and synthetic procedures. These strategies allow for maximum versatility in initiating sensitivity and explosive performance while retaining properties required for green primaries.

  1. Embodied thermal environments: an examination of older-people's sensory experiences in a variety of residential types

    International Nuclear Information System (INIS)

    Henshaw, Victoria; Guy, Simon

    2015-01-01

    Thermal sensations of space, namely temperature, humidity and the movement of air, can be difficult to separate from other sensory information such as the sound of fans or ventilation equipment, or the smell of damp or cool fresh air. Despite this factor, efforts to reduce the consumption of energy through the installation of low-carbon technologies including sealed whole-building systems frequently isolate the thermal environment and fail to recognise and respond to the influence of other sensory information on personal preferences and behaviours. Older people represent an increasing proportion of the UK's population, can be faced with a range of physiological challenges associated with ageing, and sometimes have long-established personal preferences. Drawing from data collected across the Conditioning Demand Project, this paper explores the embodied nature of older people's experiences of low-carbon and more traditional thermal technologies in private residences, extra-care housing and residential care-homes, focussing specifically upon auditory and olfactory stimulus. Exploring the management of the sensory experience across these settings, we analyse each case to inform the development of new design and policy approaches to tackling housing for older people. In doing so, we further build connections between energy research and debates around sensory urbanism. -- Highlights: •Some thermal technologies present particular sensory issues and problems for older people. •Older people use a range of sensory stimuli in evaluating and controlling thermal environments. •Older people use non-thermal sensory information when selecting between thermal technologies. •Sensory information plays an important role in thermal technology maintenance

  2. Thermal stability of detonation-produced micro and nanodiamonds

    Science.gov (United States)

    Efremov, V. P.; Zakatilova, E. I.; Maklashova, I. V.; Shevchenko, N. V.

    2018-01-01

    Detonation nanodiamonds are produced at utilization of high explosives. When an explosive blasts in a water environment, the detonation products contain microdiamonds, and in a gaseous medium, nanodiamonds. It is known that with decreasing size the influence of the surface energy of particles on their properties increases. Thus, it is interesting to compare the properties of detonation nano and microdiamonds. In this study, we have examined the thermal stability of diamond materials by synchronous thermal analysis. The experiments were performed at atmospheric pressure in argon flow for different heating rates in a range from room temperature to 1500 °C. Samples of initial and annealed micro and nanomaterials were studied using electron microscopy, x-ray and x-ray-fluorescence analysis. It was established that thermal and structural properties of micro and nanodiamonds differ substantially.

  3. 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.

  4. Pressure vessel fracture studies pertaining to a PWR LOCA-ECC thermal shock: experiments TSE-1 and TSE-2

    International Nuclear Information System (INIS)

    Cheverton, R.D.

    1976-09-01

    The LOCA-ECC Thermal Shock Program was established to investigate the potential for flaw propagation in pressurized-water reactor (PWR) vessels during injection of emergency core coolant following a loss-of-coolant accident. Studies thus far have included fracture mechanics analyses of typical PWRs, the design and construction of a thermal shock test facility, determination of material properties for test specimens, and two thermal shock experiments with 0.53-m-OD (21-in.) by 0.15-m-wall (6-in.) cylindrical test specimens. The PWR calculations indicated that under some circumstances crack propagation could be expected and that experiments should be conducted for cracks that would have the potential for propagation at least halfway through the wall

  5. Thermal stability and kinetics of decomposition of ammonium nitrate in the presence of pyrite

    International Nuclear Information System (INIS)

    Gunawan, Richard; Zhang Dongke

    2009-01-01

    The interaction between ammonium nitrate based industrial explosives and pyrite-rich minerals in mining operations can lead to the occurrence of spontaneous explosion of the explosives. In an effort to provide a scientific basis for safe applications of industrial explosives in reactive mining grounds containing pyrite, ammonium nitrate decomposition, with and without the presence of pyrite, was studied using a simultaneous Differential Scanning Calorimetry and Thermogravimetric Analyser (DSC-TGA) and a gas-sealed isothermal reactor, respectively. The activation energy and the pre-exponential factor of ammonium nitrate decomposition were determined to be 102.6 kJ mol -1 and 4.55 x 10 7 s -1 without the presence of pyrite and 101.8 kJ mol -1 and 2.57 x 10 9 s -1 with the presence of pyrite. The kinetics of ammonium nitrate decomposition was then used to calculate the critical temperatures for ammonium nitrate decomposition with and without the presence of pyrite, based on the Frank-Kamenetskii model of thermal explosion. It was shown that the presence of pyrite reduces the temperature for, and accelerates the rate of, decomposition of ammonium nitrate. It was further shown that pyrite can significantly reduce the critical temperature of ammonium nitrate decomposition, causing undesired premature detonation of the explosives. The critical temperature also decreases with increasing diameter of the blast holes charged with the explosive. The concept of using the critical temperature as indication of the thermal stability of the explosives to evaluate the risk of spontaneous explosion was verified in the gas-sealed isothermal reactor experiments.

  6. Thermal stability and kinetics of decomposition of ammonium nitrate in the presence of pyrite.

    Science.gov (United States)

    Gunawan, Richard; Zhang, Dongke

    2009-06-15

    The interaction between ammonium nitrate based industrial explosives and pyrite-rich minerals in mining operations can lead to the occurrence of spontaneous explosion of the explosives. In an effort to provide a scientific basis for safe applications of industrial explosives in reactive mining grounds containing pyrite, ammonium nitrate decomposition, with and without the presence of pyrite, was studied using a simultaneous Differential Scanning Calorimetry and Thermogravimetric Analyser (DSC-TGA) and a gas-sealed isothermal reactor, respectively. The activation energy and the pre-exponential factor of ammonium nitrate decomposition were determined to be 102.6 kJ mol(-1) and 4.55 x 10(7)s(-1) without the presence of pyrite and 101.8 kJ mol(-1) and 2.57 x 10(9)s(-1) with the presence of pyrite. The kinetics of ammonium nitrate decomposition was then used to calculate the critical temperatures for ammonium nitrate decomposition with and without the presence of pyrite, based on the Frank-Kamenetskii model of thermal explosion. It was shown that the presence of pyrite reduces the temperature for, and accelerates the rate of, decomposition of ammonium nitrate. It was further shown that pyrite can significantly reduce the critical temperature of ammonium nitrate decomposition, causing undesired premature detonation of the explosives. The critical temperature also decreases with increasing diameter of the blast holes charged with the explosive. The concept of using the critical temperature as indication of the thermal stability of the explosives to evaluate the risk of spontaneous explosion was verified in the gas-sealed isothermal reactor experiments.

  7. Ground Testing a Nuclear Thermal Rocket: Design of a sub-scale demonstration experiment

    Energy Technology Data Exchange (ETDEWEB)

    David Bedsun; Debra Lee; Margaret Townsend; Clay A. Cooper; Jennifer Chapman; Ronald Samborsky; Mel Bulman; Daniel Brasuell; Stanley K. Borowski

    2012-07-01

    In 2008, the NASA Mars Architecture Team found that the Nuclear Thermal Rocket (NTR) was the preferred propulsion system out of all the combinations of chemical propulsion, solar electric, nuclear electric, aerobrake, and NTR studied. Recently, the National Research Council committee reviewing the NASA Technology Roadmaps recommended the NTR as one of the top 16 technologies that should be pursued by NASA. One of the main issues with developing a NTR for future missions is the ability to economically test the full system on the ground. In the late 1990s, the Sub-surface Active Filtering of Exhaust (SAFE) concept was first proposed by Howe as a method to test NTRs at full power and full duration. The concept relied on firing the NTR into one of the test holes at the Nevada Test Site which had been constructed to test nuclear weapons. In 2011, the cost of testing a NTR and the cost of performing a proof of concept experiment were evaluated.

  8. A review of conventional explosives detection using active neutron interrogation

    International Nuclear Information System (INIS)

    Whetstone, Z.D.; Kearfott, K.J.

    2014-01-01

    Conventional explosives are relatively easy to obtain and may cause massive harm to people and property. There are several tools employed by law enforcement to detect explosives, but these can be subverted. Active neutron interrogation is a viable alternative to those techniques, and includes: fast neutron analysis, thermal neutron analysis, pulsed fast/thermal neutron analysis, neutron elastic scatter, and fast neutron radiography. These methods vary based on neutron energy and radiation detected. A thorough review of the principles behind, advantages, and disadvantages of the different types of active neutron interrogation is presented. (author)

  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. Differences in coupling between chemical and nuclear explosions

    International Nuclear Information System (INIS)

    Glenn, L.A.

    1992-01-01

    The teleseismic amplitude resulting from an underground explosion is proportional to the asymptotic value of the reduced displacement potential (φ∞) or, in physical terms, to the permanent change in volume measured anywhere beyond the range at which the outgoing wave has become elastic. φ∞ decreases with increasing initial cavity size (r o ) until the cavity is large enough to preclude inelastic behavior in the surrounding rock, at which point no further decrease occurs. With nuclear explosions, φ∞ can also be reduced by decreasing the initial cavity size over a certain range. This occurs because, in this range of r 0 W -1/3 (where W is the yield) the thermal pressure in the surrounding medium increases much more slowly than does the thermal energy. With chemical explosions, by contrast, r 0 W -1/3 cannot be decreased below the fully tamped limit because the energy density is bounded above. Moreover, for the most of the cavity expansion period the ratio of specific heats of the chemical explosion products is substantially higher than the equivalent ratio in a nuclear explosion, so that the cavity pressure in the former case is higher as well and this further amplifies the differences between the two. Calculations show that the teleseismic amplitude could be as much as 50% higher for an equivalent tamped chemical explosion in salt than was observed in the SALMON nuclear event

  11. Lower head integrity under steam explosion loads

    Energy Technology Data Exchange (ETDEWEB)

    Theofanous, T.G.; Yuen, W.W.; Angelini, S.; Freeman, K.; Chen, X.; Salmassi, T. [Center for Risk Studies and Safety, Univ. of California, Santa Barbara, CA (United States); Sienicki, J.J.

    1998-01-01

    Lower head integrity under steam explosion loads in an AP600-like reactor design is considered. The assessment is the second part of an evaluation of the in-vessel retention idea as a severe accident management concept, the first part (DOE/ID-10460) dealing with thermal loads. The assessment is conducted in terms of the Risk Oriented Accident Analysis Methodology (ROAAM), and includes the comprehensive evaluation of all relevant severe accident scenarios, melt conditions and timing of release from the core region, fully 3D mixing and explosion wave dynamics, and lower head fragility under local, dynamic loading. All of these factors and brought together in a ROAAM Probabilistic Framework to evaluate failure likelihood. The conclusion is that failure is `physically unreasonable`. (author)

  12. PWR boron dilution transients. Thermal-hydraulic analyses of PKL-E experiments

    International Nuclear Information System (INIS)

    Pietro Alessandro Di Maio; Antonino Tomasello; Giuseppe Vella

    2005-01-01

    Full text of publication follows: In the field of PWR reactor safety, one of the topics that is currently of major interest worldwide is that of inadvertent boron dilution events. The safety issue involved in such scenarios is that inadvertent transport into the reactor core of un-borated water - or water having only a low boron concentration - can lead to local recriticality and possibly to power excursions. Studies on various accidental sequences that could initiate boron dilution events revealed that some SBLOCAs, occurring in the primary system, lead to reflux condenser conditions and subsequent re-establishment of natural circulation are of particular significance. In this work, the first field of analysis is related to the investigation of the thermal - hydraulic conditions that could lead to boron dilution events, such as the stop of natural circulation within primary system and the subsequent start of reflux condenser functioning mode. The investigation of the primary thermal - hydraulic conditions has been performed using the experimental results obtained in the PKL test integral facility in which some SBLOCA sequences have been carried out. Particular useful were the PKL III E experiments data whose results have been numerically reproduced using the code Relap5/MOD3.3/Beta code, contributing to understand the complex thermalhydraulic phenomena related to a PWR boron dilution event. The second field of analysis is related to the effects that possible displacements of un-borated water slugs towards the Reactor Pressure Vessel (RPV) could have on the core reactivity. A numerical approach using the Relap5 reactor kinetics model has been adopted to integrate the experimental thermal - hydraulic data obtained in the PKL III E tests. A careful analysis has been performed in order to establish which core conditions at incident start could produce the largest reactivity increase as a consequence of restarting of natural circulation during the primary system

  13. PWR boron dilution transients. Thermal-hydraulic analyses of PKL-E experiments

    Energy Technology Data Exchange (ETDEWEB)

    Pietro Alessandro Di Maio; Antonino Tomasello; Giuseppe Vella [Dipartimento di Ingegneria Nucleare, Viale delle Scienze, 90128 Palermo (Italy)

    2005-07-01

    Full text of publication follows: In the field of PWR reactor safety, one of the topics that is currently of major interest worldwide is that of inadvertent boron dilution events. The safety issue involved in such scenarios is that inadvertent transport into the reactor core of un-borated water - or water having only a low boron concentration - can lead to local recriticality and possibly to power excursions. Studies on various accidental sequences that could initiate boron dilution events revealed that some SBLOCAs, occurring in the primary system, lead to reflux condenser conditions and subsequent re-establishment of natural circulation are of particular significance. In this work, the first field of analysis is related to the investigation of the thermal - hydraulic conditions that could lead to boron dilution events, such as the stop of natural circulation within primary system and the subsequent start of reflux condenser functioning mode. The investigation of the primary thermal - hydraulic conditions has been performed using the experimental results obtained in the PKL test integral facility in which some SBLOCA sequences have been carried out. Particular useful were the PKL III E experiments data whose results have been numerically reproduced using the code Relap5/MOD3.3/Beta code, contributing to understand the complex thermalhydraulic phenomena related to a PWR boron dilution event. The second field of analysis is related to the effects that possible displacements of un-borated water slugs towards the Reactor Pressure Vessel (RPV) could have on the core reactivity. A numerical approach using the Relap5 reactor kinetics model has been adopted to integrate the experimental thermal - hydraulic data obtained in the PKL III E tests. A careful analysis has been performed in order to establish which core conditions at incident start could produce the largest reactivity increase as a consequence of restarting of natural circulation during the primary system

  14. Simulation of thermal phenomena expected in fuel coolant interactions in LMFBRs

    International Nuclear Information System (INIS)

    Yasin, J.

    1976-12-01

    High pressures and mechanical work may result when thermal energy is transferred from molten fuel to the coolant in a Liquid Metal Fast Breeder Reactor core meltdown accident. Two aspects of the interaction are examined in the thesis. First, the formation of high pressure pulses termed ''Vapor Explosions,'' and second, the distribution of the molten material into smaller particles, termed ''Fragmentation'', are studied. To understand the nature of the interaction simulant materials were used. Molten bismuth, molten tin and molten glass were dropped into water under various conditions. The interactions were recorded using multiflash and high speed photographing techniques. The pressure pulses were measured using transducers and the debris was examined by photographing them with an electron microscope. It was observed that vapor explosions have thresholds which depend on the material being dropped, its temperature and the bath conditions. The vapor explosions were enhanced by stratifying the bath. It was also noticed that the intensity of the vapor explosion depends on the way the molten drop fragmented in the initial stages of the interaction. The experiments with glass showed that the mode of fragmentation is important in determining when and if a vapor explosion is to be expected. The glass fragmented extensively but without any accompanying vapor explosion. The electron microscope photographs of the glass debris showed that thermal stress and surface tension phenomenon are apparently the cause of the fragmentation

  15. Dual Phase Change Thermal Diodes for Enhanced Rectification Ratios: Theory and Experiment

    KAUST Repository

    Cottrill, Anton L.; Wang, Song; Liu, Albert Tianxiang; Wang, Wen-Jun; Strano, Michael S.

    2018-01-01

    Thermal diodes are materials that allow for the preferential directional transport of heat and are highly promising devices for energy conservation, energy harvesting, and information processing applications. One form of a thermal diode consists of the junction between a phase change and phase invariant material, with rectification ratios that scale with the square root of the ratio of thermal conductivities of the two phases. In this work, the authors introduce and analyse the concept of a Dual Phase Change Thermal Diode (DPCTD) as the junction of two phase change materials with similar phase boundary temperatures but opposite temperature coefficients of thermal conductivity. Such systems possess a significantly enhanced optimal scaling of the rectification ratio as the square root of the product of the thermal conductivity ratios. Furthermore, the authors experimentally design and fabricate an ambient DPCTD enabled by the junction of an octadecane-impregnated polystyrene foam, polymerized using a high internal phase emulsion template (PFH-O) and a poly(N-isopropylacrylamide) (PNIPAM) aqueous solution. The DPCTD shows a significantly enhanced thermal rectification ratio both experimentally (2.6) and theoretically (2.6) as compared with ideal thermal diodes composed only of the constituent materials.

  16. Model Experiment of Thermal Runaway Reactions Using the Aluminum-Hydrochloric Acid Reaction

    Science.gov (United States)

    Kitabayashi, Suguru; Nakano, Masayoshi; Nishikawa, Kazuyuki; Koga, Nobuyoshi

    2016-01-01

    A laboratory exercise for the education of students about thermal runaway reactions based on the reaction between aluminum and hydrochloric acid as a model reaction is proposed. In the introductory part of the exercise, the induction period and subsequent thermal runaway behavior are evaluated via a simple observation of hydrogen gas evolution and…

  17. Dual Phase Change Thermal Diodes for Enhanced Rectification Ratios: Theory and Experiment

    KAUST Repository

    Cottrill, Anton L.

    2018-01-15

    Thermal diodes are materials that allow for the preferential directional transport of heat and are highly promising devices for energy conservation, energy harvesting, and information processing applications. One form of a thermal diode consists of the junction between a phase change and phase invariant material, with rectification ratios that scale with the square root of the ratio of thermal conductivities of the two phases. In this work, the authors introduce and analyse the concept of a Dual Phase Change Thermal Diode (DPCTD) as the junction of two phase change materials with similar phase boundary temperatures but opposite temperature coefficients of thermal conductivity. Such systems possess a significantly enhanced optimal scaling of the rectification ratio as the square root of the product of the thermal conductivity ratios. Furthermore, the authors experimentally design and fabricate an ambient DPCTD enabled by the junction of an octadecane-impregnated polystyrene foam, polymerized using a high internal phase emulsion template (PFH-O) and a poly(N-isopropylacrylamide) (PNIPAM) aqueous solution. The DPCTD shows a significantly enhanced thermal rectification ratio both experimentally (2.6) and theoretically (2.6) as compared with ideal thermal diodes composed only of the constituent materials.

  18. 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

  19. Structures to Resist the Effects of Accidental Explosions. Volume 6. Special Considerations in Explosive Facility Design

    Science.gov (United States)

    1985-04-01

    addition to their Inherent advantages with respect to fire protection, acoustical and thermal insulation, structural mass and resistance to flying...suspended from a monorail system. The panel is inside the shield and is not rigidly attached to the column members. Special consideration was given to...characteristic pulse emitted by an explosion to prevent actuation by other sources such as lightning, fires , etc., **ich cay occur with flash sensors. ■112

  20. 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)

  1. A DSC analysis of inverse salt-pair explosive composition

    Energy Technology Data Exchange (ETDEWEB)

    Babu, E. Suresh; Kaur, Sukhminder [Central Forensic Science Laboratory, Explosives Division, Ramanthapur, Hyderabad 500013 (India)

    2004-02-01

    Alkali nitrates are used as an ingredient in low explosive compositions and pyrotechnics. It has been suggested that alkali nitrates can form inverse salt-pair explosives with the addition of ammonium chloride. Therefore, the thermal behavior of low explosive compositions containing potassium nitrate mixed with ammonium chloride has been studied using Differential Scanning Calorimetry (DSC). Results provide information about the ion exchange reaction between these two chemical substances and the temperature region at which the formation of a cloud of salt particles of potassium chloride takes place. Furthermore, the addition of ammonium chloride quenches the flame of deflagrating compositions and causes the mixture to undergo explosive decomposition at relatively low temperatures. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  2. Thermal Expansion of Ni3Al Intermetallic Compound: Experiment and Simulation

    International Nuclear Information System (INIS)

    Wang Hai-Peng; Lü Peng; Zhou Kai; Wei Bing-Bo

    2016-01-01

    The thermal expansion of Ni 3 Al intermetallic compound is determined by a thermal dilatometer and simulated by the molecular dynamics method. The results of the linear thermal expansion coefficients are presented from 200 K up to the maximum temperature of 1600 K. The single phase of Ni 3 Al intermetallic compound is confirmed by x-ray diffraction together with DSC melting and solidification peaks, from which the solidus and the liquidus temperatures are obtained to be 1660 and 1695 K, respectively. The measured linear thermal expansion coefficient increases from 1.5 × 10 −5 to 2.7 × 10 −5 K −1 in the experimental temperature range, in good agreement with the data obtained by the molecular dynamics simulation, just a slight difference from the temperature dependence coefficient. Furthermore, the atomic structure and position are presented to reveal the atom distribution change during thermal expansion of Ni 3 Al compound. (paper)

  3. 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.

  4. FOREVER Experiments on Thermal and Mechanical Behavior of a Reactor Pressure Vessel during a Severe Accident

    International Nuclear Information System (INIS)

    Sehgal, B.R.; Nourgaliev, R.R.; Dinh, T.N.; Karbojian, A.; Green, J.A.; Bui, V.A.

    1999-01-01

    This paper describes the FOREVER (Failure Of Reactor Vessel Retention) experimental program, which is currently underway at the Division of Nuclear Power Safety, Royal Institute of Technology (RIT/NPS). The objectives of the FOREVER experiments are to obtain data and develop validated models (i) on the melt coolability process inside the vessel, in the presence of water (in particular, on the efficacy of the postulated gap cooling to preclude vessel failure); and (ii) on the lower head failure due to the creep process in the absence of water inside and/or outside the lower head. The facility employs 1/10.-scale carbon steel vessels of 0.4 m diameter, 15 mm thickness and 600 mm height. Up to 20 liters of binary-oxide melts with 100-300 K superheat are employed, as a simulant for the prototypic corium melt, and internal heating is provided by electrical heaters of up to 20 kW power in order to maintain the vessel wall temperatures at 1100-1200 K. Auxiliary systems are designed to provide an overpressure up to 4 MPa in the test vessel. Thus, severe accident scenarios with RCS depressurization are modeled. Creep behavior of the three-dimensional vessel, formation of the gap between the melt pool crust and the creeping vessel, and mechanisms of the gap cooling by water ingression will be the subjects of study and measurements in the FOREVER experimental program. Scaling rationale as well as pre-test analyses of the thermal and mechanical behavior of the FOREVER test vessels are presented. (authors)

  5. ICRF power deposition profile and determination of the electron thermal diffusivity by modulation experiments in JET

    International Nuclear Information System (INIS)

    Gambier, D.J.; Evrard, M.P.; Adam, J.

    1990-01-01

    The power deposition profile in the ion cyclotron range of frequencies (ICRF) has been investigated experimentally in JET by means of a square wave modulated RF perturbation. The study has been conducted in D(H) and D( 3 He) plasmas for two heating scenarios. In D( 3 He) plasmas and for central heating in a scenario where mode conversion to Bernstein waves is accessible, the direct power deposition profile on electrons has been derived. It accounts for 15% of the total coupled power and extends over 25% of the minor radius. Outside the RF power deposition zone, the electron thermal diffusivity χ e inside the inversion radius surface (r i ) can be estimated through observation of the diffusive electronic transport. In discharges without monster sawteeth and for a low central temperature gradient (∇T e (r ≤ r i ) ≤ ∇T e (r ≥ r i ) approx. = 5 keV·m -1 ) the value obtained is small (approx. =0.24 +- 0.05 m 2 · s -1 ), typically ten times lower than χ e values deduced from heat pulse propagation in similar discharges at radii larger than the inversion radius. For the D(H) minority heating scheme, a large fraction of the ICRF modulated power is absorbed by minority ions, and the minority tail is modulated with a characteristic ion-electron (i-e) slowing-down time. In this scheme, electron heating occurs only through collisions with the minority ion tail and no modulation of the electron temperature is observed in sawtoothing discharges. This is interpreted as a consequence of the long i-e equipartition time, acting as an integrator for the modulated ICRF signal. Finally, a correlation between the time of the sawtooth crash and the periodic turn-off of the ICRF power is found and its consequence for modulation experiments is reviewed. (author). 22 refs, 16 figs

  6. Thermal analysis of laser additive manufacturing of aluminium alloys: Experiment and simulation

    Science.gov (United States)

    Bock, Frederic E.; Froend, Martin; Herrnring, Jan; Enz, Josephin; Kashaev, Nikolai; Klusemann, Benjamin

    2018-05-01

    Laser additive manufacturing (LAM) has become increasingly popular in industry in recent decades because it enables exceptional degrees of freedom regarding the structural design of lightweight components compared to subtractive manufacturing techniques. Laser metal deposition (LMD) of wire-fed material shows in particular the advantages such as high process velocity and efficient use of material compared to other LAM processes. During wire-based LMD, the material is deposited onto a substrate and supplemented by successive layers allowing a layer-wise production of complex three-dimensional structures. Despite the increased productivity of LMD, regarding the ability to process aluminium alloys, there is still a lack in quality and reproducibility due to the inhomogeneous temperature distribution during the process, leading to undesired residual stresses, distortions and inconsistent layer geometries and poor microstructures. In this study, the aluminium alloy AA5087 as wire and AA5754 as substrate material were utilized for LMD. In order to obtain information about the temperature field during LMD, thermocouple and thermography measurements were performed during the process. The temperature measurements were used to validate a finite element model regarding the heat distribution, which will be further used to investigate the temperature field evolution over time. To consider the continuous addition of material within the FE-model, an inactive/active element approach was chosen, where initially deactivated elements are activated corresponding to the deposition of material. The first results of the simulation and the experiments show good agreement. Therefore, the model can be used in the future for LMD process optimization, e.g., in terms of minimizing local variations of the thermal load for each layer.

  7. Design Studies for a Multiple Application Thermal Reactor for Irradiation Experiments (MATRIX)

    Energy Technology Data Exchange (ETDEWEB)

    Pope, Michael A.; Gougar, Hans D.; Ryskamp, J. M.

    2015-03-01

    The Advanced Test Reactor (ATR) is a high power density test reactor specializing in fuel and materials irradiation. For more than 45 years, the ATR has provided irradiations of materials and fuels testing along with radioisotope production. Should unforeseen circumstances lead to the decommissioning of ATR, the U.S. Government would be left without a large-scale materials irradiation capability to meet the needs of its nuclear energy and naval reactor missions. In anticipation of this possibility, work was performed under the Laboratory Directed Research and Development (LDRD) program to investigate test reactor concepts that could satisfy the current missions of the ATR along with an expanded set of secondary missions. A survey was conducted in order to catalogue the anticipated needs of potential customers. Then, concepts were evaluated to fill the role for this reactor, dubbed the Multi-Application Thermal Reactor Irradiation eXperiments (MATRIX). The baseline MATRIX design is expected to be capable of longer cycle lengths than ATR given a particular batch scheme. The volume of test space in In-Pile-Tubes (IPTs) is larger in MATRIX than in ATR with comparable magnitude of neutron flux. Furthermore, MATRIX has more locations of greater volume having high fast neutron flux than ATR. From the analyses performed in this work, it appears that the lead MATRIX design can be designed to meet the anticipated needs of the ATR replacement reactor. However, this design is quite immature, and therefore any requirements currently met must be re-evaluated as the design is developed further.

  8. Research of thermal stability of ion exchangers

    International Nuclear Information System (INIS)

    Stuchlik, S.; Srnkova, J.

    1983-01-01

    Prior to the fixation of radioactive ion exchangers into bitumen these exchangers have to be dried. The resulting gaseous products may generate explosive mixtures. An analysis was made of the thermal stability of two types of ion exchangers, the cation exchanger KU-2-8 cS and the anion exchanger AV-17-8 cS which are used in the V-1 nuclear power plant at Jaslovske Bohunice. The thermal stability of the anion exchangers was monitored using gas chromatography at temperatures of 100, 120, 140, 160 and 180 degC and by measuring weight loss by kiln-drying at temperatures of 120, 140, 160 and 180 degC. The ion exchanger was heated for 6 hours and samples were taken continuously at one hour intervals. The thermal stability of the cation exchanger was monitored by measuring the weight loss. Gas chromatography showed the release of trimethylamine from the anion exchanger in direct dependence on temperature. The measurement of weight losses, however, only showed higher losses of released products which are explained by the release of other thermally unstable products. The analysis of the thermal stability of the cation exchanger showed the release of SO 2 and the weight loss (following correction for water content) was found only after the fourth hour of decomposition. The experiment showed that the drying of anion exchanger AV-17-8 cS may cause the formation of explosive mixtures. (J.P.)

  9. Fracture-mechanics data deduced from thermal-shock and related experiments with LWR pressure-vessel material

    International Nuclear Information System (INIS)

    Cheverton, R.D.; Canonico, D.A.; Iskander, S.K.; Bolt, S.E.; Holz, P.P.; Nanstad, R.K.; Stelzman, W.J.

    1982-01-01

    Pressurized water reactors (PWRs) are susceptible to certain types of hypothetical accidents that can subject the reactor pressure vessel to severe thermal shock, that is, a rapid cooling of the inner surface of the vessel wall. The thermal-shock loading, coupled with the radiation-induced reduction in the material fracture toughness, introduces the possibility of propagation of preexistent flaws and what at one time were regarded as somewhat unique fracture-oriented conditions. Several postulated reactor accidents have been analyzed to discover flaw behavior trends; seven intermediate-scale thermal-shock experiments with steel cylinders have been conducted; and corresponding materials characterization studies have been performed. Flaw behavior trends and related fracture-mechanics data deduced from these studies are discussed

  10. Fundamental validation of simulation method for thermal stratification in upper plenum of fast reactors. Analysis of sodium experiment

    International Nuclear Information System (INIS)

    Ohno, Shuji; Ohshima, Hiroyuki; Sugahara, Akihiro; Ohki, Hiroshi

    2010-01-01

    Three-dimensional thermal-hydraulic analyses have been carried out for a sodium experiment in a relatively simple axis-symmetric geometry using a commercial CFD code in order to validate simulating methods for thermal stratification behavior in an upper plenum of sodium-cooled fast reactor. Detailed comparison between simulated results and experimental measurement has demonstrated that the code reproduced fairly well the fundamental thermal stratification behaviors such as vertical temperature gradient and upward movement of a stratification interface when utilizing high-order discretization scheme and appropriate mesh size. Furthermore, the investigation has clarified the influence of RANS type turbulence models on phenomena predictability; i.e. the standard k-ε model, the RNG k-ε model and the Reynolds Stress Model. (author)

  11. Two-state model of light induced activation and thermal bleaching of photochromic glasses: theory and experiments

    International Nuclear Information System (INIS)

    Ferrari, Jose A.; Perciante, Cesar D.

    2008-01-01

    The behavior of photochromic glasses during activation and bleaching is investigated. A two-state phenomenological model describing light-induced activation (darkening) and thermal bleaching is presented. The proposed model is based on first-order kinetics. We demonstrate that the time behavior in the activation process (acting simultaneously with the thermal fading) can be characterized by two relaxation times that depend on the intensity of the activating light. These characteristic times are lower than the decay times of the pure thermal bleaching process. We study the temporal evolution of the glass optical density and its dependence on the activating intensity. We also present a series of activation and bleaching experiments that validate the proposed model. Our approach may be used to gain more insight into the transmittance behavior of photosensitive glasses, which could be potentially relevant in a broad range of applications, e.g., real-time holography and reconfigurable optical memories

  12. Thermal and stress analyses of meltdown cups for LMFBR safety experiments using SLSF in-reactor loops

    International Nuclear Information System (INIS)

    Blomquist, C.A.; Pierce, R.D.; Pedersen, D.R.; Ariman, T.

    1977-01-01

    The test trains for the Sodium Loop Safety Facility (SLSF) in-reactor experiments, which simulate hypothetical LMFBR accidents, have a meltdown cup to protect the primary containment from the effects of molten materials. Thermal and stress analyses were performed on the cup which is designed to contain 3.6 kg of molten fuel and 2.4 kg of molten steel. Thermal analyses were performed with the Argonne-modified version fo the general heat transfer code THTB, based on the instantaneous addition of 3200 0 K molten fuel with a decay heat of 9 W/gm and 1920 0 K molten steel. These analyses have shown that the cup will adequately cool the molten materials. The stress analysis showed that the Inconel vessel would not fail from the pressure loading, it was also shown that brittle fracture of the tungsten liner from thermal gradients is unlikely. Therefore, the melt-down cup meets the structural design requirements. (Auth.)

  13. Sensitivity Evaluation of the Daily Thermal Predictions of the AGR-1 Experiment in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Grant Hawkes; James Sterbentz; John Maki

    2011-05-01

    A temperature sensitivity evaluation has been performed for the AGR-1 fuel experiment on an individual capsule. A series of cases were compared to a base case by varying different input parameters into the ABAQUS finite element thermal model. These input parameters were varied by ±10% to show the temperature sensitivity to each parameter. The most sensitive parameters are the outer control gap distance, heat rate in the fuel compacts, and neon gas fraction. Thermal conductivity of the compacts and graphite holder were in the middle of the list for sensitivity. The smallest effects were for the emissivities of the stainless steel, graphite, and thru tubes. Sensitivity calculations were also performed varying with fluence. These calculations showed a general temperature rise with an increase in fluence. This is a result of the thermal conductivity of the fuel compacts and graphite holder decreasing with fluence.

  14. Thermal model of in-situ experiment of 32nd level Mysore mine, KGF. Report No. 1

    International Nuclear Information System (INIS)

    Narayan, P.K.; Mathur, R.K.; Godse, V.B.; Sunder Rajan, N.S.

    1985-01-01

    Canisters with immobilised high level radioactive wastes require isolation from the biosphere and need to be disposed of in a deep geological media so that radionuclides in the waste are contained in the media for extended period of time. Several countries are evaluating various host rocks for their suitability for location of a geological respository for such work. One of the main thrust of the present work in these countries is in conducting in-situ heater experiment to study the behaviour of the host rock at elevated temperature. The main purpose of the experiment is to evalutate the integrity of the rock by observing the propagation of microfractures consequent to thermal loading. This type of study would lead to optimisation of the spacing and depth of the bore holes and thus the economic usage of space deep underground. In India such thermomechanical experiments have been planned in abandoned chamber of Mysore and Nundydoorg mines of Kolar Gold Fields at the depths of about 1000m-1500m. The scope of the work detailed in this report is to provide guidance to the in situ experiment by developing thermal and thermomechanical models and to generate field data base of various thermal properties of the host rock to facilitate validation of the model. In addition it is also intended to form a basis for developing other complex models which can predict stresses and displacements. (author)

  15. Thermal adaptation and phenotypic plasticity in a warming world: Insights from common garden experiments on Alaskan sockeye salmon

    Science.gov (United States)

    Sparks, Morgan M.; Westley, Peter A. H.; Falke, Jeffrey A.; Quinn, Thomas P.

    2017-01-01

    An important unresolved question is how populations of coldwater-dependent fishes will respond to rapidly warming water temperatures. For example, the culturally and economically important group, Pacific salmon (Oncorhynchus spp.), experience site-specific thermal regimes during early development that could be disrupted by warming. To test for thermal local adaptation and heritable phenotypic plasticity in Pacific salmon embryos, we measured the developmental rate, survival, and body size at hatching in two populations of sockeye salmon (Oncorhynchus nerka) that overlap in timing of spawning but incubate in contrasting natural thermal regimes. Using a split half-sibling design, we exposed embryos of 10 families from each of two populations to variable and constant thermal regimes. These represented both experienced temperatures by each population, and predicted temperatures under plausible future conditions based on a warming scenario from the downscaled global climate model (MIROC A1B scenario). We did not find evidence of thermal local adaptation during the embryonic stage for developmental rate or survival. Within treatments, populations hatched within 1 day of each other, on average, and amongtreatments, did not differ in survival in response to temperature. We did detect plasticity to temperature; embryos developed 2.5 times longer (189 days) in the coolest regime compared to the warmest regime (74 days). We also detected variation in developmental rates among families within and among temperature regimes, indicating heritable plasticity. Families exhibited a strong positive relationship between thermal variability and phenotypic variability in developmental rate but body length and mass at hatching were largely insensitive to temperature. Overall, our results indicated a lack of thermal local adaptation, but a presence of plasticity in populations experiencing contrasting conditions, as well as family-specific heritable plasticity that could

  16. 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.

  17. Next-Generation Thermal Infrared Multi-Body Radiometer Experiment (TIMBRE)

    Science.gov (United States)

    Kenyon, M.; Mariani, G.; Johnson, B.; Brageot, E.; Hayne, P.

    2016-10-01

    We have developed an instrument concept called TIMBRE which belongs to the important class of instruments called thermal imaging radiometers (TIRs). TIMBRE is the next-generation TIR with unparalleled performance compared to the state-of-the-art.

  18. Using Coupled Mesoscale Experiments and Simulations to Investigate High Burn-Up Oxide Fuel Thermal Conductivity

    Science.gov (United States)

    Teague, Melissa C.; Fromm, Bradley S.; Tonks, Michael R.; Field, David P.

    2014-12-01

    Nuclear energy is a mature technology with a small carbon footprint. However, work is needed to make current reactor technology more accident tolerant and to allow reactor fuel to be burned in a reactor for longer periods of time. Optimizing the reactor fuel performance is essentially a materials science problem. The current understanding of fuel microstructure have been limited by the difficulty in studying the structure and chemistry of irradiated fuel samples at the mesoscale. Here, we take advantage of recent advances in experimental capabilities to characterize the microstructure in 3D of irradiated mixed oxide (MOX) fuel taken from two radial positions in the fuel pellet. We also reconstruct these microstructures using Idaho National Laboratory's MARMOT code and calculate the impact of microstructure heterogeneities on the effective thermal conductivity using mesoscale heat conduction simulations. The thermal conductivities of both samples are higher than the bulk MOX thermal conductivity because of the formation of metallic precipitates and because we do not currently consider phonon scattering due to defects smaller than the experimental resolution. We also used the results to investigate the accuracy of simple thermal conductivity approximations and equations to convert 2D thermal conductivities to 3D. It was found that these approximations struggle to predict the complex thermal transport interactions between metal precipitates and voids.

  19. 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.

  20. Reactive thermal waves in energetic materials

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Larry G [Los Alamos National Laboratory

    2009-01-01

    Reactive thermal waves (RTWs) arise in several energetic material applications, including self-propagating high-temperature synthesis (SHS), high explosive cookoff, and the detonation of heterogeneous explosives. In this paper I exmaine ideal RTWs, by which I mean that (1) material motion is neglected, (2) the state dependence of reaction is Arrhenius in the temperature, and (3) the reaction rate is modulated by an arbitrary mass-fraction-based reaction progress function. Numerical simulations demonstrate that one's natural intuition, which is based mainly upon experience with inert materials and which leads one to expect diffusion processes to become relatively slow after a short time period, is invalid for high energy, state-sensitive reactive systems. Instead, theory predicts that RTWs can propagate at very high speeds. This result agrees with estimates for detonating heterogeneous explosives, which indicate that RTWs must spread from hot-spot nucleation sites at rates comparable to the detonation speed in order to produce experimentally-observed reaction zone thicknesses. Using dimensionless scaling and further invoking the high activation energy approximation, I obtain an analytic formula for the steady plane RTW speed from numerical calculations. I then compute the RTW speed for real explosives, and discuss aspects of their behavior.

  1. 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

  2. Apparatus and method for detecting explosives

    International Nuclear Information System (INIS)

    Griffith, B.

    1976-01-01

    An apparatus is described for use in situations such as airports to detect explosives hidden in containers (for eg. suitcases). The method involves the evaluation of the quantities of oxygen and nitrogen within the container by neutron activation analysis and the determination of whether these quantities exceed predetermined limits. The equipment includes a small sub-critical lower powered reactor for thermal (0.01 to 0.10 eV) neutron production, a radium beryllium primary source, a deuterium-tritium reactor as a high energy (> 1.06 MeV) neutron source and Geiger counter detector arrays. (UK)

  3. Effects of neutrino trapping on supernova explosions

    International Nuclear Information System (INIS)

    Takahara, Mariko; Sato, Katsuhiko

    1982-01-01

    Effects of neutrino trapping on the mass ejection from the stellar cores are investigated with the aid of a simplified equation of state under the assumption of adiabatic collapse. It is found that mass ejection becomes violent only if the ratio of the trapped leptons to baryons, Y sub(L), lies in an appropriate range. If the value of Y sub(L) lies out of this range, mass ejection is difficult. It is also shown that as the thermal stiffness of the shocked matter increases, the range necessary for the violent mass ejection becomes wider. Possibilities of supernova explosion are discussed on the basis of these results. (author)

  4. A TNA explosives-detection system in airline baggage

    Energy Technology Data Exchange (ETDEWEB)

    Shea, P.; Gozani, T. (Science Applications International Corp., Santa Clara, CA (USA)); Bozorgmanesh, H. (Science Applications International Corp., San Diego, CA (USA))

    1990-12-20

    Existing technologies that are applied to explosives-detection in passenger baggage are briefly discussed. A system based on thermal-neutron analysis (TNA) is described. The actual performance of the system in the field on passenger bags is given. The application of the TNA in an integrated airport security system is discussed in view of the intense public debate on this issue. (orig.).

  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. Structure of the marine atmospheric boundary layer over an oceanic thermal front: SEMAPHORE experiment

    Science.gov (United States)

    Kwon, B. H.; BéNech, B.; Lambert, D.; Durand, P.; Druilhet, A.; Giordani, H.; Planton, S.

    1998-10-01

    The Structure des Echanges Mer-Atmosphere, Proprietes des Heterogeneites Oceaniques: Recherche Experimentale (SEMAPHORE) experiment, the third phase of which took place between October 4 and November 17, 1993, was conducted over the oceanic Azores Current located in the Azores basin and mainly marked at the surface by a thermal front due to the gradient of the sea surface temperature (SST) of about 1° to 2°C per 100 km. The evolution of the marine atmospheric boundary layer (MABL) over the SST front was studied with two aircraft and a ship in different meteorological conditions. For each case, the influence of the incoming air direction with respect to the orientation of the oceanic front was taken into account. During the campaign, advanced very high resolution radiometer pictures did not show any relation between the SST field and the cloud cover. The MABL was systematically thicker on the warm side than on the cold side. The mean MABL structure described from aircraft data collected in a vertical plane crossing the oceanic front was characterized by (1) an atmospheric horizontal gradient of 1° to 2°C per 100 km in the whole depth of the mixed layer and (2) an increase of the wind intensity from the cold to the warm side when the synoptic wind blew from the cold side. The surface sensible heat (latent heat) flux always increased from the cold to the warm sector owing to the increase of the wind and of the temperature (specific humidity) difference between the surface and the air. Turbulence increased from the cold to the warm side in conjunction with the MABL thickening, but the normalized profiles presented the same structure, regardless of the position over the SST front. In agreement with the Action de Recherche Programme te Petite Echelle and Grande Echelle model, the mean temperature and momentum budgets were highly influenced by the horizontal temperature gradient. In particular, the strong ageostrophic influence in the MABL above the SST front seems

  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. 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

  9. 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.

  10. 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)

  11. Parametric dependence of density limits in the Tokamak Experiment for Technology Oriented Research (TEXTOR): Comparison of thermal instability theory with experiment

    International Nuclear Information System (INIS)

    Kelly, F.A.; Stacey, W.M.; Rapp, J.

    2001-01-01

    The observed dependence of the TEXTOR [Tokamak Experiment for Technology Oriented Research: E. Hintz, P. Bogen, H. A. Claassen et al., Contributions to High Temperature Plasma Physics, edited by K. H. Spatschek and J. Uhlenbusch (Akademie Verlag, Berlin, 1994), p. 373] density limit on global parameters (I, B, P, etc.) and wall conditioning is compared with the predicted density limit parametric scaling of thermal instability theory. It is necessary first to relate the edge parameters of the thermal instability theory to n(bar sign) and the other global parameters. The observed parametric dependence of the density limit in TEXTOR is generally consistent with the predicted density limit scaling of thermal instability theory. The observed wall conditioning dependence of the density limit can be reconciled with the theory in terms of the radiative emissivity temperature dependence of different impurities in the plasma edge. The thermal instability theory also provides an explanation of why symmetric detachment precedes radiative collapse for most low power shots, while a multifaceted asymmetric radiation from the edge MARFE precedes detachment for most high power shots

  12. Effect of metal stress on the thermal infrared emission of soybeans: A greenhouse experiment - Possible utility in remote sensing

    Science.gov (United States)

    Suresh, R.; Schwaller, M. R.; Foy, C. D.; Weidner, J. R.; Schnetzler, C. S.

    1989-01-01

    Manganese-sensitive forest and manganese-tolerant lee soybean cultivars were subjected to differential manganese stress in loring soil in a greenhouse experiment. Leaf temperature measurements were made using thermistors for forest and lee. Manganese-stressed plants had higher leaf temperatures than control plants in both forest and lee. Results of this experiment have potential applications in metal stress detection using remote sensing thermal infrared data over large areas of vegetation. This technique can be useful in reconnaissance mineral exploration in densely-vegetated regions where conventional ground-based methods are of little help.

  13. Laser induced fluorescence thermometry (LIF-T) as a non-invasive temperature measurement technique for thermal hydraulic experiments

    Energy Technology Data Exchange (ETDEWEB)

    Strack, J.; Leung, K.; Walker, A., E-mail: strackj@mcmaster.ca [McMaster Univ., Hamilton, ON (Canada)

    2014-07-01

    Laser induced fluorescence (LIF) is an experimental technique whereby a scalar field in a fluid system is measured optically from the fluorescence intensity of a tracer dye following excitation by laser light. For laser induced fluorescence thermometry (LIF-T), a temperature sensitive dye is used. Through the use of a temperature sensitive tracer dye, sheet laser optics, optical filters, and photography, a 2D temperature field can be measured non-invasively. An experiment to test the viability of using LIF-T for macroscopic thermal hydraulic experiments was developed and tested. A reference calibration curve to relate fluorescence measurements to temperature is presented. (author)

  14. 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

  15. 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...

  16. 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...

  17. Thermal performance of a radiatively cooled system for quantum optomechanical experiments in space

    International Nuclear Information System (INIS)

    Pilan Zanoni, André; Burkhardt, Johannes; Johann, Ulrich; Aspelmeyer, Markus; Kaltenbaek, Rainer; Hechenblaikner, Gerald

    2016-01-01

    Highlights: • We improved performance and design aspects of a radiatively cooled instrument. • A heat-flow analysis showed near optimal performance of the shield design. • A simple modification to imaging optics allowed further improvements. • We studied the thermal behavior for different orbital cases. • A transfer-function analysis showed strong attenuation of thermal variations. - Abstract: Passive cooling of scientific instruments via thermal radiation to deep space offers many advantages over active cooling in terms of mission cost, lifetime and the achievable quality of vacuum and microgravity. Motivated by the mission proposal MAQRO to test the foundations of quantum physics harnessing a deep-space environment, we investigate the performance of a radiatively cooled instrument, where the environment of a test particle in a quantum superposition has to be cooled to less than 20 K. We perform a heat-transfer analysis between the instrument components and a transfer-function analysis on thermal oscillations induced by the spacecraft interior and dissipative sources. The thermal behavior of the instrument is discussed for an orbit around a Lagrangian point and for a highly elliptical Earth orbit. Finally, we investigate possible design improvements. These include a mirror-based design of the imaging system on the optical bench (OB) and an extension of the heat shields.

  18. Thermal properties of methane hydrate by experiment and modeling and impacts upon technology

    Energy Technology Data Exchange (ETDEWEB)

    Warzinski, R.P.; Gamwo, I.K.; Rosenbaum, E.J. [United States Dept. of Energy, Pittsburgh, PA (United States). National Energy Technology Laboratory; Myshakin, E.M. [NETL Support Contractor, South Park, PA (United States); Jiang, H.; Jordan, K.D. [Pittsburgh Univ., Pittsburgh, PA (United States). Dept. of Chemistry; English, N.J. [Dublin University College, Dublin (Ireland). Conway Inst. of Biomolecular and Biomedical Research, Centre for Synthesis and Chemical Biology; Shaw, D.W. [Geneva College, Beaver Falls, PA (United States). Dept. of Engineering

    2008-07-01

    The current hydrate research at the National Energy Technology Laboratory (NETL) involves both experimental and theoretical work on developing models and methods for predicting the behaviour of gas hydrates in their natural environment under production of climate change scenarios. The modeling efforts include both fundamental and reservoir scale simulations and economic modeling. The thermal properties of methane hydrate are important for hydrate production, seafloor stability and climate change scenarios. A new experimental technique and advanced molecular dynamics simulation (MDS) have determined the thermal properties of pure methane hydrate under conditions similar to naturally occurring hydrate-bearing sediments. The thermal conductivity and thermal diffusivity values of low-porosity methane hydrate formed in the laboratory were measured using an innovative single-sided, Transient Plane Source (TPS) technique. The results were in good agreement with results from an equilibrium MDS method using in-plane polarization of the water molecules. MDS was also performed using a non-equilibrium model with a fully polarizable force field for water. The Tough+Hydrate reservoir simulator was also used to evaluate the impact of thermal conductivity on gas production from a hydrate-bearing reservoir. 42 refs., 1 tab., 5 figs.

  19. Experiment and Artificial Neural Network Prediction of Thermal Conductivity and Viscosity for Alumina-Water Nanofluids.

    Science.gov (United States)

    Zhao, Ningbo; Li, Zhiming

    2017-05-19

    To effectively predict the thermal conductivity and viscosity of alumina (Al₂O₃)-water nanofluids, an artificial neural network (ANN) approach was investigated in the present study. Firstly, using a two-step method, four Al₂O₃-water nanofluids were prepared respectively by dispersing different volume fractions (1.31%, 2.72%, 4.25%, and 5.92%) of nanoparticles with the average diameter of 30 nm. On this basis, the thermal conductivity and viscosity of the above nanofluids were analyzed experimentally under various temperatures ranging from 296 to 313 K. Then a radial basis function (RBF) neural network was constructed to predict the thermal conductivity and viscosity of Al₂O₃-water nanofluids as a function of nanoparticle volume fraction and temperature. The experimental results showed that both nanoparticle volume fraction and temperature could enhance the thermal conductivity of Al₂O₃-water nanofluids. However, the viscosity only depended strongly on Al₂O₃ nanoparticle volume fraction and was increased slightly by changing temperature. In addition, the comparative analysis revealed that the RBF neural network had an excellent ability to predict the thermal conductivity and viscosity of Al₂O₃-water nanofluids with the mean absolute percent errors of 0.5177% and 0.5618%, respectively. This demonstrated that the ANN provided an effective way to predict the thermophysical properties of nanofluids with limited experimental data.

  20. 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)

  1. Open inquiry-based learning experiences: a case study in the context of energy exchange by thermal radiation

    International Nuclear Information System (INIS)

    PERG (University of Palermo, Physics Education Research Group) Dipartimento di Fisica e Chimica, Università di Palermo, Palermo (Italy))" data-affiliation=" (UOPPERG (University of Palermo, Physics Education Research Group) Dipartimento di Fisica e Chimica, Università di Palermo, Palermo (Italy))" >Pizzolato, Nicola; PERG (University of Palermo, Physics Education Research Group) Dipartimento di Fisica e Chimica, Università di Palermo, Palermo (Italy))" data-affiliation=" (UOPPERG (University of Palermo, Physics Education Research Group) Dipartimento di Fisica e Chimica, Università di Palermo, Palermo (Italy))" >Fazio, Claudio; PERG (University of Palermo, Physics Education Research Group) Dipartimento di Fisica e Chimica, Università di Palermo, Palermo (Italy))" data-affiliation=" (UOPPERG (University of Palermo, Physics Education Research Group) Dipartimento di Fisica e Chimica, Università di Palermo, Palermo (Italy))" >Battaglia, Onofrio Rosario

    2014-01-01

    An open inquiry (OI)-based teaching/learning experience, regarding a scientific investigation of the process of energy exchange by thermal radiation, is presented. A sample of upper secondary school physics teachers carried out this experience at the University of Palermo, Italy, in the framework of ESTABLISH, a FP7 European Project aimed at promoting and developing inquiry-based science education. The teachers had the opportunity to personally experience an OI-based learning activity, with the aim of exploring the pedagogical potentialities of this teaching approach to promote both the understanding of difficult concepts and a deeper view of scientific practices. The teachers were firstly engaged in discussions concerning real-life problematic situations, and then stimulated to design and carry out their own laboratory activities, aimed at investigating the process of energy exchange by thermal radiation. A scientific study on the energy exchange between a powered resistor and its surrounding environment, during the heating and cooling processes, was designed and performed. Here we report the phases of this experiment by following the teachers' perspective. A structured interview conducted both before and after the OI experience allowed us to analyze and point out the teachers' feedback from a pedagogical point of view. The advantages and limits of an OI-based approach to promote the development of more student-centred inquiry-oriented teaching strategies are finally discussed. (paper)

  2. 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)

  3. 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)

  4. MEMS-based Porous Silicon Preconcentrators Filled with Carbopack-B for Explosives Detection

    OpenAIRE

    Camara , El Hadji Malik; James , Franck; Breuil , Philippe; Pijolat , Christophe; Briand , Danick; De Rooij , Nicolaas F

    2014-01-01

    International audience; In this paper we report the detection of explosive compounds using a miniaturized gas preconcentrator (μGP) made of porous silicon (PS) filled in with Carbopack B as an adsorbent material. The μGP includes also a platinum heater patterned at the backside and fluidic connectors sealed on the glass cover. Our μGP is designed and optimized through fluidic and thermal simulations for meeting the requirements of trace explosives detection. The thermal mass of the device was...

  5. Analysis of core physics and thermal-hydraulics results of control rod withdrawal experiments in the LOFT facility

    International Nuclear Information System (INIS)

    Varacalle, D.J. Jr.; Chen, T.H.; Harvego, E.A.; Ollikkala, H.

    1983-01-01

    Two anticipated transient experiments simulating an uncontrolled control rod withdrawal event in a pressurized water reactor (PWR) were conducted in the Loss-of-Fluid Test (LOFT) Facility at the Idaho National Engineering Laboratory. The scaled LOFT 50-MW(t) PWR includes most of the principal features of larger commercial PWRs. The experiments tested the ability of reactor analysis codes to accurately calculate core reactor physics and thermal-hydraulic phenomena in an integral reactor system. The initial conditions and scaled operating parameters for the experiments were representative of those expected in a commercial PWR. In both experiments, all four LOFT control rod assemblies were withdrawn at a reactor power of 37.5 MW and a system pressure of 14.8 MPa

  6. Experiment and numerical analysis of the NPP pressurizer auxiliary spray line submitted to large thermal shocks

    International Nuclear Information System (INIS)

    Couterot, C.; Geyer, P.; Proix, J.M.

    1994-03-01

    The pressurizer auxiliary spray line of PWR nuclear power plants may be submitted to severe temperature transients during upset conditions: a 325 deg C cold thermal shock in one second is followed by a 200 deg C hot thermal shock. For such transients, the RCC-M French design code rules that prevent the ratcheting deformation hazard are not respected for the components with thickness transition. Consequently, Electricite de France has realized twenty thermal cycles under pressure on a representative mock-up. During these tests, many temperature, strain and diametral variations were measured. No significant ratcheting deformation was detected on all components, except on the 6'' x 2'' x 6'' T-piece, where a weak progressive diameter increase was observed during a few cycles. Moreover, computations of a 2'' socket welding were made with the non linear kinematic hardening Chaboche model which also showed a weak progressive deformation behaviour. (authors). 7 figs., 7 refs

  7. Refractometric sensitivity and thermal stabilization of fluorescent core microcapillary sensors: theory and experiment.

    Science.gov (United States)

    Lane, S; Marsiglio, F; Zhi, Y; Meldrum, A

    2015-02-20

    Fluorescent-core microcapillaries (FCMs) present a robust basis for the application of optical whispering gallery modes toward refractometric sensing. An important question concerns whether these devices can be rendered insensitive to local temperature fluctuations, which may otherwise limit their refractometric detection limits, mainly as a result of thermorefractive effects. Here, we first use a standard cylindrical cavity formalism to develop the refractometric and thermally limited detection limits for the FCM structure. We then measure the thermal response of a real device with different analytes in the channel and compare the result to the theory. Good stability against temperature fluctuations was obtained for an ethanol solvent, with a near-zero observed thermal shift for the transverse magnetic modes. Similarly good results could in principle be obtained for any other solvent (e.g., water), if the thickness of the fluorescent layer can be sufficiently well controlled.

  8. 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.

  9. 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

  10. Calculated thermally induced displacements and stresses for heater experiments at Stripa, Sweden. Linear thermoelastic models using constant material properties

    International Nuclear Information System (INIS)

    Chan, T.; Cook, N.G.W.

    1979-12-01

    Thermally induced displacements and stresses have been calculated by finite element analysis to guide the design, operation, and data interpretation of the in situ heating experiments in a granite formation at Stripa, Sweden. There are two full-scale tests with electrical heater canisters comparable in size and power to those envisaged for reprocessed high level waste canisters and a time-scaled test. To provide a simple theoretical basis for data analysis, linear thermoelasticity was assumed. Constant (temperature-independent) thermal and mechanical rock properties were used in the calculations. These properties were determined by conventional laboratory testing on small intact core specimens recovered from the Stripa test site. Two-dimensional axisymmetric models were used for the full-scale experiments, and three-dimensional models for the time-scaled experiment. Highest compressive axial and tangential stresses are expected at the wall of the heater borehole. For the 3.6 kW full-scale heated experiment, maximum compressive tangential stress was predicted to be below the unconfined compressive strength of Stripa granite, while for the 5 kW experiment, the maximum was approximately equal to the compressive strength before the concentric ring of eight 1 kW peripheral heaters was activated, but would exceed that soon afterwards. Three zones of tensile thermomechanical stresses will occur in each full-scale experiment. Maximum vertical displacements range from a fraction of a millimeter over most of the instrumented area of the time-scaled experiment to a few millimeters in the higher-power full-scale experiment. Radial displacements are typically half or less than vertical displacements. The predicted thermomechanical displacements and stresses have been stored in an on-site computer to facilitate instant graphic comparison with field data as the latter are collected

  11. MCNP benchmark analyses of critical experiments for space nuclear thermal propulsion

    International Nuclear Information System (INIS)

    Selcow, E.C.; Cerbone, R.J.; Ludewig, H.

    1993-01-01

    The particle-bed reactor (PBR) system is being developed for use in the Space Nuclear Thermal Propulsion (SNTP) Program. This reactor system is characterized by a highly heterogeneous, compact configuration with many streaming pathways. The neutronics analyses performed for this system must be able to accurately predict reactor criticality, kinetics parameters, material worths at various temperatures, feedback coefficients, and detailed fission power and heating distributions. The latter includes coupled axial, radial, and azimuthal profiles. These responses constitute critical inputs and interfaces with the thermal-hydraulics design and safety analyses of the system

  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. 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

  14. Application of factor analysis to the explosive detection

    International Nuclear Information System (INIS)

    Park, Yong Joon; Song, Byung Chul; Im, Hee Jung; Kim, Won Ho; Cho, Jung Hwan

    2005-01-01

    The detection of explosive devices hidden in airline baggage is significant problem, particularly in view of the development of modern plastic explosives which can formed into various innocent-appearing shapes and which are sufficiently powerful that small quantities can destroy an aircraft in flight. Besides, the biggest difficulty occurs from long detection time required for the explosive detection system based on thermal neutron interrogation, which involves exposing baggage to slow neutrons having energy in the order of 0.025 eV. The elemental compositions of explosives can be determined by the Neutron Induced Prompt gamma Spectroscopy (NIPS) which has been installed in Korea Atomic Energy Research Institute as a tool for the detection of explosives in passenger baggage. In this work, the factor analysis has been applied to the NIPS system to increase the signal-to-noise ratio of the prompt gamma spectrum for the detection of explosive hidden in a passenger's baggage, especially for the noisy prompt gamma spectrum obtained with short measurement time

  15. 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.

  16. An Analysis of the Initiation Process of Electro-Explosive Devices

    Directory of Open Access Journals (Sweden)

    Paulo Cesar de Carvalho Faria

    2012-03-01

    Full Text Available Electro-explosive devices (an electric resistance encapsulated by a primary explosive fundamentally convert electrical energy into thermal energy, to start off an explosive chemical reaction. Obviously, the activation of those devices shall not happen by accident or, even worse, by intentional exogenous influence. From an ordinary differential equation, which describes the electro-explosive thermal behavior, a remarkable, but certainly not intuitive, dependence of the temperature response on the time constant of the heat transfer process is verified: the temperature profile dramatically changes as the time constant spans a wide range of values, from much lesser than the pulse width to much greater than the pulse period. Based on this dependence, important recommendations, concerning the efficient and safety operation of electro-explosive devices, are proposed.

  17. 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.

  18. Internal sub-sonic burning during an explosion viewed via dynamic X-ray radiography

    Science.gov (United States)

    Smilowitz, L.; Henson, B. F.; Oschwald, D.; Suvorova, N.; Remelius, D.

    2017-10-01

    We observe internal convective and conductive burn front propagation and solid consumption subsequent to thermal ignition for plastic bonded formulations of the solid organic secondary explosives octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine and 1,3,5-triamino-2,4,6-trinitrobenzene. This work describes x-ray radiographic diagnostics enabling the study of solid density in a fully encased explosive during internal burning subsequent to ignition. The result of this study is the ability to directly observe and measure rates of energy release during a thermal explosion.

  19. THERMAL RESPONSE OF A SOLAR-LIKE ATMOSPHERE TO AN ELECTRON BEAM FROM A HOT JUPITER: A NUMERICAL EXPERIMENT

    International Nuclear Information System (INIS)

    Gu, P.-G.; Suzuki, Takeru K.

    2009-01-01

    We investigate the thermal response of the atmosphere of a solar-type star to an electron beam injected from a hot Jupiter by performing a one-dimensional MHD numerical experiment with nonlinear wave dissipation, radiative cooling, and thermal conduction. In our experiment, the stellar atmosphere is non-rotating and is modeled as a one-dimensional open flux tube expanding super-radially from the stellar photosphere to the planet. An electron beam is assumed to be generated from the reconnection site of the planet's magnetosphere. The effects of the electron beam are then implemented in our simulation as dissipation of the beam momentum and energy at the base of the corona where the Coulomb collisions become effective. When the sufficient energy is supplied by the electron beam, a warm region forms in the chromosphere. This warm region greatly enhances the radiative fluxes corresponding to the temperature of the chromosphere and transition region. The warm region can also intermittently contribute to the radiative flux associated with the coronal temperature due to the thermal instability. However, owing to the small area of the heating spot, the total luminosity of the beam-induced chromospheric radiation is several orders of magnitude smaller than the observed Ca II emissions from HD 179949.

  20. Study of the aluminothermic reduction of niobium pentoxide through thermal analysis experiments and high energy milling processing

    Directory of Open Access Journals (Sweden)

    Claudio Parra De Lazzari

    2007-06-01

    Full Text Available Aluminothermic reduction of niobium pentoxide was studied through thermal analysis techniques such as differential thermal analysis (DTA and thermogravimetry (TG as well as through high energy milling processing. Reactants mixtures were composed by powders of Nb2O5 and Al. In the case of DTA-TG experiments, different molar ratios Nb2O5:Al were heated in a dynamic atmosphere of synthetic air under controlled conditions. The high energy milling runs were carried out via SPEX vibratory mill under argon atmosphere and with milling power equal to 7:1 (ratio of mass of balls to mass of mixture with 10 pct excess of Al over the stoichiometric mass of aluminum necessary. In both kinds of experiments, X ray diffraction was used in order to identify the products of reaction. From DTA-TG experiments, it was possible to determine the experimental value of the enthalpy change (-595.9 kJ.mol-1, which is near to the theoretical one. From the milling experiments, it was possible to verify the possibility of the occurance of aluminothermic reducion of niobium pentoxide via this kind of processing.