Characterization of Microwave-Induced Electric Discharge Phenomena in Metal–Solvent Mixtures

PubMed Central

Chen, Wen; Gutmann, Bernhard; Kappe, C Oliver

2012-01-01

Electric discharge phenomena in metal–solvent mixtures are investigated utilizing a high field density, sealed-vessel, single-mode 2.45 GHz microwave reactor with a built-in camera. Particular emphasis is placed on studying the discharges exhibited by different metals (Mg, Zn, Cu, Fe, Ni) of varying particle sizes and morphologies in organic solvents (e.g., benzene) at different electric field strengths. Discharge phenomena for diamagnetic and paramagnetic metals (Mg, Zn, Cu) depend strongly on the size of the used particles. With small particles, short-lived corona discharges are observed that do not lead to a complete breakdown. Under high microwave power conditions or with large particles, however, bright sparks and arcs are experienced, often accompanied by solvent decomposition and formation of considerable amounts of graphitized material. Small ferromagnetic Fe and Ni powders (<40 μm) are heated very rapidly in benzene suspensions and start to glow in the microwave field, whereas larger particles exhibit extremely strong discharges. Electric discharges were also observed when Cu metal or other conductive materials such as silicon carbide were exposed to the microwave field in the absence of a solvent in an argon or nitrogen atmosphere. PMID:24551491

Characterization of microwave-induced electric discharge phenomena in metal-solvent mixtures.

PubMed

Chen, Wen; Gutmann, Bernhard; Kappe, C Oliver

2012-02-01

Electric discharge phenomena in metal-solvent mixtures are investigated utilizing a high field density, sealed-vessel, single-mode 2.45 GHz microwave reactor with a built-in camera. Particular emphasis is placed on studying the discharges exhibited by different metals (Mg, Zn, Cu, Fe, Ni) of varying particle sizes and morphologies in organic solvents (e.g., benzene) at different electric field strengths. Discharge phenomena for diamagnetic and paramagnetic metals (Mg, Zn, Cu) depend strongly on the size of the used particles. With small particles, short-lived corona discharges are observed that do not lead to a complete breakdown. Under high microwave power conditions or with large particles, however, bright sparks and arcs are experienced, often accompanied by solvent decomposition and formation of considerable amounts of graphitized material. Small ferromagnetic Fe and Ni powders (<40 μm) are heated very rapidly in benzene suspensions and start to glow in the microwave field, whereas larger particles exhibit extremely strong discharges. Electric discharges were also observed when Cu metal or other conductive materials such as silicon carbide were exposed to the microwave field in the absence of a solvent in an argon or nitrogen atmosphere.

Investigation on the influence of electrode geometry on characteristics of coaxial dielectric barrier discharge reactor driven by an oscillating microsecond pulsed power supply

NASA Astrophysics Data System (ADS)

Miao, Chuanrun; Liu, Feng; Wang, Qian; Cai, Meiling; Fang, Zhi

2018-03-01

In this paper, an oscillating microsecond pulsed power supply with rise time of several tens of nanosecond (ns) is used to excite a coaxial DBD with double layer dielectric barriers. The effects of various electrode geometries by changing the size of inner quartz tube (different electrode gaps) on the discharge uniformity, power deposition, energy efficiency, and operation temperature are investigated by electrical, optical, and temperature diagnostics. The electrical parameters of the coaxial DBD are obtained from the measured applied voltage and current using an equivalent electrical model. The energy efficiency and the power deposition in air gap of coaxial DBD with various electrode geometries are also obtained with the obtained electrical parameters, and the heat loss and operation temperature are analyzed by a heat conduction model. It is found that at the same applied voltage, with the increasing of the air gap, the discharge uniformity becomes worse and the discharge power deposition and the energy efficiency decrease. At 2.5 mm air gap and 24 kV applied voltage, the energy efficiency of the coaxial DBD reaches the maximum value of 68.4%, and the power deposition in air gap is 23.6 W and the discharge uniformity is the best at this case. The corresponding operation temperature of the coaxial DBD reaches 64.3 °C after 900 s operation and the temperature of the inner dielectric barrier is 114.4 °C under thermal balance. The experimental results provide important experimental references and are important to optimize the design and the performance of coaxial DBD reactor.

Effect of Electric Discharge on Properties of Nano-Particulate Catalyst for Plasma-Catalysis.

PubMed

Lee, Chung Jun; Kim, Jip; Kim, Taegyu

2016-02-01

Heterogeneous catalytic processes have been used to produce hydrogen from hydrocarbons. However, high reforming temperature caused serious catalyst deteriorations and low energy efficiency. Recently, a plasma-catalyst hybrid process was used to reduce the reforming temperature and to improve the stability and durability of reforming catalysts. Effect of electric discharges on properties of nanoparticulate catalysts for plasma-catalysis was investigated in the present study. Catalyst-bed porosity was varied by packing catalyst beads with the different size in a reactor. Discharge power and onset voltage of the plasma were measured as the catalyst-bed porosity was varied. The effect of discharge voltage, frequency and voltage waveforms such as the sine, pulse and square was investigated. We found that the optimal porosity of the catalyst-bed exists to maximize the electric discharge. At a low porosity, the electric discharge was unstable to be sustained because the space between catalysts got narrow nearly close to the sheath region. On the other hand, at a high porosity, the electric discharge became weak because the plasma was not sufficient to interact with the surface of catalysts. The discharge power increased as the discharge voltage and frequency increased. The square waveform was more efficient than the sine and pulse one. At a high porosity, however, the effect of the voltage waveform was not considerable because the space between catalysts was too large for plasma to interact with the surface of catalysts.

CORONA DISCHARGE REACTOR FOR SELECTIVE OXIDATION OF ALCOHOLS AND HYDROCARBONS USING OZONATION AND PHOTOXIDATION OF OVER TIO2

EPA Science Inventory

We have developed a process that combines the use of surface corona for the production of ozone by passing air or oxygen through a high voltage electrical discharge and the emitted UV is being used to activate a photocatalyst. A thin film of nanostructured TiO2 with primary part...

Scaling of surface-plasma reactors with a significantly increased energy density for NO conversion.

PubMed

Malik, Muhammad Arif; Xiao, Shu; Schoenbach, Karl H

2012-03-30

Comparative studies revealed that surface plasmas developing along a solid-gas interface are significantly more effective and energy efficient for remediation of toxic pollutants in air than conventional plasmas propagating in air. Scaling of the surface plasma reactors to large volumes by operating them in parallel suffers from a serious problem of adverse effects of the space charges generated at the dielectric surfaces of the neighboring discharge chambers. This study revealed that a conductive foil on the cathode potential placed between the dielectric plates as a shield not only decoupled the discharges, but also increased the electrical power deposited in the reactor by a factor of about forty over the electrical power level obtained without shielding and without loss of efficiency for NO removal. The shield had no negative effect on efficiency, which is verified by the fact that the energy costs for 50% NO removal were about 60 eV/molecule and the energy constant, k(E), was about 0.02 L/J in both the shielded and unshielded cases. Copyright © 2012 Elsevier B.V. All rights reserved.

Gas chemical studies using corona discharge reactors

NASA Astrophysics Data System (ADS)

Schulze, P.; Stankiewicz, A.; Aicher, M.; Mattner, M.; Ulrich, A.

2010-12-01

Corona discharges with voltages up to 60 kV (DC) were studied with the aim to induce chemical reactions in flue gases at atmospheric pressure. Various plasma reactors with different geometries of multi-needle arrays were tested. The power input was optimised by studying the electrical parameters of the set-up systematically. Both, solid and liquid electrodes were used in combination with the needle arrays. A precise positioning of the corona needles allowed operation without a ballast resistor. Formation rates for CO and the sum of NO2 and O3 are reported and discussed. Three catalytic anode-coatings were tested for their potential to decompose carbon dioxide.

CO2 Dissociation by Low Current Gliding Discharge in the Reverse Vortex Flow

NASA Astrophysics Data System (ADS)

Gutsol, Alexander

2012-10-01

If performed with high energy efficiency, plasma-chemical dissociation of carbon dioxide can be a way of converting and storing energy when there is an excess of electric energy, for example generated by solar elements of wind turbines. CO2 dissociation with efficiency of up to 90% was reported earlier for low pressure microwave discharge in supersonic flow. A new plasma-chemical system uses a low current gliding discharge in the reverse vortex flow of plasma gas. The system is a development of the Gliding Arc in Tornado reactor. The system was used to study dissociation of CO2 in wide ranges of the following experimental parameters: reactor pressure (15-150 kPa), discharge current (50-500 mA), gas flow rate (3-30 liters per minute), and electrode gap length (1-10 cm). Additionally, the effect of thermal energy recuperation on CO2 dissociation efficiency was tested. Plasma chemical efficiency of CO2 dissociation is very low (about 3%) in a short discharge at low pressures (about 15 kPa) when it is defined by electronic excitation. The highest efficiency (above 40%) was reached at pressures 50-70 kPa in a long discharge with thermal energy recuperation. It means that the process is controlled by thermal dissociation with subsequent effective quenching. Plasma chemical efficiency was determined from the data of chromatographic analysis and oscilloscope electric power integration, and also was checked calorimetrically by the thermal balance of the system.

Process scale-up considerations for non-thermal atmospheric-pressure plasma synthesis of nanoparticles by homogenous nucleation

NASA Astrophysics Data System (ADS)

Cole, Jonathan; Zhang, Yao; Liu, Tianqi; Liu, Chang-jun; Mohan Sankaran, R.

2017-08-01

Scale-up of non-thermal atmospheric-pressure plasma reactors for the synthesis of nanoparticles by homogeneous nucleation is challenging because the active volume is typically reduced to facilitate gas breakdown, enhance discharge stability, and limit particle size and agglomeration, but thus limits throughput. Here, we introduce a dielectric barrier discharge reactor consisting of a coaxial electrode geometry for nanoparticle production that enables a simple scale-up strategy whereby increasing the outer and inner electrode diameters, the plasma volume is increased approximately linearly, while maintaining a sufficiently small electrode gap to maintain the electric field strength. We show with two test reactors that for a given residence time, the nanoparticle production rate increases linearly with volume over a range of precursor concentrations, while having minimal effect on the shape of the particle size distribution. However, our study also reveals that increasing the total gas flow rate in a smaller volume reactor leads to an enhancement of precursor conversion and a comparable production rate to a larger volume reactor. These results suggest that scale-up requires better understanding of the influence of reactor geometry on particle growth dynamics and may not always be a simple function of reactor volume.

Apparatus for isotopic alteration of mercury vapor

DOEpatents

Grossman, Mark W.; George, William A.; Marcucci, Rudolph V.

1988-01-01

An apparatus for enriching the isotopic Hg content of mercury is provided. The apparatus includes a reactor, a low pressure electric discharge lamp containing a fill including mercury and an inert gas. A filter is arranged concentrically around the lamp. In a preferred embodiment, constant mercury pressure is maintained in the filter by means of a water-cooled tube that depends from it, the tube having a drop of mercury disposed in it. The reactor is arranged around the filter, whereby radiation from said lamp passes through the filter and into said reactor. The lamp, the filter and the reactor are formed of a material which is transparent to ultraviolet light.

Electrical description of N2 capacitively coupled plasmas with the global model

NASA Astrophysics Data System (ADS)

Cao, Ming-Lu; Lu, Yi-Jia; Cheng, Jia; Ji, Lin-Hong; Engineering Design Team

2016-10-01

N2 discharges in a commercial capacitively coupled plasma reactor are modelled by a combination of an equivalent circuit and the global model, for a range of gas pressure at 1 4 Torr. The ohmic and inductive plasma bulk and the capacitive sheath are represented as LCR elements, with electrical characteristics determined by plasma parameters. The electron density and electron temperature are obtained from the global model in which a Maxwellian electron distribution is assumed. Voltages and currents are recorded by a VI probe installed after the match network. Using the measured voltage as an input, the current flowing through the discharge volume is calculated from the electrical model and shows excellent agreement with the measurements. The experimentally verified electrical model provides a simple and accurate description for the relationship between the external electrical parameters and the plasma properties, which can serve as a guideline for process window planning in industrial applications.

Characteristics of a novel nanosecond DBD microplasma reactor for flow applications

NASA Astrophysics Data System (ADS)

Elkholy, A.; Nijdam, S.; van Veldhuizen, E.; Dam, N.; van Oijen, J.; Ebert, U.; de Goey, L. Philip H.

2018-05-01

We present a novel microplasma flow reactor using a dielectric barrier discharge (DBD) driven by repetitive nanosecond high-voltage pulses. Our DBD-based geometry can generate a non-thermal plasma discharge at atmospheric pressure and below in a regular pattern of micro-channels. This reactor can work continuously up to about 100 min in air, depending on the pulse repetition rate and operating pressure. We here present the geometry and main characteristics of the reactor. Pulse energies of 1.46 and 1.3 μJ per channel at atmospheric pressure and 50 mbar, respectively, have been determined by time-resolved measurements of current and voltage. Time-resolved optical emission spectroscopy measurements have been performed to calculate the relative species concentrations and temperatures (vibrational and rotational) of the discharge. The effects of the operating pressure and flow velocity on the discharge intensity have been investigated. In addition, the effective reduced electric field strength {(E/N)}eff} has been obtained from the intensity ratio of vibronic emission bands of molecular nitrogen at different operating pressures and different locations. The derived {(E/N)}eff} increases gradually from about 550 to 4600 Td when decreasing the pressure from 1 bar to 100 mbar. Below 100 mbar, further pressure reduction results in a significant increase in {(E/N)}eff} up to about 10000 Td at 50 mbar.

Pulsed Corona Discharge Generated By Marx Generator

NASA Astrophysics Data System (ADS)

Sretenovic, G. B.; Obradovic, B. M.; Kovacevic, V. V.; Kuraica, M. M.; Puric J.

2010-07-01

The pulsed plasma has a significant role in new environmental protection technologies. As a part of a pulsed corona system for pollution control applications, Marx type repetitive pulse generator was constructed and tested in arrangement with wire-plate corona reactor. We performed electrical measurements, and obtained voltage and current signals, and also power and energy delivered per pulse. Ozone formation by streamer plasma in air was chosen to monitor chemical activity of the pulsed corona discharge.

Removal of several pesticides in a falling water film DBD reactor with activated carbon textile: Energy efficiency.

PubMed

Vanraes, Patrick; Ghodbane, Houria; Davister, Dries; Wardenier, Niels; Nikiforov, Anton; Verheust, Yannick P; Van Hulle, Stijn W H; Hamdaoui, Oualid; Vandamme, Jeroen; Van Durme, Jim; Surmont, Pieter; Lynen, Frederic; Leys, Christophe

2017-06-01

Bio-recalcitrant micropollutants are often insufficiently removed by modern wastewater treatment plants to meet the future demands worldwide. Therefore, several advanced oxidation techniques, including cold plasma technology, are being investigated as effective complementary water treatment methods. In order to permit industrial implementation, energy demand of these techniques needs to be minimized. To this end, we have developed an electrical discharge reactor where water treatment by dielectric barrier discharge (DBD) is combined with adsorption on activated carbon textile and additional ozonation. The reactor consists of a DBD plasma chamber, including the adsorptive textile, and an ozonation chamber, where the DBD generated plasma gas is bubbled. In the present paper, this reactor is further characterized and optimized in terms of its energy efficiency for removal of the five pesticides α-HCH, pentachlorobenzene, alachlor, diuron and isoproturon, with initial concentrations ranging between 22 and 430 μg/L. Energy efficiency of the reactor is found to increase significantly when initial micropollutant concentration is decreased, when duty cycle is decreased and when oxygen is used as feed gas as compared to air and argon. Overall reactor performance is improved as well by making it work in single-pass operation, where water is flowing through the system only once. The results are explained with insights found in literature and practical implications are discussed. For the used operational conditions and settings, α-HCH is the most persistent pesticide in the reactor, with a minimal achieved electrical energy per order of 8 kWh/m 3 , while a most efficient removal of 3 kWh/m 3 or lower was reached for the four other pesticides. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spectroscopic diagnosis of plasma in atmospheric pressure negative pulsed gas-liquid discharge with nozzle-cylinder electrode

NASA Astrophysics Data System (ADS)

Ming, SUN; Zhan, TAO; Zhipeng, ZHU; Dong, WANG; Wenjun, PAN

2018-05-01

The plasma characteristics of a gas-liquid phase discharge reactor were investigated by optical and electrical methods. The nozzle-cylinder electrode in the discharge reactor was supplied with a negative nanosecond pulsed generator. The optical emission spectrum diagnosis revealed that OH (A2∑+ → X2Π, 306–309 nm), N2 (C3Π→B3Πg, 337 nm), O (3p5p→3s5s0, 777.2 nm) and O (3p3p→3s3s0, 844.6 nm) were produced in the discharge plasma channels. The electron temperature (T e) was calculated from the emission relative intensity ratio between the atomic O 777.2 nm and 844.6 nm, and it increased with the applied voltage and the pulsed frequency and fell within the range of 0.5–0.8 eV. The gas temperature (T g) that was measured by Lifbase was in a range from 400 K to 600 K.

Performance evaluation of two-stage fuel cycle from SFR to PWR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fei, T.; Hoffman, E.A.; Kim, T.K.

2013-07-01

One potential fuel cycle option being considered is a two-stage fuel cycle system involving the continuous recycle of transuranics in a fast reactor and the use of bred plutonium in a thermal reactor. The first stage is a Sodium-cooled Fast Reactor (SFR) fuel cycle with metallic U-TRU-Zr fuel. The SFRs need to have a breeding ratio greater than 1.0 in order to produce fissile material for use in the second stage. The second stage is a PWR fuel cycle with uranium and plutonium mixed oxide fuel based on the design and performance of the current state-of-the-art commercial PWRs with anmore » average discharge burnup of 50 MWd/kgHM. This paper evaluates the possibility of this fuel cycle option and discusses its fuel cycle performance characteristics. The study focuses on an equilibrium stage of the fuel cycle. Results indicate that, in order to avoid a positive coolant void reactivity feedback in the stage-2 PWR, the reactor requires high quality of plutonium from the first stage and minor actinides in the discharge fuel of the PWR needs to be separated and sent back to the stage-1 SFR. The electricity-sharing ratio between the 2 stages is 87.0% (SFR) to 13.0% (PWR) for a TRU inventory ratio (the mass of TRU in the discharge fuel divided by the mass of TRU in the fresh fuel) of 1.06. A sensitivity study indicated that by increasing the TRU inventory ratio to 1.13, The electricity generation fraction of stage-2 PWR is increased to 28.9%. The two-stage fuel cycle system considered in this study was found to provide a high uranium utilization (>80%). (authors)« less

Yield of H2O2 in Gas-Liquid Phase with Pulsed DBD

NASA Astrophysics Data System (ADS)

Jiang, Song; Wen, Yiyong; Liu, Kefu

2014-01-01

Electric discharge in water can generate a large number of oxidants such as ozone, hydrogen peroxide and hydroxyl radicals. In this paper, a non-thermal plasma processing system was established by means of pulsed dielectric barrier discharge in gas-liquid phase. The electrodes of discharge reactor were staggered. The yield of H2O2 was enhanced after discharge. The effects of discharge time, discharge voltage, frequency, initial pH value, and feed gas were investigated. The concentration of hydrogen peroxide and ozone was measured after discharge. The experimental results were fully analyzed. The chemical reaction equations in water were given as much as possible. At last, the water containing Rhodamine B was tested in this system. The degradation rate came to 94.22% in 30 min.

The effect of the electric wind on the spatial distribution of chemical species in the positive corona discharge

NASA Astrophysics Data System (ADS)

Yanallah, K.; Pontiga, F.; Bouazza, M. R.; Chen, J. H.

2017-08-01

The electrohydrodynamic air flow generated by a positive corona discharge, and its effect on the spatial distribution of chemical species within a wire-plate corona reactor, have been numerically simulated. The computational model is based on the solutions of the Navier-Stokes equation and the continuity equation of each chemical species generated by the electrical discharge. A simplified analytical expression of the electric force density, which only requires the current density as the input parameter, has been used in the Navier-Stokes equation to obtain the velocity field. For the solution of the continuity equations, a plasma chemistry model that includes the most important reactions between electrons, atoms and molecules in air has been used. Similar to the electric force, the electron density distribution has been approximated by using a semi-analytical expression appropriate for the electrode geometry. The results of the study show that the spatial distribution of chemical species can be very different, and depends on the interplay between the electrohydrodynamic flow, the chemical kinetics of the species and its characteristic lifetime.

Spent nuclear fuel discharges from US reactors 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-05-05

This report provides current statistical data on every fuel assembly irradiated in commercial nuclear reactors operating in the United States. It also provides data on the current inventories and storage capacities of those reactors to a wide audience, including Congress, Federal and State agencies, the nuclear and electric industries and the general public. It uses data from the mandatory, ``Nuclear Fuel Data`` survey, Form RW-859 for 1992 and historical data collected by the Energy Information Administration (EIA) on previous Form RW-859 surveys. The report was prepared by the EIA under a Memorandum of Understanding with the Office of Civilian Radioactivemore » Waste Management.« less

Nitrogen removal from purified swine wastewater using biogas by semi-partitioned reactor.

PubMed

Waki, Miyoko; Yokoyama, Hiroshi; Ogino, Akifumi; Suzuki, Kazuyoshi; Tanaka, Yasuo

2008-09-01

Nitrate and ammonium removal from purified swine wastewater using biogas and air was investigated in continuous reactor operation. A novel type of reactor, a semi-partitioned reactor (SPR), which enables a biological reaction using methane and oxygen in the water phase and discharges these unused gases separately, was operated with a varying gas supply rate. Successful removal of NO(3)(-) and NH(4)(+) was observed when biogas and air of 1L/min was supplied to an SPR of 9L water phase with a NO(2,3)(-)-N and NH(4)(+)-N removal rate of 0.10 g/L/day and 0.060 g/L/day, respectively. The original biogas contained an average of 77.2% methane, and the discharged biogas from the SPR contained an average of 76.9% of unused methane that was useable for energy like heat or electricity production. Methane was contained in the discharged air from the SPR at an average of 2.1%. When gas supply rates were raised to 2L/min and the nitrogen load was increased, NO(3)(-) concentration was decreased, but NO(2)(-) accumulated in the reactor and the NO(2,3)(-)-N and NH(4)(+)-N removal activity declined. To recover the activity, lowering of the nitrogen load and the gas supply rate was needed. This study shows that the SPR enables nitrogen removal from purified swine wastewater using biogas under limited gas supply condition.

Degradation of the chlorophenoxyacetic herbicide 2,4-D by plasma-ozonation system.

PubMed

Bradu, C; Magureanu, M; Parvulescu, V I

2017-08-15

A novel advanced oxidation process based on the combination of ozonation with non-thermal plasma generated in a pulsed corona discharge was developed for the oxidative degradation of recalcitrant organic pollutants in water. The pulsed corona discharge in contact with liquid, operated in oxygen, produced 3.5mgL -1 ozone, which was subsequently introduced in the ozonation reactor. The solution to be treated was continuously circulated between the plasma reactor and the ozonation reactor. The system was tested for the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) and considerably improved performance as compared to ozonation alone, both with respect to the removal of the target compound and to mineralization. The apparent reaction rate constant for 2,4-D removal was 0.195min -1 , more than two times higher than the value obtained in ozonation experiments. The mineralization reached more than 90% after 60min treatment and the chlorine balance confirms the absence of quantifiable amounts of chlorinated by-products. The energy efficiency was considerably enhanced by shortening the duration of the discharge pulses, which opens the way for further optimization of the electrical circuit design. Copyright © 2017 Elsevier B.V. All rights reserved.

Discharge Characteristics of Series Surface/Packed-Bed Discharge Reactor Diven by Bipolar Pulsed Power

NASA Astrophysics Data System (ADS)

Hu, Jian; Jiang, Nan; Li, Jie; Shang, Kefeng; Lu, Na; Wu, Yan; Mizuno, Akira

2016-03-01

The discharge characteristics of the series surface/packed-bed discharge (SSPBD) reactor driven by bipolar pulse power were systemically investigated in this study. In order to evaluate the advantages of the SSPBD reactor, it was compared with traditional surface discharge (SD) reactor and packed-bed discharge (PBD) reactor in terms of the discharge voltage, discharge current, and ozone formation. The SSPBD reactor exhibited a faster rising time and lower tail voltage than the SD and PBD reactors. The distribution of the active species generated in different discharge regions of the SSPBD reactor was analyzed by optical emission spectra and ozone analysis. It was found that the packed-bed discharge region (3.5 mg/L), rather than the surface discharge region (1.3 mg/L) in the SSPBD reactor played a more important role in ozone generation. The optical emission spectroscopy analysis indicated that more intense peaks of the active species (e.g. N2 and OI) in the optical emission spectra were observed in the packed-bed region. supported by National Natural Science Foundation of China (No. 51177007), the Joint Funds of National Natural Science Foundation of China (No. U1462105), and Dalian University of Technology Fundamental Research Fund of China (No. DUT15RC(3)030)

High-efficiency removal of NOx using dielectric barrier discharge nonthermal plasma with water as an outer electrode

NASA Astrophysics Data System (ADS)

Dan, ZHAO; Feng, YU; Amin, ZHOU; Cunhua, MA; Bin, DAI

2018-01-01

With the rapid increase in the number of cars and the development of industry, nitrogen oxide (NOx) emissions have become a serious and pressing problem. This work reports on the development of a water-cooled dielectric barrier discharge reactor for gaseous NOx removal at low temperature. The characteristics of the reactor are evaluated with and without packing of the reaction tube with 2 mm diameter dielectric beads composed of glass, ZnO, MnO2, ZrO2, or Fe2O3. It is found that the use of a water-cooled tube reduces the temperature, which stabilizes the reaction, and provides a much greater NO conversion efficiency (28.8%) than that obtained using quartz tube (14.1%) at a frequency of 8 kHz with an input voltage of 6.8 kV. Furthermore, under equivalent conditions, packing the reactor tube with glass beads greatly increases the NO conversion efficiency to 95.85%. This is because the dielectric beads alter the distribution of the electric field due to the influence of polarization at the glass bead surfaces, which ultimately enhances the plasma discharge intensity. The presence of the dielectric beads increases the gas residence time within the reactor. Experimental verification and a theoretical basis are provided for the industrial application of the proposed plasma NO removal process employing dielectric bead packing.

Analysis of a gas-liquid film plasma reactor for organic compound oxidation.

PubMed

Hsieh, Kevin; Wang, Huijuan; Locke, Bruce R

2016-11-05

A pulsed electrical discharge plasma formed in a tubular reactor with flowing argon carrier gas and a liquid water film was analyzed using methylene blue as a liquid phase hydroxyl radical scavenger and simultaneous measurements of hydrogen peroxide formation. The effects of liquid flow rate, liquid conductivity, concentration of dye, and the addition of ferrous ion on dye decoloration and degradation were determined. Higher liquid flow rates and concentrations of dye resulted in less decoloration percentages and hydrogen peroxide formation due to initial liquid conductivity effects and lower residence times in the reactor. The highest decoloration energy yield of dye found in these studies was 5.2g/kWh when using the higher liquid flow rate and adding the catalyst. The non-homogeneous nature of the plasma discharge favors the production of hydrogen peroxide in the plasma-liquid interface over the chemical oxidation of the organic in the bulk liquid phase and post-plasma reactions with the Fenton catalyst lead to complete utilization of the plasma-formed hydrogen peroxide. Copyright © 2016 Elsevier B.V. All rights reserved.

Filter for isotopic alteration of mercury vapor

DOEpatents

Grossman, M.W.; George, W.A.

1989-06-13

A filter is described for enriching the [sup 196]Hg content of mercury, including a reactor, a low pressure electric discharge lamp containing a fill of mercury and an inert gas. A filter is arranged concentrically around the lamp. The reactor is arranged around said filter, whereby radiation from said lamp passes through the filter and into said reactor. The lamp, the filter and the reactor are formed of quartz, and are transparent to ultraviolet light. The [sup 196]Hg concentration in the mercury fill is less than that which is present in naturally occurring mercury, that is, less than about 0.146 atomic weight percent. Hydrogen is also included in the fill and serves as a quenching gas in the filter, the hydrogen also serving to prevent disposition of a dark coating on the interior of the filter. 9 figs.

Filter for isotopic alteration of mercury vapor

DOEpatents

Grossman, Mark W.; George, William A.

1989-01-01

A filter for enriching the .sup.196 Hg content of mercury, including a reactor, a low pressure electric discharge lamp containing a fill of mercury and an inert gas. A filter is arranged concentrically around the lamp. The reactor is arranged around said filter, whereby radiation from said lamp passes through the filter and into said reactor. The lamp, the filter and the reactor are formed of quartz, and are transparent to ultraviolet light. The .sup.196 Hg concentration in the mercury fill is less than that which is present in naturally occurring mercury, that is less than about 0.146 atomic weight percent. Hydrogen is also included in the fill and serves as a quenching gas in the filter, the hydrogen also serving to prevent disposition of a dark coating on the interior of the filter.

Electric field induced needle-pulsed arc discharge carbon nanotube production apparatus: circuitry and mechanical design.

PubMed

Kia, Kaveh Kazemi; Bonabi, Fahimeh

2012-12-01

A simple and low cost apparatus is reported to produce multiwall carbon nanotubes and carbon nano-onions by a low power short pulsed arc discharge reactor. The electric circuitry and the mechanical design details and a micro-filtering assembly are described. The pulsed-plasma is generated and applied between two graphite electrodes. The pulse width is 0.3 μs. A strong dc electric field is established along side the electrodes. The repetitive discharges occur in less than 1 mm distance between a sharp tip graphite rod as anode, and a tubular graphite as cathode. A hydrocarbon vapor, as carbon source, is introduced through the graphite nozzle in the cathode assembly. The pressure of the chamber is controlled by a vacuum pump. A magnetic field, perpendicular to the plasma path, is provided. The results show that the synergetic use of a pulsed-current and a dc power supply enables us to synthesize carbon nanoparticles with short pulsed plasma. The simplicity and inexpensiveness of this plan is noticeable. Pulsed nature of plasma provides some extra degrees of freedom that make the production more controllable. Effects of some design parameters such as electric field, pulse frequency, and cathode shape are discussed. The products are examined using scanning probe microscopy techniques.

Electric field induced needle-pulsed arc discharge carbon nanotube production apparatus: Circuitry and mechanical design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kia, Kaveh Kazemi; Bonabi, Fahimeh

A simple and low cost apparatus is reported to produce multiwall carbon nanotubes and carbon nano-onions by a low power short pulsed arc discharge reactor. The electric circuitry and the mechanical design details and a micro-filtering assembly are described. The pulsed-plasma is generated and applied between two graphite electrodes. The pulse width is 0.3 {mu}s. A strong dc electric field is established along side the electrodes. The repetitive discharges occur in less than 1 mm distance between a sharp tip graphite rod as anode, and a tubular graphite as cathode. A hydrocarbon vapor, as carbon source, is introduced through themore » graphite nozzle in the cathode assembly. The pressure of the chamber is controlled by a vacuum pump. A magnetic field, perpendicular to the plasma path, is provided. The results show that the synergetic use of a pulsed-current and a dc power supply enables us to synthesize carbon nanoparticles with short pulsed plasma. The simplicity and inexpensiveness of this plan is noticeable. Pulsed nature of plasma provides some extra degrees of freedom that make the production more controllable. Effects of some design parameters such as electric field, pulse frequency, and cathode shape are discussed. The products are examined using scanning probe microscopy techniques.« less

Electric field induced needle-pulsed arc discharge carbon nanotube production apparatus: Circuitry and mechanical design

NASA Astrophysics Data System (ADS)

Kia, Kaveh Kazemi; Bonabi, Fahimeh

2012-12-01

A simple and low cost apparatus is reported to produce multiwall carbon nanotubes and carbon nano-onions by a low power short pulsed arc discharge reactor. The electric circuitry and the mechanical design details and a micro-filtering assembly are described. The pulsed-plasma is generated and applied between two graphite electrodes. The pulse width is 0.3 μs. A strong dc electric field is established along side the electrodes. The repetitive discharges occur in less than 1 mm distance between a sharp tip graphite rod as anode, and a tubular graphite as cathode. A hydrocarbon vapor, as carbon source, is introduced through the graphite nozzle in the cathode assembly. The pressure of the chamber is controlled by a vacuum pump. A magnetic field, perpendicular to the plasma path, is provided. The results show that the synergetic use of a pulsed-current and a dc power supply enables us to synthesize carbon nanoparticles with short pulsed plasma. The simplicity and inexpensiveness of this plan is noticeable. Pulsed nature of plasma provides some extra degrees of freedom that make the production more controllable. Effects of some design parameters such as electric field, pulse frequency, and cathode shape are discussed. The products are examined using scanning probe microscopy techniques.

Plasma spark discharge reactor and durable electrode

DOEpatents

Cho, Young I.; Cho, Daniel J.; Fridman, Alexander; Kim, Hyoungsup

2017-01-10

A plasma spark discharge reactor for treating water. The plasma spark discharge reactor comprises a HV electrode with a head and ground electrode that surrounds at least a portion of the HV electrode. A passage for gas may pass through the reactor to a location proximate to the head to provide controlled formation of gas bubbles in order to facilitate the plasma spark discharge in a liquid environment.

High effective heterogeneous plasma vortex reactor for production of heat energy and hydrogen

NASA Astrophysics Data System (ADS)

Belov, N. K.; Zavershinskii, I. P.; Klimov, A. I.; Molevich, N. E.; Porfiriev, D. P.; Tolkunov, B. N.

2018-03-01

This work is a continuation of our previous studies [1-10] of physical parameters and properties of a long-lived heterogeneous plasmoid (plasma formation with erosive nanoclusters) created by combined discharge in a high-speed swirl flow. Here interaction of metal nanoclusters with hydrogen atoms is studied in a plasma vortex reactor (PVR) with argon-water steam mixture. Metal nanoclusters were created by nickel cathode’s erosion at combined discharge on. Dissociated hydrogen atoms and ions were obtained in water steam by electric discharge. These hydrogen atoms and ions interacted with metal nanoclusters, which resulted in the creation of a stable plasmoid in a swirl gas flow. This plasmoid has been found to create intensive soft X-ray radiation. Plasma parameters of this plasmoid were measured by optical spectroscopy method. It has been obtained that there is a high non-equilibrium plasmoid: Te > TV >> TR. The measured coefficient of energy performance of this plasmoid is about COP = 2÷10. This extra power release in plasmoid is supposed to be connected with internal excited electrons. The obtained experimental results have proved our suggestion.

Core design of a direct-cycle, supercritical-water-cooled fast breeder reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jevremovic, T.; Oka, Yoshiaki; Koshizuka, Seiichi

1994-10-01

The conceptual design of a direct-cycle fast breeder reactor (FBR) core cooled by supercritical water is carried out as a step toward a low-cost FBR plant. The supercritical water does not exhibit change of phase. The turbines are directly driven by the core outlet coolant. In comparison with a boiling water reactor (BWR), the recirculation systems, steam separators, and dryers are eliminated. The reactor system is much simpler than the conventional steam-cooled FBRs, which adopted Loeffler boilers and complicated coolant loops for generating steam and separating it from water. Negative complete and partial coolant void reactivity are provided without muchmore » deterioration in the breeding performances by inserting thin zirconium-hydride layers between the seeds and blankets in a radially heterogeneous core. The net electric power is 1245 MW (electric). The estimated compound system doubling time is 25 yr. The discharge burnup is 77.7 GWd/t, and the refueling period is 15 months with a 73% load factor. The thermal efficiency is high (41.5%), an improvement of 24% relative to a BWR's. The pressure vessel is not thick at 30.3 cm.« less

Ozone generation by negative corona discharge: the effect of Joule heating

NASA Astrophysics Data System (ADS)

Yanallah, K.; Pontiga, F.; Fernández-Rueda, A.; Castellanos, A.; Belasri, A.

2008-10-01

Ozone generation in pure oxygen using a wire-to-cylinder corona discharge reactor is experimentally and numerically investigated. Ozone concentration is determined by means of direct UV spectroscopy and the effects of Joule heating and ozone decomposition on the electrodes are analysed for different discharge gaps. The numerical model combines the physical processes in the corona discharge with the chemistry of ozone formation and destruction. The chemical kinetics model and the electrical model are coupled through Poisson's equation, and the current-voltage (CV) characteristic measured in experiments is used as input data to the numerical simulation. The numerical model is able to predict the radial distributions of electrons, ions, atoms and molecules for each applied voltage of the CV characteristic. In particular, the evolution of ozone density inside the discharge cell has been investigated as a function of current intensity and applied voltage.

Electric discharge for treatment of trace contaminants

NASA Technical Reports Server (NTRS)

Flamm, D. L.; Wydeven, T. J. (Inventor)

1978-01-01

A radio frequency glow discharge reactor is described for removing trace oxidizable contaminants from an oxygen bearing atmosphere. The reaction chamber is defined by an inner metal electrode facing a dielectric backed by an outer conductive electrode. In one embodiment, a conductive liquid forms the conductor of an outer electrode and cools the dielectric. A resonator coupled to a variable radio frequency source generates the high voltages for creating a glow discharge in the chamber at a predetermined pressure whereby the trace contaminants are oxidized into a few simple non-toxic products that may be easily recovered. The corresponding process for removal of trace contaminants from an oxygen-bearing atmosphere with high efficiency independent of the concentration level is also disclosed.

Innovative approach for benzene degradation using hybrid surface/packed-bed discharge plasmas.

PubMed

Jiang, Nan; Lu, Na; Shang, Kefeng; Li, Jie; Wu, Yan

2013-09-03

An innovative plasma reactor, which generates hybrid surface/packed-bed discharge (HSPBD) plasmas, was employed for the degradation of benzene. The HSPBD reactor was found to display remarkably better benzene degradation, mineralization, and energy performance than surface or packed-bed discharge reactors alone. The degradation efficiency, CO2 selectivity, and energy yield in the HSPBD reactor were 21%, 11%, and 3.9 g kWh-1 higher, respectively, than in a surface discharge reactor and 30%, 21%, and 5.5 g kWh-1 higher, respectively, than in a packed-bed discharge reactor operated at 280 J L-1. Particularly, the benzene degradation in the HSPBD reactor exhibited an unambiguous synergistic enhancement rather than a simple additive effect using the surface discharge and packed-bed discharge reactors. Moreover, in the HSPBD reactor, the formation of byproducts, such as NO2, was suppressed, while O3 was promoted. The use of N2 as the carrier gas was found to be effective for benzene degradation because of the fast reaction rate of N2(A3∑u+) with benzene, and oxygen species derived from the dissociation of O2 were found to be significant in the mineralization process. Thus, the addition of O2 to N2 allows for efficient degradation of benzene, and the optimized amount of O2 was determined to be 3%.

Generation of ozone by pulsed corona discharge over water surface in hybrid gas liquid electrical discharge reactor

NASA Astrophysics Data System (ADS)

Lukes, Petr; Clupek, Martin; Babicky, Vaclav; Janda, Vaclav; Sunka, Pavel

2005-02-01

Ozone formation by a pulse positive corona discharge generated in the gas phase between a planar high voltage electrode made from reticulated vitreous carbon and a water surface with an immersed ground stainless steel plate electrode was investigated under various operating conditions. The effects of gas flow rate (0.5-3 litre min-1), discharge gap spacing (2.5-10 mm), applied input power (2-45 W) and gas composition (oxygen containing argon or nitrogen) on ozone production were determined. Ozone concentration increased with increasing power input and with increasing discharge gap. The production of ozone was significantly affected by the presence of water vapour formed through vaporization of water at the gas-liquid interface by the action of the gas phase discharge. The highest energy efficiency for ozone production was obtained using high voltage pulses of approximately 150 ns duration in Ar/O2 mixtures with the maximum efficiency (energy yield) of 23 g kW h-1 for 40% argon content.

Effect of frequency on the uniformity of symmetrical RF CCP discharges

NASA Astrophysics Data System (ADS)

Liu, Yue; Booth, Jean-Paul; Chabert, Pascal

2018-05-01

A 2D Cartesian electrostatic particle-in-cell/Monte Carlo collision (PIC/MCC) model presented previously (Liu et al 2018 Plasma Sources Sci. Technol. 27 025006) is used to investigate the effect of the driving frequency (over the range of 15–45 MHz) on the plasma uniformity in radio frequency (RF) capacitively coupled plasma (CCP) discharges in a geometrically symmetric reactor with a dielectric side wall in argon gas. The reactor size (12 cm electrode length, 2.5 cm gap) and driving frequency are sufficiently small that electromagnetic effects can be ignored. Previously, we showed (Liu et al 2018 Plasma Sources Sci. Technol. 27 025006) that for 15 MHz excitation, Ohmic heating of electrons by the electric field perpendicular to the electrodes is enhanced in a region in front of the dielectric side wall, leading to a maximum in electron density there. In this work we show that increasing the excitation frequency (at constant applied voltage amplitude) not only increases the overall electron heating and density but also causes a stronger, narrower peak in electron heating closer to the dielectric wall, improving the plasma uniformity along the electrodes. This heating peak comes both from enhanced perpendicular electron heating and from the appearance at high frequency of significant parallel heating. The latter is caused by the presence of a significant parallel-direction RF oscillating electric field in the corners. Whereas at the reactor center the sheaths oscillate perpendicularly to the electrodes, near the dielectric edge they move in and out of the corners and must be treated in two dimensions.

Time history of diesel particle deposition in cylindrical dielectric barrier discharge reactors

NASA Astrophysics Data System (ADS)

Talebizadeh, P.; Rahimzadeh, H.; Ahmadi, G.; Brown, R.; Inthavong, K.

2016-12-01

Non-thermal plasma (NTP) treatment reactors have recently been developed for elimination of diesel particulate matter for reducing both the mass and number concentration of particles. The role of the plasma itself is obscured by the phenomenon of particle deposition on the reactor surface. Therefore, in this study, the Lagrangian particle transport model is used to simulate the dispersion and deposition of nano-particles in the range of 5 to 500 nm in a NTP reactor in the absence of an electric field. A conventional cylindrical dielectric barrier discharge reactor is selected for the analysis. Brownian diffusion, gravity and Saffman lift forces were included in the simulations, and the deposition efficiencies of different sized diesel particles were studied. The results show that for the studied particle diameters, the effect of Saffman lift is negligible and gravity only affects the motion of particles with a diameter of 500 nm or larger. Time histories of particle transport and deposition were evaluated for one-time injection and a continuous (multiple-time) injection. The results show that the number of deposited particles for one-time injection is identical to the number of deposited particles for multiple-time injections when adjusted with the shift in time. Furthermore, the maximum number of escaped particles occurs at 0.045 s after the injection for all particle diameters. The presented results show that some particle reduction previously ascribed to plasma treatment has ignored contributions from the surface deposition.

Effects of water vapor on flue gas conditioning in the electric fields with corona discharge.

PubMed

Liqiang, Qi; Yajuan, Zhang

2013-07-15

Sulfur dioxide (SO2) removal via pulsed discharge nonthermal plasma in the absence of ammonia was investigated to determine how electrostatic precipitators (ESPs) can effectively collect particulate matter less than 2.5μm in diameter from flue gas. SO2 removal increased as water vapor concentration increased. In a wet-type plasma reactor, directing a gas-phase discharge plasma toward the water film surface significantly enhanced the liquid-phase oxidation of HSO3(-) to SO4(2-). Comparisons of various absorbents revealed that the hydroxyl radical is a key factor in plasma-induced liquid-phase reactions. The resistivity, size distribution, and cohesive force of fly ash at different water vapor contents were measured using a Bahco centrifuge, which is a dust electrical resistivity test instrument, as well as a cohesive force test apparatus developed by the researchers. When water vapor content increased by 5%, fly ash resistivity in flue gas decreased by approximately two orders of magnitude, adhesive force and size increased, and specific surface area decreased. Therefore, ESP efficiency increased. Copyright © 2013 Elsevier B.V. All rights reserved.

Hybrid plasmachemical reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lelevkin, V. M., E-mail: lelevkin44@mail.ru; Smirnova, Yu. G.; Tokarev, A. V.

2015-04-15

A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

Study and Control of Various Corona Modes in an Atmospheric Pressure Weakly Ionized Plasma Reactor Using a Current Sensor Characterized by a Broad Frequency Band

NASA Astrophysics Data System (ADS)

Islam, Rokibul; Pedrow, Patrick; Lekobou, William; Englund, Karl

2013-09-01

A broad band current sensor is being used to monitor the various phenomena (primary streamers, secondary streamers, back corona, etc.) associated with an atmospheric pressure needle-array-to-grounded-screen corona discharge. The reactor consists of a PVC tube and the needle array consists of nickel coated steel electrodes with radius of curvature about 50 μ . The grounded screen is made from stainless steel mesh and applied voltage has a frequency of 60 Hz with an RMS value ranging from 0 to 10 kV. The voltage sensor is a resistive divider and the current sensor is a viewing resistor with value 50 Ω. The feed gas stream is presently (argon + acetylene) or (argon + oxygen) with the argon acting as carrier gas and the acetylene and oxygen acting as precursor gases. Voltage and current are captured with a LeCroy 9350AL 500MHz oscilloscope and analyzed with Matlab using digital signal processing algorithms. The goals of the research are 1) to measure reactor electrical power on a real time basis; 2) to provide real time control of the applied voltage and thus avoid spark conditions; and 3) to identify the various corona modes present in the reactor. Processing of substrates takes place downstream from the grounded screen, outside of the harsh corona discharge environment.

[Diagnosis of electron energy and comparative effects of OH, O or O3 on NO oxidation in pulsed corona discharge].

PubMed

Xuan, Jian-yong; Luo, Zhong-yang; Zhao, Lei; Jiang, Jian-ping; Gao, Xiang

2012-05-01

The spectrum of excited N2 molecules and ions was measured by optical emission spectroscopy in pulsed corona discharge with a wire-to-plate reactor. The ratio of emission intensities emitted by the excited molecules and ions of N2 was compared with numerical simulation to determine average electron energies and electric field distributions. Within 2 cm distance from wire electrode in horizontal and vertical directions, electric field and average electron energies appear to be in the ranges of 11.05 19.6 MV x m(-1) and 10.10-13.92 eV respectively; as the distance increases, average electron energies and electric field show a similar trend: first decrease and then increase. Chemically active species, such as OH, O and O3, can be generated through the energetic electron collisions with H2O and O2 directly or indirectly. For the NO oxidation, there is no coexistence of NO and O3, whereas there is a coexistence of NO and OH. NO is oxidized by O3 or O more efficiently than by OH radical.

[Study of emission spectroscopy of OH radicals in pulsed corona discharge].

PubMed

Wei, Bo; Luo, Zhong-Yang; Xu, Fei; Zhao, Lei; Gao, Xiang; Cen, Ke-Fa

2010-02-01

In the present paper, OH radicals generated by pulsed corona discharge in humidified air, N2 and Ar in a needle-plate reactor were measured by emission spectra. With the analysis of the emission spectra, the influence of pulse peak voltage and frequency on OH radical generation was investigated in the three kinds of background gases. The influence of the gas humidity on the generation and the distribution of OH radicals in the electric field was also discussed in detail. The authors studied the influence of the gas humidity on the generation of OH radicals in the electric field by the control of accurate change in humidity, and we also studied the distribution of OH radicals in the electric field in different background gases including humidified air, N2 and Ar by the accurate change in scales. The experiment shows that the output of OH radicals grows as the pulse peak voltage and frequency grow, but the influence of gas humidity on the process of generating OH radicals by pulsed corona discharge depends on the discharge background. The rules of the generation change when the background gases change. As the humidity in the background gases grows, the amount of OH radicals grows in the air, but it grows at first and decreases at last in N2, while it decreases at first and grows at last in Ar. The distribution of OH radical shows a trend of decreasing from the needle-electrode to its circumambience.

Decomposition of atrazine traces in water by combination of non-thermal electrical discharge and adsorption on nanofiber membrane.

PubMed

Vanraes, Patrick; Willems, Gert; Daels, Nele; Van Hulle, Stijn W H; De Clerck, Karen; Surmont, Pieter; Lynen, Frederic; Vandamme, Jeroen; Van Durme, Jim; Nikiforov, Anton; Leys, Christophe

2015-04-01

In recent decades, several types of persistent substances are detected in the aquatic environment at very low concentrations. Unfortunately, conventional water treatment processes are not able to remove these micropollutants. As such, advanced treatment methods are required to meet both current and anticipated maximally allowed concentrations. Plasma discharge in contact with water is a promising new technology, since it produces a wide spectrum of oxidizing species. In this study, a new type of reactor is tested, in which decomposition by atmospheric pulsed direct barrier discharge (pDBD) plasma is combined with micropollutant adsorption on a nanofiber polyamide membrane. Atrazine is chosen as model micropollutant with an initial concentration of 30 μg/L. While the H2O2 and O3 production in the reactor is not influenced by the presence of the membrane, there is a significant increase in atrazine decomposition when the membrane is added. With membrane, 85% atrazine removal can be obtained in comparison to only 61% removal without membrane, at the same experimental parameters. The by-products of atrazine decomposition identified by HPLC-MS are deethylatrazine and ammelide. Formation of these by-products is more pronounced when the membrane is added. These results indicate the synergetic effect of plasma discharge and pollutant adsorption, which is attractive for future applications of water treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

REGULATOR FOR CALUTRON ION SOURCE

DOEpatents

Miller, B.F.

1958-09-01

Improvements are described in electric discharge devices and circuits for a calutron and, more specifically, presents an arc discharge regulator circuit for the ion source of the calatron. In general, the source comprises a filament which bombards a cathode with electrons, a griid control electrode between the filament and the cathode, and an anode electrode. The control electrode has a DC potential which is varied in response to changes in the anode current flow by means of a saturable reactor installed in its power supply energizing line having the anode current flowing through its control winding. In this manner the bombardment current to the cathode may be decreased when the anode current increases beyond a predetermined level.

Online residence time distribution measurement of thermochemical biomass pretreatment reactors

DOE PAGES

Sievers, David A.; Kuhn, Erik M.; Stickel, Jonathan J.; ...

2015-11-03

Residence time is a critical parameter that strongly affects the product profile and overall yield achieved from thermochemical pretreatment of lignocellulosic biomass during production of liquid transportation fuels. The residence time distribution (RTD) is one important measure of reactor performance and provides a metric to use when evaluating changes in reactor design and operating parameters. An inexpensive and rapid RTD measurement technique was developed to measure the residence time characteristics in biomass pretreatment reactors and similar equipment processing wet-granular slurries. Sodium chloride was pulsed into the feed entering a 600 kg/d pilot-scale reactor operated at various conditions, and aqueous saltmore » concentration was measured in the discharge using specially fabricated electrical conductivity instrumentation. This online conductivity method was superior in both measurement accuracy and resource requirements compared to offline analysis. Experimentally measured mean residence time values were longer than estimated by simple calculation and screw speed and throughput rate were investigated as contributing factors. In conclusion, a semi-empirical model was developed to predict the mean residence time as a function of operating parameters and enabled improved agreement.« less

Characterization of a dielectric barrier discharge in contact with liquid and producing a plasma activated water

NASA Astrophysics Data System (ADS)

Neretti, G.; Taglioli, M.; Colonna, G.; Borghi, C. A.

2017-01-01

In this work a low-temperature plasma source for the generation of plasma activated water (PAW) is developed and characterized. The plasma reactor was operated by means of an atmospheric-pressure air dielectric barrier discharge (DBD). The plasma generated is in contact with the water surface and is able to chemically activate the liquid medium. Electrodes were supplied by both sinusoidal and nanosecond-pulsed voltage waveforms. Treatment times were varied from 2 to 12 min to increase the energy dose released to the water by the DBD plasma. The physics of the discharge was studied by means of electrical, spectroscopic and imaging diagnostics. The interaction between the plasma and the liquid was investigated as well. Temperature and composition of the treated water were detected. Images of the discharges showed a filamentary behaviour in the sinusoidal case and a more homogeneous behaviour in the nanosecond-pulsed one. The images and the electrical measurements allowed to evaluate an average electron number density of about 4  ×  1019 and 6  ×  1017 m-3 for the sinusoidal and nanosecond-pulsed discharges respectively. Electron temperatures in the range of 2.1÷2.6 eV were measured by using spectroscopic diagnostics. Rotational temperatures in the range of 318-475 K were estimated by fitting synthetic spectra with the measured ones. Water temperature and pH level did not change significantly after the exposure to the DBD plasma. The production of ozone and hydrogen peroxide within the water was enhanced by increasing the plasma treatment time and the energy dose. Numerical simulations of the nanosecond-pulsed discharge were performed by using a self-consistent coupling of state-to-state kinetics of the air mixture with the Boltzmann equation of free electron kinetics. Temporal evolution of the electron energy distribution function shows departure from the Maxwellian distribution especially during the afterglow phase of the discharge. When limited deviations from Maxwellian distribution were observed, calculated electron temperature is in good agreement with the one measured by means of spectroscopic diagnostics. Computed temporal evolution of the energy delivered to the discharge is comparable with the one obtained from electrical measurements. The electrical discharges supplied by both voltage waveforms produce plasma activated water with negligible thermal effects and pH variations.

DISCHARGE DEVICE FOR RADIOACTIVE MATERIAL

DOEpatents

Ohlinger, L.A.

1958-09-23

A device is described fur unloading bodies of fissionable material from a neutronic reactor. It is comprised essentially of a wheeled flat car having a receptacle therein containing a liquid coolant fur receiving and cooling the fuel elements as they are discharged from the reactor, and a reciprocating plunger fur supporting the fuel element during discharge thereof prior to its being dropped into the coolant. The flat car is adapted to travel along the face of the reactor adjacent the discharge ends of the coolant tubes.

Generation and Reduction of NOx on Air-Fed Ozonizers

NASA Astrophysics Data System (ADS)

Ehara, Yoshiyasu; Amemiya, Yusuke; Yamamoto, Toshiaki

A generation and reduction of NOx on air-fed ozonizers using a ferroelectric packed bed reactor have been experimentally investigated. The reactors packed with CaTiO3, SrTiO3 and BaTiO3 pellets are examined for ozone generation. An ac voltage is applied to the reactor to generate partial discharge. Ozone concentration and the different nitrogen oxides at downstream of the packed bed reactor were measured with UV absorption ozone monitor and a Fourier transform infrared spectroscope respectively. The dielectric constant of packed ferroelectric pellets influences the discharge characteristic, ozone and NOx generations are varied by the dielectric constant value. Focusing on a discharge pulse current and maximum discharge magnitude, the ferroelectric packed bed plasma reactors have been evaluated on nitrogen oxide and ozone generated concentrations.

A Transport Model for Non-Local Heating of Electrons in ICP Reactors

NASA Technical Reports Server (NTRS)

Chang, C. H.; Bose, Deepak; Arnold, James O. (Technical Monitor)

1998-01-01

A new model has been developed for non-local heating of electrons in ICP reactors, based on a hydrodynamic approach. The model has been derived using the electron momentum conservation in azimuthal direction with electromagnetic and frictional forces respectively as driving force and damper of harmonic oscillatory motion of electrons. The resulting transport equations include the convection of azimuthal electron momentum in radial and axial directions, thereby accounting for the non-local effects. The azimuthal velocity of electrons and the resulting electrical current are coupled to the Maxwell's relations, thus forming a self-consistent model for non-local heating. This model is being implemented along with a set of Navier-Stokes equations for plasma dynamics and gas flow to simulate low-pressure (few mTorr's) ICP discharges. Characteristics of nitrogen plasma in a TCP 300mm etch reactor is being studied. The results will be compared against the available Langmuir probe measurements.

Ozone generation by negative direct current corona discharges in dry air fed coaxial wire-cylinder reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yehia, Ashraf; Mizuno, Akira

An analytical study was made in this paper for calculating the ozone generation by negative dc corona discharges. The corona discharges were formed in a coaxial wire-cylinder reactor. The reactor was fed by dry air flowing with constant rates at atmospheric pressure and room temperature, and stressed by a negative dc voltage. The current-voltage characteristics of the negative dc corona discharges formed inside the reactor were measured in parallel with concentration of the generated ozone under different operating conditions. An empirical equation was derived from the experimental results for calculating the ozone concentration generated inside the reactor. The results, thatmore » have been recalculated by using the derived equation, have agreed with the experimental results over the whole range of the investigated parameters, except in the saturation range for the ozone concentration. Therefore, the derived equation represents a suitable criterion for expecting the ozone concentration generated by negative dc corona discharges in dry air fed coaxial wire-cylinder reactors under any operating conditions in range of the investigated parameters.« less

Determining the microwave coupling and operational efficiencies of a microwave plasma assisted chemical vapor deposition reactor under high pressure diamond synthesis operating conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nad, Shreya; Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824; Gu, Yajun

2015-07-15

The microwave coupling efficiency of the 2.45 GHz, microwave plasma assisted diamond synthesis process is investigated by experimentally measuring the performance of a specific single mode excited, internally tuned microwave plasma reactor. Plasma reactor coupling efficiencies (η) > 90% are achieved over the entire 100–260 Torr pressure range and 1.5–2.4 kW input power diamond synthesis regime. When operating at a specific experimental operating condition, small additional internal tuning adjustments can be made to achieve η > 98%. When the plasma reactor has low empty cavity losses, i.e., the empty cavity quality factor is >1500, then overall microwave discharge coupling efficienciesmore » (η{sub coup}) of >94% can be achieved. A large, safe, and efficient experimental operating regime is identified. Both substrate hot spots and the formation of microwave plasmoids are eliminated when operating within this regime. This investigation suggests that both the reactor design and the reactor process operation must be considered when attempting to lower diamond synthesis electrical energy costs while still enabling a very versatile and flexible operation performance.« less

Methods for natural gas and heavy hydrocarbon co-conversion

DOEpatents

Kong, Peter C [Idaho Falls, ID; Nelson, Lee O [Idaho Falls, ID; Detering, Brent A [Idaho Falls, ID

2009-02-24

A reactor for reactive co-conversion of heavy hydrocarbons and hydrocarbon gases and includes a dielectric barrier discharge plasma cell having a pair of electrodes separated by a dielectric material and passageway therebetween. An inlet is provided for feeding heavy hydrocarbons and other reactive materials to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a variety of light sources for providing ultraviolet light within the discharge plasma cell. Methods for upgrading heavy hydrocarbons are also disclosed.

Nonthermal plasma systems and methods for natural gas and heavy hydrocarbon co-conversion

DOEpatents

Kong, Peter C.; Nelson, Lee O.; Detering, Brent A.

2005-05-24

A reactor for reactive co-conversion of heavy hydrocarbons and hydrocarbon gases and includes a dielectric barrier discharge plasma cell having a pair of electrodes separated by a dielectric material and passageway therebetween. An inlet is provided for feeding heavy hydrocarbons and other reactive materials to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a variety of light sources for providing ultraviolet light within the discharge plasma cell. Methods for upgrading heavy hydrocarbons are also disclosed.

Application of Bioelectrochemical Process (BES) for Electricity Generation and Sustainable Wastewater Treatment

NASA Astrophysics Data System (ADS)

Kim, Jung Rae

Bioelectrochemical system such as microbial fuel cells (MFCs) and microbial electrolysis cell are an emerging technology which converts biodegradable organic matter to electrical energy or hydrogen using a biofilm on the electrode as the biocatalyst. It has recently been shown that waste-to-energy technology based on MFC can treat organic contaminant in domestic or industrial wastewater and simultaneously produce electricity. The maximum power density increased up to 1kW/m3 based on reactor volume. Bioelectrochemical systems may reduce the energy consumption for wastewater treatment by replacing energy intensive aeration of present treatment systems, while generate electrical energy from waste. In addition, the biomass production in MFCs has been reported to be 10-50% of conventional wastewater treatment, leading to reduce environmental impact and disposal costs. Various electrochemically active bacteria metabolize biodegradable organic compounds then discharge electrons to an extracellular electron acceptor for bacterial respiration. These bacteria also transfer electrons to electrodes by direct electron transfer, electron mediators or shuttles, and electrically conductive nanowires. Investigation of bacterial electron transport mechanisms may improve understanding of the biomaterial involved and metabolic pathways as well as improving power from MFCs. Biofuel cell systems require interdisciplinary research ranging from electrochemistry, microbiology, material science and surface chemistry to engineering such as reactor design, operation and modelling. Collaboration within each study and integration of systems might increase the performance and feasibility of BES process for sustainable energy.

Low-cost solar array project task 1: Silicon material. Gaseous melt replenishment system

NASA Technical Reports Server (NTRS)

Jewett, D. N.; Bates, H. E.; Hill, D. M.

1980-01-01

The operation of a silicon production technique was demonstrated. The essentials of the method comprise chemical vapor deposition of silicon, by hydrogen reduction of chlorosilanes, on the inside of a quartz reaction vessel having large internal surface area. The system was designed to allow successive deposition-melting cycles, with silicon removal being accomplished by discharging the molten silicon. The liquid product would be suitable for transfer to a crystal growth process, casting into solid form, or production of shots. A scaled-down prototype reactor demonstrated single pass conversion efficiency of 20 percent and deposition rates and energy consumption better than conventional Siemens reactors, via deposition rates of 365 microns/hr. and electrical consumption of 35 Kwhr/kg of silicon produced.

Synthesis and investigation of reaction mechanisms of diamondoids obtained by dielectric barrier discharge microplasma reactors operated in adamantane - argon - methane - hydrogen mixtures at atmospheric pressure

NASA Astrophysics Data System (ADS)

Stauss, Sven; Ishii, Chikako; Pai, David Z.; Terashima, Kazuo

2013-09-01

Diamondoids, sp3 hybridized molecules consisting of a cage-like carbon framework with hydrogen terminations, hold promise for many applications: biotechnology, medicine, and opto- and nanoelectronics. So far, diamondoids consisting of more than four cage units have been synthesized by electric discharge and pulsed laser plasmas in supercritical fluids, but the generation of plasmas in high-pressure media is not straightforward. Here we present an alternative, continuous flow process, where diamondoids are synthesized by dielectric barrier discharges inside microreactors. The plasmas were generated at peak-to-peak voltages of 3 - 4 kV at a frequency of 10 kHz, in Ar (96 - 100%-vol) - methane (0 - 4%-vol) - hydrogen (0 - 4%-vol) mixtures, at atmospheric pressure and flow rates of 2 - 20 sccm. As a precursor we used the first diamondoid, adamantane, whose density was controlled by adjusting the reactor temperature in the range from 293 to 323 K. Gas chromatography - mass spectrometry analysis indicated the synthesis of the second diamondoid, diamantane, and the presence of alkylated adamantane derivatives suggests a stepwise reaction mechanism. We will also discuss the influence of the plasma gas composition and precursor density on the diamondoid synthesis. Grant No. 21110002, MEXT, Japan.

Ozone production using dielectric barrier discharge in oxygen and carbon dioxide

NASA Astrophysics Data System (ADS)

Pontiga, Francisco; Abidat, Roukia; Moreno, Helena; Agustín, Fernández-Rueda; Rebiaï, Saida

2015-09-01

The generation of ozone in oxygen and carbon dioxide using a planar dielectric barrier discharge (DBD) has been experimentally investigated. The DBD reactor was operated at moderate voltages (4.2 to 5.6 kV) and frequencies (50 to 500 Hz) and the gas flow rate was varied in the range 50 to 200 cm3/min. The averaged consumed power (<1 W) was evaluated using a monitor capacitor of known capacitance (1 μF). The effluent gas from the DBD reactor was diverted to a gas cell situated inside the sample compartment of a UV spectrophotometer. Therefore, ozone concentration was determined from the measurement of absorbance using Beer-Lambert law. The results have shown that ozone concentration in oxygen grows very linearly with the input power. In contrast, the production of ozone in carbon dioxide is less regular, which may be due to the deposition of a thin layer over the stainless steel electrode during the application of the electrical discharge. Moreover, the rate of ozone production with the injected energy density was found to be 500 times weaker in carbon dioxide than in pure oxygen. This work was supported by the Spanish Government Agency ``Ministerio de Ciencia e Innovación'' under Contract No. FIS2011-25161.

Influence of power supply on the generation of ozone and degradation of phenol in a surface discharge reactor

NASA Astrophysics Data System (ADS)

Zhao, Yan; Shang, Kefeng; Duan, Lijuan; Li, Yue; An, Jiutao; Zhang, Chunyang; Lu, Na; Li, Jie; Wu, Yan

2013-03-01

A surface Dielectric Barrier Discharge (DBD) reactor was utilized to degrade phenol in water. Different power supplies applied to the DBD reactor affect the discharge modes, the formation of chemically active species and thus the removal efficiency of pollutants. It is thus important to select an optimized power supply for the DBD reactor. In this paper, the influence of the types of power supplies including alternate current (AC) and bipolar pulsed power supply on the ozone generation in a surface discharge reactor was measured. It was found that compared with bipolar pulsed power supply, higher energy efficiency of O3 generation was obtained when DBD reactor was supplied with 50Hz AC power supply. The highest O3 generation was approximate 4 mg kJ-1 moreover, COD removal efficiency of phenol wastewater reached 52.3% after 3 h treatment under an AC peak voltage of 2.6 kV.

Numerical simulations of dielectric barrier discharges

NASA Astrophysics Data System (ADS)

Martens, Tom

A plasma or gas discharge is a state of matter which can be described as a gas containing ionized atoms and molecules. This ionized gas exhibits a collective behaviour under influence of an electric or a magnetic field, which are responsible for unique properties which make all new kinds of technology possible. The most important motivation behind the research is finding more efficient ways to produce a low-temperature plasma. In order to achieve this different reactor geometries are studied, it is investigated which is the most suitable power source and the influence of small contaminations of the operating gas is assessed. The studied plasmas are mainly operated at atmospheric pressure. Working at this pressure is cheaper and it makes it possible to develop assembly line treatments. Such plasmas are most easily generated in very small geometries, although energetic derailment of the discharge becomes a substantial risk. This is avoided when the electrodes are electrically insulated. In such setup the insulators accumulate charges which compensate the governing electric field, which keeps the energy transfer to the discharge limited. By studying these discharges using computer models, the changes in the plasma chemistry in time and also under the influence of different levels of impurities were characterized in great detail. Moreover, it was also determined how these chemical changes determine the electrical characteristics of the plasma. Finally, the insights in the charging and discharging effects of the insulators were used to make predictions on which type of power source is the most efficient in using the potential energy stored on the insulator surface to generate the plasma. The most important conclusions are that molecular impurities of the order of only one part per million already dominate the ionic particle distributions in the plasma and that a well-designed alteration in the applied voltage profile leads to a plasma generation with a more than three times more efficient use of consumed energy. This way the research contributes to the insight in the operation and forms the base for new and improved applications and technologies.

Pulsed Power Discharges in Water

NASA Astrophysics Data System (ADS)

Kratel, Axel Wolf Hendrik

An Electrohydraulic Discharge Process (EHD) for the treatment of hazardous chemical wastes in water has been developed. Liquid waste in a 4 L EHD reactor is directly exposed to high-energy pulsed electrical discharges between two submerged electrodes. The high-temperature (> 14,000 K) plasma channel created by an EHD discharge emits ultraviolet radiation, and produces an intense shock wave as it expands against the surrounding water. A simulation of the EHD process is presented along with experimental results. The simulation assumes a uniform plasma channel with a plasma that obeys the ideal gas law and the Spitzer conductivity law. The results agree with previously published data. The simulation is used to predict the total energy efficiency, energy partitioning, maximum plasma channel temperature and pressure for the Caltech Pulsed Power Facility (CPPF). The simulation shows that capacitance, initial voltage and gap length can be used to control the efficiency of the discharge. The oxidative degradation of 4-chlorophenol (4 -CP), 3,4-dichloroaniline (3,4-DCA), and 2,4,6 trinitrotoluene (TNT) in an EHD reactor was explored. The initial rates of degradation for the three substrates are described by a first-order rate equation, where k_{ it 0/} is the zero-order rate constant that accounts for direct photolysis; and k_ {it 1/} is the first-order term that accounts for oxidation in the plasma channel region. For 4-CP in the 4.0 L reactor, the values of these two rate constants are k_{it 0/} = 0.73 +/- 0.08 mu M, and k_{ it 1/} =(9.4 +/- 1.4) times 10^{-4}. For a 200 mu M 4-CP solution this corresponds to an overall intrinsic zero-order rate constant of 0.022 M s^{it -1/} , and a G-value of 4.45 times 10^{-3}. Ozone increases the rate and extent of degradation of the substrates in the EHD reactor. Combined EHD/ozone treatment of a 160 mu M TNT solution resulted in the complete degradation of TNT, and a 34% reduction of the total organic carbon (TOC). The intrinsic initial rate constant of TNT degradation was 0.024 M s^{it -1/} . The results of these experiments demonstrate the potential application of the EHD process for the treatment of hazardous wastes.

Apparatus and methods for direct conversion of gaseous hydrocarbons to liquids

DOEpatents

Kong, Peter C.; Lessing, Paul A.

2006-04-25

A chemical reactor for direct conversion of hydrocarbons includes a dielectric barrier discharge plasma cell and a solid oxide electrochemical cell in fluid communication therewith. The discharge plasma cell comprises a pair of electrodes separated by a dielectric material and passageway therebetween. The electrochemical cell comprises a mixed-conducting solid oxide electrolyte membrane tube positioned between a porous cathode and a porous anode, and a gas inlet tube for feeding oxygen containing gas to the porous cathode. An inlet is provided for feeding hydrocarbons to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a light source for directing ultraviolet light into the discharge plasma cell and the electrochemical cell.

Characteristics of ultraviolet light and radicals formed by pulsed discharge in water

NASA Astrophysics Data System (ADS)

Sun, Bing; Kunitomo, Shinta; Igarashi, Chiaki

2006-09-01

In this investigation, the ultraviolet light characteristics and OH radical properties produced by a pulsed discharge in water were studied. For the plate-rod reactor, it was found that the ultraviolet light energy has a 3.2% total energy injected into the reactor. The ultraviolet light changed with the peak voltage and electrode distance. UV characteristics in tap water and the distilled water are given. The intensity of the OH radicals was the highest for the 40 mm electrode distance reactor. In addition, the properties of hydrogen peroxide and ozone were also studied under arc discharge conditions. It was found that the OH radicals were in the ground state and the excited state when a pulsed arc discharge was used. The ozone was produced by the arc discharge even if the oxygen gas is not bubbled into the reactor. The ozone concentration produces a maximum value with treatment time.

Method for direct conversion of gaseous hydrocarbons to liquids

DOEpatents

Kong, Peter C.; Lessing, Paul A.

2006-03-07

A chemical reactor for direct conversion of hydrocarbons includes a dielectric barrier discharge plasma cell and a solid oxide electrochemical cell in fluid communication therewith. The discharge plasma cell comprises a pair of electrodes separated by a dielectric material and passageway therebetween. The electrochemical cell comprises a mixed-conducting solid oxide electrolyte membrane tube positioned between a porous cathode and a porous anode, and a gas inlet tube for feeding oxygen containing gas to the porous cathode. An inlet is provided for feeding hydrocarbons to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a light source for directing ultraviolet light into the discharge plasma cell and the electrochemical cell.

Initiation of long, free-standing z discharges by CO2 laser gas heating

NASA Astrophysics Data System (ADS)

Niemann, C.; Tauschwitz, A.; Penache, D.; Neff, S.; Knobloch, R.; Birkner, R.; Presura, R.; Hoffmann, D. H. H.; Yu, S. S.; Sharp, W. M.

2002-01-01

High current discharge channels can neutralize both current and space charge of very intense ion beams. Therefore, they are considered an interesting solution for final focus and beam transport in a heavy ion beam fusion reactor. At the Gesellschaft für Schwerionenforschung accelerator facility, 50 cm long, free-standing discharge channels were created in a 60 cm diameter metallic chamber. Discharges with currents of 45 kA in 2 to 25 mbar ammonia (NH3) gas are initiated by a CO2 laser pulse along the channel axis before the capacitor bank is triggered. Resonant absorption of the laser, tuned to the v2 vibration of the ammonia molecule, causes strong gas heating. Subsequent expansion and rarefaction of the gas prepare the conditions for a stable discharge to fulfill the requirements for ion beam transport. The influence of an electric prepulse on the high current discharge was investigated. This article describes the laser-gas interaction and the discharge initiation mechanism. We found that channels are magnetohydrodynamic stable up to currents of 45 kA, measured by fast shutter and streak imaging techniques. The rarefaction of the laser heated gas is studied by means of a one-dimensional Lagrangian fluid code (CYCLOPS) and is identified as the dominant initiation mechanism of the discharge.

Georgia Tech Studies of Sub-Critical Advanced Burner Reactors with a D-T Fusion Tokamak Neutron Source for the Transmutation of Spent Nuclear Fuel

NASA Astrophysics Data System (ADS)

Stacey, W. M.

2009-09-01

The possibility that a tokamak D-T fusion neutron source, based on ITER physics and technology, could be used to drive sub-critical, fast-spectrum nuclear reactors fueled with the transuranics (TRU) in spent nuclear fuel discharged from conventional nuclear reactors has been investigated at Georgia Tech in a series of studies which are summarized in this paper. It is found that sub-critical operation of such fast transmutation reactors is advantageous in allowing longer fuel residence time, hence greater TRU burnup between fuel reprocessing stages, and in allowing higher TRU loading without compromising safety, relative to what could be achieved in a similar critical transmutation reactor. The required plasma and fusion technology operating parameter range of the fusion neutron source is generally within the anticipated operational range of ITER. The implications of these results for fusion development policy, if they hold up under more extensive and detailed analysis, is that a D-T fusion tokamak neutron source for a sub-critical transmutation reactor, built on the basis of the ITER operating experience, could possibly be a logical next step after ITER on the path to fusion electrical power reactors. At the same time, such an application would allow fusion to contribute to meeting the nation's energy needs at an earlier stage by helping to close the fission reactor nuclear fuel cycle.

Comparison of electrical and optical characteristics in gas-phase and gas-liquid phase discharges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qazi, H. I. A.; Li, He-Ping, E-mail: liheping@tsinghua.edu.cn; Zhang, Xiao-Fei

This paper presents an AC-excited argon discharge generated using a gas-liquid (two-phase) hybrid plasma reactor, which mainly consists of a powered needle electrode enclosed in a conical quartz tube and grounded deionized water electrode. The discharges in the gas-phase, as well as in the two-phase, exhibit two discharge modes, i.e., the low current glow-like diffuse mode and the high current streamer-like constrict mode, with a mode transition, which exhibits a negative resistance of the discharges. The optical emission spectral analysis shows that the stronger diffusion of the water vapor into the discharge region in the two-phase discharges boosts up themore » generation of OH (A–X) radicals, and consequently, leads to a higher rotational temperature in the water-phase plasma plume than that of the gas-phase discharges. Both the increase of the power input and the decrease of the argon flow rate result in the increase of the rotational temperature in the plasma plume of the water-phase discharge. The stable two-phase discharges with a long plasma plume in the water-phase under a low power input and gas flow rate may show a promising prospect for the degradation of organic pollutants, e.g., printing and dyeing wastewater, in the field of environmental protection.« less

Enhanced degradation of p-chlorophenol in a novel pulsed high voltage discharge reactor.

PubMed

Bian, Wenjuan; Ying, Xiangli; Shi, Junwen

2009-03-15

The yields of active specie such as ozone, hydrogen peroxide and hydroxyl radical were all enhanced in a novel discharge reactor. In the reactor, the original formation rate of hydroxyl radical was 2.27 x 10(-7) mol L(-1)s(-1), which was about three times than that in the contrast reactor. Ozone was formed in gas-phase and was transferred into the liquid. The characteristic of mass transfer was better in the novel reactor than that in the contrast reactor, which caused much higher ozone concentration in liquid. The dissociation of hydrogen peroxide was more evident in the former, which promoted the formations of hydroxyl radical. The p-chlorophenol (4-CP) degradation was also enhanced. Most of the ozone transferred into the liquid and hydrogen peroxide generated by discharge could be utilized by the degradation process of 4-CP. About 97% 4-CP was removed in 36 min discharge in the novel reactor. Organic acids such as formic, acetic, oxalic, propanoic and maleic acid were generated and free chloride ions were released in the degradation process. With the formation of organic acid, the pH was decreased and the conductivity was increased.

A transport model for non-local heating of electrons in ICP reactors

NASA Astrophysics Data System (ADS)

Chang, C. H.; Bose, Deepak

1998-10-01

A new model has been developed for non-local heating of electrons in ICP reactors, based on a hydrodynamic approach. The model has been derived using the electron momentum conservation in azimuthal direction with electromagnetic and frictional forces respectively as driving force and damper of harmonic oscillatory motion of electrons. The resulting transport equations include the convection of azimuthal electron momentum in radial and axial directions, thereby accounting for the non-local effects. The azimuthal velocity of electrons and the resulting electrical current are coupled to the Maxwell's relations, thus forming a self-consistent model for non-local heating. This model is being implemented along with a set of Navier-Stokes equations for plasma dynamics and gas flow to simulate low-pressure (few mTorr's) ICP discharges. Characteristics of nitrogen plasma in a TCP 300mm etch reactor is being studied. The results will be compared against the available Langmuir probe measurements [Collison et al. JVST-A 16(1),1998].

Potential of electric discharge plasma methods in abatement of volatile organic compounds originating from the food industry.

PubMed

Preis, S; Klauson, D; Gregor, A

2013-01-15

Increased volatile organic compounds emissions and commensurate tightening of applicable legislation mean that the development and application of effective, cost-efficient abatement methods are areas of growing concern. This paper reviews the last two decades' publications on organic vapour emissions from food processing, their sources, impacts and treatment methods. An overview of the latest developments in conventional air treatment methods is presented, followed by the main focus of the paper, non-thermal plasma technology. The results of the review suggest that non-thermal plasma technology, in its pulsed corona discharge configuration, is an emerging treatment method with potential for low-cost, effective abatement of a wide spectrum of organic air pollutants. It is found that the combination of plasma treatment with catalysis is a development trend that demonstrates considerable potential. The as yet relatively small number of plasma treatment applications is considered to be due to the novelty of pulsed electric discharge techniques and a lack of reliable pulse generators and reactors. Other issues acting as barriers to widespread adoption of the technique include the possible formation of stable oxidation by-products, residual ozone and nitrogen oxides, and sensitivity towards air humidity. Copyright © 2012 Elsevier Ltd. All rights reserved.

Potential of Electric Power Production from Microbial Fuel Cell (MFC) in Evapotranspiration Reactor for Leachate Treatment Using Alocasia macrorrhiza Plant and Eleusine indica Grass

NASA Astrophysics Data System (ADS)

Zaman, Badrus; Wardhana, Irawan Wisnu

2018-02-01

Microbial fuel cell is one of attractive electric power generator from nature bacterial activity. While, Evapotranspiration is one of the waste water treatment system which developed to eliminate biological weakness that utilize the natural evaporation process and bacterial activity on plant roots and plant media. This study aims to determine the potential of electrical energy from leachate treatment using evapotranspiration reactor. The study was conducted using local plant, namely Alocasia macrorrhiza and local grass, namely Eleusine Indica. The system was using horizontal MFC by placing the cathodes and anodes at different chamber (i.e. in the leachate reactor and reactor with plant media). Carbon plates was used for chatode-anodes material with size of 40 cm x 10 cm x1 cm. Electrical power production was measure by a digital multimeter for 30 days reactor operation. The result shows electric power production was fluctuated during reactor operation from all reactors. The electric power generated from each reactor was fluctuated, but from the reactor using Alocasia macrorrhiza plant reach to 70 μwatt average. From the reactor using Eleusine Indica grass was reached 60 μwatt average. Electric power production fluctuation is related to the bacterial growth pattern in the soil media and on the plant roots which undergo the adaptation process until the middle of the operational period and then in stable growth condition until the end of the reactor operation. The results indicate that the evapotranspiration reactor using Alocasia macrorrhiza plant was 60-95% higher electric power potential than using Eleusine Indica grass in short-term (30-day) operation. Although, MFC system in evapotranspiration reactor system was one of potential system for renewable electric power generation.

Monitoring of tritium

DOEpatents

Corbett, James A.; Meacham, Sterling A.

1981-01-01

The fluid from a breeder nuclear reactor, which may be the sodium cooling fluid or the helium reactor-cover-gas, or the helium coolant of a gas-cooled reactor passes over the portion of the enclosure of a gaseous discharge device which is permeable to hydrogen and its isotopes. The tritium diffused into the discharge device is radioactive producing beta rays which ionize the gas (argon) in the discharge device. The tritium is monitored by measuring the ionization current produced when the sodium phase and the gas phase of the hydrogen isotopes within the enclosure are in equilibrium.

MRR and TWR evaluation on electrical discharge machining of Ti-6Al-4V using tungsten : copper composite electrode

NASA Astrophysics Data System (ADS)

Prasanna, J.; Rajamanickam, S.; Amith Kumar, O.; Karthick Raj, G.; Sathya Narayanan, P. V. V.

2017-05-01

In this paper Ti-6Al-4V used as workpiece material and it is keenly seen in variety of field including medical, chemical, marine, automotive, aerospace, aviation, electronic industries, nuclear reactor, consumer products etc., The conventional machining of Ti-6Al-4V is very difficult due to its distinctive properties. The Electrical Discharge Machining (EDM) is right choice of machining this material. The tungsten copper composite material is employed as tool material. The gap voltage, peak current, pulse on time and duty factor is considered as the machining parameter to analyze the machining characteristics Material Removal Rate (MRR) and Tool Wear Rate (TWR). The Taguchi method is provided to work for finding the significant parameter of EDM. It is found that for MRR significant parameters rated in the following order Gap Voltage, Pulse On-Time, Peak Current and Duty Factor. On the other hand for TWR significant parameters are listed in line of Gap Voltage, Duty Factor, Peak Current and Pulse On-Time.

Applications in Nuclear Energy Security

NASA Astrophysics Data System (ADS)

Sheffield, Richard

2009-05-01

A key roadblock to development of additional nuclear power capacity is a concern over management of nuclear waste. Nuclear waste is predominantly comprised of used fuel discharged from operating nuclear reactors. The roughly 100 operating US reactors currently produce about 20% of the US electricity and will create about 87,000 tons of such discharged or ``spent'' fuel over the course of their lifetimes. The long-term radioactivity of the spent fuel drives the need for deep geologic storage that remains stable for millions of years. Nearly all issues related to risks to future generations arising from long-term disposal of such spent nuclear fuel is attributable to approximately the 1% made up primarily of minor actinides. If we can reduce or eliminate this 1% of the spent fuel, then within a few hundred years the toxic nature of the spent fuel drops below that of the natural uranium ore that was originally mined for nuclear fuel. The minor actinides can be efficiently eliminated through nuclear transmutation using as a driver fast-neutrons produced by a spallation process initiated with a high-energy proton beam. This presentation will cover the system design considerations and issues of an accelerator driven transmutation system.

NEUTRONIC REACTOR

DOEpatents

Ohlinger, L.A.; Wigner, E.P.; Weinberg, A.M.; Young, G.J.

1958-09-01

This patent relates to neutronic reactors of the heterogeneous water cooled type, and in particular to a fuel element charging and discharging means therefor. In the embodiment illustrated the reactor contains horizontal, parallel coolant tubes in which the fuel elements are disposed. A loading cart containing a magnzine for holding a plurality of fuel elements operates along the face of the reactor at the inlet ends of the coolant tubes. The loading cart is equipped with a ram device for feeding fuel elements from the magazine through the inlot ends of the coolant tubes. Operating along the face adjacent the discharge ends of the tubes there is provided another cart means adapted to receive irradiated fuel elements as they are forced out of the discharge ends of the coolant tubes by the incoming new fuel elements. This cart is equipped with a tank coataining a coolant, such as water, into which the fuel elements fall, and a hydraulically operated plunger to hold the end of the fuel element being discharged. This inveation provides an apparatus whereby the fuel elements may be loaded into the reactor, irradiated therein, and unloaded from the reactor without stopping the fiow of the coolant and without danger to the operating personnel.

Effect of voltage waveform on dielectric barrier discharge ozone production efficiency

NASA Astrophysics Data System (ADS)

Mericam-Bourdet, N.; Kirkpatrick, M. J.; Tuvache, F.; Frochot, D.; Odic, E.

2012-03-01

Dielectric barrier discharges (DBDs) are commonly used for gas effluent cleanup and ozone generation. For these applications, the energy efficiency of the discharge is a major concern. This paper reports on investigations carried out on the voltage shape applied to DBD reactor electrodes, aiming to evaluate a possible energy efficiency improvement for ozone production. Two DBD reactor geometries were used: pin-to-pin and cylinder-to-cylinder, both driven either by a bi-directional power supply (voltage rise rate 1 kV/μs) or by a pulsed power supply (voltage rise rate 1 kV/ns). Ozone formed in dry air was measured at the reactor outlet. Special attention was paid to discharge input power evaluation using different methods including instantaneous current-voltage product and transferred charge-applied voltage figures. The charge transferred by the discharges was also correlated to the ozone production. It is shown that, in the case of the DBD reactors under investigation, the applied voltage shape has no influence on the ozone production efficiency. For the considered voltage rise rate, the charge deposit on the dielectric inserted inside the discharge gap is the important factor (as opposed to the voltage shape) governing the efficiency of the discharge - it does this by tailoring the duration of the current peak into the tens of nanosecond range.

Stimulation of the hydrolytic stage for biogas production from cattle manure in an electrochemical bioreactor.

PubMed

Samani, Saeed; Abdoli, Mohammad Ali; Karbassi, Abdolreza; Amin, Mohammad Mehdi

Electrical current in the hydrolytic phase of the biogas process might affect biogas yield. In this study, four 1,150 mL single membrane-less chamber electrochemical bioreactors, containing two parallel titanium plates were connected to the electrical source with voltages of 0, -0.5, -1 and -1.5 V, respectively. Reactor 1 with 0 V was considered as a control reactor. The trend of biogas production was precisely checked against pH, oxidation reduction potential and electrical power at a temperature of 37 ± 0.5°C amid cattle manure as substrate for 120 days. Biogas production increased by voltage applied to Reactors 2 and 3 when compared with the control reactor. In addition, the electricity in Reactors 2 and 3 caused more biogas production than Reactor 4. Acetogenic phase occurred more quickly in Reactor 3 than in the other reactors. The obtained results from Reactor 4 were indicative of acidogenic domination and its continuous behavior under electrical stimulation. The results of the present investigation clearly revealed that phasic electrical current could enhance the efficiency of biogas production.

AN EVALUATION OF HEAVY WATER REACTORS FOR POWER

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herron, D.P.; Newkirk, W.H.; Puishes, A.

1957-10-01

Reference designs for pressurized and direct-boiling D/sub 2/O reactors were prepared for electrical outputs of 20, 100, and 250 electrical Mw. A number of possible core designs were considered and those utilized which seemed most appropriate to give low-cost power. The technology and costs available today were employed in the preparation of the over-all plant designs. The Consolidated Western Steel Division of U. S. Steel Corporation assisted by preparing a comprehensive report on the design of large pressure vessels and containment vessels. Zr-clad U fuel elements were used as the study basis, but the effect of using UO/sub 2/ andmore » stainless steel cladding was also considered. The principal results found were: (1) Over a wide range of operating conditions snd economic situations, enriched U (up to perhaps 1.4% U/sup 235/) is presently more economic to employ in D/sub 2/O reactors than is natural U. (2) In the longer range, the use of natural U may become more economic as Zr fabrication costs decrease, continuous charge-discharge devices are developed to permit longer exposure levels, and pressure-vessel technology advances so that the large critical masses and core diameters required are not such sn economic penalty on the natural U. The results agree quite well with the data and discussions of the Canadians. (auth)« less

Evolution of Spatial pH Distribution in Aqueous Solution induced by Atmospheric Pressure Plasma

NASA Astrophysics Data System (ADS)

Takahashi, Shigenori; Mano, Kakeru; Hayashi, Yui; Takada, Noriharu; Kanda, Hideki; Goto, Motonobu

2016-09-01

Discharge plasma at gas-liquid interface produces some active species, and then they affect chemical reactions in aqueous solution, where pH of aqueous solution is changed due to redox species. The pH change of aqueous solution is an important factor for chemical reactions. However, spatial pH distribution in a reactor during the discharge has not been clarified yet. Thus, this work focused on spatial pH distribution of aqueous solution when pulsed discharge plasma was generated from a copper electrode in gas phase to aqueous solution in a reactor. Experiments were conducted using positive unipolar pulsed power. The unipolar pulsed voltage at +8.0 kV was applied to the copper electrode and the bottom of the reactor was grounded. The size of the reactor was 80 mm wide, 10 mm deep, and 40 mm high. The electrode was set at distance of 2 mm from the solution surface. Anthocyanins were contained in the aqueous solution as a pH indicator. The change pH solution spread horizontally, and low pH region of 10 mm in depth was formed. After discharge for 10 minutes, the low pH region was diffused toward the bottom of the reactor. After discharge for 60 minutes, the pH of the whole solution decreased.

A Numerical Study of the Non-Ideal Behavior, Parameters, and Novel Applications of an Electrothermal Plasma Source

NASA Astrophysics Data System (ADS)

Winfrey, A. Leigh

Electrothermal plasma sources have numerous applications including hypervelocity launchers, fusion reactor pellet injection, and space propulsion systems. The time evolution of important plasma parameters at the source exit is important in determining the suitability of the source for different applications. In this study a capillary discharge code has been modified to incorporate non-ideal behavior by using an exact analytical model for the Coulomb logarithm in the plasma electrical conductivity formula. Actual discharge currents from electrothermal plasma experiments were used and code results for both ideal and non-ideal plasma models were compared to experimental data, specifically the ablated mass from the capillary and the electrical conductivity as measured by the discharge current and the voltage. Electrothermal plasma sources operating in the ablation-controlled arc regime use discharge currents with pulse lengths between 100 micros to 1 ms. Faster or longer or extended flat-top pulses can also be generated to satisfy various applications of ET sources. Extension of the peak current for up to an additional 1000 micros was tested. Calculations for non-ideal and ideal plasma models show that extended flattop pulses produce more ablated mass, which scales linearly with increased pulse length while other parameters remain almost constant. A new configuration of the PIPE source has been proposed in order to investigate the formation of plasmas from mixed materials. The electrothermal segmented plasma source can be used for studies related to surface coatings, surface modification, ion implantation, materials synthesis, and the physics of complex mixed plasmas. This source is a capillary discharge where the ablation liner is made from segments of different materials instead of a single sleeve. This system should allow for the modeling and characterization of the growth plasma as it provides all materials needed for fabrication through the same method. An ablation-free capillary discharge computer code has been developed to model plasma flow and acceleration of pellets for fusion fueling in magnetic fusion reactors. Two case studies with and without ablation, including different source configurations have been studied here. Velocities necessary for fusion fueling have been achieved. New additions made to the code model incorporate radial heat and energy transfer and move ETFLOW towards being a 2-D model of the plasma flow. This semi 2-D approach gives a view of the behavior of the plasma inside the capillary as it is affected by important physical parameters such as radial thermal heat conduction and their effect on wall ablation.

Effect of various gases and chemical catalysts on phenol degradation pathways by pulsed electrical discharges.

PubMed

Shen, Yongjun; Lei, Lecheng; Zhang, Xingwang; Zhou, Minghua; Zhang, Yi

2008-02-11

The processes of phenol degradation by pulsed electrical discharges were investigated under several kinds of discharge atmospheres (oxygen, argon, nitrogen and ozone) and chemical catalysts (ferrous ion and hydrogen peroxide). The temporal variations of the concentrations of phenol and the intermediate products were monitored by HPLC and GC-MS, respectively. It has been found that the effect of various gases bubbling on phenol degradation rate ranked in the following order: oxygen-containing ozone>oxygen>argon>nitrogen. The high gas bubbling flow rate was beneficial to the removal of phenol. It was found that the degradation proceeded differently when in the presence and absence of catalysts. The phenol removal rate was increased when ferrous ion was added. This considerable enhancement may be due to the Fenton's reaction. What's more, putting the chemical additives hydrogen peroxide into the reactor led to a dramatic increase in phenol degradation rate. The mechanism was due to the direct or indirect photolysis and pyrolysis destruction in plasma channel. Furthermore, the intermediate products were monitored by GC-MS under three degradation conditions. More THBs were generated under degradation conditions without gases bubbling or adding any catalyst, and more DHBs under the condition of adding ferrous ion, and more carboxylic acids under the condition of oxygen-containing ozone gas bubbling. Consequently, three distinct degradation pathways based on different conditions were proposed.

The simplest equivalent circuit of a pulsed dielectric barrier discharge and the determination of the gas gap charge transfer

NASA Astrophysics Data System (ADS)

Pipa, A. V.; Koskulics, J.; Brandenburg, R.; Hoder, T.

2012-11-01

The concept of the simplest equivalent circuit for a dielectric barrier discharge (DBD) is critically reviewed. It is shown that the approach is consistent with experimental data measured either in large-scale sinusoidal-voltage driven or miniature pulse-voltage driven DBDs. An expression for the charge transferred through the gas gap q(t) is obtained with an accurate account for the displacement current and the values of DBD reactor capacitance. This enables (i) the significant reduction of experimental error in the determination of q(t) in pulsed DBDs, (ii) the verification of the classical electrical theory of ozonizers about maximal transferred charge qmax, and (iii) the development of a graphical method for the determination of qmax from charge-voltage characteristics (Q-V plots, often referred as Lissajous figures) measured under pulsed excitation. The method of graphical presentation of qmax is demonstrated with an example of a Q-V plot measured under pulsed excitation. The relations between the discharge current jR(t), the transferred charge q(t), and the measurable parameters are presented in new forms, which enable the qualitative interpretation of the measured current and voltage waveforms without the knowledge about the value of the dielectric barrier capacitance Cd. Whereas for quantitative evaluation of electrical measurements, the accurate estimation of the Cd is important.

Corona-assisted flame synthesis of ultrafine titania particles

NASA Astrophysics Data System (ADS)

Vemury, Srinivas; Pratsinis, Sotiris E.

1995-06-01

Synthesis of ultrafine titania particles is investigated in a diffusion flame aerosol reactor in the presence of a gaseous electric discharge (corona) created by two needle electrodes. The corona wind flattens the flame and reduces the particle residence time at high temperatures, resulting in smaller primary particle sizes and lower level of crystallinity. Increasing the applied potential from 5 to 8 kV reduces the particle size from 50 to 25 nm and the rutile content from 20 to 8 wt %. Coronas provide a clean and simple technique that facilitates gas phase synthesis of nanosized materials with controlled size and crystallinity.

Valorization of biogas into liquid hydrocarbons in plasma-catalyst reactor

NASA Astrophysics Data System (ADS)

Nikravech, Mehrdad; Rahmani, Abdelkader; Labidi, Sana; Saintini, Noiric

2016-09-01

Biogas represents an important source of renewable energy issued from biological degradation of biomass. It is planned to produce in Europe the amount of biogas equivalent to 6400 kWh electricity and 4500 kteo (kilo tons equivalent oil) in 2020. Currently the biogas is used in cogeneration engines to produce heat and electricity directly in farms or it is injected in gas networks after purification and odorisation. The aim of this work is to propose a third option that consists of valorization of biogas by transformation into liquid hydrocarbons like acetone, methanol, ethanol, acetic acid etc. These chemicals, among the most important feed materials for chemical industries, retain CO2 molecules participating to reduce the greenhouse gas emissions and have high storage energy capacity. We developed a low temperature atmospheric plasma-catalyst reactor (surface dielectric barrier discharge) to transform biogas into chemicals. The conversion rates of CH4 and CO2 are respectively about 50% and 30% depending on operational conditions. The energetic cost is 25 eV/molecule. The yields of liquid hydrocarbon reaches currently 10% wt. More the 11 liquid chemicals are observed in the liquid fraction. Acknowledgements are due to SPC Programme Energie de demain.

Efficient synthesis of ammonia from N2 and H2 alone in a ferroelectric packed-bed DBD reactor

NASA Astrophysics Data System (ADS)

Gómez-Ramírez, A.; Cotrino, J.; Lambert, R. M.; González-Elipe, A. R.

2015-12-01

A detailed study of ammonia synthesis from hydrogen and nitrogen in a planar dielectric barrier discharge (DBD) reactor was carried out. Electrical parameters were systematically varied, including applied voltage and frequency, electrode gap, and type of ferroelectric material (BaTiO3 versus PZT). For selected operating conditions, power consumption and plasma electron density were estimated from Lissajous diagrams and by application of the Bolsig  +  model, respectively. Optical emission spectroscopy was used to follow the evolution of plasma species (\\text{N}{{\\text{H}}*},{{\\text{N}}*},~{N}2+~\\text{and} ~{N}2* ) as a function of applied voltage with both types of ferroelectric material. PZT gave both greater energy efficiency and higher ammonia yield than BaTiO3: 0.9 g NH3 kWh-1 and 2.7% single pass N2 conversion, respectively. This performance is substantially superior to previously published findings on DBD synthesis of NH3 from N2 and H2 alone. The influence of electrical working parameters, the beneficial effect of PZT and the importance of controlling reactant residence time are rationalized in a reaction model that takes account of the principal process variables

The G value in plasma and radiation chemistry

NASA Technical Reports Server (NTRS)

Baird, James K.; Miller, George P.; Li, Ning

1990-01-01

The application of the G-value concept to plasma chemistry is considered. A general formula which expresses the G value for a general reaction in terms of experimentally controllable parameters is derived by applying simple gas-dynamic theory to a plasma reactor with straight walls. The formula expresses the G value as a function of the electrical power absorbed, the fraction of molecules transformed, and the flow rate of the gas entering the reactor. The formula was applied to the ammonia plasma radio-frequency discharge data of d'Agostino et al. (1981); the results showed that the G(-NH3) value lies in the range of 6.0-20 molecules/100 eV, depending on the conditions. This similarity of the G(-NH3) value with Peterson's (1974) range 2.7-10 found for the gas-phase radiolysis of ammonia, suggests that there might be a common reaction mechanism initiated by inelastic electron-molecule collisions.

Control of reactor coolant flow path during reactor decay heat removal

DOEpatents

Hunsbedt, Anstein N.

1988-01-01

An improved reactor vessel auxiliary cooling system for a sodium cooled nuclear reactor is disclosed. The sodium cooled nuclear reactor is of the type having a reactor vessel liner separating the reactor hot pool on the upstream side of an intermediate heat exchanger and the reactor cold pool on the downstream side of the intermediate heat exchanger. The improvement includes a flow path across the reactor vessel liner flow gap which dissipates core heat across the reactor vessel and containment vessel responsive to a casualty including the loss of normal heat removal paths and associated shutdown of the main coolant liquid sodium pumps. In normal operation, the reactor vessel cold pool is inlet to the suction side of coolant liquid sodium pumps, these pumps being of the electromagnetic variety. The pumps discharge through the core into the reactor hot pool and then through an intermediate heat exchanger where the heat generated in the reactor core is discharged. Upon outlet from the heat exchanger, the sodium is returned to the reactor cold pool. The improvement includes placing a jet pump across the reactor vessel liner flow gap, pumping a small flow of liquid sodium from the lower pressure cold pool into the hot pool. The jet pump has a small high pressure driving stream diverted from the high pressure side of the reactor pumps. During normal operation, the jet pumps supplement the normal reactor pressure differential from the lower pressure cold pool to the hot pool. Upon the occurrence of a casualty involving loss of coolant pump pressure, and immediate cooling circuit is established by the back flow of sodium through the jet pumps from the reactor vessel hot pool to the reactor vessel cold pool. The cooling circuit includes flow into the reactor vessel liner flow gap immediate the reactor vessel wall and containment vessel where optimum and immediate discharge of residual reactor heat occurs.

Distribution of radionuclides in Dardanelle Reservoir sediments.

PubMed

Forgy, J R; Epperson, C E; Swindle, D L

1984-02-01

Natural and reactor-discharged gamma-ray emitting radionuclides were measured in Dardanelle Reservoir surface sediments taken near the Arkansas Nuclear One Power Plant site. Samples represented several water depths and particle sizes, at 33 locations, in a field survey conducted in early September 1980. Radionuclide contents of dry sediments ranged as follows: natural radioactivity (40K as well as uranium and thorium decay products) 661-1210 Bq/kg; and reactor discharged radioactivity (137Cs, 134Cs, 60Co,, 58Co, 54Mn), no detectable activity to 237 Bq/kg. In general, radionuclide contents were positively correlated with decreasing sediment particle size. The average external whole-body and skin doses from all measurable reactor-discharged radionuclides were calculated according to the mathematical formula for determining external dose from sediment given by the U.S. Nuclear Regulatory Commission (NRC). Inside the discharge embayment near the reactor discharge canal, the doses were 1.7 X 10(-3) mSv/yr to the whole body and 2.0 X 10(-3) mSv/yr to the skin. Outside this area, the doses were 0.15 X 10(-3) and 0.18 X 10(-3) mSv/yr to the whole body and skin, respectively.

METHOD AND APPARATUS FOR HANDLING RADIOACTIVE PRODUCTS

DOEpatents

Nicoll, D.

1959-02-24

A device is described for handling fuel elements being discharged from a nuclear reactor. The device is adapted to be disposed beneath a reactor within the storage canal for spent fuel elements. The device is comprised essentially of a cylinder pivotally mounted to a base for rotational motion between a vertical position. where the mouth of the cylinder is in the top portion of the container for receiving a fuel element discharged from a reactor into the cylinder, and a horizontal position where the mouth of the cylinder is remote from the top portion of the container and the fuel element is discharged from the cylinder into the storage canal. The device is operated by hydraulic pressure means and is provided with a means to prevent contaminated primary liquid coolant in the reactor system from entering the storage canal with the spent fuel element.

Langmuir probe study of a magnetically enhanced RF plasma source at pressures below 0.1 Pa

NASA Astrophysics Data System (ADS)

Kousal, Jaroslav; Tichý, Milan; Šebek, Ondřej; Čechvala, Juraj; Biederman, Hynek

2011-08-01

The majority of plasma polymerization sources operate at pressures higher than 1 Pa. At these pressures most common deposition methods do not show significant directionality. One way of enhancing the directional effects is to decrease the working pressure to increase the mean free path of the reactive molecules. The plasma source used in this work was designed to study the plasma polymerization process at pressures below 0.1 Pa. The source consists of the classical radio frequency (RF) (13.56 MHz, capacitive coupled) tubular reactor enhanced by an external magnetic circuit. The working gas is introduced into the discharge by a capillary. This forms a relatively localized zone of higher pressure where the monomer is activated. Due to the magnetic field, the plasma is constricted near the axis of the reactor with nearly collisionless gas flow. The plasma parameters were obtained using a double Langmuir probe. Plasma density in the range ni = 1013-1016 m-3 was obtained in various parts of the discharge under typical conditions. The presence of the magnetic field led to the presence of relatively strong electric fields (103 V m-1) and relatively high electron energies up to several tens of eV in the plasma.

2D simulation of active species and ozone production in a multi-tip DC air corona discharge

NASA Astrophysics Data System (ADS)

Meziane, M.; Eichwald, O.; Sarrette, J. P.; Ducasse, O.; Yousfi, M.

2011-11-01

The present paper shows for the first time in the literature a complete 2D simulation of the ozone production in a DC positive multi-tip to plane corona discharge reactor crossed by a dry air flow at atmospheric pressure. The simulation is undertaken until 1 ms and involves tens of successive discharge and post-discharge phases. The air flow is stressed by several monofilament corona discharges generated by a maximum of four anodic tips distributed along the reactor. The nonstationary hydrodynamics model for reactive gas mixture is solved using the commercial FLUENT software. During each discharge phase, thermal and vibrational energies as well as densities of radical and metastable excited species are locally injected as source terms in the gas medium surrounding each tip. The chosen chemical model involves 10 neutral species reacting following 24 reactions. The obtained results allow us to follow the cartography of the temperature and the ozone production inside the corona reactor as a function of the number of high voltage anodic tips.

Positive direct current corona discharges in single wire-duct electrostatic precipitators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yehia, Ashraf, E-mail: yehia30161@yahoo.com; Department of Physics, Faculty of Science, Assiut University, Assiut 71516, Arab Republic of Egypt; Abdel-Fattah, E.

This paper is aimed to study the characteristics of the positive dc corona discharges in single wire-duct electrostatic precipitators. Therefore, the corona discharges were formed inside dry air fed single wire-duct reactor under positive dc voltage at the normal atmospheric conditions. The corona current-voltage characteristics curves have been measured in parallel with the ozone concentration generated inside the reactor under different discharge conditions. The corona current-voltage characteristics curves have agreed with a semi empirical equation derived from the previous studies. The experimental results of the ozone concentration generated inside the reactor were formulated in the form of an empirical equationmore » included the different parameters that were studied experimentally. The obtained equations are valid to expect both the current-voltage characteristics curves and the corresponding ozone concentration that generates with the positive dc corona discharges inside single wire-duct electrostatic precipitators under any operating conditions in the same range of the present study.« less

Novel electrode structure in a DBD reactor applied to the degradation of phenol in aqueous solution

NASA Astrophysics Data System (ADS)

Mercado-Cabrera, Antonio; Peña-Eguiluz, Rosendo; López-Callejas, Régulo; Jaramillo-Sierra, Bethsabet; Valencia-Alvarado, Raúl; Rodríguez-Méndez, Benjamín; Muñoz-Castro, Arturo E.

2017-07-01

Phenol degradation experimental results are presented in a similar wastewater aqueous solution using a non-thermal plasma reactor in a coaxial dielectric barrier discharge. The novelty of the work is that one of the electrodes of the reactor has the shape of a hollow screw which shows an enhanced efficiency compared with a traditional smooth structure. The experimentation was carried out with gas mixtures of 90% Ar-10% O2, 80% Ar-20% O2 and 0% Ar-100% O2. After one hour of treatment the removal efficiency was 76%, 92%, and 97%, respectively, assessed with a gas chromatographic mass spectrometry technique. For both reactors used, the ozone concentration was measured. The screw electrode required less energy, for all gas mixtures, than the smooth electrode, to maintain the same ozone concentration. On the other hand, it was also observed that in both electrodes the electrical conductivity of the solution changed slightly from ˜0.0115 S m-1 up to ˜0.0430 S m-1 after one hour of treatment. The advantages of using the hollow screw electrode structure compared with the smooth electrode were: (1) lower typical power consumption, (2) the generation of a uniform plasma throughout the reactor benefiting the phenol degradation, (3) a relatively lower temperature of the aqueous solution during the process, and (4) the plasma generation length is larger.

Passive filtration of air egressing from nuclear containment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malloy, III, John D

2017-09-26

A nuclear reactor includes a reactor core comprising fissile material disposed in a reactor pressure vessel. A radiological containment contains the nuclear reactor. A containment compartment contains the radiological containment. A heat sink includes a chimney configured to develop an upward-flowing draft in response to heated fluid flowing into a lower portion of the chimney. A fluid conduit is arranged to receive fluid from the containment compartment and to discharge into the chimney. A filter may be provided, with the fluid conduit including a first fluid conduit arranged to receive fluid from the containment compartment and to discharge into anmore » inlet of the filter, and a second fluid conduit arranged to receive fluid from an outlet of the filter and to discharge into the chimney. As the draft is developed passively, there is no need for a blower or pump configured to move fluid through the fluid conduit.« less

Plasma Discharge with Different Electrode Diameters for Reducing Methylene Blue Concentration

NASA Astrophysics Data System (ADS)

Rasyidah, H.; Kusumandari; Saraswati, T. E.; Anwar, M.

2018-03-01

Recently, plasma technology has gained attention since it overcomes the shortcomings of water treatment. This research studies the effect of electrode diameter of plasma discharge reactors on the concentration reduction of methylene blue as an organic solution. The plasma discharge reactor was built from a pair of stainless needle electrodes connected with high-AC voltage. The electrodes were placed approximately 2 mm above the solution and stirred at 5.5 rpm. The diameters of the electrodes were 2, 3.2 and 4 mm. The times for plasma treatment were set at 2, 4, 6, 8 and 10 min. Absorbance, temperature and pH of the solution were measured to know the effects of electrode diameter of the plasma reactor. Absorbance and pH significantly decreased after plasma treatment. The best of the absorbance reduction were obtained when the sample was treated under plasma discharge using the smallest diameter electrodes for 8-10 min.

Effect of water on sulfur dioxide (SO2) and nitrogen oxides (NOx) removal from flue gas in a direct current corona discharge reactor

NASA Astrophysics Data System (ADS)

Yang, Jiaxiang; Chi, Xiaochun; Dong, Limin

2007-05-01

A direct current (dc) corona discharge reactor composed of needle-plate electrodes in a glass container filled with flue gas was designed. To clarify the influence of water on discharge characteristics, water was introduced in the plasma reactor as electrode where plate electrode is immersed, under the application of dc voltage. Experiment results show that (1) corona wind forming between high-voltage needle electrode and water by corona discharge enhances the cleaning efficiency of flue gas due to the existence of water and the cleaning efficiency will increase with the increase of applied dc voltage within definite range and (2) both removal efficiencies of NOx and SO2 increased in the presence of water, which reach up to 98% for SO2, and about 85% for NOx under suitable conditions. These results play an important role in flue gas cleanup research.

Reactor core isolation cooling system

DOEpatents

Cooke, F.E.

1992-12-08

A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom. 1 figure.

Reactor core isolation cooling system

DOEpatents

Cooke, Franklin E.

1992-01-01

A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom.

Catalytic Reactor For Oxidizing Mercury Vapor

DOEpatents

Helfritch, Dennis J.

1998-07-28

A catalytic reactor (10) for oxidizing elemental mercury contained in flue gas is provided. The catalyst reactor (10) comprises within a flue gas conduit a perforated corona discharge plate (30a, b) having a plurality of through openings (33) and a plurality of projecting corona discharge electrodes (31); a perforated electrode plate (40a, b, c) having a plurality of through openings (43) axially aligned with the through openings (33) of the perforated corona discharge plate (30a, b) displaced from and opposing the tips of the corona discharge electrodes (31); and a catalyst member (60a, b, c, d) overlaying that face of the perforated electrode plate (40a, b, c) opposing the tips of the corona discharge electrodes (31). A uniformly distributed corona discharge plasma (1000) is intermittently generated between the plurality of corona discharge electrode tips (31) and the catalyst member (60a, b, c, d) when a stream of flue gas is passed through the conduit. During those periods when corona discharge (1000) is not being generated, the catalyst molecules of the catalyst member (60a, b, c, d) adsorb mercury vapor contained in the passing flue gas. During those periods when corona discharge (1000) is being generated, ions and active radicals contained in the generated corona discharge plasma (1000) desorb the mercury from the catalyst molecules of the catalyst member (60a, b, c, d), oxidizing the mercury in virtually simultaneous manner. The desorption process regenerates and activates the catalyst member molecules.

Dielectric Barrier Discharges: Pulsed Breakdown, Electrical Characterization and Chemistry

DTIC Science & Technology

2013-06-01

DIELECTRIC BARRIER DISCHARGES : PULSED BREAKDOWN, ELECTRICAL CHARACTERIZATION AND CHEMISTRY  R. Brandenburg, H. Höft, T. Hoder, A. Pipa, R...for pulsed driven Dielectric Barrier Discharges (DBDs) in particular. Fast electrical, optical and spectroscopic methods enable the study of...2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Dielectric Barrier Discharges : Pulsed Breakdown, Electrical Characterization

Porous stabilized beds, methods of manufacture thereof and articles comprising the same

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klausner, James F.; Mei, Renwei; Momen, Ayyoub Mehdizadeh

Disclosed herein is a method comprising disposing a first particle in a reactor; the first particle being a magnetic particle or a particle that can be influenced by a magnetic field, an electric field or a combination of an electrical field and a magnetic field; fluidizing the first particle in the reactor; applying a uniform magnetic field, a uniform electrical field or a combination of a uniform magnetic field and a uniform electrical field to the reactor; elevating the temperature of the reactor; and fusing the first particles to form a monolithic solid.

Removal properties of diesel exhaust particles by a dielectric barrier discharge reactor.

PubMed

Suzuki, Ken-ichiro; Takeuchi, Naomi; Madokoro, Kazuhiko; Fushimi, Chihiro; Yao, Shuiliang; Fujioka, Yuichi; Nihei, Yoshimasa

2008-02-01

The removal properties of diesel exhaust particles (DEP) were investigated using an engine exhaust particle size spectrometer (EEPS), field emission-type scanning electron microscopy (FE-SEM) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). DEP were treated using a dielectric barrier discharge (DBD) reactor installed in the tail pipe of a diesel engine, and a model DBD reactor fed with DEP in the mixture of N(2) and O(2). When changing the experimental parameters of both the plasma conditions and the engine load conditions, we obtained characteristic information of DEP treated with plasma discharges from the particle diameter and the composition. In evaluating the model DBD reactor, it became clear that there were two types of plasma processes (reactions with active oxygen species to yield CO(2) and reactions with active nitrogen species to yield nitrogen containing compounds). Moreover, from the result of a TOF-SIMS analysis, the characteristic secondary ions, such as C(2)H(6)N(+), C(4)H(12)N(+), and C(10)H(20)N(2)(+), were strongly detected from the DEP surfaces during the plasma discharges. This indicates that the nitrogen contained hydrocarbons were generated by plasma reactions.

The application of a non-thermal plasma generated by gas-liquid gliding arc discharge in sterilization

NASA Astrophysics Data System (ADS)

Du, Chang Ming; Wang, Jing; Zhang, Lu; Xia Li, Hong; Liu, Hui; Xiong, Ya

2012-01-01

Gliding arc discharge has been investigated in recent years as an innovative physicochemical technique for contaminated water treatment at atmospheric pressure and ambient temperature. In this study we tested a gas-liquid gliding arc discharge reactor, the bacterial suspension of which was treated circularly. When the bacterial suspension was passed through the electrodes and circulated at defined flow rates, almost 100% of the bacteria were killed in less than 3.0 min. Experimental results showed that it is possible to achieve an abatement of 7.0 decimal logarithm units within only 30 s. Circulation flow rates and types of feeding gas caused a certain impact on bacteria inactivation, but the influences are not obvious. So, under the promise of sterilization effect, industrial applications can select their appropriate operating conditions. All inactivation curves presented the same three-phase profile showing an apparent sterilization effect. Analysis of the scanning electron microscope images of bacterial cells supports the speculation that the gas-liquid gliding arc discharge plasma is acting under various mechanisms driven essentially by oxidation and the effect of electric field. These results enhance the possibility of applying gas-liquid gliding arc discharge decontamination systems to disinfect bacterial-contaminated water. Furthermore, correlational research indicates the potential applications of this technology in rapid sterilization of medical devices, spacecraft and food.

156. ARAIII Reactor building (ARA608) Electrical and control details of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

156. ARA-III Reactor building (ARA-608) Electrical and control details of mobile work bridge over reactor and pipiing pits. Aerojet-general 880-area/GCRE-608-E-6. Date: November 1958. Ineel index code no. 063-0608-10-013-102621. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

Application of Molten Salt Reactor Technology to Nuclear Electric Propulsion Mission

NASA Technical Reports Server (NTRS)

Patton, Bruce; Sorensen, Kirk; Rodgers, Stephen L. (Technical Monitor)

2002-01-01

Nuclear electric propulsion (NEP) and planetary surface power missions require reactors that are lightweight, operationally robust, and scalable in power for widely varying scientific mission objectives. Molten salt reactor technology meets all of these requirements and offers an interesting alternative to traditional gas cooled, liquid metal, and heat pipe space reactors.

Synthesis of superior fast charging-discharging nano-LiFePO4/C from nano-FePO4 generated using a confined area impinging jet reactor approach.

PubMed

Liu, Xiao-min; Yan, Pen; Xie, Yin-Yin; Yang, Hui; Shen, Xiao-dong; Ma, Zi-Feng

2013-06-14

LiFePO4/C nanocomposites with excellent electrochemical performance is synthesized from nano-FePO4, generated by a novel method using a confined area impinging jet reactor (CIJR). When discharged at 80 C (13.6 Ag(-1)), the LiFePO4/C delivers a discharge capacity of 95 mA h g(-1), an energy density of 227 W h kg(-1) and a power density of 34 kW kg(-1).

Guiding of Long-Distance Electric Discharges by Combined Femtosecond and Nanosecond Pulses Emitted by Hybrid KrF Laser System

DTIC Science & Technology

2014-01-30

AFRL-AFOSR-UK-TR-2014-0040 Guiding of long-distance electric discharges by combined femtosecond and nanosecond pulses emitted by...To) 27 September 2010 – 31 December 2013 4. TITLE AND SUBTITLE Guiding of long-distance electric discharges by combined femtosecond and...plasma channels in the atmosphere and laser guiding of high-voltage electric discharges . 15. SUBJECT TERMS EOARD, triggering

Investigation of flame structure in plasma-assisted turbulent premixed methane-air flame

NASA Astrophysics Data System (ADS)

Hualei, ZHANG; Liming, HE; Jinlu, YU; Wentao, QI; Gaocheng, CHEN

2018-02-01

The mechanism of plasma-assisted combustion at increasing discharge voltage is investigated in detail at two distinctive system schemes (pretreatment of reactants and direct in situ discharge). OH-planar laser-induced fluorescence (PLIF) technique is used to diagnose the turbulent structure methane-air flame, and the experimental apparatus consists of dump burner, plasma-generating system, gas supply system and OH-PLIF system. Results have shown that the effect of pretreatment of reactants on flame can be categorized into three regimes: regime I for voltage lower than 6.6 kV; regime II for voltage between 6.6 and 11.1 kV; and regime III for voltage between 11.1 and 12.5 kV. In regime I, aerodynamic effect and slower oxidation of higher hydrocarbons generated around the inner electrode tip plays a dominate role, while in regime III, the temperature rising effect will probably superimpose on the chemical effect and amplify it. For wire-cylinder dielectric barrier discharge reactor with spatially uneven electric field, the amount of radicals and hydrocarbons are decreased monotonically in radial direction which affects the flame shape. With regard to in situ plasma discharge in flames, the discharge pattern changes from streamer type to glow type. Compared with the case of reactants pretreatment, the flame propagates further in the upstream direction. In the discharge region, the OH intensity is highest for in situ plasma assisted combustion, indicating that the plasma energy is coupled into flame reaction zone.

Spent Nuclear Fuel Disposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, John C.

One interdisciplinary field devoted to achieving the end-state of used nuclear fuel (UNF) through reuse and/or permanent disposal. The reuse option aims to make use of the remaining energy content in UNF and reduce the amount of long-lived radioactive materials that require permanent disposal. The planned approach in the U.S., as well as in many other countries worldwide, is direct permanent disposal in a deep geologic repository. Used nuclear fuel is fuel that has been irradiated in a nuclear reactor to the point where it is no longer capable of sustaining operational objectives. The vast majority (by mass) of UNFmore » is from electricity generation in commercial nuclear power reactors. Furthermore, the other main source of UNF in the U.S. is the Department of Energy’s (DOE) and other federal agencies’ operation of reactors in support of federal government missions, such as materials production, nuclear propulsion, research, testing, and training. Upon discharge from a reactor, UNF emits considerable heat from radioactive decay. Some period of active on-site cooling (e.g., 2 or more years) is typically required to facilitate efficient packaging and transportation to a disposition facility. Hence, the field of UNF disposition broadly includes storage, transportation and ultimate disposition. See also: Nuclear Fission (content/nuclear-fission/458400), Nuclear Fuels (/content/nuclear-fuels/458600), Nuclear Fuel Cycle (/content/nuclear-fuel-cycle/458500), Nuclear Fuels Reprocessing (/content/nuclear-fuels-reprocessing/458700), Nuclear Power (/content/nuclear-power/459600), Nuclear Reactor (/content/nuclear-reactor/460100), Radiation (/content/radiation/566300), and Radioactive Waste Management (/content/radioactive-waste-management/568900).« less

Spent Nuclear Fuel Disposition

DOE PAGES

Wagner, John C.

2016-05-22

One interdisciplinary field devoted to achieving the end-state of used nuclear fuel (UNF) through reuse and/or permanent disposal. The reuse option aims to make use of the remaining energy content in UNF and reduce the amount of long-lived radioactive materials that require permanent disposal. The planned approach in the U.S., as well as in many other countries worldwide, is direct permanent disposal in a deep geologic repository. Used nuclear fuel is fuel that has been irradiated in a nuclear reactor to the point where it is no longer capable of sustaining operational objectives. The vast majority (by mass) of UNFmore » is from electricity generation in commercial nuclear power reactors. Furthermore, the other main source of UNF in the U.S. is the Department of Energy’s (DOE) and other federal agencies’ operation of reactors in support of federal government missions, such as materials production, nuclear propulsion, research, testing, and training. Upon discharge from a reactor, UNF emits considerable heat from radioactive decay. Some period of active on-site cooling (e.g., 2 or more years) is typically required to facilitate efficient packaging and transportation to a disposition facility. Hence, the field of UNF disposition broadly includes storage, transportation and ultimate disposition. See also: Nuclear Fission (content/nuclear-fission/458400), Nuclear Fuels (/content/nuclear-fuels/458600), Nuclear Fuel Cycle (/content/nuclear-fuel-cycle/458500), Nuclear Fuels Reprocessing (/content/nuclear-fuels-reprocessing/458700), Nuclear Power (/content/nuclear-power/459600), Nuclear Reactor (/content/nuclear-reactor/460100), Radiation (/content/radiation/566300), and Radioactive Waste Management (/content/radioactive-waste-management/568900).« less

Low Pressure Experimental Simulation of Electrical Discharges Above and Inside a Cloud

NASA Technical Reports Server (NTRS)

Jarzembski, Maurice A.; Srivastava, Vandana

1996-01-01

A low pressure laboratory experiment to generate sporadic electrical discharges in either a particulate dielectric or air, representing a competing path of preferred electrical breakdown, was investigated. At high pressures, discharges occurred inside the dielectric particulate; at low pressures, discharges occurred outside the dielectric particulate; at a transition pressure regime, which depends on conductivity of the dielectric particulate, discharges were simultaneously generated in both particulate dielectric and air. Unique use of a particulate dielectric was critical for sporadic discharges at lower pressures which were not identical in character to discharges without the particulate dielectric. Application of these experimental results to the field of atmospheric electricity and simulation of the above-cloud type discharges that have recently been documented, called jets and sprites, are discussed.

Modeling Chilled-Water Storage System Components for Coupling to a Small Modular Reactor in a Nuclear Hybrid Energy System

NASA Astrophysics Data System (ADS)

Misenheimer, Corey Thomas

The intermittency of wind and solar power puts strain on electric grids, often forcing carbonbased and nuclear sources of energy to operate in a load-follow mode. Operating nuclear reactors in a load-follow fashion is undesirable due to the associated thermal and mechanical stresses placed on the fuel and other reactor components. Various Thermal Energy Storage (TES) elements and ancillary energy applications can be coupled to nuclear (or renewable) power sources to help absorb grid instabilities caused by daily electric demand changes and renewable intermittency, thereby forming the basis of a candidate Nuclear Hybrid Energy System (NHES). During the warmer months of the year in many parts of the country, facility air-conditioning loads are significant contributors to the increase in the daily peak electric demand. Previous research demonstrated that a stratified chilled-water storage tank can displace peak cooling loads to off-peak hours. Based on these findings, the objective of this work is to evaluate the prospect of using a stratified chilled-water storage tank as a potential TES reservoir for a nuclear reactor in a NHES. This is accomplished by developing time-dependent models of chilled-water system components, including absorption chillers, cooling towers, a storage tank, and facility cooling loads appropriate for a large office space or college campus, as a callable FORTRAN subroutine. The resulting TES model is coupled to a high-fidelity mPower-sized Small Modular Reactor (SMR) Simulator, with the goal of utilizing excess reactor capacity to operate several sizable chillers in order to keep reactor power constant. Chilled-water production via single effect, lithium bromide (LiBr) absorption chillers is primarily examined in this study, although the use of electric chillers is briefly explored. Absorption chillers use hot water or low-pressure steam to drive an absorption-refrigeration cycle. The mathematical framework for a high-fidelity dynamic absorption chiller model is presented. The transient FORTRAN model is grounded on time-dependent mass, species, and energy conservation equations. Due to the vast computational costs of the high-fidelity model, a low-fidelity absorption chiller model is formulated and calibrated to mimic the behavior of the high-fidelity model. Stratified chilled-water storage tank performance is characterized using Computational Fluid Dynamics (CFD). The geometry employed in the CFD model represents a 5-million-gallon storage tank currently in use at a North Carolina college campus. Simulation results reveal the laminar numerical model most closely aligns with actual tank charging and discharging data. A subsequent parametric study corroborates storage tank behavior documented throughout literature and industry. Two absorption chiller configurations are considered. The first involves bypassing lowpressure steam from the low-pressure turbine to absorption chillers during periods of excess reactor capacity in order to keep reactor power constant. Simulation results show steam conditions downstream of the turbine control valves are a strong function of turbine load, and absorption chiller performance is hindered by reduced turbine impulse pressures at reduced turbine demands. A more suitable configuration entails integrating the absorption chillers into a flash vessel system that is thermally coupled to a sensible heat storage system. The sensible heat storage system is able to maintain reactor thermal output constant at 100% and match turbine output with several different electric demand profiles. High-pressure condensate in the sensible heat storage system is dropped across a let-down orifice and flashed in an ideal separator. Generated steam is sent to a bank of absorption chillers. Simulation results show enough steam is available during periods of reduced turbine demand to power four large absorption chillers to charge a 5-million-gallon stratified chilled-water storage tank, which is used to offset cooling loads in an adjacent facility. The coupled TES systems operating in conjunction with an SMR comprise the foundation of a tightly coupled NHES.

Uniform and non-uniform modes of nanosecond-pulsed dielectric barrier discharge in atmospheric air: fast imaging and spectroscopic measurements of electric field

PubMed Central

Liu, Chong; Dobrynin, Danil; Fridman, Alexander

2014-01-01

In this study, we report experimental results on fast ICCD imaging of development of nanosecond-pulsed dielectric barrier discharge (DBD) in atmospheric air and spectroscopic measurements of electric field in the discharge. Uniformity of the discharge images obtained with nanosecond exposure times were analyzed using chi-square test. The results indicate that DBD uniformity strongly depends on applied (global) electric field in the discharge gap, and is a threshold phenomenon. We show that in the case of strong overvoltage on the discharge gap (provided by fast rise times), there is transition from filamentary to uniform DBD mode which correlates to the corresponding decrease of maximum local electric field in the discharge. PMID:25071294

Uniform and non-uniform modes of nanosecond-pulsed dielectric barrier discharge in atmospheric air: fast imaging and spectroscopic measurements of electric field.

PubMed

Liu, Chong; Dobrynin, Danil; Fridman, Alexander

2014-06-25

In this study, we report experimental results on fast ICCD imaging of development of nanosecond-pulsed dielectric barrier discharge (DBD) in atmospheric air and spectroscopic measurements of electric field in the discharge. Uniformity of the discharge images obtained with nanosecond exposure times were analyzed using chi-square test. The results indicate that DBD uniformity strongly depends on applied (global) electric field in the discharge gap, and is a threshold phenomenon. We show that in the case of strong overvoltage on the discharge gap (provided by fast rise times), there is transition from filamentary to uniform DBD mode which correlates to the corresponding decrease of maximum local electric field in the discharge.

A Review of Control Strategy of the Large-scale of Electric Vehicles Charging and Discharging Behavior

NASA Astrophysics Data System (ADS)

Kong, Lingyu; Han, Jiming; Xiong, Wenting; Wang, Hao; Shen, Yaqi; Li, Ying

2017-05-01

Large scale access of electric vehicles will bring huge challenges to the safe operation of the power grid, and it’s important to control the charging and discharging of the electric vehicle. First of all, from the electric quality and network loss, this paper points out the influence on the grid caused by electric vehicle charging behaviour. Besides, control strategy of electric vehicle charging and discharging has carried on the induction and the summary from the direct and indirect control. Direct control strategy means control the electric charging behaviour by controlling its electric vehicle charging and discharging power while the indirect control strategy by means of controlling the price of charging and discharging. Finally, for the convenience of the reader, this paper also proposed a complete idea of the research methods about how to study the control strategy, taking the adaptability and possibility of failure of electric vehicle control strategy into consideration. Finally, suggestions on the key areas for future research are put up.

Method and apparatus for chemically altering fluids in continuous flow

DOEpatents

Heath, W.O.; Virden, J.W. Jr.; Richardson, R.L.; Bergsman, T.M.

1993-10-19

The present invention relates to a continuous flow fluid reactor for chemically altering fluids. The reactor operates on standard frequency (50 to 60 Hz) electricity. The fluid reactor contains particles that are energized by the electricity to form a corona throughout the volume of the reactor and subsequently a non-equilibrium plasma that interacts with the fluid. Particles may form a fixed bed or a fluid bed. Electricity may be provided through electrodes or through an inductive coil. Fluids include gases containing exhaust products and organic fuels requiring oxidation. 4 figures.

Method and apparatus for chemically altering fluids in continuous flow

DOEpatents

Heath, William O.; Virden, Jr., Judson W.; Richardson, R. L.; Bergsman, Theresa M.

1993-01-01

The present invention relates to a continuous flow fluid reactor for chemically altering fluids. The reactor operates on standard frequency (50 to 60 Hz) electricity. The fluid reactor contains particles that are energized by the electricity to form a corona throughout the volume of the reactor and subsequently a non-equilibrium plasma that interacts with the fluid. Particles may form a fixed bed or a fluid bed. Electricity may be provided through electrodes or through an inductive coil. Fluids include gases containing exhaust products and organic fuels requiring oxidation.

Miniature whirlwinds produced in the laboratory by high-voltage electrical discharges.

PubMed

Ryan, R T; Vonnegut, B

1970-06-12

Laboratory experiments showed that under certain conditions of vorticity the electrical heatinig produced by a high-voltage discharge at atmospheric pressure can cause the formation of a miniature tornado-like vortex. Once it forms, this vortex stabilizes the electrical discharge along its axis and changes its character from that of a spark to high-pressure variety of a glow discharge. Electrical and dynamic parameters were measured. By relating observations and measurements made in these experiments to previous work and to analogous situations in nature, it is concluded that the heating produced by electrical discharges in a large storm may play a significant role in forming and maintaining natural tornadoes.

Small modular reactors are 'crucial technology'

NASA Astrophysics Data System (ADS)

Johnston, Hamish

2018-03-01

Small modular nuclear reactors (SMRs) offer a way for the UK to reduce carbon dioxide emissions from electricity generation, while allowing the country to meet the expected increase in demand for electricity from electric vehicles and other uses.

An experimental system for symmetric capacitive rf discharge studies

NASA Astrophysics Data System (ADS)

Godyak, V. A.; Piejak, R. B.; Alexandrovich, B. M.

1990-09-01

An experimental system has been designed and built to comprehensively study the electrical and plasma characteristics in symmetric capacitively coupled rf discharges at low gas pressures. Descriptions of the system concept, the discharge chamber, the vacuum-gas control system, and the rf matching and electrical measurement system are presented together with some results of electrical measurements carried out in an argon discharge at 13.56 MHz. The system has been specifically designed to facilitate external discharge parameter measurements and probe measurements and to be compatible with a wide variety of other diagnostics. External electrical measurements and probe measurements within the discharge show that it is an ideal vehicle to study low-pressure rf discharge physics. Measurements from this system should be comparable to one-dimensional rf symmetric capacitive discharge theories and may help to verify them. Although only a few results are given here, the system has been operated reliably over a wide range of gas pressures and should give reproducible and accurate results for discharge electrical characteristics and plasma parameters over a wide range of driving frequency and gas components.

X-ray Sensitive Material

DTIC Science & Technology

2015-12-01

The research resulted in a composite material that holds a quasi-permanent electric charge and rapidly discharges the electric charge upon X-ray...quasi-permanent electric charge and rapidly discharge the electric charge upon X-ray exposure. The composite material combined the properties of an...9 7. Schematic of Circuit for Recording Sample’s Capacitor Discharge ............... 12 8. Schematic of Circuit for

Zero discharge performance of an industrial pilot-scale plant treating palm oil mill effluent.

PubMed

Wang, Jin; Mahmood, Qaisar; Qiu, Jiang-Ping; Li, Yin-Sheng; Chang, Yoon-Seong; Chi, Li-Na; Li, Xu-Dong

2015-01-01

Palm oil is one of the most important agroindustries in Malaysia. Huge quantities of palm oil mill effluent (POME) pose a great threat to aqueous environment due to its very high COD. To make full use of discharged wastes, the integrated "zero discharge" pilot-scale industrial plant comprising "pretreatment-anaerobic and aerobic process-membrane separation" was continuously operated for 1 year. After pretreatment in the oil separator tank, 55.6% of waste oil in raw POME could be recovered and sold and anaerobically digested through 2 AnaEG reactors followed by a dissolved air flotation (DAF); average COD reduced to about 3587 mg/L, and biogas production was 27.65 times POME injection which was used to generate electricity. The aerobic effluent was settled for 3 h or/and treated in MBR which could remove BOD3 (30°C) to less than 20 mg/L as required by Department of Environment of Malaysia. After filtration by UF and RO membrane, all organic compounds and most of the salts were removed; RO permeate could be reused as the boiler feed water. RO concentrate combined with anaerobic surplus sludge could be used as biofertilizer.

Performance characteristics of an electric vehicle lead-acid battery pack at elevated temperatures

NASA Technical Reports Server (NTRS)

Chapman, P.

1982-01-01

Discharge testing data electric car battery pack over initial electrolyte temperature variations between 27 and 55 C are presented. The tests were conducted under laboratory conditions and then compared to detailed electric vehicle simulation models. Battery discharge capacity increased with temperature for constant current discharges, and battery energy capacity increased with temperature for constant power discharges. Dynamometer tests of the electric test vehicle showed an increase in range of 25% for the higher electrolyte temperature.

[Selection of a SHF-plasma device for carbon dioxide and hydrogen recycling in a physical-chemical life support system].

PubMed

Klimarev, S I

2003-01-01

A waveguide SHF plasmotron was chosen for carbon dioxide and hydrogen recycling in a low-temperature plasma in the Bosch reactor. To increase electric intensity within the discharge capacitor, thickness of the waveguide thin wall was changed for 10 mm. A method for calculating the compensated exponential smooth transition to align two similar lines (waveguides) with sections of 72 x 34 mm and 72 x 10 mm to transfer SHF energies from the generator to plasma was proposed. Calculation of the smooth transition has been used in final refinement of the HSF plasmotron design as a component of a physical-chemical LSS.

Time-resolved processes in a pulsed electrical discharge in argon bubbles in water

NASA Astrophysics Data System (ADS)

Gershman, S.; Belkind, A.

2010-12-01

A phenomenological picture of a pulsed electrical discharge in gas bubbles in water is produced by combining electrical, spectroscopic, and imaging characterization methods. The discharge is generated by applying 1 μ s pulses of 5 to 20 kV between a needle and a disk electrode submerged in water. An Ar gas bubble surrounds the tip of the needle electrode. Imaging, electrical characteristics, and time-resolved optical emission spectroscopic data suggest a fast streamer propagation mechanism and the formation of a plasma channel in the bubble. Comparing the electrical and imaging data for consecutive pulses applied to the bubble at a frequency of 1 Hz indicates that each discharge proceeds as an entirely new process with no memory of the previous discharge aside from the presence of long-lived chemical species, such as ozone and oxygen. Imaging and electrical data show the presence of two discharge events during each applied voltage pulse, a forward discharge near the beginning of the applied pulse depositing charge on the surface of the bubble and a reverse discharge removing the accumulated charge from the water/gas interface when the applied voltage is turned off. The pd value of ~ 300-500 torr cm, the 1 μs long pulse duration, low repetition rate, and unidirectional character of the applied voltage pulses make the discharge process here unique compared to the traditional corona or dielectric barrier discharges.

A study of the glow discharge plasma jet of the novel Hamburger-electrode

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Wenzheng, E-mail: wzhliu@bjtu.edu.cn; Ma, Chuanlong, E-mail: 15121452@bjtu.edu.cn; Yang, Xiao

2016-08-15

To generate atmospheric pressure glow discharge plasma jets (APGDPJs), a novel Hamburger-electrode was proposed. Through the study on electric field distributions, flow field distributions, and characteristics of the discharge and jet, we found that adopting the mode of dielectric barrier discharge with non-uniform thickness of dielectric, it was easy to form the strong electric field areas which were conducive to generate discharge and electric field distributions with large electric field intensity in the narrow gap and weak electric field intensity in the wide gap that were not inclined to form a filament discharge. Using the structure of evenly distributed innermore » electrodes, it was easy to weaken the pressure of strong electric field areas and form flow field distributions which is beneficial for taking out the high density charged particles and generating APGDPJs. Stable APGDPJs in nitrogen with 3.5 mm in diameter and 9 mm in length were formed by using the novel Hamburger-electrode.« less

Advanced Demonstration and Test Reactor Options Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petti, David Andrew; Hill, R.; Gehin, J.

Global efforts to address climate change will require large-scale decarbonization of energy production in the United States and elsewhere. Nuclear power already provides 20% of electricity production in the United States (U.S.) and is increasing in countries undergoing rapid growth around the world. Because reliable, grid-stabilizing, low emission electricity generation, energy security, and energy resource diversity will be increasingly valued, nuclear power’s share of electricity production has a potential to grow. In addition, there are non electricity applications (e.g., process heat, desalination, hydrogen production) that could be better served by advanced nuclear systems. Thus, the timely development, demonstration, and commercializationmore » of advanced nuclear reactors could diversify the nuclear technologies available and offer attractive technology options to expand the impact of nuclear energy for electricity generation and non-electricity missions. The purpose of this planning study is to provide transparent and defensible technology options for a test and/or demonstration reactor(s) to be built to support public policy, innovation and long term commercialization within the context of the Department of Energy’s (DOE’s) broader commitment to pursuing an “all of the above” clean energy strategy and associated time lines. This planning study includes identification of the key features and timing needed for advanced test or demonstration reactors to support research, development, and technology demonstration leading to the commercialization of power plants built upon these advanced reactor platforms. This planning study is consistent with the Congressional language contained within the fiscal year 2015 appropriation that directed the DOE to conduct a planning study to evaluate “advanced reactor technology options, capabilities, and requirements within the context of national needs and public policy to support innovation in nuclear energy”. Advanced reactors are defined in this study as reactors that use coolants other than water. Advanced reactor technologies have the potential to expand the energy applications, enhance the competitiveness, and improve the sustainability of nuclear energy.« less

Nozzle for electric dispersion reactor

DOEpatents

Sisson, Warren G.; Basaran, Osman A.; Harris, Michael T.

1998-01-01

A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

Nozzle for electric dispersion reactor

DOEpatents

Sisson, Warren G.; Basaran, Osman A.; Harris, Michael T.

1995-01-01

A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

An investigation of the treatment of particulate matter from gasoline engine exhaust using non-thermal plasma.

PubMed

Ye, Dan; Gao, Dengshan; Yu, Gang; Shen, Xianglin; Gu, Fan

2005-12-09

A plasma reactor with catalysts was used to treat exhaust gas from a gasoline engine in order to decrease particulate matter (PM) emissions. The effect of non-thermal plasma (NTP) of the dielectric discharges on the removal of PM from the exhaust gas was investigated experimentally. The removal efficiency of PM was based on the concentration difference in PM for particle diameters ranging from 0.3 to 5.0 microm as measured by a particle counter. Several factors affecting PM conversion, including the density of plasma energy, reaction temperature, flow rate of exhaust gas, were investigated in the experiment. The results indicate that PM removal efficiency ranged approximately from 25 to 57% and increased with increasing energy input in the reactor, reaction temperature and residence time of the exhaust gas in the reactor. Enhanced removal of the PM was achieved by filling the discharge gap of the reactor with Cu-ZSM-5 catalyst pellets. In addition, the removal of unburned hydrocarbons was studied. Finally, available approaches for PM conversion were analyzed involving the interactions between discharge and catalytic reactions.

Review of the methods to form hydrogen peroxide in electrical discharge plasma with liquid water

NASA Astrophysics Data System (ADS)

Locke, Bruce R.; Shih, Kai-Yuan

2011-06-01

This paper presents a review of the literature dealing with the formation of hydrogen peroxide from plasma processes. Energy yields for hydrogen peroxide generation by plasma from water span approximately three orders of magnitude from 4 × 10-2 to 80 g kWh-1. A wide range of plasma processes from rf to pulsed, ac, and dc discharges directly in the liquid phase have similar energy yields and may thus be limited by radical quenching processes at the plasma-liquid interface. Reactor modification using discharges in bubbles and discharges over the liquid phase can provide modest improvements in energy yield over direct discharge in the liquid, but the interpretation is complicated by additional chemical reactions of gas phase components such as ozone and nitrogen oxides. The highest efficiency plasma process utilizes liquid water droplets that may enhance efficiency by sequestering hydrogen peroxide in the liquid and by suppressing decomposition reactions by radicals from the gas and at the interface. Kinetic simulations of water vapor reported in the literature suggest that plasma generation of hydrogen peroxide should approach 45% of the thermodynamics limit, and this fact coupled with experimental studies demonstrating improvements with the presence of the condensed liquid phase suggest that further improvements in energy yield may be possible. Plasma generation of hydrogen peroxide directly from water compares favorably with a number of other methods including electron beam, ultrasound, electrochemical and photochemical methods, and other chemical processes.

Electrical discharges in the atmosphere of Venus

NASA Technical Reports Server (NTRS)

Ksanfomaliti, L. V.; Vasilchikov, N. M.; Ganpantserova, O. F.; Petrova, Y. V.; Suvorov, A. P.; Filippov, G. F.; Yablonskaya, O. V.; Yabrova, L. V.

1979-01-01

Data received from Venera 11 and 12 experiments involving the electrical activity of the atmosphere of Venus show that the electrical discharges occur in the cloud layer. Their energy is roughly the same as in terrestrial lightning, but with a pulse repetition frequency of the discharges which is much greater.

Nozzle for electric dispersion reactor

DOEpatents

Sisson, Warren G.; Harris, Michael T.; Scott, Timothy C.; Basaran, Osman A.

1998-01-01

A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

Nozzle for electric dispersion reactor

DOEpatents

Sisson, Warren G.; Harris, Michael T.; Scott, Timothy C.; Basaran, Osman A.

1996-01-01

A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

Nozzle for electric dispersion reactor

DOEpatents

Sisson, W.G.; Basaran, O.A.; Harris, M.T.

1998-04-14

A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 4 figs.

Nozzle for electric dispersion reactor

DOEpatents

Sisson, W.G.; Basaran, O.A.; Harris, M.T.

1995-11-07

A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 4 figs.

Nuclear electric propulsion reactor control systems status

NASA Technical Reports Server (NTRS)

Ferg, D. A.

1973-01-01

The thermionic reactor control system design studies conducted over the past several years for a nuclear electric propulsion system are described and summarized. The relevant reactor control system studies are discussed in qualitative terms, pointing out the significant advantages and disadvantages including the impact that the various control systems would have on the nuclear electric propulsion system design. A recommendation for the reference control system is made, and a program for future work leading to an engineering model is described.

Morphological Processing of Ultraviolet Emissions of Electrical Corona Discharge for Analysis and Diagnostic Use

NASA Technical Reports Server (NTRS)

Schubert, Matthew R.; Moore, Andrew J.

2015-01-01

Electron cascades from electrical discharge produce secondary emissions from atmospheric plasma in the ultraviolet band. For a single point of discharge, these emissions exhibit a stereotypical discharge morphology, with latent information about the discharge location. Morphological processing can uncover the location and therefore can have diagnostic utility.

Morphological processing of ultraviolet emissions of electrical corona discharge for analysis and diagnostic use.

PubMed

Schubert, Matthew; Moore, Andrew J

2016-03-01

Electron cascades from electrical discharge produce secondary emissions from atmospheric plasma in the ultraviolet band. For a single point of discharge, these emissions exhibit a stereotypical discharge morphology, with latent information about the discharge location. Morphological processing can uncover the location and therefore have diagnostic utility.

How to increase the efficiency of the electrical discharge method for destruction of nonconductive solid materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voitenko, N. V., E-mail: tevn@hvd.tpu.ru; Yudin, A. S.; Kuznetsova, N. S.

The paper deals with the relevance of using electrical discharge technology for construction works in the city. The technical capabilities of the installation for the multi-borehole electro-discharge splitting off and destruction of rocks and concrete are described. The ways to increase the efficiency of the electrical discharge method for the destruction of solids are proposed. In order to augment the discharge circuit energy, the energy storage is separated into two individual capacitor batteries. The throttle with the inductance of 28.6 μH is installed in one of the batteries, which increases the duration of the channel energy release to 400 μsmore » and the efficiency of electrical discharge splitting off of concrete.« less

15. ELECTRICAL REACTOR SHELVES, CONSTRUCTED OF CONCRETE IN THE BASEMENT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. ELECTRICAL REACTOR SHELVES, CONSTRUCTED OF CONCRETE IN THE BASEMENT ALONG EAST WALL, WITH REACTOR PADS BEHIND FRAMED AND SCREENED CAGE, AND PORCELAIN-LINED CABLE DUCTS VISIBLE IN WALL NEAR FLOOR AT REAR - Bonneville Power Administration South Bank Substation, I-84, South of Bonneville Dam Powerhouse, Bonneville, Multnomah County, OR

Nozzle for electric dispersion reactor

DOEpatents

Sisson, W.G.; Harris, M.T.; Scott, T.C.; Basaran, O.A.

1996-04-02

A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 5 figs.

Nozzle for electric dispersion reactor

DOEpatents

Sisson, W.G.; Harris, M.T.; Scott, T.C.; Basaran, O.A.

1998-06-02

A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 5 figs.

Transfer of a cold atmospheric pressure plasma jet through a long flexible plastic tube

NASA Astrophysics Data System (ADS)

Kostov, Konstantin G.; Machida, Munemasa; Prysiazhnyi, Vadym; Honda, Roberto Y.

2015-04-01

This work proposes an experimental configuration for the generation of a cold atmospheric pressure plasma jet at the downstream end of a long flexible plastic tube. The device consists of a cylindrical dielectric chamber where an insulated metal rod that serves as high-voltage electrode is inserted. The chamber is connected to a long (up to 4 m) commercial flexible plastic tube, equipped with a thin floating Cu wire. The wire penetrates a few mm inside the discharge chamber, passes freely (with no special support) along the plastic tube and terminates a few millimeters before the tube end. The system is flushed with Ar and the dielectric barrier discharge (DBD) is ignited inside the dielectric chamber by a low frequency ac power supply. The gas flow is guided by the plastic tube while the metal wire, when in contact with the plasma inside the DBD reactor, acquires plasma potential. There is no discharge inside the plastic tube, however an Ar plasma jet can be extracted from the downstream tube end. The jet obtained by this method is cold enough to be put in direct contact with human skin without an electric shock. Therefore, by using this approach an Ar plasma jet can be generated at the tip of a long plastic tube far from the high-voltage discharge region, which provides the safe operation conditions and device flexibility required for medical treatment.

Dynamic characteristics of electric discharge in liquid under ultrasonic cavitation

NASA Astrophysics Data System (ADS)

Bulychev, N. A.; Kazaryan, M. A.; Averyushkin, A. S.; Kirichenko, M. N.; Zakharyan, Robert; Chernov, A. A.

2018-04-01

The characteristics of electrical discharges in liquid media under the influence of intense ultrasonic vibrations are investigated and the difference in dynamic characteristics of discharges before cavitation and after cavitation begins. The experiments carried out during this work made it possible to establish that in a liquid in an intense ultrasonic field above the cavitation threshold there exists a special form of an electric discharge characterized by volumetric luminescence in the entire space between the electrodes and the current-voltage characteristic inherent in an anomalous glow discharge in a gas.

Dicarboxylic acids from electric discharge

NASA Technical Reports Server (NTRS)

Zeitman, B.; Chang, S.; Lawless, J. G.

1974-01-01

An investigation was conducted concerning the possible synthesis of a suite of dicarboxylic acids similar to that found in the Murchison meteorite. The investigation included the conduction of a chemical evolution experiment which simulated electric discharge through the primitive atmosphere of the earth. The suite of dicarboxylic acids obtained in the electric discharge experiment is similar to that of the Murchison meteorite, except for the fact that 2-chlorosuccinic acid is present in the spark discharge.

Experimental study and simulation of space charge stimulated discharge

NASA Astrophysics Data System (ADS)

Noskov, M. D.; Malinovski, A. S.; Cooke, C. M.; Wright, K. A.; Schwab, A. J.

2002-11-01

The electrical discharge of volume distributed space charge in poly(methylmethacrylate) (PMMA) has been investigated both experimentally and by computer simulation. The experimental space charge was implanted in dielectric samples by exposure to a monoenergetic electron beam of 3 MeV. Electrical breakdown through the implanted space charge region within the sample was initiated by a local electric field enhancement applied to the sample surface. A stochastic-deterministic dynamic model for electrical discharge was developed and used in a computer simulation of these breakdowns. The model employs stochastic rules to describe the physical growth of the discharge channels, and deterministic laws to describe the electric field, the charge, and energy dynamics within the discharge channels and the dielectric. Simulated spatial-temporal and current characteristics of the expanding discharge structure during physical growth are quantitatively compared with the experimental data to confirm the discharge model. It was found that a single fixed set of physically based dielectric parameter values was adequate to simulate the complete family of experimental space charge discharges in PMMA. It is proposed that such a set of parameters also provides a useful means to quantify the breakdown properties of other dielectrics.

Influences of Excess Oscillation of Voltage Pulse and Discharge Mode on NO Removal Using Barrier-Type Plasma Reactor

NASA Astrophysics Data System (ADS)

Kadowaki, Kazunori; Suzuki, Yoshiaki; Ihori, Haruo; Kitani, Isamu

This paper presents experimental results of NO removal from a simulated exhausted-gas using a barrier type reactor with screw electrodes subjected to polarity-reversed voltage pulses. The polarity-reversed pulse was produced by direct grounding of a charged coaxial cable because a traveling wave voltage was negatively reflected at the grounding end with a change in its polarity and then it propagated to the plasma reactor at the opposite end. Influence of cable length on NO removal was studied for two kinds of cable connection, single-connected cable and parallel-connected cables. NO removal ratio for a 50m-long cable was lower than that for much shorter cables in both single and parallel connections when the applied voltage became high. Energy efficiency for NO removal also increased with decreasing the cable length. This was because excess discharges during the voltage oscillation caused by the large stored energy in the long cable resulted in reproduction of NO molecules. Energy efficiency was further improved by changing the discharge mode from dielectric barrier discharge (DBD) to surface discharge (SD). Energy efficiency was up to 110g/kWh with 55% NO removal ratio and 34g/kWh with 100% NO removal ratio by using a single 10m-long cable in SD mode.

A plug flow reactor model of a vanadium redox flow battery considering the conductive current collectors

NASA Astrophysics Data System (ADS)

König, S.; Suriyah, M. R.; Leibfried, T.

2017-08-01

A lumped-parameter model for vanadium redox flow batteries, which use metallic current collectors, is extended into a one-dimensional model using the plug flow reactor principle. Thus, the commonly used simplification of a perfectly mixed cell is no longer required. The resistances of the cell components are derived in the in-plane and through-plane directions. The copper current collector is the only component with a significant in-plane conductance, which allows for a simplified electrical network. The division of a full-scale flow cell into 10 layers in the direction of fluid flow represents a reasonable compromise between computational effort and accuracy. Due to the variations in the state of charge and thus the open circuit voltage of the electrolyte, the currents in the individual layers vary considerably. Hence, there are situations, in which the first layer, directly at the electrolyte input, carries a multiple of the last layer's current. The conventional model overestimates the cell performance. In the worst-case scenario, the more accurate 20-layer model yields a discharge capacity 9.4% smaller than that computed with the conventional model. The conductive current collector effectively eliminates the high over-potentials in the last layers of the plug flow reactor models that have been reported previously.

Investigation of plasma-sheath resonances in low pressure discharges

NASA Astrophysics Data System (ADS)

Naggary, Schabnam; Kemaneci, Efe; Brinkmann, Ralf Peter; Megahed, Mustafa

2016-09-01

Plasma sheath resonances (PSR) arise from a periodic exchange between the kinetic electron energy in the plasma bulk and the electric field energy in the sheath and can easily be excited by the sheath-generated harmonics of the applied RF. In this contribution, we employ a series of models to obtain a well-defined description of these phenomena. In the first part, we use a global model to study the influence of the nonlinear charge-voltage characteristics on the electron dynamics. However, the global model is restricted to the assumption of spatially constant potential at each driven and grounded electrode and thus delivers only the fundamental mode of the current. In order to remedy the deficiency, we introduce a spatially resolved model for arbitrary reactor geometries with no assumptions on the homogeneity of the plasma. An exact evaluation of the analytical solution is realized on the assumption of a cylinderical plasma reactor geometry with uniform conductance. Furthermore, the spatially resolved model is capable of being utilized for a more realistic CCP reactor geometry and non homogeneous plasma provided the conductance distribution is known. For this purpose, we use the CFD-ACE+ tool. The results show that the proposed multi-mode model provides a significant improvement. The authors gratefully acknowledge the financial support by the ESI Group and the SFB- TR 87.

Laser-assisted guiding of electric discharges around objects

PubMed Central

Clerici, Matteo; Hu, Yi; Lassonde, Philippe; Milián, Carles; Couairon, Arnaud; Christodoulides, Demetrios N.; Chen, Zhigang; Razzari, Luca; Vidal, François; Légaré, François; Faccio, Daniele; Morandotti, Roberto

2015-01-01

Electric breakdown in air occurs for electric fields exceeding 34 kV/cm and results in a large current surge that propagates along unpredictable trajectories. Guiding such currents across specific paths in a controllable manner could allow protection against lightning strikes and high-voltage capacitor discharges. Such capabilities can be used for delivering charge to specific targets, for electronic jamming, or for applications associated with electric welding and machining. We show that judiciously shaped laser radiation can be effectively used to manipulate the discharge along a complex path and to produce electric discharges that unfold along a predefined trajectory. Remarkably, such laser-induced arcing can even circumvent an object that completely occludes the line of sight. PMID:26601188

THERMOCHEMICAL HEAT STORAGE FOR CONCENTRATED SOLAR POWER

DOE Office of Scientific and Technical Information (OSTI.GOV)

PROJECT STAFF

2011-10-31

Thermal energy storage (TES) is an integral part of a concentrated solar power (CSP) system. It enables plant operators to generate electricity beyond on sun hours and supply power to the grid to meet peak demand. Current CSP sensible heat storage systems employ molten salts as both the heat transfer fluid and the heat storage media. These systems have an upper operating temperature limit of around 400 C. Future TES systems are expected to operate at temperatures between 600 C to 1000 C for higher thermal efficiencies which should result in lower electricity cost. To meet future operating temperature andmore » electricity cost requirements, a TES concept utilizing thermochemical cycles (TCs) based on multivalent solid oxides was proposed. The system employs a pair of reduction and oxidation (REDOX) reactions to store and release heat. In the storage step, hot air from the solar receiver is used to reduce the oxidation state of an oxide cation, e.g. Fe3+ to Fe2+. Heat energy is thus stored as chemical bonds and the oxide is charged. To discharge the stored energy, the reduced oxide is re-oxidized in air and heat is released. Air is used as both the heat transfer fluid and reactant and no storage of fluid is needed. This project investigated the engineering and economic feasibility of this proposed TES concept. The DOE storage cost and LCOE targets are $15/kWh and $0.09/kWh respectively. Sixteen pure oxide cycles were identified through thermodynamic calculations and literature information. Data showed the kinetics of re-oxidation of the various oxides to be a key barrier to implementing the proposed concept. A down selection was carried out based on operating temperature, materials costs and preliminary laboratory measurements. Cobalt oxide, manganese oxide and barium oxide were selected for developmental studies to improve their REDOX reaction kinetics. A novel approach utilizing mixed oxides to improve the REDOX kinetics of the selected oxides was proposed. It partially replaces some of the primary oxide cations with selected secondary cations. This causes a lattice charge imbalance and increases the anion vacancy density. Such vacancies enhance the ionic mass transport and lead to faster re-oxidation. Reoxidation fractions of Mn3O4 to Mn2O3 and CoO to Co3O4 were improved by up to 16 fold through the addition of a secondary oxide. However, no improvement was obtained in barium based mixed oxides. In addition to enhancing the short term re-oxidation kinetics, it was found that the use of mixed oxides also help to stabilize or even improve the TES properties after long term thermal cycling. Part of this improvement could be attributed to a reduced grain size in the mixed oxides. Based on the measurement results, manganese-iron, cobalt-aluminum and cobalt iron mixed oxides have been proposed for future engineering scale demonstration. Using the cobalt and manganese mixed oxides, we were able to demonstrate charge and discharge of the TES media in both a bench top fixed bed and a rotary kiln-moving bed reactor. Operations of the fixed bed configuration are straight forward but require a large mass flow rate and higher fluid temperature for charging. The rotary kiln makes direct solar irradiation possible and provides significantly better heat transfer, but designs to transport the TES oxide in and out of the reactor will need to be defined. The final reactor and system design will have to be based on the economics of the CSP plant. A materials compatibility study was also conducted and it identified Inconel 625 as a suitable high temperature engineering material to construct a reactor holding either cobalt or manganese mixed oxides. To assess the economics of such a CSP plant, a packed bed reactor model was established as a baseline. Measured cobalt-aluminum oxide reaction kinetics were applied to the model and the influences of bed properties and process parameters on the overall system design were investigated. The optimal TES system design was found to be a network of eight fixed bed reactors at 18.75 MWth each with charge and discharge temperatures between 1200 C and 600 C, which provides a constant output temperature of 900 C. The charge and discharge time are 8 hours each respectively. This design was integrated into a process flowsheet of a CSP plant and the system's economics were determined using AspenPlus and NREL's Solar Advisory Model. Storage cost is very sensitive to materials cost and was calculated to be based around $40/kWh for cobalt based mixed oxide. It can potentially decrease to $10/kWh based on reduced materials cost on a bulk scale. The corresponding calculated LCOE was between $0.22 and 0.30/kW-h. The high LCOE is a result of the high charging temperature required in this first design and the cost of cobalt oxide. It is expected that a moving bed reactor using manganese oxide will significantly improve the economics of the proposed concept.« less

Purification of inkjet ink from water using liquid phase, electric discharge polymerization and cellulosic membrane filtration.

PubMed

Jordan, Alexander T; Hsieh, Jeffery S; Lee, Daniel T

2013-01-01

A method to separate inkjet ink from water was developed using a liquid phase, electric discharge process. The liquid phase, electric discharge process with filtration or sedimentation was shown to remove 97% of inkjet ink from solutions containing between 0.1-0.8 g/L and was consistent over a range of treatment conditions. Additionally, particle size analysis of treated allyl alcohol and treated propanol confirmed the electric discharge treatment has a polymerization mechanism, and small molecule analysis of treated methanol using gas chromatography and mass spectroscopy confirmed the mechanism was free radical initiated polymerization.

Gravito-electrodynamics, Ehd and Their Applications To Natural Hazards and Laboratory Devices

NASA Astrophysics Data System (ADS)

Kikuchi, H.

For the past two decades, theory of dusty and dirty plasmas in space and in the labo - ratory has been developed on the basis of both unconventional gravito-electrody- nam ics and a new EHD (electrohydrodynamics) with novel concepts of electric re- connection and critical ionization velocity as well as modern concepts of self-organ- ization and chaos and has been applied to explanations of a variety of new dust-re- lated and meteorologyico-electric phenomena such as planetary (Saturn's and Jupi- ter's) dust layer or ring formation, terrestrial dust layer formation, terrestrial light - ning including winter thunderstorms, rocket and tower triggered lightning, planetary (Saturn's, Jupiter's, and Io's) lightning, nebular lightning, ball lightning, tornadic thunderstorms, whirlwinds, cloud-to-ionosphere discharges, pre-earthquake atmo- sphereic and ionospheric effects, and new laboratory devices such as electric undu - lators, a universal electric-cusp type plasma reactor for basic laboratory studies, sim- ulations of atmospheric phenomena and pollution control and gas cleaning, plasma processing and new material production for industrial applications, and new devices such as towards cancer treatment for biological and medical applications. Reference H. Kikuchi, Electrohydrodynamics in Dusty and Dirty plasmas, Kluwer Academic Publishers, Dordrecht/The Netherlands, 2001. For describing any plasmas, particle dynamics plays always fundamental and impor - tant roles in understanding all of plasma behaviors. A variety of descriptions in a magnetic field such as a guiding center approach have well been developed as a test-particle approach particularly for a base of MHD. This is still true for EHD or EMHD, but additional factors become significant due to the existence of space charges and electric fields for EHD or EMHD in dielectric or semiconducting fluids. In cosmic plasmas, the existence of double layers, electric and magnetic dipoles or quadru-poles often affects the particle motions drastically even if particles are uncharged, and can play a crucial role in planetary dust layer or ring formation. This is a new discov-ery and has been discussed in detail for the past several EGS meetings. In the presenc e of quadrupole-like charged cloud configurations which constitute electric cusps and mirrors, a neutral or uncharged particle can be accelerated in an electric cusp, reaching a maximum speed near a cusp boundary, if the environment is a tenuous gas whatever it may be neutral or ionized, and also can be reflected back at a mirror point. Otherwise, a dust in an electric cusp is capable for a source origin of plasma layer formation, gas discharges or lightnings due to additional effect of `criti-cal velocity' if the local electric fields around the dust produced by quadrupole-like charged clouds are sufficiently high beyond a gas-breakdown threshold. Then electric reconnection through the dust is followed by streamer or leader formation due to the critical ionization effect and consequent gas discharges or lightnings. One of major features of new electrodynamics, gravito-electrodynamics, and EHD is a new addition of two basic concepts of electric reconnection and critical ionization . First, one may recall that a distribution of scattered charged clouds is so ubiquitous in space and in the laboratory, even in our daily life, whatever they are of large-scale or small-scale, like thunderclouds in the atmosphere, charged clouds in interstellar space, charges on the belt of Van de Graff generator, and a system of miniature thunder-clouds produced by frictional electricity almost everywhere, typically on human hairs. All those cases are capable for electric reconnection. Whenever electric reconnection occurs through dusts in the atmosphere, it can be accompanied by a critical ioniza-tion flow . In this way, electric reconnection and critical ionization could be a signifi-cant cause of electrification and electric discharge and play important roles in a varie-ty of phenomena in meteorologico-electric, dusty and dirty plasma environments.

Electrical discharge heating of chondrules in the solar nebula

NASA Technical Reports Server (NTRS)

Love, Stanley G.; Keil, Klaus; Scott, Edward R. D.

1995-01-01

We present a rudimentary theoretical assessment of electrical discharge heating as a candidate mechanism for the formation of chondrules in the solar nebula. The discharge model combines estimates of the properties of the nebula, a mechanism for terrestrial thunderstorm electrification, and some fundamental electrical properties of gases. Large uncertainties in the model inputs limit these calculations to order-or-magnitude accuracy. Despite the uncertainty, it is possible to estimate an upper limit to the efficiency of nebular discharges at melting millimeter-sized stony objects. We find that electrical arcs analogous to terrestrial lightning could have occurred in the nebula, but that under most conditions these discharges probably could not have melted chondrules. Despite our difficulties, we believe the topic worthy of further investigation and suggest some experiments which could improve our understanding of nebular discharges.

[Determination of electric field distribution in dielectric barrier surface glow discharge by spectroscopic method].

PubMed

Li, Xue-chen; Jia, Peng-ying; Liu, Zhi-hui; Li, Li-chun; Dong, Li-fang

2008-12-01

In the present paper, stable glow discharges were obtained in air at low pressure with a dielectric barrier surface discharge device. Light emission from the discharge was detected by photomultiplier tubes and the research results show that the light signal exhibited one discharge pulse per half cycle of the applied voltage. The light pulses were asymmetric between the positive half cycle and the negative one of the applied voltage. The images of the glow surface discharge were processed by Photoshop software and the results indicate that the emission intensity remained almost constant for different places with the same distance from the powered electrode, while the emission intensity decreased with the distance from the powered electrode increasing. In dielectric barrier discharge, net electric field is determined by the applied voltage and the wall charges accumulated on the dielectric layer during the discharge, and consequently, it is important to obtain information about the net electric field distribution. For this purpose, optical emission spectroscopy method was used. The distribution of the net electric field can be deduced from the intensity ratio of spectral line 391.4 nm emitted from the first negative system of N2+ (B 2sigma u+ -->X 2sigma g+) to 337.1 nm emitted from the second positive system of N2 (C 3IIu-B 3IIg). The research results show that the electric field near the powered electric field is higher than at the edge of the discharge. These experimental results are very important for numerical study and industrial application of the surface discharge.

Thermionic reactor power conditioner design for nuclear electric propulsion.

NASA Technical Reports Server (NTRS)

Jacobsen, A. S.; Tasca, D. M.

1971-01-01

Consideration of the effects of various thermionic reactor parameters and requirements upon spacecraft power conditioning design. A basic spacecraft is defined using nuclear electric propulsion, requiring approximately 120 kWe. The interrelationships of reactor operating characteristics and power conditioning requirements are discussed and evaluated, and the effects on power conditioner design and performance are presented.

Elemental Composition of the Powder Particles Produced by Electric Discharge Dispersion of the Wastes of a VK8 Hard Alloy

NASA Astrophysics Data System (ADS)

Latypov, R. A.; Ageev, E. V.; Latypova, G. R.; Altukhov, A. Yu.; Ageeva, E. V.

2017-12-01

The powder fabricated by electric discharge dispersion of the wastes of a VK8 hard alloy is studied by electron-probe microanalysis. This powder formed by electric discharge dispersion in kerosene mainly contains tungsten and carbon and has low contents of oxygen, cobalt, and iron.

Lightning and middle atmospheric discharges in the atmosphere

NASA Astrophysics Data System (ADS)

Siingh, Devendraa; Singh, R. P.; Kumar, Sarvan; Dharmaraj, T.; Singh, Abhay K.; Singh, Ashok K.; Patil, M. N.; Singh, Shubha

2015-11-01

Recent development in lightning discharges including transient luminous events (TLEs) and global electric circuit are discussed. Role of solar activity, convective available potential energy, surface temperature and difference of land-ocean surfaces on convection process are discussed. Different processes of discharge initiation are discussed. Events like sprites and halos are caused by the upward quasi-electrostatic fields associated with intense cloud-to-ground discharges while jets (blue starter, blue jet, gigantic jet) are caused by charge imbalance in thunderstorm during lightning discharges but they are not associated with a particular discharge flash. Elves are generated by the electromagnetic pulse radiated during lightning discharges. The present understanding of global electric circuit is also reviewed. Relation between lightning activity/global electric circuit and climate is discussed.

Effects of Electric Discharge Plasma Treatment on the Thermal Conductivity of Polymer-Metal Nitride/Carbide Composites

NASA Astrophysics Data System (ADS)

Parali, Levent; Kurbanov, Mirza A.; Bayramov, Azad A.; Tatardar, Farida N.; Sultanakhmedova, Ramazanova I.; Xanlar, Huseynova Gulnara

2015-11-01

High-density polymer composites with semiconductor or dielectric fillers such as aluminum nitride (AIN), aluminum oxide (Al2O3), titanium carbide (TiC), titanium nitride (TiN), boron nitride (BN), silicon nitride (Si3N4), and titanium carbonitride (TiCN) were prepared by the hot pressing method. Each powder phase of the composites was exposed to an electric discharge plasma process before composite formation. The effects of the electric discharge plasma process and the filler content (volume fraction) on the thermal conductivity, volt-ampere characteristics, thermally stimulated depolarization current, as well as electrical and mechanical strength were investigated. The results of the study indicate that, with increasing filler volume fraction, the thermal conductivity of the samples also increased. Furthermore, the thermal conductivity, and electrophysical and mechanical properties of the high-density polyethylene + 70% BN composite modified using the electric discharge plasma showed improvement when compared with that without electric discharge plasma treatment.

Plasma rotation by electric and magnetic fields in a discharge cylinder

NASA Technical Reports Server (NTRS)

Wilhelm, H. E.; Hong, S. H.

1977-01-01

A theoretical model for an electric discharge consisting of a spatially diverging plasma sustained electrically between a small ring cathode and a larger ring anode in a cylindrical chamber with an axial magnetic field is developed to study the rotation of the discharge plasma in the crossed electric and magnetic fields. The associated boundary-value problem for the coupled partial differential equations which describe the electric potential and the plasma velocity fields is solved in closed form. The electric field, current density, and velocity distributions are discussed in terms of the Hartmann number and the Hall coefficient. As a result of Lorentz forces, the plasma rotates with speeds as high as 1 million cm/sec around its axis of symmetry at typical conditions. As an application, it is noted that rotating discharges of this type could be used to develop a high-density plasma-ultracentrifuge driven by j x B forces, in which the lighter (heavier) ion and atom components would be enriched in (off) the center of the discharge cylinder.

Combustion flame-plasma hybrid reactor systems, and chemical reactant sources

DOEpatents

Kong, Peter C

2013-11-26

Combustion flame-plasma hybrid reactor systems, chemical reactant sources, and related methods are disclosed. In one embodiment, a combustion flame-plasma hybrid reactor system comprising a reaction chamber, a combustion torch positioned to direct a flame into the reaction chamber, and one or more reactant feed assemblies configured to electrically energize at least one electrically conductive solid reactant structure to form a plasma and feed each electrically conductive solid reactant structure into the plasma to form at least one product is disclosed. In an additional embodiment, a chemical reactant source for a combustion flame-plasma hybrid reactor comprising an elongated electrically conductive reactant structure consisting essentially of at least one chemical reactant is disclosed. In further embodiments, methods of forming a chemical reactant source and methods of chemically converting at least one reactant into at least one product are disclosed.

Study of carbon dioxide gas treatment based on equations of kinetics in plasma discharge reactor

NASA Astrophysics Data System (ADS)

Abedi-Varaki, Mehdi

2017-08-01

Carbon dioxide (CO2) as the primary greenhouse gas, is the main pollutant that is warming earth. CO2 is widely emitted through the cars, planes, power plants and other human activities that involve the burning of fossil fuels (coal, natural gas and oil). Thus, there is a need to develop some method to reduce CO2 emission. To this end, this study investigates the behavior of CO2 in dielectric barrier discharge (DBD) plasma reactor. The behavior of different species and their reaction rates are studied using a zero-dimensional model based on equations of kinetics inside plasma reactor. The results show that the plasma reactor has an effective reduction on the CO2 density inside the reactor. As a result of reduction in the temporal variations of reaction rate, the speed of chemical reactions for CO2 decreases and very low concentration of CO2 molecules inside the plasma reactor is generated. The obtained results are compared with the existing experimental and simulation findings in the literature.

Water dissociation in a radio-frequency electromagnetic field with ex situ electrodes—process characterization

NASA Astrophysics Data System (ADS)

Schneider, Jens; Holzer, Frank; Kraus, Markus; Kopinke, Frank-Dieter; Roland, Ulf

2013-02-01

A new type of water dissociation at ambient pressure initiated by the irradiation of aqueous electrolytes using an electromagnetic field with a frequency of 13.56 MHz is described in this study. A special reactor design allows the use of ex situ electrodes to form in situ electrical discharges in water vapour bubbles. The observed formation of molecular hydrogen (H2) and oxygen (O2) combined with the emission of light (‘burning water’ phenomenon) originates from a non-thermal plasma in water vapour bubbles. The influences of type of electrolyte, its concentration, pH value and external RF voltage on the gas formation rate as well as on the gas composition are presented.

Electro-Hydrodynamics and Kinetic Modeling of Dry and Humid Air Flows Activated by Corona Discharges

NASA Astrophysics Data System (ADS)

P. Sarrette, J.; Eichwald, O.; Marchal, F.; Ducasse, O.; Yousfi, M.

2016-05-01

The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor (ACDR) powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The study compares the results obtained in dry air and in air mixed with a small amount of water vapour (humid air). The simulation involves the electro-dynamics, chemical kinetics and neutral gas hydrodynamics phenomena that influence the kinetics of the chemical species transformation. Each discharge lasts about one hundred of a nanosecond while the post-discharge occurring between two successive discharges lasts one hundred of a microsecond. The ACDR is crossed by a lateral dry or humid air flow initially polluted with 400 ppm of NO. After 5 ms, the time corresponding to the occurrence of 50 successive discharge/post-discharge phases, a higher NO removal rate and a lower ozone production rate are found in humid air. This change is due to the presence of the HO2 species formed from the H primary radical in the discharge zone.

Electro-hydrodynamics and kinetic modelling of polluted air flow activated by multi-tip-to-plane corona discharge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meziane, M.; Eichwald, O.; Ducasse, O.

The present paper is devoted to the 2D simulation of an Atmospheric Corona Discharge Reactor (ACDR) involving 10 pins powered by a DC high voltage and positioned 7 mm above a grounded metallic plane. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The simulation involves the electro-dynamic, chemical kinetic, and neutral gas hydrodynamic phenomena that influence the kinetics of the chemical species transformation. Each discharge stage (including the primary and the secondary streamers development and the resulting thermal shock) lasts about one hundred nanoseconds while the post-dischargemore » stages occurring between two successive discharge phases last one hundred microseconds. The ACDR is crossed by a lateral air flow including 400 ppm of NO. During the considered time scale of 10 ms, one hundred discharge/post-discharge cycles are simulated. The simulation involves the radical formation and thermal exchange between the discharges and the background gas. The results show how the successive discharges activate the flow gas and how the induced turbulence phenomena affect the redistribution of the thermal energy and the chemical kinetics inside the ACDR.« less

High-altitude electrical discharges associated with thunderstorms and lightning

NASA Astrophysics Data System (ADS)

Liu, Ningyu; McHarg, Matthew G.; Stenbaek-Nielsen, Hans C.

2015-12-01

The purpose of this paper is to introduce electrical discharge phenomena known as transient luminous events above thunderstorms to the lightning protection community. Transient luminous events include the upward electrical discharges from thunderstorms known as starters, jets, and gigantic jets, and electrical discharges initiated in the lower ionosphere such as sprites, halos, and elves. We give an overview of these phenomena with a focus on starters, jets, gigantic jets, and sprites, because similar to ordinary lightning, streamers and leaders are basic components of these four types of transient luminous events. We present a few recent observations to illustrate their main properties and briefly review the theories. The research in transient luminous events has not only advanced our understanding of the effects of thunderstorms and lightning in the middle and upper atmosphere, but also improved our knowledge of basic electrical discharge processes critical for sparks and lightning.

Application of LIF technique for the space- and time-resolved monitoring of pollutant gas decomposition in nonthermal plasma reactors

NASA Astrophysics Data System (ADS)

Mizeraczyk, Jerzy; Ohkubo, Toshikazu; Kanazawa, Seiji; Kocik, Marek

2003-10-01

Laser-induced fluorescence (LIF) technique aided by intensified CCD light signal detection and fast digital image processing is demonstrated to be a useful diagnostic method for in-situ observation of the discharge-induced plasma-chemistry processes responsible for NOx(NO + NO2) decomposition occurring in non-thermal plasma reactors. In this paper a method and results of the LIF measurement of two-dimensional distribution of the ground-state NO molecule density inside a DC positive streamer corona reactor during NO removal from a flue gas simulator [air/NO(up to 300 ppm)] are presented. Either a needle-to-plate or nozzle-to-plate electrode system, having an electrode gap of 30-50 mm was used for generating the corona discharge in the reactor. The LIF monitoring of NO molecules was carried out under the steady-state DC corona discharge condition. The laser-induced fluorescence on the transition NO X2Π(v"=0)<--A2Σ+(v'=0) at λ=226nm was chosen for monitoring ground-state NO molecules in the reactor. This transition was induced by irradiation of the NO molecules with UV laser pulses generated by a laser system consisted of a XeF excimer laser, dye laser and BBO crystal. The laser pulses from the XeF excimer laser (Lambda Physik, Complex 150, λ=351 nm) pumped the dye laser (Lambda Physik, Scanmate) with Coumarin 47 as a dye, which generated the laser beam of a wavelength turned around λ=450 nm. Then, the tuned dye laser beam pumped the BBO crystal in which the second harmonic radiation of a wavelength correspondingly tuned around λ=226 nm was generated. The 226-nm UV laser pulses of energy of 0.8-2 mJ and duration of about 20 ns were transformed into the form of the so-called laser sheet (width of 1 mm, height of 30-50 mm) which passed between the electrodes through the operating gas. The obtained results, presented in the form of images, which illustrated the two-dimensional distributions of NO molecule concentration in the non-thermal reactor, showed that the corona discharge-induced removal of NO molecules occurred not only in the vicinity of the plasma region formed by the corona discharge-induced removal of NO molecules occurred not only in the vicinity of the plasma region formed by the corona streamers and in the downstream region of the reactor but also in the upstream region of the reactor, i.e. before the flue gas simulator has entered the plasma region. This information obtained owing to the LIF technique, is important for the understanding of the plasma-chemistry processes responsible for NOx decomposition in non-thermal plasma reactors and for optimising their performance.

Uranium to Electricity: The Chemistry of the Nuclear Fuel Cycle

ERIC Educational Resources Information Center

Settle, Frank A.

2009-01-01

The nuclear fuel cycle consists of a series of industrial processes that produce fuel for the production of electricity in nuclear reactors, use the fuel to generate electricity, and subsequently manage the spent reactor fuel. While the physics and engineering of controlled fission are central to the generation of nuclear power, chemistry…

Response of nickel to zinc cells to electric vehicle chopper discharge waveforms

NASA Technical Reports Server (NTRS)

Cataldo, R. L.

1981-01-01

The preliminary results of simulated electric vehicle chopper controlled discharge of a Nickel/Zinc battery shows delivered energy increases of 5 to 25 percent compared to constant current discharges of the same average current. The percentage increase was a function of chopper frequency, the ratio of peak to average current, and the magnitude of the discharge current. Because the chopper effects are of a complex nature, electric vehicle battery/speed controller interaction must be carefully considered in vehicle design to optimize battery performance.

High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion

NASA Technical Reports Server (NTRS)

Juhasz, Albert J.; Sawicki, Jerzy T.

2003-01-01

For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a partial energy conversion system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.

High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion

NASA Astrophysics Data System (ADS)

Juhasz, Albert J.; Sawicki, Jerzy T.

2004-02-01

For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a ``partial energy conversion'' system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.

Nuclear Reactors. Revised.

ERIC Educational Resources Information Center

Hogerton, John F.

This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Among the topics discussed are: How Reactors Work; Reactor Design; Research, Teaching, and Materials Testing; Reactors (Research, Teaching and Materials); Production Reactors; Reactors for Electric Power…

Condensation model for the ESBWR passive condensers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Revankar, S. T.; Zhou, W.; Wolf, B.

2012-07-01

In the General Electric's Economic simplified boiling water reactor (GE-ESBWR) the passive containment cooling system (PCCS) plays a major role in containment pressure control in case of an loss of coolant accident. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure following a design basis accident. There are three PCCS condensation modes depending on the containment pressurization due to coolant discharge; complete condensation, cyclic venting and flow through mode. The present work reviews the models and presents model predictive capability along with comparison with existing data frommore » separate effects test. The condensation models in thermal hydraulics code RELAP5 are also assessed to examine its application to various flow modes of condensation. The default model in the code predicts complete condensation well, and basically is Nusselt solution. The UCB model predicts through flow well. None of condensation model in RELAP5 predict complete condensation, cyclic venting, and through flow condensation consistently. New condensation correlations are given that accurately predict all three modes of PCCS condensation. (authors)« less

Characterization of surface dielectric barrier discharge influenced by intermediate frequency for ozone production

NASA Astrophysics Data System (ADS)

Abdelaziz, Ayman A.; Ishijima, Tatsuo; Seto, Takafumi; Osawa, Naoki; Wedaa, Hassan; Otani, Yoshio

2016-06-01

The aim of this study is to investigate the effect of the intermediate frequency (1-10 kHz) of the sinusoidal driving voltage on the characteristics of a developed surface dielectric barrier discharge (SDBD)-based reactor having spikes on its discharge electrode. Moreover, its influence on the production of ozone and nitrogen oxide byproducts is evaluated. The results show that SDBD is operated in the filamentary mode at all the frequencies. Nevertheless, the pulses of the discharge current at high frequencies are much denser and have higher amplitudes than those at low frequencies. The analysis of the power consumed in the reactor shows that a small portion of the input power is dissipated in the dielectric material of SDBD source, whereas the major part of the power is consumed in the plasma discharge. The results of the ozone production show that higher frequencies have a slightly adverse effect on the ozone production at relatively high energy density values, where the ozone concentration is slightly decreased when the frequency is increased at the same energy density. The temperature of the discharge channels and gas is not a crucial factor for the decomposition of ozone in this reactor, while the results of the measurements of nitrogen oxides characteristics indicate that the formation of NO and NO2 has a significant adverse effect on the production efficiency of ozone due to their oxidation to another nitrogen oxides and their catalytic effect.

Wire electric-discharge machining and other fabrication techniques

NASA Technical Reports Server (NTRS)

Morgan, W. H.

1983-01-01

Wire electric discharge machining and extrude honing were used to fabricate a two dimensional wing for cryogenic wind tunnel testing. Electric-discharge cutting is done with a moving wire electrode. The cut track is controlled by means of a punched-tape program and the cutting feed is regulated according to the progress of the work. Electric-discharge machining involves no contact with the work piece, and no mechanical force is exerted. Extrude hone is a process for honing finish-machined surfaces by the extrusion of an abrasive material (silly putty), which is forced through a restrictive fixture. The fabrication steps are described and production times are given.

USSR Report, Energy, No. 147.

DTIC Science & Technology

1983-05-18

based on low-temperature reactors ; atomic heat and electric power stations (ATETs); The restructuring of the energy balance for the 1980-2000 period...ASPT) based on low-temperature reactors ; atomic heat and electric power stations (TETs); industrial atomic power stations (AETS) based on high-temper...ature reactors ) and high-efficiency long-distance heat transport (in conjunc- tion with high-temperature nuclear power sources: ASDT). The

The Birth of Nuclear-Generated Electricity

DOE R&D Accomplishments Database

1999-09-01

The Experimental Breeder Reactor-I (EBR-I), built in Idaho in 1949, generated the first usable electricity from nuclear power on December 20, 1951. More importantly, the reactor was used to prove that it was possible to create more nuclear fuel in the reactor than it consumed during operation -- fuel breeding. The EBR-I facility is now a National Historic Landmark open to the public.

Synergistic responses of superficial chemistry and micro topography of titanium created by wire-type electric discharge machining.

PubMed

Kataoka, Yu; Tamaki, Yukimichi; Miyazaki, Takashi

2011-01-01

Wire-type electric discharge machining has been applied to the manufacture of endosseous titanium implants as this computer associated technique allows extremely accurate complex sample shaping with an optimal micro textured surface during the processing. Since the titanium oxide layer is sensitively altered by each processing, the authors hypothesized that this technique also up-regulates biological responses through the synergistic effects of the superficial chemistry and micro topography. To evaluate the respective in vitro cellular responses on the superficial chemistry and micro topography of titanium surface processed by wire-type electric discharge, we used titanium-coated epoxy resin replica of the surface. An oxide layer on the titanium surface processed by wire-type electric discharge activated the initial responses of osteoblastic cells through an integrin-mediated mechanism. Since the mRNA expression of ALP on those replicas was up-regulated compared to smooth titanium samples, the micro topography of a titanium surface processed by wire-type electric discharge promotes the osteogenic potential of cells. The synergistic response of the superficial chemistry and micro topography of titanium processed by wire-type electric discharge was demonstrated in this study.

Susceptibility constants of airborne bacteria to dielectric barrier discharge for antibacterial performance evaluation.

PubMed

Park, Chul Woo; Hwang, Jungho

2013-01-15

Dielectric barrier discharge (DBD) is a promising method to remove contaminant bioaerosols. The collection efficiency of a DBD reactor is an important factor for determining a reactor's removal efficiency. Without considering collection, simply defining the inactivation efficiency based on colony counting numbers for DBD as on and off may lead to overestimation of the inactivation efficiency of the DBD reactor. One-pass removal tests of bioaerosols were carried out to deduce the inactivation efficiency of the DBD reactor using both aerosol- and colony-counting methods. Our DBD reactor showed good performance for removing test bioaerosols for an applied voltage of 7.5 kV and a residence time of 0.24s, with η(CFU), η(Number), and η(Inactivation) values of 94%, 64%, and 83%, respectively. Additionally, we introduce the susceptibility constant of bioaerosols to DBD as a quantitative parameter for the performance evaluation of a DBD reactor. The modified susceptibility constant, which is the ratio of the susceptibility constant to the volume of the plasma reactor, has been successfully demonstrated for the performance evaluation of different sized DBD reactors under different DBD operating conditions. Our methodology will be used for design optimization, performance evaluation, and prediction of power consumption of DBD for industrial applications. Copyright © 2012 Elsevier B.V. All rights reserved.

Methane and hydrogen sulfide emissions in UASB reactors treating domestic wastewater.

PubMed

Souza, C L; Chernicharo, C A L; Melo, G C B

2012-01-01

The release of CH(4) and H(2)S in UASB reactors was evaluated with the aim to quantify the emissions from the liquid surfaces (three-phase separator and settler compartment) and also from the reactor's discharge hydraulic structures. The studies were carried out in two pilot- (360 L) and one demo-scale (14 m(3)) UASB reactors treating domestic wastewater. As expected, the release rates were much higher across the gas/liquid interfaces of the three-phase separators (5.4-9.7 kg CH(4) m(-2) d(-1) and 23.0-35.8 g S m(-2) d(-1)) as compared with the quiescent settler surfaces (11.0-17.8 g CH(4) m(-2) d(-1) and 0.21 to 0.37 g S m(-2) d(-1)). The decrease of dissolved methane and dissolved hydrogen sulfide was very large in the discharging hydraulic structures very close to the reactor (>60 and >80%, respectively), largely due to the loss to the atmosphere, indicating that the concentration of these compounds will probably fall to values close to zero in the near downstream structures. The emission factors due to the release of dissolved methane in the discharge structure amounted to around 0.040 g CH(4) g COD(infl)(-1) and 0.060 g CH(4) g COD(rem)(-1), representing around 60% of the methane collected in the three-phase separator.

NEUTRONIC REACTOR CHARGING AND DISCHARGING

DOEpatents

Zinn, W.H.

1959-07-14

A method and arrangement is presented for removing a fuel element from a neutronic reactor tube through which a liquid coolant is being circulaled. The fuel element is moved into a section of the tube beyond the reactor proper, and then the coolant in the tube between the fuel element and the reactor proper is frozen, so that the fuel element may be removed from the tube without loss of the coolant therein. The method is particularly useful in the case of a liquid metal- cooled reactor.

Dual-mode, high energy utilization system concept for mars missions

NASA Astrophysics Data System (ADS)

El-Genk, Mohamed S.

2000-01-01

This paper describes a dual-mode, high energy utilization system concept based on the Pellet Bed Reactor (PeBR) to support future manned missions to Mars. The system uses proven Closed Brayton Cycle (CBC) engines to partially convert the reactor thermal power to electricity. The electric power generated is kept the same during the propulsion and the power modes, but the reactor thermal power in the former could be several times higher, while maintaining the reactor temperatures almost constant. During the propulsion mode, the electric power of the system, minus ~1-5 kWe for house keeping, is used to operate a Variable Specific Impulse Magnetoplasma Rocket (VASIMR). In addition, the reactor thermal power, plus more than 85% of the head load of the CBC engine radiators, are used to heat hydrogen. The hot hydrogen is mixed with the high temperature plasma in a VASIMR to provide both high thrust and Isp>35,000 N.s/kg, reducing the travel time to Mars to about 3 months. The electric power also supports surface exploration of Mars. The fuel temperature and the inlet temperatures of the He-Xe working fluid to the nuclear reactor core and the CBC turbine are maintained almost constant during both the propulsion and power modes to minimize thermal stresses. Also, the exit temperature of the He-Xe from the reactor core is kept at least 200 K below the maximum fuel design temperature. The present system has no single point failure and could be tested fully assembled in a ground facility using electric heaters in place of the nuclear reactor. Operation and design parameters of a 40-kWe prototype are presented and discussed to illustrate the operation and design principles of the proposed system. .

Response of lead-acid batteries to chopper-controlled discharge. [for electric vehicles

NASA Technical Reports Server (NTRS)

Cataldo, R. L.

1978-01-01

The results of tests on an electric vehicle battery, using a simulated electric vehicle chopper-speed controller, show energy output losses up to 25 percent compared to constant current discharges at the same average current of 100 A. However, an energy output increase of 22 percent is noticed at the 200 A average level and 44 percent increase at the 300 A level using pulse discharging. Because of these complex results, electric vehicle battery/speed controller interactions must be considered in vehicle design.

ETR ELECTRICAL BUILDING, TRA648, INTERIOR. SWITCHGEAR. INL NEGATIVE NO. 563794. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR ELECTRICAL BUILDING, TRA-648, INTERIOR. SWITCHGEAR. INL NEGATIVE NO. 56-3794. Jack L. Anderson, Photographer, 11/26/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

ETR ELECTRICAL BUILDING, TRA648. BATTERY ROOM. INL NEGATIVE NO. 563785. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR ELECTRICAL BUILDING, TRA-648. BATTERY ROOM. INL NEGATIVE NO. 56-3785. Jack L. Anderson, Photographer, 11/26/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Dielectric barrier discharges: progress on plasma sources and on the understanding of regimes and single filaments

NASA Astrophysics Data System (ADS)

Brandenburg, Ronny

2017-05-01

Dielectric barrier discharges (DBDs) are plasmas generated in configurations with an insulating (dielectric) material between the electrodes which is responsible for a self-pulsing operation. DBDs are a typical example of nonthermal atmospheric or normal pressure gas discharges. Initially used for the generation of ozone, they have opened up many other fields of application. Therefore DBDs are a relevant tool in current plasma technology as well as an object for fundamental studies. Another motivation for further research is the fact that so-called partial discharges in insulated high voltage systems are special types of DBDs. The breakdown processes, the formation of structures, and the role of surface processes are currently under investigation. This review is intended to give an update to the already existing literature on DBDs considering the research and development within the last two decades. The main principles and different modes of discharge generation are summarized. A collection of known as well as special electrode configurations and reactor designs will be presented. This shall demonstrate the different and broad possibilities, but also the similarities and common aspects of devices for different fields of applications explored within the last years. The main part is devoted to the progress on the investigation of different aspects of breakdown and plasma formation with the focus on single filaments or microdischarges. This includes a summary of the current knowledge on the electrical characterization of filamentary DBDs. In particular, the recent new insights on the elementary volume and surface memory mechanisms in these discharges will be discussed. An outlook for the forthcoming challenges on research and development will be given.

76 FR 39922 - Office of New Reactors; Proposed Revision 4 to Standard Review Plan Section 8.1 on Electric Power...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-07

... the proposed Revision 4 to Standard Review Plan Section 8.1 on ``Electric Power-- Introduction.'' The... NUCLEAR REGULATORY COMMISSION [NRC-2011-0119] Office of New Reactors; Proposed Revision 4 to Standard Review Plan Section 8.1 on Electric Power--Introduction, Correction AGENCY: Nuclear Regulatory...

Application of the Enabler to nuclear electric propulsion

NASA Astrophysics Data System (ADS)

Pierce, Bill L.

This paper describes a power system concept that provides the electric power for a baseline electric propulsion system for a piloted mission to Mars. A 10-MWe space power system is formed by coupling an Enabler reactor with a simple non-recuperated closed Brayton cycle. The Enabler reactor is a gas-cooled reactor based on proven reactor technology developed under the NERVA/Rover programs. The selected power cycle, which uses a helium-xenon mixture at 1920 K at the turbine inlet, is diagramed and described. The specific mass of the power system over the power range from 5 to 70 MWe is given. The impact of operating life on the specific mass of a 10-MWe system is also shown.

Slope and amplitude asymmetry effects on low frequency capacitively coupled carbon tetrafluoride plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bruneau, B., E-mail: bastien.bruneau@polytechnique.edu; Johnson, E.; Korolov, I.

2016-04-28

We report investigations of capacitively coupled carbon tetrafluoride (CF{sub 4}) plasmas excited with tailored voltage waveforms containing up to five harmonics of a base frequency of 5.5 MHz. The impact of both the slope asymmetry, and the amplitude asymmetry, of these waveforms on the discharge is examined by combining experiments with particle-in-cell simulations. For all conditions studied herein, the discharge is shown to operate in the drift-ambipolar mode, where a comparatively large electric field in the plasma bulk (outside the sheaths) is the main mechanism for electron power absorption leading to ionization. We show that both types of waveform asymmetries stronglymore » influence the ion energy at the electrodes, with the particularity of having the highest ion flux on the electrode where the lowest ion energy is observed. Even at the comparatively high pressure (600 mTorr) and low fundamental frequency of 5.5 MHz used here, tailoring the voltage waveforms is shown to efficiently create an asymmetry of both the ion energy and the ion flux in geometrically symmetric reactors.« less

MTR BASEMENT. GENERAL ELECTRIC CONTROL CONSOLE FOR AIRCRAFT NUCLEAR PROPULSION ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR BASEMENT. GENERAL ELECTRIC CONTROL CONSOLE FOR AIRCRAFT NUCLEAR PROPULSION EXPERIMENT NO. 1. INL NEGATIVE NO. 6510. Unknown Photographer, 9/29/1959 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Jackson, Todd, and the concept of "discharge" in epilepsy.

PubMed

Reynolds, Edward H

2007-11-01

To explore the historical origins of the modern concept of electrical discharges in the brain in epilepsy. I have examined the writings of Hughlings Jackson (1835-1911) and Robert Bentley Todd (1809-1860), especially their Lumleian Lectures on convulsive disorders to the Royal College of Physicians of 1890 and 1849, respectively; and also the influence of Herbert Spencer (1820-1903) on the former and Michael Faraday (1791-1867) on the latter. Contrary to the widely taught view that Jackson was the first to propose electrical discharges in epilepsy it is clear that the discharges suggested by Jackson, influenced by the evolutionary philosopher, Herbert Spencer, were chemical, based on katabolism and anabolism. Jackson had no understanding or proposal based on physics or electricity. On the other hand, Todd had earlier proposed and described electrical concepts of discharges in epilepsy, influenced by his contemporary and colleague in London, Michael Faraday, who at the time was laying the foundations of our modern understanding of electricity and magnetism. Todd and Faraday saw "nervous polarity" as another polar force interchangeable with the polar forces of electricity and magnetism.

The benefits of a fast reactor closed fuel cycle in the UK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gregg, R.; Hesketh, K.

2013-07-01

The work has shown that starting a fast reactor closed fuel cycle in the UK, requires virtually all of Britain's existing and future PWR spent fuel to be reprocessed, in order to obtain the plutonium needed. The existing UK Pu stockpile is sufficient to initially support only a modest SFR 'closed' fleet assuming spent fuel can be reprocessed shortly after discharge (i.e. after two years cooling). For a substantial fast reactor fleet, most Pu will have to originate from reprocessing future spent PWR fuel. Therefore, the maximum fast reactor fleet size will be limited by the preceding PWR fleet size,more » so scenarios involving fast reactors still require significant quantities of uranium ore indirectly. However, once a fast reactor fuel cycle has been established, the very substantial quantities of uranium tails in the UK would ensure there is sufficient material for several centuries. Both the short and long term impacts on a repository have been considered in this work. Over the short term, the decay heat emanating from the HLW and spent fuel will limit the density of waste within a repository. For scenarios involving fast reactors, the only significant heat bearing actinide content will be present in the final cores, resulting in a 50% overall reduction in decay energy deposited within the repository when compared with an equivalent open fuel cycle. Over the longer term, radiological dose becomes more important. Total radiotoxicity (normalised by electricity generated) is lower for scenarios with Pu recycle after 2000 years. Scenarios involving fast reactors have the lowest radiotoxicity since the quantities of certain actinides (Np, Pu and Am) eventually stabilise. However, total radiotoxicity as a measure of radiological risk does not account for differences in radionuclide mobility once in repository. Radiological dose is dominated by a small number of fission products so is therefore not affected significantly by reactor type or recycling strategy (since the fission product will primarily be a function of nuclear energy generated). However, by reprocessing spent fuel, it is possible to immobilise the fission product in a more suitable waste form that has far more superior in-repository performance. (authors)« less

Characterization of electrical discharges on Teflon dielectrics used as spacecraft thermal control

NASA Technical Reports Server (NTRS)

Yadlowsky, E. J.; Hazelton, R. C.; Churchill, R. J.

1979-01-01

The dual effects of system degradation and reduced life of synchronous-orbit satellites as a result of differential spacecraft charging underscore the need for a clearer understanding of the prevailing electrical discharge phenomena. In a laboratory simulation, the electrical discharge current, surface voltage, emitted particle fluxes, and photo-emission associated with discharge events on electron beam irradiated silver-backed Teflon samples were measured. Sample surface damage was examined with optical and electron beam microscopes. The results are suggestive of a model in which the entire sample surface is discharged by lateral sub-surface currents flowing from a charge deposition layer through a localized discharge channel to the back surface of the sample. The associated return current pulse appears to have a duration which may be a signature by which different discharge processes may be characterized.

Process Properties of Electronic High Voltage Discharges Triggered by Ultra-short Pulsed Laser Filaments

NASA Astrophysics Data System (ADS)

Cvecek, Kristian; Gröschel, Benjamin; Schmidt, Michael

Remote processing of metallic workpieces by techniques based on electric arc discharge or laser irradiation for joining or cutting has a long tradition and is still being intensively investigated in present-day research. In applications that require high power processing, both approaches exhibit certain advantages and disadvantages that make them specific for a given task. While several hybrid approaches exist that try to combine the benefits of both techniques, none were as successful in providing a fixed electric discharge direction as discharges triggered by plasma filaments generated by ultra-short pulsed lasers. In this work we investigate spatial and temporal aspects of laser filament guided discharges and give an upper time delay between the filament creation and the electrical build-up of a dischargeable voltage for a successful filament triggered discharge.

Lightning Discharges to Aircraft and Associated Meteorological Conditions

NASA Technical Reports Server (NTRS)

Harrison, L P

1946-01-01

A summary is given of information on atmospheric electrical discharges to aircraft and associated meteorological conditions. Information is given that is designed to give a fairly comprehensive view of the underlying principles of meteorology and atmospheric electricity. Of special interest to pilots are lists of procedures of flight conduct and aircraft maintenance recommended foe avoiding or minimizing the hazards of disruptive electrical discharges and other severe conditions near thunderstorms.

Pulsed electrical discharge in gas bubbles in water

NASA Astrophysics Data System (ADS)

Gershman, Sophia

A phenomenological picture of pulsed electrical discharge in gas bubbles in water is produced by combining electrical, spectroscopic, and imaging methods. The discharge is generated by applying one microsecond long 5 to 20 kilovolt pulses between the needle and disk electrodes submerged in water. A gas bubble is generated at the tip of the needle electrode. The study includes detailed experimental investigation of the discharge in argon bubbles and a brief look at the discharge in oxygen bubbles. Imaging, electrical characteristics, and time-resolved optical emission data point to a fast streamer propagation mechanism and formation of a plasma channel in the bubble. Spectroscopic methods based on line intensity ratios and Boltzmann plots of line intensities of argon, atomic hydrogen, and argon ions and the examination of molecular emission bands from molecular nitrogen and hydroxyl radicals provide evidence of both fast beam-like electrons and slow thermalized ones with temperatures of 0.6 -- 0.8 electron-volts. The collisional nature of plasma at atmospheric pressure affects the decay rates of optical emission. Spectroscopic study of rotational-vibrational bands of hydroxyl radical and molecular nitrogen gives vibrational and rotational excitation temperatures of the discharge of about 0.9 and 0.1 electron-volt, respectively. Imaging and electrical evidence show that discharge charge is deposited on the bubble wall and water serves as a dielectric barrier for the field strength and time scales of this experiment. Comparing the electrical and imaging information for consecutive pulses applied at a frequency of 1 Hz indicates that each discharge proceeds as an entirely new process with no memory of the previous discharge aside from long-lived chemical species, such as ozone and oxygen. Intermediate values for the discharge gap and pulse duration, low repetition rate, and unidirectional character of the applied voltage pulses make the discharge process here unique compared to the traditional corona or dielectric barrier discharges. These conditions make the experimental evidence presented in this work valuable for the advancement of modeling and the theoretical understanding of the discharge in bubbles in water.

Chapter 8: Plasma operation and control

NASA Astrophysics Data System (ADS)

ITER Physics Expert Group on Disruptions, Control, Plasma, and MHD; ITER Physics Expert Group on Energetic Particles, Heating, Current and Drive; ITER Physics Expert Group on Diagnostics; ITER Physics Basis Editors

1999-12-01

Wall conditioning of fusion devices involves removal of desorbable hydrogen isotopes and impurities from interior device surfaces to permit reliable plasma operation. Techniques used in present devices include baking, metal film gettering, deposition of thin films of low-Z material, pulse discharge cleaning, glow discharge cleaning, radio frequency discharge cleaning, and in situ limiter and divertor pumping. Although wall conditioning techniques have become increasingly sophisticated, a reactor scale facility will involve significant new challenges, including the development of techniques applicable in the presence of a magnetic field and of methods for efficient removal of tritium incorporated into co-deposited layers on plasma facing components and their support structures. The current status of various approaches is reviewed, and the implications for reactor scale devices are summarized. Creation and magnetic control of shaped and vertically unstable elongated plasmas have been mastered in many present tokamaks. The physics of equilibrium control for reactor scale plasmas will rely on the same principles, but will face additional challenges, exemplified by the ITER/FDR design. The absolute positioning of outermost flux surface and divertor strike points will have to be precise and reliable in view of the high heat fluxes at the separatrix. Long pulses will require minimal control actions, to reduce accumulation of AC losses in superconducting PF and TF coils. To this end, more complex feedback controllers are envisaged, and the experimental validation of the plasma equilibrium response models on which such controllers are designed is encouraging. Present simulation codes provide an adequate platform on which equilibrium response techniques can be validated. Burning plasmas require kinetic control in addition to traditional magnetic shape and position control. Kinetic control refers to measures controlling density, rotation and temperature in the plasma core as well as in plasma periphery and divertor. The planned diagnostics (Chapter 7) serve as sensors for kinetic control, while gas and pellet fuelling, auxiliary power and angular momentum input, impurity injection, and non-inductive current drive constitute the control actuators. For example, in an ignited plasma, core density controls fusion power output. Kinetic control algorithms vary according to the plasma state, e.g. H- or L-mode. Generally, present facilities have demonstrated the kinetic control methods required for a reactor scale device. Plasma initiation - breakdown, burnthrough and initial current ramp - in reactor scale tokamaks will not involve physics differing from that found in present day devices. For ITER, the induced electric field in the chamber will be ~0.3V· m-1 - comparable to that required by breakdown theory but somewhat smaller than in present devices. Thus, a start-up 3MW electron cyclotron heating system will be employed to assure burnthrough. Simulations show that plasma current ramp up and termination in a reactor scale device can follow procedures developed to avoid disruption in present devices. In particular, simulations remain in the stable area of the li-q plane. For design purposes, the resistive V·s consumed during initiation is found, by experiments, to follow the Ejima expression, 0.45μ0 RIp. Advanced tokamak control has two distinct goals. First, control of density, auxiliary power, and inductive current ramping to attain reverse shear q profiles and internal transport barriers, which persist until dissipated by magnetic flux diffusion. Such internal transport barriers can lead to transient ignition. Second, combined use poloidal field shape control with non-inductive current drive and NBI angular momentum injection to create and control steady state, high bootstrap fraction, reverse shear discharges. Active n = 1 magnetic feedback and/or driven rotation will be required to suppress resistive wall modes for steady state plasmas that must operate in the wall stabilized regime for reactor levels of β >= 0.03.

COST FUNCTION STUDIES FOR POWER REACTORS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heestand, J.; Wos, L.T.

1961-11-01

A function to evaluate the cost of electricity produced by a nuclear power reactor was developed. The basic equation, revenue = capital charges + profit + operating expenses, was expanded in terms of various cost parameters to enable analysis of multiregion nuclear reactors with uranium and/or plutonium for fuel. A corresponding IBM 704 computer program, which will compute either the price of electricity or the value of plutonium, is presented in detail. (auth)

Catalytic reactor for promoting a chemical reaction on a fluid passing therethrough

NASA Technical Reports Server (NTRS)

Roychoudhury, Subir (Inventor); Pfefferle, William C. (Inventor)

2001-01-01

A catalytic reactor with an auxiliary heating structure for raising the temperature of a fluid passing therethrough whereby the catalytic reaction is promoted. The invention is a apparatus employing multiple electrical heating elements electrically isolated from one another by insulators that are an integral part of the flow path. The invention provides step heating of a fluid as the fluid passes through the reactor.

Reactor design and integration into a nuclear electric spacecraft

NASA Technical Reports Server (NTRS)

Phillips, W. M.; Koenig, D. R.

1978-01-01

One of the well-defined applications for nuclear power in space is nuclear electric propulsion (NEP). Mission studies have identified the optimum power level (400 kWe). A single Shuttle launch requirement and science-package integration have added additional constraints to the design. A reactor design which will meet these constraints has been studied. The reactor employs 90 fuel elements, each heat pipe cooled. Reactor control is obtained with BeO/B4C drums in a BeO reflector. The balance of the spacecraft is shielded from the reactor with LiH. Power conditioning and reactor control drum drives are located behind the LiH with the power conditioning. Launch safety, mechanical design and integration with the power conversion subsystem are discussed.

Potential efficiencies of open- and closed-cycle CO, supersonic, electric-discharge lasers

NASA Technical Reports Server (NTRS)

Monson, D. J.

1976-01-01

Computed open- and closed-cycle system efficiencies (laser power output divided by electrical power input) are presented for a CW carbon monoxide, supersonic, electric-discharge laser. Closed-system results include the compressor power required to overcome stagnation pressure losses due to supersonic heat addition and a supersonic diffuser. The paper shows the effect on the system efficiencies of varying several important parameters. These parameters include: gas mixture, gas temperature, gas total temperature, gas density, total discharge energy loading, discharge efficiency, saturated gain coefficient, optical cavity size and location with respect to the discharge, and supersonic diffuser efficiency. Maximum open-cycle efficiency of 80-90% is predicted; the best closed-cycle result is 60-70%.

Electric cartridge-type heater for producing a given non-uniform axial power distribution

DOEpatents

Clark, D.L.; Kress, T.S.

1975-10-14

An electric cartridge heater is provided to simulate a reactor fuel element for use in safety and thermal-hydraulic tests of model nuclear reactor systems. The electric heat-generating element of the cartridge heater consists of a specifically shaped strip of metal cut with variable width from a flat sheet of the element material. When spirally wrapped around a mandrel, the strip produces a coiled element of the desired length and diameter. The coiled element is particularly characterized by an electrical resistance that varies along its length due to variations in strip width. Thus, the cartridge heater is constructed such that it will produce a more realistic simulation of the actual nonuniform (approximately ''chopped'' cosine) power distribution of a reactor fuel element.

Degradation of aqueous phenol solutions by coaxial DBD reactor

NASA Astrophysics Data System (ADS)

Dojcinovic, B. P.; Manojlovic, D.; Roglic, G. M.; Obradovic, B. M.; Kuraica, M. M.; Puric, J.

2008-07-01

Solutions of 2-chlorophenol, 4-chlorophenol and 2,6-dichlorophenol in bidistilled and water from the river Danube were treated in plasma reactor. In this reactor, based on coaxial dielectric barrier discharge at atmospheric pressure, plasma is formed over a thin layer of treated water. After one pass through the reactor, starting chlorophenols concentration of 20 mg/l was diminished up to 95 %. Kinetics of the chlorophenols degradation was monitored by High Pressure Liquid Chromatography method (HPLC).

[Experimental study of the effects of impulse-electric discharge on chemotaxis and cytoadhesion of urinary infection pathogens].

PubMed

Kuderinov, S K; Azizov, I S; Turgunov, E M; Shambilova, N A

2006-01-01

The aim of the experimental study was to evaluate effects of impulse-electric discharge in liquid on chemotaxis and cytoadhesion of urinary infection pathogens. Chemotaxis was determined in respect to the lung, liver, spleen, kidney, ureter, urinary bladder, urethra of white mice by S. Likholetov's modified method. Cytoadhesion was assessed by V. Brilis. The experiments show that the impulse-electric discharge holds promise for urological practice.

Synthesis of Silicon Nanoparticles in Inductively Coupled Plasmas

NASA Astrophysics Data System (ADS)

Markosyan, Aram H.; Le Picard, Romain; Girshick, Steven L.; Kushner, Mark J.

2016-09-01

The synthesis of silicon nanoparticles (Si-NPs) is being investigated for their use in photo-emitting electronics, photovoltaics, and biotechnology. The ability to control the size and mono-disperse nature of Si-NPs is important to optimizing these applications. In this paper we discuss results from a computational investigation of Si-NP formation and growth in an inductively coupled plasma (ICP) reactor with the goal of achieving this control. We use a two dimensional numerical model where the algorithms for the kinetics of NP formation are self-consistently coupled with a plasma hydrodynamics simulation. The reactor modeled here resembles a GEC reference cell through which, for the base case, a mixture of Ar/SiH4 = 70/30 flows at 150 sccm at a pressure of 100 mTorr. In continuous wave mode, three coils located on top of the reactor deliver 150 W. The electric plasma potential confines negatively charged particles at the center of the discharge, increasing the residence time of negative NPs, which enables the NPs to potentially grow to large and controllable sizes of many to 100s nm. We discuss methods of controlling NP growth rates by varying the mole fraction and flow rate of SiH4, and using a pulsed plasma by varying the pulse period and duty cycle. Work supported by DOE Office of Fusion Energy Science and National Science Foundation.

Paracetamol degradation in aqueous solution by non-thermal plasma

NASA Astrophysics Data System (ADS)

Baloul, Yasmine; Aubry, Olivier; Rabat, Hervé; Colas, Cyril; Maunit, Benoît; Hong, Dunpin

2017-08-01

This study deals with paracetamol degradation in water using a non-thermal plasma (NTP) created by a dielectric barrier discharge (DBD). The effects of the NTP operating conditions on the degradation were studied, showing that the treatment efficiency of the process was highly dependent on the electrical parameters and working gas composition in the reactor containing the aqueous solution. A conversion rate higher than 99% was reached with an energy yield of 12 g/kWh. High resolution mass spectrometry (HRMS) measurements showed that the main species produced in water during the process were nitrogen compounds, carboxylic acids and aromatic compounds. Contribution to the topical issue "The 15th International Symposium on High Pressure Low Temperature Plasma Chemistry (HAKONE XV)", edited by Nicolas Gherardi and Tomáš Hoder

Indirect-cycle FBR cooled by supercritical steam-concept and design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoshiaki, Oka; Tatjana, Jevremovic; Sei-ichi, Koshizuka

1993-01-01

Neutronic and thermal-hydraulic design of an in direct-cycle supercritical steam-cooled fast breeder reactor (SCFBR-I) is carried out to find a way to make low-cost FBRs (Ref. 1). The advantages of supercritical steam cooling are high thermal efficiency, low pumping power, simplified system (no primary steam generators and no Loeffler boilers), and the use of experienced technology in fossil-fired power plants. The design goals are fissile fuel breeding (compound system doubling time below 30 yr), 1000-M(electric) class out-put, high fuel discharge burnup, and a long refueling period. The coolant void reactivity should be negative throughout fuel lifetime because the loss-of-coolant accidentmore » is the design-basis accident. These goals have never been satisfied simultaneously in previous SCFBRs.« less

Wastewater infrastructure for small cities in an urbanizing world: integrating protection of human health and the environment with resource recovery and food security.

PubMed

Verbyla, Matthew E; Oakley, Stewart M; Mihelcic, James R

2013-04-16

The majority of population growth in developing countries will occur in small cities closely linked to agricultural zones, with poor access to water and sanitation. Wastewater management priorities in these regions will be different from those in larger cities and developed countries. Two wastewater treatment systems in Bolivia, one with an upflow anaerobic sludge blanket (UASB) reactor and polishing ponds, the other with three stabilization ponds, are assessed to determine their resource recovery potential. The UASB reactor produces biogas with 500-650 MJ per day. In six months, both systems discharge wastewater with the same mass of nutrients as fertilizers used to produce crops containing 10-75 days' worth of the recommended food energy intake for each person using the system. Both systems also discharge detectable levels of helminth eggs, Giardia cysts, and Cryptosporidium oocysts, but the UASB reactor system discharges higher concentrations, implying limited reuse potential. From a regional management standpoint, small cities should not expend resources to treat wastewater to levels suitable for discharge into surface waters. Rather, they should focus on removing pathogens to reclaim water and nutrients. Biogas recovery may be a priority that should be subservient to water and nutrient recovery in these settings.

Dependence of Initial Oxygen Concentration on Ozone Yield Using Inductive Energy Storage System Pulsed Power Generator

NASA Astrophysics Data System (ADS)

Go, Tomio; Tanaka, Yasushi; Yamazaki, Nobuyuki; Mukaigawa, Seiji; Takaki, Koichi; Fujiwara, Tamiya

Dependence of initial oxygen concentration on ozone yield using streamer discharge reactor driven by an inductive energy storage system pulsed power generator is described in this paper. Fast recovery type diodes were employed as semiconductor opening switch to interrupt a circuit current within 100 ns. This rapid current change produced high-voltage short pulse between a secondary energy storage inductor. The repetitive high-voltage short pulse was applied to a 1 mm diameter center wire electrode placed in a cylindrical pulse corona reactor. The streamer discharge successfully occurred between the center wire electrode and an outer cylinder ground electrode of 2 cm inner diameter. The ozone was produced with the streamer discharge and increased with increasing pulse repetition rate. The ozone yield changed in proportion to initial oxygen concentration contained in the injected gas mixture at 800 ns forward pumping time of the current. However, the decrease of the ozone yield by decreasing oxygen concentration in the gas mixture at 180 ns forward pumping time of the current was lower than the decrease at 800 ns forward pumping time of the current. This dependence of the initial oxygen concentration on ozone yield at 180 ns forward pumping time is similar to that of dielectric barrier discharge reactor.

Assessing the possible radiological impact of routine radiological discharges from proposed nuclear power stations in England and Wales.

PubMed

Jones, Alison; Jones, Kelly; Holmes, Sheila; Ewers, Leon; Cabianca, Tiberio

2013-03-01

The aim of this work is to assess the possible radiological impact on the population of the United Kingdom (UK) from new nuclear power stations proposed for up to eight sites in England and Wales. The radiological impact was measured in terms of collective dose to the UK, European and world populations from a single year's discharge integrated to 500 and 100 000 years and the annual dose to an average member of the UK population (known as the per-caput dose). The doses were calculated for two reactor types, UK EPR™ and AP1000™, using the annual expected discharges estimated by the designers of the reactors and assuming two reactors per site. In addition, typical individual doses to adults living close to the sites were calculated on the basis of continuous discharges for 60 years (the assumed lifetime of the reactors). The dose to a representative person (previously known as the critical group) was not calculated, as this has been done elsewhere. The assessments were carried out using the software program PC-CREAM 08(®) which implements the updated European Commission methodology for assessing the radiological impact of routine releases of radionuclides to the environment. The collective dose truncated to 500 years to the UK population was estimated to be 0.5 manSv assuming UK EPR reactors on all sites and 0.6 manSv assuming AP1000s on three sites with UK EPRs on the other sites. The most significant contribution to the collective dose to the UK population is due to the global circulation of carbon-14 released to the atmosphere. The annual dose to an average member of the UK population from all sites was calculated to be around 10 nSv y(-1) and would therefore contribute little to an individual's total radiation dose. All the calculated doses to a typical adult living near the sites assuming continuous discharges for 60 years were found to be below 1 μSv y(-1).

Electrical Breakdown Phenomena Involving Material Interfaces

DTIC Science & Technology

2013-06-01

create ozone through chemical reactions involving reactive species created by the electrical discharge [3]. The glow discharge breakdown in such...2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Investigation Of Pre-Ionization And Atmospheric Pulsed Discharge Plasma 5a...growth of the air discharge in the form of a conductive filament consisting of electrons and ions. This filament is created by temporal pulse that

Theoretical Investigations of Dielectric Breakdown in CO2: Implications for Atmospheric Discharges on Mars (and Venus)

NASA Astrophysics Data System (ADS)

Riousset, J. A.

2017-12-01

The detection of an atmospheric discharge in the Martian atmosphere by Ruf et al. [GRL, 36, L13202, 2009] supports the idea of a Martian atmospheric electric circuit [Farrell and Desch, JGR, 106, E4, 2001]. However, the lack of subsequent detection of similar events raises the question of the conditions of their initiation, and the existence of Martian lightning remains a controversial question. On Earth, atmospheric electricity manifests itself in the form of glow, corona, streamer, and leader discharges observed as Saint Elmo's fire, sprites, lightning and jets discharges, and other Transient Luminous Events (TLEs). All of these are dielectric breakdown governed by different physics. Their initiation is associated with the crossing of specific electric field thresholds: relativistic runaway, streamer propagation, conventional breakdown, or thermal runaway thresholds, some better understood than others. For example, the initiation of a lightning discharge is known to occur when the local electric field exceeds a value similar to relativistic runaway field, but the exact threshold, as well as the physical mechanisms at work, remain unclear to date. Scaling laws for electric fields (and other quantities) have been established by Pasko et al. [GRL, 25(12), 2123-2126, 1998] and Pasko [NATO Sci. Series, Springer, 253-311, 2006]. In this work, we develop profiles for initiation criteria in air and in other atmospheric environments. We further calculate their associated scaling laws to determine the ability to trigger lightning flashes and TLEs on Mars. This lets us predict the likelihood of electrical discharges and calculate the expected electric field conditions, under which discharges could be observed. We develop the analogy between Earth sand storm [Nicoll et al., Env. Res. Lett., 6, 014001, 2001] and Martian dust storms [Melnik and Parrot, JGR, 103(A12), 1998] to investigate the charge structure and resulting electric fields necessary to initiate dielectric breakdown in the Martian atmosphere. Initiation of electric discharges will be susceptible to local pressure, density, atmospheric composition, and charge structure, and will impact charge moment variations detectable by remote sensing.

Dynamic generation of supercritical water fluid in a strong electrical discharge in a liquid

NASA Astrophysics Data System (ADS)

Antonov, V.; Kalinin, N.; Kovalenko, A.

2016-11-01

A new impetus for the development of electro physics is associated with using different types of electrical discharges in biology and medicine. These applications are based on their energetic and non-toxic factors affecting the medium on a cellular level. For the study of such processes, a mathematical model of a high-current low-temperature Z-discharge in a liquid, forming by the electrical explosion of a thin-walled metal shell, connected to a pulsed high-voltage generator, has been developed. High efficiency energy conversion, introduced into the plasma discharge to the energy of fluid motion, provides various bio chemical applications of such physical processes. The investigation is conducted through numerical solution of one-dimensional single-temperature non-stationary equations of radiation magneto hydrodynamics, one way describing the evolution of hydrodynamic, thermal and electrical characteristics of the medium throughout the area under consideration. The electrical approximation based on the assumption that the electric field in the discharge has a uniform distribution. The results are presented as a function of the electric current and the plasma channel length of time, as well as the temperature and pressure distributions at different time points along the radius of the cylindrical region in which the explosion occurs.

A Pebble-Bed Breed-and-Burn Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greenspan, Ehud

2016-03-31

The primary objective of this project is to use three-dimensional fuel shuffling in order to reduce the minimum peak radiation damage of ~550 dpa present Breed-and-Burn (B&B) fast nuclear reactor cores designs (they feature 2-D fuel shuffling) call for to as close as possible to the presently accepted value of 200 dpa thereby enabling earlier commercialization of B&B reactors which could make substantial contribution to energy sustainability and economic stability without need for fuel recycling. Another objective is increasing the average discharge burnup for the same peak discharge burnup thereby (1) increasing the fuel utilization of 2-D shuffled B&B reactorsmore » and (2) reducing the reprocessing capacity required to support a given capacity of FRs that are to recycle fuel.« less

Flight Termination Systems Commonality Standard

DTIC Science & Technology

2014-09-01

input level is increased 60 dB from threshold. Corona : A visible electric discharge resulting from a partial electric breakdown of gases as the...4-49 Figure 4-10. Electrostatic Discharge Test...check channel telemetry output (EFTR) CDR critical design review CFS flight self- discharge in amp-hrs CR remaining capacity for determining

Experimental study of heating scheme effect on the inner divertor power footprint widths in EAST lower single null discharges

NASA Astrophysics Data System (ADS)

Deng, G. Z.; Xu, J. C.; Liu, X.; Liu, X. J.; Liu, J. B.; Zhang, H.; Liu, S. C.; Chen, L.; Yan, N.; Feng, W.; Liu, H.; Xia, T. Y.; Zhang, B.; Shao, L. M.; Ming, T. F.; Xu, G. S.; Guo, H. Y.; Xu, X. Q.; Gao, X.; Wang, L.

2018-04-01

A comprehensive work of the effects of plasma current and heating schemes on divertor power footprint widths is carried out in the experimental advanced superconducting tokamak (EAST). The divertor power footprint widths, i.e., the scrape-off layer heat flux decay length λ q and the heat spreading S, are crucial physical and engineering parameters for fusion reactors. Strong inverse scaling of λ q and S with plasma current have been demonstrated for both neutral beam (NB) and lower hybrid wave (LHW) heated L-mode and H-mode plasmas at the inner divertor target. For plasmas heated by the combination of the two kinds of auxiliary heating schemes (NB and LHW), the divertor power widths tend to be larger in plasmas with higher ratio of LHW power. Comparison between experimental heat flux profiles at outer mid-plane (OMP) and divertor target for NB heated and LHW heated L-mode plasmas reveals that the magnetic topology changes induced by LHW may be the main reason to the wider divertor power widths in LHW heated discharges. The effect of heating schemes on divertor peak heat flux has also been investigated, and it is found that LHW heated discharges tend to have a lower divertor peak heat flux compared with NB heated discharges under similar input power. All these findings seem to suggest that plasmas with LHW auxiliary heating scheme are better heat exhaust scenarios for fusion reactors and should be the priorities for the design of next-step fusion reactors like China Fusion Engineering Test Reactor.

Conversion of NO to NO(2) in air by a micro electric NO(x) converter based on a corona discharge process.

PubMed

Yoon, Seung-Il; Heo, Sungmoo; Song, Soonho; Kim, Yong-Jun

2010-06-01

A micro-electric-NO(x)-converter based on volume treatment is proposed for the evaluation of NO(x) concentrations in air. It can electrically convert NO(x) mixture from variable mixing rates into a fixed-mixing rate of 25% NO(2) and 75% NO using the corona discharge process with stable conversion efficiency and high throughput (space velocity = 6.3 x 10(4) h(-1)). The micro-electric-NO(x)-converter is based on a volume process. Applying high voltage to the electrodes of the micro-electric-NO(x)-converter generates a corona discharge. This discharge creates high-energy electrons, which collide with gas molecules. After these collisions, NO and O(2) are broken into single atoms, and they are re-combined as a balanced form, NO(2) in this case. The fabricated micro-electric-NO(x)-converter converted NO into NO(2) at conversion efficiency of 25.63%, when 5.5 kV (the applied corona power = 0.196 W) was applied to the micro-electric-NO(x)-converter.

Thermal storage/discharge performances of Cu-Si alloy for solar thermochemical process

NASA Astrophysics Data System (ADS)

Gokon, Nobuyuki; Yamaguchi, Tomoya; Cho, Hyun-seok; Bellan, Selvan; Hatamachi, Tsuyoshi; Kodama, Tatsuya

2017-06-01

The present authors (Niigata University, Japan) have developed a tubular reactor system using novel "double-walled" reactor/receiver tubes with carbonate molten-salt thermal storage as a phase change material (PCM) for solar reforming of natural gas and with Al-Si alloy thermal storage as a PCM for solar air receiver to produce high-temperature air. For both of the cases, the high heat capacity and large latent heat (heat of solidification) of the PCM phase circumvents the rapid temperature change of the reactor/receiver tubes at high temperatures under variable and uncontinuous characteristics of solar radiation. In this study, we examined cyclic properties of thermal storage/discharge for Cu-Si alloy in air stream in order to evaluate a potentiality of Cu-Si alloy as a PCM thermal storage material. Temperature-increasing performances of Cu-Si alloy are measured during thermal storage (or heat-charge) mode and during cooling (or heat-discharge) mode. A oxidation state of the Cu-Si alloy after the cyclic reaction was evaluated by using electron probe micro analyzer (EPMA).

Nuclear radiation problems, unmanned thermionic reactor ion propulsion spacecraft

NASA Technical Reports Server (NTRS)

Mondt, J. F.; Sawyer, C. D.; Nakashima, A.

1972-01-01

A nuclear thermionic reactor as the electric power source for an electric propulsion spacecraft introduces a nuclear radiation environment that affects the spacecraft configuration, the use and location of electrical insulators and the science experiments. The spacecraft is conceptually configured to minimize the nuclear shield weight by: (1) a large length to diameter spacecraft; (2) eliminating piping penetrations through the shield; and (3) using the mercury propellant as gamma shield. Since the alumina material is damaged by the high nuclear radiation environment in the reactor it is desirable to locate the alumina insulator outside the reflector or develop a more radiation resistant insulator.

Electric Discharge Sintering and Joining of Tungsten Carbide—Cobalt Composite with High-Speed Steel Substrate

NASA Astrophysics Data System (ADS)

Grigoryev, Evgeny G.

2011-01-01

Simultaneous electro discharge sintering of high strength structure of tungsten carbide—cobalt composite and connection it with high-speed steel substrate is investigated and suitable operating parameters are defined. Tungsten carbide—cobalt and high-speed steel joining was produced by the method of high voltage electrical discharge together with application of mechanical pressure to powder compact. It was found that the density and hardness of composite material reach its maximum values at certain magnitudes of applied pressure and high voltage electrical discharge parameters. We show that there is an upper level for the discharge voltage beyond which the powder of composite material disintegrates like an exploding wire. Due to our results it is possible to determine optimal parameters for simultaneous electro discharge sintering of WC-Co and bonding it with high-speed steel substrate.

Transuranic inventory reduction in repository by partitioning and transmutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, C.H.; Kazimi, M.S.

1992-01-01

The promise of a new reprocessing technology and the issuance of Environmental Protection Agency (EPA) and U.S. Nuclear Regulatory Commission regulations concerning a geologic repository rekindle the interest in partitioning and transmutation of transuranic (TRU) elements from discharged reactor fuel as a high level waste management option. This paper investigates the TRU repository inventory reduction capability of the proposed advanced liquid metal reactors (ALMRs) and integral fast reactors (IFRs) as well as the plutonium recycled light water reactors (LWRs).

Efficient 'Foton' electric-discharge KrCl laser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Panchenko, Aleksei N; Tarasenko, Viktor F

The design of the 'Foton' electric-discharge laser, optimised for operation on the basis of KrCl* molecules, and its energy parameters were investigated. At {lambda} = 222 nm the radiation energy was up to 250 mJ per pulse. The specific output radiation energy was 2.5 J litre{sup -1} and the laser efficiency was in excess of 0.8%. The possibility of further improvement of the characteristics of electric-discharge KrCl lasers are discussed. (lasers)

Discharging a DC bus capacitor of an electrical converter system

DOEpatents

Kajouke, Lateef A; Perisic, Milun; Ransom, Ray M

2014-10-14

A system and method of discharging a bus capacitor of a bidirectional matrix converter of a vehicle are presented here. The method begins by electrically shorting the AC interface of the converter after an AC energy source is disconnected from the AC interface. The method continues by arranging a plurality of switching elements of a second energy conversion module into a discharge configuration to establish an electrical current path from a first terminal of an isolation module, through an inductive element, and to a second terminal of the isolation module. The method also modulates a plurality of switching elements of a first energy conversion module, while maintaining the discharge configuration of the second energy conversion module, to at least partially discharge a DC bus capacitor.

Influence of High Speed Repetition of Pulsed Streamer Discharge Produced by Polarity-Reversed Traveling Wave on NO Oxidation

NASA Astrophysics Data System (ADS)

Matsuda, Eiji; Kadowaki, Kazunori; Nishimoto, Sakae; Kitani, Isamu

This paper describes experimental results of NO removal from a simulated exhausted gas using a barrier-type plasma reactor subjected to reciprocal traveling wave voltage pulses. A pulse-forming cable was charged and then grounded at one end without any resistance, so that a traveling wave reciprocated along the cable with a change in its polarity because the traveling wave was negatively reflected at the grounded-end. Transient discharge light between point-plane electrodes with a glass barrier was observed using a gated image-intensifier. Photographs of the transient discharge light indicated that many streamer channels extended widely in the gap at the initial stage in the voltage oscillation, while only an intense discharge channel was observed at the latter stage. NO removal tests were carried out using the reciprocal pulse generator and a coaxial plasma reactor with a cylindrical glass-barrier. Results indicated that the discharges at the first and the second polarity reversals contributed largely to the oxidation reaction from NO into NO2, whereas the contribution of the subsequent discharges in the latter stage to NO removal was small.

Nuclear power in the 21st century: Challenges and possibilities.

PubMed

Horvath, Akos; Rachlew, Elisabeth

2016-01-01

The current situation and possible future developments for nuclear power--including fission and fusion processes--is presented. The fission nuclear power continues to be an essential part of the low-carbon electricity generation in the world for decades to come. There are breakthrough possibilities in the development of new generation nuclear reactors where the life-time of the nuclear waste can be reduced to some hundreds of years instead of the present time-scales of hundred thousand of years. Research on the fourth generation reactors is needed for the realisation of this development. For the fast nuclear reactors, a substantial research and development effort is required in many fields--from material sciences to safety demonstration--to attain the envisaged goals. Fusion provides a long-term vision for an efficient energy production. The fusion option for a nuclear reactor for efficient production of electricity has been set out in a focussed European programme including the international project of ITER after which a fusion electricity DEMO reactor is envisaged.

78 FR 34431 - Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-07

...EPA is proposing a regulation that would strengthen the controls on discharges from certain steam electric power plants by revising technology-based effluent limitations guidelines and standards for the steam electric power generating point source category. Steam electric power plants alone contribute 50-60 percent of all toxic pollutants discharged to surface waters by all industrial categories currently regulated in the United States under the Clean Water Act. Furthermore, power plant discharges to surface waters are expected to increase as pollutants are increasingly captured by air pollution controls and transferred to wastewater discharges. This proposal, if implemented, would reduce the amount of toxic metals and other pollutants discharged to surface waters from power plants. EPA is considering several regulatory options in this rulemaking and has identified four preferred alternatives for regulation of discharges from existing sources. These four preferred alternatives differ with respect to the scope of requirements that would be applicable to existing discharges of pollutants found in two wastestreams generated at power plants. EPA estimates that the preferred options for this proposed rule would annually reduce pollutant discharges by 0.47 billion to 2.62 billion pounds, reduce water use by 50 billion to 103 billion gallons, cost $185 million to $954 million, and would be economically achievable.

High-irradiance reactor design with practical unfolded optics

NASA Astrophysics Data System (ADS)

Feuermann, Daniel; Gordon, Jeffrey M.

2008-08-01

In the design of high-temperature chemical reactors and furnaces, as well as high-radiance light projection applications, reconstituting the ultra-high radiance of short-arc discharge lamps at maximum radiative efficiency constitutes a significant challenge. The difficulty is exacerbated by the high numerical aperture necessary at both the source and the target. Separating the optic from both the light source and the target allows practical operation, control, monitoring, diagnostics and maintenance. We present near-field unfolded aplanatic optics as a feasible solution. The concept is illustrated with a design customized to a high-temperature chemical reactor for nano-material synthesis, driven by an ultra-bright xenon short-arc discharge lamp, with near-unity numerical aperture for both light input and light output. We report preliminary optical measurements for the first prototype, which constitutes a double-ellipsoid solution. We also propose compound unfolded aplanats that collect the full angular extent of lamp emission (in lieu of light recycling optics) and additionally permit nearly full-circumference irradiation of the reactor.

Conversion of nitrogen oxides in N2:O2:CO2 and N2:O2:CO2:NO2 mixtures subjected to a dc corona discharge

NASA Astrophysics Data System (ADS)

Dors, Mirosław; Mizeraczyk, Jerzy

1996-10-01

This paper concerns the influence of a direct current (dc) corona discharge on production and reduction of NO, NO2 and N2O in N2:O2:CO2 and N2:O2:CO2:NO2 mixtures. The corona discharge was generated in a needle-to-plate reactor. The positively polarized electrode consisted of 7 needles. The grounded electrode was a stainless steel plate. The gas flow rate through the reactor was varied from 28 to 110 cm3/s. The time-averaged discharge current ranged from 0 to 6 mA. It was found that in the N2:O2:CO2 mixture the corona discharge produced NO, NO2 and N2O. In the N2:O2:CO2:NO2 mixture the reduction of NO2 was between 6-56%, depending on the concentration of O2, gas flow rate and corona discharge current. The NO2 reduction was accompanied by production of NO and N2O. The results show that efficient reduction of nitrogen oxides by a corona discharge cannot be expected in the mixtures containing N2 and O2 if reducing additives are not employed.

Effect of packing material on methane activation in a dielectric barrier discharge reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jo, Sungkwon; Hoon Lee, Dae; Seok Kang, Woo

2013-12-15

The conversion of methane is measured in a planar-type dielectric barrier discharge reactor using γ-Al{sub 2}O{sub 3} (sphere), α-Al{sub 2}O{sub 3} (sphere), and γ-Al{sub 2}O{sub 3} (16–20 mesh). Investigations on the surface properties and shape of the three packing materials clearly indicate that methane activation is considerably affected by the material used. Capacitances inside the discharge gap are estimated from charge–voltage plots, and a comparison of the generated and transferred charges for different packing conditions show that the difference in surface properties between γ- and α-phase Al{sub 2}O{sub 3} affects the discharge characteristics. Moreover, all packing conditions show different chargemore » characteristics that are related to the electron density. Finally, the packing material's shape affects the local electron temperature, which is strongly related to methane conversion. The combined results indicate that both microscale and macroscale variations in a packing material affect the discharge characteristics, and a packing material should be considered carefully for effective methane activation.« less

Apollo - An advanced fuel fusion power reactor for the 21st century

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kulcinski, G.L.; Emmert, G.A.; Blanchard, J.P.

1989-03-01

A preconceptual design of a tokamak reactor fueled by a D-He-3 plasma is presented. A low aspect ratio (A=2-4) device is studied here but high aspect ratio devices (A > 6) may also be quite attractive. The Apollo D-He-3 tokamak capitalizes on recent advances in high field magnets (20 T) and utilizes rectennas to convert the synchrotron radiation directly to electricity. The overall efficiency ranges from 37 to 52% depending on whether the bremsstrahlung energy is utilized. The low neutron wall loading (0.1 MW/m/sup 2/) allows a permanent first wall to be designed and the low nuclear decay heat enablesmore » the reactor to be classed as inherently safe. The cost of electricity from Apollo is > 40% lower than electricity from a similar sized DT reactor.« less

Evaluation of Fatigue Behavior and Surface Characteristics of Aluminum Alloy 2024 T6 After Electric Discharge Machining

NASA Astrophysics Data System (ADS)

Mehmood, Shahid; Shah, Masood; Pasha, Riffat Asim; Sultan, Amir

2017-10-01

The effect of electric discharge machining (EDM) on surface quality and consequently on the fatigue performance of Al 2024 T6 is investigated. Five levels of discharge current are analyzed, while all other electrical and nonelectrical parameters are kept constant. At each discharge current level, dog-bone specimens are machined by generating a peripheral notch at the center. The fatigue tests are performed on four-point rotating bending machine at room temperature. For comparison purposes, fatigue tests are also performed on the conventionally machined specimens. Linearized SN curves for 95% failure probability and with four different confidence levels (75, 90, 95 and 99%) are plotted for each discharge current level as well as for conventionally machined specimens. These plots show that the electric discharge machined (EDMed) specimens give inferior fatigue behavior as compared to conventionally machined specimen. Moreover, discharge current inversely affects the fatigue life, and this influence is highly pronounced at lower stresses. The EDMed surfaces are characterized by surface properties that could be responsible for change in fatigue life such as surface morphology, surface roughness, white layer thickness, microhardness and residual stresses. It is found that all these surface properties are affected by changing discharge current level. However, change in fatigue life by discharge current could not be associated independently to any single surface property.

Laser-guided energetic discharges over large air gaps by electric-field enhanced plasma filaments

NASA Astrophysics Data System (ADS)

Théberge, Francis; Daigle, Jean-François; Kieffer, Jean-Claude; Vidal, François; Châteauneuf, Marc

2017-01-01

Recent works on plasma channels produced during the propagation of ultrashort and intense laser pulses in air demonstrated the guiding of electric discharges along the laser path. However, the short plasma lifetime limits the length of the laser-guided discharge. In this paper, the conductivity and lifetime of long plasma channels produced by ultrashort laser pulses is enhanced efficiently over many orders of magnitude by the electric field of a hybrid AC-DC high-voltage source. The AC electric pulse from a Tesla coil allowed to stimulate and maintain the highly conductive channel during few milliseconds in order to guide a subsequent 500 times more energetic discharge from a 30-kV DC source. This DC discharge was laser-guided over an air gap length of two metres, which is more than two orders of magnitude longer than the expected natural discharge length. Long plasma channel induced by laser pulses and stimulated by an external high-voltage source opens the way for wireless and efficient transportation of energetic current pulses over long air gaps and potentially for guiding lightning.

Laser-guided energetic discharges over large air gaps by electric-field enhanced plasma filaments

PubMed Central

Théberge, Francis; Daigle, Jean-François; Kieffer, Jean-Claude; Vidal, François; Châteauneuf , Marc

2017-01-01

Recent works on plasma channels produced during the propagation of ultrashort and intense laser pulses in air demonstrated the guiding of electric discharges along the laser path. However, the short plasma lifetime limits the length of the laser-guided discharge. In this paper, the conductivity and lifetime of long plasma channels produced by ultrashort laser pulses is enhanced efficiently over many orders of magnitude by the electric field of a hybrid AC-DC high-voltage source. The AC electric pulse from a Tesla coil allowed to stimulate and maintain the highly conductive channel during few milliseconds in order to guide a subsequent 500 times more energetic discharge from a 30-kV DC source. This DC discharge was laser-guided over an air gap length of two metres, which is more than two orders of magnitude longer than the expected natural discharge length. Long plasma channel induced by laser pulses and stimulated by an external high-voltage source opens the way for wireless and efficient transportation of energetic current pulses over long air gaps and potentially for guiding lightning. PMID:28053312

Measured electric field intensities near electric cloud discharges detected by the Kennedy Space Center's Lightning Detection and Ranging System, LDAR

NASA Technical Reports Server (NTRS)

Poehler, H. A.

1977-01-01

For a summer thunderstorm, for which simultaneous, airborne electric field measurements and Lightning Detection and Ranging (LDAR) System data was available, measurements were coordinated to present a picture of the electric field intensity near cloud electrical discharges detected by the LDAR System. Radar precipitation echos from NOAA's 10 cm weather radar and measured airborne electric field intensities were superimposed on LDAR PPI plots to present a coordinated data picture of thunderstorm activity.

ETR ELECTRICAL BUILDING, TRA648. EMERGENCY STANDBY GENERATOR AND DIESEL UNIT. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR ELECTRICAL BUILDING, TRA-648. EMERGENCY STANDBY GENERATOR AND DIESEL UNIT. METAL ROOF AND PUMICE BLOCK WALLS. CAMERA FACING SOUTHWEST. INL NEGATIVE NO. 56-3708. R.G. Larsen, Photographer, 11/13/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

ETR ELECTRICAL BUILDING, TRA648. FLOOR PLANS FOR FIRST FLOOR AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR ELECTRICAL BUILDING, TRA-648. FLOOR PLANS FOR FIRST FLOOR AND BASEMENT. SECTIONS. KAISER ETR-5528-MTR-648-A-2, 12/1955. INL INDEX NO. 532-0648-00-486-101402, REV. 6. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

ETR ELECTRICAL BUILDING, TRA648. ELEVATIONS AND DETAILS. ROOF PLAN. DOOR ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR ELECTRICAL BUILDING, TRA-648. ELEVATIONS AND DETAILS. ROOF PLAN. DOOR SCHEDULE. KAISER ETR-5528-MTR-648-A-3, 1/1956. INL INDEX NO. 532-0648-00-486-101403, REV. 5. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

75 FR 61227 - Advisory Committee on Reactor Safeguards Meeting of the ACRS Subcommittee on Future Plant Designs...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-04

... Westinghouse Electric Company, General Electric--Hitachi Nuclear Energy (GEH), and their contractors, pursuant... NUCLEAR REGULATORY COMMISSION Advisory Committee on Reactor Safeguards Meeting of the ACRS Subcommittee on Future Plant Designs; Revision to the September 24, 2010, ACRS Meeting Federal Register Notice...

Fast 2D fluid-analytical simulation of ion energy distributions and electromagnetic effects in multi-frequency capacitive discharges

NASA Astrophysics Data System (ADS)

Kawamura, E.; Lieberman, M. A.; Graves, D. B.

2014-12-01

A fast 2D axisymmetric fluid-analytical plasma reactor model using the finite elements simulation tool COMSOL is interfaced with a 1D particle-in-cell (PIC) code to study ion energy distributions (IEDs) in multi-frequency capacitive argon discharges. A bulk fluid plasma model, which solves the time-dependent plasma fluid equations for the ion continuity and electron energy balance, is coupled with an analytical sheath model, which solves for the sheath parameters. The time-independent Helmholtz equation is used to solve for the fields and a gas flow model solves for the steady-state pressure, temperature and velocity of the neutrals. The results of the fluid-analytical model are used as inputs to a PIC simulation of the sheath region of the discharge to obtain the IEDs at the target electrode. Each 2D fluid-analytical-PIC simulation on a moderate 2.2 GHz CPU workstation with 8 GB of memory took about 15-20 min. The multi-frequency 2D fluid-analytical model was compared to 1D PIC simulations of a symmetric parallel-plate discharge, showing good agreement. We also conducted fluid-analytical simulations of a multi-frequency argon capacitively coupled plasma (CCP) with a typical asymmetric reactor geometry at 2/60/162 MHz. The low frequency 2 MHz power controlled the sheath width and sheath voltage while the high frequencies controlled the plasma production. A standing wave was observable at the highest frequency of 162 MHz. We noticed that adding 2 MHz power to a 60 MHz discharge or 162 MHz to a dual frequency 2 MHz/60 MHz discharge can enhance the plasma uniformity. We found that multiple frequencies were not only useful for controlling IEDs but also plasma uniformity in CCP reactors.

The effects of electric power industry restructuring on the safety of nuclear power plants in the United States

NASA Astrophysics Data System (ADS)

Butler, Thomas S.

Throughout the United States the electric utility industry is restructuring in response to federal legislation mandating deregulation. The electric utility industry has embarked upon an extraordinary experiment by restructuring in response to deregulation that has been advocated on the premise of improving economic efficiency by encouraging competition in as many sectors of the industry as possible. However, unlike the telephone, trucking, and airline industries, the potential effects of electric deregulation reach far beyond simple energy economics. This dissertation presents the potential safety risks involved with the deregulation of the electric power industry in the United States and abroad. The pressures of a competitive environment on utilities with nuclear power plants in their portfolio to lower operation and maintenance costs could squeeze them to resort to some risky cost-cutting measures. These include deferring maintenance, reducing training, downsizing staff, excessive reductions in refueling down time, and increasing the use of on-line maintenance. The results of this study indicate statistically significant differences at the .01 level between the safety of pressurized water reactor nuclear power plants and boiling water reactor nuclear power plants. Boiling water reactors exhibited significantly more problems than did pressurized water reactors.

Changing the surface properties on naval steel as result of non-thermal plasma treatment

NASA Astrophysics Data System (ADS)

Hnatiuc, B.; Sabău, A.; Dumitrache, C. L.; Hnatiuc, M.; Crețu, M.; Astanei, D.

2016-08-01

The problem of corrosion, related to Biofouling formation, is an issue with very high importance in the maritime domain. According to new rules, the paints and all the technologies for the conditioning of naval materials must fulfil more restrictive environmental conditions. In order to solve this issue, different new clean technologies have been proposed. Among them, the use of non-thermal plasmas produced at atmospheric pressure plays a very important role. This study concerns the opportunity of plasma treatment for preparation or conditioning of naval steel OL36 type. The plasma reactors chosen for the experiments can operate at atmospheric pressure and are easy to use in industrial conditions. They are based on electrical discharges GlidArc and Spark, which already proved their efficiency for the surface activation or even for coatings of the surface. The non-thermal character of the plasma is ensured by a gas flow blown through the electrical discharges. One power supply has been used for reactors that provide a 5 kV voltage and a maximum current of 100 mA. The modifications of the surface properties and composition have been studied by XPS technique (X-ray Photoelectron Spectroscopy). There were taken into consideration 5 samples: 4 of them undergoing a Mini-torch plasma, a Gliding Spark, a GlidArc with dry air and a GlidArc with CO2, respectively the fifth sample which is the untreated witness. Before the plasma treatment, samples of naval steel were processed in order to obtain mechanical gloss. The time of treatment was chosen to 12 minutes. In the spectroscopic analysis, done on a ULVAC-PHI, Inc. PHI 5000 Versa Probe scanning XPS microprobe, a monocromated Al Kα X-ray source with a spot size of 100 μm2 was used to scan each sample while the photoelectrons were collected at a 45-degree take-off angle. Differences were found between atomic concentrations in each individual case, which proves that the active species produced by each type of plasma affects the surface properties of the treated naval steel.

Lightning Mapping Observations of Volume-Filling Small Discharges in Thunderstorms

NASA Astrophysics Data System (ADS)

Rison, W.; Krehbiel, P. R.; Thomas, R. J.; Rodeheffer, D.

2013-12-01

Lightning is usually considered to be a large-scale electrical discharge in the atmosphere. For example, the American Meteorological Society's Glossary of Meteorology defines lightning as "a transient, high-current electric discharge with pathlengths measured in kilometers" (http://glossary.ametsoc.org/wiki/Lightning). There have been several reported examples of short-duration discharges in thunderstorms, which have a duration of a few microseconds to less than a millisecond, and have a small spatial extent These short-duration discharges were located at high altitudes (> 14 km), altitudes consistent with being located between the upper positive charge and the negative screening layer. At these altitudes, the electric field needed to initiate an electrical discharge is much lower than it is at the altitudes of initiation for IC (~8 km) or CG (~5 km) flashes. We have recently reported on short-duration "precursor" discharges with durations of a few microseconds to a few milliseconds, which occur in the high-fields between the mid-level negative and upper positive charge regions. These "precursor" discharges are discrete in both time and space, being separated in time by hundreds of milliseconds to several seconds, and localized in space, usually very close to the initiation location of a subsequent IC discharge. We have recently observed nearly continuous, volume filling short-duration discharges in several thunderstorms. These discharges have durations of much less than a millisecond, spatial extents of less than a few hundred meters, and occur randomly in the volume between the mid-level negative and upper positive charge regions. During an active period, these discharges occur every few milliseconds. The rates of these discharges decreases dramatically to a few per second following an IC discharge, then increases to several hundred per second until the next discharge. In a storm just off the Florida coast, one cell was producing a large number of these small discharges, while a contemporaneous cell a few kilometers west produced no detectable small discharges. Short-duration discharges occur at altitudes between 10 km and 14 km in the intervals between lightning discharges. The rates of short-duration discharges decreases dramatically after a lightning discharge.

Nuclear reactor melt-retention structure to mitigate direct containment heating

DOEpatents

Tutu, Narinder K.; Ginsberg, Theodore; Klages, John R.

1991-01-01

A light water nuclear reactor melt-retention structure to mitigate the extent of direct containment heating of the reactor containment building. The structure includes a retention chamber for retaining molten core material away from the upper regions of the reactor containment building when a severe accident causes the bottom of the pressure vessel of the reactor to fail and discharge such molten material under high pressure through the reactor cavity into the retention chamber. In combination with the melt-retention chamber there is provided a passageway that includes molten core droplet deflector vanes and has gas vent means in its upper surface, which means are operable to deflect molten core droplets into the retention chamber while allowing high pressure steam and gases to be vented into the upper regions of the containment building. A plurality of platforms are mounted within the passageway and the melt-retention structure to direct the flow of molten core material and help retain it within the melt-retention chamber. In addition, ribs are mounted at spaced positions on the floor of the melt-retention chamber, and grid means are positioned at the entrance side of the retention chamber. The grid means develop gas back pressure that helps separate the molten core droplets from discharged high pressure steam and gases, thereby forcing the steam and gases to vent into the upper regions of the reactor containment building.

Minimizing radiation damage in nonlinear optical crystals

DOEpatents

Cooke, D.W.; Bennett, B.L.; Cockroft, N.J.

1998-09-08

Methods are disclosed for minimizing laser induced damage to nonlinear crystals, such as KTP crystals, involving various means for electrically grounding the crystals in order to diffuse electrical discharges within the crystals caused by the incident laser beam. In certain embodiments, electrically conductive material is deposited onto or into surfaces of the nonlinear crystals and the electrically conductive surfaces are connected to an electrical ground. To minimize electrical discharges on crystal surfaces that are not covered by the grounded electrically conductive material, a vacuum may be created around the nonlinear crystal. 5 figs.

Discharge processes and an electrical model of atmospheric pressure plasma jets in argon

NASA Astrophysics Data System (ADS)

Fang, Zhi; Shao, Tao; Yang, Jing; Zhang, Cheng

2016-01-01

In this paper, an atmospheric pressure plasma discharge in argon was generated using a needle-to-ring electrode configuration driven by a sinusoidal excitation voltage. The electric discharge processes and discharge characteristics were investigated by inspecting the voltage-current waveforms, Lissajous curves and lighting emission images. The change in discharge mode with applied voltage amplitude was studied and characterised, and three modes of corona discharge, dielectric barrier discharge (DBD) and jet discharge were identified, which appeared in turn with increasing applied voltage and can be distinguished clearly from the measured voltage-current waveforms, light-emission images and the changing gradient of discharge power with applied voltage. Based on the experimental results and discharge mechanism analysis, an equivalent electrical model and the corresponding equivalent circuit for characterising the whole discharge processes accurately was proposed, and the three discharge stages were characterised separately. A voltage-controlled current source (VCCS) associated with a resistance and a capacitance were used to represent the DBD stage, and the plasma plume and corona discharge were modelled by a variable capacitor in series with a variable resistor. Other factors that can influence the discharge, such as lead and stray capacitance values of the circuit, were also considered in the proposed model. Contribution to the Topical Issue "Recent Breakthroughs in Microplasma Science and Technology", edited by Kurt Becker, Jose Lopez, David Staack, Klaus-Dieter Weltmann and Wei Dong Zhu.

Electric-discharge-pumped nitrogen ion laser

NASA Technical Reports Server (NTRS)

Laudenslager, J. B.; Pacala, T. J.; Wittig, C.

1976-01-01

The routine operation is described of an N2(+) laser oscillating on the first negative band system of N2(+) which is produced in a preionized transverse discharge device. The discharge design incorporates features which favor the efficient production of the excitation transfer reaction of He2(+) with N2. A capacitive discharge switched by means of a high-current grounded grid thyratron is used to meet the design requirement of a volumetric discharge in high-pressure gas mixtures where the electric discharge need not have an ultrafast rise time (greater than 10 nsec) but should be capable of transferring large quantities of stored electric energy to the gas. A peak power of 180 kW in an 8-nsec laser pulse was obtained with a 0.1% mixture of N2 in helium at a total pressure of 3 atm. The most intense laser oscillations were observed on the (0,1) vibrational transition at 427.8 microns.

Electric field measurement in microwave discharge ion thruster with electro-optic probe.

PubMed

Ise, Toshiyuki; Tsukizaki, Ryudo; Togo, Hiroyoshi; Koizumi, Hiroyuki; Kuninaka, Hitoshi

2012-12-01

In order to understand the internal phenomena in a microwave discharge ion thruster, it is important to measure the distribution of the microwave electric field inside the discharge chamber, which is directly related to the plasma production. In this study, we proposed a novel method of measuring a microwave electric field with an electro-optic (EO) probe based on the Pockels effect. The probe, including a cooling system, contains no metal and can be accessed in the discharge chamber with less disruption to the microwave distribution. This method enables measurement of the electric field profile under ion beam acceleration. We first verified the measurement with the EO probe by a comparison with a finite-difference time domain numerical simulation of the microwave electric field in atmosphere. Second, we showed that the deviations of the reflected microwave power and the beam current were less than 8% due to inserting the EO probe into the ion thruster under ion beam acceleration. Finally, we successfully demonstrated the measurement of the electric-field profile in the ion thruster under ion beam acceleration. These measurements show that the electric field distribution in the thruster dramatically changes in the ion thruster under ion beam acceleration as the propellant mass flow rate increases. These results indicate that this new method using an EO probe can provide a useful guide for improving the propulsion of microwave discharge ion thrusters.

5 CFR 5801.102 - Prohibited securities.

Code of Federal Regulations, 2014 CFR

2014-01-01

... licenses for facilities which generate electric energy by means of a nuclear reactor; (2) State or local... reactor or a low-level waste facility; (3) Entities manufacturing or selling nuclear power or test reactors; (4) Architectural-engineering companies providing services relating to a nuclear power reactor...

5 CFR 5801.102 - Prohibited securities.

Code of Federal Regulations, 2010 CFR

2010-01-01

... licenses for facilities which generate electric energy by means of a nuclear reactor; (2) State or local... reactor or a low-level waste facility; (3) Entities manufacturing or selling nuclear power or test reactors; (4) Architectural-engineering companies providing services relating to a nuclear power reactor...

Electric Organ Discharges of Mormyrid Fish as a Possible Cue for Predatory Catfish

NASA Astrophysics Data System (ADS)

Hanika, S.; Kramer, B.

During reproductive migration the electroreceptive African sharptooth catfish, Clarias gariepinus (Siluriformes), preys mainly on a weakly electric fish, the bulldog Marcusenius macrolepidotus (Mormyridae; Merron 1993). This is puzzling because the electric organ discharges of known Marcusenius species are pulses of a duration (<1ms) too short for being detected by the catfishes' low-frequency electroreceptive system (optimum sensitivity, 10-30Hz Peters and Bretschneider 1981). On the recent discovery that M. macrolepidotus males emit discharges lasting approximately ten times longer than those of females (Kramer 1997a) we determined behavioral thresholds for discharges of both sexes, using synthetic playbacks of field-recorded discharges. C. gariepinus detected M. macrolepidotus male discharges down to a field gradient of 103μVpeak-peak/cm and up to a distance of 1.5m at natural field conditions. In contrast, thresholds for female discharges were not reached with our setup, and we presume the bulldogs eaten by catfish are predominantly male.

Pressure letdown method and device for coal conversion systems

NASA Technical Reports Server (NTRS)

Kendal, J. M.; Walsh, J. V. (Inventor)

1983-01-01

In combination with a reactor for a coal utilization system, a pressure letdown device accepts from a reactor, a polyphase fluid at an entrance pressure and an entrance velocity, and discharges the fluid from the device at a discharge pressure substantially lower than the entrance pressure and at a discharge temperature and a discharge velocity substantially equal to the entrance temperature and entrance velocity. The device is characterized by a series of pressure letdown stages including several symmetrical baffles, disposed in coaxially nested alignment. In each baffle several ports or apertures of uniform dimensions are defined. The number of ports or apertures for each baffle plate is unique with respect to the number of ports or apertures defined in each of the other baffles. The mass rate of flow for each port is a function of the area of the port, the pressure of the fluid as applied to the port, and a common pressure ratio established across the ports.

Experimental observation of the inductive electric field and related plasma nonuniformity in high frequency capacitive discharge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahn, S. K.; Chang, H. Y.

To elucidate plasma nonuniformity in high frequency capacitive discharges, Langmuir probe and B-dot probe measurements were carried out in the radial direction in a cylindrical capacitive discharge driven at 90 MHz with argon pressures of 50 and 400 mTorr. Through the measurements, a significant inductive electric field (i.e., time-varying magnetic field) was observed at the radial edge, and it was found that the inductive electric field creates strong plasma nonuniformity at high pressure operation. The plasma nonuniformity at high pressure operation is physically similar to the E-H mode transition typically observed in inductive discharges. This result agrees well with themore » theories of electromagnetic effects in large area and/or high frequency capacitive discharges.« less

Electric discharge during electrosurgery

PubMed Central

Shashurin, Alexey; Scott, David; Zhuang, Taisen; Canady, Jerome; Beilis, Isak I.; Keidar, Michael

2015-01-01

Electric discharge utilized for electrosurgery is studied by means of a recently developed method for the diagnostics of small-size atmospheric plasma objects based on Rayleigh scattering of microwaves on the plasma volume. Evolution of the plasma parameters in the near-electrode sheaths and in the positive column is measured and analyzed. It is found that the electrosurgical system produces a glow discharge of alternating current with strongly contracted positive column with current densities reaching 103 A/cm2. The plasma electron density and electrical conductivities in the channel were found be 1016 cm−3 and (1-2) Ohm−1cm−1, respectively. The discharge interrupts every instance when the discharge-driving AC voltage crosses zero and re-ignites again every next half-wave at the moment when the instant voltage exceeds the breakdown threshold. PMID:25880721

Television image of a large upward electrical discharge above a thunderstorm system

NASA Technical Reports Server (NTRS)

Franz, R. C.; Nemzek, R. J.; Winckler, J. R.

1990-01-01

A low light-level TV camera is used to obtain an unusual image of luminous electrical discharge over a thunderstorm 250 km from the observation site. The image is presented and the discharge in the image is described. It is suggested that the image is probably due to two localized electric charge concentrations at the cloud tops. The hazard of these discharges for aircraft and rocket launches is examined. Consideration is given to the possibility that these discharges may account for unexplained photometric observations of distant lightning events that show a low rise rate of the luminous pulse and no electromagnetic sferic pulse like that in cloud-to-earth lightning strokes. The photometric events of this type that occurred on September 22-23, 1989 during hurricane Hugo are noted.

Electric discharge during electrosurgery.

PubMed

Shashurin, Alexey; Scott, David; Zhuang, Taisen; Canady, Jerome; Beilis, Isak I; Keidar, Michael

2015-04-16

Electric discharge utilized for electrosurgery is studied by means of a recently developed method for the diagnostics of small-size atmospheric plasma objects based on Rayleigh scattering of microwaves on the plasma volume. Evolution of the plasma parameters in the near-electrode sheaths and in the positive column is measured and analyzed. It is found that the electrosurgical system produces a glow discharge of alternating current with strongly contracted positive column with current densities reaching 10(3) A/cm(2). The plasma electron density and electrical conductivities in the channel were found be 10(16) cm(-3) and (1-2) Ohm(-1) cm(-1), respectively. The discharge interrupts every instance when the discharge-driving AC voltage crosses zero and re-ignites again every next half-wave at the moment when the instant voltage exceeds the breakdown threshold.

Mechanism of the free charge carrier generation in the dielectric breakdown

NASA Astrophysics Data System (ADS)

Rahim, N. A. A.; Ranom, R.; Zainuddin, H.

2017-12-01

Many studies have been conducted to investigate the effect of environmental, mechanical and electrical stresses on insulator. However, studies on physical process of discharge phenomenon, leading to the breakdown of the insulator surface are lacking and difficult to comprehend. Therefore, this paper analysed charge carrier generation mechanism that can cause free charge carrier generation, leading toward surface discharge development. Besides, this paper developed a model of surface discharge based on the charge generation mechanism on the outdoor insulator. Nernst’s Planck theory was used in order to model the behaviour of the charge carriers while Poisson’s equation was used to determine the distribution of electric field on insulator surface. In the modelling of surface discharge on the outdoor insulator, electric field dependent molecular ionization was used as the charge generation mechanism. A mathematical model of the surface discharge was solved using method of line technique (MOL). The result from the mathematical model showed that the behaviour of net space charge density was correlated with the electric field distribution.

Television Image of a Large Upward Electrical Discharge Above a Thunderstorm System

NASA Astrophysics Data System (ADS)

Franz, R. C.; Nemzek, R. J.; Winckler, J. R.

1990-07-01

An image of an unusual luminous electrical discharge over a thunderstorm 250 kilometers from the observing site has been obtained with a low-light-level television camera. The discharge began at the cloud tops at 14 kilometers and extended into the clear air 20 kilometers higher. The image, which had a duration of less than 30 milliseconds, resembled two jets or fountains and was probably caused by two localized electric charge concentrations at the cloud tops. Large upward discharges may create a hazard for aircraft and rocket launches and, by penetrating into the ionosphere, may initiate whistler waves and other effects on a magnetospheric scale. Such upward electrical discharges may account for unexplained photometric observations of distant lightning events that showed a low rise rate of the luminous pulse and no electromagnetic sferic pulse of the type that accompanies cloud-to-earth lightning strokes. An unusually high rate of such photometric events was recorded during the night of 22 to 23 September 1989 during a storm associated with hurricane Hugo.

Television image of a large upward electrical discharge above a thunderstorm system.

PubMed

Franz, R C; Nemzek, R J; Winckler, J R

1990-07-06

An image of an unusual luminous electrical discharge over a thunderstorm 250 kilometers from the observing site has been obtained with a low-light-level television camera. The discharge began at the cloud tops at 14 kilometers and extended into the clear air 20 kilometers higher. The image, which had a duration of less than 30 milliseconds,resembled two jets or fountains and was probably caused by two localizd electric charge concentrations at the cloud tops. Large upward discharges may create a hazard for aircraft and rocket launches and, by penetrating into the ionosphere, may initiate whistler waves and other effects on a magnetospheric scale. Such upward electrical discharges may account for unexplained photometric observations of distant lightning events that showed a low rise rate of the luminous pulse and no electromagnetic sferic pulse of the type that accompanies cloud-to-earth lightning strokes. An unusually high rate of such photometric events was recorded during the night of 22 to 23 September 1989 during a storm associated with hurricane Hugo.

Timing Actions to Avoid Refractoriness: A Simple Solution for Streaming Sensory Signals

PubMed Central

Nogueira, Javier; Caputi, Ángel Ariel

2011-01-01

Segmenting self- from allo-generated signals is crucial for active sensory processing. We report a dynamic filter used by South American pulse electric fish to distinguish active electro-sensory signals carried by their own electric discharges from other concomitant electrical stimuli (i.e. communication signals). The filter has a sensory component, consisting of an onset type central electro-sensory neuron, and a motor component, consisting of a change in the fish's discharge rate when allo-generated electrical events occur in temporal proximity to the fish's own discharge. We investigated the sensory component of the filter by in vitro mimicking synaptic inputs occurring during behavioral responses to allo-generated interfering signals. We found that active control of the discharge enhances self-generated over allo-generated responses by forcing allo-generated signals into a central refractory period. This hypothesis was confirmed by field potential recordings in freely discharging fish. Similar sensory-motor mechanisms may also contribute to signal segmentation in other sensory systems. PMID:21789228

Water purification by electrical discharges

NASA Astrophysics Data System (ADS)

Arif Malik, Muhammad; Ghaffar, Abdul; Akbar Malik, Salman

2001-02-01

There is a continuing need for the development of effective, cheap and environmentally friendly processes for the disinfection and degradation of organic pollutants from water. Ozonation processes are now replacing conventional chlorination processes because ozone is a stronger oxidizing agent and a more effective disinfectant without any side effects. However, the fact that the cost of ozonation processes is higher than chlorination processes is their main disadvantage. In this paper recent developments targeted to make ozonation processes cheaper by improving the efficiency of ozone generation, for example, by incorporation of catalytic packing in the ozone generator, better dispersion of ozone in water and faster conversion of dissolved ozone to free radicals are described. The synthesis of ozone in electrical discharges is discussed. Furthermore, the generation and plasma chemical reactions of several chemically active species, such as H2O2, Obullet, OHbullet, HO2bullet, O3*, N2*, e-, O2-, O-, O2+, etc, which are produced in the electrical discharges are described. Most of these species are stronger oxidizers than ozone. Therefore, water treatment by direct electrical discharges may provide a means to utilize these species in addition to ozone. Much research and development activity has been devoted to achieve these targets in the recent past. An overview of these techniques and important developments that have taken place in this area are discussed. In particular, pulsed corona discharge, dielectric barrier discharge and contact glow discharge electrolysis techniques are being studied for the purpose of cleaning water. The units based on electrical discharges in water or close to the water level are being tested at industrial-scale water treatment plants.}

Response of lead-acid batteries to chopper-controlled discharge: Preliminary results

NASA Technical Reports Server (NTRS)

Cataldo, R. L.

1978-01-01

The preliminary results of simulated electric vehicle, chopper, speed controller discharge of a battery show energy output losses up to 25 percent compared to constant current discharges at the same average discharge current of 100 amperes. These energy losses are manifested as temperature rises during discharge, amounting to a two-fold increase for a 400-ampere pulse compared to the constant current case. Because of the potentially large energy inefficiency, the results suggest that electric vehicle battery/speed controller interaction must be carefully considered in vehicle design.

Response of lead-acid batteries to chopper-controlled discharge

NASA Technical Reports Server (NTRS)

Cataldo, R. L.

1978-01-01

The preliminary results of simulated electric vehicle, chopper, speed controller discharge of a battery show energy output losses at up to 25 percent compared to constant current discharges at the same average discharge current of 100 A. These energy losses are manifested as temperature rises during discharge, amounting to a two-fold increase for a 400-A pulse compared to the constant current case. Because of the potentially large energy inefficiency, the results suggest that electric vehicle battery/speed controller interaction must be carefully considered in vehicle design.

Grid regulation services for energy storage devices based on grid frequency

DOEpatents

Pratt, Richard M; Hammerstrom, Donald J; Kintner-Meyer, Michael C.W.; Tuffner, Francis K

2013-07-02

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

Grid regulation services for energy storage devices based on grid frequency

DOEpatents

Pratt, Richard M.; Hammerstrom, Donald J.; Kintner-Meyer, Michael C. W.; Tuffner, Francis K.

2017-09-05

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

Grid regulation services for energy storage devices based on grid frequency

DOEpatents

Pratt, Richard M; Hammerstrom, Donald J; Kintner-Meyer, Michael C.W.; Tuffner, Francis K

2014-04-15

Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

Tritium leak triggers reactor shutdown in the US

NASA Astrophysics Data System (ADS)

Gwynne, Peter

2010-04-01

A US state has voted against renewing the operating licence for its only working nuclear reactor after a leak of tritium was found in the 38-year-old power plant. The decision in late February by Vermont's senate to close the 650 MW Vermont Yankee reactor has cast a shadow over the Obama administration's plans to encourage the construction of more nuclear power plants to meet the country's increasing electricity demands. The plant currently provides one-third of the state's electricity demands.

Metod And Apparatus For Debris Mitigation For An Electrical Discharge Source

DOEpatents

Klebanoff, Leonard E.; Silfvast, William T.; Rader, Daniel J.

2005-05-03

Method and apparatus for mitigating the transport of debris generated and dispersed from electric discharge sources by thermophoretic and electrostatic deposition. A member is positioned adjacent the front electrode of an electric discharge source and used to establish a temperature difference between it and the front electrode. By flowing a gas between the member and the front electrode a temperature gradient is established that can be used for thermophoretic deposition of particulate debris on either the member or front electrode depending upon the direction of the thermal gradient. Establishing an electric field between the member and front electrode can aid in particle deposition by electrostatic deposition.

Method and apparatus for debris mitigation for an electrical discharge source

DOEpatents

Klebanoff, Leonard E [San Clemente, CA; Rader, Daniel J [Albuquerque, NM; Silfvast, William T [Helena, CA

2006-01-24

Method and apparatus for mitigating the transport of debris generated and dispersed from electric discharge sources by thermophoretic and electrostatic deposition. A member is positioned adjacent the front electrode of an electric discharge source and used to establish a temperature difference between it and the front electrode. By flowing a gas between the member and the front electrode a temperature gradient is established that can be used for thermophoretic deposition of particulate debris on either the member or front electrode depending upon the direction of the thermal gradient. Establishing an electric field between the member and front electrode can aid in particle deposition by electrostatic deposition.

46 CFR 108.437 - Pipe sizes and discharge rates for enclosed ventilation systems for rotating electrical equipment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Pipe sizes and discharge rates for enclosed ventilation... Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.437 Pipe sizes and discharge rates for enclosed ventilation systems for rotating electrical equipment. (a) The minimum pipe size for the initial...

46 CFR 108.437 - Pipe sizes and discharge rates for enclosed ventilation systems for rotating electrical equipment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Pipe sizes and discharge rates for enclosed ventilation systems for rotating electrical equipment. 108.437 Section 108.437 Shipping COAST GUARD, DEPARTMENT OF... Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.437 Pipe sizes and discharge rates for...

Plasma discharge self-cleaning filtration system

DOEpatents

Cho, Young I.; Fridman, Alexander; Gutsol, Alexander F.; Yang, Yong

2014-07-22

The present invention is directed to a novel method for cleaning a filter surface using a plasma discharge self-cleaning filtration system. The method involves utilizing plasma discharges to induce short electric pulses of nanoseconds duration at high voltages. These electrical pulses generate strong Shockwaves that disintegrate and dislodge particulate matter located on the surface of the filter.

The shocking predatory strike of the electric eel.

PubMed

Catania, Kenneth

2014-12-05

Electric eels can incapacitate prey with an electric discharge, but the mechanism of the eel's attack is unknown. Through a series of experiments, I show that eel high-voltage discharges can activate prey motor neurons, and hence muscles, allowing eels to remotely control their target. Eels prevent escape in free-swimming prey using high-frequency volleys to induce immobilizing whole-body muscle contraction (tetanus). Further, when prey are hidden, eels can emit periodic volleys of two or three discharges that cause massive involuntary twitch, revealing the prey's location and eliciting the full, tetanus-inducing volley. The temporal patterns of eel electrical discharges resemble motor neuron activity that induces fast muscle contraction, suggesting that eel high-voltage volleys have been selected to most efficiently induce involuntary muscle contraction in nearby animals. Copyright © 2014, American Association for the Advancement of Science.

Peaceful Uses of Fusion

DOE R&D Accomplishments Database

Teller, E.

1958-07-03

Applications of thermonuclear energy for peaceful and constructive purposes are surveyed. Developments and problems in the release and control of fusion energy are reviewed. It is pointed out that the future of thermonuclear power reactors will depend upon the construction of a machine that produces more electric energy than it consumes. The fuel for thermonuclear reactors is cheap and practically inexhaustible. Thermonuclear reactors produce less dangerous radioactive materials than fission reactors and, when once brought under control, are not as likely to be subject to dangerous excursions. The interaction of the hot plasma with magnetic fields opens the way for the direct production of electricity. It is possible that explosive fusion energy released underground may be harnessed for the production of electricity before the same feat is accomplished in controlled fusion processes. Applications of underground detonations of fission devices in mining and for the enhancement of oil flow in large low-specific-yield formations are also suggested.

Social interactions between live and artificial weakly electric fish: Electrocommunication and locomotor behavior of Mormyrus rume proboscirostris towards a mobile dummy fish

PubMed Central

Kirschbaum, Frank; von der Emde, Gerhard

2017-01-01

Mormyrid weakly electric fish produce short, pulse-type electric organ discharges for actively probing their environment and to communicate with conspecifics. Animals emit sequences of pulse-trains that vary in overall frequency and temporal patterning and can lead to time-locked interactions with the discharge activity of other individuals. Both active electrolocation and electrocommunication are additionally accompanied by stereotypical locomotor patterns. However, the concrete roles of electrical and locomotor patterns during social interactions in mormyrids are not well understood. Here we used a mobile fish dummy that was emitting different types of electrical playback sequences to study following behavior and interaction patterns (electrical and locomotor) between individuals of weakly electric fish. We confronted single individuals of Mormyrus rume proboscirostris with a mobile dummy fish designed to attract fish from a shelter and recruit them into an open area by emitting electrical playbacks of natural discharge sequences. We found that fish were reliably recruited by the mobile dummy if it emitted electrical signals and followed it largely independently of the presented playback patterns. While following the dummy, fish interacted with it spatially by displaying stereotypical motor patterns, as well as electrically, e.g. through discharge regularizations and by synchronizing their own discharge activity to the playback. However, the overall emission frequencies of the dummy were not adopted by the following fish. Instead, social signals based on different temporal patterns were emitted depending on the type of playback. In particular, double pulses were displayed in response to electrical signaling of the dummy and their expression was positively correlated with an animals' rank in the dominance hierarchy. Based on additional analysis of swimming trajectories and stereotypical locomotor behavior patterns, we conclude that the reception and emission of electrical communication signals play a crucial role in mediating social interactions in mormyrid weakly electric fish. PMID:28902915

76 FR 68514 - Request for a License To Export Reactor Components

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-04

... NUCLEAR REGULATORY COMMISSION Request for a License To Export Reactor Components Pursuant to 10.../docket Number Westinghouse Electric Company Complete reactor 12 Perform seismic China. LLC, August 18... qualification equipment. of AP1000 (design) nuclear reactors. For the Nuclear Regulatory Commission. Dated this...

Electric field strength determination in filamentary DBDs by CARS-based four-wave mixing

NASA Astrophysics Data System (ADS)

Boehm, Patrick; Kettlitz, Manfred; Brandenburg, Ronny; Hoeft, Hans; Czarnetzki, Uwe

2016-09-01

The electric field strength is a basic parameter of non-thermal plasmas. Therefore, a profound knowledge of the electric field distribution is crucial. In this contribution a four wave mixing technique based on Coherent Anti-Stokes Raman spectroscopy (CARS) is used to measure electric field strengths in filamentary dielectric barrier discharges (DBDs). The discharges are operated with a pulsed voltage in nitrogen at atmospheric pressure. Small amounts hydrogen (10 vol%) are admixed as tracer gas to evaluate the electric field strength in the 1 mm discharge gap. Absolute values of the electric field strength are determined by calibration of the CARS setup with high voltage amplitudes below the ignition threshold of the arrangement. Alteration of the electric field strength has been observed during the internal polarity reversal and the breakdown process. In this case the major advantage over emission based methods is that this technique can be used independently from emission, e.g. in the pre-phase and in between two consecutive, opposite discharge pulses where no emission occurs at all. This work was supported by the Deutsche Forschungsgemeinschaft, Forschergruppe FOR 1123 and Sonderforschungsbereich TRR 24 ``Fundamentals of complex plasmas''.

PROCESS WATER BUILDING, TRA605, INTERIOR. FIRST FLOOR. ELECTRICAL EQUIPMENT IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PROCESS WATER BUILDING, TRA-605, INTERIOR. FIRST FLOOR. ELECTRICAL EQUIPMENT IN LEFT HALF OF VIEW. CAMERA IS IN NORTHWEST CORNER FACING SOUTHEAST. INL NEGATIVE NO. HD46-27-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

ETR, TRA642. ELEVATIONS. METAL SIDING. OFFICE BUILDING (TRA647) AND ELECTRICAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR, TRA-642. ELEVATIONS. METAL SIDING. OFFICE BUILDING (TRA-647) AND ELECTRICAL BUILDING (TRA-648) ATTACHED. KAISER ETR-5528-MTR-642-A-11, 11/1955. INL INDEX NO. 532-0642-00-486-100919, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

ETR, TRA642. WALL SECTION DETAILS. METAL SIDING JOINS TO ELECTRICAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR, TRA-642. WALL SECTION DETAILS. METAL SIDING JOINS TO ELECTRICAL BUILDING, OFFICE BUILDING, AND ROOF. KAISER ETR-5528-MTR-A-13, 11/1955. INL INDEX NO. 532-0642-00-486-100920, REV. 4. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

76 FR 52715 - Advisory Committee on Reactor Safeguards (ACRS); Meeting of the ACRS Subcommittee on Regulatory...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-23

... review Draft Final Regulatory Guide (RG) 1.93, ``Availability of Electric Power Sources,'' Revision 1 and new Draft Final RG 1.218, ``Condition Monitoring Techniques for Electric Cables Used in Nuclear Power... NUCLEAR REGULATORY COMMISSION Advisory Committee on Reactor Safeguards (ACRS); Meeting of the ACRS...

Mechanism of singlet oxygen deactivation in an electric discharge oxygen – iodine laser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Azyazov, V N; Mikheyev, P A; Torbin, A P

2014-12-31

We have determined the influence of the reaction of molecular singlet oxygen with a vibrationally excited ozone molecule O{sub 2}(a {sup 1}Δ) + O{sub 3}(ν) → 2O{sub 2} + O on the removal rate of O{sub 2}(a {sup 1}Δ) in an electric-discharge-driven oxygen – iodine laser. This reaction has been shown to be a major channel of O{sub 2}(a {sup 1}Δ) loss at the output of an electric-discharge singlet oxygen generator. In addition, it can also contribute significantly to the loss of O{sub 2}(a {sup 1}Δ) in the discharge region of the generator. (lasers)

Alternative approaches to fusion. [reactor design and reactor physics for Tokamak fusion reactors

NASA Technical Reports Server (NTRS)

Roth, R. J.

1976-01-01

The limitations of the Tokamak fusion reactor concept are discussed and various other fusion reactor concepts are considered that employ the containment of thermonuclear plasmas by magnetic fields (i.e., stellarators). Progress made in the containment of plasmas in toroidal devices is reported. Reactor design concepts are illustrated. The possibility of using fusion reactors as a power source in interplanetary space travel and electric power plants is briefly examined.

Partial discharge characteristics of polymer nanocomposite materials in electrical insulation: a review of sample preparation techniques, analysis methods, potential applications, and future trends.

PubMed

Izzati, Wan Akmal; Arief, Yanuar Z; Adzis, Zuraimy; Shafanizam, Mohd

2014-01-01

Polymer nanocomposites have recently been attracting attention among researchers in electrical insulating applications from energy storage to power delivery. However, partial discharge has always been a predecessor to major faults and problems in this field. In addition, there is a lot more to explore, as neither the partial discharge characteristic in nanocomposites nor their electrical properties are clearly understood. By adding a small amount of weight percentage (wt%) of nanofillers, the physical, mechanical, and electrical properties of polymers can be greatly enhanced. For instance, nanofillers in nanocomposites such as silica (SiO2), alumina (Al2O3) and titania (TiO2) play a big role in providing a good approach to increasing the dielectric breakdown strength and partial discharge resistance of nanocomposites. Such polymer nanocomposites will be reviewed thoroughly in this paper, with the different experimental and analytical techniques used in previous studies. This paper also provides an academic review about partial discharge in polymer nanocomposites used as electrical insulating material from previous research, covering aspects of preparation, characteristics of the nanocomposite based on experimental works, application in power systems, methods and techniques of experiment and analysis, and future trends.

46 CFR 169.692 - Remote stop stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Machinery and Electrical Electrical Installations on Vessels of 100 Gross Tons and Over § 169.692 Remote... propulsion unit, (b) A bilge slop or dirty oil discharge shutdown at the deck discharge, (c) A ventilation...

Transverse-type laser assembly using induced electrical discharge excitation and method

DOEpatents

Ault, Earl R.

1994-01-01

A transverse-type laser assembly is disclosed herein. This assembly defines a laser cavity containing a vapor or gaseous substance which lases when subjected to specific electrical discharge excitation between a pair of spaced-apart electrodes located within the cavity in order to produce a source of light. An arrangement located entirely outside the laser cavity is provided for inducing a voltage across the electrodes within the cavity sufficient to provide the necessary electrical discharge excitation to cause a vapor substance between the electrodes to lase.

Transverse-type laser assembly using induced electrical discharge excitation and method

DOEpatents

Ault, E.R.

1994-04-19

A transverse-type laser assembly is disclosed herein. This assembly defines a laser cavity containing a vapor or gaseous substance which lases when subjected to specific electrical discharge excitation between a pair of spaced-apart electrodes located within the cavity in order to produce a source of light. An arrangement located entirely outside the laser cavity is provided for inducing a voltage across the electrodes within the cavity sufficient to provide the necessary electrical discharge excitation to cause a vapor substance between the electrodes to lase. 3 figures.

Zero Discharge Performance of an Industrial Pilot-Scale Plant Treating Palm Oil Mill Effluent

PubMed Central

Mahmood, Qaisar; Qiu, Jiang-Ping; Li, Yin-Sheng; Chang, Yoon-Seong; Chi, Li-Na; Li, Xu-Dong

2015-01-01

Palm oil is one of the most important agroindustries in Malaysia. Huge quantities of palm oil mill effluent (POME) pose a great threat to aqueous environment due to its very high COD. To make full use of discharged wastes, the integrated “zero discharge” pilot-scale industrial plant comprising “pretreatment-anaerobic and aerobic process-membrane separation” was continuously operated for 1 year. After pretreatment in the oil separator tank, 55.6% of waste oil in raw POME could be recovered and sold and anaerobically digested through 2 AnaEG reactors followed by a dissolved air flotation (DAF); average COD reduced to about 3587 mg/L, and biogas production was 27.65 times POME injection which was used to generate electricity. The aerobic effluent was settled for 3 h or/and treated in MBR which could remove BOD3 (30°C) to less than 20 mg/L as required by Department of Environment of Malaysia. After filtration by UF and RO membrane, all organic compounds and most of the salts were removed; RO permeate could be reused as the boiler feed water. RO concentrate combined with anaerobic surplus sludge could be used as biofertilizer. PMID:25685798

Simulated nuclear reactor fuel assembly

DOEpatents

Berta, V.T.

1993-04-06

An apparatus for electrically simulating a nuclear reactor fuel assembly. It includes a heater assembly having a top end and a bottom end and a plurality of concentric heater tubes having electrical circuitry connected to a power source, and radially spaced from each other. An outer target tube and an inner target tube is concentric with the heater tubes and with each other, and the outer target tube surrounds and is radially spaced from the heater tubes. The inner target tube is surrounded by and radially spaced from the heater tubes and outer target tube. The top of the assembly is generally open to allow for the electrical power connection to the heater tubes, and the bottom of the assembly includes means for completing the electrical circuitry in the heater tubes to provide electrical resistance heating to simulate the power profile in a nuclear reactor. The embedded conductor elements in each heater tube is split into two halves for a substantial portion of its length and provided with electrical isolation such that each half of the conductor is joined at one end and is not joined at the other end.

Simulated nuclear reactor fuel assembly

DOEpatents

Berta, Victor T.

1993-01-01

An apparatus for electrically simulating a nuclear reactor fuel assembly. It includes a heater assembly having a top end and a bottom end and a plurality of concentric heater tubes having electrical circuitry connected to a power source, and radially spaced from each other. An outer target tube and an inner target tube is concentric with the heater tubes and with each other, and the outer target tube surrounds and is radially spaced from the heater tubes. The inner target tube is surrounded by and radially spaced from the heater tubes and outer target tube. The top of the assembly is generally open to allow for the electrical power connection to the heater tubes, and the bottom of the assembly includes means for completing the electrical circuitry in the heater tubes to provide electrical resistance heating to simulate the power profile in a nuclear reactor. The embedded conductor elements in each heater tube is split into two halves for a substantial portion of its length and provided with electrical isolation such that each half of the conductor is joined at one end and is not joined at the other end.

Treatment of Dyeing Wastewater by Using Positive Pulsed Corona Discharge to Water Surface

NASA Astrophysics Data System (ADS)

Young, Sun Mok; Hyun, Tae Ahn; Joeng, Tai Kim

2007-02-01

This study investigated the treatment of textile-dyeing wastewater by using an electrical discharge technique (positive pulsed corona discharge). The high-voltage electrode was placed above the surface of the wastewater while the ground electrode was submerged in the wastewater. The electrical discharge starting at the tip of the high voltage electrode propagated toward the surface of the wastewater, producing various oxidative radicals and ozone. Oxygen was used as the working gas instead of air to prevent nitrogen oxides from forming. The simulated wastewater was made up with amaranth, which is a kind of azo dye. The results obtained showed that the chromaticity of the wastewater was almost completely removed within an hour. The ultraviolet/visible spectra of the wastewater treated by the electrical discharge revealed that the total hydrocarbon level also decreased significantly.

Pulsed high voltage electric discharge disinfection of microbially contaminated liquids.

PubMed

Anpilov, A M; Barkhudarov, E M; Christofi, N; Kop'ev, V A; Kossyi, I A; Taktakishvili, M I; Zadiraka, Y

2002-01-01

To examine the use of a novel multielectrode slipping surface discharge (SSD) treatment system, capable of pulsed plasma discharge directly in water, in killing micro-organisms. Potable water containing Escherichia coli and somatic coliphages was treated with pulsed electric discharges generated by the SSD. The SSD system was highly efficient in the microbial disinfection of water with a low energy utilization (eta approximately 10-4 kW h l-1). The SSD treatment was effective in the destruction of E. coli and its coliphages through the generation of u.v. radiation, ozone and free radicals. The non-thermal treatment method can be used for the eradication of micro-organisms in a range of contaminated liquids, including milk, negating the use of pasteurization. The method utilizes multipoint electric discharges capable of treating large volumes of liquid under static and flowing regimes.

A pulser-sustainer carbon monoxide electric-discharge supersonic laser

NASA Technical Reports Server (NTRS)

Monson, D. J.; Srinivasan, G.

1977-01-01

Operation of a CW CO electric-discharge supersonic laser with a pulser-sustainer discharge is described. High-power operation as well as independent control over electron energy and density are demonstrated. Maximum input power achieved to date is 100 kW. The maximum output power is 6 kW or 10% of the sustainer positive-column power. Much improved performance appears possible.

The use of dual mode thermionic reactors in supporting Earth orbital and space exploration missions

NASA Astrophysics Data System (ADS)

Zubrin, Robert M.; Sulmeisters, Tal K.

1993-01-01

Missions requiring large amounts of electric power to support their payload functions can be enabled through the employment of nuclear electric power reactors, which in some cases can also assist the mission by making possible the employment of high specific impulse electric propulsion. However it is found that the practicality and versality of using a power reactor to provide advanced propulsion is enormously enhanced if the reactor is configured in such a way to allow it to generate a certain amount of direct thrust as well. The use of such a system allows the creation of a common bus upper stage that can provide both high power and high impulse (with short orbit transfer times). It is shown that such a system, termed an Integral Power and Propulsion Stage (IPAPS), is optimal for supporting many Earth, Lunar, planetary and asteroidal observation, exploration, and communication support missions, and it is therefore recommended that the nuclear power reactor ultimately selected by the government for development and production be one that can be configured for such a function.

An adaptive load-following control system for a space nuclear power system

NASA Astrophysics Data System (ADS)

Metzger, John D.; El-Genk, Mohamed S.

An adaptive load-following control system is proposed for a space nuclear power system. The conceptual design of the SP-100 space nuclear power system proposes operating the nuclear reactor at a base thermal power and accommodating changes in the electrical power demand with a shunt regulator. It is necessary to increase the reactor thermal power if the payload electrical demand exceeds the peak system electrical output for the associated reactor power. When it is necessary to change the nuclear reactor power to meet a change in the power demand, the power ascension or descension must be accomplished in a predetermined manner to avoid thermal stresses in the system and to achieve the desired reactor period. The load-following control system described has the ability to adapt to changes in the system and to changes in the satellite environment. The application is proposed of the model reference adaptive control (MRAC). The adaptive control system has the ability to control the dynamic response of nonlinear systems. Three basic subsets of adaptive control are: (1) gain scheduling, (2) self-tuning regulators, and (3) model reference adaptive control.

Control of electromagnetic edge effects in electrically-small rectangular plasma reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trampel, Christopher P.; Stieler, Daniel S.; PowerFilm, Inc., 2337 230th Street, Ames, Iowa 50014

Electromagnetic fields supported by rectangular reactors for plasma enhanced chemical vapor deposition are studied theoretically. Expressions for the fields in an electrically-small rectangular reactor with plasma in the chamber are derived. Modal field decompositions are employed under the homogeneous plasma slab approximation. The amplitude of each mode is determined analytically. It is shown that the field can be represented by the standing wave, evanescent waves tied to the edges, and an evanescent wave tied to the corners of the reactor. The impact of boundary conditions at the plasma edge on nonuniformity is quantified. Uniformity may be improved by placing amore » lossy magnetic layer on the reactor sidewalls. It is demonstrated that nonuniformity is a decreasing function of layer thickness.« less

A Boiling-Potassium Fluoride Reactor for an Artificial-Gravity NEP Vehicle

NASA Technical Reports Server (NTRS)

Sorensen, Kirk; Juhasz, Albert

2007-01-01

Several years ago a rotating manned spacecraft employing nuclear-electric propulsion was examined for Mars exploration. The reactor and its power conversion system essentially served as the counter-mass to an inflatable manned module. A solid-core boiling potassium reactor based on the MPRE concept of the 1960s was baselined in that study. This paper proposes the use of a liquid-fluoride reactor, employing direct boiling of potassium in the core, as a means to overcome some of the residual issues with the MPRE reactor concept. Several other improvements to the rotating Mars vehicle are proposed as well, such as Canfield joints to enable the electric engines to track the inertial thrust vector during rotation, and innovative "cold-ion" engine technologies to improve engine performance.

Phenol degradation by TiO2 photocatalysts combined with different pulsed discharge systems.

PubMed

Zhang, Yi; Lu, Jiani; Wang, Xiaoping; Xin, Qing; Cong, Yanqing; Wang, Qi; Li, Chunjuan

2013-11-01

Films of TiO2 nanotubes distributed over the inner surface of a discharge reactor cylinder (CTD) or adhered to a stainless steel electrode surface (PTD) in a discharge reactor were compared with a single-discharge (SD) system to investigate their efficiencies in phenol degradation. Morphology studies indicated that the TiO2 film was destroyed in the PTD system, but that there was no change in the CTD system after discharge. X-ray diffraction results revealed that the anatase phase of the original sample was preserved in the CTD system, but that an anatase-to-rutile phase transformation occurred in the PTD system after discharge. The highest efficiencies of phenol degradation and total organic carbon (TOC) mineralization were observed in the CTD system, and there was no decrease in phenol degradation efficiency upon reuse of a TiO2 film, indicating high catalysis activity and stability of the TiO2 photocatalysts in the combined treatment. TiO2 photocatalysts favored the formation of hydrogen peroxide and disfavored the formation of ozone. A greater degree of oxidation of intermediates and higher energy efficiency in phenol oxidation were observed with the TiO2-plasma systems, especially in the CTD system, compared to those with the SD system. Copyright © 2013 Elsevier Inc. All rights reserved.

Tritium ((3)H) as a tracer for monitoring the dispersion of conservative radionuclides discharged by the Angra dos Reis nuclear power plants in the Piraquara de Fora Bay, Brazil.

PubMed

de Carvalho Gomes, Franciane; Godoy, José Marcus; de Carvalho, Zenildo Lara; de Souza, Elder Magalhães; Rodrigues Silva, José Ivan; Tadeu Lopes, Ricardo

2014-10-01

Presently, two nuclear power plants operate in Brazil. Both are located at Itaorna beach, Angra dos Reis, approximately 133 km from Rio de Janeiro city. The reactor cooling circuits require the input of seawater, which is later discharged through a pipeline into the adjacent Piraquara de Fora Cove. The radioactive effluents undergo ion-exchange treatment prior to their release in batches, causing the enrichment of (3)H relative to other radionuclides in the discharged waters. Under steady state conditions, the (3)H gradient in the Piraquara de Fora waters can be used to determine the dependence of the dilution factor on the distance from the discharge point. The present work describes experiments carried out at the reactor site during batch release episodes, including time series sampling at the discharge point and surface seawater sampling every 250 m to a distance of 1250 m, after a double distillation, the (3)H concentration was measured by liquid scintillation counting applying a Quantulus liquid scintillation spectrometer. The obtained results showed a linear relationship between the (3)H concentration and distance from the discharge point. At 1250 m from the discharge point a dilution index of 1:15 was measured which fits the expected value based on modeling. Copyright © 2014 Elsevier Ltd. All rights reserved.

Pratt & Whitney ESCORT derivative for mars surface power

NASA Astrophysics Data System (ADS)

Feller, Gerald J.; Joyner, Russell

1999-01-01

The purpose of this paper is to address the applicability of a common reactor system design from the Pratt & Whitney ESCORT nuclear thermal rocket engine concept to support current NASA mars surface-based power requirements. The ESCORT is a bimodal engine capable of supporting a wide range of propulsive thermal and vehicle electrical power requirements. The ESCORT engine is powered by a fast-spectrum beryllium-reflected CERMET-fueled nuclear reactor. In addition to an expander cycle propulsive mode, the ESCORT is capable of operating in an electrical power mode. In this mode, the reactor is used to heat a mixture of helium and xenon to drive a closed-loop Brayton cycle in order to generate electrical energy. Recent Design Reference Mission requirements (DRM) from NASA Johnson Space Center and NASA Lewis Research Center studies in 1997 and 1998 have detailed upgraded requirements for potential mars transfer missions. The current NASA DRM requires a nuclear thermal propulsion system capable of delivering total mission requirements of 200170 N (45000 lbf) thrust and 50 kWe of spacecraft electrical power. Additionally, these requirements detailed a surface power system capable of providing approximately 160 kW of electrical energy over an approximate 10 year period within a given weight and volume envelope. Current NASA studies use a SP-100 reactor (0.8 MT) and a NERVA derivative (1.6 MT) as baseline systems. A mobile power cart of approximate dimensions 1.7 m×4.5 m×4.4 m has been conceptualized to transport the reactor power system on the Mars Surface. The 63.25 cm diameter and 80.25 cm height of the ESCORT and its 1.3 MT of weight fit well within the current weight and volume target range of the NASA DRM requirements. The modifications required to the ESCORT reactor system to support this upgraded electrical power requirements along with operation in the Martian atmospheric conditions are addressed in this paper. Sufficient excess reactivity and burnup capability were designed into the ESCORT reactor system to support these upgraded requirements. Only slight modifications to reactor hardware were required to address any environmental considerations. These modifications involved sealing any refractory metal alloy components from the CO2 in the Martian Atmosphere. Also, the Brayton cycle Power Conversion Unit (PCU) hardware was modified to support the upgraded requirements. This paper discusses the design analysis performed and provides information on the final common reactor concept to be used on the Mars surface to support manned missions.

The Effects of Self-Discharge on the Performance of Symmetric Electric Double-Layer Capacitors and Active Electrolyte-Enhanced Supercapacitors: Insights from Modeling and Simulation

NASA Astrophysics Data System (ADS)

Ike, Innocent S.; Sigalas, Iakovos; Iyuke, Sunny E.

2017-02-01

The effects of self-discharge on the performance of symmetric electric double-layer capacitors (EDLCs) and active electrolyte-enhanced supercapacitors were examined by incorporating self-discharge into electrochemical capacitor models during charging and discharging. The sources of self-discharge in capacitors were side reactions or redox reactions and several impurities and electric double-layer (EDL) instability. The effects of self-discharge during capacitor storage was negligible since it took a fully charged capacitor a minimum of 14.0 days to be entirely discharged by self-discharge in all conditions studied, hence self-discharge in storage condition can be ignored. The first and second charge-discharge cycle energy efficiencies η_{{{{E}}1}} and η_{{{{E}}2}} of a capacitor of electrode effective conductivity α1 = 0.05 S/cm with only EDL instability self-discharge with current density J_{{VR}} = 1.25 × 10-3 A/cm2 were 72.33% and 72.34%, respectively. Also, energy efficiencies η_{{{{E}}1}} and η_{{{{E}}2}} of a similar capacitor with both side reactions and redox reactions and EDL instability self-discharges with current densities J_{{VR}} = 0.00125 A/cm2 and J_{{{{VR}}1}} = 0.0032 A/cm2 were 38.13% and 38.14% respectively, compared with 84.24% and 84.25% in a similar capacitor without self-discharge. A capacitor with only EDL instability self-discharge and that with both side reactions and redox reactions and EDL instability self-discharge lost 9.73 Wh and 28.38 Wh of energy, respectively, through self-discharge during charging and discharging. Hence, EDLCs charging and discharging time is significantly dependent on the self-discharge rate which are too large to be ignored.

Laboratory simulation of irradiation-induced dielectric breakdown in spacecraft charging

NASA Technical Reports Server (NTRS)

Yadlowsky, E. J.; Churchill, R. J.; Hazelton, R. C.

1980-01-01

The discharging of dielectric samples irradiated by a beam of monoenergetic electrons is investigated. The development of a model, or models, which describe the discharge phenomena occuring on the irradiated dielectric targets is discussed. The electrical discharge characteristics of irradiated dielectric samples are discussed and the electrical discharge paths along dielectric surfaces and within the dielectric material are determined. The origin and destination of the surface emitted particles is examined and the charge and energy balance in the system is evaluated.

Branching Patterns and Stepped Leaders in an Electric-Circuit Model for Creeping Discharge

NASA Astrophysics Data System (ADS)

Hidetsugu Sakaguchi,; Sahim M. Kourkouss,

2010-06-01

We construct a two-dimensional electric circuit model for creeping discharge. Two types of discharge, surface corona and surface leader, are modeled by a two-step function of conductance. Branched patterns of surface leaders surrounded by the surface corona appear in numerical simulation. The fractal dimension of branched discharge patterns is calculated by changing voltage and capacitance. We find that surface leaders often grow stepwise in time, as is observed in lightning leaders of thunder.

NPDES Permit for Potomac Electric Power Company (PEPCO) Benning Generating Station

EPA Pesticide Factsheets

Under National Pollutant Discharge Elimination System permit number DC0000094, the Potomac Electric Power Company (PEPCO) Benning Generating Station is authorized to discharge from from a facility to receiving waters named Anacostia River.

Mathematical model of optical signals emitted by electrical discharges occuring in electroinsulating oil

NASA Astrophysics Data System (ADS)

Kozioł, Michał

2017-10-01

The article presents a parametric model describing the registered distributions spectrum of optical radiation emitted by electrical discharges generated in the systems: the needle- needle, the needleplate and in the system for surface discharges. Generation of electrical discharges and registration of the emitted radiation was carried out in three different electrical insulating oils: fabric new, operated (used) and operated with air bubbles. For registration of optical spectra in the range of ultraviolet, visible and near infrared a high resolution spectrophotometer was. The proposed mathematical model was developed in a regression procedure using gauss-sigmoid type function. The dependent variable was the intensity of the recorded optical signals. In order to estimate the optimal parameters of the model an evolutionary algorithm was used. The optimization procedure was performed in Matlab environment. For determination of the matching quality of theoretical parameters of the regression function to the empirical data determination coefficient R2 was applied.

Micro electrical discharge milling using deionized water as a dielectric fluid

NASA Astrophysics Data System (ADS)

Chung, Do Kwan; Kim, Bo Hyun; Chu, Chong Nam

2007-05-01

In electrical discharge machining, dielectric fluid is an important factor affecting machining characteristics. Generally, kerosene and deionized water have been used as dielectric fluids. In micro electrical discharge milling, which uses a micro electrode as a tool, the wear of the tool electrode decreases the machining accuracy. However, the use of deionized water instead of kerosene can reduce the tool wear and increase the machining speed. This paper investigates micro electrical discharge milling using deionized water. Deionized water with high resistivity was used to minimize the machining gap. Machining characteristics such as the tool wear, machining gap and machining rate were investigated according to resistivity of deionized water. As the resistivity of deionized water decreased, the tool wear was reduced, but the machining gap increased due to electrochemical dissolution. Micro hemispheres were machined for the purpose of investigating machining efficiency between dielectric fluids, kerosene and deionized water.

Electric charging/discharging characteristics of super capacitor, using de-alloying and anodic oxidized Ti-Ni-Si amorphous alloy ribbons.

PubMed

Fukuhara, Mikio; Sugawara, Kazuyuki

2014-01-01

Charging/discharging behaviors of de-alloyed and anodic oxidized Ti-Ni-Si amorphous alloy ribbons were measured as a function of current between 10 pA and 100 mA, using galvanostatic charge/discharging method. In sharp contrast to conventional electric double layer capacitor (EDLC), discharging behaviors for voltage under constant currents of 1, 10 and 100 mA after 1.8 ks charging at 100 mA show parabolic decrease, demonstrating direct electric storage without solvents. The supercapacitors, devices that store electric charge on their amorphous TiO2-x surfaces that contain many 70-nm sized cavities, show the Ragone plot which locates at lower energy density region near the 2nd cells, and RC constant of 800 s (at 1 mHz), which is 157,000 times larger than that (5 ms) in EDLC.

Electric charging/discharging characteristics of super capacitor, using de-alloying and anodic oxidized Ti-Ni-Si amorphous alloy ribbons

PubMed Central

2014-01-01

Charging/discharging behaviors of de-alloyed and anodic oxidized Ti-Ni-Si amorphous alloy ribbons were measured as a function of current between 10 pA and 100 mA, using galvanostatic charge/discharging method. In sharp contrast to conventional electric double layer capacitor (EDLC), discharging behaviors for voltage under constant currents of 1, 10 and 100 mA after 1.8 ks charging at 100 mA show parabolic decrease, demonstrating direct electric storage without solvents. The supercapacitors, devices that store electric charge on their amorphous TiO2-x surfaces that contain many 70-nm sized cavities, show the Ragone plot which locates at lower energy density region near the 2nd cells, and RC constant of 800 s (at 1 mHz), which is 157,000 times larger than that (5 ms) in EDLC. PMID:24959106

Distribution of E/N and N/e/ in a cross-flow electric discharge laser. [electric field to neutral gas density and electron number density

NASA Technical Reports Server (NTRS)

Dunning, J. W., Jr.; Lancashire, R. B.; Manista, E. J.

1976-01-01

Measurements have been conducted of the effect of the convection of ions and electrons on the discharge characteristics in a large scale laser. The results are presented for one particular distribution of ballast resistance. Values of electric field, current density, input power density, ratio of electric field to neutral gas density (E/N), and electron number density were calculated on the basis of measurements of the discharge properties. In a number of graphs, the E/N ratio, current density, power density, and electron density are plotted as a function of row number (downstream position) with total discharge current and gas velocity as parameters. From the dependence of the current distribution on the total current, it appears that the electron production in the first two rows significantly affects the current flowing in the succeeding rows.

Electric field in a plasma channel in a high-pressure nanosecond discharge in hydrogen: a coherent anti-stokes Raman scattering study.

PubMed

Yatom, S; Tskhai, S; Krasik, Ya E

2013-12-20

Experimental results of a study of the electric field in a plasma channel produced during nanosecond discharge at a H2 gas pressure of (2-3)×10(5)  Pa by the coherent anti-Stokes scattering method are reported. The discharge was ignited by applying a voltage pulse with an amplitude of ∼100  kV and a duration of ∼5  ns to a blade cathode placed at a distance of 10 and 20 mm from the anode. It was shown that this type of gas discharge is characterized by the presence of an electric field in the plasma channel with root-mean-square intensities of up to 30  kV/cm. Using polarization measurements, it was found that the direction of the electric field is along the cathode-anode axis.

The future of nuclear power: A world-wide perspective

NASA Astrophysics Data System (ADS)

Aktar, Ismail

This study analyzes the future of commercial nuclear electric generation worldwide using the Environmental Kuznets Curve (EKC) concept. The Tobit panel data estimation technique is applied to analyze the data between 1980 and 1998 for 105 countries. EKC assumes that low-income countries increase their nuclear reliance in total electric production whereas high-income countries decrease their nuclear reliance. Hence, we expect that high-income countries should shut down existing nuclear reactors and/or not build any new ones. We encounter two reasons for shutdowns: economic or political/environmental concerns. To distinguish these two effects, reasons for shut down are also investigated by using the Hazard Model technique. Hence, the load factor of a reactor is used as an approximation for economic reason to shut down the reactor. If a shut downed reactor had high load factor, this could be attributable to political/environmental concern or else economic concern. The only countries with nuclear power are considered in this model. The two data sets are created. In the first data set, the single entry for each reactor is created as of 1998 whereas in the second data set, the multiple entries are created for each reactor beginning from 1980 to 1998. The dependent variable takes 1 if operational or zero if shut downed. The empirical findings provide strong evidence for EKC relationship for commercial nuclear electric generation. Furthermore, higher natural resources suggest alternative electric generation methods rather than nuclear power. Economic index as an institutional variable suggests higher the economic freedom, lower the nuclear electric generation as expected. This model does not support the idea to cut the carbon dioxide emission via increasing nuclear share. The Hazard Model findings suggest that higher the load factor is, less likely the reactor will shut down. However, if it is still permanently closed downed, then this could be attributable to political hostility against nuclear power. There are also some projections indicating which reactors are most/least likely to be shut downed from the logit model. We also project which countries are most likely to increase/decrease their nuclear reliance from the residuals of EKC model.

A novel two-level dielectric barrier discharge reactor for methyl orange degradation.

PubMed

Tao, Xumei; Wang, Guowei; Huang, Liang; Ye, Qingguo; Xu, Dongyan

2016-12-15

A novel pilot two-level dielectric barrier discharge (DBD) reactor has been proposed and applied for degradation of continuous model wastewater. The two-level DBD reactor was skillfully realized with high space utilization efficiency and large contact area between plasma and wastewater. Various conditions such as applied voltage, initial concentration and initial pH value on methyl orange (MO) model wastewater degradation were investigated. The results showed that the appropriate applied voltage was 13.4 kV; low initial concentration and low initial pH value were conducive for MO degradation. The percentage removal of 4 L MO with concentration of 80 mg/L reached 94.1% after plasma treatment for 80min. Based on ultraviolet spectrum (UV), Infrared spectrum (IR), liquid chromatography-mass spectrometry (LC-MS) analysis of degradation intermediates and products, insights in the degradation pathway of MO were proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analysis of JKT01 Neutron Flux Detector Measurements In RSG-GAS Reactor Using LabVIEW

NASA Astrophysics Data System (ADS)

Rokhmadi; Nur Rachman, Agus; Sujarwono; Taryo, Taswanda; Sunaryo, Geni Rina

2018-02-01

The RSG-GAS Reactor, one of the Indonesia research reactors and located in Serpong, is owned by the National Nuclear Energy Agency (BATAN). The RSG-GAS reactor has operated since 1987 and some instrumentation and control systems are considered to be degraded and ageing. It is therefore, necessary to evaluate the safety of all instrumentation and controls and one of the component systems to be evaluated is the performance of JKT01 neutron flux detector. Neutron Flux Detector JKT01 basically detects neutron fluxes in the reactor core and converts it into electrical signals. The electrical signal is then forwarded to the amplifier (Amplifier) to become the input of the reactor protection system. One output of it is transferred to the Main Control Room (RKU) showing on the analog meter as an indicator used by the reactor operator. To simulate all of this matter, a program to simulate the output of the JKT01 Neutron Flux Detector using LabVIEW was developed. The simulated data is estimated using a lot of equations also formulated in LabVIEW. The calculation results are also displayed on the interface using LabVIEW available in the PC. By using this simulation program, it is successful to perform anomaly detection experiments on the JKT01 detector of RSG-GAS Reactor. The simulation results showed that the anomaly JKT01 neutron flux using electrical-current-base are respectively, 1.5×,1.7× and 2.0×.

Glow-to-arc transition in plasma-assisted combustion at 100 MPa

NASA Astrophysics Data System (ADS)

Larsson, A.; Andreasson, S.

2015-04-01

Electric energy can be added to the combustion of solid propellants in a gun in order to augment and to control parts of the internal ballistic cycle of the launch of a projectile. The pressure in the chamber and bore during launch is typically several hundred megapascal and the electric energy must be delivered to the flame at such a pressure level. To increase the understanding of the interaction between a flame and an electrical discharge at elevated pressure, experiments have been performed at 100 MPa in a combustion chamber where electric current has been conducted through the flame of a solid propellant. Pressure, voltage and current have been measured. The measured signals have been analysed and interpreted. The sequence of events has been interpreted as an initial formation of a glow-like discharge in the flame followed by a discharge mode transition to a filamentary arc discharge. The transition is shown to be dependent on the flame conductivity. For the test propellant used (Nzk5230 doped with 5% potassium nitrate), the flame conductivity is calculated to be 0.84 S m-1 and the discharge mode transition is found to occur after a dissipation of 0.2-0.4 kJ, or 11-22 kJ m-1 of electric energy, at an electric power of 0.1-0.5 MW.

POSITIONING MEANS FOR THE CONTROL ROD IN A NUCLEAR REACTOR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bell, F.R.

1963-09-26

An electric motor and transmission means for adjusting the position of the control rod in relation to the reactor core to control the level of activity in either sense and a lock that is retained in a locking condition by a longitudinal force derived electrically from the motor but arranged to be released when the electrical force is removed to allow the control rod in an emergency to drop into its shut-down position are described. (Gmelin Inst.)

A NEUTRONIC REACTOR

DOEpatents

Luebke, E.A.; Vandenberg, L.B.

1959-09-01

A nuclear reactor for producing thermoelectric power is described. The reactor core comprises a series of thermoelectric assemblies, each assembly including fissionable fuel as an active element to form a hot junction and a thermocouple. The assemblies are disposed parallel to each other to form spaces and means are included for Introducing an electrically conductive coolant between the assemblies to form cold junctions of the thermocouples. An electromotive force is developed across the entire series of the thermoelectric assemblies due to fission heat generated in the fuel causing a current to flow perpendicular to the flow of coolant and is distributed to a load outside of the reactor by means of bus bars electrically connected to the outermost thermoelectric assembly.

Multi-reactor power system configurations for multimegawatt nuclear electric propulsion

NASA Technical Reports Server (NTRS)

George, Jeffrey A.

1991-01-01

A modular, multi-reactor power system and vehicle configuration for piloted nuclear electric propulsion (NEP) missions to Mars is presented. Such a design could provide enhanced system and mission reliability, allowing a comfortable safety margin for early manned flights, and would allow a range of piloted and cargo missions to be performed with a single power system design. Early use of common power modules for cargo missions would also provide progressive flight experience and validation of standardized systems for use in later piloted applications. System and mission analysis are presented to compare single and multi-reactor configurations for piloted Mars missions. A conceptual design for the Hydra modular multi-reactor NEP vehicle is presented.

Preliminary Studies on Oleochemical Wastewater Treatment using Submerged Bed Biofilm Reactor (SBBR)

NASA Astrophysics Data System (ADS)

Ismail, Z.; Mahmood, N. A. N.; Ghafar, U. S. A.; Umor, N. A.; Muhammad, S. A. F.

2017-06-01

Wastewater discharge from the industry into water sources is one of the main reason for water pollution. The oleochemicals industry effluent produces high content of chemical oxygen demand (COD) with value between 6000-20,000 ppm. Effective treatment is required before wastewater effluent is discharged to environment. The aim of the study is to develop submerged bed biofilm reactor (SBBR) with packing materials in the cosmoball® carrier. Water quality such as chemical oxygen demands (COD), turbidity and pH were analysed. The result shows that the initial COD of 6000 ppm was reduced below 200 ppm. The optimum conditions for SBBR were obtained when green sponges used as packing material in cosmoball® effluent flowrate set at 100 mL/min; 1:1 ratio of cosmoball® volume to reactor volume and 1:1 ratio of active sludge (mixed culture) volume to reactor volume. Turbidity and pH were recorded with 9.0 NTU and 7.0 respectively, which indicated that SBBR is feasible as an alternative for conventional biological treatment in oleochemical industry.

Conversion of NO with a catalytic packed-bed dielectric barrier discharge reactor

NASA Astrophysics Data System (ADS)

Xu, CAO; Weixuan, ZHAO; Renxi, ZHANG; Huiqi, HOU; Shanping, CHEN; Ruina, ZHANG

2017-11-01

This paper discusses the conversion of nitric oxide (NO) with a low-temperature plasma induced by a catalytic packed-bed dielectric barrier discharge (DBD) reactor. Alumina oxide (Al2O3), glass (SiO2) and zirconium oxide (ZrO2), three different spherical packed materials of the same size, were each present in the DBD reactor. The NO conversion under varying input voltage and specific energy density, and the effects of catalysts (titanium dioxide (TiO2) and manganese oxide (MnO x ) coated on Al2O3) on NO conversion were investigated. The experimental results showed that NO conversion was greatly enhanced in the presence of packed materials in the reactor, and the catalytic packed bed of MnO x /Al2O3 showed better performance than that of TiO2/Al2O3. The surface and crystal structures of the materials and catalysts were characterized through scanning electron microscopy analysis. The final products were clearly observed by a Fourier transform infrared spectrometer and provided a better understanding of NO conversion.

Upward electrical discharges observed above Tropical Depression Dorian

PubMed Central

Liu, Ningyu; Spiva, Nicholas; Dwyer, Joseph R.; Rassoul, Hamid K.; Free, Dwayne; Cummer, Steven A.

2015-01-01

Observation of upward electrical discharges from thunderstorms has been sporadically reported in the scientific literature. According to their terminal altitudes, they are classified as starters (20–30 km), jets (40–50 km) and gigantic jets (70–90 km). They not only have a significant impact on the occupied atmospheric volumes but also electrically couple different atmospheric regions. However, as they are rare and unpredictable, our knowledge of them has been built on observations that typically record only one type of such discharges. Here we report a close-distance observation of seven upward discharges including one starter, two jets and four gigantic jets above Tropical Depression Dorian. Our optical and electromagnetic data indicate that all events are of negative polarity, suggesting they are initiated in the same thundercloud charge region. The data also indicate that the lightning-like discharge channel can extend above thunderclouds by about 30 km, but the discharge does not emit low-frequency electromagnetic radiation as normal lightning. PMID:25607345

Scaling of Dielectric Breakdown Thresholds in Earth's and CO2-rich atmospheres: Impact for Predictions of Extraterrestrial Transient Luminous Events and Lightning Discharges

NASA Astrophysics Data System (ADS)

Riousset, J. A.

2016-12-01

Earth's atmospheric electricity manifests itself in the form of glow, corona, streamer, and leader discharges observed as Saint Elmo's fire, sprites, lightning and jets discharges, and other Transient Luminous Events (TLEs). All of these are types of dielectric breakdown, but are governed by different physics. In particular, their initiation is associated with the crossing of specific electric field thresholds: relativistic runaway, streamer propagation, conventional breakdown, or thermal runaway thresholds, some better understood than others. For example, the initiation of a lightning discharge is known to occur when the local electric field exceeds a value similar to relativistic runaway field, but the exact threshold, as well as the physical mechanisms at work, remain rather unclear to date. Scaling laws for electric fields (and other quantities) have been established by Pasko et al. [GRL, 25(12), 2123-2126, 1998] and Pasko [NATO Sci. Series, Springer, 253-311, 2006]. In this work, we develop profiles for initiation criteria in air and in other atmospheric environments. We further calculate their associated scaling laws to determine the ability to trigger lightning flashes and TLEs in our solar system. This lets us predict the likelihood of electrical discharges on, e.g., Mars, Venus and Titan, and calculate the expected electric field conditions, under which discharges have been observed on Jupiter, Saturn, Uranus, and Neptune [Leblanc et al., ISSI Spa. Sci. Series, Springer, 2008, Yair, Adv. Space Res., 50(3), 293-310, 2012]. Our results anticipate the arrival of ExoMars 2016's Schiaparelli module, which will provide the first records of electric field at the surface of the planet [Déprez et al., EGU GA, 16, 16613, 2014]. This research is also motived by the increasing probability of manned missions to Mars and the potential electrostatic hazards it may face [Yair, 2012], and by the role of electrical discharges in the creation of active radicals, some of which may be of biological importance [Miller, Science, 117, 528-529, 1953; Biochem. Biophys. Acta, 23, 480-489, 1957].

Electron distribution functions in electric field environments

NASA Technical Reports Server (NTRS)

Rudolph, Terence H.

1991-01-01

The amount of current carried by an electric discharge in its early stages of growth is strongly dependent on its geometrical shape. Discharges with a large number of branches, each funnelling current to a common stem, tend to carry more current than those with fewer branches. The fractal character of typical discharges was simulated using stochastic models based on solutions of the Laplace equation. Extension of these models requires the use of electron distribution functions to describe the behavior of electrons in the undisturbed medium ahead of the discharge. These electrons, interacting with the electric field, determine the propagation of branches in the discharge and the way in which further branching occurs. The first phase in the extension of the referenced models , the calculation of simple electron distribution functions in an air/electric field medium, is discussed. Two techniques are investigated: (1) the solution of the Boltzmann equation in homogeneous, steady state environments, and (2) the use of Monte Carlo simulations. Distribution functions calculated from both techniques are illustrated. Advantages and disadvantages of each technique are discussed.

Overvoltage effect on electrical discharge type in medium-conductivity water in inhomogeneous pulsed electric field

NASA Astrophysics Data System (ADS)

Panov, V. A.; Vasilyak, L. M.; Pecherkin, V. Ya; Vetchinin, S. P.; Son, E. E.

2018-01-01

The transition between thermal and streamer discharges has been observed experimentally in water solution with conductivity 100 μS/cm applying positive voltage pulses to pin-to-rod electrodes. The transition happens at five-fold pulse amplitude. Considering streamer propagation as an ionization wave helped to establish relation between the parameters governing transition from one to another discharge mechanism.

Parts, Materials, and Processes Control Program for Expendable Launch Vehicles

DTIC Science & Technology

2015-07-31

burn-in, electrical tests (DWV, room and hot IR, partial discharge when in corona region); perform DPA with SEM/EDX analysis of dielectric...life test; x-ray and vicinal illumination inspection; electrical tests (DWV, room and hot IR, partial discharge when in corona region) Termination...defects; proper voltage derating. Partial discharge testing, corona inception testing up to 60% of rated voltage; CSAM screening; voltage burn

Discharge in Long Air Gaps; Modelling and applications

NASA Astrophysics Data System (ADS)

Beroual, A.; Fofana, I.

2016-06-01

Discharge in Long Air Gaps: Modelling and applications presents self-consistent predictive dynamic models of positive and negative discharges in long air gaps. Equivalent models are also derived to predict lightning parameters based on the similarities between long air gap discharges and lightning flashes. Macroscopic air gap discharge parameters are calculated to solve electrical, empirical and physical equations, and comparisons between computed and experimental results for various test configurations are presented and discussed. This book is intended to provide a fresh perspective by contributing an innovative approach to this research domain, and universities with programs in high-voltage engineering will find this volume to be a working example of how to introduce the basics of electric discharge phenomena.

Characterization of a joint recirculation of concentrated leachate and leachate to landfills with a microaerobic bioreactor for leachate treatment.

PubMed

He, Ruo; Wei, Xiao-Meng; Tian, Bao-Hu; Su, Yao; Lu, Yu-Lan

2015-12-01

With comparison of a traditional landfill, a joint recirculation of concentrated leachate and leachate to landfills with or without a microaerobic reactor for leachate treatment was investigated in this study. The results showed that the joint recirculation of concentrated leachate and leachate with a microaerobic reactor for leachate treatment could not only utilize the microaerobic reactor to buffer the fluctuation of quality and quantity of leachate during landfill stabilization, but also reduce the inhibitory effect of acidic pH and high concentrations of ammonium in recycled liquid on microorganisms and accelerate the degradation of landfilled waste. After 390 days of operation, the discharge of COD and total nitrogen (TN) from the landfill with leachate pretreatment by a microaerobic reactor was 7.4 and 0.9 g, respectively, which accounted for 0.7% and 2.6% of COD, 1.9% and 7.5% of the TN discharge from the landfills without recirculation and directly recirculated with leachate and concentrated leachate, respectively. The degradation of the organic matter and biodegradable matter (BDM) in the landfill reactors could fit well with the first-order kinetics. The highest degradation of the organic matter and BDM was observed in the joint recirculation system with a microaerobic reactor for leachate treatment with the degradation constant of the first-order kinetics of 0.001 and 0.002. Copyright © 2015 Elsevier Ltd. All rights reserved.

Plasma promoted manufacturing of hydrogen and vehicular applications

NASA Astrophysics Data System (ADS)

Bromberg, Leslie

2003-10-01

Plasmas can be used for promoting reformation of fuels. Plasma-based reformers developed at MIT use a low temperature, low power, low current electrical discharge to promote partial oxidation conversion of hydrocarbon fuels into hydrogen and CO. The very fuel rich mixture is hard to ignite, and the plasmatron provides a volume-ignition. To minimize erosion and to simplify the power supply, a low current high voltage discharge is used, with wide area electrodes. The plasmatron fuel reformer operates at or slightly above atmospheric pressure. The plasma-based reformer technology provides the advantages of rapid startup and transient response; efficient conversion of the fuel to hydrogen rich gas; compact size; relaxation or elimination of reformer catalyst requirements; and capability to process difficult to reform fuels. These advantages enable use of hydrogen-manufacturing reformation technology in cars using available fuels, such as gasoline and diesel. This plasma-based reformer technology can provide substantial throughputs even without the use of a catalyst. The electrical power consumption of the device is minimized by design and operational characteristics (less than 500 W peak and 200 W average). The product from these plasma reactors is a hydrogen rich mixture that can be used for combustion enhancement and emissions aftertreatment in vehicular applications. By converting a small fraction of the fuel to hydrogen rich gas, in-cylinder combustion can be improved. With minor modification of the engine, use of hydrogen rich gas results in increased fuel efficiency and decreased emissions of smog producing gases. The status of plasma based reformer technology and its application to vehicles will be described.

Observation of the inductive to helicon mode transition in a weakly magnetized solenoidal inductive discharge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Min-Hyong; Chung, Chin-Wook

2008-10-13

A mode transition from an inductive mode to a helicon mode is observed in a solenoidal inductive discharge immersed in a weak dc magnetic field. The measured electron temperature and the plasma density at the reactor radial boundary show a sudden increase when the magnetic field strength reaches the critical value and the electron cyclotron frequency exceeds the rf driving frequency. These increases are due to the electron heating by the helicon wave. Such increases in the temperature and the density are not observed at the plasma center because the helicon wave cannot propagate to the center of the solenoidalmore » type reactor unless the magnetic field is very high. These results show that the transition of the discharge from the inductive to the helicon mode occurs at the critical magnetic field strength.« less

Electric organ discharges and near-field spatiotemporal patterns of the electromotive force in a sympatric assemblage of Neotropical electric knifefish.

PubMed

Waddell, Joseph C; Rodríguez-Cattáneo, Alejo; Caputi, Angel A; Crampton, William G R

2016-10-01

Descriptions of the head-to-tail electric organ discharge (ht-EOD) waveform - typically recorded with electrodes at a distance of approximately 1-2 body lengths from the center of the subject - have traditionally been used to characterize species diversity in gymnotiform electric fish. However, even taxa with relatively simple ht-EODs show spatiotemporally complex fields near the body surface that are determined by site-specific electrogenic properties of the electric organ and electric filtering properties of adjacent tissues and skin. In Brachyhypopomus, a pulse-discharging genus in the family Hypopomidae, the regional characteristics of the electric organ and the role that the complex 'near field' plays in communication and/or electrolocation are not well known. Here we describe, compare, and discuss the functional significance of diversity in the ht-EOD waveforms and near-field spatiotemporal patterns of the electromotive force (emf-EODs) among a species-rich sympatric community of Brachyhypopomus from the upper Amazon. Copyright © 2016 Elsevier Ltd. All rights reserved.

Role of electric discharges in the generation of atmospheric vortices

NASA Astrophysics Data System (ADS)

Sinkevich, O. A.; Maslov, S. A.; Gusein-zade, N. G.

2017-02-01

The existing thermohydrodynamic and hydroelectromagnetic models of tornado are considered. The potentialities of the humid atmosphere as a heat engine generating air vortices are analyzed in detail. The ability of long-term atmospheric electric discharges to form a tornado funnel and create an initial twist of up to 10-3-10-2 s-1 in it are estimated. The possible effect of a lightning discharge on the initiation and evolution of the tornado is discussed. It is shown that the electric current flowing along the lightning channel can lead to helical instability and generation of a weak primary vortex. The channel formed in the atmosphere by a lightning discharge and the vortex motion of the parent thundercloud can enhance the primary vortex and promote its transformation into a tornado. Possible mechanisms of enhancement of the primary vortex created by a lightning discharge and the possibility of its transformation into a tornado in the postdischarge stage are discussed.

Post-breakdown secondary discharges at the electrode/dielectric interface of a cylindrical barrier discharge

NASA Astrophysics Data System (ADS)

Carman, Robert; Ward, Barry; Kane, Deborah

2011-10-01

The electrical breakdown characteristics of a double-walled cylindrical dielectric barrier discharge (DBD) lamp with a neon buffer gas under pulsed voltage excitation have been investigated. Following the formation of plasma in the main discharge gap, we have observed secondary breakdown phenomena at the inner and outer mesh electrode/dielectric interfaces under specific operating conditions. Plasma formation at these interfaces is investigated by monitoring the Ozone production rate in controlled flows of ultra high purity oxygen together with the overall electrical voltage-charge characteristics of the lamp. The results show that this secondary breakdown only occurs after the main discharge plasma has been established, and that significant electrical power may be dissipated in generating these spurious secondary plasmas. The results are important with regards to optimising the design and identifying efficient operating regimes of DBD based devices that employ mesh-type or wire/strip electrodes.

Measurements of Electric Field in a Nanosecond Pulse Discharge by 4-WAVE Mixing

NASA Astrophysics Data System (ADS)

Baratte, Edmond; Adamovich, Igor V.; Simeni Simeni, Marien; Frederickson, Kraig

2017-06-01

Picosecond four-wave mixing is used to measure temporally and Picosecond four-wave mixing is used to measure temporally and spatially resolved electric field in a nanosecond pulse dielectric discharge sustained in room air and in an atmospheric pressure hydrogen diffusion flame. Measurements of the electric field, and more precisely the reduced electric field (E/N) in the plasma is critical for determination rate coefficients of electron impact processes in the plasma, as well as for quantifying energy partition in the electric discharge among different molecular energy modes. The four-wave mixing measurements are performed using a collinear phase matching geometry, with nitrogen used as the probe species, at temporal resolution of about 2 ns . Absolute calibration is performed by measurement of a known electrostatic electric field. In the present experiments, the discharge is sustained between two stainless steel plate electrodes, each placed in a quartz sleeve, which greatly improves plasma uniformity. Our previous measurements of electric field in a nanosecond pulse dielectric barrier discharge by picosecond 4-wave mixing have been done in air at room temperature, in a discharge sustained between a razor edge high-voltage electrode and a plane grounded electrode (a quartz plate or a layer of distilled water). Electric field measurements in a flame, which is a high-temperature environment, are more challenging because the four-wave mixing signal is proportional to the to square root of the difference betwen the populations of N2 ground vibrational level (v=0) and first excited vibrational level (v=1). At high temperatures, the total number density is reduced, thus reducing absolute vibrational level populations of N2. Also, the signal is reduced further due to a wider distribution of N2 molecules over multiple rotational levels at higher temperatures, while the present four-wave mixing diagnostics is using spectrally narrow output of a ps laser and a high-pressure Raman cell, providing access only to a few N2 rotational levels. Because of this, the four-wave mixing signal in the flame is lower by more than an order of magnitude compared to the signal generated in room temperature air plasma. Preliminary experiments demonstrated four-wave mixing signal generated by the electric field in the flame, following ns pulse discharge breakdown. The electric field in the flame is estimated using four-wave mixing signal calibration vs. temperature in electrostatic electric field generated in heated air. Further measurements in the flame are underway.

One-Dimensional Modeling Studies of the Gaseous Electronics Conference RF Reference Cell

PubMed Central

Govindan, T. R.; Meyyappan, M.

1995-01-01

A review of the one-dimensional modeling studies in the literature of the Gaseous Electronics Conference (GEC) reference plasma reactor is presented. Most of the studies are based on the fluid model description of the discharge and some utilize hybrid fluid-kinetic schemes. Both models are discussed here briefly. The models provide a basic understanding of the discharge mechanisms and reproduce several critical discharge features observed experimentally. PMID:29151755

Enhanced treatment efficiency of an anaerobic sequencing batch reactor (ASBR) for cassava stillage with high solids content.

PubMed

Luo, Gang; Xie, Li; Zhou, Qi

2009-06-01

Cassava stillage is a high strength organic wastewater with high suspended solids (SS) content. The efficiency of cassava stillage treatment using an anaerobic sequencing batch reactor (ASBR) was significantly enhanced by discharging settled sludge to maintain a lower sludge concentration (about 30 g/L) in the reactor. Three hydraulic retention times (HRTs), namely 10 d, 7.5 d, 5 d, were evaluated at this condition. The study demonstrated that at an HRT of 5 d and an organic loading rate (OLR) of 11.3 kg COD/(m(3) d), the total chemical oxygen demand (TCOD) and soluble COD (SCOD) removal efficiency can still be maintained at above 80%. The settleability of digested cassava stillage was improved significantly, and thus only a small amount of settled sludge needed to be discharged to maintain the sludge concentration in the reactor. Furthermore, the performance of ASBR operated at low and high sludge concentration (about 79.5 g/L without sludge discharged) was evaluated at an HRT of 5 d. The TCOD removal efficiency and SS in the effluent were 61% and 21.9 g/L respectively at high sludge concentration, while the values were 85.1% and 2.4 g/L at low sludge concentration. Therefore, low sludge concentration is recommended for ASBR treating cassava stillage at an HRT 5 d due to lower TCOD and SS in the effluent, which could facilitate post-treatment.

Capacitor discharge process for welding braided cable

DOEpatents

Wilson, Rick D.

1995-01-01

A capacitor discharge process for welding a braided cable formed from a plurality of individual cable strands to a solid metallic electrically conductive member comprises the steps of: (a) preparing the electrically conductive member for welding by bevelling one of its end portions while leaving an ignition projection extending outwardly from the apex of the bevel; (b) clamping the electrically conductive member in a cathode fixture; (c) connecting the electrically conductive member clamped in the cathode fixture to a capacitor bank capable of being charged to a preselected voltage value; (d) preparing the braided cable for welding by wrapping one of its end portions with a metallic sheet to form a retaining ring operable to maintain the individual strands of the braided cable in fixed position within the retaining ring; (e) clamping the braided cable and the retaining ring as a unit in an anode fixture so that the wrapped end portion of the braided cable faces the ignition projection of the electrically conductive member; and (f) moving the cathode fixture towards the anode fixture until the ignition projection of the electrically conductive member contacts the end portion of the braided cable thereby allowing the capacitor bank to discharge through the electrically conductive member and through the braided cable and causing the electrically conductive member to be welded to the braided cable via capacitor discharge action.

Summary of NR Program Prometheus Efforts

DOE Office of Scientific and Technical Information (OSTI.GOV)

J Ashcroft; C Eshelman

2006-02-08

The Naval Reactors Program led work on the development of a reactor plant system for the Prometheus space reactor program. The work centered on a 200 kWe electric reactor plant with a 15-20 year mission applicable to nuclear electric propulsion (NEP). After a review of all reactor and energy conversion alternatives, a direct gas Brayton reactor plant was selected for further development. The work performed subsequent to this selection included preliminary nuclear reactor and reactor plant design, development of instrumentation and control techniques, modeling reactor plant operational features, development and testing of core and plant material options, and development ofmore » an overall project plan. Prior to restructuring of the program, substantial progress had been made on defining reference plant operating conditions, defining reactor mechanical, thermal and nuclear performance, understanding the capabilities and uncertainties provided by material alternatives, and planning non-nuclear and nuclear system testing. The mission requirements for the envisioned NEP missions cannot be accommodated with existing reactor technologies. Therefore concurrent design, development and testing would be needed to deliver a functional reactor system. Fuel and material performance beyond the current state of the art is needed. There is very little national infrastructure available for fast reactor nuclear testing and associated materials development and testing. Surface mission requirements may be different enough to warrant different reactor design approaches and development of a generic multi-purpose reactor requires substantial sacrifice in performance capability for each mission.« less

Electrical equivalent circuit for microstrip micro-plasma: control of EM propagation and numerical simulations.

PubMed

Mohamad, Almustafa; Tân-Hoa, Vuong; Jacques, David

2012-01-01

An approach to determine an equivalent electrical circuit of a micro planar discharge on a microstrip printed circuit is reported. The micro discharge is used to realize a dynamic microwave switching circuit. This approach is based on the measurement of the discharge current and the transmission coefficient for a given frequency 2.45 GHz. Numerical methods like FEM can be used to study the effect of plasma parameters on the propagation of electromagnetic waves through a microstrip printed circuit. Plasma behaves as flexible elements that can change its electrical proprieties such as conductivity.

Prebreakdown characteristics of weakly ionized liquid and gaseous media in the strongly nonuniform electric field

NASA Astrophysics Data System (ADS)

Apfelbaum, M. S.; Syrovatka, R. A.; Vladimirov, V. I.

2018-01-01

A theoretical model of electrohydrodynamic prebreakdown phenomena in slightly ionized (weakly conductive) media is proposed. The electric high voltage conduction of weakly conductive liquids and slightly ionized gases in intense electric fields using this model is considered. The formula for the calculations of volt-ampere characteristics under high voltage spherical capacitor field is analytically obtained. The experimental corona discharge volt-ampere characteristics of air are presented. It was found that the size of the ionization region in the case of corona discharge in air increases monotonically with increasing discharge voltage.

Inductive gas line for pulsed lasers

DOEpatents

Benett, William J.; Alger, Terry W.

1985-01-01

A gas laser having a metal inlet gas feed line assembly shaped as a coil, to function as an electrical inductance and therefore high impedance to pulses of electric current applied to electrodes at opposite ends of a discharge tube of a laser, for example. This eliminates a discharge path for the laser through the inlet gas feed line. A ferrite core extends through the coil to increase the inductance of the coil and provide better electric isolation. By elimination of any discharge breakdown through the gas supply, efficiency is increased and a significantly longer operating lifetime of the laser is provided.

Inductive gas line for pulsed lasers

DOEpatents

Benett, W.J.; Alger, T.W.

1982-09-29

A gas laser having a metal inlet gas feed line assembly shaped as a coil, to function as an electrical inductance and therefore high impedance to pulses of electric current applied to electrodes at opposite ends of a discharge tube of a laser, for example. This eliminates a discharge path for the laser through the inlet gas feed line. A ferrite core extends through the coil to increase the inductance of the coil and provide better electric isolation. By elimination of any discharge breakdown through the gas supply, efficiency is increased and a significantly longer operating lifetime of the laser is provided.

Exploration to generate atmospheric pressure glow discharge plasma in air

NASA Astrophysics Data System (ADS)

Wenzheng, LIU; Chuanlong, MA; Shuai, ZHAO; Xiaozhong, CHEN; Tahan, WANG; Luxiang, ZHAO; Zhiyi, LI; Jiangqi, NIU; Liying, ZHU; Maolin, CHAI

2018-03-01

Atmospheric pressure glow discharge (APGD) plasma in air has high application value. In this paper, the methods of generating APGD plasma in air are discussed, and the characteristics of dielectric barrier discharge (DBD) in non-uniform electric field are studied. It makes sure that APGD in air is formed by DBD in alternating current electric field with using the absorbing electron capacity of electret materials to provide initial electrons and to end the discharge progress. Through designing electric field to form two-dimensional space varying electric field and three-dimensional space varying electric field, the development of electron avalanches in air-gap is suppressed effectively and a large space of APGD plasma in air is generated. Further, through combining electrode structures, a large area of APGD plasma in air is generated. On the other hand, by using the method of increasing the density of initial electrons, millimeter-gap glow discharge in atmospheric pressure air is formed, and a maximum gap distance between electrodes is 8 mm. By using the APGD plasma surface treatment device composed of contact electrodes, the surface modification of high polymer materials such as aramid fiber and polyester are studied and good effect of modifications is obtained. The present paper provides references for the researchers of industrial applications of plasma.

Partial Discharge Characteristics of Polymer Nanocomposite Materials in Electrical Insulation: A Review of Sample Preparation Techniques, Analysis Methods, Potential Applications, and Future Trends

PubMed Central

Izzati, Wan Akmal; Adzis, Zuraimy; Shafanizam, Mohd

2014-01-01

Polymer nanocomposites have recently been attracting attention among researchers in electrical insulating applications from energy storage to power delivery. However, partial discharge has always been a predecessor to major faults and problems in this field. In addition, there is a lot more to explore, as neither the partial discharge characteristic in nanocomposites nor their electrical properties are clearly understood. By adding a small amount of weight percentage (wt%) of nanofillers, the physical, mechanical, and electrical properties of polymers can be greatly enhanced. For instance, nanofillers in nanocomposites such as silica (SiO2), alumina (Al2O3) and titania (TiO2) play a big role in providing a good approach to increasing the dielectric breakdown strength and partial discharge resistance of nanocomposites. Such polymer nanocomposites will be reviewed thoroughly in this paper, with the different experimental and analytical techniques used in previous studies. This paper also provides an academic review about partial discharge in polymer nanocomposites used as electrical insulating material from previous research, covering aspects of preparation, characteristics of the nanocomposite based on experimental works, application in power systems, methods and techniques of experiment and analysis, and future trends. PMID:24558326

Anticipating electrical breakdown in dielectric elastomer actuators

NASA Astrophysics Data System (ADS)

Muffoletto, Daniel P.; Burke, Kevin M.; Zirnheld, Jennifer L.

2013-04-01

The output strain of a dielectric elastomer actuator is directly proportional to the square of its applied electric field. However, since the likelihood of electric breakdown is elevated with an increased applied field, the maximum operating electric field of the dielectric elastomer is significantly derated in systems employing these actuators so that failure due to breakdown remains unlikely even as the material ages. In an effort to ascertain the dielectric strength so that stronger electric fields can be applied, partial discharge testing is used to assess the health of the actuator by detecting the charge that is released when localized instances of breakdown partially bridge the insulator. Pre-stretched and unstretched samples of VHB4910 tape were submerged in dielectric oil to remove external sources of partial discharges during testing, and the partial discharge patterns were recorded just before failure of the dielectric sample.

OH radicals generated by DC corona discharge for improving the pulsed discharge desulfuration efficiency.

PubMed

Li, Jie; Li, Guo-feng; Wu, Yan; Wang, Ning-hui; Huang, Qiu-nan

2004-01-01

Positive DC corona discharge is formed with needle-plate electrode configuration, in which the water vapor is ejected though the needle points. The purpose is to increase the numbers of the water-based radicals, ionize the water molecule and improve the desulfuration efficiency of pulsed corona reactor. The water ions were determined by four stages molecular beam mass spectrometer and diagnose the water-based radicals by emission spectrograph. A conclusion on formation of ions and radicals with DC corona discharges can be drawn.

Applicability of 100kWe-class of space reactor power systems to NASA manned space station missions

NASA Technical Reports Server (NTRS)

Silverman, S. W.; Willenberg, H. J.; Robertson, C.

1985-01-01

An assessment is made of a manned space station operating with sufficiently high power demands to require a multihundred kilowatt range electrical power system. The nuclear reactor is a competitor for supplying this power level. Load levels were selected at 150kWe and 300kWe. Interactions among the reactor electrical power system, the manned space station, the space transportation system, and the mission were evaluated. The reactor shield and the conversion equipment were assumed to be in different positions with respect to the station; on board, tethered, and on a free flyer platform. Mission analyses showed that the free flyer concept resulted in unacceptable costs and technical problems. The tethered reactor providing power to an electrolyzer for regenerative fuel cells on the space station, results in a minimum weight shield and can be designed to release the reactor power section so that it moves to a high altitude orbit where the decay period is at least 300 years. Placing the reactor on the station, on a structural boom is an attractive design, but heavier than the long tethered reactor design because of the shield weight for manned activity near the reactor.

ELECTRICAL LINES ARRIVE FROM CENTRAL FACILITIES AREA, SOUTH OF MTR. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ELECTRICAL LINES ARRIVE FROM CENTRAL FACILITIES AREA, SOUTH OF MTR. EXCAVATION RUBBLE IN FOREGROUND. CONTRACTOR CRAFT SHOPS, CRANES, AND OTHER MATERIALS ON SITE. CAMERA FACES EAST, WITH LITTLE BUTTE AND MIDDLE BUTTE IN DISTANCE. INL NEGATIVE NO. 335. Unknown Photographer, 7/1/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Nuclear power: the bargain we can't afford

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morgan, R.

1977-01-01

This is a handbook for citizens who wish to raise questions about the costs of atomic energy. It explains, step-by-step, why nuclear reactors have failed to produce low-cost electricity, and it tells citizens how they can use economic arguments to challenge nuclear expansion. Part One, The Costs of Nuclear Energy, contains 7 chapters--The Price of Power (electricity is big business); Mushrooming Capital Costs (nuclear construction costs are skyrocketing); Nuclear Lemons (reactors spend much of their time closed for repairs); The Faulty Fuel Cycle (turning uranium into electricity is not as simple as the utilities say); Hidden Costs (goverment subsidies obscuremore » the true costs of atomic energy); Ratepayer Roulette (nuclear problems translate into higher electric rates); and Alternatives to the Atom (coal-fired power and energy conservation can meet future energy needs more cheaply than nuclear energy). Part Two, Challenging Nuclear Power, contains 3 chapters--Regulators and Reactors (state utility commissions can eliminate the power companies' bias toward nuclear energy); Legislation, Licensing, and Lawsuits (nuclear critics can challenge reactor construction in numerous forums); and Winning the Battle (building an organization is a crucial step in fighting nuclear power). (MCW)« less

A cost/benefit analysis of commercial fusion-fission hybrid reactor development

NASA Astrophysics Data System (ADS)

Kostoff, Ronald N.

1983-04-01

A simple algorithm was developed that allows rapid computation of the ratio, R, of present worth of benefits to present worth of hybrid R&D program costs as a function of potential hybrid unit electricity cost savings, discount rate, electricity demand growth rate, total hybrid R&D program cost, and time to complete a demonstration reactor. In the sensitivity study, these variables were assigned nominal values (unit electricity cost savings of 4 mills/kW-hr, discount rate of 4%/year, growth rate of 2.25%/year, total R&D program cost of 20 billion, and time to complete a demonstration reactor of 30 years), and the variable of interest was varied about its nominal value. Results show that R increases with decreasing discount rate and increasing unit electricity savings and ranges from 4 to 94 as discount rate ranges from 5 to 3%/year and unit electricity savings range from 2 to 6 mills/kW-hr. R increases with increasing growth rate and ranges from 3 to 187 as growth rate ranges from 1 to 3.5%/year and unit electricity cost savings range from 2 to 6 mills/kW-hr. R attains a maximum value when plotted against time to complete a demonstration reactor. The location of this maximum value occurs at shorter completion times as discount rate increases, and this optimal completion time ranges from 20 years for a discount rate of 4%/year to 45 years for a discount rate of 3%/year.

Nanoelectronics and Plasma Processing---The Next 15 Years and Beyond

NASA Astrophysics Data System (ADS)

Lieberman, Michael A.

2006-10-01

The number of transistors per chip has doubled every 2 years since 1959, and this doubling will continue over the next 15 years as transistor sizes shrink. There has been a 25 million-fold decrease in cost for the same performance, and in 15 years a desktop computer will be hundreds of times more powerful than one today. Transistors now have 37 nm (120 atoms) gate lengths and 1.5 nm (5 atoms) gate oxide thicknesses. The smallest working transistor has a 5 nm (17 atoms) gate length, close to the limiting gate length, from simulations, of about 4 nm. Plasma discharges are used to fabricate hundreds of billions of these nano-size transistors on a silicon wafer. These discharges have evolved from a first generation of ``low density'' reactors capacitively driven by a single source, to a second generation of ``high density'' reactors (inductive and electron cyclotron resonance) having two rf power sources, in order to control independently the ion flux and ion bombarding energy to the substrate. A third generation of ``moderate density'' reactors, driven capacitively by one high and one low frequency rf source, is now widely used. Recently, triple frequency and combined dc/dual frequency discharges have been investigated, to further control processing characteristics, such as ion energy distributions, uniformity, and plasma etch selectivities. There are many interesting physics issues associated with these discharges, including stochastic heating of discharge electrons by dual frequency sheaths, nonlinear frequency interactions, powers supplied by the multi-frequency sources, and electromagnetic effects such as standing waves and skin effects. Beyond the 4 nm transistor limit lies a decade of further performance improvements for conventional nanoelectronics, and beyond that, a dimly-seen future of spintronics, single-electron transistors, cross-bar latches, and molecular electronics.

40 CFR 61.64 - Emission standard for polyvinyl chloride plants.

Code of Federal Regulations, 2012 CFR

2012-07-01

... was taken to prevent the discharge, and measures adopted to prevent future discharges. (b) Stripper. The concentration of vinly chloride in each exhaust gas stream from each stripper is not to exceed 10... precedes the stripper (or the reactor if the plant has no stripper) in the plant process flow is not to...

40 CFR 61.64 - Emission standard for polyvinyl chloride plants.

Code of Federal Regulations, 2014 CFR

2014-07-01

... was taken to prevent the discharge, and measures adopted to prevent future discharges. (b) Stripper. The concentration of vinly chloride in each exhaust gas stream from each stripper is not to exceed 10... precedes the stripper (or the reactor if the plant has no stripper) in the plant process flow is not to...

40 CFR 61.64 - Emission standard for polyvinyl chloride plants.

Code of Federal Regulations, 2013 CFR

2013-07-01

... was taken to prevent the discharge, and measures adopted to prevent future discharges. (b) Stripper. The concentration of vinly chloride in each exhaust gas stream from each stripper is not to exceed 10... precedes the stripper (or the reactor if the plant has no stripper) in the plant process flow is not to...

Electric organ discharge diversification in mormyrid weakly electric fish is associated with differential expression of voltage-gated ion channel genes.

PubMed

Nagel, Rebecca; Kirschbaum, Frank; Tiedemann, Ralph

2017-03-01

In mormyrid weakly electric fish, the electric organ discharge (EOD) is used for species recognition, orientation and prey localization. Produced in the muscle-derived adult electric organ, the EOD exhibits a wide diversity across species in both waveform and duration. While certain defining EOD characteristics can be linked to anatomical features of the electric organ, many factors underlying EOD differentiation are yet unknown. Here, we report the differential expression of 13 Kv1 voltage-gated potassium channel genes, two inwardly rectifying potassium channel genes, two previously studied sodium channel genes and an ATPase pump in two sympatric species of the genus Campylomormyrus in both the adult electric organ and skeletal muscle. Campylomormyrus compressirostris displays a basal EOD, largely unchanged during development, while C. tshokwe has an elongated, putatively derived discharge. We report an upregulation in all Kv1 genes in the electric organ of Campylomormyrus tshokwe when compared to both skeletal muscle and C. compressirostris electric organ. This pattern of upregulation in a species with a derived EOD form suggests that voltage-gated potassium channels are potentially involved in the diversification of the EOD signal among mormyrid weakly electric fish.

Microinstability properties of negative magnetic shear discharges in the Tokamak Fusion Test Reactor and DIII-D

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rewoldt, G.; Tang, W.M.; Lao, L.L.

1997-03-01

The microinstability properties of discharges with negative (reversed) magnetic shear in the Tokamak Fusion Test Reactor (TFTR) and DIII-D experiments with and without confinement transitions are investigated. A comprehensive kinetic linear eigenmode calculation employing the ballooning representation is employed with experimentally measured profile data, and using the corresponding numerically computed magnetohydrodynamic (MHD) equilibria. The instability considered is the toroidal drift mode (trapped-electron-{eta}{sub i} mode). A variety of physical effects associated with differing q-profiles are explained. In addition, different negative magnetic shear discharges at different times in the discharge for TFTR and DIII-D are analyzed. The effects of sheared toroidal rotation,more » using data from direct spectroscopic measurements for carbon, are analyzed using comparisons with results from a two-dimensional calculation. Comparisons are also made for nonlinear stabilization associated with shear in E{sub r}/RB{sub {theta}}. The relative importance of changes in different profiles (density, temperature, q, rotation, etc.) on the linear growth rates is considered.« less

60th Anniversary of electricity production from light water reactors: Historical review of the contribution of materials science to the safety of the pressure vessel

NASA Astrophysics Data System (ADS)

van Duysen, J. C.; Meric de Bellefon, G.

2017-02-01

The first light water nuclear reactor dedicated to electricity production was commissioned in Shippingport, Pennsylvania in the United States in 1957. Sixty years after the event, it is clear that this type of reactor will be a major source of electricity and one of the key solutions to limit climate change in the 21st century. This article pays homage to the teams that contributed to this achievement by their involvement in research and development and their determination to push back the frontiers of knowledge. Via a few examples of scientific or technological milestones, it describes the evolution of ideas, models, and techniques during the last 60 years, and gives the current state-of-the-art in areas related to the safety of the reactor pressure vessel. Among other topics, it focuses on vessel manufacturing, steel fracture mechanics analysis, and understanding of irradiation-induced damage.

Effect of reactor coolant radioactivity upon configuration feasibility for a nuclear electric propulsion vehicle

NASA Technical Reports Server (NTRS)

Soffer, L.; Wright, G. N.

1973-01-01

A preliminary shielding analysis was carried out for a conceptual nuclear electric propulsion vehicle designed to transport payloads from low earth orbit to synchronous orbit. The vehicle employed a thermionic nuclear reactor operating at 1575 kilowatts and generated 120 kilowatts of electricity for a round-trip mission time of 2000 hours. Propulsion was via axially directed ion engines employing 3300 pounds of mercury as a propellant. The vehicle configuration permitted a reactor shadow shield geometry using LiH and the mercury propellant for shielding. However, much of the radioactive NaK reactor coolant was unshielded and in close proximity to the power conditioning electronics. An estimate of the radioactivity of the NaK coolant was made and its unshielded dose rate to the power conditioning equipment calculated. It was found that the activated NaK contributed about three-fourths of the gamma dose constraint. The NaK dose was considered a sufficiently high fraction of the allowable gamma dose to necessitate modifications in configuration.

Carbon Coating Of Copper By Arc-Discharge Pyrolysis

NASA Technical Reports Server (NTRS)

Ebihara, Ben T.; Jopek, Stanley

1988-01-01

Adherent, abrasion-resistant coat deposited with existing equipment. Carbon formed and deposited as coating on copper substrate by pyrolysis of hydrocarbon oil in electrical-arc discharges. Technique for producing carbon deposits on copper accomplished with electrical-discharge-machining equipment used for cutting metals. Applications for new coating technique include the following: solar-energy-collecting devices, coating of metals other than copper with carbon, and carburization of metal surfaces.

Photo-triggering and secondary electron produced ionization in electric discharge ArF* excimer lasers

NASA Astrophysics Data System (ADS)

Xiong, Zhongmin; Kushner, Mark J.

2011-10-01

Electric discharge excimer lasers are sustained in multi-atmosphere attaching gas mixtures that are typically preionized to enable a reproducible, uniform glow, which maximizes optical quality and gain. This preionization is often accomplished using UV light produced by a corona discharge within the plasma cavity. To quantify the relationship between corona discharge properties and those of the laser discharge, the triggering of electron avalanche by preionizing UV light in an electric discharge-pumped ArF* excimer laser was numerically investigated using a two-dimensional model. The preionizing UV fluxes were generated by a corona-bar discharge driven by the same voltage pulse as the main discharge sustained in a multi-atmospheric Ne/Ar/Xe/F2 gas mixture. The resulting peak photo-electron density in the inter-electrode spacing is around 108 cm-3, and its distribution is biased toward the UV source. The preionization density increases with increasing dielectric constant and capacitance of the corona bar. The symmetry and uniformity of the discharge are, however, improved significantly once the main avalanche develops. In addition to bulk electron impact ionization, the ionization generated by sheath accelerated secondary electrons was found to be important in sustaining the discharge current at experimentally observed values. At peak current, the magnitude of the ionization by sheath accelerated electrons is comparable to that from bulk electron impact in the vicinity of the cathode.

22. A sideview of the rear face of a typical ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. A side-view of the rear face of a typical pile, in this case the F Reactor in February 1945. The low railing and walkway are part of the discharge elevator. Notice the vertical row of numbers on the right that identified the rows of process tubes. D-8326 - B Reactor, Richland, Benton County, WA

Passive cooling system for nuclear reactor containment structure

DOEpatents

Gou, Perng-Fei; Wade, Gentry E.

1989-01-01

A passive cooling system for the contaminant structure of a nuclear reactor plant providing protection against overpressure within the containment attributable to inadvertent leakage or rupture of the system components. The cooling system utilizes natural convection for transferring heat imbalances and enables the discharge of irradiation free thermal energy to the atmosphere for heat disposal from the system.

Multiplex electric discharge gas laser system

NASA Technical Reports Server (NTRS)

Laudenslager, James B. (Inventor); Pacala, Thomas J. (Inventor)

1987-01-01

A multiple pulse electric discharge gas laser system is described in which a plurality of pulsed electric discharge gas lasers are supported in a common housing. Each laser is supplied with excitation pulses from a separate power supply. A controller, which may be a microprocessor, is connected to each power supply for controlling the application of excitation pulses to each laser so that the lasers can be fired simultaneously or in any desired sequence. The output light beams from the individual lasers may be combined or utilized independently, depending on the desired application. The individual lasers may include multiple pairs of discharge electrodes with a separate power supply connected across each electrode pair so that multiple light output beams can be generated from a single laser tube and combined or utilized separately.

Customized electric power storage device for inclusion in a microgrid

DOEpatents

Goldsmith, Steven Y.; Wilson, David; Robinett, III, Rush D.

2017-08-01

An electric power storage device included in a microgrid is described herein. The electric power storage device has at least one of a charge rate, a discharge rate, or a power retention capacity that has been customized for the microgrid. The at least one of the charge rate, the discharge rate, or the power retention capacity of the electric power storage device is computed based at least in part upon specified power source parameters in the microgrid and specified load parameters in the microgrid.

Critical analysis of partial discharge dynamics in air filled spherical voids

NASA Astrophysics Data System (ADS)

Callender, G.; Golosnoy, I. O.; Rapisarda, P.; Lewin, P. L.

2018-03-01

In this paper partial discharge (PD) is investigated inside a spherical air filled void at atmospheric pressure using a drift diffusion model. Discharge dynamics consisted of an electron avalanche transitioning into positive streamer, in agreement with earlier work on dielectric barrier discharges. Different model configurations were utilised to test many of the concepts employed in semi-analytical PD activity models, which use simplistic descriptions of the discharge dynamics. The results showed that many of these concepts may be erroneous, with significant discrepancies between the canonical reasoning and the simulation results. For example, the residual electric field, the electric field after a discharge, is significantly lower than the estimates used by classical PD activity models in the literature.

Application of Simulated Reactivity Feedback in Nonnuclear Testing of a Direct-Drive Gas-Cooled Reactor

NASA Technical Reports Server (NTRS)

Bragg-Sitton, S. M.; Webster, K. L.

2007-01-01

Nonnuclear testing can be a valuable tool in the development of an in-space nuclear power or propulsion system. In a nonnuclear test facility, electric heaters are used to simulate heat from nuclear fuel. Standard testing allows one to fully assess thermal, heat transfer, and stress related attributes of a given system but fails to demonstrate the dynamic response that would be present in an integrated, fueled reactor system. The integration of thermal hydraulic hardware tests with simulated neutronic response provides a bridge between electrically heated testing and full nuclear testing. By implementing a neutronic response model to simulate the dynamic response that would be expected in a fueled reactor system, one can better understand system integration issues, characterize integrated system response times and response and response characteristics, and assess potential design improvements with a relatively small fiscal investment. Initial system dynamic response testing was demonstrated on the integrated SAFE 100a heat pipe cooled, electrically heated reactor and heat exchanger hardware. This Technical Memorandum discusses the status of the planned dynamic test methodology for implementation in the direct-drive gas-cooled reactor testing and assesses the additional instrumentation needed to implement high-fidelity dynamic testing.

Nighttime observations of thunderstorm electrical activity from a high altitude airplane

NASA Technical Reports Server (NTRS)

Brook, M.; Vonnegut, B.; Orville, R. E.; Vaughan, O. H., Jr.

1984-01-01

Nocturnal thunderstorms were observed from above and features of cloud structure and lightning which are not generally visible from the ground are discussed. Most, lightning activity seems to be associated with clouds with strong convective cauliflower tops. In both of the storms lightning channels were visible in the clear air above the cloud. It is shown that substances produced by thunderstorm electrical discharges can be introduced directly into the stratosphere. The cause and nature of the discharges above the cloud are not clear. They may be produced by accumulations of space charge in the clear air above the cloud. The discharges may arise solely because of the intense electric fields produced by charges within the cloud. In the latter case the ions introduced by these discharges will increase the electrical conductivity of the air above the cloud and increase the conduction current that flows from the cloud to the electrosphere. More quantitative data at higher resolution may show significant spectral differences between cloud to ground and intracloud strokes. It is shown that electric field change data taken with an electric field change meter mounted in an airplane provide data on lightning discharges from above that are quite similar to those obtained from the ground in the past. The optical signals from dart leaders, from return strokes, and from continuing currents are recognizable, can be used to provide information on the fine structure of lightning, and can be used to distinguish between cloud to ground and intracloud flashes.

The component content of active particles in a plasma-chemical reactor based on volume barrier discharge

NASA Astrophysics Data System (ADS)

Soloshenko, I. A.; Tsiolko, V. V.; Pogulay, S. S.; Terent'yeva, A. G.; Bazhenov, V. Yu; Shchedrin, A. I.; Ryabtsev, A. V.; Kuzmichev, A. I.

2007-02-01

In this paper the results of theoretical and experimental studies of the component content of active particles formed in a plasma-chemical reactor composed of a multiple-cell generator of active particles, based on volume barrier discharge, and a working chamber are presented. For calculation of the content of uncharged plasma components an approach is proposed which is based on averaging of the power introduced over the entire volume. Advantages of such an approach lie in an absence of fitting parameters, such as the dimensions of microdischarges, their surface density and rate of breakdown. The calculation and the experiment were accomplished with the use of dry air (20% relative humidity) as the plasma generating medium. Concentrations of O3, HNO3, HNO2, N2 O5 and NO3 were measured experimentally in the discharge volume and working chamber for the residence time of particles on a discharge of 0.3 s and more and discharge specific power of 1.5 W cm-3. It has been determined that the best agreement between the calculation and the experiment occurs at calculated gas medium temperatures in the discharge plasma of about 400-425 K, which correspond to the experimentally measured rotational temperature of nitrogen. In most cases the calculated concentrations of O3, HNO3, HNO2, N2O5 and NO3 for the barrier discharge and the working chamber are in fairly good agreement with the respective measured values.

Charging of moving surfaces by corona discharges sustained in air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jun-Chieh, E-mail: junchwan@umich.edu; Kushner, Mark J., E-mail: mjkush@umich.edu; Zhang, Daihua, E-mail: dhzhang@tju.edu.cn

Atmospheric pressure corona discharges are used in electrophotographic (EP) printing technologies for charging imaging surfaces such as photoconductors. A typical corona discharge consists of a wire (or wire array) biased with a few hundred volts of dc plus a few kV of ac voltage. An electric discharge is produced around the corona wire from which electrons drift towards and charge the underlying dielectric surface. The surface charging reduces the voltage drop across the gap between the corona wire and the dielectric surface, which then terminates the discharge, as in a dielectric barrier discharge. In printing applications, this underlying surface ismore » continuously moving throughout the charging process. For example, previously charged surfaces, which had reduced the local electric field and terminated the local discharge, are translated out of the field of view and are replaced with uncharged surface. The uncharged surface produces a rebound in the electric field in the vicinity of the corona wire which in turn results in re-ignition of the discharge. The discharge, so reignited, is then asymmetric. We found that in the idealized corona charging system we investigated, a negatively dc biased corona blade with a dielectric covered ground electrode, the discharge is initially sustained by electron impact ionization from the bulk plasma and then dominated by ionization from sheath accelerated secondary electrons. Depending on the speed of the underlying surface, the periodic re-ignition of the discharge can produce an oscillatory charging pattern on the moving surface.« less

Dynamic Response Testing in an Electrically Heated Reactor Test Facility

NASA Astrophysics Data System (ADS)

Bragg-Sitton, Shannon M.; Morton, T. J.

2006-01-01

Non-nuclear testing can be a valuable tool in the development of a space nuclear power or propulsion system. In a non-nuclear test bed, electric heaters are used to simulate the heat from nuclear fuel. Standard testing allows one to fully assess thermal, heat transfer, and stress related attributes of a given system, but fails to demonstrate the dynamic response that would be present in an integrated, fueled reactor system. The integration of thermal hydraulic hardware tests with simulated neutronic response provides a bridge between electrically heated testing and fueled nuclear testing. By implementing a neutronic response model to simulate the dynamic response that would be expected in a fueled reactor system, one can better understand system integration issues, characterize integrated system response times and response characteristics, and assess potential design improvements at a relatively small fiscal investment. Initial system dynamic response testing was demonstrated on the integrated SAFE-100a heat pipe (HP) cooled, electrically heated reactor and heat exchanger hardware, utilizing a one-group solution to the point kinetics equations to simulate the expected neutronic response of the system. Reactivity feedback calculations were then based on a bulk reactivity feedback coefficient and measured average core temperature. This paper presents preliminary results from similar dynamic testing of a direct drive gas cooled reactor system (DDG), demonstrating the applicability of the testing methodology to any reactor type and demonstrating the variation in system response characteristics in different reactor concepts. Although the HP and DDG designs both utilize a fast spectrum reactor, the method of cooling the reactor differs significantly, leading to a variable system response that can be demonstrated and assessed in a non-nuclear test facility. Planned system upgrades to allow implementation of higher fidelity dynamic testing are also discussed. Proposed DDG testing will utilize a higher fidelity point kinetics model to control core power transients, and reactivity feedback will be based on localized feedback coefficients and several independent temperature measurements taken within the core block. This paper presents preliminary test results and discusses the methodology that will be implemented in follow-on DDG testing and the additional instrumentation required to implement high fidelity dynamic testing.

Development of a Polysilicon Process Based on Chemical Vapor Deposition of Dichlorosilane in an Advanced Siemen's Reactor

NASA Technical Reports Server (NTRS)

Arevidson, A. N.; Sawyer, D. H.; Muller, D. M.

1983-01-01

Dichlorosilane (DCS) was used as the feedstock for an advanced decomposition reactor for silicon production. The advanced reactor had a cool bell jar wall temperature, 300 C, when compared to Siemen's reactors previously used for DCS decomposition. Previous reactors had bell jar wall temperatures of approximately 750 C. The cooler wall temperature allows higher DCS flow rates and concentrations. A silicon deposition rate of 2.28 gm/hr-cm was achieved with power consumption of 59 kWh/kg. Interpretation of data suggests that a 2.8 gm/hr-cm deposition rate is possible. Screening of lower cost materials of construction was done as a separate program segment. Stainless Steel (304 and 316), Hastalloy B, Monel 400 and 1010-Carbon Steel were placed individually in an experimental scale reactor. Silicon was deposited from trichlorosilane feedstock. The resultant silicon was analyzed for electrically active and metallic impurities as well as carbon. No material contributed significant amounts of electrically active or metallic impurities, but all contributed carbon.

46 CFR 111.30-29 - Emergency switchboards.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... regulator unit acting on the exciter field, each emergency switchboard must have: (1) A generator field rheostat; (2) A double pole field switch; (3) Discharge clips; and (4) A discharge resistor. (g) Each...

46 CFR 111.30-29 - Emergency switchboards.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... regulator unit acting on the exciter field, each emergency switchboard must have: (1) A generator field rheostat; (2) A double pole field switch; (3) Discharge clips; and (4) A discharge resistor. (g) Each...

Experimental investigation on electrical characteristics and dose measurement of dielectric barrier discharge plasma device used for therapeutic application

NASA Astrophysics Data System (ADS)

Shahbazi Rad, Zahra; Abbasi Davani, Fereydoun

2017-04-01

In this research, a Dielectric Barrier Discharge (DBD) plasma device operating in air has been made. The electrical characteristics of this device like instantaneous power, dissipated power, and discharge capacitance have been measured. Also, the effects of applied voltage on the dissipated power and discharge capacitance of the device have been investigated. The determination of electrical parameters is important in DBD plasma device used in living tissue treatment for choosing the proper treatment doses and preventing the destructive effects. The non-thermal atmospheric pressure DBD plasma source was applied for studying the acceleration of blood coagulation time, in vitro and wound healing time, in vivo. The citrated blood drops coagulated within 5 s treatment time by DBD plasma. The effects of plasma temperature and electric field on blood coagulation have been studied as an affirmation of the applicability of the constructed device. Also, the effect of constructed DBD plasma on wound healing acceleration has been investigated.

Experimental investigation on electrical characteristics and dose measurement of dielectric barrier discharge plasma device used for therapeutic application.

PubMed

Shahbazi Rad, Zahra; Abbasi Davani, Fereydoun

2017-04-01

In this research, a Dielectric Barrier Discharge (DBD) plasma device operating in air has been made. The electrical characteristics of this device like instantaneous power, dissipated power, and discharge capacitance have been measured. Also, the effects of applied voltage on the dissipated power and discharge capacitance of the device have been investigated. The determination of electrical parameters is important in DBD plasma device used in living tissue treatment for choosing the proper treatment doses and preventing the destructive effects. The non-thermal atmospheric pressure DBD plasma source was applied for studying the acceleration of blood coagulation time, in vitro and wound healing time, in vivo. The citrated blood drops coagulated within 5 s treatment time by DBD plasma. The effects of plasma temperature and electric field on blood coagulation have been studied as an affirmation of the applicability of the constructed device. Also, the effect of constructed DBD plasma on wound healing acceleration has been investigated.

Air-jet power ultrasonic field applied to electrical discharge

NASA Astrophysics Data System (ADS)

Balek, Rudolf; Pekarek, Stanislav

2010-01-01

We describe a new setup of the Hartmann air-jet ultrasonic generator combined with electrical discharge in the nozzle-resonator gap. Using the schlieren visualization of air jet and ultrasonic field we investigated the shape and structure of the discharge and we determined relationship among the acoustic field in the nozzle-resonator gap, generator ultrasonic emission and discharge behavior. Apart of the fact that the discharge in the nozzle-resonator gap is stabilized and becomes more uniform, it increases its volume when the generator works in the regime of ultrasonic emission. At the same time the discharge light emission distribution is more over uniform in the gap. In the regime without the ultrasonic emission the discharge light emission is fragmented. We also found that the impedance of the discharge is decreased in case when the generator works in the regime of ultrasonic emission.

Nifekalant hydrochloride suppresses severe electrical storm in patients with malignant ventricular tachyarrhythmias.

PubMed

Washizuka, Takashi; Chinushi, Masaomi; Watanabe, Hiroshi; Hosaka, Yukio; Komura, Satoru; Sugiura, Hirotaka; Hirono, Takashi; Furushima, Hiroshi; Tanabe, Yasutaka; Aizawa, Yoshifusa

2005-12-01

Some patients with an implantable cardioverter-defibrillator (ICD) suffer from burst of inappropriate multiple discharges (severe electrical storm), and because the current therapeutic options are limited, the effect of nifekalant hydrochloride, a new class III drug, on severe electrical storm was investigated in the present study. Ninety-one consecutive patients treated with ICD were included in the study (M 70; mean age 58 years; left ventricular ejection fraction 45+/-15%). Severe electrical storm was defined as more than 10 ICD discharges within 1 h. During a mean follow-up period of 30+/-13 months, 41/91 (45%) patients had appropriate ICD therapy for arrhythmias and severe electrical storm occurred in 11 of them (12%) at 20+/-18 months after ICD implantation. The mean number of ICD discharges/h during severe electrical storm was 18+/-12. In 4 of 10 patients, severe electrical storm was successfully suppressed by a combination of deep sedation and beta-blocking agent; 6 other patients were refractory to this treatment, but severe electrical storm was successfully suppressed by intravenous administration of nifekalant hydrochloride with no adverse effects. Nifekalant hydrochloride is an effective and safe treatment for severe electrical storm.

Preferential vibrational excitation in microwave nitrogen plasma assessed by Raman scattering

NASA Astrophysics Data System (ADS)

Gatti, N.; Ponduri, S.; Peeters, F. J. J.; van den Bekerom, D. C. M.; Minea, T.; Tosi, P.; van de Sanden, M. C. M.; van Rooij, G. J.

2018-05-01

Vibrational activation of N2 molecules in a flowing microwave plasma is investigated in the context of utilising electrical energy for chemical conversion. Spatial profiles of rotational (T r ) and vibrational (T v ) temperatures are measured by Raman scattering. Maximum values of T r = 3500 K and T v = 6000 K were observed in the centre of the plasma at low pressure (50 mbar). A detailed quantification of the local energy content shows how the strong non-equilibrium character of low pressure discharges compares with a closer-to-equilibrium energy distribution at higher pressures. Measurements performed downstream of the plasma display the ability of the microwave flowing reactor to deliver up to 48% of the specific energy input (SEI) into internal degrees of freedom of the gas molecules. Specifically, 23% of the SEI is loaded into the vibrational mode, which is potentially available to enhance chemical reactivity of endothermic reactions.

Effects of gas temperature on NO(x) removal by dielectric barrier discharge.

PubMed

Wang, Tao; Sun, Bao-Min; Xiao, Hai-Ping

2013-01-01

The purpose of this investigation is to discuss the effect of gas temperature on NO(x) removal by dielectric barrier discharge. The Boltzmann equation was used to analyse the electron distribution function in the reactor, and experiments were conducted to find out the effects of different temperatures. The calculation results show that, with a rise in the temperature, E/N increases, increasing the ionization rate. When the ratio of electric field strength to total gas density (E/N) rises from 50 to 150 Td, the ionization rate and electron mean energy increase by 2.0 x 10(5) and 2.3, respectively. The experiments show that in the NO/N2 system, when the temperature increases to 1 30 degrees C and the applied voltage is 11.1 kV, the discharge power is 44.7 W, which is higher than the discharge power of 35.4 W found at 25 degrees C; in the NO/O2/N2 system, an increase in the temperature increases the decomposition of active O3 species, producing a negative effect on NO oxidation; in the NO/O2/N2/C2H4 system, when the temperature increases, the quantity of active species HO2 increases and the NO removal reaction rate increases, reflecting an obvious improvement in the NO removal; and in the NO/O2/N2/C2H4/H2O system, at 25 degrees C, 90 degrees C, and 130 degrees C, when the energy density is 239.7 J L(-1), the NO removal efficiencies are 52.8%, 66.4%, and 71.0%, respectively.

Nuclear Energy Policy

DTIC Science & Technology

2009-12-10

Small Modular Reactors Rising cost estimates for large conventional nuclear power plants—widely projected to be $6 billion or more—have contributed to growing interest in proposals for smaller, modular reactors. Ranging from about 40 to 350 megawatts of electrical capacity, such reactors would be only a fraction of the size of current commercial reactors. Several modular reactors would be installed together to make up a power block with a single control room, under most concepts. Modular reactor concepts would use a variety of technologies,

Particle based plasma simulation for an ion engine discharge chamber

NASA Astrophysics Data System (ADS)

Mahalingam, Sudhakar

Design of the next generation of ion engines can benefit from detailed computer simulations of the plasma in the discharge chamber. In this work a complete particle based approach has been taken to model the discharge chamber plasma. This is the first time that simplifying continuum assumptions on the particle motion have not been made in a discharge chamber model. Because of the long mean free paths of the particles in the discharge chamber continuum models are questionable. The PIC-MCC model developed in this work tracks following particles: neutrals, singly charged ions, doubly charged ions, secondary electrons, and primary electrons. The trajectories of these particles are determined using the Newton-Lorentz's equation of motion including the effects of magnetic and electric fields. Particle collisions are determined using an MCC statistical technique. A large number of collision processes and particle wall interactions are included in the model. The magnetic fields produced by the permanent magnets are determined using Maxwell's equations. The electric fields are determined using an approximate input electric field coupled with a dynamic determination of the electric fields caused by the charged particles. In this work inclusion of the dynamic electric field calculation is made possible by using an inflated plasma permittivity value in the Poisson solver. This allows dynamic electric field calculation with minimal computational requirements in terms of both computer memory and run time. In addition, a number of other numerical procedures such as parallel processing have been implemented to shorten the computational time. The primary results are those modeling the discharge chamber of NASA's NSTAR ion engine at its full operating power. Convergence of numerical results such as total number of particles inside the discharge chamber, average energy of the plasma particles, discharge current, beam current and beam efficiency are obtained. Steady state results for the particle number density distributions and particle loss rates to the walls are presented. Comparisons of numerical results with experimental measurements such as currents and the particle number density distributions are made. Results from a parametric study and from an alternative magnetic field design are also given.

Phosphoric acid as an electrolyte additive for lead/acid batteries in electric-vehicle applications

NASA Astrophysics Data System (ADS)

Meissner, E.

The influence of the addition of phosphoric acid to the electrolyte on the performance of gelled lead/acid electric-vehiicle batteries is investigated. This additive reduces the reversible capacity decay of the positive electrode significantly which is observed upon extended cycling when recharge of the battery is performed at low initial rate. This is important when low-rate on-board chargers are used. Pulsed discharge, typical for electric-vehicle application, induces reversible capacity decay more than constant-current discharge at a same depth-of-discharge, as well with as without the addition of phosphoric acid. By contrast, hindrance in presence of H 3PO 4 for both the recharge and the discharge reaction helps to homogenize the state of many individual cells during cycling in long battery strings. Reversible capacity loss, which occurs after extended cycling and when pulsed discharge is applied, can be recovered by a single discharge at very low rate with batteries with and without the addition of phosphoric acid. The discharge-rate dependency of the capacity is significantly reduced when phosphoric acid is added. The pulse discharge behaviour may be better, even if the nominal capacity is reduced. The experimental findings of the influence of phosphoric acid addition is discussed in terms of the aggregate-of-spheres model of reversible capacity decay.

An experimental system for controlled exposure of biological samples to electrostatic discharges.

PubMed

Marjanovič, Igor; Kotnik, Tadej

2013-12-01

Electrostatic discharges occur naturally as lightning strokes, and artificially in light sources and in materials processing. When an electrostatic discharge interacts with living matter, the basic physical effects can be accompanied by biophysical and biochemical phenomena, including cell excitation, electroporation, and electrofusion. To study these phenomena, we developed an experimental system that provides easy sample insertion and removal, protection from airborne particles, observability during the experiment, accurate discharge origin positioning, discharge delivery into the sample either through an electric arc with adjustable air gap width or through direct contact, and reliable electrical insulation where required. We tested the system by assessing irreversible electroporation of Escherichia coli bacteria (15 mm discharge arc, 100 A peak current, 0.1 μs zero-to-peak time, 0.2 μs peak-to-halving time), and gene electrotransfer into CHO cells (7 mm discharge arc, 14 A peak current, 0.5 μs zero-to-peak time, 1.0 μs peak-to-halving time). Exposures to natural lightning stroke can also be studied with this system, as due to radial current dissipation, the conditions achieved by a stroke at a particular distance from its entry are also achieved by an artificial discharge with electric current downscaled in magnitude, but similar in time course, correspondingly closer to its entry. © 2013.

Discharge current distribution in stratified soil under impulse discharge

NASA Astrophysics Data System (ADS)

Eniola Fajingbesi, Fawwaz; Shahida Midi, Nur; Elsheikh, Elsheikh M. A.; Hajar Yusoff, Siti

2017-06-01

The mobility of charge particles traversing a material defines its electrical properties. Soil (earth) have long been the universal grounding before and after the inception of active ground systems for electrical appliance purpose due to it semi-conductive properties. The soil can thus be modelled as a single material exhibiting semi-complex inductive-reactive impedance. Under impulse discharge such as lightning strikes to soil this property of soil could result in electric potential level fluctuation ranging from ground potential rise/fall to electromagnetic pulse coupling that could ultimately fail connected electrical appliance. In this work we have experimentally model the soil and lightning discharge using point to plane electrode setup to observe the current distribution characteristics at different soil conductivity [mS/m] range. The result presented from this research indicate above 5% shift in conductivity before and after discharge which is significant for consideration when dealing with grounding designs. The current distribution in soil have also be successfully observed and analysed from experimental result using mean current magnitude in relation to electrode distance and location, current density variation with depth all showing strong correlation with theoretical assumptions of a semi-complex impedance material.

ETR BUILDING, TRA642, INTERIOR. FIRST FLOOR. REACTOR IS IN CENTER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR BUILDING, TRA-642, INTERIOR. FIRST FLOOR. REACTOR IS IN CENTER OF VIEW. CAMERA FACES NORTHWEST. NOTE CRANE RAILS AND DANGLING ELECTRICAL CABLE AT UPPER PART OF VIEW FOR "MOFFETT 2 TON" CRANE. INL NEGATIVE NO. HD46-14-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

148. ARAIII Reactor building (ARA608) Floor plan. Shows location of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

148. ARA-III Reactor building (ARA-608) Floor plan. Shows location of reactor, heater, and mechanical loop pits; mechanical and electrical equipment rooms; and other work areas. Aerojet-general 880-area/GCRE-608-A-1. Date: February 1958. Ineel index code no. 063-0608-00-013-102612. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

Moderation of neoclassical impurity accumulation in high temperature plasmas of helical devices

NASA Astrophysics Data System (ADS)

Velasco, J. L.; Calvo, I.; Satake, S.; Alonso, A.; Nunami, M.; Yokoyama, M.; Sato, M.; Estrada, T.; Fontdecaba, J. M.; Liniers, M.; McCarthy, K. J.; Medina, F.; Van Milligen, B. Ph; Ochando, M.; Parra, F.; Sugama, H.; Zhezhera, A.; The LHD Experimental Team; The TJ-II Team

2017-01-01

Achieving impurity and helium ash control is a crucial issue in the path towards fusion-grade magnetic confinement devices, and this is particularly the case of helical reactors, whose low-collisionality ion-root operation scenarios usually display a negative radial electric field which is expected to cause inwards impurity pinch. In this work we discuss, based on experimental measurements and standard predictions of neoclassical theory, how plasmas of very low ion collisionality, similar to those observed in the impurity hole of the large helical device (Yoshinuma et al and The LHD Experimental Group 2009 Nucl. Fusion 49 062002, Ida et al and The LHD Experimental Group 2009 Phys. Plasmas 16 056111 and Yokoyama et al and LHD Experimental Group 2002 Nucl. Fusion 42 143), can be an exception to this general rule, and how a negative radial electric field can coexist with an outward impurity flux. This interpretation is supported by comparison with documented discharges available in the International Stellarator-Heliotron Profile Database, and it can be extrapolated to show that achievement of high ion temperature in the core of helical devices is not fundamentally incompatible with low core impurity content.

ALARA Council: Sharing our resources and experiences to reduce doses at Commonwealth Edison Facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rescek, F.

1995-03-01

Commonwealth Edison Company is an investor-owned utility company supplying electricity to over three million customers (eight million people) in Chicago and northern Illinois, USA. The company operates 16 generating stations which have the capacity to produce 22,522 megawatts of electricity. Six of these generating stations, containing 12 nuclear units, supply 51% of this capacity. The 12 nuclear units are comprised of four General Electric boiling water (BWR-3) reactors, two General Electric BWR-5 reactors, and six Westinghouse four-loop pressurized water reactors (PWR). In August 1993, Commonwealth Edison created an ALARA Council with the responsibility to provide leadership and guidance that resultsmore » in an effective ALARA Culture within the Nuclear Operations Division. Unlike its predecessor, the Corporate ALARA Committee, the ALARA Council is designed to bring together senior managers from the six nuclear stations and corporate to create a collaborative effort to reduce occupational doses at Commonwealth Edison`s stations.« less

30 CFR 7.64 - Technical requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... voltage that can be applied across an electric contact that discharges a capacitor shall not be greater...) Capacitor discharge. The blasting unit shall include an automatic means to dissipate any electric charge remaining in any capacitor after the blasting unit is deenergized and not in use. (j) Construction. Blasting...

30 CFR 7.64 - Technical requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... voltage that can be applied across an electric contact that discharges a capacitor shall not be greater...) Capacitor discharge. The blasting unit shall include an automatic means to dissipate any electric charge remaining in any capacitor after the blasting unit is deenergized and not in use. (j) Construction. Blasting...

30 CFR 7.64 - Technical requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... voltage that can be applied across an electric contact that discharges a capacitor shall not be greater...) Capacitor discharge. The blasting unit shall include an automatic means to dissipate any electric charge remaining in any capacitor after the blasting unit is deenergized and not in use. (j) Construction. Blasting...

Electric oxygen-iodine laser discharge scaling and laser performance

NASA Astrophysics Data System (ADS)

Woodard, Brian S.

In 2004, a research partnership between the University of Illinois and CU Aerospace demonstrated the first electric discharge pumped oxygen-iodine laser referred to as ElectricOIL. This exciting improvement over the standard oxygen-iodine laser utilizes a gas discharge to produce the necessary electronically-excited molecular oxygen, O2(a 1Delta), that serves as the energy reservoir in the laser system. Pumped by a near-resonant energy transfer, the atomic iodine lases on the I(2P1/2) → I(2P3/2) transition at 1315 nm. Molecular oxygen diluted with helium and a small fraction of nitric oxide flows through a radiofrequency discharge where O2(a 1Delta) and many other excited species are created. Careful investigations to understand the benefits and problems associated with these other states in the laser system allowed this team to succeed where other research groups had failed, and after the initial demonstration, the ElectricOIL research focus shifted to increasing the efficiencies along with the output laser energy. Among other factors, the laser power scales with the flow rate of oxygen in the desired excited state. Therefore, high yields of O2(a 1Delta) are desired along with high input oxygen flow rates. In the early ElectricOIL experiments, the pressure in the discharge was approximately 10 Torr, but increased flow rates forced the pressure to between 50 and 60 Torr requiring a number of new discharge designs in order to produce similar yields of O2(a1Delta) efficiently. Experiments were conducted with only the electric discharge portion of the laser system using emission diagnostics to study the effects of changing the discharge geometry, flow residence time, and diluent. The power carried by O2(a 1Delta) is the maximum power that could be extracted from the laser, and the results from these studies showed approximately 2500 W stored in the O2(a1Delta) state. Transferring this energy into the atomic iodine has been another challenge in ElectricOIL as experiments have shown that the iodine is pumped into the excited state slower than is predicted by the known kinetics, resulting in reduced output power. An elementary model is presented that may partially explain this problem. Larger laser resonator volumes are employed to improve power extraction by providing more flow time for iodine pumping. The results presented in this work in conjunction with the efforts of others led to ElectricOIL scaling from 200 mW in the initial demonstration to nearly 500 W.

Nuclear power propulsion system for spacecraft

NASA Astrophysics Data System (ADS)

Koroteev, A. S.; Oshev, Yu. A.; Popov, S. A.; Karevsky, A. V.; Solodukhin, A. Ye.; Zakharenkov, L. E.; Semenkin, A. V.

2015-12-01

The proposed designs of high-power space tugs that utilize solar or nuclear energy to power an electric jet engine are reviewed. The conceptual design of a nuclear power propulsion system (NPPS) is described; its structural diagram, gas circuit, and electric diagram are discussed. The NPPS incorporates a nuclear reactor, a thermal-to-electric energy conversion system, a system for the conversion and distribution of electric energy, and an electric propulsion system. Two criterion parameters were chosen in the considered NPPS design: the temperature of gaseous working medium at the nuclear reactor outlet and the rotor speed of turboalternators. The maintenance of these parameters at a given level guarantees that the needed electric voltage is generated and allows for power mode control. The processes of startup/shutdown and increasing/reducing the power, the principles of distribution of electric energy over loads, and the probable emergencies for the proposed NPPS design are discussed.

Reliability and safety of the electrical power supply complex of the Hanford production reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robbins, F.D.

Safety has been and must continue to be the inviolable modulus by which the operation of a nuclear reactor must be judged. A malfunction in any reactor may well result in a release of fission products which may dissipate over a wide geographical area. Such dissipation may place the health, happiness and even the lives of the people in the region in serious jeopardy. As a result, the property damage and liability cost may reach astronomical values in the order of magnitude of billions of dollars. Reliability of the electrical network is an indispensable factor in attaining a high ordermore » of safety assurance. Progress in the peaceful use of atomic energy may take the form of electrical power generation using the nuclear reactor as a source of thermal energy. In view of these factors it seems appropriate and profitable that a critical engineering study be made of the safety and reliability of the Hanford reactors without regard to cost economics. This individual and independent technical engineering analysis was made without regard to Hanford traditional engineering and administration assignments. The main objective has been to focus attention on areas which seem to merit further detailed study on conditions which seem to need adjustment but most of all on those changes which will improve reactor safety. This report is the result of such a study.« less

New reactor technology: safety improvements in nuclear power systems.

PubMed

Corradini, M L

2007-11-01

Almost 450 nuclear power plants are currently operating throughout the world and supplying about 17% of the world's electricity. These plants perform safely, reliably, and have no free-release of byproducts to the environment. Given the current rate of growth in electricity demand and the ever growing concerns for the environment, nuclear power can only satisfy the need for electricity and other energy-intensive products if it can demonstrate (1) enhanced safety and system reliability, (2) minimal environmental impact via sustainable system designs, and (3) competitive economics. The U.S. Department of Energy with the international community has begun research on the next generation of nuclear energy systems that can be made available to the market by 2030 or earlier, and that can offer significant advances toward these challenging goals; in particular, six candidate reactor system designs have been identified. These future nuclear power systems will require advances in materials, reactor physics, as well as thermal-hydraulics to realize their full potential. However, all of these designs must demonstrate enhanced safety above and beyond current light water reactor systems if the next generation of nuclear power plants is to grow in number far beyond the current population. This paper reviews the advanced Generation-IV reactor systems and the key safety phenomena that must be considered to guarantee that enhanced safety can be assured in future nuclear reactor systems.

Parameters for Fabricating Nano-Au Colloids through the Electric Spark Discharge Method with Micro-Electrical Discharge Machining.

PubMed

Tseng, Kuo-Hsiung; Chung, Meng-Yun; Chang, Chaur-Yang

2017-06-02

In this study, the Electric Spark Discharge Method (ESDM) was employed with micro-electrical discharge machining (m-EDM) to create an electric arc that melted two electrodes in deionized water (DW) and fabricated nano-Au colloids through pulse discharges with a controlled on-off duration (T ON -T OFF ) and a total fabrication time of 1 min. A total of six on-off settings were tested under normal experimental conditions and without the addition of any chemical substances. Ultraviolet-visible spectroscopy (UV-Vis), Zetasizer Nano measurements, and scanning electron microscopy-energy dispersive X-ray (SEM-EDX) analyses suggested that the nano-Au colloid fabricated at 10-10 µs (10 µs on, 10 µs off) had higher concentration and suspension stability than products made at other T ON -T OFF settings. The surface plasmon resonance (SPR) of the colloid was 549 nm on the first day of fabrication and stabilized at 532 nm on the third day. As the T ON -T OFF period increased, the absorbance (i.e., concentration) of all nano-Au colloids decreased. Absorbance was highest at 10-10 µs. The SPR peaks stabilized at 532 nm across all T ON -T OFF periods. The Zeta potential at 10-10 µs was -36.6 mV, indicating that no nano-Au agglomeration occurred and that the particles had high suspension stability.

Parameters for Fabricating Nano-Au Colloids through the Electric Spark Discharge Method with Micro-Electrical Discharge Machining

PubMed Central

Tseng, Kuo-Hsiung; Chung, Meng-Yun; Chang, Chaur-Yang

2017-01-01

In this study, the Electric Spark Discharge Method (ESDM) was employed with micro-electrical discharge machining (m-EDM) to create an electric arc that melted two electrodes in deionized water (DW) and fabricated nano-Au colloids through pulse discharges with a controlled on–off duration (TON–TOFF) and a total fabrication time of 1 min. A total of six on–off settings were tested under normal experimental conditions and without the addition of any chemical substances. Ultraviolet–visible spectroscopy (UV–Vis), Zetasizer Nano measurements, and scanning electron microscopy–energy dispersive X-ray (SEM–EDX) analyses suggested that the nano-Au colloid fabricated at 10–10 µs (10 µs on, 10 µs off) had higher concentration and suspension stability than products made at other TON–TOFF settings. The surface plasmon resonance (SPR) of the colloid was 549 nm on the first day of fabrication and stabilized at 532 nm on the third day. As the TON–TOFF period increased, the absorbance (i.e., concentration) of all nano-Au colloids decreased. Absorbance was highest at 10–10 µs. The SPR peaks stabilized at 532 nm across all TON–TOFF periods. The Zeta potential at 10–10 µs was −36.6 mV, indicating that no nano-Au agglomeration occurred and that the particles had high suspension stability. PMID:28574476

Method of operating a neutronic reactor

DOEpatents

Woods, Wallace K.

1976-05-25

1. A method of operating a reactor having an active portion of a given length between a charging end and a discharging end, a first end region of the reactor extending from the charging end for one-quarter to one-third of said given length, a second end region extending from the discharging end for one-quarter to one-third of said given length, and a middle region extending between said end regions, said method comprising the steps of inserting end to end in the active region through the charging end a first group of bodies filling the middle region and a second group of bodies filling the first end region, irradiating the first and second groups of bodies while in the middle and first end regions, removing the first group from the reactor through the second end region, shifting the second group through the middle region to the second end region, inserting new first and second groups of bodies through the charging face into the middle and first end regions of the reactor, respectively, and irradiating the original second group and the new first and second groups while in the second end, middle, and first end regions, respectively, removing the original second group and the new first group from the reactor through the second end region, shifting the new second group through the middle region to the second end region, and irradiating the new second group again, whereby the first groups of bodies are irradiated only once and the second groups are irradiated twice.

Electric discharge in water as a source of UV radiation, ozone and hydrogen peroxide

NASA Astrophysics Data System (ADS)

Anpilov, A. M.; Barkhudarov, E. M.; Bark, Yu B.; Zadiraka, Yu V.; Christofi, M.; Kozlov, Yu N.; Kossyi, I. A.; Kop'ev, V. A.; Silakov, V. P.; Taktakishvili, M. I.; Temchin, S. M.

2001-03-01

Results are presented from investigations of multispark electric discharge in water excited along multielectrode metal-dielectric systems with gas supply into the interelectrode gaps. The intensity distribution of discharge radiation in the region covering the biologically active soft UV (190≤λ≤430 nm) has been determined and the absolute number of quanta in this wavelength interval has been measured. The potentiality of the slipping surface discharge in water for its disinfection is analysed. The energy expenditure for water cleansing is estimated to be as low as ~10-4 kWh l-1.

Field strengths and dissipated powers in microwave-excited high-pressure sulphur discharges

NASA Astrophysics Data System (ADS)

van Dongen, Menno; Körber, Achim; van der Heijden, Harm; Jonkers, Jeroen; Scholl, Robert; van der Mullen, Joost

1998-11-01

A method which makes it is possible to measure the electric field strength in microwave discharges is presented. A condition for this method is that the plasma has such a low conductivity that the associated skin depth is larger than the discharge radius. It is found that the field strength in high-pressure sulphur lamps is around 400 V 0022-3727/31/21/015/img10. Furthermore, this method allows the determination of the power absorbed in the resonator's wall and in the plasma and the estimation of the effective electric conductivity in the discharge.

Flywheel Charge/Discharge Control Developed

NASA Technical Reports Server (NTRS)

Beach, Raymond.F.; Kenny, Barbara H.

2001-01-01

A control algorithm developed at the NASA Glenn Research Center will allow a flywheel energy storage system to interface with the electrical bus of a space power system. The controller allows the flywheel to operate in both charge and discharge modes. Charge mode is used to store additional energy generated by the solar arrays on the spacecraft during insolation. During charge mode, the flywheel spins up to store the additional electrical energy as rotational mechanical energy. Discharge mode is used during eclipse when the flywheel provides the power to the spacecraft. During discharge mode, the flywheel spins down to release the stored rotational energy.

An numerical analysis of high-temperature helium reactor power plant for co-production of hydrogen and electricity

NASA Astrophysics Data System (ADS)

Dudek, M.; Podsadna, J.; Jaszczur, M.

2016-09-01

In the present work, the feasibility of using a high temperature gas cooled nuclear reactor (HTR) for electricity generation and hydrogen production are analysed. The HTR is combined with a steam and a gas turbine, as well as with the system for heat delivery for medium temperature hydrogen production. Industrial-scale hydrogen production using copper-chlorine (Cu-Cl) thermochemical cycle is considered and compared with high temperature electrolysis. Presented cycle shows a very promising route for continuous, efficient, large-scale and environmentally benign hydrogen production without CO2 emissions. The results show that the integration of a high temperature helium reactor, with a combined cycle for electric power generation and hydrogen production, may reach very high efficiency and could possibly lead to a significant decrease of hydrogen production costs.

Role of electric discharges in the generation of atmospheric vortices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinkevich, O. A., E-mail: oleg.sinkevich@itf.mpei.ac.ru; Maslov, S. A., E-mail: sergm90@mail.ru; Gusein-zade, N. G., E-mail: ngus@mail.ru

The existing thermohydrodynamic and hydroelectromagnetic models of tornado are considered. The potentialities of the humid atmosphere as a heat engine generating air vortices are analyzed in detail. The ability of long-term atmospheric electric discharges to form a tornado funnel and create an initial twist of up to 10{sup –3}–10{sup –2} s{sup –1} in it are estimated. The possible effect of a lightning discharge on the initiation and evolution of the tornado is discussed. It is shown that the electric current flowing along the lightning channel can lead to helical instability and generation of a weak primary vortex. The channel formedmore » in the atmosphere by a lightning discharge and the vortex motion of the parent thundercloud can enhance the primary vortex and promote its transformation into a tornado. Possible mechanisms of enhancement of the primary vortex created by a lightning discharge and the possibility of its transformation into a tornado in the postdischarge stage are discussed.« less

Capacitively coupled hydrogen plasmas sustained by tailored voltage waveforms: excitation dynamics and ion flux asymmetry

DOE PAGES

Bruneau, B.; Diomede, P.; Economou, D. J.; ...

2016-06-08

Parallel plate capacitively coupled plasmas in hydrogen at relatively high pressure (~1 Torr) are excited with tailored voltage waveforms containing up to five frequencies. Predictions of a hybrid model combining a particle-in-cell simulation with Monte Carlo collisions and a fluid model are compared to phase resolved optical emission spectroscopy measurements, yielding information on the dynamics of the excitation rate in these discharges. When the discharge is excited with amplitude asymmetric waveforms, the discharge becomes electrically asymmetric, with different ion energies at each of the two electrodes. Unexpectedly, large differences in themore » $$\\text{H}_{2}^{+}$$ fluxes to each of the two electrodes are caused by the different $$\\text{H}_{3}^{+}$$ energies. When the discharge is excited with slope asymmetric waveforms, only weak electrical asymmetry of the discharge is observed. In this case, electron power absorption due to fast sheath expansion at one electrode is balanced by electron power absorption at the opposite electrode due to a strong electric field reversal.« less

Recovery curves of the surface electric field after lightning discharges occurring between the positive charge pocket and negative charge centre in a thundercloud

NASA Astrophysics Data System (ADS)

Pawar, S. D.; Kamra, A. K.

2002-12-01

Surface observations of the electric field recovery curves of the lightning discharges occurring between the positive charge pocket and negative main charge centre in an overhead thundercloud are reported. Such recovery curves are observed to have an additional step of very slow field-change observed at an after-discharge value of electric field equal to 5-6 kV m-1. The behavior of recovery curves is explained in terms of the coronae charge and the relative efficiencies of the charge generating processes responsible for growth of positive charge pocket and main negative charge centre in the thundercloud. The charging currents responsible for the growth of charge in positive charge pockets is computed to be 2-4 times larger than that for the growth of the main negative charge. However, the charge destroyed in such a discharge is found to be comparable to that in a discharge between the main charge centres of the thundercloud.

Fast optical and electrical diagnostics of pulsed spark discharges in different gap geometries

NASA Astrophysics Data System (ADS)

Höft, Hans; Huiskamp, Tom; Kettlitz, Manfred

2016-09-01

Spark discharges in different electrode configurations and with various electrode materials were ignited in air at atmospheric pressure using a custom build pulse charger with 1 μs voltage rise time (up to 28 kV) in single shot operation. Fast voltage and current measurements were combined with iCCD imaging with high spatial resolution (better than 10 μm) on pin-to-pin, pin-to-half-sphere and symmetrical half-sphere tungsten electrodes and symmetrical half-sphere brass electrodes for electrode gaps of 0.1 to 0.7 mm. Breakdown voltages, consumed electrical energies and the discharge emission structures as well as the discharge diameters were obtained. Because of the synchronization of the electrical measurements and the iCCD imaging (i.e. one complete data set for every shot), it was possible to estimate the current density and the change of the discharge pattern, such as single or multiple channels, for all cases. EU funding under Grant No 316216 (PlasmaShape).

Boundary-value problem for a counterrotating electrical discharge in an axial magnetic field. [plasma centrifuge for isotope separation

NASA Technical Reports Server (NTRS)

Hong, S. H.; Wilhelm, H. E.

1978-01-01

An electrical discharge between two ring electrodes embedded in the mantle of a cylindrical chamber is considered, in which the plasma in the anode and cathode regions rotates in opposite directions under the influence of an external axial magnetic field. The associated boundary-value problem for the coupled partial differential equations describing the azimuthal velocity and radial current-density fields is solved in closed form. The velocity, current density, induced magnetic induction, and electric fields are presented for typical Hartmann numbers, magnetic Reynolds numbers, and geometry parameters. The discharge is shown to produce anodic and cathodic plasma sections rotating at speeds of the order 1,000,000 cm/sec for conventional magnetic field intensities. Possible application of the magnetoactive discharge as a plasma centrifuge for isotope separation is discussed.

Influence of an electric probe on the anode layer of a glow discharge in nitrogen

NASA Astrophysics Data System (ADS)

Taran, M. D.; Dyatko, N. A.; Kochetov, I. V.; Napartovich, A. P.; Akishev, Yu S.

2018-05-01

A two-dimensional (2D) numerical model of a DC glow discharge in nitrogen is developed for the case when the electric probe is mounted in the discharge gap. Within this model, calculations are performed for the gas pressure of 50 Torr and discharge current densities of 22 and 90 mA cm‑2. A cylindrical probe 1 mm in diameter is located parallel to the anode at a distance of 5 or 10 mm. The probe potential is varied in a wide range relative to the floating potential. Numerical simulations predict the 2D plasma perturbation pattern induced by the electric probe and the influence of the probe on anode layer characteristics. In particular, conditions are determined under which a region with no glow forms in the anode layer.

Natural circulating passive cooling system for nuclear reactor containment structure

DOEpatents

Gou, Perng-Fei; Wade, Gentry E.

1990-01-01

A passive cooling system for the contaminant structure of a nuclear reactor plant providing protection against overpressure within the containment attributable to inadvertent leakage or rupture of the system components. The cooling system utilizes natural convection for transferring heat imbalances and enables the discharge of irradiation free thermal energy to the atmosphere for heat disposal from the system.

Heated-Pressure-Ball Monopropellant Rocket Engine

NASA Technical Reports Server (NTRS)

Greene, William D.

2005-01-01

A recent technology disclosure presents a concept for a monopropellant thermal spacecraft thruster that would feature both the simplicity of a typical prior pressure-fed propellant supply system and the smaller mass and relative compactness of a typical prior pump-fed system. The source of heat for this thruster would likely be a nuclear- fission reactor. The propellant would be a cryogenic fluid (a liquefied low-molecular-weight gas) stored in a tank at a low pressure. The propellant would flow from the tank, through a feedline, into three thick-walled spherical tanks, denoted pressure balls, that would be thermally connected to the reactor. Valves upstream and downstream of the pressure balls would be operated in a three-phase cycle in which propellant would flow into one pressure ball while the fluid underwent pressurization through heating in another ball and pressurized propellant was discharged from the remaining ball into the reactor. After flowing through the reactor, wherein it would be further heated, the propellant would be discharged through an exhaust nozzle to generate thrust. A fraction of the pressurized gas from the pressure balls would be diverted to maintain the desired pressure in the tank.

Discussion-preliminary review of the safety aspects of the crossunder line, Project CG-884. Volume 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, S.S.

1960-12-19

In order to reduce both charge-discharge shutdown time and the number of manhours of radiation exposure, Project CGI-884 is being completed at the B, D, DR, F and R Reactors. This consists essentially of installing a large drain line at the bottom of one rear reactor riser. This drain line passes to a control valve and then to the effluent line beyond the downcomer. This system by-passes the crossover downcomer part of the effluent system and eliminates the need for intermittent rear crossheader valving during reactor charge-discharge procedures. Two aspects of this system have been considered, its basic design requirements,more » and operating restrictions to ensure adequate process tube cooling. Because of the complexity of the reactor flow system approximate solutions were used to compare different methods or degrees of operation and establish limits. Despite these approximations, there was sufficient difference in the case results to justify the specific conclusions presented in this report. This report should serve the dual purpose of providing design requirements for the crossunder and also providing the technical criteria necessary for the operating standards for the use of this new system.« less

High Discharge Energy Density at Low Electric Field Using an Aligned Titanium Dioxide/Lead Zirconate Titanate Nanowire Array.

PubMed

Zhang, Dou; Liu, Weiwei; Guo, Ru; Zhou, Kechao; Luo, Hang

2018-02-01

Polymer-based capacitors with high energy density have attracted significant attention in recent years due to their wide range of potential applications in electronic devices. However, the obtained high energy density is predominantly dependent on high applied electric field, e.g., 400-600 kV mm -1 , which may bring more challenges relating to the failure probability. Here, a simple two-step method for synthesizing titanium dioxide/lead zirconate titanate nanowire arrays is exploited and a demonstration of their ability to achieve high discharge energy density capacitors for low operating voltage applications is provided. A high discharge energy density of 6.9 J cm -3 is achieved at low electric fields, i.e., 143 kV mm -1 , which is attributed to the high relative permittivity of 218.9 at 1 kHz and high polarization of 23.35 µC cm -2 at this electric field. The discharge energy density obtained in this work is the highest known for a ceramic/polymer nanocomposite at such a low electric field. The novel nanowire arrays used in this work are applicable to a wide range of fields, such as energy harvesting, energy storage, and photocatalysis.

Optical alignment of electrodes on electrical discharge machines

NASA Technical Reports Server (NTRS)

Boissevain, A. G.; Nelson, B. W.

1972-01-01

Shadowgraph system projects magnified image on screen so that alignment of small electrodes mounted on electrical discharge machines can be corrected and verified. Technique may be adapted to other machine tool equipment where physical contact cannot be made during inspection and access to tool limits conventional runout checking procedures.

Eight electrode optical readout gap

DOEpatents

Boettcher, G.E.; Crain, R.W.

1984-01-01

A protective device for a plurality of electrical circuits includes a plurality of isolated electrodes forming a gap with a common electrode. An output signal, electrically isolated from the circuits being monitored, is obtained by a photosensor viewing the discharge gap through an optical window. Radioactive stabilization of discharge characteristics is provided for slowly changing voltages and carbon tipped dynamic starters provide desirable discharge characteristics for rapidly varying voltages. A hydrogen permeation barrier is provided on external surfaces of the device.

Insulation Coordination and Failure Mitigation Concerns for Roust Dc Electrical Power Systems (Preprint)

DTIC Science & Technology

2014-05-01

vulnerable to failure is air. This could be a discharge through an air medium or along an air/surface interface. Achieving robustness in dc power...sputtering” arcs) are discharges that are most commonly located in series with the intended load; the electrical impedance of the load limits the...particularly those used at voltages > 1000 V, is detection and measurement of partial- discharge (PD) activity. The presence of PD in a component typically

Turbulent Flame Stabilization Methods Using Confinement, Diluents, and High-Potential Electric Fields

DTIC Science & Technology

2014-08-03

the corona discharge was optimal for flame stabilization when it was located where fuel/air mixtures were within flammability limits locally...field [56]. This ionic wind is also known as the “ corona wind” [57] due to the corona discharge that develops at the sharp edge of the charged... Corona Discharge ,” Transactions of the American Institute of Electrical Engineers, Part I: Communication and Electronics, vol. 80, no. 2, pp. 143-150

Ultraviolet radiation induced discharge laser

DOEpatents

Gilson, Verle A.; Schriever, Richard L.; Shearer, James W.

1978-01-01

An ultraviolet radiation source associated with a suitable cathode-anode electrode structure, disposed in a gas-filled cavity of a high pressure pulsed laser, such as a transverse electric atmosphere (TEA) laser, to achieve free electron production in the gas by photoelectric interaction between ultraviolet radiation and the cathode prior to the gas-exciting cathode-to-anode electrical discharge, thereby providing volume ionization of the gas. The ultraviolet radiation is produced by a light source or by a spark discharge.

[Anterior uveitis caused by electrical discharge in whole body injuries (fifteen years study)].

PubMed

Krásný, J; Brož, L; Kripner, J

2013-10-01

To inform about clinical analysis of early ophthalmologic complication (uveitis) in patients sustained electric discharge injury. The authors refer about fifteen years follow-up of pediatric patients at the Department of Burns Medicine, 3rd Medical Faculty, Charles University in Prague, Czech Republic, E.U., with electric discharge injury, in which the anterior uveitis was detected. Out of 43 patients after electric discharge injury, the always-unilateral iritis (iridocyclitis) was diagnosed in four (9 %) patients according to thorough going follow-up after first accidental diagnosis in the year 1998. Out of four boys aged 12 - 15 years, the first two were injured during the "play" - due to the contact with electrical trolley wire while running on railroad wagons roofs, and the two others were stuck by lighting under a tree by secondary electrical discharge. More serious skin burns were noticed in high-voltage current injury - 69 % or 55 % of body surface respectively, with the necessity of skin transplantation. The same was necessary in one boy injured by lighting with burns of 25 % of body surface, while the last one had on the skin the lighting signs only. In most of the patients, the resuscitation care due to unconsciousness and posttraumatic shock was necessary. The anterior uveitis was diagnosed subsequently, after initial preliminary diagnoses as conjunctivitis, episcleritis, or ophthalmia electrical. The iritis without visual function decrease was discovered in few days after the injury in three patients. Treatment and results: The inflammation was in these cases treated with short-term application of mydriatic and corticosteroid eye drops. Once only, the uveitis appeared after two months during the patients hospitalization and then the signs of iridocyclitis in the anterior chamber worsened and caused visual acuity decrease to hand movement in front of the eye. The condition was successfully treated by means of parabulbar betamethasone injection and long-term application of mydriatic and corticosteroid drops. Uveitis in electrical discharge injury of different origin is a rare early complication, which may be determined solely by regular ophthalmologic follow-up examinations of the patients.

Study on Ultra-Long Life,Small U-Zr Metallic Fuelled Core With Burnable Poison

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kenji Tsuji; Hiromitsu Inagaki; Akira Nishikawa

2002-07-01

A conceptual design for a 50 MWe sodium cooled, U-Pu-Zr metallic fuelled, fast reactor core, which aims at a core lifetime of 30 years, has been performed [1]. As for the compensation for a large burn-up reactivity through 30 years, an axially movable reflector, which is located around the core, carries the major part of it and a burnable poison does the rest. This concept has achieved not only a long core lifetime but also a high discharged burn-up. On this study, a conceptual design for a small fast reactor loading U-Zr metallic fuelled core instead of U-Pu-Zr fuelled coremore » has been conducted, based on the original core arrangement of 4S reactor [2]. Within the range of this study including safety requirements, adopting the burnable poison would be effective to construct a core concept that achieves both a long lifetime and a high discharged burn-up. (authors)« less

Development of a new plasma reactor for propene removal

NASA Astrophysics Data System (ADS)

Oukacine, Linda; Tatibouët, Jean-Michel

2008-10-01

The purpose of the study is to develop a new plasma reactor being applied to gas phase pollution abatement, involving a surface dielectric barrier discharge (SDBD) at atmospheric pressure. Propene was chosen as a model pollutant. The system can associate a SDBD with a volume dielectric barrier discharge (VDBD). A specific catalyst can be placed in post-plasma site in order to destroy the residual ozone after use it as a strong oxidant for total oxidation of propene and by-products formed by the plasma reactor. A comparative study has been established between the propene removal efficiency of these two plasma geometries. The results demonstrate that SDBD is a promising system for gas cleaning. The experiments show that ozone production depends on plasma system configuration and indicate the effectiveness of combining SDBD and VDBD. The NOx formation remains very low, whereas ozone formation is the highest for the SDBD. The influence of some materials on the propene removal and the ozone production were studied.

NEUTRONIC REACTOR OPERATIONAL METHOD AND CORE SYSTEM

DOEpatents

Winters, C.E.; Graham, C.B.; Culver, J.S.; Wilson, R.H.

1960-07-19

Homogeneous neutronic reactor systems are described wherein an aqueous fuel solution is continuously circulated through a spherical core tank. The pumped fuel solution-is injected tangentially into the hollow spherical interior, thereby maintaining vigorous rotation of the solution within the tank in the form of a vortex; gaseous radiolytic decomposition products concentrate within the axial vortex cavity. The evolved gas is continuously discharged through a gas- outlet port registering with an extremity of the vortex cavity. and the solution stream is discharged through an annular liquid outlet port concentrically encircling the gas outlet by virtue of which the vortex and its cavity are maintained precisely axially aligned with the gas outlet. A primary heat exchanger extracts useful heat from the hot effluent fuel solution before its recirculation into the core tank. Hollow cylinders and other alternative core- tank configurations defining geometric volumes of revolution about a principal axis are also covered. AEC's Homogeneous Reactor Experiment No. 1 is a preferred embodiment.

Scoping Calculations of Power Sources for Nuclear Electric Propulsion

NASA Technical Reports Server (NTRS)

Difilippo, F. C.

1994-01-01

This technical memorandum describes models and calculational procedures to fully characterize the nuclear island of power sources for nuclear electric propulsion. Two computer codes were written: one for the gas-cooled NERVA derivative reactor and the other for liquid metal-cooled fuel pin reactors. These codes are going to be interfaced by NASA with the balance of plant in order to make scoping calculations for mission analysis.

Laboratory Experiments of Helicity or Vortex Generation in an Electric Quadrupole: Simulation of Tonadoes with and without Lightning

NASA Astrophysics Data System (ADS)

Kikuchi, H.

2007-05-01

Laboratory Experiments of Helicity or Vortex Generation in an Electric Quadrupole: Simulation of Tornadoes with and without Lightning H. Kikuchi Institute for Environmental Electromagnetics 3-8-18, Komagome, Toshima-ku, Tokyo 170, Japan e-mail: hkikuchi@mars.dti.ne.jp Abstract Usually the source-origins of helicity or vortex generation have been considered to be thermohydrodynamic in the hydrodynamic (HD) regime and/or magnetohydrodynamic in the magnetohydrodynamic (MHD) regime. It has been shown, however, by the present author that an electric quadrupole is also capable for helicity or vortex generation and a new electric helic- ity defined as hE= v·E (v: flow velocity; E: electric field) has been introduced. Accordingly, we have now three kinds of helicity, namely fluid, magnetic, and electric helicity. In many cases of atmospheric and space electricity phenomena in nature, electric helicity or vortex generation of electric origin is involved as typically seen in tornadic thunderstorms. Conventional theory of tornadoes, however, space- charge and electric fields have never been considered properly so far, surprisingly in spite of their effects of significance, because of no theorv for such cases, although those effects have been recognized implicitly by field experiments. This paper fills up these demands by newly introducing the concept of 'Electric Helicity' based on 'Electrohydrodynamics' (EHD) established and developed over the last more than two decades and such a whole theory is applied to tornadioes with and without lightning. Further, experimental evidence of this theory is presented for the first time by using a 'universal electric-cusp type plasma reactor' designed more than a decade ago [1]. This device is composed of two positive and negative electrodes of lead spheres 1.5 cm in diameter suspended 2~5 cm above a copper plane on which a semispherical lead 1.25 cm in diameter or its modified object is placed. A whole setup is arranged in a wooden box whose back and both sides are covered by black papers to prevent scattered and reflected light while its front side is open. We are particularly focusing on 'significance of electric quadrupole(s) in helicity and vortex generation',taking photos of wind flows with the use of a bunch of incense sticks burned and placed on the semispherical lead at the cusp center in the reactor. With increasing both electrode voltages from zero to a certain kV, ascending straight wind flows turn to be cyclonic separately toward the both electrodes. As soon as electric discharge from both electrodes to object starts at a certain breakdown voltage, typically 20~30 kV, wind flows suddenly turn to be violent and wind flows toward negative electrode are still cyclonic but wind flows toward positive electrode become anticyclonic. These results are shown by a number of photos taken and provide at the same time 'laboratory simulation of tonadoes with and without lightning'. [1] Kikuchi, H. Electrohydrodynamics in Dusty and Dirty Plasmas, Kluwer Academic Publishers, Dordrecht/The Netherlands, 2001, pp.93-94.

Needle-array to Plate DBD Plasma Using Sine AC and Nanosecond Pulse Excitations for Purpose of Improving Indoor Air Quality

PubMed Central

Zhang, Li; Yang, Dezheng; Wang, Wenchun; Wang, Sen; Yuan, Hao; Zhao, Zilu; Sang, Chaofeng; Jia, Li

2016-01-01

In this study, needle-array to plate electrode configuration was employed to generate an atmospheric air diffuse discharge using both nanosecond pulse and sine AC voltage as excitation voltage for the purpose of improving indoor air quality. Different types of voltage sources and electrode configurations are employed to optimize electrical field distribution and improve discharge stability. Discharge images, electrical characteristics, optical emission spectra, and plasma gas temperatures in both sine AC discharge and nanosecond pulse discharge were compared and the discharge stability during long operating time were discussed. Compared with the discharge excited by sine AC voltage, the nanosecond pulsed discharge is more homogenous and stable, besides, the plasma gas temperature of nanosecond pulse discharge is much lower. Using packed-bed structure, where γ- Al2O3 pellets are filled in the electrode gap, has obvious efficacy in the production of homogenous discharge. Furthermore, both sine AC discharge and nanosecond pulse discharge were used for removing formaldehyde from flowing air. It shows that nanosecond pulse discharge has a significant advantage in energy cost. And the main physiochemical processes for the generation of active species and the degradation of formaldehyde were discussed. PMID:27125663

Electrically Conductive Anodized Aluminum Surfaces

NASA Technical Reports Server (NTRS)

Nguyen, Trung Hung

2006-01-01

Anodized aluminum components can be treated to make them sufficiently electrically conductive to suppress discharges of static electricity. The treatment was conceived as a means of preventing static electric discharges on exterior satin-anodized aluminum (SAA) surfaces of spacecraft without adversely affecting the thermal-control/optical properties of the SAA and without need to apply electrically conductive paints, which eventually peel off in the harsh environment of outer space. The treatment can also be used to impart electrical conductivity to anodized housings of computers, medical electronic instruments, telephoneexchange equipment, and other terrestrial electronic equipment vulnerable to electrostatic discharge. The electrical resistivity of a typical anodized aluminum surface layer lies between 10(exp 11) and 10(exp 13) Omega-cm. To suppress electrostatic discharge, it is necessary to reduce the electrical resistivity significantly - preferably to < or = 10(exp 9) Omega-cm. The present treatment does this. The treatment is a direct electrodeposition process in which the outer anodized surface becomes covered and the pores in the surface filled with a transparent, electrically conductive metal oxide nanocomposite. Filling the pores with the nanocomposite reduces the transverse electrical resistivity and, in the original intended outer-space application, the exterior covering portion of the nanocomposite would afford the requisite electrical contact with the outer-space plasma. The electrical resistivity of the nanocomposite can be tailored to a value between 10(exp 7) and 10(exp 12) Omega-cm. Unlike electrically conductive paint, the nanocomposite becomes an integral part of the anodized aluminum substrate, without need for adhesive bonding material and without risk of subsequent peeling. The electrodeposition process is compatible with commercial anodizing production lines. At present, the electronics industry uses expensive, exotic, electrostaticdischarge- suppressing finishes: examples include silver impregnated anodized, black electroless nickel, black chrome, and black copper. In comparison with these competing finishes, the present nanocomposite finishes are expected to cost 50 to 20 percent less and to last longer.

Studies of oxygen-helium discharges for use in electric oxygen-iodine lasers

NASA Astrophysics Data System (ADS)

Zimmerman, Joseph William

In recent work, the performance of the Electric Oxygen-Iodine Laser (ElectricOIL), developed in partnership by researchers at the University of Illinois and CU Aerospace, has been greatly improved through systematic study of various components of this new laser technology. One major contribution to the advancement of ElectricOIL technology has been the development of electric discharges capable of producing significant flow rates of the precursor electronically-excited molecular oxygen, O2(a1Delta). O2(a 1Delta) serves as an energy reservoir in the laser system, pumping atomic iodine by near-resonant energy transfer producing gain and laser on the I(2P1/2) → I(2P3/2 ) transition at 1315 nm. Initial experimental work with radio-frequency discharges showed the importance of controlling O-atom flow rates to reduce quenching losses of energy stored in O2(a1Delta), and determined proper selection of the helium diluent ratio and specific power deposition (power per O2 flow rate). Further experimental investigations with transverse capacitive radio-frequency discharges in O2/He/NO mixtures in the pressure range of 1-100 Torr and power range of 0.1-1.2 kW have indicated that O2(a1Delta) production is a strong function of geometry (transverse gap), excitation frequency, and pressure. These parameters along with gas flow mixture dictate the current density at which the discharge operates, and its modal characteristics (normal vs. abnormal, homogeneous vs. inhomogeneous). A key result is that to encourage efficient O2(a1Delta) production these parameters should be selected in order to promote a homogeneous (low current density) discharge. The discharge behavior is characterized using terminal current-voltage-characteristics, microwave interferometer measurements, and plasma emission intensity measurements. Numerous spectroscopic measurements of O2(a1Delta), oxygen atoms, and discharge excited states are made in order to describe the discharge performance dependent on various parameters. The influence of NO on O-atom flow rates and O2(a1Delta) production is investigated. Progress of laser power extraction since initial reports in 2005 is overviewed.

Coupling mechanism of electric vehicle and grid under the background of smart grid

NASA Astrophysics Data System (ADS)

Dong, Mingyu; Li, Dezhi; Chen, Rongjun; Shu, Han; He, Yongxiu

2018-02-01

With the development of smart distribution technology in the future, electric vehicle users can not only charge reasonably based on peak-valley price, they can also discharge electricity into the power grid to realize their economic benefit when it’s necessary and thus promote peak load shifting. According to the characteristic that future electric vehicles can discharge, this paper studies the interaction effect between electric vehicles and the grid based on TOU (time of use) Price Strategy. In this paper, four scenarios are used to compare the change of grid load after implementing TOU Price Strategy. The results show that the wide access of electric vehicles can effectively reduce peak and valley difference.

Research on charging and discharging control strategy for electric vehicles as distributed energy storage devices

NASA Astrophysics Data System (ADS)

Zhang, Min; Yang, Feng; Zhang, Dongqing; Tang, Pengcheng

2018-02-01

A large number of electric vehicles are connected to the family micro grid will affect the operation safety of the power grid and the quality of power. Considering the factors of family micro grid price and electric vehicle as a distributed energy storage device, a two stage optimization model is established, and the improved discrete binary particle swarm optimization algorithm is used to optimize the parameters in the model. The proposed control strategy of electric vehicle charging and discharging is of practical significance for the rational control of electric vehicle as a distributed energy storage device and electric vehicle participating in the peak load regulation of power consumption.

Fundamental experiment of ion thruster using ECR discharge

NASA Astrophysics Data System (ADS)

Yasui, Toshiaki; Kitayama, Jiro; Tahara, Hirokazu; Onoe, Ken-Ichi; Yoshikawa, Takao

A microwave ion thruster has the potential to overcome a lifetime problem of electric propulsion by eliminating electrodes. Two types of microwave ion thruster have been investigated to examine the operational characteristics. The one is the thruster using cavity-resonance microwave discharge, and the other is the thruster using Electron Cyclotron Resonance (ECR) discharge. Cavity-resonance microwave discharge produced plasmas by strong electric field in the resonant cavity and sustained plasmas at argon mass flow rates above 10 sccm. However, ECR discharge was capable of sustaining plasmas at lower mass flow rate, because ECR discharge efficiently produced plasmas by resonance absorption. From these generated microwave plasmas, ions were electrostatically extracted by two multiaperture grids. In ECR discharge, the maximum ion beam current of 75 mA and the highest mass utilization efficiency of 18.7% were achieved at a total extraction voltage of 950 V.

Microelectrode-assisted low-voltage atmospheric pressure glow discharge in air

NASA Astrophysics Data System (ADS)

Liu, Wenzheng; Zhao, Shuai; Niu, Jiangqi; Chai, Maolin

2017-09-01

During the process of discharge, appropriately changing the paths corresponding to electric field lines and the field strength distribution along these paths, as well as increasing the number of initial electrons, can effectively enhance the uniformity of discharge and inhibit the formation of filamentary discharge. A method is proposed that uses a microelectrode to initiate the macroscopic discharge phenomenon. An asymmetric structure was designed comprising a single electrode of carbon fiber; this electrode structure is of helical-contact type. Benefitting from the special electric field distribution and the microdischarge process, a three-dimensional atmospheric pressure glow discharge was achieved in air, characterized by low discharge voltage, low energy consumption, good diffusion performance, and less ozone generation. The plasma studied is uniform and stable with good diffusion characteristics and low levels of contaminants and hence has potential applications in the field of air purification.

Behavior of Combined Dielectric-Metallic Systems in a Charged Particle Environment

NASA Technical Reports Server (NTRS)

Gordon, W. L.; Hoffman, R. W.

1984-01-01

The charging and discharging characteristics of an electrically isolated solar array segment were studied in order to simulate discharges seen during geomagnetic substorms. A solar array segment was floated while bombarded with monoenergetic electrons at various angles of incidence. The potentials of the array surface and of the interconnects were monitored using Trek voltage probes to maintain electrical isolation. A back plate was capacitively coupled to the array to provide information on the characteristics of the transients accompanying the discharges. Several modes of discharging of the array were observed at relatively low differential and absolute potentials (a few kilovolts). A relatively slow discharge response in the array was observed, discharging over one second with currents of nanoamps. Two types of faster discharges were also seen which lasted a few hundredths of a millisecond and with currents on the order of microamps. Some results indicate an electron emission process associated with the arcs.

Contribution from the Yenisei River to the total radioactive contamination of the Kara Sea

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuznetsov, Yu.V.; Revenko, Yu.A.; Legin, V.K.

1995-07-01

An attempt is made to estimate the contribution from the Yenisei River and, therefore, the Krasnoyarsk Mining and Chemical Plant (MCP), which discharged wastewaters to the Yenisei, to the total contamination of the Kara Sea using results from a study of the radioactive contamination of the Yenisei River, Yenisei Bay, Yenisei Gulf, and the Kara Sea itself. Radionuclides generated from using river water in cooling circuits of production reactors make the largest contribution to the total activity. The radioactive contamination of the river decreased by more than 20 times after two of the three operating reactors were shut down. Onlymore » several wetlands are actually affected by MCP hundreds of kilometers from the discharge point.« less

The structure optimization of gas-phase surface discharge and its application for dye degradation

NASA Astrophysics Data System (ADS)

Ying, CAO; Jie, LI; Nan, JIANG; Yan, WU; Kefeng, SHANG; Na, LU

2018-05-01

A gas-phase surface discharge (GSD) was employed to optimize the discharge reactor structure and investigate the dye degradation. A dye mixture of methylene blue, acid orange and methyl orange was used as a model pollutant. The results indicated that the reactor structure of the GSD system with the ratio of tube inner surface area and volume of 2.48, screw pitch between a high-voltage electrode of 9.7 mm, high-voltage electrode wire diameter of 0.8 mm, dielectric tube thickness of 2.0 mm and tube inner diameter of 16.13 mm presented a better ozone (O3) generation efficiency. Furthermore, a larger screw pitch and smaller wire diameter enhanced the O3 generation. After the dye mixture degradation by the optimized GSD system, 73.21% and 50.74% of the chemical oxygen demand (COD) and total organic carbon removal rate were achieved within 20 min, respectively, and the biochemical oxygen demand (BOD) and biodegradability (BOD/COD) improved.

Removal of NO and SO2 in Corona Discharge Plasma Reactor with Water Film

NASA Astrophysics Data System (ADS)

He, Yuanji; Dong, Liming; Yang, Jiaxiang

2004-04-01

In this paper, a novel type of a corona discharge plasma reactor was designed, which consists of needle-plate-combined electrodes, in which a series of needle electrodes are placed in a glass container filled with flue gas, and a plate electrode is immersed in the water. Based on this model, the removal of NO and SO2 was tested experimentally. In addition, the effect of streamer polarity on the reduction of SO2 and NO was investigated in detail. The experimental results show that the corona wind formed between the high-voltage needle electrode and the water by corona discharge enhances the cleaning efficiency of the flue gas because of the presence of water, and the cleaning efficiency will increase with the increase of applied dc voltage within a definite range. The removal efficiency of SO2 up to 98%, and about 85% of NOx removal under suitable conditions is obtained in our experiments.

Development costs for a nuclear electric propulsion stage.

NASA Technical Reports Server (NTRS)

Mondt, J. F.; Prickett, W. Z.

1973-01-01

Development costs are presented for an unmanned nuclear electric propulsion (NEP) stage based upon a liquid metal cooled, in-core thermionic reactor. A total of 120 kWe are delivered to the thrust subsystem which employs mercury ion engines for electric propulsion. This study represents the most recent cost evaluation of the development of a reactor power system for a wide range of nuclear space power applications. These include geocentric, and outer planet and other deep space missions. The development program is described for the total NEP stage, based upon specific development programs for key NEP stage components and subsystems.

Self isolating high frequency saturable reactor

DOEpatents

Moore, James A.

1998-06-23

The present invention discloses a saturable reactor and a method for decoupling the interwinding capacitance from the frequency limitations of the reactor so that the equivalent electrical circuit of the saturable reactor comprises a variable inductor. The saturable reactor comprises a plurality of physically symmetrical magnetic cores with closed loop magnetic paths and a novel method of wiring a control winding and a RF winding. The present invention additionally discloses a matching network and method for matching the impedances of a RF generator to a load. The matching network comprises a matching transformer and a saturable reactor.

CO2 conversion in non-thermal plasma and plasma/g-C3N4 catalyst hybrid processes

NASA Astrophysics Data System (ADS)

Lu, Na; Sun, Danfeng; Zhang, Chuke; Jiang, Nan; Shang, Kefeng; Bao, Xiaoding; Li, Jie; Wu, Yan

2018-03-01

Carbon dioxide conversion at atmosphere pressure and low temperature has been studied in a cylindrical dielectric barrier discharge (DBD) reactor. Pure CO2 feed flows to the discharge zone and typical filamentary discharges were obtained in each half-cycle of the applied voltage. The gas temperature increased with discharge time and discharge power, which was found to affect the CO2 decomposition deeply. As the DBD reactor was cooled to ambient temperature, both the conversion of CO2 and the CO yield were enhanced. Especially the energy efficiencies changed slightly with the increase of discharge power and were much higher in cooling condition comparing to those without cooling. At a discharge power of 40 W, the energy efficiency under cooling condition was approximately six times more than that without cooling. Gas flow rate was observed to affect CO2 conversion and 0.1 L min-1 was obtained as optimum gas flow rate under cooling condition. In addition, the CO2 conversion rate in plasma/g-C3N4 catalyst hybrid system was twice times as that in plasma-alone system. In case of cooling, the existence of g-C3N4 catalyst contributed to a 47% increase of CO2 conversion compared to the sole plasma process. The maximum energy-efficiency with g-C3N4 was 0.26 mmol kJ-1 at 20 W, which increased by 157% compared to that without g-C3N4. The synergistic effect of DBD plasma with g-C3N4 on pure CO2 conversion was verified.

Ambient-temperature trap/release of arsenic by dielectric barrier discharge and its application to ultratrace arsenic determination in surface water followed by atomic fluorescence spectrometry

USDA-ARS?s Scientific Manuscript database

A novel dielectric barrier discharge reactor (DBDR) was utilized to trap/release arsenic coupled to hydride generation atomic fluorescence spectrometry (HGAFS). On the DBD principle, the precise and accurate control of trap/release procedures was fulfilled at ambient temperature, and an analytical m...

Percolation simulation of laser-guided electrical discharges.

PubMed

Sasaki, Akira; Kishimoto, Yasuaki; Takahashi, Eiichi; Kato, Susumu; Fujii, Takashi; Kanazawa, Seiji

2010-08-13

A three-dimensional simulation of laser-guided discharges based on percolation is presented. The model includes both local growth of a streamer due to the enhanced electric field at the streamer's tip and propagation of a leader by remote ionization such as that caused by runaway electrons. The stochastic behavior of the discharge through a preformed plasma channel is reproduced by the calculation, which shows complex path with detouring and bifurcation. The probability of guiding is investigated with respect to the ionized, conductive fraction along the channel.

The formation of ozone and UV radiation from high-power pulsed electric discharges

NASA Astrophysics Data System (ADS)

Piskarev, I. M.; Ushkanov, V. A.; Selemir, V. D.; Spirov, G. M.; Malevannaya Pikar', I. A.; Zuimach, E. A.

2008-09-01

High-power electric discharges with pulse energies of from 0.15 J to 4 kJ were studied. The yields of UV photons and ozone were found to be approximately equal, which led us to conclude that discharge conditions under which UV radiation and ozone fully destroyed each other were possible. If ozone formation was suppressed, as when a negative volume charge was created in the spark gap region, the flux of UV photons reached 3 × 1023 photons/(cm2 s).

Oxidation of ammonium sulfite by a multi-needle-to-plate gas phase pulsed corona discharge reactor

NASA Astrophysics Data System (ADS)

Ren, Hua; Lu, Na; Shang, Kefeng; Li, Jie; Wu, Yan

2013-03-01

The oxidation of ammonium sulfite in the ammonia-based flue gas desulfurization (FGD) process was investigated in a multi-needle-to-plate gas phase pulsed corona discharge reactor in this paper. The effect of several parameters, including capacitance and peak pulse voltage of discharge system, electrode gap and bubbling gas flow rate on the oxidation rate of ammonium sulfite was reviewed. The oxidation rate of ammonium sulfite could reach 47.2% at the capacitance, the peak pulse voltage, electrode gap and bubbling gas flow rate equal to 2 nF, -24.6 k V, 35 mm and 4 L min-1 within treatment time of 40 min The experimental results indicate that the gas phase pulsed discharge system with a multi-needle-to-plate electrode can oxide the ammonium sulfite. The oxidation rate increased with the applied capacitance and peak pulse voltage and decreased with the electrode gap. As the bubbling gas flow rate increased, the oxidation rate increased first and then tended to reach a stationary value. These results would be important for the process optimization of the (NH4)2SO3 to (NH4)2SO4 oxidation.

Degradation mechanisms of 4-chlorophenol in a novel gas-liquid hybrid discharge reactor by pulsed high voltage system with oxygen or nitrogen bubbling.

PubMed

Zhang, Yi; Zhou, Minghua; Hao, Xiaolong; Lei, Lecheng

2007-03-01

The effect of gas bubbling on the removal efficiency of 4-chlorophenol (4-CP) in aqueous solution has been investigated using a novel pulsed high voltage gas-liquid hybrid discharge reactor, which generates gas-phase discharge above the water surface simultaneously with the spark discharge directly in the liquid. The time for 100% of 4-CP degradation in the case of oxygen bubbling (7 min) was much shorter than that in the case of nitrogen bubbling (25 min) as plenty of hydrogen peroxide and ozone formed in oxygen atmosphere enhanced the removal efficiency of 4-CP. Except for the main similar intermediates (4-chlorocatechol, hydroquinone and 1,4-benzoquinone) produced in the both cases of oxygen and nitrogen bubbling, special intermediates (5-chloro-3-nitropyrocatechol, 4-chloro-2-nitrophenol, nitrate and nitrite ions) were produced in nitrogen atmosphere. The reaction pathway of 4-CP in the case of oxygen bubbling was oxygen/ozone attack on the radical hydroxylated derivatives of 4-CP. However, in the case of nitrogen bubbling, hydroxylation was the main reaction pathway with effect of N atom on degradation of 4-CP.

Analysis on the spectra and synchronous radiated electric field observation of cloud-to-ground lightning discharge plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cen Jianyong; Yuan Ping; Qu Haiyan

2011-11-15

According to the spectra of cloud-to-ground (CG) lightning discharge plasma captured by a slit-less spectrograph and the information of synchronous radiated electric field, the temperatures, the total intensity of spectra, the peak value of current and its action integral of discharge plasma channel have been calculated. Furthermore, the correlativity of these parameters has been analyzed for the first time. The results indicate that the total intensity of spectra has a positive correlation to the discharge current in different strokes of one CG lightning, and the temperature of discharge plasma is direct proportion to the action integral in the first returnmore » strokes of different lightning.« less

The New NASA-STD-4005 and NASA-HDBK-4006, Essentials for Direct-Drive Solar Electric Propulsion

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.

2007-01-01

High voltage solar arrays are necessary for direct-drive solar electric propulsion, which has many advantages, including simplicity and high efficiency. Even when direct-drive is not used, the use of high voltage solar arrays leads to power transmission and conversion efficiencies in electric propulsion Power Management and Distribution. Nevertheless, high voltage solar arrays may lead to temporary power disruptions, through the so-called primary electrostatic discharges, and may permanently damage arrays, through the so-called permanent sustained discharges between array strings. Design guidance is needed to prevent these solar array discharges, and to prevent high power drains through coupling between the electric propulsion devices and the high voltage solar arrays. While most electric propulsion systems may operate outside of Low Earth Orbit, the plasmas produced by their thrusters may interact with the high voltage solar arrays in many ways similarly to Low Earth Orbit plasmas. A brief description of previous experiences with high voltage electric propulsion systems will be given in this paper. There are two new official NASA documents available free through the NASA Standards website to help in designing and testing high voltage solar arrays for electric propulsion. They are NASA-STD-4005, the Low Earth Orbit Spacecraft Charging Design Standard, and NASA-HDBK-4006, the Low Earth Orbit Spacecraft Charging Design Handbook. Taken together, they can both educate the high voltage array designer in the engineering and science of spacecraft charging in the presence of dense plasmas and provide techniques for designing and testing high voltage solar arrays to prevent electrical discharges and power drains.

Study of SF6 gas decomposition products based on spectroscopy technology

NASA Astrophysics Data System (ADS)

Cai, Ji-xing; Na, Yan-xiang; Ni, Wei-yuan; Li, Guo-wei; Feng, Ke-cheng; Song, Gui-cai

2011-08-01

With the rapid development of power industry, the number of SF6 electrical equipment are increasing, it has gradually replaced the traditional insulating oil material as insulation and arc media in the high-voltage electrical equipment. Pure SF6 gas has excellent insulating properties and arc characteristics; however, under the effect of the strong arc, SF6 gas will decompose and generate toxic substances, then corroding electrical equipment, thereby affecting the insulation and arc ability of electrical equipment. If excessive levels of impurities in the gas that will seriously affect the mechanical properties, breaking performance and electrical performance of electrical equipment, it will cause many serious consequences, even threaten the safe operation of the grid. This paper main analyzes the basic properties of SF6 gas and the basic situation of decomposition in the discharge conditions, in order to simulate the actual high-voltage electrical equipment, designed and produced a simulation device that can simulate the decomposition of SF6 gas under a high voltage discharge, and using fourier transform infrared spectroscopy to analyze the sample that produced by the simulation device. The result show that the main discharge decomposition product is SO2F2 (sulfuryl fluoride), the substance can react with water and generate corrosive H2SO4(sulfuric acid) and HF (hydrogen fluoride), also found that the increase in the number with the discharge, SO2F2concentration levels are on the rise. Therefore, the material can be used as one of the main characteristic gases to determine the SF6 electrical equipment failure, and to monitor their concentration levels.

High Voltage Discharge Profile on Soil Breakdown Using Impulse Discharge

NASA Astrophysics Data System (ADS)

Fajingbesi, F. E.; Midi, N. S.; Elsheikh, E. M. A.; Yusoff, S. H.

2017-06-01

Grounding terminals are mandatory in electrical appliance design as they provide safety route during overvoltage faults. The soil (earth) been the universal ground is assumed to be at zero electric potential. However, due to properties like moisture, pH and available nutrients; the electric potential may fluctuate between positive and negative values that could be harmful for internally connected circuits on the grounding terminal. Fluctuations in soil properties may also lead to current crowding effect similar to those seen at the emitters of semiconductor transistors. In this work, soil samples are subjected to high impulse voltage discharge and the breakdown characteristics was profiled. The results from profiling discharge characteristics of soil in this work will contribute to the optimization of grounding protection system design in terms of electrode placement. This would also contribute to avoiding grounding electrode current crowding, ground potential rise fault and electromagnetic coupling faults.

Traveling wire electrode increases productivity of Electrical Discharge Machining /EDM/ equipment

NASA Technical Reports Server (NTRS)

Kotora, J., Jr.; Smith, S. V.

1967-01-01

Traveling wire electrode on electrical discharge machining /EDM/ equipment reduces the time requirements for precision cutting. This device enables cutting with a minimum of lost material and without inducing stress beyond that inherent in the material. The use of wire increases accuracy and enables tighter tolerances to be maintained.

46 CFR 129.540 - Remote stopping-systems on OSVs of 100 or more gross tons.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) OFFSHORE SUPPLY VESSELS ELECTRICAL INSTALLATIONS Miscellaneous Electrical Systems § 129.540 Remote stopping... subpart 111.103 of this chapter: (1) For each propulsion unit, in the pilothouse. (2) For each discharge pump for bilge slop or dirty oil, at the deck discharge. (3) For each powered ventilation system...

Study of a DC gas discharge with a copper cathode in a water flow

NASA Astrophysics Data System (ADS)

Tazmeev, G. Kh.; Timerkaev, B. A.; Tazmeev, Kh. K.

2017-07-01

A dc gas discharge between copper electrodes in the current range of 5-20 A was studied experimentally. The discharge gap length was varied within 45-70 mm. The cathode was a 10-mm-diameter rod placed in the water flowing out from a dielectric tube. Three discharge configurations differing in the position of the cathode upper end with respect to the water surface were considered: (i) above water; (ii) flush with the water surface, and (iii) under water. The electric and optical characteristics of the discharge in the second configuration were studied in more detail. It is established that the discharge properties are similar to those of an electric arc. Considerable cathode erosion was observed in the third configuration. It is revealed that fine-dispersed copper grains form in the course of erosion.

Nonthermal Biological Treatments Using Discharge Plasma Produced by Pulsed Power 4. Cleaning of Lakes and Marshes by Pulsed Power Produced Streamer Discharges in Water

NASA Astrophysics Data System (ADS)

Akiyama, Hidenori; Katsuki, Sunao; Namihira, Takao; Ishibashi, Kazuo; Kiyosaki, Noriaki

Pulsed power has been used to produce non-thermal plasmas in atmospheric pressure gases that generate a high electric field at the tips of streamer discharges, where high energy electrons, free radicals, ultraviolet rays, and ozone are produced. These manifestations of streamer discharges have been used in the treatment of exhaust gases, removal of volatile and toxic compounds such as dioxin, and the sterilization of microorganisms. Here, large volume streamer discharges in water are described. These streamer discharges in liquids are able to produce a high electric field, high energy electrons, ozone, chemically active species, ultraviolet rays, and shock waves, which readily sterilize microorganisms and decompose molecules and materials. An application of this phenomenon to the cleaning of lakes and marshes is also described.

Design of megawatt power level heat pipe reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mcclure, Patrick Ray; Poston, David Irvin; Dasari, Venkateswara Rao

An important niche for nuclear energy is the need for power at remote locations removed from a reliable electrical grid. Nuclear energy has potential applications at strategic defense locations, theaters of battle, remote communities, and emergency locations. With proper safeguards, a 1 to 10-MWe (megawatt electric) mobile reactor system could provide robust, self-contained, and long-term power in any environment. Heat pipe-cooled fast-spectrum nuclear reactors have been identified as a candidate for these applications. Heat pipe reactors, using alkali metal heat pipes, are perfectly suited for mobile applications because their nature is inherently simpler, smaller, and more reliable than “traditional” reactors.more » The goal of this project was to develop a scalable conceptual design for a compact reactor and to identify scaling issues for compact heat pipe cooled reactors in general. Toward this goal two detailed concepts were developed, the first concept with more conventional materials and a power of about 2 MWe and a the second concept with less conventional materials and a power level of about 5 MWe. A series of more qualitative advanced designs were developed (with less detail) that show power levels can be pushed to approximately 30 MWe.« less

LOFT. Reactor apparatus leaves A&M building (TAN607). Shielded locomotive has ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

LOFT. Reactor apparatus leaves A&M building (TAN-607). Shielded locomotive has aerojet logo, which replaced old general electric logo, pulls reactor from assembly shop on dolly. Camera facing easterly. Date: 1973. INEEL negative no. 73-3700 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

METHOD AND APPARATUS FOR EXAMINING FUEL ELEMENTS FOR LEAKAGE

DOEpatents

Smith, R.R.; Echo, M.W.; Doe, C.B.

1963-12-31

A process and a device for the continuous monitoring of fuel elements while in use in a liquid-metal-cooled, argonblanketed nuclear reactor are presented. A fraction of the argon gas is withdrawn, contacted with a negative electrical charge for attraction of any alkali metal formed from argon by neutron reaction, and recycled into the reactor. The electrical charge is introduced into water, and the water is examined for radioactive alkali metals. (AEC)

APPARATUS FOR DETECTING AND LOCATING PRESENCE OF FLUIDS

DOEpatents

Williamson, R.R.

1958-09-16

A system is described fur detecting water leaks in water-cooled neutronic reactors by utilizing an electrical hygrometer having a resistance element variable with the moisture content. The graphite blocks, forming the moderator in many types of reactors, coniain ducts in which helium gas is circulated. When a leak occurs in a coolant tube, the water will seep through the graphite until it oozes into one of the helium ducts, where it will be swept along with the helium into a system of pipes that connect each of the helium ducts. By inserting an electric hygrometer in each of these pipes and connecting it to an alarm system, the moisture content of the helium will cause a change in the electrical resistance of the hygrometer which will initiate a signal alarm indicating the presence and position of the leaky water tube in the reactor.

New, efficient and viable system for ethanol fuel utilization on combined electric/internal combustion engine vehicles

NASA Astrophysics Data System (ADS)

Sato, André G.; Silva, Gabriel C. D.; Paganin, Valdecir A.; Biancolli, Ana L. G.; Ticianelli, Edson A.

2015-10-01

Although ethanol can be directly employed as fuel on polymer-electrolyte fuel cells (PEMFC), its low oxidation kinetics in the anode and the crossover to the cathode lead to a substantial reduction of energy conversion efficiency. However, when fuel cell driven vehicles are considered, the system may include an on board steam reformer for converting ethanol into hydrogen, but the hydrogen produced contains carbon monoxide, which limits applications in PEMFCs. Here, we present a system consisting of an ethanol dehydrogenation catalytic reactor for producing hydrogen, which is supplied to a PEMFC to generate electricity for electric motors. A liquid by-product effluent from the reactor can be used as fuel for an integrated internal combustion engine, or catalytically recycled to extract more hydrogen molecules. Power densities comparable to those of a PEMFC operating with pure hydrogen are attained by using the hydrogen rich stream produced by the ethanol dehydrogenation reactor.

Fission-powered in-core thermoacoustic sensor

DOE PAGES

Garrett, Steven L.; Smith, James A.; Smith, Robert W. M.; ...

2016-04-07

A thermoacoustic engine is operated within the core of a nuclear reactor to acoustically telemeter coolant temperature (frequency-encoded) and reactor power level (amplitude-encoded) outside the reactor, thus providing the values of these important parameters without external electrical power or wiring. We present data from two hydrophones in the coolant (far from the core) and an accelerometer attached to a structure outside the reactor. Furthermore, these signals have been detected even in the presence of substantial background noise generated by the reactor's fluid pumps.

Fission-powered in-core thermoacoustic sensor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garrett, Steven L.; Smith, James A.; Smith, Robert W. M.

2016-04-04

A thermoacoustic engine is operated within the core of a nuclear reactor to acoustically telemeter coolant temperature (frequency-encoded) and reactor power level (amplitude-encoded) outside the reactor, thus providing the values of these important parameters without external electrical power or wiring. We present data from two hydrophones in the coolant (far from the core) and an accelerometer attached to a structure outside the reactor. These signals have been detected even in the presence of substantial background noise generated by the reactor's fluid pumps.

Laboratory facility for testing electric-vehicle batteries Test rig for simulating duty cycles with different discharge modes

NASA Astrophysics Data System (ADS)

Hamilton, J. A.; Rand, D. A. J.

1983-03-01

A test rig has been designed and constructed to examine the performance of batteries under laboratory conditions that simulate the power characteristics of electric vehicles. Each station in the rig subjects a battery to continuous charge/discharge cycles, with an equalising charge every eighth cycle. The battery discharge follows the current-verse-time profile of a given vehicle operating under a driving schedule normal to road service. The test rig allows both smooth- and pulsed-current discharge to be investigated. Data collection is accomplished either with multi-pen recorders or with a computer-based information logger.

PBF Reactor Building (PER620). Camera is in cab of electricpowered ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PBF Reactor Building (PER-620). Camera is in cab of electric-powered rail crane and facing east. Reactor pit and storage canal have been shaped. Floors for wings on east and west side are above and below reactor in view. Photographer: Larry Page. Date: August 23, 1967. INEEL negative no. 67-4403 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

Small Reactor for Deep Space Exploration

ScienceCinema

none,

2018-06-06

This is the first demonstration of a space nuclear reactor system to produce electricity in the United States since 1965, and an experiment demonstrated the first use of a heat pipe to cool a small nuclear reactor and then harvest the heat to power a Stirling engine at the Nevada National Security Site's Device Assembly Facility confirms basic nuclear reactor physics and heat transfer for a simple, reliable space power system.

Small-scale nuclear reactors for remote military operations: opportunities and challenges

DTIC Science & Technology

2015-08-25

study – Report was published in March 2011  CNA study identified challenges to deploy small modular reactors (SMRs) at a base – Identified First-of...forward operating bases. The availability of deployable, cost-effective, regulated, and secure small modular reactors with a modest output electrical...defense committees on the challenges, operational requirements, constraints, cost, and life cycle analysis for a small modular reactor of less than 10

An underground nuclear power station using self-regulating heat-pipe controlled reactors

DOEpatents

Hampel, V.E.

1988-05-17

A nuclear reactor for generating electricity is disposed underground at the bottom of a vertical hole that can be drilled using conventional drilling technology. The primary coolant of the reactor core is the working fluid in a plurality of thermodynamically coupled heat pipes emplaced in the hole between the heat source at the bottom of the hole and heat exchange means near the surface of the earth. Additionally, the primary coolant (consisting of the working fluid in the heat pipes in the reactor core) moderates neutrons and regulates their reactivity, thus keeping the power of the reactor substantially constant. At the end of its useful life, the reactor core may be abandoned in place. Isolation from the atmosphere in case of accident or for abandonment is provided by the operation of explosive closures and mechanical valves emplaced along the hole. This invention combines technology developed and tested for small, highly efficient, space-based nuclear electric power plants with the technology of fast- acting closure mechanisms developed and used for underground testing of nuclear weapons. This invention provides a nuclear power installation which is safe from the worst conceivable reactor accident, namely, the explosion of a nuclear weapon near the ground surface of a nuclear power reactor. 5 figs.

Underground nuclear power station using self-regulating heat-pipe controlled reactors

DOEpatents

Hampel, Viktor E.

1989-01-01

A nuclear reactor for generating electricity is disposed underground at the bottom of a vertical hole that can be drilled using conventional drilling technology. The primary coolant of the reactor core is the working fluid in a plurality of thermodynamically coupled heat pipes emplaced in the hole between the heat source at the bottom of the hole and heat exchange means near the surface of the earth. Additionally, the primary coolant (consisting of the working flud in the heat pipes in the reactor core) moderates neutrons and regulates their reactivity, thus keeping the power of the reactor substantially constant. At the end of its useful life, the reactor core may be abandoned in place. Isolation from the atmosphere in case of accident or for abandonment is provided by the operation of explosive closures and mechanical valves emplaced along the hole. This invention combines technology developed and tested for small, highly efficient, space-based nuclear electric power plants with the technology of fast-acting closure mechanisms developed and used for underground testing of nuclear weapons. This invention provides a nuclear power installation which is safe from the worst conceivable reactor accident, namely, the explosion of a nuclear weapon near the ground surface of a nuclear power reactor.

Development of electrical test procedures for qualification of spacecraft against EID. Volume 1: The CAN test and other relevant data

NASA Technical Reports Server (NTRS)

Wilkenfeld, J. M.; Judge, R. J. R.; Harlacher, B. L.

1982-01-01

A combined experimental and analytical program to develop system electrical test procedures for the qualification of spacecraft against damage produced by space-electron-induced discharges (EID) occurring on spacecraft dielectric outer surfaces is described. The data on the response of a simple satellite model, called CAN, to electron-induced discharges is presented. The experimental results were compared to predicted behavior and to the response of the CAN to electrical injection techniques simulating blowoff and arc discharges. Also included is a review of significant results from other ground tests and the P78-2 program to form a data base from which is specified those test procedures which optimally simulate the response of spacecraft to EID. The electrical and electron spraying test data were evaluated to provide a first-cut determination of the best methods for performance of electrical excitation qualification tests from the point of view of simulation fidelity.

Pressurized fluidized bed reactor

DOEpatents

Isaksson, J.

1996-03-19

A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.

Pressurized fluidized bed reactor

DOEpatents

Isaksson, Juhani

1996-01-01

A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.

40 CFR 63.543 - Standards for process sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... (a) No owner or operator of a secondary lead smelter shall discharge or cause to be discharged into the atmosphere from any existing, new, or reconstructed blast, reverberatory, rotary, or electric... discharge or cause to be discharged into the atmosphere from any existing, new, or reconstructed blast...

Cross-flow electrochemical reactor cells, cross-flow reactors, and use of cross-flow reactors for oxidation reactions

DOEpatents

Balachandran, Uthamalingam; Poeppel, Roger B.; Kleefisch, Mark S.; Kobylinski, Thaddeus P.; Udovich, Carl A.

1994-01-01

This invention discloses cross-flow electrochemical reactor cells containing oxygen permeable materials which have both electron conductivity and oxygen ion conductivity, cross-flow reactors, and electrochemical processes using cross-flow reactor cells having oxygen permeable monolithic cores to control and facilitate transport of oxygen from an oxygen-containing gas stream to oxidation reactions of organic compounds in another gas stream. These cross-flow electrochemical reactors comprise a hollow ceramic blade positioned across a gas stream flow or a stack of crossed hollow ceramic blades containing a channel or channels for flow of gas streams. Each channel has at least one channel wall disposed between a channel and a portion of an outer surface of the ceramic blade, or a common wall with adjacent blades in a stack comprising a gas-impervious mixed metal oxide material of a perovskite structure having electron conductivity and oxygen ion conductivity. The invention includes reactors comprising first and second zones seprated by gas-impervious mixed metal oxide material material having electron conductivity and oxygen ion conductivity. Prefered gas-impervious materials comprise at least one mixed metal oxide having a perovskite structure or perovskite-like structure. The invention includes, also, oxidation processes controlled by using these electrochemical reactors, and these reactions do not require an external source of electrical potential or any external electric circuit for oxidation to proceed.

Reactor power system deployment and startup

NASA Technical Reports Server (NTRS)

Wetch, J. R.; Nelin, C. J.; Britt, E. J.; Klein, G.

1985-01-01

This paper addresses issues that should receive further examination in the near-term as concept selection for development of a U.S. space reactor power system is approached. The issues include: the economics, practicality and system reliability associated with transfer of nuclear spacecraft from low earth shuttle orbits to operational orbits, via chemical propulsion versus nuclear electric propulsion; possible astronaut supervised reactor and nuclear electric propulsion startup in low altitude Shuttle orbit; potential deployment methods for nuclear powered spacecraft from Shuttle; the general public safety of low altitude startup and nuclear safe and disposal orbits; the question of preferred reactor power level; and the question of frozen versus molten alkali metal coolant during launch and deployment. These issues must be considered now because they impact the SP-100 concept selection, power level selection, weight and size limits, use of deployable radiators, reliability requirements, and economics, as well as the degree of need for and the urgency of developing space reactor power systems.

Particle-in-cell simulations of bounded plasma discharges applied to low pressure high density sources and positive columns

NASA Astrophysics Data System (ADS)

Kawamura, Emi

Particle-in-cell (PIC) simulations of bounded plasma discharges are attractive because the fields and the particle motion can be obtained self-consistently from first principles. Thus, we can accurately model a wide range of nonlocal and kinetic behavior. The only disadvantage is that PIC may be computationally expensive compared to other methods. Fluid codes, for example, may run faster but make assumptions about the bulk plasma velocity distributions and ignore kinetic effects. In Chapter 1, we demonstrate methods of accelerating PIC simulations of bounded plasma discharges. We find that a combination of physical and numerical methods makes run-times for PIC codes much more competitive with other types of codes. In processing plasmas, the ion energy distributions (IEDs) arriving at the wafer target are crucial in determining ion anisotropy and etch rates. The current trend for plasma reactors is towards lower gas pressure and higher plasma density. In Chapter 2, we review and analyze IEDs arriving at the target of low pressure high density rf plasma reactors. In these reactors, the sheath is typically collisionless. We then perform PIC simulations of collisionless rf sheaths and find that the key parameter governing the shape of the TED at the wafer is the ratio of the ion transit time across the sheath over the rf period. Positive columns are the source of illumination in fluorescent mercury-argon lamps. The efficiency of light production increases with decreasing gas pressure and decreasing discharge radius. Most current lamp software is based on the local concept even though low pressure lighting discharges tend to be nonlocal. In Chapter 3, we demonstrate a 1d3v radial PIC model to conduct nonlocal kinetic simulations of low pressure, small radius positive columns. When compared to other available codes, we find that our PIC code makes the least approximations and assumptions and is accurate and stable over a wider parameter range. We analyze the PIC simulation results in detail and find that the radial electron heat flow, which is neglected in local models, plays a major role in maintaining the global power balance. In Chapter 2, we focused on the sheaths of low pressure high density plasma reactors. In Chapter 4, we extend our study to the bulk and presheaths. Typical industrial plasma reactors often use gases with complex chemistries which tend to generate discharges containing negative ions. For high density electronegative plasmas with low gas pressure, we expect Coulomb collisions between positive and negative ions to dominate over collisions between ions and neutrals. We incorporate a Coulomb collision model into our PIC code to study the effect of this ion-ion Coulomb scattering. We find that the Coulomb collisions between the positive and negative ions significantly modify the negative ion flux, density and kinetic energy profiles.

Phase-locking behavior in a high-frequency gymnotiform weakly electric fish, Adontosternarchus.

PubMed

Kawasaki, Masashi; Leonard, John

2017-02-01

An apteronotid weakly electric fish, Adontosternarchus, emits high-frequency electric organ discharges (700-1500 Hz) which are stable in frequency if no other fish or artificial signals are present. When encountered with an artificial signal of higher frequency than the fish's discharge, the fish raised its discharge frequency and eventually matched its own frequency to that of the artificial signal. At this moment, phase locking was observed, where the timing of the fish's discharge was precisely stabilized at a particular phase of the artificial signal over a long period of time (up to minutes) with microsecond precision. Analyses of the phase-locking behaviors revealed that the phase values of the artificial stimulus at which the fish stabilizes the phase of its own discharge (called lock-in phases) have three populations between -180° and +180°. During the frequency rise and the phase-locking behavior, the electrosensory system is exposed to the mixture of feedback signals from its electric organ discharges and the artificial signal. Since the signal mixture modulates in both amplitude and phase, we explored whether amplitude or phase information participated in driving the phase-locking behavior, using a numerical model. The model which incorporates only amplitude information well predicted the three populations of lock-in phases. When phase information was removed from the electrosensory stimulus, phase-locking behavior was still observed. These results suggest that phase-locking behavior of Adontosternarchus requires amplitude information but not phase information available in the electrosensory stimulus.

Plasma reactor waste management systems

NASA Technical Reports Server (NTRS)

Ness, Robert O., Jr.; Rindt, John R.; Ness, Sumitra R.

1992-01-01

The University of North Dakota is developing a plasma reactor system for use in closed-loop processing that includes biological, materials, manufacturing, and waste processing. Direct-current, high-frequency, or microwave discharges will be used to produce plasmas for the treatment of materials. The plasma reactors offer several advantages over other systems, including low operating temperatures, low operating pressures, mechanical simplicity, and relatively safe operation. Human fecal material, sunflowers, oats, soybeans, and plastic were oxidized in a batch plasma reactor. Over 98 percent of the organic material was converted to gaseous products. The solids were then analyzed and a large amount of water and acid-soluble materials were detected. These materials could possibly be used as nutrients for biological systems.

Hydrogen Generation by Koh-Ethanol Plasma Electrolysis Using Double Compartement Reactor

NASA Astrophysics Data System (ADS)

Saksono, Nelson; Sasiang, Johannes; Dewi Rosalina, Chandra; Budikania, Trisutanti

2018-03-01

This study has successfully investigated the generation of hydrogen using double compartment reactor with plasma electrolysis process. Double compartment reactor is designed to achieve high discharged voltage, high concentration, and also reduce the energy consumption. The experimental results showed the use of double compartment reactor increased the productivity ratio 90 times higher compared to Faraday electrolysis process. The highest hydrogen production obtained is 26.50 mmol/min while the energy consumption can reach up 1.71 kJ/mmol H2 at 0.01 M KOH solution. It was shown that KOH concentration, addition of ethanol, cathode depth, and temperature have important effects on hydrogen production, energy consumption, and process efficiency.

Effect of reactor loading on atomic oxygen concentration as measured by NO chemiluminescence

NASA Technical Reports Server (NTRS)

Lerner, N. R.

1989-01-01

It has previously been observed that the etch rate of polyethylene samples in the afterglow of an RF discharge in oxygen increases with reactor loading. This enhancement of the etch rate is attributed to reactive gas phase products of the polymer etching. In the present work, emission spectroscopy is employed to examine the species present in the gas phase during etching of polyethylene. In particular, the concentration of atomic oxygen downstream from the polyethylene samples is studied as a function of the reactor loading. It is found that the concentration of atomic oxygen increases as the reactor loading is increased. The increase of etch rate with increased reactor loading is attributed to the increase of atomic oxygen concentration in the vicinity of the sample.

Particle-in-Cell Simulations of the Twisted Magnetospheres of Magnetars. I.

NASA Astrophysics Data System (ADS)

Chen, Alexander Y.; Beloborodov, Andrei M.

2017-08-01

The magnetospheres of magnetars are believed to be filled with electron-positron plasma generated by electric discharge. We present a first numerical experiment demonstrating this process in an axisymmetric magnetosphere with a simple threshold prescription for pair creation, which is applicable to the inner magnetosphere with an ultrastrong field. The {e}+/- discharge occurs in response to the twisting of the closed magnetic field lines by a shear deformation of the magnetar surface, which launches electric currents into the magnetosphere. The simulation shows the formation of an electric “gap” with an unscreened electric field ({\\boldsymbol{E}}\\cdot {\\boldsymbol{B}}\

TSS-1R Failure Mode Evaluation

NASA Technical Reports Server (NTRS)

Vaughn, Jason A.; McCollum, Matthew B.; Kamenetzky, Rachel R.

1997-01-01

Soon after the break of the tether during the Tethered Satellite System (TSS-1R) mission in February, 1996, a Tiger Team was assembled at the George C. Marshall Space Flight Center to determine the tether failure mode. One possible failure scenario was the Kevlar' strength member of the tether failed because of degradation due to electrical discharge or electrical arcing. During the next several weeks, extensive electrical discharge testing in low vacuum and plasma environments was conducted in an attempt to reproduce the electrical activity recorded by on-board science instruments during the mission. The results of these tests are presented in this paper.

Data feature: 1996 world nuclear electricity production

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-12-01

Detailed data on electricity supplied by nuclear power reactors in 1996 are provided. Figures from the International Atomic Energy Agency indicate that a total of 32 countries worldwide were operating 441 nuclear power plants with an installed capacity of 350,411 GWe, and that 36 commercial nuclear power plant units in 14 different countries with an aggregate installed capacity of 27,928 GWe were under construction. Worldwide nuclear generated electricity increased by 3.6% from 1995 to 1996, providing 17.3% of the world`s electricity production. Data for individual countries and regional totals, including generation and consumption data by source, are provided for Westernmore » Europe, Eastern Europe, the Commonwealth of Independent States, the Far East, Canada, and the United States. Other information provided includes 1996 commercial startups, decommissioning, reactor load factors, imports and exports, and gross electricity production.« less

High Discharge Energy Density at Low Electric Field Using an Aligned Titanium Dioxide/Lead Zirconate Titanate Nanowire Array

PubMed Central

Zhang, Dou; Liu, Weiwei; Guo, Ru; Zhou, Kechao

2017-01-01

Abstract Polymer‐based capacitors with high energy density have attracted significant attention in recent years due to their wide range of potential applications in electronic devices. However, the obtained high energy density is predominantly dependent on high applied electric field, e.g., 400–600 kV mm−1, which may bring more challenges relating to the failure probability. Here, a simple two‐step method for synthesizing titanium dioxide/lead zirconate titanate nanowire arrays is exploited and a demonstration of their ability to achieve high discharge energy density capacitors for low operating voltage applications is provided. A high discharge energy density of 6.9 J cm−3 is achieved at low electric fields, i.e., 143 kV mm−1, which is attributed to the high relative permittivity of 218.9 at 1 kHz and high polarization of 23.35 µC cm−2 at this electric field. The discharge energy density obtained in this work is the highest known for a ceramic/polymer nanocomposite at such a low electric field. The novel nanowire arrays used in this work are applicable to a wide range of fields, such as energy harvesting, energy storage, and photocatalysis. PMID:29610724

AC Glow Discharge Plasma in N2O

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yousif, F. B.; Martinez, H.; Robledo-Martinez, A.

2006-12-04

This paper considers the optical and electrical characterization of AC glow discharge plasma in the abnormal glow mode used for optical emission spectroscopy. The total discharge current and applied voltage are measured using conventional techniques. The electrical characteristics of the planer-cathode glow discharge confirmed that the plasma is operating at abnormal discharge mode characterized by the increases in the operating voltage as the current was raised under given pressure. Optical emission spectroscopy was used to determine the main emission lines of the glow discharge plasma of N2O at pressures between 0.5 and 4.0 Torr. It shows that the discharge emissionmore » range is mainly within 300-400 nm. The emission lines correspond to NO, O2, and O{sub 2}{sup +} are the dominant lines in the glow discharge plasma in the present study. Intensity of the emission lines show linear increase with the discharge current up to 0.4 A followed by saturation at higher currents. No emission lines were observed in this work corresponding to atomic oxygen or nitrogen.« less

A Comparison of Inductive Sensors in the Characterization of Partial Discharges and Electrical Noise Using the Chromatic Technique.

PubMed

Ardila-Rey, Jorge Alfredo; Montaña, Johny; de Castro, Bruno Albuquerque; Schurch, Roger; Covolan Ulson, José Alfredo; Muhammad-Sukki, Firdaus; Bani, Nurul Aini

2018-03-29

Partial discharges (PDs) are one of the most important classes of ageing processes that occur within electrical insulation. PD detection is a standardized technique to qualify the state of the insulation in electric assets such as machines and power cables. Generally, the classical phase-resolved partial discharge (PRPD) patterns are used to perform the identification of the type of PD source when they are related to a specific degradation process and when the electrical noise level is low compared to the magnitudes of the PD signals. However, in practical applications such as measurements carried out in the field or in industrial environments, several PD sources and large noise signals are usually present simultaneously. In this study, three different inductive sensors have been used to evaluate and compare their performance in the detection and separation of multiple PD sources by applying the chromatic technique to each of the measured signals.

Electrical and optical properties of Ar/NH{sub 3} atmospheric pressure plasma jet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, Zheng-Shi, E-mail: changzhsh1984@163.com, E-mail: gjzhang@xjtu.edu.cn; Yao, Cong-Wei; Chen, Si-Le

Inspired by the Penning effect, we obtain a glow-like plasma jet by mixing ammonia (NH{sub 3}) into argon (Ar) gas under atmospheric pressure. The basic electrical and optical properties of an atmospheric pressure plasma jet (APPJ) are investigated. It can be seen that the discharge mode transforms from filamentary to glow-like when a little ammonia is added into the pure argon. The electrical and optical analyses contribute to the explanation of this phenomenon. The discharge mode, power, and current density are analyzed to understand the electrical behavior of the APPJ. Meanwhile, the discharge images, APPJ's length, and the components ofmore » plasma are also obtained to express its optical characteristics. Finally, we diagnose several parameters, such as gas temperature, electron temperature, and density, as well as the density number of metastable argon atoms of Ar/NH{sub 3} APPJ to help judge the usability in its applications.« less

Reaction of Cl- ions in electrolyte solution induced electrical discharge plasma in the presence of argon fine bubbles

NASA Astrophysics Data System (ADS)

Hayashi, Yui; Takada, Noriharu; Wahyudiono, Kanda, Hideki; Goto, Motonobu

2017-05-01

Active chlorine species such as chlorine molecules and hypochlorous acid have been known as high performance sanitizers. They would act more reactive on chemical and biological substances when an electrical discharge was introduced in water containing an electrolyte substance. Here, the reaction of chloride (Cl-) ions were examined by introducing of a pulsed discharge plasma in sodium chloride (NaCl) solution as an electrolyte solution at room temperature. The results show that a large electrical current generated by the pulsed discharge plasma affected the reaction of Cl- ions to result available chlorine. The reaction pathway for available chlorine production was assumed similar with the reaction pathway as electrolysis. A pulsed discharge plasma in NaCl solution in the presence of argon (Ar) fine bubbles exhibited intense emissions and high electron density compared to when no Ar fine bubbles were introduced. At these conditions, the dissociation reaction rate of water increased drastically leads to the formation of 0 atoms. As a result, the reaction of Cl- ions and the available chlorine generation were also increased.