WorldWideScience

Sample records for afterburners

  1. Combined catalytic converter and afterburner

    Energy Technology Data Exchange (ETDEWEB)

    Ma, T.T.-H.

    1994-11-30

    This patent describes the combined use of a catalytic converter and afterburner. An afterburner chamber and a catalyst matrix are disposed in series within a casing. A combustible premixed charge is ignited in the afterburner chamber before it enters the catalyst matrix. This invention overcomes the problem encountered in previous designs of some of the premixed charge passing unreacted through the device unless a very long afterburner chamber is used. (UK)

  2. MIXING PHENOMENA IN INDUSTRIAL FUME AFTERBURNER SYSTEMS

    Science.gov (United States)

    The report reviews the physical-mixing phenomena involved in the reactions that occur in afterburners or fume incinerators. It considers mixing in after-burners from three points of view. It first covers typical designs of afterburner components that are involved in the mixing ph...

  3. Building an Efficient Model for Afterburn Energy Release

    Energy Technology Data Exchange (ETDEWEB)

    Alves, S; Kuhl, A; Najjar, F; Tringe, J; McMichael, L; Glascoe, L

    2012-02-03

    Many explosives will release additional energy after detonation as the detonation products mix with the ambient environment. This additional energy release, referred to as afterburn, is due to combustion of undetonated fuel with ambient oxygen. While the detonation energy release occurs on a time scale of microseconds, the afterburn energy release occurs on a time scale of milliseconds with a potentially varying energy release rate depending upon the local temperature and pressure. This afterburn energy release is not accounted for in typical equations of state, such as the Jones-Wilkins-Lee (JWL) model, used for modeling the detonation of explosives. Here we construct a straightforward and efficient approach, based on experiments and theory, to account for this additional energy release in a way that is tractable for large finite element fluid-structure problems. Barometric calorimeter experiments have been executed in both nitrogen and air environments to investigate the characteristics of afterburn for C-4 and other materials. These tests, which provide pressure time histories, along with theoretical and analytical solutions provide an engineering basis for modeling afterburn with numerical hydrocodes. It is toward this end that we have constructed a modified JWL equation of state to account for afterburn effects on the response of structures to blast. The modified equation of state includes a two phase afterburn energy release to represent variations in the energy release rate and an afterburn energy cutoff to account for partial reaction of the undetonated fuel.

  4. MUSIC with the UrQMD Afterburner

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Sangwook; Jeon, Sangyong; Gale, Charles [McGill University, Montreal, QC (Canada); Schenke, Björn [Brookhaven National Laboratory, Upton, NY (United States); Young, Clint [McGill University, Montreal, QC (Canada); University of Minnesota, Minneaplis, MN (United States)

    2013-05-02

    As RHIC is entering the precision measurement era and the LHC is producing a copious amount of new data, the role of 3+1D event-by-event viscous hydrodynamics is more important than ever to understand the bulk data as well as providing the background for hard probes. For more meaningful comparison with the experimental data, it is also important that hydrodynamics be coupled to the hadronic afterburner. In this proceeding we report on preliminary results of coupling MUSIC with UrQMD.

  5. MUSIC with the UrQMD Afterburner

    International Nuclear Information System (INIS)

    As RHIC is entering the precision measurement era and the LHC is producing a copious amount of new data, the role of 3+1D event-by-event viscous hydrodynamics is more important than ever to understand the bulk data as well as providing the background for hard probes. For more meaningful comparison with the experimental data, it is also important that hydrodynamics be coupled to the hadronic afterburner. In this proceeding we report on preliminary results of coupling MUSIC with UrQMD

  6. MUSIC with the UrQMD Afterburner

    Science.gov (United States)

    Ryu, Sangwook; Jeon, Sangyong; Gale, Charles; Schenke, Björn; Young, Clint

    2013-05-01

    As RHIC is entering the precision measurement era and the LHC is producing a copious amount of new data, the role of 3+1D event-by-event viscous hydrodynamics is more important than ever to understand the bulk data as well as providing the background for hard probes. For more meaningful comparison with the experimental data, it is also important that hydrodynamics be coupled to the hadronic afterburner. In this proceeding we report on preliminary results of coupling MUSIC with UrQMD.

  7. MUSIC with the UrQMD Afterburner

    OpenAIRE

    Ryu, Sangwook; Jeon, Sangyong; Gale, Charles; Schenke, Bjoern; Young, Clint

    2012-01-01

    As RHIC is entering the precision measurement era and the LHC is producing a copious amount of new data, the role of 3+1D event-by-event viscous hydrodynamics is more important than ever to understand the bulk data as well as providing the background for hard probes. For more meaningful comparison with the experimental data, it is also important that hydrodynamics be coupled to the hadronic afterburner. In this proceeding we report on preliminary results of coupling MUSIC with UrQMD.

  8. Numerical models for afterburning of TNT detonation products in air

    Science.gov (United States)

    Donahue, L.; Zhang, F.; Ripley, R. C.

    2013-11-01

    Afterburning occurs when fuel-rich explosive detonation products react with oxygen in the surrounding atmosphere. This energy release can further contribute to the air blast, resulting in a more severe explosion hazard particularly in confined scenarios. The primary objective of this study was to investigate the influence of the products equation of state (EOS) on the prediction of the efficiency of trinitrotoluene (TNT) afterburning and the times of arrival of reverberating shock waves in a closed chamber. A new EOS is proposed, denoted the Afterburning (AB) EOS. This EOS employs the JWL EOS in the high pressure regime, transitioning to a Variable-Gamma (VG) EOS at lower pressures. Simulations of three TNT charges suspended in a explosion chamber were performed. When compared to numerical results using existing methods, it was determined that the Afterburning EOS delays the shock arrival times giving better agreement with the experimental measurements in the early to mid time. In the late time, the Afterburning EOS roughly halved the error between the experimental measurements and results obtained using existing methods. Use of the Afterburning EOS for products with the Variable-Gamma EOS for the surrounding air further significantly improved results, both in the transient solution and the quasi-static pressure. This final combination of EOS and mixture model is recommended for future studies involving afterburning explosives, particularly those in partial and full confinement.

  9. Exergetic analysis of an aircraft turbojet engine with an afterburner

    Directory of Open Access Journals (Sweden)

    Ehyaei M.A.

    2013-01-01

    Full Text Available An exergy analysis is reported of a J85-GE-21 turbojet engine and its components for two altitudes: sea level and 11,000 meters. The turbojet engine with afterburning operates on the Brayton cycle and includes six main parts: diffuser, compressor, combustion chamber, turbine, afterburner and nozzle. Aircraft data are utilized in the analysis with simulation data. The highest component exergy efficiency at sea level is observed to be for the compressor, at 96.7%, followed by the nozzle and turbine with exergy efficiencies of 93.7 and 92.3%, respectively. At both considered heights, reducing of engine intake air speed leads to a reduction in the exergy efficiencies of all engine components and overall engine. The exergy efficiency of the turbojet engine is found to decrease by 0.45% for every 1°C increase in inlet air temperature.

  10. A method for aircraft afterburner combustion without flameholders

    Science.gov (United States)

    Birmaher, Shai

    2009-12-01

    State of the art aircraft afterburners employ spray bars to inject fuel and flameholders to stabilize the combustion process. Such afterburner designs significantly increase the length (and thus weight), pressure losses, and observability of the engine. This thesis presents a feasibility study of a compact 'prime and trigger' (PAT) afterburner concept that eliminates the fuel spray bars and flameholders and, thus, eliminates the above-mentioned problems. In this concept, afterburner fuel is injected just upstream or in between the turbine stages. As the fuel travels through the turbine stages, it evaporates, mixes with the bulk flow, and undergoes some chemical reactions without any significant heat release, a process referred to as 'priming'. Downstream of the turbine stages, combustion could take place through autoignition. However, if fuel autoignition does not occur or if autoignition does not produce a combustion zone that is stable and highly efficient, then a low power pilot, or 'trigger', can be used to control the combustion process. The envisioned trigger for the PAT concept is a jet of product gas from ultra-rich hydrocarbon/air combustion that is injected through the afterburner liner. This 'partial oxidation' (POx) gas, which consists mostly of H2, CO, and diluents, rapidly produces radicals and heat that accelerate the autoignition of the primed mixture and, thus, provide an anchor point for the afterburner combustion process. The objective of this research was to demonstrate the feasibility of the PAT concept by showing that (1) combustion of fuel injected within or upstream of turbine stages can occur only downstream of the turbine stages, and (2) the combustion zone is compact, stable and efficient. This was accomplished using two experimental facilities, a developed theoretical model, and Chemkin simulations. The first facility, termed the Afterburner Facility (AF), simulated the bulk flow temperature, velocity and O2 content through a turbojet

  11. Noise of high-performance aircraft at afterburner

    Science.gov (United States)

    Tam, Christopher K. W.; Parrish, Sarah A.

    2015-09-01

    The noise from a high-performance aircraft at afterburner is investigated. The main objective is to determine whether the dominant noise components are the same or similar to those of a hot supersonic laboratory jet. For this purpose, measured noise data from F-22A Raptors are analyzed. It is found, based on both spectral and directivity data, that there is a new dominant noise component in addition to the usual turbulent mixing noise. The characteristic features of the new noise component are identified. Measured data indicates that the new noise component is observed only when the rate of fuel burn of the engine is increased significantly above that of the intermediate power setting. This suggests that the new noise component is combustion related. The possibility that it is indirect combustion noise generated by the passage of hot spots from the afterburner through the nozzle of the jet is investigated. Because flow and temperature data were not measured in the F-22A engine tests, to provide support to the proposition, numerical simulations of indirect combustion noise generation due to the passing of an entropy wave pulse (a hot spot) through a military-style nozzle are carried out. Sound generation is observed at the front and at the back of the pulse. This creates a fast and a slow acoustic wave as the sound radiates out from the nozzle exit. Quantitative estimates of the principal directions of acoustic radiation due to the emitted fast and slow acoustic waves are made. It is found that there are reasonably good agreements with measured data. To estimate the intensity level (IL) of the radiated indirect combustion noise, a time-periodic entropy wave train of 15 percent temperature fluctuation is used as a model of the hot spots coming out of the afterburner. This yields an IL of 175.5 dB. This is a fairly intense noise source, well capable of causing the radiation of the new jet noise component.

  12. Heavy ion acceleration in the Breakout Afterburner regime

    CERN Document Server

    Petrov, G M; Thomas, A G R; Krushelnick, K; Beg, F N

    2015-01-01

    Theoretical study of heavy ion acceleration from an ultrathin (20 nm) gold foil irradiated by sub-picosecond lasers is presented. Using two dimensional particle-in-cell simulations we identified two highly efficient ion acceleration schemes. By varying the laser pulse duration we observed a transition from Radiation Pressure Acceleration to the Breakout Afterburner regime akin to light ions. The underlying physics and ion acceleration regimes are similar to that of light ions, however, nuances of the acceleration process make the acceleration of heavy ions more challenging. Two laser systems are studied in detail: the Texas Petawatt Laser and the Trident laser, the former having pulse duration 180 fs, intermediate between very short femtosecond pulses and picosecond pulses. Both laser systems generated directional gold ions beams (~10 degrees half-angle) with fluxes in excess of 1011 ion/sr and normalized energy >10 MeV/nucleon.

  13. Measurement of Afterburning Effect of Underoxidized Explosives by Underwater Explosion Method

    Science.gov (United States)

    Cao, Wei; He, Zhongqi; Chen, Wanghua

    2015-04-01

    The afterburning effect of TNT and a desensitized hexogen RDX-Al explosive was studied in a defined gas volume under water. A double-layer container (DLC) filled with different gases (air, oxygen, and nitrogen) was used to control and distinguish the afterburning effect of explosives. After the charges in the DLC were initiated under water, the shock wave signals were collected and analyzed. It is shown that shock wave peak pressures are duly in compliance with explosion similarity law, pressure, and impulse histories for explosions in oxygen and air are greater than those recorded for explosions in nitrogen due to the afterburing reaction. Moreover, the afterburning energy was calculated. Results show that even though there is excess oxygen in the gas volume, the afterburning energy may not reach the theoretically maximum value. This result is different from that in confined explosion, where the presence of excess oxygen in the compressed gas filling a bomb leads to complete combustion of the detonation products.

  14. Improving the Efficiency of an Ideal Heat Engine: The Quantum Afterburner

    OpenAIRE

    Scully, Marlan O.

    2001-01-01

    By using a laser and maser in tandem, it is possible to obtain laser action in the hot exhaust gases involved in heat engine operation. Such a "quantum afterburner" involves the internal quantum states of working gas atoms or molecules as well as the techniques of cavity quantum electrodynamics and is therefore in the domain of quantum thermodynamics. As an example, it is shown that Otto cycle engine performance can be improved beyond that of the "ideal" Otto heat engine.

  15. Integrated pneumatic transporter-incinerator-afterburner subsystem development. [for spacecraft waste disposal

    Science.gov (United States)

    Manning, J. R.

    1974-01-01

    The design and fabrication of a prototype automatic transport system to move wastes to an incinerator onboard a spacecraft are described. The commode and debris collector, subsystems to treat noncondensible gases, oxygen supply to incinerator and afterburner, and removal and ash collection from the incinerator are considered, as well as a zero gravity condenser. In-depth performance testing of a totally integrated incineration system and autoclaving as a waste treatment method are included.

  16. Turbulent Mixing and Afterburn in Post-Detonation Flow with Dense Particle Clouds

    Science.gov (United States)

    Menon, Suresh

    2015-06-01

    Reactive metal particles are used as additives in most explosives to enhance afterburn and augment the impact of the explosive. The afterburn is highly dependent on the particle dispersal and mixing in the post-detonation flow. The post-detonation flow is generally characterized by hydrodynamic instabilities emanating from the interaction of the blast waves with the detonation product gases and the ambient air. Further, influenced by the particles, the flow evolves and develops turbulent structures, which play vital role in determining mixing and combustion. Past studies in the field in open literature are reviewed along with some recent studies conducted using three dimensional numerical simulations of particle dispersal and combustion in the post-detonation flow. Spherical nitromethane charges enveloped by particle shells of varying thickness are considered along with dense loading effects. In dense flows, the particles block the flow of the gases and therefore, the role of the inter-particle interactions on particle dispersal cannot be ignored. Thus, both dense and dilute effects must be modeled simultaneously to simulate the post-detonation flow. A hybrid equation of state is employed to study the evolution of flow from detonation initiation till the late time mixing and afterburn. The particle dispersal pattern in each case is compared with the available experimental results. The burn rate and the energy release in each case is quantified and the effect of total mass of the particles and the particle size is analyzed in detail. Strengths and limitations of the various methods used for such studies as well as the uncertainties in the modeling strategies are also highlighted. Supported by Defense Threat Reduction Agency.

  17. A computer simulation of the afterburning processes occurring within solid rocket motor plumes in the troposphere

    Science.gov (United States)

    Gomberg, R. I.; Stewart, R. B.

    1976-01-01

    As part of a continuing study of the environmental effects of solid rocket motor (SRM) operations in the troposphere, a numerical model was used to simulate the afterburning processes occurring in solid rocket motor plumes and to predict the quantities of potentially harmful chemical species which are created. The calculations include the effects of finite-rate chemistry and turbulent mixing. It is found that the amount of NO produced is much less than the amount of HCl present in the plume, that chlorine will appear predominantly in the form of HCl although some molecular chlorine is present, and that combustion is complete as is evident from the predominance of carbon dioxide over carbon monoxide.

  18. Preliminary Transient Performance Data for Afterburner Operation of Westinghouse Electronic Power Regulator on XJ34-WE-32 Turbojet Engine in Altitude Wind Tunnel

    Science.gov (United States)

    Vasu, George; Schwent, Glennon V.; Ketchum, James R.

    1951-01-01

    At the request of the Bureau of Aeronautics, Department of the Navy, an investigation of the Westinghouse XJ34-WE-32 turbojet engine is being conducted in the NACA Lewis altitude wind tunnel to determine the steady-state and transient operating characteristics of the controlled and uncontrolled engine at various altitudes and ram pressure ratios. As part of this program, transient performance data that illustrate the operation of the engine is obtained in the form of oscillographic traces. Similar data for engine operation i n the afterburning range, covering a range of throttle settings from the minimum value giving rated speed (throttle position, 72 degrees) to full afterburning (throttle position, ll0 degrees), is presented herein. These data thus serve to indicate the transient characteristics of the engine when the throttle is advance into, withdrawn from, and moved within the afterburning range in a stepwise manner, as well as the steady-state stability of the engine during afterburning .

  19. Polynuclear aromatic hydrocarbon and particulate emissions from two-stage combustion of polystyrene: the effects of the secondary furnace (afterburner) temperature and soot filtration.

    Science.gov (United States)

    Wang, Jun; Richter, Henning; Howard, Jack B; Levendis, Yiannis A; Carlson, Joel

    2002-02-15

    Laboratory experiments were conducted in a two-stage horizontal muffle furnace in order to monitor emissions from batch combustion of polystyrene (PS) and identify conditions that minimize them. PS is a dominant component of municipal and hospital waste streams. Bench-scale combustion of small samples (0.5 g) of shredded styrofoam cups was conducted in air, using an electrically heated horizontal muffle furnace, kept at Tgas = 1000 degrees C. Upon devolatilization, combustion of the polymer took place in a diffusion flame over the sample. The gaseous combustion products were mixed with additional air in a venturi and were channeled to a secondary muffle furnace (afterburner) kept at Tgas = 900-1100 degrees C; residence time therein varied between 0.6 and 0.8 s. At the exits of the primary and the secondary furnace the emissions of CO, CO2, O2, NOx, particulates as well as volatile and semivolatile hydrocarbons, such as polycyclic aromatic hydrocarbons (PAH), were monitored. Online analyzers, gravimetric techniques, and gas chromatography coupled to mass spectrometry (GC-MS) were used. Experiments were also conducted with a high-temperature barrier filter, placed just before the exit of the primary furnace to prevent the particulates from entering into the secondary furnace. Results demonstrated the beneficial effect of the afterburner in reducing PAH concentrations, including those of mutagenic species such as benzo[a]pyrene. Concentrations of individual PAH exhibited a pronounced after burner temperature dependence, typically ranging from a small decrease at 900 degrees C to a larger degree of consumption at 1100 degrees C. Consumption of PAH was observed to be the dominant feature at 900 degrees C, while significant quantities of benzene and some of its derivatives, captured by means of carbosieve/Carbotrap adsorbents, were formed in the afterburner at a temperature of 1000 degrees C. In the primary furnace, about 30% of the mass of the initial polystyrene was

  20. Surface Temperature Measurements from a Stator Vane Doublet in a Turbine Engine Afterburner Flame Using a YAG:Tm Thermographic Phosphor

    Science.gov (United States)

    Eldridge, J. I.; Walker, D. G.; Gollub, S. L.; Jenkins, T. P.; Allison, S. W.

    2015-01-01

    Luminescence-based surface temperature measurements were obtained from a YAG:Tm-coated stator vane doublet exposed to the afterburner flame of a J85 test engine at University of Tennessee Space Institute (UTSI). The objective of the testing was to demonstrate that reliable surface temperatures based on luminescence decay of a thermographic phosphor producing short-wavelength emission could be obtained from the surface of an actual engine component in a high gas velocity, highly radiative afterburner flame environment. YAG:Tm was selected as the thermographic phosphor for its blue emission at 456 nm (1D23F4 transition) and UV emission at 365 nm (1D23H6 transition) because background thermal radiation is lower at these wavelengths, which are shorter than those of many previously used thermographic phosphors. Luminescence decay measurements were acquired using a probe designed to operate in the afterburner flame environment. The probe was mounted on the sidewall of a high-pressure turbine vane doublet from a Honeywell TECH7000 turbine engine coated with a standard electron-beam physical vapor deposited (EB-PVD) 200-m-thick TBC composed of yttria-stabilized zirconia (YSZ) onto which a 25-m-thick YAG:Tm thermographic phosphor layer was deposited by solution precursor plasma spray (SPPS). Spot temperature measurements were obtained by measuring luminescence decay times at different afterburner power settings and then converting decay time to temperature via calibration curves. Temperature measurements using the decays of the 456 and 365 nm emissions are compared. While successful afterburner environment measurements were obtained to about 1300C with the 456 nm emission, successful temperature measurements using the 365 nm emission were limited to about 1100C due to interference by autofluorescence of probe optics at short decay times.

  1. Combustion control of a wood burning stove with afterburner. Final report; Verbrennungsregelung an einer Stueckholzfeuerung fuer Ofensetzer. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Chiquet, C. [Unes Handels AG, Ormalingen (Switzerland)

    1996-11-15

    For the oven building trade, an electronic controller was adapted for wood burning stoves with afterburners, to regulate burn rate and emissions output. The controller utilizes Fuzzy-Technology to reduce emissions and optimize burning efficiency. The controller also offers a significant improvement in operating ease and safety. The rate of burning can be reduced to 50% of full capacity, therefore allowing 35 kg of wood to burn safely for nine hours without additional supervision. Additionally, the CO-emissions remain below 500 mg/Nm{sup 3} during the stationary burning phase. This new technology allows the oven builder to construct ovens with large enough fuel capacities, for use in conjunction with heat exchangers, to heat whole houses and buildings. With simpler operation and increased safety, this controller can further the functionality and popularity of wood burning energy systems. (author) figs., tabs.

  2. Helium-3 production from Pb+Pb collisions at SPS energies with the UrQMD model and the traditional coalescence afterburner

    CERN Document Server

    Li, Qingfeng; Wang, Xiaobao; Shen, Caiwan

    2016-01-01

    A potential version of the UrQMD (UrQMD/M) transport model and a traditional coalescence model are combined to calculate the production of $^3$He fragments in central Pb+Pb collisions at SPS energies 20-80 GeV/nucleon. It is found that the Lorentz transformation in the afterburner influences visibly the $^3$He yield and should be considered in calculations. The rapidity distribution of $^3$He multiplicities (including the concave shape) can be described well with UrQMD/M when it stops during t$_{\\rm cut}$=100$\\pm$25 fm$/c$ and the coalescence afterburner with one parameter set of ($R_0$,$P_0$)=(3.8 fm, 0.3 GeV$/$c) is taken into use afterwards.

  3. Rapidity distribution of protons from the potential version of UrQMD model and the traditional coalescence afterburner

    CERN Document Server

    Li, Qingfeng; Wang, Xiaobao; Shen, Caiwan

    2016-01-01

    Rapidity distributions of both E895 proton data at AGS energies and NA49 net proton data at SPS energies can be described reasonably well with a potential version of the UrQMD in which mean-field potentials for both pre-formed hadrons and confined baryons are considered, with the help of a traditional coalescence afterburner in which one parameter set for both relative distance $R_0$ and relative momentum $P_0$, (3.8 fm, 0.3 GeV$/$c), is used. Because of the large cancellation between the expansion in $R_0$ and the shrinkage in $P_0$ through the Lorentz transformation, the relativistic effect in clusters has little effect on the rapidity distribution of free (net) protons. Using a Woods-Saxon-like function instead of a pure logarithmic function as seen by FOPI collaboration at SIS energies, one can fit well both the data at SIS energies and the UrQMD calculation results at AGS and SPS energies. Further, it is found that for central Au+Au or Pb+Pb collisions at top SIS, SPS and RHIC energies, the proton fracti...

  4. Rapidity distribution of protons from the potential version of UrQMD model and the traditional coalescence afterburner

    Science.gov (United States)

    Li, QingFeng; Wang, YongJia; Wang, XiaoBao; Shen, CaiWan

    2016-02-01

    Rapidity distributions of both E895 proton data at AGS energies and NA49 net proton data at SPS energies can be described reasonably well with a potential version of the UrQMD in which mean-field potentials for both pre-formed hadrons and confined baryons are considered, with the help of a traditional coalescence afterburner in which one parameter set for both relative distance R 0 and relative momentum P 0, (3.8 fm, 0.3 GeV/ c), is used. Because of the large cancellation between the expansion in R 0 and the shrinkage in P 0 through the Lorentz transformation, the relativistic effect in clusters has little effect on the rapidity distribution of free (net) protons. Using a Woods-Saxon-like function instead of a pure logarithmic function as seen by FOPI collaboration at SIS energies, one can fit well both the data at SIS energies and the UrQMD calculation results at AGS and SPS energies. Further, it is found that for central Au+Au or Pb+Pb collisions at top SIS, SPS and RHIC energies, the proton fractions in clusters are about 33%, 10%, and 0.7%, respectively.

  5. Development of integrated, zero-G pneumatic transporter/rotating paddle incinerator/catalytic afterburner subsystem for processing human wastes on board spacecraft

    Science.gov (United States)

    Fields, S. F.; Labak, L. J.; Honegger, R. J.

    1974-01-01

    A four component system was developed which consists of a particle size reduction mechanism, a pneumatic waste transport system, a rotating-paddle incinerator, and a catalytic afterburner to be integrated into a six-man, zero-g subsystem for processing human wastes on board spacecraft. The study included the development of different concepts or functions, the establishment of operational specifications, and a critical evaluation for each of the four components. A series of laboratory tests was run, and a baseline subsystem design was established. An operational specification was also written in preparation for detailed design and testing of this baseline subsystem.

  6. Position Proportional the Afterburner Compensation Electric Load Simulator Research%位置比例加力补偿电动负载模拟器的研究

    Institute of Scientific and Technical Information of China (English)

    顾文娟; 刘涛; 朱战霞; 孙力

    2013-01-01

    Through the servo loading system and the position synchronization afterburner compensate for load analysis,the proportion of a position to follow the force compensation loading system,and its MATLAB / SIMULINK modeling and simulation are presented.Finally,the position proportional follow the force compensating loading system simulation results,the results indicate that the system can effectively improve the system band.%通过对力伺服加载系统和位置同步加力补偿加载系统的分析,提出了一种位置比例跟随力补偿加载系统;并对其进行MATLAB/SIMULINK建模仿真.最后,对位置比例跟随力补偿加载系统的仿真结果进行了分析,结果说明该系统能够有效提高系统频带.

  7. Surface Temperature Measurements from a Stator Vane Doublet in a Turbine Engine Afterburner Flame using Ultra-Bright Cr-Doped GdAlO3 Thermographic Phosphor

    Science.gov (United States)

    Eldridge, Jeffrey I.; Jenkins, Thomas P.; Allison, Stephen W.; Wolfe, Douglas E.; Howard, Robert P.

    2013-01-01

    Luminescence-based surface temperature measurements from an ultra-bright Cr-doped GdAlO3 perovskite (GAP:Cr) coating were successfully conducted on an air-film-cooled stator vane doublet exposed to the afterburner flame of a J85 test engine at University of Tennessee Space Institute (UTSI). The objective of the testing at UTSI was to demonstrate that reliable thermal barrier coating (TBC) surface temperatures based on luminescence decay of a thermographic phosphor could be obtained from the surface of an actual engine component in an aggressive afterburner flame environment and to address the challenges of a highly radiant background and high velocity gases. A high-pressure turbine vane doublet from a Honeywell TECH7000 turbine engine was coated with a standard electron-beam physical vapor deposited (EB-PVD) 200-m-thick TBC composed of yttria-stabilized zirconia (YSZ) onto which a 25-m-thick GAP:Cr thermographic phosphor layer was deposited by EB-PVD. The ultra-bright broadband luminescence from the GAP:Cr thermographic phosphor is shown to offer the advantage of over an order-of-magnitude greater emission intensity compared to rare-earth-doped phosphors in the engine test environment. This higher emission intensity was shown to be very desirable for overcoming the necessarily restricted probe light collection solid angle and for achieving high signal-to-background levels. Luminescence-decay-based surface temperature measurements varied from 500 to over 1000C depending on engine operating conditions and level of air film cooling.

  8. "2001: A Space Odyssey" Revisited: The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners. Revised

    Science.gov (United States)

    Borowski, Stanley K.; Dudzinski, Leonard A.

    2001-01-01

    The prospects for "24 hour" commuter flights to the Moon. similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale. are examined using two near term. "high leverage" technologies-liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and "lunar-derived" oxygen (LUNOX) production. Iron-rich volcanic glass. or "orange soil," discovered during the Apollo 17 mission to Taurus-Littrow. has produced a 4% oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way. LANTR utilizes the large divergent section of its nozzle as an "afterburner" into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the engine's choked sonic throat-essentially "scramjet propulsion in reverse." By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that "big engine" performance can be obtained using smaller. more affordable. easier to test NTR engines. The use of high-density LOX in place of low-density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or "in-line" Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an "expendable mode" initially, to maximize delivered surface payload on each mission. The increased

  9. 2001: A Space Odyssey Revisited: The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners. Revised

    Science.gov (United States)

    Borowski, Stanley; Dudzinski, Leonard A.

    2003-01-01

    The prospects for 24 hour commuter flights to the Moon, similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale, are examined using two near term, high leverage technologies: liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and lunar-derived oxygen (LUNOX) production. Iron-rich volcanic glass, or orange soil, discovered during the Apollo 17 mission to Taurus-Littrow, has produced a 4 percent oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way. LANTR utilizes the large divergent section of its nozzle as an afterburner into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the engine's choked sonic throat, essentially scramjet propulsion in reverse. By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that big engine performance can be obtained using smaller, more affordable, easier to test NTR engines. The use of high-density LOX in place of low density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or in-line Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an expendable mode initially, to maximize delivered surface payload on each mission. The increased payload is

  10. "2001: A Space Odyssey" Revisited--The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners

    Science.gov (United States)

    Borowski, Stanley K.; Dudzinski, Leonard A.

    1998-01-01

    The prospects for "24 hour" commuter flights to the Moon, similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale, are examined using two near term, "high leverage" technologies--liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and "lunar-derived" oxygen (LUNOX) production. Ironrich volcanic glass, or "orange soil," discovered during the Apollo 17 mission to Taurus-Littrow, has produced a 4% oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way, LANTR utilizes the large divergent section of its nozzle as an "afterburner" into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging front the engine's choked sonic throat--essentially "scramjet propulsion in reverse." By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that "big engine" performance can be obtained using smaller, more affordable, easier to test NTR engines. The use of high-density LOX in place of low-density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or "in-line" Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an "expendable mode" initially, to maximize delivered surface payload on each mission. The increased

  11. Uso del Modelo Lineal de un Turboventilador al Análisis de su Funcionamiento con Poscombustión Application of the Turbofan Linear Model to the Analysis of its Functioning with Afterburner

    Directory of Open Access Journals (Sweden)

    Oleg A Khatchatourian

    2007-01-01

    Full Text Available El objetivo de este trabajo fue la comparación de eficacia de sistema de los sostenedores mecánicos y aerodinámicos de llama para el dispositivo de poscombustión de turboventilador. Se propone un modelo para comparar la eficacia de sistemas mecánicos y aerodinámicos de llama y se analiza la influencia de diversos parámetros en la eficacia. El sistema aerodinámico puede ser recomendado como unidad de aumento moderado de empuje para uso en operación de emergencia o en corto tiempo de operación.The purpose of the presented work was a comparison of an efficiency of Mechanical Flame Holders system and Aerodynamic Flame Holders system for turbofan engine afterburner. The linear mathema-tical model of the turbofan engine was developed to analyze an influence of air compressor-bleeding for Aerodynamic Flame Holders system on the turbofan engine characteristics. An evaluation criterion was proposed to compare an efficiency of Mechanical and Aerodynamic systems. An influence of dif-ferrent parameters on this criterion was analyzed. The factors that cause pressure loss accretion during afterburner down-time, increase the region where the use of Aerodynamic Flame Holders system is preferable in comparison with Mechanical Flame Holders system. It may be concluded that this system can be recommended as moderate thrust augmentation reserve unit for use in emergency operation (insufficient take-off distance, engine failure or in short- time operation (to break the sound barrier, to reach the most height, take-off.

  12. Fuel property effects on USAF gas turbine engine combustors and afterburners

    Science.gov (United States)

    Reeves, C. M.

    1984-01-01

    Since the early 1970s, the cost and availability of aircraft fuel have changed drastically. These problems prompted a program to evaluate the effects of broadened specification fuels on current and future aircraft engine combustors employed by the USAF. Phase 1 of this program was to test a set of fuels having a broad range of chemical and physical properties in a select group of gas turbine engine combustors currently in use by the USAF. The fuels ranged from JP4 to Diesel Fuel number two (DF2) with hydrogen content ranging from 14.5 percent down to 12 percent by weight, density ranging from 752 kg/sq m to 837 kg/sq m, and viscosity ranging from 0.830 sq mm/s to 3.245 sq mm/s. In addition, there was a broad range of aromatic content and physical properties attained by using Gulf Mineral Seal Oil, Xylene Bottoms, and 2040 Solvent as blending agents in JP4, JP5, JP8, and DF2. The objective of Phase 2 was to develop simple correlations and models of fuel effects on combustor performance and durability. The major variables of concern were fuel chemical and physical properties, combustor design factors, and combustor operating conditions.

  13. A Study on Emissions from Afterburning Chambers Included in Metallurgical Thermal Equipment

    Directory of Open Access Journals (Sweden)

    Gil S.

    2014-06-01

    Full Text Available Przedstawiono badania eksploatacyjne komór dopalania w hutniczych urządzeniach cieplnych. Przeanalizowano wpływ temperatury i działań modernizacyjnych w układzie opalania na stężenie tlenków azotu i tlenku węgla. Dla zapewnienia skuteczności dopalania gazów z procesów technologicznych i minimalizacji stężenia CO, należy zwiększyć temperaturę w komorze dopalania do ok. 1053-1973 K, przy zapewnieniu wyrównanego rozkładu temperatury w płomieniu. Może to spowodować nieznaczne podwyższenie stężenia NOx o ok. 20 mg/m3n.

  14. Cruising in afterburner: Air force fuel use and emerging energy policy

    International Nuclear Information System (INIS)

    Operational and mission efficiency were estimated for Air Force fighters, bombers and transports from fuel use data from 2001 through 2008 as reported in the Air Force Total Cost of Ownership (AFTOC) database. This analysis estimated efficiency in terms of the best performance theoretically possible for each platform based upon the energy available in the fuel expended. Operational efficiency considered aircraft operations in general, without regard for the type of mission. Mission efficiency only considered use of allocated fuel for combat (non-training) sorties. The cost associated with fuel inefficiency of the combined fighter, bomber and tanker force were estimated based on the fiscal year 2008 costs of fuel, fully burdened to include the cost of aerial refueling. The total cost of operational inefficiency was estimated at $5 billion per year. The fully burdened cost of mission inefficiency added an additional $3.6 billion for a total per year cost estimate of $8.6 billion. This represents 21.5% of the $40 billion portion of the 2009 budget dedicated to modernization. A business case for force-structure change is presented, which describes how these cost savings can be leveraged for modernization. - Highlights: → I assess how efficiently the United States Air Force uses fuel for aviation. → I estimate the cost associated with fuel inefficiency. → Improved technology can dramatically improve fuel efficiency. → There is potentially a large cost savings associated with improved fuel efficiency. → I present a business case to leverage this cost savings for modernization.

  15. A Study on Emissions from Afterburning Chambers Included in Metallurgical Thermal Equipment

    OpenAIRE

    Gil S.; Rozpondek M.; Bialik W.

    2014-01-01

    Przedstawiono badania eksploatacyjne komór dopalania w hutniczych urządzeniach cieplnych. Przeanalizowano wpływ temperatury i działań modernizacyjnych w układzie opalania na stężenie tlenków azotu i tlenku węgla. Dla zapewnienia skuteczności dopalania gazów z procesów technologicznych i minimalizacji stężenia CO, należy zwiększyć temperaturę w komorze dopalania do ok. 1053-1973 K, przy zapewnieniu wyrównanego rozkładu temperatury w płomieniu. Może to spowodować nieznaczne podwyższenie stężeni...

  16. Modeling of Chemical Reactions in Afterburning for the Reduction of N2O

    DEFF Research Database (Denmark)

    Gustavsson, Lennart; Glarborg, Peter; Leckner, Bo

    1996-01-01

    Full scale tests in a 12 MW fluidized bed combustor on reduction of N2O by secondary fuel injection are analyzed in terms a model that involves a detailed reaction mechanism for the gas phase chemistry as well as a description of gas-solid reactions.......Full scale tests in a 12 MW fluidized bed combustor on reduction of N2O by secondary fuel injection are analyzed in terms a model that involves a detailed reaction mechanism for the gas phase chemistry as well as a description of gas-solid reactions....

  17. Development of an integrated, zero-G pneumatic transporter/rotating-paddle incinerator/catalytic afterburner subsystem for processing human waste on board spacecraft

    Science.gov (United States)

    Fields, S. F.; Labak, L. J.; Honegger, R. J.

    1974-01-01

    A baseline laboratory prototype of an integrated, six man, zero-g subsystem for processing human wastes onboard spacecraft was investigated, and included the development of an operational specification for the baseline subsystem, followed by design and fabrication. The program was concluded by performing a series of six tests over a period of two weeks to evaluate the performance of the subsystem. The results of the tests were satisfactory, however, several changes in the design of the subsystem are required before completely satisfactory performance can be achieved.

  18. Between designer drugs and afterburners: A Lexicographic-Semantic Study of Equivalence Tussen designer drugs (ontwerpersdwelms en afterburners (naverbranders: 'n leksikografies-semantiese studie van ekwivalensie.

    Directory of Open Access Journals (Sweden)

    Arleta Adamska-Sałaciak

    2012-01-01

    Full Text Available

    The lexicons of natural languages are not isomorphic. Reasons for the anisomorphism can be sought on three interrelated planes: language structure, extralinguistic reality, and conceptualisation. Simply put, the relevant differences may reside in the language, the world, the mind, or any combination of these. As a result, what goes under the name of lexicographic equivalence is a rather heterogeneous category. Growing awareness of this fact has resulted over the years in the creation of several tentative typologies of equivalence, one of which is presented below, together with a brief discussion of some strategies for dealing with imperfect equivalence.

    The remaining part of the article comprises a detailed analysis of a single problem encountered while preparing a new edition of a bilingual dictionary for Polish learners of English. The task at hand involved choosing a viable counterpart for a (Polish semantic neologism from among a few (English equivalence candidates. In the discussion, reference is made both to the metalexicographic categories introduced earlier and to such concepts developed by lexical (especially cognitive semantics which may prove helpful in capturing the meaning differences between the source-language item and its competing target-language renditions.

    This micro-scale dissection of a single specimen demonstrates that we are still some way from being able to classify, let alone deal with, all the instances of imperfect interlingual correspondence that come our way. Persisting in the efforts to advance our understanding of the complex issues covered by the blanket term lexicographic equivalence thus seems crucial for improving the treatment of meaning in bilingual dictionaries.

    Die leksikons van natuurlike tale is nie isomorf nie. Redes vir die gebrek aan isomorfie kom op drie onderling verwante vlakke voor: taalstruktuur, die buitetalige realiteit, en konseptualisasie. Anders gestel kan die tersaaklike verskille in die taal, die wêreld, die verstand, of enige kombinasie hiervan aangetref word. Gevolglik is dit wat as leksikografiese ekwivalensie bekend staan 'n nogal heterogene kategorie. 'n Groeiende bewuswording van hierdie feit het oor die jare daartoe gelei dat verskeie tentatiewe tipologieë van ekwivalensie geskep is, waarvan een hieronder aangebied word, saam met 'n kort bespreking van sommige strategieë om onvolledige ekwivalensie te hanteer.

    Die oorblywende deel van die artikel bevat 'n uitvoerige ontleding van 'n enkele probleem wat teëgekom is toe 'n nuwe uitgawe van 'n tweetalige woordeboek vir Poolse aanleerders van Engels saamgestel is. Die betrokke taak het behels dat 'n lewensvatbare teenhanger vir 'n (Poolse semantiese neologisme uit 'n paar ekwivalente (Engelse alternatiewe gekies word. In die bespreking word verwys na sowel die metaleksikografiese kategorieë wat vroeër geopper is, as na konsepte in die leksikale (veral die kognitiewe semantiek wat sou kon help om die betekenisverskil tussen die brontaalitem en sy kompeterende doeltaalvertalings vas te vang.

    Hierdie ontleding van 'n enkele voorbeeld op mikroskaal demonstreer dat ons nog ver daarvan is om al die gevalle van onvolledige intertalige ooreenstemming wat ons teëkom te kan klassifiseer, wat nog te sê van te hanteer. Om vol te hou met ons pogings om die komplekse vraagstukke te verstaan wat deur die oorkoepelende term leksikografiese ekwivalensie gedek word, is dit dus uiters belangrik om die hantering van betekenis in tweetalige woordeboeke te verbeter.

  19. Application of Filled Function Method to Specific Fuel Consumption Mode Control for Aeroengines in Afterburning Condition%填充函数法在发动机加力最小油耗模式控制中的应用

    Institute of Scientific and Technical Information of China (English)

    张海波; 孙健国

    2010-01-01

    主要研究了航空发动机性能寻优控制(PSC)算法问题.提出一种用于解决非线性约束优化问题的基于填充函数方法(FFM)的实时优化控制策略.通过构造填充函数,该算法可以在优化计算过程中能够不断跳出局部最优点,使得算法本身具备了全局寻优能力.详细介绍了其算法主要内容与实现途径,基于上述的填充函数优化算法,以某型涡扇发动机加力最小油耗优化控制模式为仿真算例,验证了该算法在解决航空发动机性能寻优控制问题时,相比传统的序列线性规划方法在全局寻优方面具有更好的效果.

  20. High-efficiency high-energy Ka source for the critically-required maximum illumination of x-ray optics on Z using Z-petawatt-driven laser-breakout-afterburner accelerated ultrarelativistic electrons LDRD .

    Energy Technology Data Exchange (ETDEWEB)

    Sefkow, Adam B.; Bennett, Guy R.

    2010-09-01

    Under the auspices of the Science of Extreme Environments LDRD program, a <2 year theoretical- and computational-physics study was performed (LDRD Project 130805) by Guy R Bennett (formally in Center-01600) and Adam B. Sefkow (Center-01600): To investigate novel target designs by which a short-pulse, PW-class beam could create a brighter K{alpha} x-ray source than by simple, direct-laser-irradiation of a flat foil; Direct-Foil-Irradiation (DFI). The computational studies - which are still ongoing at this writing - were performed primarily on the RedStorm supercomputer at Sandia National Laboratories Albuquerque site. The motivation for a higher efficiency K{alpha} emitter was very clear: as the backlighter flux for any x-ray imaging technique on the Z accelerator increases, the signal-to-noise and signal-to-background ratios improve. This ultimately allows the imaging system to reach its full quantitative potential as a diagnostic. Depending on the particular application/experiment this would imply, for example, that the system would have reached its full design spatial resolution and thus the capability to see features that might otherwise be indiscernible with a traditional DFI-like x-ray source. This LDRD began FY09 and ended FY10.

  1. Design and testing of a combustor for a turbo-ramjet for UAV and missile applications

    OpenAIRE

    Piper, Ross H.

    2003-01-01

    Approved for public release, distribution unlimited An existing freejet facility was upgraded and its range of operation extended into the high subsonic regime for operation as a test rig for the development of a combined-cycle, turbo-ramjet engine. A combustor was designed, developed, and tested as the afterburner for the turbo-ramjet engine. At subsonic speeds with the afterburner running, an increase in thrust of 40% was measured over the baseline turbojet running at 80% spool speed. A ...

  2. The energetic performance of a novel hybrid solar thermal and chemical looping combustion plant

    International Nuclear Information System (INIS)

    Highlights: • A hybrid solar chemical looping combustion power cycle is reported. • The cycle is studied for two configurations, with and without an after-burner. • The oxygen carrier particles are used as storage medium for solar thermal energy. • Total solar shares of 41.4% and 60% are achieved with and without the after-burner. • Efficiencies of 50% and 44.0% are achieved with and without the after-burner. - Abstract: The overall energetic performance of a gas turbine combined cycle powered by a hybrid cycle between a solar thermal and a chemical looping combustion (CLC) system firing methane is reported for two configurations. In one case, the outlet from the air reactor is fed directly to a gas turbine, while in the other an after-burner, also firing methane, is added to increase the gas turbine inlet temperature. The cycle is simulated using Aspen Plus software for the average diurnal profile of normal irradiance for Port Augusta, South Australia. The first law efficiency, total solar absorption efficiency, average and peak fractional power boosts, total solar share, net solar to electrical efficiency, fraction of pressurised CO2, incremental CO2 avoidance and the exergy efficiency for both cycles are reported. The calculations predict a first law efficiency of 50.0% for the cycle employing an after-burner, compared with 44.0% for that without the after-burner. However, this is achieved at the cost of decreasing the solar share from 60.0%, without the after-burner, to 41.4% with it. Also reported is the sensitivity analysis of performance to variations in key operating parameters. The sensitivity analysis shows that further improvements to the performance of the cycle are possible

  3. Tentative design of beam focusing for the AHF linac and transport systems

    International Nuclear Information System (INIS)

    Proposals for an advanced hadron facility include building afterburner linacs for LAMPF. A first afterburner, Add-on Linac number 1, is proposed to accelerate the beam from 0.8 to 1.6 GeV. The output beam would then be fed to a compressor ring and to another afterburner, Add-on Linac number 2. We make a rough estimate of the transverse focusing strength needed in these linacs, and consider the transport line from the end of the LAMPF 805-MHz linac to the start of Add-on Linac number 1. A rebuncher is needed in this transport line for proper acceptance of the beam into the add-on linac. 2 refs., 4 figs

  4. Termická oxidace oxidu uhelnatého ve spalných plynech

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Trnka, Otakar; Veselý, Václav; Svoboda, Karel

    2011-01-01

    Roč. 105, č. 7 (2011), s. 546-552. ISSN 0009-2770 R&D Projects: GA AV ČR IAA400720701 Institutional research plan: CEZ:AV0Z40720504 Keywords : carbon monoxide * rate of oxidation * afterburner design Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.529, year: 2011

  5. 40 CFR Table 2 to Subpart Rrr of... - Summary of Operating Requirements for New and Existing Affected Sources and Emission Units

    Science.gov (United States)

    2010-07-01

    ... scrap dryer/delacquering kiln/decoating kiln Labeling Identification, operating parameter ranges and... residence time requirements posted at scrap dryer/delacquering kiln/decoating kiln. Aluminum scrap shredder... VE and complete in accordance with the OM&M plan. b Thermal chip dryer with afterburner...

  6. 30 CFR 7.302 - Definitions.

    Science.gov (United States)

    2010-07-01

    ... MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Electric Motor Assemblies § 7.302 Definitions. The following definitions apply in this subpart: Afterburning. The combustion of any flammable mixture that is... motor. Essential parts include the parts that constitute the flame-arresting path and those necessary...

  7. Fluidized bed incinerator development

    International Nuclear Information System (INIS)

    A fluidized bed incinerator is being developed for burning rad contaminated solid and liquid waste materials. In situ neutralization of acid gases by the bed material, catalytic afterburning, and gas filtration are used to produce a clean flue gas without the use of aqueous scrubbing

  8. Simulation of underexpanded supersonic jet flows with chemical reactions

    Institute of Scientific and Technical Information of China (English)

    Fu Debin; Yu Yong; Niu Qinglin

    2014-01-01

    To achieve a detailed understanding of underexpanded supersonic jet structures influenced by afterburning and other flow conditions, the underexpanded turbulent supersonic jet with and without combustions are investigated by computational fluid dynamics (CFD) method. A program based on a total variation diminishing (TVD) methodology capable of predicting complex shocks is created to solve the axisymmetric expanded Navier-Stokes equations containing transport equations of species. The finite-rate ratio model is employed to handle species sources in chemical reactions. CFD solutions indicate that the structure of underexpanded jet is typically influenced by the pressure ratio and afterburning. The shock reflection distance and maximum value of Mach number in the first shock cell increase with pressure ratio. Chemical reactions for the rocket exhaust mostly exist in the mixing layer of supersonic jet flows. This tends to reduce the intensity of shocks existing in the jet, responding to the variation of thermal parameters.

  9. Validation study of large-eddy simulations of wake stabilized reacting flows using artificial flame thickening approaches

    OpenAIRE

    Kewlani, G.; Vogiatzaki, K.; Shanbhogue, S.; Ghoniem, A. F.

    2013-01-01

    Wake flows are the preferred mode of flame stabilization in lean premixed combustion in gas turbine engines, low NOx burners, afterburners etc. These flows exhibit inherent unsteadiness and for their numerical modeling and simulations, large eddy simulation (LES) techniques with an appropriate combustion model and reaction mechanism afford a balance between computational complexity and predictive accuracy. Before using them in practical systems, these techniques must be validated against expe...

  10. Hollow screw-like drill in plasma using an intense Laguerre–Gaussian laser

    OpenAIRE

    Wang, Wenpeng; Shen, Baifei; ZHANG, XIAOMEI; Zhang, Lingang; Shi, Yin; Xu, Zhizhan

    2015-01-01

    With the development of ultra intense laser technology, MeV ions from the laser foil interaction have been obtained by different mechanisms, such as target normal sheath acceleration, radiation pressure acceleration, collisionless shock acceleration, breakout afterburner, and a combination of different mechanisms. These energetic ion beams can be applied in fast ignition for inertial confinement fusion, medical therapy, and proton imaging. However, these ions are mainly accelerated in the las...

  11. Improvement of the performance of a turbo-ramjet engine for UAV and missile applications

    OpenAIRE

    Krikellas, Dimitrios

    2003-01-01

    Approved for public release, distribution unlimited An existing turbo-ramjet engine was modified in order to increase the produced thrust and sustain combustion at increased freejet Mach numbers. The engine's afterburner fuel system was redesigned to improve the vaporization and atomization of the fuel. The engine performed satisfactorily at speeds up to Mach 0.3, producing 100% more thrust over the baseline turbojet. The data acquisition system of the turbo-ramjet engine's performance mea...

  12. Level 1 environmental assessment of cupola emissions at the Tioga Foundry

    Energy Technology Data Exchange (ETDEWEB)

    Menzies, K.T.; Adams, J.W.; Thrun, K.E.

    1984-01-01

    Sampling and analysis was undertaken to characterize and quantify particulate, organic and inorganic chemical concentrations in gaseous effluents downstream of an afterburner (AFB) or stack air addition (SAA) system in a cupola at the Tioga Casting Company in Owego, New York. The US Environmental Protection Agency/Industrial Environmental Research Laboratory (EPA/IERL) Level 1 environmental assessment procedures were used to determine if the level of pollutants present differed when using the AFB versus the SAA control device for reduction of carbon monoxide (CO) concentrations.

  13. Metallic materials corrosion in the CRNL radwaste incinerator

    International Nuclear Information System (INIS)

    Corrosion coupon evaluation and in-service materials performance for the CRNL waste incinerator has been carried out since 1980. Data are presented to show that types 309, 310 and 446 stainless steel, Alloy 625 and Alloy 333 all perform well in short-term tests in the afterburner environment (850-10000C) but are subject to sigma-phase embrittlement and grain boundary carbide precipitation following long-term exposures. Several alloys performed satisfactorily in the primary chamber (5000C), and the material of construction, type 310 stainless steel, continues to provide good service

  14. Further Improvement and System Integration of High Temperature Polymer Electrolyte Membrane Fuel Cells

    DEFF Research Database (Denmark)

    Li, Qingfeng; Jensen, Jens Oluf

    The strategic developments of the FURIM are in three steps: (1) further improvement of the high temperature polymer membranes and related materials; (2) development of technological units including fuel cell stack, hydrocarbon reformer and afterburner, that are compatible with the HT-PEMFC; and (3...... hydrocarbon reformer and a catalytic burner are to be developed and integrated with the stack. The key issue of the project is development and improvement of the temperature-resistant polymer membranes with respect to durability, conductivity, mechanical and other properties. For this purpose, basic polymers...

  15. Niobium alloy heat pipes for use in oxidizing environments

    International Nuclear Information System (INIS)

    Niobium alloys have been used for many years in rocket propulsion systems and afterburner sections of gas turbine engines. In these applications, adequate oxidation resistance is provided by protective silicide coatings. By utilizing these coatings and niobium powder metallurgy to produce porous wicks, it has been demonstrated that niobium alloy heat pipes can comfortably operate in flame temperatures exceeding 3000 K. Results of lithium corrosion tests on C-103 (Nb-10%Hf-1%Ti) up to 1477 K will be presented along with thermal performance data for specific heat pipe designs

  16. Niobium alloy heat pipes for use in oxidizing environments

    Science.gov (United States)

    Craig Wojcik, C.

    1991-01-01

    Niobium alloys have been used for many years in rocket propulsion systems and afterburner sections of gas turbine engines. In these applications, adequate oxidation resistance is provided by protective silicide coatings. By utilizing these coatings and niobium powder metallurgy to produce porous wicks, it has been demonstrated that niobium alloy heat pipes can comfortably operate in flame temperatures exceeding 3000 K. Results of lithium corrosion tests on C-103 (Nb-10%Hf-1%Ti) up to 1477 K will be presented along with thermal performance data for specific heat pipe designs.

  17. Development of low temperature SOFC systems for remote power applications

    International Nuclear Information System (INIS)

    Global Thermoelectric Inc. is developing low cost, low temperature (600oC to 700oC) solid oxide fuel cell systems for applications including remote, automotive and residential power generation. Remote power applications in oil and gas and telecommunication markets have been targeted. Kilowatt level SOFC systems complement Global's existing product line of thermoelectric generators which generate up to 550 W. A complete thermally integrated self-standing 1 kW laboratory system has been designed and tested at Global using sulfur-containing natural gas. The system is composed of three main sectors: SOFC stack, integrated module (afterburner, heat exchanger, and fuel processor), and low temperature regenerative heat exchangers. In the integrated module, indirect internal steam reforming at ambient pressure and S/C ratios of 2.0 to 3.5 was accomplished using a nickel/alumina carrier catalyst. The waste heat from the afterburner was used to drive the endothermic steam reforming reaction and further preheat incoming air. Methane conversions approached equilibrium for the test conditions examined. Global's stack development of planar anode-supported cell technology has resulted in a modular sub-stack arrangement complete with integral gas manifolding in each sub-stack. This arrangement allows for flexibility in stack configurations and excellent serviceability. The development of a pre-commercial 3 kW partial oxidation system will also be discussed. (author)

  18. The potential for extending the spectral range accessible to the european X-ray free electron laser in the direction of longer wavelengths

    CERN Document Server

    Saldin, E L; Yurkov, M V

    2004-01-01

    The baseline specifications of European XFEL give a range of wavelengths between 0.1 nm and 2 nm. This wavelength range at fixed electron beam energy 17.5 GeV can be covered by operating the SASE FEL with three undulators which have different period and tunable gap. A study of the potential for the extending the spectral range accessible to the XFEL in the direction of longer wavelengths is presented. The extension of the wavelength range to 6 nm would be cover the water window in the VUV region, opening the facility to a new class of experiments. There are at least two possible sources of VUV radiation associated with the X-ray FEL; the "low (2.5 GeV) energy electron beam dedicated" and the " 17.5 GeV spent beam parasitic" (or "after-burner") source modes. The second alternative, "after-burner undulator" is the one we regard as most favorable. It is possible to place an undulator as long as 80 meters after 2 nm undulator. Ultimately, VUV undulator would be able to deliver output power approaching 100 GW. A b...

  19. Simulation and material testing of jet engines

    International Nuclear Information System (INIS)

    The NASA software engine simulator version U 1.7a beta has been used for simulation and material testing of jet engines. Specifications of Modem Jet Engines are stated, and then engine simulator is applied on these specifications. This simulator can simulate turbojet, afterburner, turbofan and ram jet. The material of many components of engine may be varied. Conventional and advanced materials for jet engines can be simulated and tested. These materials can be actively cooled to increase the operating temperature limit. As soon as temperature of any engine component exceeds the temperature limit of material, a warning message flashes across screen. Temperature Limits Exceeded. This flashing message remainst here until necessaryc hangesa re carried out in engine operationp rocedure. Selection Criteria of Engines is stated for piston prop, turboprop, turbofan, turbojet, and turbojet with afterburner and Ramjet. Several standard engines are modeled in Engine Simulator. These engines can. be compared by several engineering specifications. The design, modeling, simulation and testing of engines helps to better understand different types of materials used in jet engines. (author)

  20. Transient Two-Dimensional Analysis of Side Load in Liquid Rocket Engine Nozzles

    Science.gov (United States)

    Wang, Ten-See

    2004-01-01

    Two-dimensional planar and axisymmetric numerical investigations on the nozzle start-up side load physics were performed. The objective of this study is to develop a computational methodology to identify nozzle side load physics using simplified two-dimensional geometries, in order to come up with a computational strategy to eventually predict the three-dimensional side loads. The computational methodology is based on a multidimensional, finite-volume, viscous, chemically reacting, unstructured-grid, and pressure-based computational fluid dynamics formulation, and a transient inlet condition based on an engine system modeling. The side load physics captured in the low aspect-ratio, two-dimensional planar nozzle include the Coanda effect, afterburning wave, and the associated lip free-shock oscillation. Results of parametric studies indicate that equivalence ratio, combustion and ramp rate affect the side load physics. The side load physics inferred in the high aspect-ratio, axisymmetric nozzle study include the afterburning wave; transition from free-shock to restricted-shock separation, reverting back to free-shock separation, and transforming to restricted-shock separation again; and lip restricted-shock oscillation. The Mach disk loci and wall pressure history studies reconfirm that combustion and the associated thermodynamic properties affect the formation and duration of the asymmetric flow.

  1. Burnout control at the Albright coal-waste-bank fire. Rept. of investigations/1991

    International Nuclear Information System (INIS)

    Burnout Control is a process developed by the U.S. Bureau of Mines for accelerating the burning of wasted coal fires in situ, while at the same time controlling the heat and fumes produced. The Albright fire project is a first field trial of Burnout Control as applied to a coal waste bank. An exhaust ventilation system was designed and constructed and then operated over a 1-year period at the site of an existing abandoned mine land fire near the town of Albright, W.V. While predicted exhaust gas temperatures of 900 C and thermal power levels of 5 MW were achieved at 20- to 30-in H2O vacuum levels, problems were encountered with engineering designs, equipment breakdown, and fuel-rich combustion that curtailed the time period of satisfactory operation. Effective afterburning of the exhaust gases (as they were drawn from the bank) corrected the problems associated with combustion stoichiometry and led to high thermal outputs. It is believed that with (1) improvements in engineering design and construction, (2) better control of the afterburning process, and (3) the use of conventional stack gas air-pollution controls, Burnout Control can be applied successfully to a coal waste bank fire

  2. Method of generating electricity using an endothermic coal gasifier and MHD generator

    Science.gov (United States)

    Marchant, David D.; Lytle, John M.

    1982-01-01

    A system and method of generating electrical power wherein a mixture of carbonaceous material and water is heated to initiate and sustain the endothermic reaction of carbon and water thereby providing a gasified stream containing carbon monoxide, hydrogen and nitrogen and waste streams of hydrogen sulfide and ash. The gasified stream and an ionizing seed material and pressurized air from a preheater go to a burner for producing ionized combustion gases having a temperature of about 5000.degree. to about 6000.degree. F. which are accelerated to a velocity of about 1000 meters per second and passed through an MHD generator to generate DC power and thereafter through a diffuser to reduce the velocity. The gases from the diffuser go to an afterburner and from there in heat exchange relationship with the gasifier to provide heat to sustain the endothermic reaction of carbon and water and with the preheater to preheat the air prior to combustion with the gasified stream. Energy from the afterburner can also be used to energize other parts of the system.

  3. Hybrid Laser-Plasma Wakefield Acceleration

    International Nuclear Information System (INIS)

    The concept of driving a driver/witness-type plasma wakefield accelerator (PWFA) with quasimonoenergetic double electron bunches from a laser wakefield accelerator (LWFA) is studied. In the quasimonoenergetic LWFA/SMLWFA (self-modulated LWFA) regime, it is possible to generate multiple quasimonoenergetic electron bunches with durations of only a few fs and distances of only a few tens of fs with a comparably simple experimental setup. In a subsequent high-density plasma afterburner stage the witness bunch energy can be boosted in the plasma wakefield generated by the driver. Such a hybrid system can increase the maximum energy output of a laser wakefield accelerator and is well suited to study driver/witness plasma accelerator phenomena and can be used as a cost-effective test-bed for future high-energy plasma-based accelerators.

  4. Progress report about research and development activities in 1992. Annual report of the Laboratory of Isotope Technology (LIT)

    International Nuclear Information System (INIS)

    The R and D activities focussed on thermal waste treatment methods and on waste incineration in particular; for this process, closed toxic substance balances have been established and process engineering studies have been performed, aimed at achieving a reduction of pollutants in the off-gas. The decisive factors in this process have been reviewed, namely the design of the firing chamber, the air flow control, the temperatures in the combusition chamber and the after-burner, and the residence time in the various temperature zones, because these are the process parameters determining to what degree the organic substances are destroyed, whether heavy metals remaining in the tailings are sufficiently immobilized, and whether the particulate or gaseous pollutants are converted as desired into substances that can be easily filtered or otherwise separated. (BBR)

  5. Circular polarization opportunities at the SASE3 undulator line of the European XFEL

    CERN Document Server

    Serkez, Svitozar; Kocharyan, Vitali; Saldin, Evgeni

    2016-01-01

    XFELs provide X-ray pulses with unprecedented peak brightness and ultrashort duration. They are usually driven by planar undulators, meaning that the output radiation is linearly polarized. For many experimental applications, however, polarization control is critical: besides the ability to produce linearly polarized radiation, one often needs the possibility of generating circularly polarized radiation with a high, stable degree of polarization. This may be achieved by using a first part of the XFEL undulator to produce bunching and then, by propagating the the bunched beam through an "afterburner" - a short undulator with tunable polarization, where only limited gain takes place. One of the issues that one needs to consider in this case is the separation of the circularly polarized radiation obtained in the radiator from the linearly polarized background produced in the first part of the FEL. In this article we review several methods to do so, including the inverse tapering technique. In particular, we use ...

  6. Turbofan gas turbine engine with variable fan outlet guide vanes

    Science.gov (United States)

    Wood, Peter John (Inventor); Zenon, Ruby Lasandra (Inventor); LaChapelle, Donald George (Inventor); Mielke, Mark Joseph (Inventor); Grant, Carl (Inventor)

    2010-01-01

    A turbofan gas turbine engine includes a forward fan section with a row of fan rotor blades, a core engine, and a fan bypass duct downstream of the forward fan section and radially outwardly of the core engine. The forward fan section has only a single stage of variable fan guide vanes which are variable fan outlet guide vanes downstream of the forward fan rotor blades. An exemplary embodiment of the engine includes an afterburner downstream of the fan bypass duct between the core engine and an exhaust nozzle. The variable fan outlet guide vanes are operable to pivot from a nominal OGV position at take-off to an open OGV position at a high flight Mach Number which may be in a range of between about 2.5-4+. Struts extend radially across a radially inwardly curved portion of a flowpath of the engine between the forward fan section and the core engine.

  7. An Electron Bunch Compression Scheme for a Superconducting Radio Frequency Linear Accelerator Driven Light Source

    International Nuclear Information System (INIS)

    We describe an electron bunch compression scheme suitable for use in a light source driven by a superconducting radio frequency (SRF) linac. The key feature is the use of a recirculating linac to perform the initial bunch compression. Phasing of the second pass beam through the linac is chosen to de-chirp the electron bunch prior to acceleration to the final energy in an SRF linac ('afterburner'). The final bunch compression is then done at maximum energy. This scheme has the potential to circumvent some of the most technically challenging aspects of current longitudinal matches; namely transporting a fully compressed, high peak current electron bunch through an extended SRF environment, the need for a RF harmonic linearizer and the need for a laser heater. Additional benefits include a substantial savings in capital and operational costs by efficiently using the available SRF gradient.

  8. Chemical aspects of incinerating highly chlorinated and actinide α contaminated organic waste: application to the Iris process

    International Nuclear Information System (INIS)

    A fraction of the waste produced by nuclear activities is combustible, and thus suitable for incineration to produce gases, ash and fines. A typical composition representative of actual organic waste mixtures was defined for the purpose of investigating possible heat treatment processes; the composition is identified according to components Table 1 and elements Table II. The high polyvinyl chloride (PVC) content is responsible for the high chlorine potential in the process equipment. The quantity and quality of the resulting solid residue depends entirely on the inorganic load of the organic waste, whose behavior is entirely conditioned by the process conditions. For example, pure polyethylene is totally converted to gases (water and carbon dioxide), while the composition shown in Table II produces a range of oxides and chlorides. The high chlorine content results in partial chlorination of the inorganic compounds, but can also lead to interactions with the process equipment. The temperature dependent variation of the chlorination equilibrium constants of various metals clearly shows that all the elements of technological alloys may be subject to active corrosion by hydrochloric acid. However, the corresponding oxides-notably alumina-are much less sensitive to corrosion; aluminum-based alloys are therefore preferred for incinerator construction and to limit corrosion by hydrochloric acid. Thermodynamic and kinetic studies led to the development of the IRIS three-step process. Gas emissions occurring during processing of solid materials are completely oxidized in the after-burning step at 1100 deg C, and are then ducted to a HERA filtration system capable of retaining all the actinide α radionuclides. Although corrosion-related problems are attenuated in the two-step process chlorine can combine with the inorganic waste material to form chlorides with potentially damaging effects on the system; this is the case for zinc chloride and for volatile chlorides in

  9. Further Improvement and System Integration of High Temperature Polymer Electrolyte Membrane Fuel Cells

    DEFF Research Database (Denmark)

    Li, Qingfeng; Jensen, Jens Oluf

    The new development in the field of polymer electrolyte membrane fuel cell (PEMFC) is high temperature PEMFC for operation above 100°C, which has been successfully demonstrated through the previous EC Joule III and the 5th framework programme. New challenges are encountered, bottlenecks for the new...... of the FURIM are in three steps: (1) further improvement of the high temperature polymer membranes and related materials; (2) development of technological units including fuel cell stack, hydrocarbon reformer and afterburner, that are compatible with the HT-PEMFC; and (3) integration of the HT...... catalytic burner are to be developed and integrated with the stack. The key issue of the project is development and improvement of the temperature-resistant polymer membranes with respect to durability, conductivity, mechanical and other properties. For this purpose, basic polymers will be first synthesized...

  10. Further Improvement and System Integration of High Temperature Polymer Electrolyte Membrane Fuel Cells

    DEFF Research Database (Denmark)

    Jensen, Jens Oluf; Li, Qingfeng

    Polymer electrolyte membrane fuel cell (PEMFC) technology based on Nafion membranes can operate at temperatures around 80°C. The new development in the field is high temperature PEMFC for operation above 100°C, which has been successfully demonstrated through the previous EC Joule III and the 5th...... system integration of the high temperature PEMFC. The strategic developments of the FURIM are in three steps: (1) further improvement of the high temperature polymer membranes and related materials; (2) development of technological units including fuel cell stack, hydrocarbon reformer, afterburner and......, conductivity, mechanical and other properties. For this purpose, basic polymers will be first synthesized and optimized. Different routes to functionalize the polymers will be explored to increate proton conductivity. By the development of advanced materials, demonstration of the high temperature PEMFC stack...

  11. Sludge incineration: good practice and environmental aspects

    Energy Technology Data Exchange (ETDEWEB)

    Braguglia, C.M.; Mininni, G.; Marani, D.; Lotito, V.

    2003-07-01

    Growing difficulties in the sludge utilization in agriculture or landfill make incineration an attractive alternative for sludge disposal. Capital and operating costs and concern about gaseous emissions may however limit convenience and acceptance. In this paper a model is presented for optimisation of the cake concentration before the furnace, allowing an autogenous operation with a minimization of exhaust gas production. As far as emissions of heavy metals and organic micropollutants at the stack is concerned, results of tests on a demonstrative plant, including a fluidised bed and a rotary kiln furnace, are presented. The tests were carried out in different feeding (sludge alone or spiked with chlorinated hydrocarbons) and operating conditions (temperature of the afterburning chamber). (author)

  12. Hollow screw like drill in plasma using an intense Laguerre Gaussian laser

    CERN Document Server

    Wang, Wenpeng; Zhang, Xiaomei; Zhang, Lingang; Shi, Yin; Xu, Zhizhan

    2014-01-01

    With the development of ultra intense laser technology, MeV ions from the laser foil interaction have been obtained by different mechanisms, such as target normal sheath acceleration, radiation pressure acceleration, collisionless shock acceleration, breakout afterburner, and a combination of different mechanisms. These energetic ion beams can be applied in fast ignition for inertial confinement fusion, medical therapy, and proton imaging. However, these ions are mainly accelerated in the laser propagation direction, and the ion acceleration in an azimuthal orientation is scarcely mentioned. Here, a doughnut Laguerre Gaussian LG laser is used for the first time to study the laser plasma interaction in the relativistic intensity regime in three dimensional particle in cell simulations. Studies have shown that a novel rotation of the plasma is produced from the hollow screw like drill of a LG mode laser. The angular momentum of the protons in the longitudinal direction produced by the LG laser is remarkably enh...

  13. Raising i.c. engine catalytic converter temperature

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, T.J.

    1994-10-19

    The engine when cold has delayed completion of combustion and advance of the exhaust event. Combustion of the exhaust gases is completed within the exhaust system in order to raise the temperature of the catalytic convertor. An ECV receives engine speed, load and temperature inputs and controls ignition timing, and/or the injection timing of part or all the fuel, and/or exhaust recirculation, and/or the number of inlet valves per cylinder and/or the number of spark plugs per cylinder which are operative and the timing of exhaust valve closure or the complete exhaust event in a four-stroke engine or the exhaust port geometry in a two-stroke engine. An afterburner may be provided upstream of the convertor. (UK)

  14. Towards Zeptosecond-Scale Pulses from X-Ray Free-Electron Lasers

    CERN Document Server

    Dunning, D J; Thompson, N R

    2013-01-01

    The short wavelength and high peak power of the present generation of free-electron lasers (FELs) opens the possibility of ultra-short pulses even surpassing the present (tens to hundreds of attoseconds) capabilities of other light sources - but only if x-ray FELs can be made to generate pulses consisting of just a few optical cycles. For hard x-ray operation (~0.1nm), this corresponds to durations of approximately a single attosecond, and below into the zeptosecond scale. This talk will describe a novel method to generate trains of few-cycle pulses, at GW peak powers, from existing x-ray FEL facilities by using a relatively short 'afterburner'. Such pulses would enhance research opportunity in atomic dynamics and push capability towards the investigation of electronic-nuclear and nuclear dynamics. The corresponding multi-colour spectral output, with a bandwidth envelope increased by up to two orders of magnitudes over SASE, also has potential applications.

  15. Design and development of major balance of plant components in solid oxide fuel cell system

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Wen-Tang; Huang, Cheng-Nan; Tan, Hsueh-I; Chao, Yu [Institute of Nuclear Energy Research Atomic Energy Council, Taoyuan County 32546 (Taiwan, Province of China); Yen, Tzu-Hsiang [Green Technology Research Institute, CPC Corporation, Chia-Yi City 60036 (Taiwan, Province of China)

    2013-07-01

    The balance of plant (BOP) of a Solid Oxide Fuel Cell (SOFC) system with a 2 kW stack and an electric efficiency of 40% is optimized using commercial GCTool software. The simulation results provide a detailed understanding of the optimal operating temperature, pressure and mass flow rate in all of the major BOP components, i.e., the gas distributor, the afterburner, the reformer and the heat exchanger. A series of experimental trials are performed to validate the simulation results. Overall, the results presented in this study not only indicate an appropriate set of operating conditions for the SOFC power system, but also suggest potential design improvements for several of the BOP components.

  16. Investigation of a process for the pyrolysis of plutonium contaminated combustible solid waste

    International Nuclear Information System (INIS)

    Pyrolysis offers an attractive first-stage alternative to incineration as a means of weight and volume reduction of solide combustible waste P.C.M, if it is required to recover plutonium from the final product. The avoidance of turbulent conditions associated with incineration should lead to less carry-over of particulates, and the lower operating temperature approximately 7000C should be most advantageous to the choice of constructional materials and to plant life. The char product from pyrolysis may be oxidised to a final ash at similarly acceptable low temperatures by passing air over a stirred bed of materials. The recently received draft designs for a cyclone after-burner (plus associated scrubbers and filters etc) offer an attractive method of dispensing of the volatile products of pyrolysis

  17. Analysis of the turbojet engine for propulsion of supersonic fighter airplanes / David S. Gabriel, Richard P. Krebs, E.Clinton Wilcox, Stanley L.Koutz

    Science.gov (United States)

    Gabriel, David S; Krebs, Richard P; Wilcox, E Clinton; Koutz, Stanley L

    1953-01-01

    An analytical investigation was made of two supersonic interceptor type airplanes to determine the most desirable turbojet engine characteristics for this application The airplanes were designed differently primarily because of the amount of subsonic flight incorporated in the flight plan--one flight having none and the other, a cruise radius of 400 nautical miles. Several power plant design variables were varied independently to determine the effect of changes in each parameter on airplane performance. These parameters included compressor pressure ratio, compressor efficiency, turbine-inlet temperature, afterburner temperature, engine specific weight, and air-handling capacity. The effects of using a convergent-divergent exhaust nozzle and of changing the design flight Mach number were also investigated.

  18. Influence of clustering and hadron potentials on the rapidity distribution of protons from the UrQMD model

    CERN Document Server

    Li, Qingfeng; Wang, Xiaobao; Shen, Caiwan; Bleicher, Marcus

    2015-01-01

    The Ultra-relativistic Quantum Molecular Dynamics (UrQMD) model supplemented by potentials for both pre-formed hadrons and confined baryons (called UrQMD/M) are used to describe rapidity distributions of both the E895 proton data at AGS energies and the NA49 net proton data at SPS energies. With the help of a coalescence afterburner using only one parameter set of ($R_0$, $P_0$)=(3.8 fm, 0.3 GeV$/$c), both sets of experimental data can be described fairly well except for a small discrepancy seen for the net protons at mid-rapidity from heavy ion collisions (HICs) at high SPS energies. Furthermore, in contrast to the logarithmic dependence with beam energy at SIS energies there are still about 10$\\%$ of protons in clusters from central HICs at the beam energy of $80$ GeV$/$nucleon.

  19. Preliminary Performance Data on Westinghouse Electronic Power Regulator Operating on J34-WE-32 Turbojet Engine in Altitude Wind Tunnel

    Science.gov (United States)

    Ketchum, James R.; Blivas, Darnold; Pack, George J.

    1950-01-01

    The behavior of the Westinghouse electronic power regulator operating on a J34-WE-32 turbojet engine was investigated in the NACA Lewis altitude wind tunnel at the request of the Bureau of Aeronautics, Department of the Navy. The object of the program was to determine the, steady-state stability and transient characteristics of the engine under control at various altitudes and ram pressure ratios, without afterburning. Recordings of the response of the following parameters to step changes in power lever position throughout the available operating range of the engine were obtained; ram pressure ratio, compressor-discharge pressure, exhaust-nozzle area, engine speed, turbine-outlet temperature, fuel-valve position, jet thrust, air flow, turbine-discharge pressure, fuel flow, throttle position, and boost-pump pressure. Representative preliminary data showing the actual time response of these variables are presented. These data are presented in the form of reproductions of oscillographic traces.

  20. Charge density A probe for the nuclear interaction in microscopic transport models

    CERN Document Server

    Galíchet, E; Lecolley, J F; Bougault, R; Butà, A; Colin, J; Cussol, D; Durand, D; Guinet, D; Lautesse, P; Rivet, M F; Borderie, B; Auger, G; Bouriquet, B; Chbihi, A; Frankland, J D; Guiot, B; Hudan, S; Charvet, J L; Dayras, R; Lavaud, F; Neindre, N L; López, O; Manduci, L; Marie, J; Nalpas, L; Normand, J; Pârlog, M; Pawlowski, P; Plagnol, E; Rosato, E; Steckmeyer, J C; Tamain, B; Lauwe, A V; Vient, E; Volant, C; Wieleczko, J P

    2003-01-01

    The transport properties of the sup 3 sup 6 Ar+ sup 5 sup 8 Ni system at 95 A .MeV measured with the INDRA array, are studied within the BNV kinetic equation. A general protocol of comparison between the N-body experimental fragment information and the one-body distribution function is developed using global variables, with a special focus on charge density. This procedure avoids any definition of sources and any use of an afterburner in the simulation. We shall discuss the feasibility of such an approach and the distortions induced by the finite detection efficiency and the completeness requirements of the data selection. The sensitivity of the different global observables to the macroscopic parameters of the effective nuclear interaction will be studied in detail.

  1. Auxiliary power unit based on a solid oxide fuel cell and fuelled with diesel

    Science.gov (United States)

    Lawrence, Jeremy; Boltze, Matthias

    An auxiliary power unit (APU) is presented that is fuelled with diesel, thermally self-sustaining, and based on a solid oxide fuel cell (SOFC). The APU is rated at 1 kW electrical, and can generate electrical power after a 3 h warm-up phase. System features include a "dry" catalytic partial oxidation (CPOX) diesel reformer, a 30 cell SOFC stack with an open cathode, and a porous-media afterburner. The APU does not require a supply of external water. The SOFC stack is an outcome of a development partnership with H.C. Starck GmbH and Fraunhofer IKTS, and is discussed in detail in an accompanying paper.

  2. Characterization of short-pulse laser driven neutron source

    Science.gov (United States)

    Falk, Katerina; Jung, Daniel; Guler, Nevzat; Deppert, Oliver; Devlin, Matthew; Fernandez, J. C.; Gautier, D. C.; Geissel, M.; Haight, R. C.; Hegelich, B. M.; Henzlova, Daniela; Ianakiev, K. D.; Iliev, Metodi; Johnson, R. P.; Merrill, F. E.; Schaumann, G.; Schoenberg, K.; Shimada, T.; Taddeucci, T. N.; Tybo, J. L.; Wagner, F.; Wender, S. A.; Wurden, G. A.; Favalli, Andrea; Roth, Markus

    2014-10-01

    We present a full spectral characterization of a novel laser driven neutron source, which employed the Break Out Afterburner ion acceleration mechanism. Neutrons were produced by nuclear reactions of the ions deposited on Be or Cu converters. We observed neutrons at energies up to 150 MeV. The neutron spectra were measured by five neutron time-of-flight detectors at various positions and distances from the source. The nTOF detectors observed that emission of neutrons is a superposition of an isotropic component peaking at 3.5--5 MeV resulting from nuclear reactions in the converter and a directional component at 25--70 MeV, which was a product of break-up reaction of the forward moving deuterons. Energy shifts due to geometrical effects in BOA were also observed.

  3. Cleaning of outgoing air at companies reprocessing residual material; Abluftreinigung fuer Reststoffverwertungsbetriebe

    Energy Technology Data Exchange (ETDEWEB)

    Rafflenbeul, R. [Rafflenbeul und Partner, Frankfurt am Main (Germany)

    1996-05-01

    With the extension of the federal act for the protection against nuisances to companies reprocessing residual material and, concomitantly, their obligation from 1997 to obtain a licence, outgoing-air cleaning systems for the removal of odorous nuisances will become indispensable. Because of want of information on the part of many operators, scrubbers, and in part even air cleaning systems with after-burning, are still frequently used. The article gives an overview of the different techniques for cleaning outgoing air such as scrubbers, biological methods as well as plasma and bioplasma techniques. (orig./SR) [Deutsch] Mit der Neueingliederung der Reststoffverwertungsbetriebe in das Bundesimmissionschutz-Gesetz, und hiermit verknuepft der ab 1997 erforderlichen Genehmigungspflicht, werden Abluftreinigungsverfahren zur Geruchsbeseitigung unumgehbar. Aus Unkenntnis der Betreiber gelangen immer noch Waschverfahren, zum Teil sogar nachverbrennend wirkende Abluftreinigungssysteme, zur Anwendung. Es wird ein Ueberblick ueber die verschiedenen Abluftreinigungsverfahren wie Waescher, biologische Verfahren sowie Plasma- und Bioplasmaverfahren gegeben. (orig./SR)

  4. An Electron Bunch Compression Scheme for a Superconducting Radio Frequency Linear Accelerator Driven Light Source

    Energy Technology Data Exchange (ETDEWEB)

    C. Tennant, S.V. Benson, D. Douglas, P. Evtushenko, R.A. Legg

    2011-09-01

    We describe an electron bunch compression scheme suitable for use in a light source driven by a superconducting radio frequency (SRF) linac. The key feature is the use of a recirculating linac to perform the initial bunch compression. Phasing of the second pass beam through the linac is chosen to de-chirp the electron bunch prior to acceleration to the final energy in an SRF linac ('afterburner'). The final bunch compression is then done at maximum energy. This scheme has the potential to circumvent some of the most technically challenging aspects of current longitudinal matches; namely transporting a fully compressed, high peak current electron bunch through an extended SRF environment, the need for a RF harmonic linearizer and the need for a laser heater. Additional benefits include a substantial savings in capital and operational costs by efficiently using the available SRF gradient.

  5. Generation and transport of laser accelerated ion beams

    International Nuclear Information System (INIS)

    Currently the LIGHT- Project (Laser Ion Generation, Handling and Transport) is performed at the GSI Helmholtzzentrum fuer Schwerionenforschung GmbH Darmstadt. Within this project, intense proton beams are generated by laser acceleration, using the TNSA mechanism. After the laser acceleration the protons are transported through the beam pipe by a pulsed power solenoid. To study the transport a VORPAL 3D simulation is compared with CST simulation. A criterion as a function of beam parameters was worked out, to rate the importance of space charge. Furthermore, an exemplary comparison of the solenoid with a magnetic quadrupole-triplet was carried out. In the further course of the LIGHT-Project, it is planned to generate ion beams with higher kinetic energies, using ultra-thin targets. The acceleration processes that can appear are: RPA (Radiation Pressure Acceleration) and BOA (Break-Out Afterburner). Therefore the transport of an ion distribution will be studied, as it emerges from a RPA acceleration.

  6. Nonorthogonality analysis of a thermoacoustic system with a premixed V-shaped flame

    International Nuclear Information System (INIS)

    Highlights: • Nonorthogonality analysis of a choked thermoacoustic system is conducted. • A thermoacoustic model of a premixed V-shaped flame is developed. • Nonorthogonality is identified to arise from the boundary condition and the flame. • The contribution from the flame is shown to play a dominant role. • Eigenmodes nonorthogonality leads to transient growth of acoustic disturbances. - Abstract: Thermoacoustic instability occurs in many combustion systems, such as aero-engine afterburners, rocket motors, ramjets and gas turbines. It most often arises due to the coupling between unsteady heat release and acoustic waves. In this work, nonorthogonality analysis of a choked combustor with a gutter confined is conducted. Such configuration is used as a simplified model of the afterburner of an aero-engine. A thermoacoustic model is developed first to study the nonnormal interaction between acoustic disturbances and a premixed V-shaped flame anchored to the tip of the gutter. Eigenmode nonorthogonality analysis is then conducted. The thermoacoustic system is shown to be nonnormal and characterized by nonorthogonal eigenmodes. The nonorthogonality is identified to arise from both the complex boundary condition and the monopole-like flame. However, the contribution from the Robin-type boundary is approximately 1.5% of that from the flame. Thus the flame is identified to play a dominant role. One practical conclusions is that acoustic disturbances undergo transient growth in a combustion system with nonorthogonal eigenmodes. Such finite-time growth, which cannot be predicted by using classical linear theory might trigger high-amplitude self-sustained oscillations

  7. Dioxins, furans and polycyclic aromatic hydrocarbons emissions from a hospital and cemetery waste incinerator

    Science.gov (United States)

    Mininni, Giuseppe; Sbrilli, Andrea; Maria Braguglia, Camilla; Guerriero, Ettore; Marani, Dario; Rotatori, Mauro

    An experimental campaign was carried out on a hospital and cemetery waste incineration plant in order to assess the emissions of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polycyclic aromatic hydrocarbons (PAHs). Raw gases were sampled in the afterburning chamber, using a specifically designed device, after the heat recovery section and at the stack. Samples of slags from the combustion chamber and fly ashes from the bag filter were also collected and analyzed. PCDD/Fs and PAHs concentrations in exhaust gas after the heat exchanger (200-350 °C) decreased in comparison with the values detected in the afterburning chamber. Pollutant mass balance regarding the heat exchanger did not confirm literature findings about the de novo synthesis of PCDD/Fs in the heat exchange process. In spite of a consistent reduction of PCDD/Fs in the flue gas treatment system (from 77% up to 98%), the limit of 0.1 ng ITEQ Nm -3 at the stack was not accomplished. PCDD/Fs emission factors for air spanned from 2.3 up to 44 μg ITEQ t -1 of burned waste, whereas those through solid residues (mainly fly ashes) were in the range 41-3700 μg ITEQ t -1. Tests run with cemetery wastes generally showed lower PCDD/F emission factors than those with hospital wastes. PAH total emission factors (91-414 μg kg -1 of burned waste) were in the range of values reported for incineration of municipal and industrial wastes. In spite of the observed release from the scrubber, carcinogenic PAHs concentrations at the stack (0.018-0.5 μg Nm -3) were below the Italian limit of 10 μg Nm -3.

  8. Simulation and exergetic evaluation of CO2 capture in a solid-oxide fuel-cell combined-cycle power plant

    International Nuclear Information System (INIS)

    Highlights: • An exergetic analysis is used to identify the thermodynamic irreversibilities of a power plant. • The plant includes a solid-oxide fuel-cell unit and CO2 capture. • Additional power generated in the fuel-cell unit enhances the power output of the plant. • The power plant results in a high efficiency compared both to conventional and other CO2 capture plants. • High irreversibilities are found for the solid-oxide fuel cell. - Abstract: The incorporation of fuel cells into power plants can enhance the operational efficiency and facilitate the separation and capture of emissions. In this paper a fuel-cell unit, consisting of solid-oxide fuel-cell stacks, a pre-reformer, and an afterburner is incorporated into a combined-cycle power plant with CO2 capture. The thermodynamic performance of the plant is examined using an exergetic analysis and it is compared with a conventional combined-cycle power plant (reference plant) without CO2 capture, as well as with other plants with CO2 capture. The inefficiencies of the chemical reactions taking place in the fuel-cell unit are found to be the main source of exergy destruction among the plant components. However, the additional power generated in the fuel-cell stacks and the afterburner enhances the overall efficiency and compensates for the energy needed for the capture and compression of the carbon dioxide. When compared with the reference plant and with alternative capture technologies, the solid-oxide fuel-cell plant with CO2 capture operates more efficiently and appears to be a thermodynamically promising approach for carbon capture

  9. Theoretical and experimental studies on emissions from wood combustion

    Energy Technology Data Exchange (ETDEWEB)

    Skreiberg, Oeyvind

    1997-12-31

    This thesis discusses experiments on emissions from wood log combustion and single wood particle combustion, both caused by incomplete combustion and emissions of nitric and nitrous oxide, together with empirical and kinetic NO{sub x} modelling. Experiments were performed in three different wood stoves: a traditional stove, a staged air stove and a stove equipped with a catalytic afterburner. Ideally, biomass fuel does not give a net contribution to the greenhouse effect. However, incomplete combustion was found to result in significant greenhouse gas emissions. Empirical modelling showed the excess air ratio and the combustion chamber temperature to be the most important input variables controlling the total fuel-N to NO{sub x} conversion factor. As the result of an international round robin test of a wood stove equipped with a catalytic afterburner, particle emission measurements were found to be the best method to evaluate the environmental acceptability of the tested stove, since the particle emission level was least dependent of the national standards, test procedures and calculation procedures used. In batch single wood particle combustion experiments on an electrically heated small-scale fixed bed reactor the fuel-N to NO conversion factor varied between 0.11-0.86 depending on wood species and operating conditions. A parameter study and homogeneous kinetic modelling on a plug flow reactor showed that, depending on the combustion compliance in question, there is an optimum combination of primary excess air ratio, temperature and residence time that gives a maximum conversion of fuel-N to N{sub 2}. 70 refs., 100 figs., 26 tabs.

  10. Preliminary results of lab-scale investigations of products of incomplete combustion during incineration of primary and mixed digested sludge.

    Science.gov (United States)

    Braguglia, C M; Bagnuolo, G; Gianico, A; Mininni, G; Pastore, C; Mascolo, G

    2016-03-01

    Separation between primary and secondary sludge treatment could be a valuable solution for sludge management. According to this approach, secondary sludge can be conveniently used in agriculture while primary sludge could be easily dried and incinerated. It follows that some concern may arise from incinerating primary sludge with respect to the current practice to incinerate mixed digested sludge. Incineration of primary and mixed digested municipal sludge was investigated with a lab-scale equipment in terms of emissions of products of incomplete combustion (PICs) during incineration failure modes. PICs can be grouped in three sub-categories, namely aliphatic hydrocarbons (alkanes and alkenes), compounds with a single aromatic ring, and polycyclic aromatic hydrocarbons (PAHs). After-burning temperature was the most important parameter to be controlled in order to minimize emissions of alkanes and alkenes. As for mono-aromatic compounds, benzene and toluene are the most thermally resistant compounds, and in some cases, an after-burning temperature of 1100 °C was not enough to get the complete destruction of benzene leading to a residual emission of 18 mg/kgsludge. PAHs showed an opposite trend with respect to aliphatic and mono-aromatic hydrocarbons being the thermal failure mode the main responsible of PIC emissions. A proper oxygen concentration is more important than elevated temperature thus reflecting the high thermal stability of PAHs. Overall, obtained results, even though obtained under flameless conditions that are different from those of the industrial plants, demonstrated that separation of primary and secondary sludge does not pose any drawbacks or concern regarding primary sludge being disposed of by incineration even though it is more contaminated than mixed digested sludge in terms of organic pollutants. PMID:26520096

  11. Computational Analyses in Support of Sub-scale Diffuser Testing for the A-3 Facility. Part 2; Unsteady Analyses and Risk Assessment

    Science.gov (United States)

    Ahuja, Vineet; Hosangadi, Ashvin; Allgood, Daniel

    2008-01-01

    Simulation technology can play an important role in rocket engine test facility design and development by assessing risks, providing analysis of dynamic pressure and thermal loads, identifying failure modes and predicting anomalous behavior of critical systems. This is especially true for facilities such as the proposed A-3 facility at NASA SSC because of a challenging operating envelope linked to variable throttle conditions at relatively low chamber pressures. Design Support of the feasibility of operating conditions and procedures is critical in such cases due to the possibility of startup/shutdown transients, moving shock structures, unsteady shock-boundary layer interactions and engine and diffuser unstart modes that can result in catastrophic failure. Analyses of such systems is difficult due to resolution requirements needed to accurately capture moving shock structures, shock-boundary layer interactions, two-phase flow regimes and engine unstart modes. In a companion paper, we will demonstrate with the use of CFD, steady analyses advanced capability to evaluate supersonic diffuser and steam ejector performance in the sub-scale A-3 facility. In this paper we will address transient issues with the operation of the facility especially at startup and shutdown, and assess risks related to afterburning due to the interaction of a fuel rich plume with oxygen that is a by-product of the steam ejectors. The primary areas that will be addressed in this paper are: (1) analyses of unstart modes due to flow transients especially during startup/ignition, (2) engine safety during the shutdown process (3) interaction of steam ejectors with the primary plume i.e. flow transients as well as probability of afterburning. In this abstract we discuss unsteady analyses of the engine shutdown process. However, the final paper will include analyses of a staged startup, drawdown of the engine test cell pressure, and risk assessment of potential afterburning in the facility. Unsteady

  12. Thermopiles - a new thermal desorption technology for recycling highly organic contaminated soils down to natural levels

    International Nuclear Information System (INIS)

    The ThermopileR technology, developed by Deep Green, provides an implementation system allowing to treat hydrocarbon and PAH contaminated materials down to natural levels or down to levels where they are treatable with a traditional thermal desorption unit, in a controlled batch system. The materials are indirectly heated while a substantial part of the energy is reused to heat the pile of soil. The system differs from most of the indirect thermal desorption systems by its very high energetic efficiency as well as its ability to be set -up remotely. The system does not face preferential path problems, since the heating medium is only conduction, which is very indifferent with regard to soil type (clay, sand, silt, etc.). That property is critical to an in-depth clean-up with a batch system. Other systems, based on heat, are mostly sending heat vectors (gases, hot air, steam, etc.) through the soil, which implies preferential paths, which are the main cause for not completely cleaning the soil with most batch technologies (down to natural levels). The soil to treat is placed in a pile or in a modular container in which perforated steel pipes are installed along a hexagonal pattern. During treatment those pipes are heated by hot gases (about 600 deg. C) coming from the afterburner. Consequently the soil reaches the contaminant's desorption temperature. The desorbed pollutants are then drawn by convection and diffusion into the heating pipes via the perforations. Once in the pipes the desorbed gases are mixed with the heating gases. They are sucked by the ID fan and sent to the afterburner. The hydrocarbons in gaseous phase are then oxidized in the afterburner. In this manner, they provide a part of the energy needed to heat the soil itself. The pilot unit is also equipped with a purge that allows the evacuation of a part of the gases circulating in the system; Different additional gas treatments can be applied as required by the type of contaminants and the emissions

  13. 进气道结构对含硼固冲发动机二次燃烧性能影响分析%Analyzing the Performance of Boron﹣Based Propellant Ducted Engine with Different Air Inlet Structure

    Institute of Scientific and Technical Information of China (English)

    胡旭; 徐义华; 王洪远; 曾卓雄

    2014-01-01

    The numerical simulation of three﹣dimensional two﹣Phase flow in the boron﹣based ProPellant ducted rocket motor with the different inlet structure are carried out by the standard k -εturbulence mod﹣el ,one﹣steP eddy﹣dissiPation combustion model and the ignition and combustion of boron Particles of KING in high﹣sPeed flow. The ignition and combustion of boron Particles and the combustion efficiency of com﹣bustion gas in afterburning chamber of motor with six tyPes of air﹣inlet structures are analyzed. Combustion efficiency of gas is the highest under the inlet structure of bilateral 180 ° and it is the lowest at the case of inlet structure of 90° on both down side. The combustion efficiency of boron Particles is the highest at the case of inlet structure of bilateral 180° and it is the lowest under the center air intake structure. The total combustion efficiency in afterburning chamber is the highest when the inlet structure for bilateral 180 ° is a﹣doPted and it is the lowest under the structure of center air intake.%采用标准k-ε湍流模型,单步涡团耗散燃烧模型以及高速气流作用下KING硼粒子点火燃烧模型,开展了不同进气道结构下冲压发动机补燃室内含硼颗粒三维两相燃烧流动数值模拟;分析了在6种进气道结构对硼颗粒点火燃烧以及燃气燃烧效率的影响;研究结果表明:在相同的边界条件下,进气道结构形式对硼颗粒点火影响不大;燃气燃烧效率在双侧180°的进气结构下最高,双下侧90°进气结构的燃气燃烧效率最低;硼颗粒燃烧效率在双侧180°时燃烧效率最高,在中心进气结构下硼燃烧效率最低;补燃室内总燃烧效率在双侧180°进气道结构时最高,在中心进气结构下最低。

  14. Effect of LiF Coating on the Thermal Oxidation Characteristics for Boron Powder%LiF包覆对硼粉热氧化特性的影响

    Institute of Scientific and Technical Information of China (English)

    陈涛; 张先瑞; 王园园; 黄凌; 肖金武

    2013-01-01

    In order to investigate the effect of LiF coating on the thermal oxidation characteristics for amorphous boron powder,the thermal analysis experiment of boron coated with LiF (BLiF) was conducted by DSC-TC. Propellant samples containing BLif were prepared. The heat of detonation and heat of combustion were determined by an oxygen bomb calorimeter. The effects of BLif on the energy release features in primary combustion and after-burning processes of the propellant were discussed. The results indicate that in comparison with amorphous boron, BLiF shows a fast oxidation reaction at 599 XL ,and a 39. 9% higher percentage of boron participated in B/O reaction. The propellant containing BLiF makes primary combustion and after-burning energy release efficiencies (ηc1 and ηc2) increased and combustion efficiencies of B enhanced significantly from 65.48% to 81 .57%. This is due to the consumption of B2O3 layer on the boron particle surface via endothermic reaction of LiF and B2O3 at high temperature and the acceleration of B/O reaction.%为考察LiF包覆对硼粉热氧化特性的影响,采用DSC-TG技术对LiF包覆硼(BLiF)进行热分析试验.制备了含BLiF的推进剂样品.采用氧弹量热计测试其爆热和热值.考察了BLiF对推进剂一次、二次燃烧过程中能量释放特性的影响.结果表明:与无定形硼相比,BLiF在599℃存在快速氧化反应,有39.9%(质量百分数)的B参与了B/O反应.含BLiF的推进剂使一次能量释放效率和二次能量释放效率明显提高,硼的燃烧效率从65.48%提高到81.57%.这是由高温下LiF通过吸热反应消耗硼粉表面B2O3氧化层,加速B/O反应所引起的.

  15. Beyond injection: Trojan horse underdense photocathode plasma wakefield acceleration

    International Nuclear Information System (INIS)

    An overview on the underlying principles of the hybrid plasma wakefield acceleration scheme dubbed 'Trojan Horse' acceleration is given. The concept is based on laser-controlled release of electrons directly into a particle-beam-driven plasma blowout, paving the way for controlled, shapeable electron bunches with ultralow emittance and ultrahigh brightness. Combining the virtues of a low-ionization-threshold underdense photocathode with the GV/m-scale electric fields of a practically dephasing-free beam-driven plasma blowout, this constitutes a 4th generation electron acceleration scheme. It is applicable as a beam brightness transformer for electron bunches from LWFA and PWFA systems alike. At FACET, the proof-of-concept experiment 'E-210: Trojan Horse Plasma Wakefield Acceleration' has recently been approved and is in preparation. At the same time, various LWFA facilities are currently considered to host experiments aiming at stabilizing and boosting the electron bunch output quality via a trojan horse afterburner stage. Since normalized emittance and brightness can be improved by many orders of magnitude, the scheme is an ideal candidate for light sources such as free-electron-lasers and those based on Thomson scattering and betatron radiation alike.

  16. High-Flux Femtosecond X-Ray Emission from Controlled Generation of Annular Electron Beams in a Laser Wakefield Accelerator.

    Science.gov (United States)

    Zhao, T Z; Behm, K; Dong, C F; Davoine, X; Kalmykov, S Y; Petrov, V; Chvykov, V; Cummings, P; Hou, B; Maksimchuk, A; Nees, J A; Yanovsky, V; Thomas, A G R; Krushelnick, K

    2016-08-26

    Annular quasimonoenergetic electron beams with a mean energy in the range 200-400 MeV and charge on the order of several picocoulombs were generated in a laser wakefield accelerator and subsequently accelerated using a plasma afterburner in a two-stage gas cell. Generation of these beams is associated with injection occurring on the density down ramp between the stages. This well-localized injection produces a bunch of electrons performing coherent betatron oscillations in the wakefield, resulting in a significant increase in the x-ray yield. Annular electron distributions are detected in 40% of shots under optimal conditions. Simultaneous control of the pulse duration and frequency chirp enables optimization of both the energy and the energy spread of the annular beam and boosts the radiant energy per unit charge by almost an order of magnitude. These well-defined annular distributions of electrons are a promising source of high-brightness laser plasma-based x rays. PMID:27610860

  17. The QCD Phase Diagram, Equation of State, and Heavy Ion Collisions

    CERN Document Server

    Shuryak, E V

    2002-01-01

    After some historic remarks and a brief summary of recent theoretical news about the QCD phases, we turn to the issue of $freeze-out$ in heavy ion collisions. We argue that the chemical freeze-out line should actually consists of two crossing lines of different nature. We also consider some inelatic reactions which occure $after$ chemical freeze-out, emphasizing the role of overpopulation of pions. The $hydrodynamics$ (with or without hadronic afterburner) explaines SPS/RHIC data on radial and elliptic flow in unexpected details,for different particles, collision energies, and impact parameters. Apart of Equation of State (EoS), it has basically no free parameters. The EoS which describe these data best agrees quite well with the lattice predictions, with the QGP latent heat $\\Delta\\epsilon\\approx 800 Mev/fm^3$. Other phenomena at RHIC, such as ``jet quenching'' and huge ellipticity at large $p_t$, also point toward very rapid entropy production. Its mechanism remains an outstanding open problem: at the end w...

  18. Plume radiation

    Science.gov (United States)

    Dirscherl, R.

    1993-06-01

    The electromagnetic radiation originating from the exhaust plume of tactical missile motors is of outstanding importance for military system designers. Both missile- and countermeasure engineer rely on the knowledge of plume radiation properties, be it for guidance/interference control or for passive detection of adversary missiles. To allow access to plume radiation properties, they are characterized with respect to the radiation producing mechanisms like afterburning, its chemical constituents, and reactions as well as particle radiation. A classification of plume spectral emissivity regions is given due to the constraints imposed by available sensor technology and atmospheric propagation windows. Additionally assessment methods are presented that allow a common and general grouping of rocket motor properties into various categories. These methods describe state of the art experimental evaluation techniques as well as calculation codes that are most commonly used by developers of NATO countries. Dominant aspects influencing plume radiation are discussed and a standardized test technique is proposed for the assessment of plume radiation properties that include prediction procedures. These recommendations on terminology and assessment methods should be common to all employers of plume radiation. Special emphasis is put on the omnipresent need for self-protection by the passive detection of plume radiation in the ultraviolet (UV) and infrared (IR) spectral band.

  19. A unique approach to municipal waste management in Chianti, Italy

    International Nuclear Information System (INIS)

    Innovative solutions are required to manage the growing problem of disposal of municipal waste throughout the world. Recovery of energy by combustion of municipal waste has become an acceptable approach in many communities. A unique system with a capacity of 200 tons of waste per day with simultaneous production of electric power and fuel gas is currently under construction in Greve located in the famous wine region of Chianti, Italy. The refuse-derived fuel will be treated in a fluidized bed gasifier. A portion of the gas produced by the gasifier will be used to produce 6.7 MW of electric power; the remaining gas will be used as a fuel in the neighboring cement plant. The plant will be equipped with a state-of-the-art emission control system including an afterburner, a quench reactor, dry venturi and a fabric filter to minimize emissions to the atmosphere. This is the first plant in Europe to employ the fluidized bed gasifier technology on refuse-derived fuel. Design highlights of the overall plant including the air quality control system are presented in this paper

  20. Performance evaluation of a proof-of-concept 70 W internal reforming methanol fuel cell system

    Science.gov (United States)

    Avgouropoulos, G.; Schlicker, S.; Schelhaas, K.-P.; Papavasiliou, J.; Papadimitriou, K. D.; Theodorakopoulou, E.; Gourdoupi, N.; Machocki, A.; Ioannides, T.; Kallitsis, J. K.; Kolb, G.; Neophytides, S.

    2016-03-01

    A proof-of-concept 70 W Internal Reforming Methanol Fuel Cell (IRMFC) stack including Balance-of-Plant (BoP) was designed, assembled and tested. Advent TPS® high-temperature, polymer electrolyte membrane electrode assemblies were employed for fuel cell operation at 200 °C. In order to avoid phosphoric acid poisoning of the reformer, the anode electrocatalyst of each cell was indirectly adjoined, via a separation plate, to a highly active CuMnAlOx catalyst coated onto copper foam, which served as methanol reforming layer. The reformer was in-situ converting the methanol/steam feed to the required hydrogen (internal reforming concept) at 200 °C, which was readily oxidized at the anode electrodes. The operation of the IRMFC was supported through a number of BoP components consisting of a start-up subsystem (air blower, evaporator and monolithic burner), a combined afterburner/evaporator device, methanol/water supply and data acquisition units (reactants/products analysis, temperature control, flow control, system load/output control). Depending on the composition of the liquid MeOH/H2O feed streams, current densities up to 0.18 A cm-2 and power output up to 70 W could be obtained with remarkable repeatability. Specific targets for improvement of the efficiency were identified.

  1. Energy and costs scoping study for plasma pyrolysis thermal processing system

    International Nuclear Information System (INIS)

    The purpose of this study was to provide information in support of an investigation of thermal technologies as possible treatment process for buried wastes at the INEL. Material and energy balances and a cost estimate were generated for a representative plasma torch-based thermal waste treatment system operating in a pyrolysis mode. Two waste streams were selected which are representative of INEL buried wastes, large in volume, and difficult to treat by other technologies. These streams were a solidified nitrate sludge waste stream and a waste/soil mix of other buried waste components. The treatment scheme selected includes a main plasma chamber operating under pyrolyzing conditions; a plasma afterburner to provide additional residence time at high temperature to ensure complete destruction of hazardous organics; an off-gas treatment system; and a incinerator and stack to oxidize carbon monoxide to carbon dioxide and vent the clean, oxidized gases to atmosphere. The material balances generated provide materials flow and equipment duty information of sufficient accuracy to generate initial rough-order-of-magnitude (ROM) system capital and operating cost estimates for a representative plasma thermal processing system

  2. Integrated Turbine-Based Combined Cycle Dynamic Simulation Model

    Science.gov (United States)

    Haid, Daniel A.; Gamble, Eric J.

    2011-01-01

    A Turbine-Based Combined Cycle (TBCC) dynamic simulation model has been developed to demonstrate all modes of operation, including mode transition, for a turbine-based combined cycle propulsion system. The High Mach Transient Engine Cycle Code (HiTECC) is a highly integrated tool comprised of modules for modeling each of the TBCC systems whose interactions and controllability affect the TBCC propulsion system thrust and operability during its modes of operation. By structuring the simulation modeling tools around the major TBCC functional modes of operation (Dry Turbojet, Afterburning Turbojet, Transition, and Dual Mode Scramjet) the TBCC mode transition and all necessary intermediate events over its entire mission may be developed, modeled, and validated. The reported work details the use of the completed model to simulate a TBCC propulsion system as it accelerates from Mach 2.5, through mode transition, to Mach 7. The completion of this model and its subsequent use to simulate TBCC mode transition significantly extends the state-of-the-art for all TBCC modes of operation by providing a numerical simulation of the systems, interactions, and transient responses affecting the ability of the propulsion system to transition from turbine-based to ramjet/scramjet-based propulsion while maintaining constant thrust.

  3. High performance SOFC/GT combined power generation system with CO2 recovery by oxygen combustion method

    International Nuclear Information System (INIS)

    The authors newly propose and investigate two types of carbon dioxide recovering SOFC/GT combined power generation systems in which a gas turbine with carbon dioxide recycle or water vapor injection is adopted as the bottoming cycle. In these systems, fuel gas is first introduced to a SOFC, and its exhaust fuel gas is afterburned by pure oxygen. Carbon dioxide or water vapor is also injected into the combustor to reduce the combustion gas temperature. The obtained combustion gas, which is composed of only carbon dioxide and water vapor, is introduced to a gas turbine in the bottoming cycle. The exhaust gas of the gas turbine preheats the injection gas, and then, carbon dioxide is separated by only cooling and water condensation. It is made clear that the overall efficiency of the system with carbon dioxide recycle reaches 63.87% (HHV) or 70.88% (LHV), and that of the system with water vapor injection reaches 65.00% (HHV) or 72.13% (LHV). These values are sufficiently high, indicating that the proposed systems are worth further research and development

  4. Greenhouse gas emission and exergy analyses of an integrated trigeneration system driven by a solid oxide fuel cell

    International Nuclear Information System (INIS)

    Exergy and greenhouse gas emission analyses are performed for a novel trigeneration system driven by a solid oxide fuel cell (SOFC). The trigeneration system also consists of a generator-absorber heat exchanger (GAX) absorption refrigeration system and a heat exchanger to produce electrical energy, cooling and heating, respectively. Four operating cases are considered: electrical power generation, electrical power and cooling cogeneration, electrical power and heating cogeneration, and trigeneration. Attention is paid to numerous system and environmental performance parameters, namely, exergy efficiency, exergy destruction rate, and greenhouse gas emissions. A maximum enhancement of 46% is achieved in the exergy efficiency when the SOFC is used as the primary mover for the trigeneration system compared to the case when the SOFC is used as a standalone unit. The main sources of irreversibility are observed to be the air heat exchanger, the SOFC and the afterburner. The unit CO2 emission (in kg/MWh) is considerably higher for the case in which only electrical power is generated. This parameter is reduced by half when the system is operates in a trigeneration mode. - Highlights: • A novel trigeneration system driven by a solid oxide fuel cell is analyzed. • Exergy and greenhouse gas emission analyses are performed. • Four special cases are considered. • An enhancement of up to 46% is achieved in exergy efficiency. • The CO2 emission drops to a relatively low value for the tri-generation case

  5. Test Treatment of Fulfilled TBP - 12084

    International Nuclear Information System (INIS)

    At SUE SIA 'Radon' were carried out investigations and treatment of spent TBP, containing uranium with the help of the following methods: - Impregnation of porous inorganic materials by spent TBP with the subsequent inclusion into the cement compound; - Spent TBP cementation together with other LRW (inclusion of spent TBP into cement compound was 2%); - inclusion of TBP into polymeric binder Nochar, Nochar, Pacific Nuclear Solutions, Indianapolis, USA; - Impregnation of industrial porous materials with the subsequent treatment at plasma incineration facility at temperature up to 1600 deg. C. In such case takes place pyrolysis process and after-burning of organic content of spent extractant, as well as melting of its mineral content together with porous material. As a result slag incorporating radionuclides and phosphorus compounds is formed. The slag has a high chemical stability. With the help of the first method has been received cement compound with the inclusion of 20 weight % of spent TBP and during the pilot treatment about 1 m3 of TBP has been solidified. Together with other LRW over then 10 m3 of TBP has been solidified at the stationary cementation facility. Spent TBP inclusion into the polymeric binding material Nochar (N) has been carried out under laboratory conditions with a mass ratio TBP / Nochar from 1 / 1 till 20 / 1. At the plasma incineration facility has been processed about 1 m3 of spent TBP. Comparative evaluation for the suggested methods of spent TBP treatment has been made. (authors)

  6. Dioxin and furan emissions from landfill gas-fired combustion units

    International Nuclear Information System (INIS)

    The 1990 Federal Clean Air Act Amendments require the development of maximum achievable control technology standards (MACT) for sources of hazardous air pollutants, including landfill gas-fired combustion sources. The Industrial Combustion Coordinated Rulemaking (ICCR) Federal Advisory Committee is a group of stakeholders from the public and private sector whose charge is to develop recommendations for a unified set of federal toxic air emissions regulations. Specifically, the group will establish MACT standards for industrial-commercial-institutional combustion sources. The ICCR proceedings have given rise to considerable interest in potential dioxin and furan emissions from landfill gas-fired combustion units. In order to establish the potential of dioxin and furan emissions from this group of combustion sources, a world-wide literature search was conducted. A total of 22 references were evaluated. The references covered a wide range of test programs, testing methodologies and combustion equipment type. The most abundant data were for landfill gas-fired flares (shrouded and afterburners) and I.C. engines. Because of limitations in obtaining actual test reports with complete lab data and QA/QC results, and a lack of knowledge as to the exact types of waste received at the European landfills, the test data from these sources, for the purposes of this paper, are considered qualitative. The conclusion reached from review of the test data is that there is a potential for dioxin and furan emissions from landfill gas-fired combustion units, but at very low levels for well operated systems

  7. Cold start dynamics and temperature sliding observer design of an automotive SOFC APU

    Science.gov (United States)

    Lin, Po-Hsu; Hong, Che-Wun

    This paper presents a dynamic model for studying the cold start dynamics and observer design of an auxiliary power unit (APU) for automotive applications. The APU is embedded with a solid oxide fuel cell (SOFC) stack which is a quiet and pollutant-free electric generator; however, it suffers from slow start problem from ambient conditions. The SOFC APU system equips with an after-burner to accelerate the start-up transient in this research. The combustion chamber burns the residual fuel (and air) left from the SOFC to raise the exhaust temperature to preheat the SOFC stack through an energy recovery unit. Since thermal effect is the dominant factor that influences the SOFC transient and steady performance, a nonlinear real-time sliding observer for stack temperature was implemented into the system dynamics to monitor the temperature variation for future controller design. The simulation results show that a 100 W APU system in this research takes about 2 min (in theory) for start-up without considering the thermal limitation of the cell fracture.

  8. Large-Eddy Simulations of Noise Generation in Supersonic Jets at Realistic Engine Temperatures

    Science.gov (United States)

    Liu, Junhui; Corrigan, Andrew; Kailasanath, K.; Taylor, Brian

    2015-11-01

    Large-eddy simulations (LES) have been carried out to investigate the noise generation in highly heated supersonic jets at temperatures similar to those observed in high-performance jet engine exhausts. It is found that the exhaust temperature of high-performance jet engines can range from 1000K at an intermediate power to above 2000K at a maximum afterburning power. In low-temperature jets, the effects of the variation of the specific heat ratio as well as the radial temperature profile near the nozzle exit are small and are ignored, but it is not clear whether those effects can be also ignored in highly heated jets. The impact of the variation of the specific heat ratio is assessed by comparing LES results using a variable specific heat ratio with those using a constant specific heat ratio. The impact on both the flow field and the noise distributions are investigated. Because the total temperature near the nozzle wall can be substantially lower than the nozzle total temperature either due to the heating loss through the nozzle wall or due to the cooling applied near the wall, this lower wall temperature may impact the temperature in the shear layer, and thus impact the noise generation. The impact of the radial temperature profile on the jet noise generation is investigated by comparing results of lower nozzle wall temperatures with those of the adiabatic wall condition.

  9. Light-heavy-ion collisions: a window into pre-equilibrium QCD dynamics?

    International Nuclear Information System (INIS)

    Relativistic collisions of light on heavy ions (p + Au at √(s) = 7.7 GeV, p + Au, d + Au,3He + Au at √(s) = 62.4 GeV and 200 GeV and p + Pb,3He + Pb at √(s) = 5.02 TeV) are simulated using ''superSONIC'', a model that includes pre-equilibrium flow, viscous hydrodynamics and a hadronic cascade afterburner. Even though these systems have strong gradients and only consist of at most a few tens of charged particles per unit rapidity, one finds evidence that a hydrodynamic description applies to these systems. Based on these simulations, the presence of a triangular flow component in d + Au collisions at √(s) = 200 GeV is predicted to be similar in magnitude to that found in 3He + Au collisions. Furthermore, the v3(pT) ratio of 3He + Au to d + Au is found to be sensitive to the presence of pre-equilibrium flow. This would imply an experimentally accessible window into pre-equilibrium QCD dynamics using light-heavy-ion collisions. (orig.)

  10. Concept development of a Mach 4 high-speed civil transport

    Science.gov (United States)

    Domack, Christopher S.; Dollyhigh, Samuel M.; Beissner, Fred L., Jr.; Geiselhart, Karl A.; Mcgraw, Marvin E., Jr.; Shields, Elwood W.; Swanson, Edward E.

    1990-01-01

    A study was conducted to configure and analyze a 250 passenger, Mach 4 High Speed Civil Transport with a design range of 6500 n.mi. The design mission assumed an all-supersonic cruise segment and no community noise or sonic boom constraints. The study airplane was developed in order to examine the technology requirements for such a vehicle and to provide an unconstrained baseline from which to assess changes in technology levels, sonic boom limits, or community noise constraints in future studies. The propulsion, structure, and materials technologies utilized in the sizing of the study aircraft were assumed to represent a technology availability date of 2015. The study airplane was a derivative of a previously developed Mach 3 concept and utilized advanced afterburning turbojet engines and passive airframe thermal protection. Details of the configuration development, aerodynamic design, propulsion system, mass properties, and mission performance are presented. The study airplane was estimated to weigh approx. 866,000 lbs. Although an aircraft of this size is a marginally acceptable candidate to fit into the world airport infrastructure, it was concluded that the inclusion of community noise or sonic boom constraints would quickly cause the aircraft to grow beyond acceptable limits using the assumed technology levels.

  11. Plasma Sensor Measurements in Pulse Detonation Engines

    Science.gov (United States)

    Matlis, Eric; Marshall, Curtis; Corke, Thomas; Gogineni, Sivaram

    2014-11-01

    Measurements have been conducted in a pulse detonation and rotating detonation engine using a newly developed plasma sensor. This sensor relies on the novel approach of using an ac-driven, weakly-ionized electrical discharge as the main sensing element. The advantages of this approach include a native high bandwidth of 1 MHz without the need for electronic frequency compensation, a dual-mode capability that provides sensitivity to multiple flow parameters, including velocity, pressure, temperature, and gas-species, and a simple and robust design making it very cost effective. The sensor design is installation-compatible with conventional sensors commonly used in gas-turbine research such as the Kulite dynamic pressure sensor while providing much better longevity. Developmental work was performed in high temperature facilities that are relevant to the propulsion and high-speed research community. This includes tests performed in a J85 augmentor at full afterburner and pulse-detonation engines at the University of Cincinnati (UC) at temperatures approaching 2760°C (5000°F).

  12. Control of laser absorbing efficiency and proton quality by a specific double target

    Science.gov (United States)

    Yu, Q.; Gu, Y. J.; Li, X. F.; Qu, J. F.; Kong, Q.; Kawata, S.

    2016-08-01

    The micro-structured double-layer target is an efficient method to improve proton quality. However, the laser absorption efficiency is low due to strong reflection at the front surface of such targets. Moreover, the proton charge is limited by the driving laser radius. To overcome these shortcomings, a specific double-layer (SDL) target with a vacuum gap in the center of the heavy ion layer is proposed in this paper. In this specified target, the laser reflection effect is significantly weakened and the absorption and penetration efficiencies are greatly enhanced. The high-energy electrons from Breakout afterburner regime efficiently transfer their energy to the protons. Both the energy of the spectral peaks and maximum proton energy are greatly increased. The periodic structure of the longitudinal electric field makes the force applied on the protons becomes homogeneous in time average and therefore reduce the energy spread. In these SDL targets, the proton layer radius and the accelerated proton charge are not limited by the laser radius. With a larger-radius proton layer, the protons can be accelerated to high energy with small energy spread. When the proton layer radius is reduced to the laser radius, the SDL target is still an effective structure to improve the proton quality. The mechanism is proved by a series of particle-in-cell simulations.

  13. Influence of coalescence parameters on the production of protons and Helium-3 fragments

    CERN Document Server

    Li, Qingfeng; Wang, Xiaobao; Shen, Caiwan

    2016-01-01

    The time evolution of protons and $^3$He fragments from Au+Au/Pb+Pb reactions at 0.25, 2, and 20 GeV$/$nucleon is investigated with the potential version of the Ultrarelativistic Quantum Molecular Dynamics (UrQMD) model combined with the traditional coalescence afterburner. In the coalescence process, the relative distance $R_0$ and relative momentum $P_0$ are surveyed in the range of 3-4 fm and 0.25-0.35 GeV$/$c, respectively. For both clusters, a strong reversed correlation between $R_0$ and $P_0$ is seen and it is time-dependent as well. For protons, the accepted ($R_0$, $P_0$) bands lie in the time interval 30-60 fm$/$c, while for $^3$He, a longer time evolution (at about 60-90 fm$/$c) is needed. Otherwise, much smaller $R_0$ and $P_0$ values should be chosen. If we further look at the rapidity distributions from both central and semi-central collisions, it is found that the accepted [$t_{\\rm cut}, (R_0, P_0$)] assemble can provide consistent results for proton yield and collective flows especially at mid...

  14. Influence of coalescence parameters on the production of protons and Helium-3 fragments

    Science.gov (United States)

    Li, QingFeng; Wang, YongJia; Wang, XiaoBao; Shen, CaiWan

    2016-07-01

    The time evolution of protons and 3He fragments from Au+Au/Pb+Pb reactions at 0.25, 2, and 20 GeV/nucleon is investigated with the potential version of the Ultrarelativistic Quantum Molecular Dynamics (UrQMD) model combined with the traditional coalescence afterburner. In the coalescence process, the relative distance R 0 and relative momentum P 0 are surveyed in the range of 3-4 fm and 0.25-0.35 GeV/c, respectively. For both clusters, a strong reversed correlation between R 0 and P 0 is seen and it is time-dependent as well. For protons, the accepted ( R 0, P 0) bands lie in the time interval 30-60 fm/c, while for 3He, a longer time evolution (at about 60-90 fm/c) is needed. Otherwise, much smaller R 0 and P 0 values should be chosen. If we further look at the rapidity distributions from both central and semi-central collisions, it is found that the accepted [ t cut, ( R 0, P 0)] assemble can provide consistent results for proton yield and collective flows especially at mid-rapdities, while for 3He, the consistency is destroyed at both middle and projectile-target rapidities.

  15. Studying the characteristics of a 5 kW power installation on solid-oxide fuel cells with steam reforming of natural gas

    Science.gov (United States)

    Munts, V. A.; Volkova, Yu. V.; Plotnikov, N. S.; Dubinin, A. M.; Tuponogov, V. G.; Chernishev, V. A.

    2015-11-01

    The results from tests of a 5 kW power plant on solid-oxide fuel cells (SOFCs), in which natural gas is used as fuel, are presented. The installation's process circuit, the test procedure, and the analysis of the obtained results are described. The characteristics of the power plant developed by the Ural Industrial Company are investigated in four steady-state modes of its operation: with the SOFC nominal power capacity utilized by 40% (2 kW), 60% (3 kW), 90% (4.5 kW) and 110% (5.4 kW) (the peaking mode). The electrical and thermodynamic efficiencies are calculated for all operating modes, and the most efficient mode, in which the electrical efficiency reached almost 70%, is determined. The air excess coefficient and heat loss with flue gases q 2 are determined, and it is revealed that the heat loss q 5 decreases from 40 to 25% with increasing the load. Thermal balances are drawn up for the following components of the system the reformer, the SOFC battery, the catalytic burner for afterburning anode gases, the heat exchanger for heating the cathode air and the mixture of natural gas and steam, and the actual fuel utilization rates in the electrochemical generator are calculated. An equation for the resulting natural gas steam reforming reaction was obtained based on the results from calculating the equilibrium composition of reforming products for the achieved temperatures at the reformer outlet t 3.

  16. Towards Spectral Control of Laser-Driven Ion Beams Generated in the Relativistic Transparency Regime

    Science.gov (United States)

    Fernandez, Juan C.; Gautier, D. C.; Hamilton, C.; Huang, C.; Palaniyappan, S.

    2014-10-01

    Until recently, experiments on the LANL Trident laser in the relativistic transparency regime have demonstrated efficient, volumetric acceleration of the bulk target ions to high energies by the laser-plasma interaction, but with broad ion-energy distributions. That ion acceleration mechanism (Breakout Afterburner) is intrinsically capable of producing quasi-monoenergetic ion-energy distributions. However, there are processes responsible for energy spread, both during the laser-plasma interaction with present-day experimental conditions, as well as during the subsequent transport of the beam, driven by expansion of the co-moving hot-electron population. Strategies to counter such spread are discussed. Furthermore, our work to understand the recent observation of efficiently-generated, quasi-monoenergetic, ~150 MeV Al-ion beams indicates that the dynamics immediately following the laser-plasma interaction can be quite important and beneficial. It has uncovered a new strategy, i.e., using plasma-electron dynamics to increase the ion energy and to decrease its spread. This presentation thus motivates and frames two companion talks on these laser-driven Al-ion beams by Palaniyappan et al. and Huang et al. in this conference. This work is sponsored by the LANL LDRD Program.

  17. Turbulent Combustion in SDF Explosions

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, A L; Bell, J B; Beckner, V E

    2009-11-12

    A heterogeneous continuum model is proposed to describe the dispersion and combustion of an aluminum particle cloud in an explosion. It combines the gas-dynamic conservation laws for the gas phase with a continuum model for the dispersed phase, as formulated by Nigmatulin. Inter-phase mass, momentum and energy exchange are prescribed by phenomenological models. It incorporates a combustion model based on the mass conservation laws for fuel, air and products; source/sink terms are treated in the fast-chemistry limit appropriate for such gasdynamic fields, along with a model for mass transfer from the particle phase to the gas. The model takes into account both the afterburning of the detonation products of the C-4 booster with air, and the combustion of the Al particles with air. The model equations were integrated by high-order Godunov schemes for both the gas and particle phases. Numerical simulations of the explosion fields from 1.5-g Shock-Dispersed-Fuel (SDF) charge in a 6.6 liter calorimeter were used to validate the combustion model. Then the model was applied to 10-kg Al-SDF explosions in a an unconfined height-of-burst explosion. Computed pressure histories are compared with measured waveforms. Differences are caused by physical-chemical kinetic effects of particle combustion which induce ignition delays in the initial reactive blast wave and quenching of reactions at late times. Current simulations give initial insights into such modeling issues.

  18. Modelling and Simulation of a Hybrid Solid Oxide Fuel Cell Coupled with a Gas Turbine Power Plant

    Directory of Open Access Journals (Sweden)

    Luca Andreassi

    2009-09-01

    Full Text Available

    The paper presents a simulation of a hybrid solid oxide fuel cell-gas turbine (SOFC-GT power generation system fueled by natural gas. In the system considered, the unreacted fuel from a topping solid oxide fuel cell is burnt in an afterburner to feed a bottoming gas turbine and produce additional power. Combustion gas expands in the gas turbine after having preheated the inlet air and fuel and it is used to generate steam required by the reforming reactions. A novel thermodynamic model has been developed for the fuel cell and implemented into the library of a modular object-oriented Process Simulator, CAMELPro™. The relevant plant performance indicators have been analyzed to evaluate the incremental increase in efficiency brought about by the introduction of the gas turbine and heat regeneration system. Simulations were performed for different values of the main plant parameters.

    • This paper is an updated version of a paper published in the ECOS'08 proceedings. 

  19. Beyond injection: Trojan horse underdense photocathode plasma wakefield acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Hidding, B.; Rosenzweig, J. B.; Xi, Y.; O' Shea, B.; Andonian, G.; Schiller, D.; Barber, S.; Williams, O.; Pretzler, G.; Koenigstein, T.; Kleeschulte, F.; Hogan, M. J.; Litos, M.; Corde, S.; White, W. W.; Muggli, P.; Bruhwiler, D. L.; Lotov, K. [Institut fuer Laser- und Plasmaphysik, Heinrich-Heine-Universitaet Duesseldorf 40225 Duesseldorf (Germany) and Particle Beam Physics Laboratory, Department for Physics and Astronomy, UCLA (United States); Particle Beam Physics Laboratory, Department for Physics and Astronomy, UCLA (United States); Institut fuer Laser- und Plasmaphysik, Heinrich-Heine-Universitaet Duesseldorf 40225 Duesseldorf (Germany); Stanford Linear Accelerator Center (United States); Max-Planck-Institut fuer Physik, Muenchen (Germany); Tech-X Corporation, Boulder, Colorado (United States) and 1348 Redwood Ave., Boulder, Colorado 80304 (United States); Budker Institute of Nuclear Physics SB RAS, 630090, Novosibirsk (Russian Federation) and Novosibirsk State University, 630090, Novosibirsk (Russian Federation)

    2012-12-21

    An overview on the underlying principles of the hybrid plasma wakefield acceleration scheme dubbed 'Trojan Horse' acceleration is given. The concept is based on laser-controlled release of electrons directly into a particle-beam-driven plasma blowout, paving the way for controlled, shapeable electron bunches with ultralow emittance and ultrahigh brightness. Combining the virtues of a low-ionization-threshold underdense photocathode with the GV/m-scale electric fields of a practically dephasing-free beam-driven plasma blowout, this constitutes a 4th generation electron acceleration scheme. It is applicable as a beam brightness transformer for electron bunches from LWFA and PWFA systems alike. At FACET, the proof-of-concept experiment 'E-210: Trojan Horse Plasma Wakefield Acceleration' has recently been approved and is in preparation. At the same time, various LWFA facilities are currently considered to host experiments aiming at stabilizing and boosting the electron bunch output quality via a trojan horse afterburner stage. Since normalized emittance and brightness can be improved by many orders of magnitude, the scheme is an ideal candidate for light sources such as free-electron-lasers and those based on Thomson scattering and betatron radiation alike.

  20. The MOA thruster. A high performance plasma accelerator for nuclear power and propulsion applications

    International Nuclear Information System (INIS)

    More than 60 years after the late Nobel laureate Hannes Alfven had published a letter stating that oscillating magnetic fields can accelerate ionised matter via magneto-hydrodynamic interactions in a wave like fashion, the technical implementation of Alfven waves for propulsive purposes has been proposed, patented and examined for the first time by a group of inventors. The name of the concept, utilising Alfven waves to accelerate ionised matter for propulsive purposes, is MOA - Magnetic field Oscillating Amplified thruster. Alfven waves are generated by making use of two coils, one being permanently powered and serving also as magnetic nozzle, the other one being switched on and off in a cyclic way, deforming the field lines of the overall system. It is this deformation that generates Alfven waves, which are in the next step used to transport and compress the propulsive medium, in theory leading to a propulsion system with a much higher performance than any other electric propulsion system. While space propulsion is expected to be the prime application for MOA and is supported by numerous applications such as Solar and/or Nuclear Electric Propulsion or even as an 'afterburner system' for Nuclear Thermal Propulsion, other, terrestrial applications, like coating, semiconductor implantation and manufacturing as well as steel cutting can be thought of as well, making the system highly suited for a common space-terrestrial application research and utilisation strategy. This paper presents the recent developments of the MOA Thruster R and D activities at QASAR, the company in Vienna, Austria, which has been set up to further develop and test the Alfven wave technology and its applications. (author)

  1. Energy and exergy assessments of a novel trigeneration system based on a solid oxide fuel cell

    International Nuclear Information System (INIS)

    Highlights: • Energy and exergy assessments are reported of a novel trigeneration system. • The influences of two significant SOFC parameters are investigated. • Trigeneration system’s efficiency is higher than that of the SOFC by up to 33%. • The highest exergy destruction occurs in the air heat exchanger. - Abstract: Energy and exergy assessments are reported of a novel trigeneration system based on a solid oxide fuel cell (SOFC), for steady-state operation and using a zero-dimensional approach. The trigeneration system also includes a generator-absorber heat exchanger for cooling and a heat exchanger for the heating process. The influences of two significant SOFC parameters (current density and inlet flow temperature) on several variables are investigated. The results show that the energy efficiency is a minimum of 33% higher when using the trigeneration system compared with the SOFC power cycle. In addition, the maximum energy efficiencies are found to be 79% for the trigeneration system, 69% for the heating cogeneration, 58% for cooling cogeneration and 46% for electricity production. Moreover, the highest trigeneration exergy efficiency is almost 47% under the given conditions. It is also shown that, as SOFC current density increases, the exergy efficiencies decrease for the power cycle, cooling cogeneration, heating cogeneration and trigeneration. As current density increases, the trigeneration energy and exergy efficiencies decrease, and an optimal current density is observed to exist at which the net electrical power is a maximum. As SOFC inlet flow temperature increases, the trigeneration energy and exergy efficiencies and net electrical power increase to a peak and then decrease. The main exergy destructions occur in the air heat exchanger, the SOFC and the afterburner

  2. MOA: Magnetic Field Oscillating Amplified Thruster and its Application for Nuclear Electric and Thermal Propulsion

    International Nuclear Information System (INIS)

    More than 60 years after the later Nobel laureate Hannes Alfven had published a letter stating that oscillating magnetic fields can accelerate ionised matter via magneto-hydrodynamic interactions in a wave like fashion, the technical implementation of Alfven waves for propulsive purposes has been proposed, patented and examined for the first time by a group of inventors. The name of the concept, utilising Alfven waves to accelerate ionised matter for propulsive purposes, is MOA - Magnetic field Oscillating Amplified thruster. Alfven waves are generated by making use of two coils, one being permanently powered and serving also as magnetic nozzle, the other one being switched on and off in a cyclic way, deforming the field lines of the overall system. It is this deformation that generates Alfven waves, which are in the next step used to transport and compress the propulsive medium, in theory leading to a propulsion system with a much higher performance than any other electric propulsion system. Based on computer simulations, which were conducted to get a first estimate on the performance of the system, MOA is a highly flexible propulsion system, whose performance parameters might easily be adapted, by changing the mass flow and/or the power level. As such the system is capable to deliver a maximum specific impulse of 13116 s (12.87 mN) at a power level of 11.16 kW, using Xe as propellant, but can also be attuned to provide a thrust of 236.5 mN (2411 s) at 6.15 kW of power. While space propulsion is expected to be the prime application for MOA and is supported by numerous applications such as Solar and/or Nuclear Electric Propulsion or even as an 'afterburner system' for Nuclear Thermal Propulsion, other terrestrial applications can be thought of as well, making the system highly suited for a common space-terrestrial application research and utilisation strategy. (authors)

  3. Solidification experiments of high-level liquid waste, (1)

    International Nuclear Information System (INIS)

    Many processes to solidify into glass, ceramics, or metal composites can be expected to solidify high-level liquid wastes, and the calcination is considered to be one of the steps in each process. A laboratory scale fluidized-bed calciner has been constructed to study the feasibility of the calcination process. The calcined products carried with off gas are caught by cyclones and collected in hoppers. The calcined products are also taken out from overflow line by changing the operating conditions. Off-gas leaving the cyclones is washed and cooled in the spray quench tower, then cooled again in the condenser, and released through the demister, filter and blower. The main purpose of this off-gas treatment system is to remove acid fume from off-gas. The calciner is made of stainless steel tube of 4 in diameter, and is designed to treat waste solution at the rate of 1.0 l/hr. Heating is carried out by means of an electroresistance heater up to 500 deg. C, and in-bed combustion of kerosene is performed at the temperature above 500 deg. C. The calciner was operated by using 5 N nitric acid instead of synthetic wastes. Ignition and combustion of kerosene were stable in the fluidized bed heated up to 650 deg. C. The temperature was able to be controlled within +-5 deg. C of the target by controlling the feeding rate of kerosene. There was no substantial trouble about the equipment in this test operation. But in case of very low feeding rate, the time lag in ignition and subsequent after-burning phenomenon were observed. (Kobatake, H.)

  4. INVESTIGATION OF FUEL CHEMISTRY AND BED PERFORMANCE IN A FLUIDIZED BED BLACK LIQUOR STEAM REFORMER

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Whitty

    2003-12-01

    The University of Utah project ''Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer'' (DOE award number DE-FC26-02NT41490) was developed in response to a solicitation for projects to provide technical support for black liquor and biomass gasification. The primary focus of the project is to provide support for a DOE-sponsored demonstration of MTCI's black liquor steam reforming technology at Georgia-Pacific's paper mill in Big Island, Virginia. A more overarching goal is to improve the understanding of phenomena that take place during low temperature black liquor gasification. This is achieved through five complementary technical tasks: (1) construction of a fluidized bed black liquor gasification test system, (2) investigation of bed performance, (3) evaluation of product gas quality, (4) black liquor conversion analysis and modeling and (5) computational modeling of the Big Island gasifier. Four experimental devices have been constructed under this project. The largest facility, which is the heart of the experimental effort, is a pressurized fluidized bed gasification test system. The system is designed to be able to reproduce conditions near the black liquor injectors in the Big Island steam reformer, so the behavior of black liquor pyrolysis and char gasification can be quantified in a representative environment. The gasification test system comprises five subsystems: steam generation and superheating, black liquor feed, fluidized bed reactor, afterburner for syngas combustion and a flue gas cooler/condenser. The three-story system is located at University of Utah's Industrial Combustion and Gasification Research Facility, and all resources there are available to support the research.

  5. Flame stabilization by a plasma driven radical jet in a high speed flow

    Science.gov (United States)

    Choi, Woong-Sik

    In current afterburners combustion is stabilized by the high temperature, recirculating region behind bluff body flame holders, such as V-gutters. Blocking the high speed flow with bluff bodies causes a significant pressure drop, and heating the flame holder by the hot combustion product causes a thermal signature, which is a critical problem in a military jet. To reduce these problems, ignition methods using a high frequency (HF) spark discharge, or a radical jet generator (RJG) were developed. The HF discharge ignited and stabilized a flame successfully in a premixed methane-air flow. The electrical power consumption was very small compared to the combustion heat release, as long as the operating velocity was relatively low. However, a theoretical study showed that the ratio of the electrical power consumption to the heat generation by the stabilized flame increases rapidly with increasing flow velocity. For flame stabilization in a high velocity flow, the developed RJG showed much better performance than direct exposure to a plasma. The present study investigated the characteristics of a radical jet produced in a RJG and injected into a main combustor. The limits of flame stabilization by this jet was measured experimentally, and compared to those of bluff body flame holders. The flame holding performance of the radical jet was also experimentally compared to that of a thermal jet. The effect of radicals on flame stabilization was examined using CHEMKIN, and the limit of flame stabilization by the radical jet was estimated for a simple flow configuration using an approximate solution. The results suggest that the reduction of local spontaneous ignition delay time by active species in the radical jet and the longer length of a typical radical jet compared to the dimension of the recirculation zone behind a bluff body increases the maximum velocity at which a flame can be stabilized.

  6. Treatment of low-level radioactive waste by plasma. A proven technology?

    International Nuclear Information System (INIS)

    Large amounts of actual and historical low level radioactive waste, with varying characteristics, are stored and generated from the operation and maintenance of nuclear power plants, the nuclear fuel cycle, research laboratories, pharmaceutical and medical facilities. Virtual all of these waste streams can be treated by the plasma technology resulting in a final product free of organics, liquids and moisture, and meeting without a doubt the acceptance criteria for safe storage and disposal. The plasma is a highly desirable heat source. Its high temperature of up to 10.000degC can treat the radioactive waste as is. The inorganic materials are melted into a glassy slag, containing most of the radioactive isotopes, while the organic material is vaporized into a syngas and subsequently oxidized in an afterburner. This technology is very suitable for historical waste containing mixtures of inorganic, organic, liquids, sludge, etc, with almost no waste preparation and with minimal risk for radioactive contamination and exposure. Plasma technology offers a high volume waste reduction factor (VRF) that minimizes the volume and overall costs of waste storage and disposal. In addition, as plasma technology can recondition previously conditioned waste packages that no longer meet the present acceptance criteria for final disposal, it offers a solution to the growing demand for improved quality of final waste forms. As such, plasma technology is of great value, not just to waste producers but to future generations as well. This paper describes further the principles of plasma, the different waste feed systems, off-gas treatment, operational experience and future plasma plants. (author)

  7. Research on hypersonic aircraft using pre-cooled turbojet engines

    Science.gov (United States)

    Taguchi, Hideyuki; Kobayashi, Hiroaki; Kojima, Takayuki; Ueno, Atsushi; Imamura, Shunsuke; Hongoh, Motoyuki; Harada, Kenya

    2012-04-01

    Systems analysis of a Mach 5 class hypersonic aircraft is performed. The aircraft can fly across the Pacific Ocean in 2 h. A multidisciplinary optimization program for aerodynamics, structure, propulsion, and trajectory is used in the analysis. The result of each element model is improved using higher accuracy analysis tools. The aerodynamic performance of the hypersonic aircraft is examined through hypersonic wind tunnel tests. A thermal management system based on the data of the wind tunnel tests is proposed. A pre-cooled turbojet engine is adopted as the propulsion system for the hypersonic aircraft. The engine can be operated continuously from take-off to Mach 5. This engine uses a pre-cooling cycle using cryogenic liquid hydrogen. The high temperature inlet air of hypersonic flight would be cooled by the same liquid hydrogen used as fuel. The engine is tested under sea level static conditions. The engine is installed on a flight test vehicle. Both liquid hydrogen fuel and gaseous hydrogen fuel are supplied to the engine from a tank and cylinders installed within the vehicle. The designed operation of major components of the engine is confirmed. A large amount of liquid hydrogen is supplied to the pre-cooler in order to make its performance sufficient for Mach 5 flight. Thus, fuel rich combustion is adopted at the afterburner. The experiments are carried out under the conditions that the engine is mounted upon an experimental airframe with both set up either horizontally or vertically. As a result, the operating procedure of the pre-cooled turbojet engine is demonstrated.

  8. Preliminary MIPCC Enhanced F-4 and F-15 Preformance Characteristics for a First Stage Reusable Launch Vehicle

    Science.gov (United States)

    Kloesel, Kurt J.; Clark, Casie M.

    2013-01-01

    Performance increases in turbojet engines can theoretically be achieved through Mass Injection Pre-Compressor Cooling (MIPCC), a process involving injecting water or oxidizer or both into an afterburning turbojet engine. The injection of water results in pre-compressor cooling, allowing the propulsion system to operate at high altitudes and Mach numbers. In this way, a MIPCC-enhanced turbojet engine could be used to power the first stage of a reusable launch vehicle or be integrated into an existing aircraft that could launch a 100-lbm payload to a reference 100-nm altitude orbit at 28 deg inclination. The two possible candidates for MIPCC flight demonstration that are evaluated in this study are the F-4 Phantom II airplane and the F-15 Eagle airplane (both of McDonnell Douglas, now The Boeing Company, Chicago, Illinois), powered by two General Electric Company (Fairfield, Connecticut) J79 engines and two Pratt & Whitney (East Hartford, Connecticut) F100-PW-100 engines, respectively. This paper presents a conceptual discussion of the theoretical performance of each of these aircraft using MIPCC propulsion techniques. Trajectory studies were completed with the Optimal Trajectories by Implicit Simulation (OTIS) software (NASA Glenn Research Center, Cleveland, Ohio) for a standard F-4 airplane and a standard F-15 airplane. Standard aircraft simulation models were constructed, and the thrust in each was altered in accordance with estimated MIPCC performance characteristics. The MIPCC and production aircraft model results were then reviewed to assess the feasibility of a MIPCC-enhanced propulsion system for use as a first-stage reusable launch vehicle; it was determined that the MIPCC-enhanced F-15 model showed a significant performance advantage over the MIPCC-enhanced F-4 model.

  9. Preliminary MIPCC Enhanced F-4 and F-15 Performance Characteristics for a First Stage Reusable Launch Vehicle

    Science.gov (United States)

    Kloesel, Kurt J.

    2013-01-01

    Performance increases in turbojet engines can theoretically be achieved through Mass Injection Pre-Compressor Cooling (MIPCC), a process involving injecting water or oxidizer or both into an afterburning turbojet engine. The injection of water results in pre-compressor cooling, allowing the propulsion system to operate at high altitudes and Mach numbers. In this way, a MIPCC-enhanced turbojet engine could be used to power the first stage of a reusable launch vehicle or be integrated into an existing aircraft that could launch a 100-lbm payload to a reference 100-nm altitude orbit at 28 deg inclination. The two possible candidates for MIPCC flight demonstration that are evaluated in this study are the F-4 Phantom II airplane and the F-15 Eagle airplane (both of McDonnell Douglas, now The Boeing Company, Chicago, Illinois), powered by two General Electric Company (Fairfield, Connecticut) J79 engines and two Pratt & Whitney (East Hartford, Connecticut) F100-PW-100 engines, respectively. This paper presents a conceptual discussion of the theoretical performance of each of these aircraft using MIPCC propulsion techniques. Trajectory studies were completed with the Optimal Trajectories by Implicit Simulation (OTIS) software (NASA Glenn Research Center, Cleveland, Ohio) for a standard F-4 airplane and a standard F-15 airplane. Standard aircraft simulation models were constructed, and the thrust in each was altered in accordance with estimated MIPCC performance characteristics. The MIPCC and production aircraft model results were then reviewed to assess the feasibility of a MIPCC-enhanced propulsion system for use as a first-stage reusable launch vehicle; it was determined that the MIPCC-enhanced F-15 model showed a significant performance advantage over the MIPCC-enhanced F-4 model.

  10. Remediation of a 115,000-gallon petroleum pipeline leak

    International Nuclear Information System (INIS)

    A rupture in a buried petroleum pipeline in June, 1988 released 115,000 gallons of diesel fuel, contaminating soil and ground water at a site in Milwaukee, Wisconsin. Emergency and interim response actions resulted in the recovery of over 70,000 gallons of product from the ground surface, a nearby creek, and recovery trenches. Based on the results of a contamination assessment, the most cost effective and technically feasible remedial alternative included low temperature thermal desorption for treatment of the impacted soils, and recovery of impacted ground water with discharge to a sanitary sewer. The implementation of the thermal desorption process was the first application of its type in the State of Wisconsin. Approximately 10,000 cubic yards of soil, with a total petroleum hydrocarbon (TPH) concentration of up to 24,000 parts per million (ppm), was treated at the site using the thermal desorption system. Using a feed rate of approximately 20 tons per hour, the impacted unconsolidated materials, varying in composition from gravelly sand to silty clay, were heated to 400 to 500 degrees F in a propane-fired rotary kiln. In the process, petroleum was vaporized off the soils and then completely oxidized at 1450 degrees F in an afterburner. After processing, the soil was replaced in the excavation with a TPH concentration of less than 10 ppm. Impacted ground water is still being treated at the site using a 225-foot long interception trench. An automated pumping system recovers slightly impacted ground water which is subsequently discharged to the sanitary sewer. Residual free product is collected from the water surface manually using oil skimming devices. Dissolved volatile organic compounds (VOCs) total less than 5 ppm; therefore no treatment is required prior to discharge to the sewer. Pending approval of a permit application, discharge will be to a nearby stream

  11. Avoidance of superheater corrosion by external overheating; Vermeidung von Ueberhitzerkorrosion durch externe Ueberhitzung

    Energy Technology Data Exchange (ETDEWEB)

    Schu, R. [EcoEnergy, Walkenried (Germany)

    2007-07-01

    In the contribution under consideration it is proven that by adapted processing and plant circuit of the technologies available at the market a substantial increase of the energy efficiency of refuse incineration plants is possible. A processing with under-stoichiometric incineration on the rust with afterburning of the gaseous fuel in a repeated air staggering does not only lower the air number on < 1,25, but also substantially reduce the emissions and minimize the electrical internal requirement as well as the corrosion. Beside this, a remainder utilization of heat of the flue gases is only made possible by preliminary combustion air heating and extension of the fuel volume from at present max. 18,000 kJ/kg for conventional rust heating installations on 32,000 kJ/kg. The results clearly show that by an optimal plant circuit with external overheating in the BiFuelCycle procedure in connection with the optimized processing the energy efficiency can be increased by waste treatment plants by 30% to 60%. However, in strong measure these possibilities depend on the readiness of the operators, technology suppliers and politicians to take the path begun with the AVI Amsterdam and other plants to more energy efficient handling with ''the urban Resources ''. With the mentioned possibilities for the external overheating not only the technology suppliers for the steam generation, but above all the turbine manufacturers are demanded to develop highly efficient highly efficient turbines with high steam parameters and repeated condensate and feed water preliminary heating also in the lower capacity range < 50 MW{sub e}l.

  12. Development of nuclear fuel cycle technologies - bases of long-term provision of fuel and environmental safety of nuclear power

    International Nuclear Information System (INIS)

    To-day nuclear power is one of the options, however, to-morrow it may become the main source of the energy, thus, providing for the stable economic development for the long time to come. The availability of the large-scale nuclear power in the foreseeable future is governed by not only the safe operation of nuclear power plants (NPP) but also by the environmentally safe management of spent nuclear fuel, radioactive waste conditioning and long-term storage. More emphasis is to be placed to the closing of the fuel cycle in view of substantial quantities of spent nuclear fuel arisings. The once-through fuel cycle that is cost effective at the moment cannot be considered to be environmentally safe even for the middle term since the substantial build-up of spent nuclear fuel containing thousands of tons Pu will require the resolution of the safe management problem in the nearest future and is absolutely unjustified in terms of moral ethics as a transfer of the responsibility to future generations. The minimization of radioactive waste arisings and its radioactivity is only feasible with the closed fuel cycle put into practice and some actinides and long-lived fission radionuclides burnt out. The key issues in providing the environmentally safe fuel cycle are efficient processes of producing fuel for NPP, radionuclide after-burning included, a long-term spent nuclear fuel storage and reprocessing as well as radioactive waste management. The paper deals with the problems inherent in producing fuel for NPP with a view for the closed fuel cycle. Also discussed are options of the fuel cycle, its effectiveness and environmental safety with improvements in technologies of spent nuclear fuel reprocessing and long-lived radionuclide partitioning. (authors)

  13. Advanced air staging techniques to improve fuel flexibility, reliability and emissions in fluidized bed co-combustion

    Energy Technology Data Exchange (ETDEWEB)

    Aamand, Lars-Erik; Leckner, Bo [Chalmers Technical Univ., Goeteborg (Sweden); Luecke, Karsten; Werther, Joachim [Technical Univ. of Hamburg-Harburg (Germany)

    2001-12-01

    A joint research project between the Technical University of Hamburg-Harburg and Chalmers Technical University. For operation under co-combustion the following results should be considered: The high ash content of the sewage sludge results in significantly increased ash flows. Although high alkali metal concentrations are found in the sewage sludge ash, no critical concentrations were reached and tendencies to fouling were not observed. The trace metal input rises with increased sludge fraction. However, emissions of metal compounds were well below legal limits. The trace metals tend to accumulate on the fly ash. In general, very low fuel nitrogen conversions to NO and N{sub 2}O of 2 - 4 % are achievable. With coal as a base fuel alternative air staging with secondary air supply after solids separation attains even lower NO emissions than normal staging without strongly affecting CO and SO{sub 2} emissions. Alternative staging also reduces N{sub 2}O emissions. An optimum for the excess air ratio in the riser of 1.05 was found for a total excess air ratio of 1.2. The higher the volatile content of the fuel is, the less effective the NO reduction due to air staging becomes. The measurements suggest that the optimum gas residence time regarding the emissions in CFB combustors is around 6 to 7 s. These times are achieved in commercial scale plants due to their large cyclones that perhaps partly can replace a large afterburner chamber. The circulating fluidized bed boiler can be operated in a very flexible way with various fuel mixtures up to an energy fraction of sludge of 25% without exceeding legal emission limits.

  14. Possible operation of the European XFEL with ultra-low emittance beams

    International Nuclear Information System (INIS)

    Recent successful lasing of the Linac Coherent Light Source (LCLS) in the hard x-ray regime and the experimental demonstration of a possibility to produce low-charge bunches with ultra-small normalized emittance have lead to the discussions on optimistic scenarios of operation of the European XFEL. In this paper we consider new options that make use of low-emittance beams, a relatively high beam energy, tunable-gap undulators, and a multibunch capability of this facility. We study the possibility of operation of a spontaneous radiator (combining two of them, U1 and U2, in one beamline) in the SASE mode in the designed photon energy range 20-90 keV and show that it becomes possible with ultra-low emittance electron beams similar to those generated in LCLS. As an additional attractive option we consider the generation of powerful soft X-ray and VUV radiation by the same electron bunch for pump-probe experiments, making use of recently invented compact afterburner scheme. We also propose a betatron switcher as a simple, cheap, and robust solution for multi-color operation of SASE1 and SASE2 undulators, allowing to generate 2 to 5 X-ray beams of different independent colors from each of these undulators for simultaneous multi-user operation. We describe a scheme for pump-probe experiments, based on a production of two different colors by two closely spaced electron bunches (produced in photoinjector) with the help of a very fast betatron switcher. Finally, we discuss how without significant modifications of the layout the European XFEL can become a unique facility that continuously covers with powerful, coherent radiation a part of the electromagnetic spectrum from far infrared to gamma-rays. (orig.)

  15. Measurements of Unexpected Ozone Loss in a Nighttime Space Shuttle Exhaust Plume: Implications for Geo-Engineering Projects

    Science.gov (United States)

    Avallone, L. M.; Kalnajs, L. E.; Toohey, D. W.; Ross, M. N.

    2008-12-01

    Measurements of ozone, carbon dioxide and particulate water were made in the nighttime exhaust plume of the Space Shuttle (STS-116) on 9 December 2006 as part of the PUMA/WAVE campaign (Plume Ultrafast Measurements Acquisition/WB-57F Ascent Video Experiment). The launch took place from Kennedy Space Center at 8:47 pm (local time) on a moonless night and the WB-57F aircraft penetrated the shuttle plume approximately 25 minutes after launch in the lowermost stratosphere. Ozone loss is not predicted to occur in a nighttime Space Shuttle plume since it has long been assumed that the main ozone loss mechanism associated with rocket emissions requires solar photolysis to drive several chlorine-based catalytic cycles. However, the nighttime in situ observations show an unexpected loss of ozone of approximately 250 ppb in the evolving exhaust plume, inconsistent with model predictions. We will present the observations of the shuttle exhaust plume composition and the results of photochemical models of the Space Shuttle plume. We will show that models constrained by known rocket emission kinetics, including afterburning, and reasonable plume dispersion rates, based on the CO2 observations, cannot explain the observed ozone loss. We will propose potential explanations for the lack of agreement between models and the observations, and will discuss the implications of these explanations for our understanding of the composition of rocket emissions. We will describe the potential consequences of the observed ozone loss for long-term damage to the stratospheric ozone layer should geo-engineering projects based on rocket launches be employed.

  16. Circular polarization control for the LCLS baseline in the soft X-ray regime

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2010-12-15

    The LCLS baseline includes a planar undulator system, which produces intense linearly polarized light in the wavelength range 0.15-1.5 nm. In the soft X-ray wavelength region polarization control from linear to circular is highly desirable for studying ultrafast magnetic phenomena and material science issues. Several schemes using helical undulators have been discussed in the context of the LCLS. One consists in replacing three of the last planar undulator segments by helical (APPLE III) ones. A second proposal, the 2nd harmonic helical afterburner, is based on the use of short, crossed undulators tuned to the second harmonic. This last scheme is expected to be the better one. Its advantages are a high (over 90%) and stable degree of circular polarization and a low cost. Its disadvantage is a small output power (1% of the power at the fundamental harmonic) and a narrow wavelength range. We propose a novel method to generate 10 GW level power at the fundamental harmonic with 99% degree of circular polarization from the LCLS baseline. Its merits are low cost, simplicity and easy implementation. In the option presented here, the microbunching of the planar undulator is used too. After the baseline undulator, the electron beam is sent through a 40 m long straight section, and subsequently passes through a short helical (APPLE II) radiator. In this case the microbunch structure is easily preserved, and intense coherent radiation is emitted in the helical radiator. The background radiation from the baseline undulator can be easily suppressed by letting radiation and electron beamthrough horizontal and vertical slits upstream the helical radiator, where the radiation spot size is about ten times larger than the electron bunch transverse size. Using thin Beryllium foils for the slits the divergence of the electron beam halo will increase by Coulomb scattering, but the beam will propagate through the setup without electron losses. The applicability of our method is not

  17. Recent developments of the MOA thruster, a high performance plasma accelerator for nuclear power and propulsion applications

    International Nuclear Information System (INIS)

    More than 60 years after the late Nobel laureate Hannes Alfven had published a letter stating that oscillating magnetic fields can accelerate ionised matter via magneto-hydrodynamic interactions in a wave like fashion, the technical implementation of Alfven waves for propulsive purposes has been proposed, patented and examined for the first time by a group of inventors. The name of the concept, utilising Alfven waves to accelerate ionised matter for propulsive purposes, is MOA -Magnetic field Oscillating Amplified thruster. Alfven waves are generated by making use of two coils, one being permanently powered and serving also as magnetic nozzle, the other one being switched on and off in a cyclic way, deforming the field lines of the overall system. It is this deformation that generates Alfven waves, which are in the next step used to transport and compress the propulsive medium, in theory leading to a propulsion system with a much higher performance than any other electric propulsion system. Based on computer simulations, which were conducted to get a first estimate on the performance of the system, MOA is a highly flexible propulsion system, whose performance parameters might easily be adapted, by changing the mass flow and/or the power level. As such the system is capable to deliver a maximum specific impulse of 13116 s (12.87 mN) at a power level of 11.16 kW, using Xe as propellant, but can also be attuned to provide a thrust of 236.5 mN (2411 s) at 6.15 kW of power. While space propulsion is expected to be the prime application for MOA and is supported by numerous applications such as Solar and/or Nuclear Electric Propulsion or even as an 'afterburner system' for Nuclear Thermal Propulsion, other terrestrial applications can be thought of as well, making the system highly suited for a common space-terrestrial application research and utilization strategy. This paper presents the recent developments of the MOA Thruster R and D activities at QASAR, the company in

  18. Nuclear Thermal Propulsion (NTP): A Proven Growth Technology for Human NEO/Mars Exploration Missions

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2012-01-01

    The nuclear thermal rocket (NTR) represents the next "evolutionary step" in high performance rocket propulsion. Unlike conventional chemical rockets that produce their energy through combustion, the NTR derives its energy from fission of Uranium-235 atoms contained within fuel elements that comprise the engine s reactor core. Using an "expander" cycle for turbopump drive power, hydrogen propellant is raised to a high pressure and pumped through coolant channels in the fuel elements where it is superheated then expanded out a supersonic nozzle to generate high thrust. By using hydrogen for both the reactor coolant and propellant, the NTR can achieve specific impulse (Isp) values of 900 seconds (s) or more - twice that of today s best chemical rockets. From 1955 - 1972, twenty rocket reactors were designed, built and ground tested in the Rover and NERVA (Nuclear Engine for Rocket Vehicle Applications) programs. These programs demonstrated: (1) high temperature carbide-based nuclear fuels; (2) a wide range of thrust levels; (3) sustained engine operation; (4) accumulated lifetime at full power; and (5) restart capability - all the requirements needed for a human Mars mission. Ceramic metal "cermet" fuel was pursued as well, as a backup option. The NTR also has significant "evolution and growth" capability. Configured as a "bimodal" system, it can generate its own electrical power to support spacecraft operational needs. Adding an oxygen "afterburner" nozzle introduces a variable thrust and Isp capability and allows bipropellant operation. In NASA s recent Mars Design Reference Architecture (DRA) 5.0 study, the NTR was selected as the preferred propulsion option because of its proven technology, higher performance, lower launch mass, versatile vehicle design, simple assembly, and growth potential. In contrast to other advanced propulsion options, no large technology scale-ups are required for NTP either. In fact, the smallest engine tested during the Rover program

  19. Numerical simulation of the unsteady heat-transfer in a turbine-rotor in consideration of hot-spot effects. Final report; AG-Turbo-Vorhaben 1.324: Numerische Simulation des instationaeren Waermeuebergangs an einem Turbinenrotor unter Einschluss von Heissstellen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Nuernberger, D.

    2001-07-01

    In this research project the influence of hot-gas effects, so called hot-spots, to the thermal load of high pressure turbine rotors was investigated in. Generally the total process efficiency can massively be improved by an increase of the temperature level at turbine entrance. However the temperatures of modern gas turbines can only be realized by efficient cooling techniques of the turbine blade materials. Furthermore the turbine stages close to the combustion chamber are exposed to an additional thermal loading due to the so called hot-spots. These streaks of unburned fuel entering the first turbine passages can cause a dramatic increase of local temperature in their afterburning process. For an optimized thermal design a detailed knowledge of these hot-streaks and their interaction with the unsteady flow through the turbomachinery flow is necessary. With this research program time accurate numerical investigations were performed to analyze the interaction process between the occurring hot gases and the high loaded turbine rotors. The numerical simulations started with fundamental investigation of the hot-spot and heat transfer modeling. Based on these developements threedimensional time accurate simulations for a realistic high pressure turbine configuration were performed. Herein the unsteady mechanisms of the hot gases and their influence on the heat transfer of the blade material was analyzed. In total the hot-streaks lead to a massiv increase of the thermal loading mainly on the pressure sides. (orig.) [German] Im Rahmen dieses Forschungsvorhabens wurden der Einfluss von Heissgaseffekten, sogenannten Hot-Spots auf die thermische Belastung von Turbinenrotoren numerisch untersucht. Gemeinhin sind die sehr hohen Turbineneintrittstemperaturen, deren Erhoehung einen wesentlichen Beitrag zur Verbesserung des gesamten Prozesswirkungsgrades leisten, nur durch effektive Kuehlungsmassnahmen der Schaufelwerkstoffe realisierbar. Zudem erfahren diese unmittelbar dem

  20. New photon science and extreme field physics: volumetric interaction of ultra-intense laser pulses with over-dense targets

    Energy Technology Data Exchange (ETDEWEB)

    Hegelich, Bjorn M [Los Alamos National Laboratory

    2010-11-24

    The constantly improving capabilities of ultra-high power lasers are enabling interactions of matter with ever extremer fields. As both the on target intensity and the laser contrast are increasing, new physics regimes are becoming accessible and new effects materialize, which in turn enable a host of applications. A first example is the realization of interactions in the transparent-overdense regime (TOR), which is reached by interacting a highly relativistic (a{sub 0} > 10), ultra high contrast laser pulse with a solid density, nanometer target. Here, a still overdense target is turned transparent to the laser by the relativistic mass increase of the electrons, increasing the skin depth beyond the target thickness and thus enabling volumetric interaction of the laser with the entire target instead of only a small interaction region at the critical density surface. This increases the energy coupling, enabling a range of effects, including relativistic optics and pulse shaping, mono-energetic electron acceleration, highly efficient ion acceleration in the break-out afterburner regime, the generation of relativistic and forward directed surface harmonics. In this talk we will show the theoretical framework for this regime, explored by multi-D, high resolution and high density PIC simulations as well as analytic theory and present measurements and experimental demonstrations of direct relativistic optics, relativistic HHG, electron acceleration, and BOA ion acceleration in the transparent overdense regime. These effects can in turn be used in a host of applications including laser pulse shaping, ICF diagnostics, coherent x-ray sources, and ion sources for fast ignition (IFI), homeland security applications and medical therapy. This host of applications already makes transparent-overdense regime one of general interest, a situation reinforced by the fact that the TOR target undergoes an extremely wide HEDP parameter space during interaction ranging from WDM conditions

  1. Nuclear Thermal Rocket (Ntr) Propulsion: A Proven Game-Changing Technology for Future Human Exploration Missions

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2012-01-01

    The NTR represents the next evolutionary step in high performance rocket propulsion. It generates high thrust and has a specific impulse (Isp) of approx.900 seconds (s) or more V twice that of today s best chemical rockets. The technology is also proven. During the previous Rover and NERVA (Nuclear Engine for Rocket Vehicle Applications) nuclear rocket programs, 20 rocket reactors were designed, built and ground tested. These tests demonstrated: (1) a wide range of thrust; (2) high temperature carbide-based nuclear fuel; (3) sustained engine operation; (4) accumulated lifetime; and (5) restart capability V all the requirements needed for a human mission to Mars. Ceramic metal cermet fuel was also pursued, as a backup option. The NTR also has significant growth and evolution potential. Configured as a bimodal system, it can generate electrical power for the spacecraft. Adding an oxygen afterburner nozzle introduces a variable thrust and Isp capability and allows bipropellant operation. In NASA s recent Mars Design Reference Architecture (DRA) 5.0 study, the NTR was selected as the preferred propulsion option because of its proven technology, higher performance, lower launch mass, simple assembly and mission operations. In contrast to other advanced propulsion options, NTP requires no large technology scale-ups. In fact, the smallest engine tested during the Rover program V the 25,000 lbf (25 klbf) Pewee engine is sufficient for human Mars missions when used in a clustered engine arrangement. The Copernicus crewed spacecraft design developed in DRA 5.0 has significant capability and a human exploration strategy is outlined here that uses Copernicus and its key components for precursor near Earth asteroid (NEA) and Mars orbital missions prior to a Mars landing mission. Initially, the basic Copernicus vehicle can enable reusable 1-year round trip human missions to candidate NEAs like 1991 JW and Apophis in the late 2020 s to check out vehicle systems. Afterwards, the

  2. Atmospheric environmental implications of propulsion systems

    Science.gov (United States)

    Mcdonald, Allan J.; Bennett, Robert R.

    1995-01-01

    Three independent studies have been conducted for assessing the impact of rocket launches on the earth's environment. These studies have addressed issues of acid rain in the troposphere, ozone depletion in the stratosphere, toxicity of chemical rocket exhaust products, and the potential impact on global warming from carbon dioxide emissions from rocket launches. Local, regional, and global impact assessments were examined and compared with both natural sources and anthropogenic sources of known atmospheric pollutants with the following conclusions: (1) Neither solid nor liquid rocket launches have a significant impact on the earth's global environment, and there is no real significant difference between the two. (2) Regional and local atmospheric impacts are more significant than global impacts, but quickly return to normal background conditions within a few hours after launch. And (3) vastly increased space launch activities equivalent to 50 U.S. Space Shuttles or 50 Russian Energia launches per year would not significantly impact these conclusions. However, these assessments, for the most part, are based upon homogeneous gas phase chemistry analysis; heterogeneous chemistry from exhaust particulates, such as aluminum oxide, ice contrails, soot, etc., and the influence of plume temperature and afterburning of fuel-rich exhaust products, need to be further addressed. It was the consensus of these studies that computer modeling of interactive plume chemistry with the atmosphere needs to be improved and computer models need to be verified with experimental data. Rocket exhaust plume chemistry can be modified with propellant reformulation and changes in operating conditions, but, based upon the current state of knowledge, it does not appear that significant environmental improvements from propellant formulation changes can be made or are warranted. Flight safety, reliability, and cost improvements are paramount for any new rocket system, and these important aspects

  3. Ion acceleration from relativistic laser nano-target interaction

    International Nuclear Information System (INIS)

    Laser-ion acceleration has been of particular interest over the last decade for fundamental as well as applied sciences. Remarkable progress has been made in realizing laser-driven accelerators that are cheap and very compact compared with conventional rf-accelerators. Proton and ion beams have been produced with particle energies of up to 50 MeV and several MeV/u, respectively, with outstanding properties in terms of transverse emittance and current. These beams typically exhibit an exponentially decaying energy distribution, but almost all advanced applications, such as oncology, proton imaging or fast ignition, require quasimonoenergetic beams with a low energy spread. The majority of the experiments investigated ion acceleration in the target normal sheath acceleration (TNSA) regime with comparably thick targets in the μm range. In this thesis ion acceleration is investigated from nm-scaled targets, which are partially produced at the University of Munich with thickness as low as 3 nm. Experiments have been carried out at LANL's Trident high-power and high-contrast laser (80 J, 500 fs, λ=1054 nm), where ion acceleration with these nano-targets occurs during the relativistic transparency of the target, in the so-called Breakout afterburner (BOA) regime. With a novel high resolution and high dispersion Thomson parabola and ion wide angle spectrometer, thickness dependencies of the ions angular distribution, particle number, average and maximum energy have been measured. Carbon C6+ energies reached 650 MeV and 1 GeV for unheated and heated targets, respectively, and proton energies peaked at 75 MeV and 120 MeV for diamond and CH2 targets. Experimental data is presented, where the conversion efficiency into carbon C6+ (protons) is investigated and found to have an up to 10fold (5fold) increase over the TNSA regime. With circularly polarized laser light, quasi-monoenergetic carbon ions have been generated from the same nm-scaled foil targets at Trident with an

  4. Way to increase the user access at the LCLS baseline

    International Nuclear Information System (INIS)

    Although the LCLS photon beam is meant for a single user, the baseline undulator is long enough to serve two users simultaneously. To this end, we propose a setup composed of two simple elements: an X-ray mirror pair for X-ray beam deflection, and a short (4 m-long) magnetic chicane, which creates an offset for mirror pair installation in the middle of the baseline undulator. The insertable mirror pair can be used for spatial separation of the X-ray beams generated in the first and in the second half of the baseline undulator. The method of deactivating one half and activating another half of the undulator is based on the rapid switching of the FEL amplification process. As proposed elsewhere, using a kicker installed upstream of the LCLS baseline undulator and an already existing corrector in the first half of the undulator, it is possible to rapidly switch the X-ray beam from one user to another, thus providing two active beamlines at any time. We present simulation results dealing with the LCLS baseline, and show that it is possible to generate two saturated SASE X-ray beams in the whole 0.8-8 keV photon energy range in the same baseline undulator. These can be exploited to serve two users. Implementation of the proposed technique does not perturb the baseline mode of operation of the LCLS undulator. Moreover, the magnetic chicane setup is very flexible, and can be used as a self-seeding setup too. We present simulation results for the LCLS baseline undulator with SHAB (second harmonic afterburner) and show that one can produce monochromatic radiation at the 2nd harmonic as well as at the 1st. We describe an efficient way for obtaining multi-user operation at the LCLS hard X-ray FEL. To this end, a photon beam distribution system based on the use of crystals in the Bragg reflection geometry is proposed. The reflectivity of crystal deflectors can be switched fast enough by flipping the crystals with piezoelectric devices similar to those for X-ray phase retarders

  5. Ion acceleration from relativistic laser nano-target

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Daniel

    2012-01-06

    Laser-ion acceleration has been of particular interest over the last decade for fundamental as well as applied sciences. Remarkable progress has been made in realizing laser-driven accelerators that are cheap and very compact compared with conventional rf-accelerators. Proton and ion beams have been produced with particle energies of up to 50 MeV and several MeV/u, respectively, with outstanding properties in terms of transverse emittance and current. These beams typically exhibit an exponentially decaying energy distribution, but almost all advanced applications, such as oncology, proton imaging or fast ignition, require quasimonoenergetic beams with a low energy spread. The majority of the experiments investigated ion acceleration in the target normal sheath acceleration (TNSA) regime with comparably thick targets in the {mu}m range. In this thesis ion acceleration is investigated from nm-scaled targets, which are partially produced at the University of Munich with thickness as low as 3 nm. Experiments have been carried out at LANL's Trident high-power and high-contrast laser (80 J, 500 fs, {lambda}=1054 nm), where ion acceleration with these nano-targets occurs during the relativistic transparency of the target, in the so-called Breakout afterburner (BOA) regime. With a novel high resolution and high dispersion Thomson parabola and ion wide angle spectrometer, thickness dependencies of the ions angular distribution, particle number, average and maximum energy have been measured. Carbon C{sup 6+} energies reached 650 MeV and 1 GeV for unheated and heated targets, respectively, and proton energies peaked at 75 MeV and 120 MeV for diamond and CH{sub 2} targets. Experimental data is presented, where the conversion efficiency into carbon C{sup 6+} (protons) is investigated and found to have an up to 10fold (5fold) increase over the TNSA regime. With circularly polarized laser light, quasi-monoenergetic carbon ions have been generated from the same nm-scaled foil

  6. Dynamic modelling and characterisation of a solid oxide fuel cell integrated in a gas turbine cycle

    Energy Technology Data Exchange (ETDEWEB)

    Thorud, Bjoern

    2005-07-01

    This thesis focuses on three main areas within the field of SOFC/GT-technology: 1) Development of a dynamic SOFC/GT model. 2) Model calibration and sensitivity study. 3) Assessment of the dynamic properties of a SOFC/GT power plant. The SOFC/GT model developed in this thesis describes a pressurised tubular Siemens Westinghouse-type SOFC, which is integrated in a gas turbine cycle. The process further includes a plate-fin recuperator for stack air preheating, a prereformer, an anode exhaust gas recycling loop for steam/carbon-ratio control, an afterburner and a shell-tube heat exchanger for air preheating. The fuel cell tube, the recuperator and the shell-tube heat exchanger are spatially distributed models. The SOFC model is further thermally integrated with the prereformer. The compressor and turbine models are based on performance maps as a general representation of the characteristics. In addition, a shaft model which incorporates moment of inertia is included to account for gas turbine transients. The SOFC model is calibrated against experimentally obtained data from a single-cell experiment performed on a Siemens Westinghouse tubular SOFC. The agreement between the model and the experimental results is good. The sensitivity study revealed that the degree of prereforming is of great importance with respect to the axial temperature distribution of the fuel cell. Types of malfunctions are discussed prior to the dynamic behaviour study. The dynamic study of the SOFC/GT process is performed by simulating small and large load changes according to three different strategies; 1) Load change at constant mean fuel cell temperature. 2) Load change at constant turbine inlet temperature. 3) Load change at constant shaft speed. Of these three strategies, the constant mean fuel cell temperature strategy appears to be the most rapid load change method. Furthermore, this strategy implies the lowest degree of thermal cycling, the smoothest fuel cell temperature distribution and

  7. Clinical study of stability of micro implant used as orthodontic anchorage%正畸微型种植体的临床应用研究

    Institute of Scientific and Technical Information of China (English)

    招惠珍; 殷慧; 黄纪美

    2012-01-01

    目的 微型种植体承受正畸力后的稳定性研究.方法 回顾2008年3月至2011年3月在佛山市禅城区中心医院口腔科确诊的安氏Ⅱ类错颌畸形患者26例,在上颌第二前磨牙与第一磨前牙之间的牙槽骨上植入微型种植体,用以支抗内收的上前牙.并于植入种植体后2周、6个月时摄X线头颅定位侧位片,比较加力前后变化,测量微型种植体的移位情况.结果 6个月后水平位移约为0.5mm,垂直位移平均约为0.4mm,与植入时相比具有统计学意义(P<0.05),其中微型种植体伸长者7例,占26.9%.结论 微型种植体是一种相对稳定的支抗,在承受正畸力后,会出现位置移动以及自体伸长,所以在微型种植体植入时要注意避开血管、神经丰富的区域,植入后要定期复诊.%Objective To study the stability of micro implant anchorage after orthodontic force. Methods Totally 26 patients with micro implants as the maxillary anchorage from March 2008 to March 2011 to in our hospital were included in this study. Micro implants were inserted on the maxillary alveolar between the second premolar and the first molar as a direct anchorage for anterior teeth retraction. And at 2 weeks after implant placement, 6 months, X ray skull lateral positioning, comparing changes before and after the afterburner, measuring micro - implant shifting. Results After 6 months the horizontal displacement of approximately 0. 5 mm, the average vertical displacement of approximately 0. 4mm, with statistically significant when compared to implants (P < 0. 05 ) , which mini - implant elongation in 7 cases, 26.9%. Conclusions Micro implants is a relatively stable anchorage to withstand orthodontic force, the position will be mobile and self - body stretch, so the mini - implant should pay attention to avoid the blood vessels, nerve - rich are-a, regular follow - up after implantation.

  8. Studies of Fission Fragment Rocket Engine Propelled Spacecraft

    Science.gov (United States)

    Werka, Robert O.; Clark, Rodney; Sheldon, Rob; Percy, Thomas K.

    2014-01-01

    The NASA Office of Chief Technologist has funded from FY11 through FY14 successive studies of the physics, design, and spacecraft integration of a Fission Fragment Rocket Engine (FFRE) that directly converts the momentum of fission fragments continuously into spacecraft momentum at a theoretical specific impulse above one million seconds. While others have promised future propulsion advances if only you have the patience, the FFRE requires no waiting, no advances in physics and no advances in manufacturing processes. Such an engine unequivocally can create a new era of space exploration that can change spacecraft operation. The NIAC (NASA Institute for Advanced Concepts) Program Phase 1 study of FY11 first investigated how the revolutionary FFRE technology could be integrated into an advanced spacecraft. The FFRE combines existent technologies of low density fissioning dust trapped electrostatically and high field strength superconducting magnets for beam management. By organizing the nuclear core material to permit sufficient mean free path for escape of the fission fragments and by collimating the beam, this study showed the FFRE could convert nuclear power to thrust directly and efficiently at a delivered specific impulse of 527,000 seconds. The FY13 study showed that, without increasing the reactor power, adding a neutral gas to the fission fragment beam significantly increased the FFRE thrust through in a manner analogous to a jet engine afterburner. This frictional interaction of gas and beam resulted in an engine that continuously produced 1000 pound force of thrust at a delivered impulse of 32,000 seconds, thereby reducing the currently studied DRM 5 round trip mission to Mars from 3 years to 260 days. By decreasing the gas addition, this same engine can be tailored for much lower thrust at much higher impulse to match missions to more distant destinations. These studies created host spacecraft concepts configured for manned round trip journeys. While the

  9. DRAGON: Monte Carlo generator of particle production from a fragmented fireball in ultrarelativistic nuclear collisions

    Science.gov (United States)

    Tomášik, Boris

    2009-09-01

    A Monte Carlo generator of the final state of hadrons emitted from an ultrarelativistic nuclear collision is introduced. An important feature of the generator is a possible fragmentation of the fireball and emission of the hadrons from fragments. Phase space distribution of the fragments is based on the blast wave model extended to azimuthally non-symmetric fireballs. Parameters of the model can be tuned and this allows to generate final states from various kinds of fireballs. A facultative output in the OSCAR1999A format allows for a comprehensive analysis of phase-space distributions and/or use as an input for an afterburner. Program summaryProgram title: DRAGON Catalogue identifier: AEDK_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDK_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 6383 No. of bytes in distributed program, including test data, etc.: 32 756 Distribution format: tar.gz Programming language: C++ Computer: PC Pentium 4, though no particular tuning for this machine was performed Operating system: Linux; the program has been successfully run on Gentoo Linux 2.6, RedHat Linux 9, Debian Linux 4.0, all with g++ compiler. It also ran successfully on MS Windows under Microsoft Visual C++ 2008 Express Edition as well as under cygwin/g++ RAM: 100 Mbytes Supplementary material: Sample output files from the test run, provided in the distribution, are available. Classification: 11.2 Nature of problem: Deconfined matter produced in ultrarelativistic nuclear collisions expands and cools down and eventually returns into the confined phase. If the expansion is fast, the fireball could fragment either due to spinodal decomposition or due to suddenly arising bulk viscous force. Particle abundances are reasonably well described with just a few parameters

  10. Comparaison de la performance environnementale de la production thermique d'electricite avec et sans sequestration geologique du dioxyde de carbone

    Science.gov (United States)

    Bellerive, Nathalie

    The research project hypothesis is that CO2 capture and sequestration technologies (CSC) leads to a significant decrease in global warming, but increases the impact of all other aspects of the study. This is because other processes used for CO2 capture and sequestration require additional quantities of raw materials and energy. Two other objectives are described in this project. The first is the modeling of an Integrated Gasification Combined Cycle power plant for which there is no known generic data. The second is to select the right hypothesis regarding electrical production technologies, CO2 capture, compression and transportation by pipeline and finally sequestration. "Life Cycle Assessment" (LCA) analyses were chosen for this research project. LCA is an exhaustive quantitative method used to evaluate potential environmental impacts associated with a product, a service or an activity from resource extraction to waste elimination. This tool is governed by ISO 14 040 through ISO 14 049 and is sustained by the Society of Environmental Toxicology and Chemistry (SETAC) and the United Nations Environment Program (UNEP). Two power plants were studied, the Integrated Gasification Combined Cycle (IGCC) power plant and the Natural Gas Combined Cycle (NGCC) power plant. In order to sequester CO2 in geological formation, it is necessary to extract CO2from emission flows. For the IGCC power plant, CO 2 was captured before the burning phase. For the NGCC power plant, the capture was done during the afterburning phase. Once the CO2 was isolated, it was compressed and directed through a transportation pipe 1 000 km in length on the ground surface and in the sea. It is hypothesized that the power plant is 300 km from the shore and the sequestration platform 700 km from France's shore, in the North Sea. The IGCC power plant modeling and data selection regarding CO2 capture and sequestration were done by using primary data from the industry and the Ecoinvent generic database

  11. Numerical Simulation of an Enclosed Laminar Jet Diffusion Flame in Microgravity Environment: Comparison with ELF Data

    Science.gov (United States)

    Jia, Kezhong; Venuturumilli, Rajasekhar; Ryan, Brandon J.; Chen, Lea-Der

    2001-01-01

    Enclosed diffusion flames are commonly found in practical combustion systems, such as the power-plant combustor, gas turbine combustor, and jet engine after-burner. In these systems, fuel is injected into a duct with a co-flowing or cross-flowing air stream. The diffusion flame is found at the surface where the fuel jet and oxygen meet, react, and consume each other. In combustors, this flame is anchored at the burner (i.e., fuel jet inlet) unless adverse conditions cause the flame to lift off or blow out. Investigations of burner stability study the lift off, reattachment, and blow out of the flame. Flame stability is strongly dependent on the fuel jet velocity. When the fuel jet velocity is sufficiently low, the diffusion flame anchors at the burner rim. When the fuel jet velocity is increased, the flame base gradually moves downstream. However, when the fuel jet velocity increases beyond a critical value, the flame base abruptly jumps downstream. When this "jump" occurs, the flame is said to have reached its lift-off condition and the critical fuel jet velocity is called the lift-off velocity. While lifted, the flame is not attached to the burner and it appears to float in mid-air. Flow conditions are such that the flame cannot be maintained at the burner rim despite the presence of both fuel and oxygen. When the fuel jet velocity is further increased, the flame will eventually extinguish at its blowout condition. In contrast, if the fuel jet velocity of a lifted flame is reduced, the flame base moves upstream and abruptly returns to anchor at the burner rim. The fuel jet velocity at reattachment can be much lower than that at lift off, illustrating the hysteresis effect present in flame stability. Although there have been numerous studies of flame stability, the controlling mechanisms are not well understood. This uncertainty is described by Pitts in his review of various competing theories of lift off and blow out in turbulent jet diffusion flames. There has

  12. A Collaborative Analysis Tool for Integrated Hypersonic Aerodynamics, Thermal Protection Systems, and RBCC Engine Performance for Single Stage to Orbit Vehicles

    Science.gov (United States)

    Stanley, Thomas Troy; Alexander, Reginald; Landrum, Brian

    2000-01-01

    the process may be repeated altering the trajectory or some other input to reduce the TPS mass. E-PSURBCC is an "engine performance" model and requires the specification of inlet air static temperature and pressure as well as Mach number (which it pulls from the HYFIM and POST trajectory files), and calculates the corresponding stagnation properties. The engine air flow path geometry includes inlet, a constant area section where the rocket is positioned, a subsonic diffuser, a constant area afterburner, and either a converging nozzle or a converging-diverging nozzle. The current capabilities of E-PSURBCC ejector and ramjet mode treatment indicated that various complex flow phenomena including multiple choking and internal shocks can occur for combinations of geometry/flow conditions. For a given input deck defining geometry/flow conditions, the program first goes through a series of checks to establish whether the input parameters are sound in terms of a solution path. If the vehicle/engine performance fails mission goals, the engineer is able to collaboratively alter the vehicle moldline to change aerodynamics, or trajectory, or some other input to achieve orbit. The problem described is an example of the need for collaborative design and analysis. RECIPE is a cross-platform application capable of hosting a number of engineers and designers across the Internet for distributed and collaborative engineering environments. Such integrated system design environments allow for collaborative team design analysis for performing individual or reduced team studies. To facilitate the larger number of potential runs that may need to be made, RECIPE connects the computer codes that calculate the trajectory data, aerodynamic data based on vehicle geometry, heat rate data, TPS masses, and vehicle and engine performance, so that the output from each tool is easily transferred to the model input files that need it.