Powered by Deep Web Technologies
Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Strategic Technology JET PROPULSION LABORATORY  

E-Print Network [OSTI]

Strategic Technology Directions JET PROPULSION LABORATORY National Aeronautics and Space Administration 2 0 0 9 #12;© 2009 California Institute of Technology. Government sponsorship acknowledged. #12;Strategic Technology Directions 2009 offers a distillation of technologies, their links to space missions

Waliser, Duane E.

2

An investigation of the entrainment effects of a propulsive jet on the base pressure of blunt based bodies  

E-Print Network [OSTI]

and Henderson did a parameter correlation of data on 6 the effect of the supersonic power on base drag, using some obser- vations of Cubbsge . This correlation dealt only with Phase 4. Three of the flow regime, and it resulted in a formula wh1ch pre- dicted... coefficient of a body with th1s base geometry, one must first determine the base pres- sure coefficient with no propulsive jet and then add. the delta base pressure coefficient interpolated from the cucves. Both the Brazzel and Henderson and Mc...

Berry, Ronald Allen

1973-01-01T23:59:59.000Z

3

Vortex Rings in Bio-inspired and Biological Jet Propulsion Paul S. Krueger1, a  

E-Print Network [OSTI]

, J. Tyler Nichols1,c , Ian K. Bartol2,d , and William J. Stewart2,e 1 Department of Mechanical of the pulse is ejected as a trailing jet. Recent results from mechanical pulsed- jets have demonstrated that vortex rings lead to thrust augmentation through the acceleration of additional ambient fluid

Hynes, Wayne L.

4

JET PROPULSION LABORATORY COVER: FROM  

E-Print Network [OSTI]

"G UVER 155 Bl;JLDI:-JGS. 1:-1 THIS PA:-IORAMIC VIEW, THE SA=-- GAB- IUEL ,\\I011NTr\\J:-I~ I'Ot{.\\1 A Mi in the robotic explnration ofthe solarsystem:As a NASA Jteld center, JPL is charged with responsibilityfor a l7lVad range ofmajor robotic planetary missions and space science instruments. .. The advancement ofscientific

Waliser, Duane E.

5

E-Print Network 3.0 - advanced space propulsion Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: for space drilling. The Jet Propulsion Laboratory's (JPL) ultrasonicsonic drillercorer (USDC... 1 Design and Modeling of the NU Smart Space Drilling System (SSDS)...

6

Antonio Diaz-Calderon Jet Propulsion Laboratory  

E-Print Network [OSTI]

@jpl.nasa.gov Alonzo Kelly The Robotics Institute Carnegie Mellon University On-Line Stability Margin and Attitude which move heavy loads, accelerate or brake aggressively, turn at speed, or operate on sloped terrain

Kelly, Alonzo

7

7PUBLIC INFORMATION OFFICE JET PROPULSION LABORATORY  

E-Print Network [OSTI]

, as a result of efforts by the joint NASA-ESA mission operations team and NASA's Deep Space Network. Although degrees, scientists on the joint NASA-European Space Agency (ESA) mission reported. "Ulysses is gathering important new information about the sun and its environment as it continues to journey farther south toward

Christian, Eric

8

PUBLIC INFORMATION OFFICE JET PROPULSION LABORATORY  

E-Print Network [OSTI]

, velocity and turbulence of the solar atmosphere. Dr. Michael Bird of the University of Bonn, Germany from Ulysses will pass close to the sun's surface and travel through the dense lower solar atmosphere," Page said. At closest approach, the signals will cross through 1 #12;the sun's corona at four solar

Christian, Eric

9

Advanced Propulsion Technology Strategy  

Broader source: Energy.gov (indexed) [DOE]

Alternative Sources) Hydrogen Time ADVANCED PROPULSION TECHNOLOGY STRATEGY DOWNSIZED TURBO GAS ENGINE CHEVROLET CRUZE 1.4L TURBO ECOTEC Downsized SIDI Turbo Boosting HCCI -...

10

M. Bahrami ENSC 461 (S 11) Jet Propulsion Cycle 1 Ideal JetPropulsion Cycle  

E-Print Network [OSTI]

for fuel economy and speed high speed exhaust gases are mixed with the lower speed air in the by-pas where the turbine work is just equal to the compressor work plus some auxiliary power for pumps-4: constant pressure heat addition 4-5: isentropic expansion through the turbine during which work

Bahrami, Majid

11

Progress in colloid propulsion  

E-Print Network [OSTI]

In the early decades of the Space Age, a great deal of work was put into the development of the Colloid Thruster as an electric propulsion system for spacecraft. In spite of the effort by the end of the 70s the programs ...

López Urdiales, Jóse Mariano, 1977-

2004-01-01T23:59:59.000Z

12

Propulsion engineering study for small-scale Mars missions  

SciTech Connect (OSTI)

Rocket propulsion options for small-scale Mars missions are presented and compared, particularly for the terminal landing maneuver and for sample return. Mars landing has a low propulsive {Delta}v requirement on a {approximately}1-minute time scale, but at a high acceleration. High thrust/weight liquid rocket technologies, or advanced pulse-capable solids, developed during the past decade for missile defense, are therefore more appropriate for small Mars landers than are conventional space propulsion technologies. The advanced liquid systems are characterize by compact lightweight thrusters having high chamber pressures and short lifetimes. Blowdown or regulated pressure-fed operation can satisfy the Mars landing requirement, but hardware mass can be reduced by using pumps. Aggressive terminal landing propulsion designs can enable post-landing hop maneuvers for some surface mobility. The Mars sample return mission requires a small high performance launcher having either solid motors or miniature pump-fed engines. Terminal propulsion for 100 kg Mars landers is within the realm of flight-proven thruster designs, but custom tankage is desirable. Landers on a 10 kg scale also are feasible, using technology that has been demonstrated but not previously flown in space. The number of sources and the selection of components are extremely limited on this smallest scale, so some customized hardware is required. A key characteristic of kilogram-scale propulsion is that gas jets are much lighter than liquid thrusters for reaction control. The mass and volume of tanks for inert gas can be eliminated by systems which generate gas as needed from a liquid or a solid, but these have virtually no space flight history. Mars return propulsion is a major engineering challenge; earth launch is the only previously-solved propulsion problem requiring similar or greater performance.

Whitehead, J.

1995-09-12T23:59:59.000Z

13

Hypersonic missile propulsion system  

SciTech Connect (OSTI)

Pratt and Whitney is developing the technology for hypersonic components and engines. A supersonic combustion ramjet (scramjet) database was developed using hydrogen fueled propulsion systems for space access vehicles and serves as a point of departure for the current development of hydrocarbon scramjets. The Air Force Hypersonic Technology (HyTech) Program has put programs in place to develop the technologies necessary to demonstrate the operability, performance and structural durability of an expendable, liquid hydrocarbon fueled scramjet system that operates from Mach 4 to 8. This program will culminate in a flight type engine test at representative flight conditions. The hypersonic technology base that will be developed and demonstrated under HyTech will establish the foundation to enable hypersonic propulsion systems for a broad range of air vehicle applications from missiles to space access vehicles. A hypersonic missile flight demonstration is planned in the DARPA Affordable Rapid Response Missile Demonstrator (ARRMD) program in 2001.

Kazmar, R.R.

1998-11-01T23:59:59.000Z

14

Lightweighting and Propulsion Materials Roadmapping Workshop...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Lightweighting and Propulsion Materials Roadmapping Workshop Outbrief Lightweighting and Propulsion Materials Roadmapping Workshop Outbrief 2012 DOE Hydrogen and Fuel Cells Program...

15

Life Cycle Modeling of Propulsion Materials  

Broader source: Energy.gov (indexed) [DOE]

propulsion materials manufacturing technologies with an emphasis on aluminum, magnesium, titanium, and ceramics * Advanced propulsion materials' potential in heavy-duty...

16

Lagrangian simulation of transverse jets with a distribution-based diffusion scheme  

E-Print Network [OSTI]

Transverse jets form a dominant group of flow fields arising in many applications of modern energy utilization, including propulsion and effluent dispersion. Furthermore, they form canonical examples where the flow field ...

Wee, Daehyun, 1974-

2007-01-01T23:59:59.000Z

17

Vorticity structure and evolution in a transverse jet with new algorithms for scalable particle simulation  

E-Print Network [OSTI]

Transverse jets arise in many applications, including propulsion, effluent dispersion, oil field flows, V/STOL aerodynamics, and drug delivery. Furthermore, they exemplify flows dominated by coherent structures that cascade ...

Marzouk, Youssef M. (Youssef Mohamed)

2004-01-01T23:59:59.000Z

18

Nuclear Propulsion in Space (1968)  

SciTech Connect (OSTI)

Project NERVA was an acronym for Nuclear Engine for Rocket Vehicle Application, a joint program of the U.S. Atomic Energy Commission and NASA managed by the Space Nuclear Propulsion Office (SNPO) at the Nuclear Rocket Development Station in Jackass Flats, Nevada U.S.A. Between 1959 and 1972, the Space Nuclear Propulsion Office oversaw 23 reactor tests, both the program and the office ended at the end of 1972.

None

2012-06-23T23:59:59.000Z

19

Nuclear Propulsion in Space (1968)  

ScienceCinema (OSTI)

Project NERVA was an acronym for Nuclear Engine for Rocket Vehicle Application, a joint program of the U.S. Atomic Energy Commission and NASA managed by the Space Nuclear Propulsion Office (SNPO) at the Nuclear Rocket Development Station in Jackass Flats, Nevada U.S.A. Between 1959 and 1972, the Space Nuclear Propulsion Office oversaw 23 reactor tests, both the program and the office ended at the end of 1972.

None

2014-06-17T23:59:59.000Z

20

Astrophysical Jets  

SciTech Connect (OSTI)

Many astrophysical sources - especially those powered by release of gravitational energy - are associated with an outflow of material, generally taking place along the axis of symmetry of the system. In the most extreme cases, the outflow is accelerated to relativistic speeds; such a phenomenon is known as an astrophysical jet. When a relativistic jet points close to our line of sight, the observed radiation is strongly Doppler-boosted. Most spectacular cases of astrophysical jets are those produced by active galactic nuclei, where the measured spectrum - presumably dominated by the radiation from the jet - reaches up to the multi-GeV range. Our knowledge of these jets is limited: we don't fully understand how are they formed, collimated, and accelerated, and what is the process of conversion of the bulk energy of the jet into radiation. We anticipate that the increased sensitivity of GLAST will provide us with spectacular data yielding new insights as to their origin and structure.

Madejski, Grzegorz (SLAC) [SLAC

2006-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Jet Propulsion Laboratory 1972-1973 Annual Report  

E-Print Network [OSTI]

flyby, solar-electric powered space- craft to Comet Encke in the 1980s. In an effort to effect, and two Mariner-class vehicles for 1977 launch to Jupiter and Saturn. Although the Laboratory has experi

Waliser, Duane E.

22

SUNITA PAYRA VERMA Jet Propulsion Laboratory, California Institute of Technology  

E-Print Network [OSTI]

Associate · In project entitled "Scale up to obtain super clean coal - Organo-refining and identification

23

NASA's Jet Propulsion Laboratory Pasadena, California 91109-8099  

E-Print Network [OSTI]

Government nor any person acting on behalf of the United States Government assumes any liability resulting privately owned rights. If trade names or manufacturers' names are used in this report by utilizing the transient response of a current pulse. The performance of such a device, using (Bi,Sb)2Te3

Chen, Gang

24

Stellar jets  

E-Print Network [OSTI]

With a goal of understanding the conditions under which jets might be produced in novae and related objects, I consider the conditions under which jets are produced from other classes of accreting compact objects. I give an overview of accretion disk spectral states, including a discussion of in which states these jets are seen. I highlight the differences between neutron stars and black holes, which may help give us insights about when and how the presence of a solid surface may help or inhibit jet production.

Thomas J. Maccarone

2008-05-23T23:59:59.000Z

25

PROPULSION AND ENERGY Terrestrial energy  

E-Print Network [OSTI]

PROPULSION AND ENERGY Terrestrial energy On the morning of Monday, August 29, Hurri- cane Katrina dependence we all have on power and energy systems. Nine major oil re- fineries in Louisiana and Mississippi- trial energy community is the question of why alternative energy sources, such as coal, solar, wind

Aggarwal, Suresh K.

26

Emerging Jets  

E-Print Network [OSTI]

In this work, we propose a novel search strategy for new physics at the LHC that utilizes calorimeter jets that (i) are composed dominantly of displaced tracks and (ii) have many different vertices within the jet cone. Such emerging jet signatures are smoking guns for models with a composite dark sector where a parton shower in the dark sector is followed by displaced decays of dark pions back to SM jets. No current LHC searches are sensitive to this type of phenomenology. We perform a detailed simulation for a benchmark signal with two regular and two emerging jets, and present and implement strategies to suppress QCD backgrounds by up to six orders of magnitude. At the 14 TeV LHC, this signature can be probed with mediator masses as large as 1.5 TeV for a range of dark pion lifetimes, and the reach is increased further at the high-luminosity LHC. The emerging jet search is also sensitive to a broad class of long-lived phenomena, and we show this for a supersymmetric model with R-parity violation. Possibilities for discovery at LHCb are also discussed.

Pedro Schwaller; Daniel Stolarski; Andreas Weiler

2015-02-24T23:59:59.000Z

27

Emerging Jets  

E-Print Network [OSTI]

In this work, we propose a novel search strategy for new physics at the LHC that utilizes calorimeter jets that (i) are composed dominantly of displaced tracks and (ii) have many different vertices within the jet cone. Such emerging jet signatures are smoking guns for models with a composite dark sector where a parton shower in the dark sector is followed by displaced decays of dark pions back to SM jets. No current LHC searches are sensitive to this type of phenomenology. We perform a detailed simulation for a benchmark signal with two regular and two emerging jets, and present and implement strategies to suppress QCD backgrounds by up to six orders of magnitude. At the 14 TeV LHC, this signature can be probed with mediator masses as large as 1.5 TeV for a range of dark pion lifetimes, and the reach is increased further at the high-luminosity LHC. The emerging jet search is also sensitive to a broad class of long-lived phenomena, and we show this for a supersymmetric model with R-parity violation. Possibilit...

Schwaller, Pedro; Weiler, Andreas

2015-01-01T23:59:59.000Z

28

Pure Nuclear Fusion Bomb Propulsion  

E-Print Network [OSTI]

Recent progress towards the non-fission ignition of thermonuclear micro-explosions raises the prospect for a revival of the nuclear bomb propulsion idea, both for the fast transport of large payloads within the solar system and the launch into earth orbit without the release of fission products into the atmosphere. To reach this goal three areas of research are of importance: 1)Compact thermonuclear ignition drivers. 2)Fast ignition and deuterium burn. 3)Space-craft architecture involving magnetic insulation and GeV electrostatic potentials

Winterberg, F

2008-01-01T23:59:59.000Z

29

SciTech Connect: Hydrogen peroxide propulsion for smaller satellites...  

Office of Scientific and Technical Information (OSTI)

Conference: Hydrogen peroxide propulsion for smaller satellites (SSC98-VIII-1) Citation Details In-Document Search Title: Hydrogen peroxide propulsion for smaller satellites...

30

Vehicle Technologies Office: 2010 Propulsion Materials R&D Annual...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

0 Propulsion Materials R&D Annual Progress Report Vehicle Technologies Office: 2010 Propulsion Materials R&D Annual Progress Report 2010 annual progress report focusing on enabling...

31

Vehicle Technologies Office: 2008 Propulsion Materials R&D Annual...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

8 Propulsion Materials R&D Annual Progress Report Vehicle Technologies Office: 2008 Propulsion Materials R&D Annual Progress Report 2008propulsionmaterials.pdf More Documents &...

32

Vehicle Technologies Office: 2011 Propulsion Materials R&D Annual...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Vehicle Technologies Office: 2011 Propulsion Materials R&D Annual Progress Report Vehicle Technologies Office: 2011 Propulsion Materials R&D Annual Progress Report 2011 annual...

33

Vehicle Technologies Office: 2012 Propulsion Materials R&D Annual...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

2012 Propulsion Materials R&D Annual Progress Report Vehicle Technologies Office: 2012 Propulsion Materials R&D Annual Progress Report 2012 annual progress report focusing on...

34

Vehicle Technologies Office: 2013 Propulsion Materials R&D Annual...  

Energy Savers [EERE]

3 Propulsion Materials R&D Annual Progress Report Vehicle Technologies Office: 2013 Propulsion Materials R&D Annual Progress Report This report describes the progress made during...

35

Enabling Green Energy and Propulsion Systems via Direct Noise...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

GE propulsion systems Enabling Green Energy and Propulsion Systems via Direct Noise Computation PI Name: Umesh Paliath PI Email: paliath@ge.com Institution: GE Global Research...

36

2008 Annual Merit Review Results Summary - 12. Propulsion Materials...  

Broader source: Energy.gov (indexed) [DOE]

2008 Annual Merit Review Results Summary - 12. Propulsion Materials 2008 Annual Merit Review Results Summary - 12. Propulsion Materials DOE Vehicle Technologies Annual Merit Review...

37

Vehicle Technologies Office: 2009 Propulsion Materials R&D Annual...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

9 Propulsion Materials R&D Annual Progress Report Vehicle Technologies Office: 2009 Propulsion Materials R&D Annual Progress Report 2009propulsionmaterials.pdf More Documents &...

38

Development of a Plasma Probe Positioner Positioner for Propulsion Research  

E-Print Network [OSTI]

(real-time, no delay) electric motor that divides a full rotation into a large number of steps1. #12 Advisor: Dr. Edgar Choueiri Mentor: Luke Uribarri #12;PPDyL 2 Outline Spacecraft Propulsion Electric vs. Chemical Propulsion How Electric Propulsion uses Plasma Problem with Electric Propulsion : Onset Solution

Petta, Jason

39

Integration of Electric Propulsion Systems with Spacecraft An Overview  

E-Print Network [OSTI]

electric propulsion systems are currently being developed ­ ranging from high-power (i.e., >10 kW) systems-propulsion systems to be used on small satellites? In the context of direct-drive electric propulsion? 1 Research1 Integration of Electric Propulsion Systems with Spacecraft ­ An Overview Thomas M. Liu1

Walker, Mitchell

40

Propulsion mechanisms in a helicon plasma thruster  

E-Print Network [OSTI]

Electric thrusters offer an attractive option for various in-space propulsion tasks due to their high thrust efficiencies. The performance characteristics of a compact electric thruster utilizing a helicon plasma source ...

Sinenian, Nareg

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Inclusive Jets in PHP  

E-Print Network [OSTI]

Differential inclusive-jet cross sections have been measured in photoproduction for boson virtualities Q^2 < 1 GeV^2 with the ZEUS detector at HERA using an integrated luminosity of 300 pb^-1. Jets were identified in the laboratory frame using the k_T, anti-k_T or SIScone jet algorithms. Cross sections are presented as functions of the jet pseudorapidity, eta(jet), and the jet transverse energy, E_T(jet). Next-to-leading-order QCD calculations give a good description of the measurements, except for jets with low E_T(jet) and high eta(jet). The cross sections have the potential to improve the determination of the PDFs in future QCD fits. Values of alpha_s(M_Z) have been extracted from the measurements based on different jet algorithms. In addition, the energy-scale dependence of the strong coupling was determined.

Roloff, Philipp

2013-01-01T23:59:59.000Z

42

Inclusive Jets in PHP  

E-Print Network [OSTI]

Differential inclusive-jet cross sections have been measured in photoproduction for boson virtualities Q^2 < 1 GeV^2 with the ZEUS detector at HERA using an integrated luminosity of 300 pb^-1. Jets were identified in the laboratory frame using the k_T, anti-k_T or SIScone jet algorithms. Cross sections are presented as functions of the jet pseudorapidity, eta(jet), and the jet transverse energy, E_T(jet). Next-to-leading-order QCD calculations give a good description of the measurements, except for jets with low E_T(jet) and high eta(jet). The cross sections have the potential to improve the determination of the PDFs in future QCD fits. Values of alpha_s(M_Z) have been extracted from the measurements based on different jet algorithms. In addition, the energy-scale dependence of the strong coupling was determined.

Philipp Roloff

2013-10-23T23:59:59.000Z

43

DC, AC and advanced EV propulsion systems  

SciTech Connect (OSTI)

Battery development and liquid fuel availability and cost are still the pacing factors in wide scale electric vehicle introduction. Propulsion systems also require technical development, however, if electric vehicles are to be acceptable in the marketplace in competition against ICE vehicles. Eaton Corporation has undertaken a program designed to identify and investigate three broad types of propulsion systems in identical test vehicles on the same test track under conditions as similar as possible. Characteristics of dc, ac and advanced systems are compared to date, and projections of anticipated results and further work are provided. The compelling advantages of multiple mechanical ratios in EV propulsion systems are reviewed. An emerging, but less obvious, advantage is higher overall system efficiency.

O'Neil, W.

1983-08-01T23:59:59.000Z

44

Power balance in a helicon plasma source for space propulsion  

E-Print Network [OSTI]

Electric propulsion systems provide an attractive option for various spacecraft propulsion applications due to their high specific impulse. The power balance of an electric thruster based on a helicon plasma source is ...

White, Daniel B., Jr

2008-01-01T23:59:59.000Z

45

MHD (magnetohydrodynamic) undersea propulsion: A novel concept with renewed interest  

SciTech Connect (OSTI)

This paper discusses the reasons for the national and international renewed interest in the concept of MHD seawater propulsion. The main advantages of this concept are presented, together with some of the technical challenges that need to be overcome to achieve reliability, performance, and stealth. The paper discusses in more detail some of the technical issues and loss mechanisms influencing the thruster performance in terms of its electrical efficiency. Among the issues discussed are the jet losses and nozzle efficiency. Ohmic losses and frictional losses inside the thruster. Also discussed are the electrical end losses caused by the fringing magnetic field near the end of the electrodes. It has been shown that the frictional and end losses can have strong adverse effects on the thruster performance. Furthermore, a parametric study has been performed to investigate the effects of several parameters on the performance of the MHD thrusters. Those parameters include the magnetic field, thruster diameter, all roughness, flow velocity, and electrical load factor. The results of the parametric study indicate that the thruster efficiency increases with the strength of the magnetic field and thruster diameter, and decreases with the wall roughness and the flow velocity. 8 refs., 8 figs.

Doss, E.D.; Geyer, H.K. (Argonne National Lab., IL (USA)); Roy, G.D. (Office of Naval Research, Arlington, VA (USA))

1990-01-01T23:59:59.000Z

46

Propulsion in a viscoelastic fluid Eric Laugaa  

E-Print Network [OSTI]

and a healthy respiratory system.8 Cilia are short flagella which produce fluid motion by means mechanisms and propulsion.9 In the upper respiratory tract, cilia are located in a thin layer of low influenced by viscoelastic stresses. Relevant examples include the ciliary transport of respiratory airway

Lauga, Eric

47

Jets at all scales  

E-Print Network [OSTI]

I discuss recent developments in the field of relativistic jets in AGNs. After a brief review of our current knowledge of emission from Blazars, I discuss some consequences of the recent detection made by {\\it Chandra} of X-ray emission from extended jets. Finally I report some recent results on the problem of the connection between accretion and jets, study that in principle could shed light on the important issue of jet formation.

F. Tavecchio

2002-12-11T23:59:59.000Z

48

Microquasars and Jets  

E-Print Network [OSTI]

I present an overview of past, present and future research on microquasars and jets, showing that microquasars, i.e. galactic jet sources, are among the best laboratories for high energy phenomena. After remindind the analogy with quasars, I focus on one of the best microquasar representatives, probably the archetype, namely GRS 1915+105, and present accretion and ejection phenomena, showing that only a multi-wavelength approach allows a better understanding of phenomena occuring in these sources. Thereafter, I review jets at different scales: compact jets, large-scale jets, and the interactions between ejections and the surrounding medium. I finish by speaking about microblazars and ultraluminous X-ray sources.

Sylvain Chaty

2005-06-01T23:59:59.000Z

49

SERAPHIM: A propulsion technology for fast trains  

SciTech Connect (OSTI)

The Segmented Rail Phased Induction Motor (SERAPHIM) is a compact, pulsed linear induction motor (LIM) offering a unique capability for very high speed train propulsion. It uses technology developed for the Sandia coilgun, an electromagnetic launcher designed to accelerate projectiles to several kilometers per second. Both aluminum cylinders and plates were accelerated to a kilometer per second (Mach 3) by passing through a sequence of coils which were energized at the appropriate time. Although this technology was developed for ultra-high velocity, it can be readily adapted to train propulsion for which, at sea level, the power required to overcome air resistance limits the operational speed to a more modest 300 mph. Here, the geometry is reversed. The coils are on the vehicle and the ``projectiles`` are fixed along the roadbed. SERAPHIM operates not by embedding flux in a conductor, but by excluding it. In this propulsion scheme, pairs of closely spaced coils on the vehicle straddle a segmented aluminum reaction rail. A high frequency current is switched on as a coil pair crosses an edge and remains off as they overtake the next segment. This induces surface currents which repel the coil. In essence, the pulsed coils push off segment edges because at the high frequency of operation, the flux has insufficient time to penetrate. In contrast to conventional LIMs, the performance actually improves with velocity, even for a minimal motor consisting of a single coil pair reacting with a single plate. This paper will present results of proof-of-principle tests, electromagnetic computer simulations, and systems analysis. It is concluded that this new linear induction motor can be implemented using existing technology and is a promising alternative propulsion method for very high speed rail transportation.

Kelly, B.; Turman, B.; Marder, B.; Rohwein, G.; Aeschliman, D.; Cowan, B.

1995-06-01T23:59:59.000Z

50

Simplest AB-Thermonuclear Space Propulsion and Electric Generator  

E-Print Network [OSTI]

The author applies, develops and researches mini-sized Micro- AB Thermonuclear Reactors for space propulsion and space power systems. These small engines directly convert the high speed charged particles produced in the thermonuclear reactor into vehicle thrust or vehicle electricity with maximum efficiency. The simplest AB-thermonuclear propulsion offered allows spaceships to reach speeds of 20,000 50,000 km/s (1/6 of light speed) for fuel ratio 0.1 and produces a huge amount of useful electric energy. Offered propulsion system permits flight to any planet of our Solar system in short time and to the nearest non-Sun stars by E-being or intellectual robots during a single human life period. Key words: AB-propulsion, thermonuclear propulsion, space propulsion, thermonuclear power system.

Alexander Bolonkin

2007-01-19T23:59:59.000Z

51

aircraft nuclear propulsion: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

engine technologies mature. Significant (more) Kirner, Rudi 2013-01-01 3 Pure Nuclear Fusion Bomb Propulsion CERN Preprints Summary: Recent progress towards the non-fission...

52

automotive propulsion system: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

analysis; automotive control system. I. INTRODUCTION In reliability Zachmann, Gabriel 49 Mini-Micro Thrusters, LOX Hydrocarbon Propulsion, and Attitude Control...

53

automotive propulsion systems: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

analysis; automotive control system. I. INTRODUCTION In reliability Zachmann, Gabriel 49 Mini-Micro Thrusters, LOX Hydrocarbon Propulsion, and Attitude Control...

54

advanced propulsion systems: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

for the tail's motion. Index terms--Fish propulsion, underwater robot, fish design. I. INTRODUCTION LTHOUGH almost all marine vehicles use propellers Papadopoulos,...

55

aircraft propulsion reactors: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

to produce adequate thrust, reduce ... Dicara, Daniel L 2006-01-01 13 Simplest AB-Thermonuclear Space Propulsion and Electric Generator CERN Preprints Summary: The author...

56

Enabling Green Energy and Propulsion Systems via Direct Noise...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Umesh Paliath, GE Global Research; Joe Insley, Argonne National Laboratory Enabling Green Energy and Propulsion Systems via Direct Noise Computation PI Name: Umesh Paliath PI...

57

Hotspots, Jets and Environments  

E-Print Network [OSTI]

I discuss the nature of `hotspots' and `jet knots' in the kpc-scale structures of powerful radio galaxies and their relationship to jet-environment interactions. I describe evidence for interaction between the jets of FRI sources and their local environments, and discuss its relationship to particle acceleration, but the main focus of the paper is the hotspots of FRIIs and on new observational evidence on the nature of the particle acceleration associated with them.

M. J. Hardcastle

2007-07-12T23:59:59.000Z

58

The Gasdynamic Mirror Fusion Propulsion System -- Revisited  

SciTech Connect (OSTI)

Many of the previous studies assessing the capability of the gasdynamic mirror (GDM) fusion propulsion system employed analyses that ignored the 'ambipolar' potential. This electrostatic potential arises as a result of the rapid escape of the electrons due to their small mass. As they escape, they leave behind an excess positive charge which manifests itself in an electric field that slows down the electrons while speeding up the ions until their respective axial diffusions are equalized. The indirect effect on the ions is that their confinement time is reduced relative to that of zero potential, and hence the plasma length must be increased to accommodate that change. But as they emerge from the thruster mirror - which serves as a magnetic nozzle - the ions acquire an added energy equal to that of the potential energy, and that in turn manifests itself in increased specific impulse and thrust. We assess the propulsive performance of the GDM thruster, based on the more rigorous theory, by applying it to a round trip Mars mission employing a continuous burn acceleration/deceleration type of trajectory. We find that the length of the device and travel time decrease with increasing plasma density, while the total vehicle mass reaches a minimum at a plasma density of 3 x 1016 cm-3. At such a density, and an initial DT ion temperature of 10 keV, a travel time of 60 days is found to be achievable at GDM propulsion parameters of about 200,000 seconds of specific impulse and approximately 47 kN of thrust.

Kammash, Terry [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, 2355 Bonisteel Blvd, Ann Arbor, MI 48109 (United States); Tang, Ricky [Department of Aerospace Engineering, University Michigan, 1320 Beal Ave, Ann Arbor, MI 48109 (United States)

2005-02-06T23:59:59.000Z

59

CMC intake ramp for hypersonic propulsion systems  

SciTech Connect (OSTI)

An alternative technology to produce CMC structural components with lower costs and shorter manufacturing times has been developed at the DLR. The process is based on liquid silicon infiltration (LSI) into porous carbon/carbon resulting in a C/C-SiC material whereby the load carrying fibres are internally protected against oxidation by SiC. The material`s adequate strength levels and the high reproducibility of the state-of-the-art process now allows the realization of CMC components. Representing a very complex structure of high integrity, an intake ramp for a hypersonic propulsion system has been designed, manufactured and tested, which is described in this paper.

Kochendoerfer, R.; Krenkel, W. [Institute of Structures and Design, Stuttgart, (Germany)

1995-12-01T23:59:59.000Z

60

Fusion Propulsion and Power for Future Flight  

SciTech Connect (OSTI)

There are innovative magnetic and electric confinement fusion power and propulsion system designs with potential for: vacuum specific impulses of 1500-2000 seconds with rocket engine thrust/mass ratios of 5-10 g`s; environmentally favorable exhaust emissions if aneutronic fusion propellants can be used; a 2 to 3-fold reduction in the mass of hypersonic airliners and SSTO aerospace planes; a 10 to 20 fold reduction in Mars expedition mass and cost (if propellant from planetary atmospheres is used); and feasibility or in-feasibility of these systems could be confirmed with a modest applied research and exploratory development cost.

Froning, H.D. Jr.

1996-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Nuclear propulsion system options for Mars missions  

SciTech Connect (OSTI)

This paper focuses on the use of a nuclear thermal rocket to accomplish a variety of space missions with emphasis on the manned Mars mission. The particle-bed-reactor type nuclear engine was chosen as the baseline engine because of its perceived versatility over other nuclear propulsion systems in conducting a wide variety of tasks. This study indicates that the particle-bed-reactor engine with its high engine thrust-to-weight ratio (about 20) and high specific impulse (about 950 to 1050 sec) offers distinct advantages over the larger and heavier NERVA-type nuclear engines.

Emrich, W.J. Jr.; Young, A.C. (NASA, Marshall Space Flight Center, Huntsville, AL (United States))

1992-03-01T23:59:59.000Z

62

Ultrahigh Specific Impulse Nuclear Thermal Propulsion  

SciTech Connect (OSTI)

Research on nuclear thermal propulsion systems (NTP) have been in forefront of the space nuclear power and propulsion due to their design simplicity and their promise for providing very high thrust at reasonably high specific impulse. During NERVA-ROVER program in late 1950's till early 1970's, the United States developed and ground tested about 18 NTP systems without ever deploying them into space. The NERVA-ROVER program included development and testing of NTP systems with very high thrust (~250,000 lbf) and relatively high specific impulse (~850 s). High thrust to weight ratio in NTP systems is an indicator of high acceleration that could be achieved with these systems. The specific impulse in the lowest mass propellant, hydrogen, is a function of square root of absolute temperature in the NTP thrust chamber. Therefor optimizing design performance of NTP systems would require achieving the highest possible hydrogen temperature at reasonably high thrust to weight ratio. High hydrogen exit temperature produces high specific impulse that is a diret measure of propellant usage efficiency.

Anne Charmeau; Brandon Cunningham; Samim Anghaie

2009-02-09T23:59:59.000Z

63

Interplanetary missions with the GDM propulsion system  

SciTech Connect (OSTI)

The Gasdynamic Mirror (GDM) fusion propulsion system utilizes a magnetic mirror machine in which a hot dense plasma is confined long enough to produce fusion energy while allowing a fraction of its charged particle population to escape from one end to generate thrust. The particles escaping through the opposite end have their energy converted to electric power which can be used to sustain the system in a steady state operation. With the aid of a power flow diagram the minimum demands on energy production can be established and the propulsive capability of the system can be determined by solving an appropriate set of governing equations. We apply these results to several missions within the solar system and compute the trip time by invoking a continuous burn, acceleration/deceleration type of trajectory with constant thrust and specific impulse. Ignoring gravitational effects of the planets or the sun, and neglecting the change in the Earth's position during the flight we compute the round trip time for missions from Earth to Mars, Jupiter, and Pluto using linear distances and certain payload fractions. We find that a round trip to Mars with the GDM rocket takes about 170 days while those to Jupiter and Pluto take 494 and 1566 days respectively.

Kammash, T.; Emrich, W. Jr. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Marshall Space Flight Center, Huntsville, Alabama 35812 (United States)

1998-01-15T23:59:59.000Z

64

ab-ramjet space propulsion: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

12 NASA Procedural Requirements NRPTA National Rocket Propulsion Testing Alliance OIG Office of Inspector General RPT Rocket Propulsion Test SLS Space Launch System...

65

E-Print Network 3.0 - accent propulsion lander Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

vehicle design and operations, propulsion, orbital mechanics, spacecraft... on hypersonic flight and electric rocket propulsion. Dr. Erwin teaches two lower-division...

66

J_{E_T}: A Global Jet Finding Algorithm  

E-Print Network [OSTI]

We introduce a new jet-finding algorithm for a hadron collider based on maximizing a J_{E_T} function for all possible combinations of particles in an event. This function prefers a larger value of the jet transverse energy and a smaller value of the jet mass. The jet shape is proved to be a circular cone in Cartesian coordinates with the geometric center shifted from the jet momentum toward the central region. The jet cone size shrinks for a more forward jet. We have implemented our J_{E_T} algorithm with a reasonable running time scaling as N n^3, where "N" is the total number of particles and "n" (much less than N) is the number of particles in a fiducial region. Many features of our J_{E_T} jets are similar to anti-k_t jets, including the reconstructed jet momentum and the "back-reaction" from soft contamination. Nevertheless, when the jet parameters in the two algorithms are matched using QCD jets, we find that the J_{E_T} algorithm has a larger efficiency than anti-k_t for identifying objects with hard splittings such as a W-jet.

Yang Bai; Zhenyu Han; Ran Lu

2014-11-13T23:59:59.000Z

67

Heatpipe space power and propulsion systems  

SciTech Connect (OSTI)

Safe, reliable, low-mass space power and propulsion systems could have numerous civilian and military applications. This paper discusses two fission-powered concepts: the Heatpipe Power System (HPS) that provides power only, and the Heatpipe Bimodal System (HBS) that provides both power and thermal propulsion. Both concepts have 10 important features. First, only existing technology and recently tested fuel forms are used. Second, fuel can be removed whenever desired, greatly facilitating system fabrication and handling. Third, full electrically heated system testing is possible, with minimal operations required to replace the heaters with fuel and ready the system for launch. Fourth, the systems are passively subcritical during launch accidents. Fifth, a modular approach is used, and most technical issues can be resolved with inexpensive module tests. Sixth, bonds between dissimilar metals are minimized. Seventh, there are no single point failures during power mode operation. Eighth, fuel burnup rate is quite low to help ensure greater than 10-year system life. Ninth, there are no pumped coolant loops, and the systems can be shut down and restarted without coolant freeze/thaw concerns. Finally, a full ground nuclear test is not needed, and development costs will be low. The baseline HPS uses SNAP-10A-style thermoelectric power converters to produce 5 kWe at a system mass of about 500 kg. The unicouple thermoelectric converters have a hot shoe temperature of 1275 K and reject waste heat at 775 K. This type of thermoelectric converter has been used extensively by the space program, demonstrating an operational lifetime of decades. At higher thermal power, the same core can produce over 10 kWe using thermoelectric converters, and over 50 kWe using advanced power conversion systems.

Houts, M.G.; Poston, D.I.; Ranken, W.A.

1995-07-01T23:59:59.000Z

68

Angular Scaling In Jets  

SciTech Connect (OSTI)

We introduce a jet shape observable defined for an ensemble of jets in terms of two-particle angular correlations and a resolution parameter R. This quantity is infrared and collinear safe and can be interpreted as a scaling exponent for the angular distribution of mass inside the jet. For small R it is close to the value 2 as a consequence of the approximately scale invariant QCD dynamics. For large R it is sensitive to non-perturbative effects. We describe the use of this correlation function for tests of QCD, for studying underlying event and pile-up effects, and for tuning Monte Carlo event generators.

Jankowiak, Martin; Larkoski, Andrew J.; /SLAC

2012-02-17T23:59:59.000Z

69

ATLAS Jet Energy Scale  

E-Print Network [OSTI]

Jets originating from the fragmentation of quarks and gluons are the most common, and complicated, final state objects produced at hadron colliders. A precise knowledge of their energy calibration is therefore of great importance at experiments at the Large Hadron Collider at CERN, while is very difficult to ascertain. We present in-situ techniques and results for the jet energy scale at ATLAS using recent collision data. ATLAS has demonstrated an understanding of the necessary jet energy corrections to within \\approx 4% in the central region of the calorimeter.

D. Schouten; A. Tanasijczuk; M. Vetterli; for the ATLAS Collaboration

2012-01-11T23:59:59.000Z

70

Form, function and flow in the plankton : jet propulsion and filtration by pelagic tunicates  

E-Print Network [OSTI]

Trade-offs between filtration rate and swimming performance among several salp species with distinct morphologies and swimming styles were compared. Small-scale particle encounter at the salp filtering apparatus was also ...

Sutherland, Kelly Rakow

2010-01-01T23:59:59.000Z

71

JET PROPULSION LABORATORY 1981 ANNUAL REPORT Qwer The tem:lln of the  

E-Print Network [OSTI]

Imagmg Radar-A (SIR-A), flown on NASA's space shuttle Columbia In Novembelr 1981 The marbled, swtrl- mg. Thus I feel that last fall we not only passed through the nadir point in terms of es- tablishing ]PL

Waliser, Duane E.

72

Jet Propulsion Laboratory 1974-1975 Annual Report Cover The Manner 10 commemoratMl  

E-Print Network [OSTI]

. The hydrogen injection engine project entered the vehicle system design phase. A study on alternative would enable this eHort to interface with the Mariner Jupiter/Saturn 1977 Project at minimum cost of a national geothermal energy program and development of low-cost silicon arrays in an eHort to improve

Waliser, Duane E.

73

JET PROPULSION LABORATORY 1987 ANNUAL REPORT (Cover) At the heart of the  

E-Print Network [OSTI]

-sufficient in energy, JPL responded with research and develop- ment in solar photovoltaics, solar thermal energy, and integrity as guiding principles; (2) as NASA's lead center for unmanned exploration of the solar system, JPL- ally funded research and development center, JPL helps the United States solve technologi- cal problems

Waliser, Duane E.

74

Portraits in Practice Iowa State University & Jet Propulsion Lab/Caltech  

E-Print Network [OSTI]

and Research at Siemens Corporation," led by Brian Berenbach, technical manager of the requirements engineering program, focuses on some recent projects and upcoming challenges. Siemens is one of the largest companies. Siemens Corporate Research (SCR) is part of Siemens Corporate Technology, the research arm of Siemens

Lutz, Robyn R.

75

1997A N N U A L R E P O R T Jet Propulsion Laboratory  

E-Print Network [OSTI]

to new positions on top of what is probably soft ice or ice-crusted water. observing NASA's Galileo spacecraft made two observations -- five months apart -- which revealed a new dark spot the size of Arizona a positive outcome: Missions are now being designed in a matter of a few weeks to a few months, in contrast

Waliser, Duane E.

76

JOEL AARON HUROWITZ Director's Fellow, Jet Propulsion Laboratory, California Institute of Technology (Caltech)  

E-Print Network [OSTI]

's Workbench Training Seminar 1999-2001 Thermal Ionization Mass Spectrometer Laboratory Manager 1994-Convener: American Geophysical Union Fall Meeting 2001-2006 Emission Spectrometer Laboratory Manager 2004 NASA), Div. of Geological and Planetary Sciences, Caltech 2005-2006 Undergraduate Research Mentor, Stony

Waliser, Duane E.

77

Thermoelectric Microdevice Fabrication Process and Evaluation at the Jet Propulsion Laboratory (JPL)  

E-Print Network [OSTI]

panel surface area, solar flux decreases accordingly (inverse square law) and loses effective power microdevices can convert rejected or waste heat into usable electric power, at moderate (200-500K) temperatures and future directions. Introduction As a spacecraft travels further away from the sun, for a defined solar

78

ASEPS-0 Testbed Interferometer control system Jet Propulsion Laboratory, California Institute of Technology  

E-Print Network [OSTI]

of complexity and programmatic risk. 3. CONTROL SYSTEM ARCHITECTURE OVERVIEW 3.1 Philosophy The overall approach

79

Development of a high power density motor for aircraft propulsion  

E-Print Network [OSTI]

are currently powered by heavy gas turbine engines that require fueling. The development of electric motors to replace gas turbines would be a big step towards accomplishing more efficient aircraft propulsion. The primary objective of this research extends...

Dibua, Imoukhuede Tim Odion

2007-04-25T23:59:59.000Z

80

Porous material and process development for electrospray propulsion applications  

E-Print Network [OSTI]

Ion electrospray propulsion devices rely on the transportation of ionic liquid propellant to emission regions where ions are extracted at high velocities. One such method involves the use of porous substrates to passively ...

Arestie, Steven Mark

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Molecular Dynamics Modeling of Ionic Liquids in Electrospray Propulsion  

E-Print Network [OSTI]

. Lozano June 2010 SSL # 6-10 #12;#12;Molecular Dynamics Modeling of Ionic Liquids in Electrospray Propulsion Nanako Takahashi, Paulo C. Lozano June 2010 SSL # 6-10 This work is based on the unaltered text

82

Electromagnetic Extraction and Annihilation of Antiprotons for Spacecraft Propulsion  

E-Print Network [OSTI]

. Zayas, Raymond J. Sedwick May, 2008 SSL # 3-08 #12;#12;Electromagnetic Extraction and Annihilation of Antiprotons for Spacecraft Propulsion Daniel A. Zayas, Raymond J. Sedwick May, 2008 SSL # 3-08 This work

83

A doubly-fed machine for propulsion applications  

E-Print Network [OSTI]

A doubly fed machine for propulsion applications is proposed, which, given the presence of AC and DC power sources, can be utilized in order to improve efficiency, weight, volume, and sizing of the rotor power electronics. ...

Tomovich, Michael S. (Michael Stephen)

2014-01-01T23:59:59.000Z

84

Novel turbomachinery concepts for highly integrated airframe/propulsion systems  

E-Print Network [OSTI]

Two novel turbomachinery concepts are presented as enablers to advanced flight missions requiring integrated airframe/propulsion systems. The first concept is motivated by thermal management challenges in low-to-high Mach ...

Shah, Parthiv N

2007-01-01T23:59:59.000Z

85

Molecular dynamics modeling of ionic liquids in electrospray propulsion  

E-Print Network [OSTI]

Micro-propulsion has been studied for many years due to its applications in small-to-medium sized spacecraft for precise satellite attitude control. Electrospray thrusters are promising thrusters built upon the state of ...

Takahashi, Nanako

2010-01-01T23:59:59.000Z

86

Emission spectroscopy for the study of electric propulsion plasmas  

E-Print Network [OSTI]

Typical electric propulsion devices rely on the acceleration of highly ionized plasmas to produce thrust at specific impulses unattainable with state-of-the-art chemical systems. This thesis examines the use of a miniaturized ...

Matlock, Taylor Scott

2009-01-01T23:59:59.000Z

87

Propulsion devices for locomotion at low-Reynolds number  

E-Print Network [OSTI]

We have designed, built, and tested three novel devices that use low-Reynolds number flows for self propulsion. The three-link swimmer is designed to swim through in a free viscous fluid using cyclic flipping motion of two ...

Chan, Brian, 1980-

2004-01-01T23:59:59.000Z

88

Design of repeating projectile toy based on bistable spring propulsion  

E-Print Network [OSTI]

Recently, bistable springs have been proven as a viable propulsion method for the standard 1.75" foam balls used in Nerf® projectile toys. This technology was developed at M.I.T. by William Fienup and Barry Kudrowitz, who ...

Blanco, Matthew C. (Matthew Corwin)

2007-01-01T23:59:59.000Z

89

Diffusion driven object propulsion in density stratified fluids  

E-Print Network [OSTI]

An experimental study was conducted in order to verify the appropriateness of a two dimensional model of the flow creating diffusion driven object propulsion in density stratified fluids. Initial flow field experiments ...

Lenahan, Conor (Conor P.)

2009-01-01T23:59:59.000Z

90

Application of ion electrospray propulsion to lunar and interplanetary missions  

E-Print Network [OSTI]

High specific impulse electric propulsion systems enable ambitious lunar and interplanetary missions that return a wealth of scientific data. Many of these technologies are difficult to scale down, meaning the spacecraft ...

Whitlock, Caleb W. (Caleb Wade)

2014-01-01T23:59:59.000Z

91

Multiple jet interactions  

E-Print Network [OSTI]

Type Designation Key Direction of Traverse: A - Axial R ? Radial A CON1 N (1) (3) (2) (2) Probe Type: N - Straight, a=O' S - Slant, a=45' (3) Configuration: CON1 CON2 CON3 CON4 CONS CON6 Jets h/D X/h 8 5. 0 16 2. 5 5. 33 7. 5 8 5. 0..., h/D=8. 0 and 2 Jets, h/D=8. 0. 0. 30 SYM INFORMATION: 8 RUN 24 RCON4N X/0 40 0. 25 oo 0. 20 0. 10 0. 05 0. 00 -0 4 -0 3 -0 2 -0. 1 0 0 0. 1 0 2 0 3 0 4 TyX Fig. 24 Distribution of Turbulence Intensity for 2 Jets, b/D=16. 0. 0. 30 BYN...

Hehr, Roger James

2012-06-07T23:59:59.000Z

92

Jet Substructure by Accident  

E-Print Network [OSTI]

We propose a new search strategy for high-multiplicity hadronic final states. When new particles are produced at threshold, the distribution of their decay products is approximately isotropic. If there are many partons in the final state, it is likely that several will be clustered into the same large-radius jet. The resulting jet exhibits substructure, even though the parent states are not boosted. This "accidental" substructure is a powerful discriminant against background because it is more pronounced for high-multiplicity signals than for QCD multijets. We demonstrate how to take advantage of accidental substructure to reduce backgrounds without relying on the presence of missing energy. As an example, we present the expected limits for several R-parity violating gluino decay topologies. This approach allows for the determination of QCD backgrounds using data-driven methods, which is crucial for the feasibility of any search that targets signatures with many jets and suppressed missing energy.

Timothy Cohen; Eder Izaguirre; Mariangela Lisanti; Hou Keong Lou

2013-04-23T23:59:59.000Z

93

Jet Substructure by Accident  

E-Print Network [OSTI]

We propose a new search strategy for high-multiplicity hadronic final states. When new particles are produced at threshold, the distribution of their decay products is approximately isotropic. If there are many partons in the final state, it is likely that several will be clustered into the same large-radius jet. The resulting jet exhibits substructure, even though the parent states are not boosted. This "accidental" substructure is a powerful discriminant against background because it is more pronounced for high-multiplicity signals than for QCD multijets. We demonstrate how to take advantage of accidental substructure to reduce backgrounds without relying on the presence of missing energy. As an example, we present the expected limits for several R-parity violating gluino decay topologies. This approach allows for the determination of QCD backgrounds using data-driven methods, which is crucial for the feasibility of any search that targets signatures with many jets and suppressed missing energy.

Cohen, Timothy; Lisanti, Mariangela; Lou, Hou Keong

2012-01-01T23:59:59.000Z

94

Organic vapor jet printing system  

DOE Patents [OSTI]

An organic vapor jet printing system includes a pump for increasing the pressure of an organic flux.

Forrest, Stephen R

2012-10-23T23:59:59.000Z

95

Gasoline Jet Fuels  

E-Print Network [OSTI]

C4n= Diesel Gasoline Jet Fuels C O C5: Xylose C6 Fermentation of sugars Biofuel "Nanobowls" are inorganic catalysts that could provide the selectivity for converting sugars to fuels IACT Proposes Synthetic, Inorganic Catalysts to Produce Biofuels Current Process

Kemner, Ken

96

Vortex diode jet  

DOE Patents [OSTI]

A fluid transfer system that combines a vortex diode with a jet ejector to transfer liquid from one tank to a second tank by a gas pressurization method having no moving mechanical parts in the fluid system. The vortex diode is a device that has a high resistance to flow in one direction and a low resistance to flow in the other.

Houck, Edward D. (Idaho Falls, ID)

1994-01-01T23:59:59.000Z

97

Jet quenching and elliptic flow  

E-Print Network [OSTI]

In jet quenching, a hard QCD parton, before fragmenting into a jet of hadrons, deposits a fraction of its energy in the medium, leading to suppressed production of high-$p_T$ hadrons. Assuming that the deposited energy quickly thermalizes, we simulate the subsequent hydrodynamic evolution of the QGP fluid. Explicit simulation of Au+Au collision with and without a quenching jet indicate that elliptic flow is greatly reduced in a jet event. The result can be used to identify the jet events in heavy ion collisions.

A. K. Chaudhuri

2007-08-29T23:59:59.000Z

98

Rapidity-Dependent Jet Vetoes  

E-Print Network [OSTI]

Jet vetoes are a prominent part of the signal selection in various analyses at the LHC. We discuss jet vetoes for which the transverse momentum of a jet is weighted by a smooth function of the jet rapidity. With a suitable choice of the rapidity-weighting function, such jet-veto variables can be factorized and resummed allowing for precise theory predictions. They thus provide a complementary way to divide phase space into exclusive jet bins. In particular, they provide a natural and theoretically clean way to implement a tight veto on central jets with the veto constraint getting looser for jets at increasingly forward rapidities. We mainly focus our discussion on the 0-jet case in color-singlet processes, using Higgs production through gluon fusion as a concrete example. For one of our jet-veto variables we compare the resummed theory prediction at NLL'+NLO with the recent differential cross section measurement by the ATLAS experiment in the $H\\to\\gamma\\gamma$ channel, finding good agreement. We also propose that these jet-veto variables can be measured and tested against theory predictions in other SM processes, such as Drell-Yan, diphoton, and weak diboson production.

Shireen Gangal; Maximilian Stahlhofen; Frank J. Tackmann

2014-12-15T23:59:59.000Z

99

Australian Science and Technology with Relevance to Beamed Energy Propulsion  

SciTech Connect (OSTI)

Although Australia has no Beamed Energy Propulsion programs at the present time, it is accomplishing significant scientific and technological activity that is of potential relevance to Beamed Energy Propulsion (BEP). These activities include: continual upgrading and enhancement of the Woomera Test Facility, Which is ideal for development and test of high power laser or microwave systems and the flight vehicles they would propel; collaborative development and test, with the US and UK of hypersonic missiles that embody many features needed by beam-propelled flight vehicles; hypersonic air breathing propulsion systems that embody inlet-engine-nozzle features needed for beam-riding agility by air breathing craft; and research on specially conditioned EM fields that could reduce beamed energy lost during atmospheric propagation.

Froning, H. David Jr [PO Box 180, Gumeracha SA 5233 (Australia)

2008-04-28T23:59:59.000Z

100

Self-propulsion of V-shape micro-robot  

E-Print Network [OSTI]

In this paper we study the self-propulsion of a symmetric V-shape micro-robot (or V-robot) which consists of three spheres connected by two arms with an angle between them; the arms' lengths and the angle are changing periodically. Using an asymptotic procedure containing two-timing method and a distinguished limit, we obtain analytic expressions for the self-propulsion velocity and Lighthill's efficiency. The calculations show that a version of V-robot, aligned perpendicularly to the direction of self-swimming, is both the fastest one and the most efficient one. We have also shown that such $V$-robot is faster and more efficient than a linear three-sphere micro-robot. At the same time the maximal self-propulsion velocity of V-robots is significantly smaller than that of comparable microorganisms.

Vladimir A. Vladimirov

2012-09-13T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

A survey of processes for producing hydrogen fuel from different sources for automotive-propulsion fuel cells  

SciTech Connect (OSTI)

Seven common fuels are compared for their utility as hydrogen sources for proton-exchange-membrane fuel cells used in automotive propulsion. Methanol, natural gas, gasoline, diesel fuel, aviation jet fuel, ethanol, and hydrogen are the fuels considered. Except for the steam reforming of methanol and using pure hydrogen, all processes for generating hydrogen from these fuels require temperatures over 1000 K at some point. With the same two exceptions, all processes require water-gas shift reactors of significant size. All processes require low-sulfur or zero-sulfur fuels, and this may add cost to some of them. Fuels produced by steam reforming contain {approximately}70-80% hydrogen, those by partial oxidation {approximately}35-45%. The lower percentages may adversely affect cell performance. Theoretical input energies do not differ markedly among the various processes for generating hydrogen from organic-chemical fuels. Pure hydrogen has severe distribution and storage problems. As a result, the steam reforming of methanol is the leading candidate process for on-board generation of hydrogen for automotive propulsion. If methanol unavailability or a high price demands an alternative process, steam reforming appears preferable to partial oxidation for this purpose.

Brown, L.F.

1996-03-01T23:59:59.000Z

102

Advanced ignition and propulsion technology program  

SciTech Connect (OSTI)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Reliable engine re-ignition plays a crucial role in enabling commercial and military aircraft to fly safely at high altitudes. This project addressed research elements critical to the optimization of laser-based igniter. The effort initially involved a collaborative research and development agreement with B.F. Goodrich Aerospace and Laser Fare, Inc. The work involved integrated experiments with theoretical modeling to provide a basic understanding of the chemistry and physics controlling the laser-induced ignition of fuel aerosols produced by turbojet engine injectors. In addition, the authors defined advanced laser igniter configurations that minimize laser packaging size, weight, complexity and power consumption. These innovative ignition concepts were shown to reliably ignite jet fuel aerosols over a broad range of fuel/air mixture and a t fuel temperatures as low as -40 deg F. The demonstrated fuel ignition performance was highly superior to that obtained by the state-of-the-art, laser-spark ignition method utilizing comparable laser energy. The authors also developed a laser-based method that effectively removes optically opaque deposits of fuel hydrocarbon combustion residues from laser window surfaces. Seven patents have been either issued or are pending that resulted from the technology developments within this project.

Oldenborg, R.; Early, J.; Lester, C.

1998-11-01T23:59:59.000Z

103

Propulsion Mechanisms for Leidenfrost Solids on Ratchet Surfaces  

E-Print Network [OSTI]

We propose a model for the propulsion of Leidenfrost solids on ratchets based on viscous drag due to the flow of evaporating vapor. The model assumes pressure-driven flow described by the Navier-Stokes equations and is mainly studied in lubrication approximation. A scaling expression is derived for the dependence of the propulsive force on geometric parameters of the ratchet surface and properties of the sublimating solid. We show that the model results as well as the scaling law compare favorably with experiments and are able to reproduce the experimentally observed scaling with the size of the solid.

Baier, Tobias; Herbert, Stefan; Hardt, Steffen; Quere, David

2012-01-01T23:59:59.000Z

104

Tutorial on nuclear thermal propulsion safety for Mars  

SciTech Connect (OSTI)

Safety is the prime design requirement for nuclear thermal propulsion (NTP). It must be built in at the initiation of the design process. An understanding of safety concerns is fundamental to the development of nuclear rockets for manned missions to Mars and many other applications that will be enabled or greatly enhanced by the use of nuclear propulsion. To provide an understanding of the basic issues, a tutorial has been prepared. This tutorial covers a range of topics including safety requirements and approaches to meet these requirements, risk and safety analysis methodology, NERVA reliability and safety approach, and life cycle risk assessments.

Buden, D.

1992-01-01T23:59:59.000Z

105

Tutorial on nuclear thermal propulsion safety for Mars  

SciTech Connect (OSTI)

Safety is the prime design requirement for nuclear thermal propulsion (NTP). It must be built in at the initiation of the design process. An understanding of safety concerns is fundamental to the development of nuclear rockets for manned missions to Mars and many other applications that will be enabled or greatly enhanced by the use of nuclear propulsion. To provide an understanding of the basic issues, a tutorial has been prepared. This tutorial covers a range of topics including safety requirements and approaches to meet these requirements, risk and safety analysis methodology, NERVA reliability and safety approach, and life cycle risk assessments.

Buden, D.

1992-08-01T23:59:59.000Z

106

Heavy Vehicle Propulsion Materials Program: Progress and Highlights  

SciTech Connect (OSTI)

The Heavy Vehicle Propulsion Materials Program was begun in 1997 to support the enabling materials needs of the DOE Office of Heavy Vehicle Technologies (OHVT). The technical agenda for the program grew out of the technology roadmap for the OHVT and includes efforts in materials for: fuel systems, exhaust aftertreatment, valve train, air handling, structural components, electrochemical propulsion, natural gas storage, and thermal management. A five-year program plan was written in early 2000, following a stakeholders workshop. The technical issues and planned and ongoing projects are discussed. Brief summaries of several technical highlights are given.

D. Ray Johnson; Sidney Diamond

2000-06-19T23:59:59.000Z

107

Naval ship propulsion and electric power systems selection for optimal fuel consumption  

E-Print Network [OSTI]

Although propulsion and electric power systems selection is an important part of naval ship design, respective decisions often have to be made without detailed ship knowledge (resistance, propulsors, etc.). Propulsion and ...

Sarris, Emmanouil

2011-01-01T23:59:59.000Z

108

High performance path following for marine vehicles using azimuthing podded propulsion  

E-Print Network [OSTI]

Podded propulsion systems offer greater maneuvering possibilities for marine vehicles than conventional shaft and rudder systems. As the propulsion unit rotates about its vertical axis to a specified azimuth angle, the ...

Greytak, Matthew B. (Matthew Bardeen)

2006-01-01T23:59:59.000Z

109

E-Print Network 3.0 - automotive-propulsion fuel cells Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

automotive-propulsion fuel cells Search Powered by Explorit Topic List Advanced Search Sample search results for: automotive-propulsion fuel cells Page: << < 1 2 3 4 5 > >> 1 ORNL...

110

E-Print Network 3.0 - ab-thermonuclear space propulsion Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

thermonuclear space propulsion Search Powered by Explorit Topic List Advanced Search Sample search results for: ab-thermonuclear...

111

NASA/DOE/DOD nuclear propulsion technology planning: Summary of FY 1991 interagency panel results  

SciTech Connect (OSTI)

Interagency (NASA/DOE/DOD) technical panels worked in 1991 to evaluate critical nuclear propulsion issues, compare nuclear propulsion concepts for a manned Mars mission on a consistent basis, and to continue planning a technology development project for the Space Exploration Initiative (SEI). Panels were formed to address mission analysis, nuclear facilities, safety policy, nuclear fuels and materials, nuclear electric propulsion technology, and nuclear thermal propulsion technology. A summary of the results and recommendations of the panels is presented.

Clark, J.S.; Wickenheiser, T.J.; Doherty, M.P.; Marshall, A.; Bhattacharryya, S.K.; Warren, J.

1992-01-01T23:59:59.000Z

112

International Electric Propulsion Conference, The George Washington University, USA October 6 10, 2013  

E-Print Network [OSTI]

1 The 33rd International Electric Propulsion Conference, The George Washington University, USA Electric Propulsion Conference, The George Washington University · Washington, D.C. · USA October 6 ­ 10.t.yim@nasa.gov. #12;2 The 33rd International Electric Propulsion Conference, The George Washington University, USA

Walker, Mitchell

113

Modified shielding jet model for twin-jet shielding analysis  

E-Print Network [OSTI]

the slowing of the jet flow due to turbulent mixing and entrainment of particles from the surrounding medium. The empirical formulations and velocity profiles derived for the respective regions of the jet consider this increase in entrained fluid... velocity profiles are integrated over their respective cross sections of the shielding jet to determine the total volumetric flowrate at the specified locations. A slug flow velocity approximation is then determined for each of the desired downstream...

Gilbride, Jennifer Frances

2012-06-07T23:59:59.000Z

114

Emissions and Performance Tradeoffs for Advanced Marine Diesel Propulsion  

E-Print Network [OSTI]

the turbocharger and the diesel engine in steady-state 5]. Secondly, it modi es the power transfer to the turbineEmissions and Performance Tradeoffs for Advanced Marine Diesel Propulsion Anna Stefanopoulouy is designed that reduces smoke generation on an experimental marine Diesel engine equipped with a variable

Stefanopoulou, Anna

115

Design, Analysis, and Simulation of Rocket Propulsion System  

E-Print Network [OSTI]

. The program currently provides a symbolic link in the form of a button on the output page which will open Unigraphics NX CAD program. The post-processing simulation of the rocket propulsion system is done in a computational fluid dynamics (CFD) program...

Kulhanek, Sarah Logan

2012-08-31T23:59:59.000Z

116

Jet initiation of PBX 9502  

SciTech Connect (OSTI)

This report details the progress of an effort to determine the quantitative aspects of the initiation of PBX 9502 (95% TATB, 5% Kel-F 800) by copper jets. The particular jet used was that produced by the LAW warhead (66-mm diameter, 42/sup 0/ angle cone, copper-lined, conical shaped charge). Fifteen experiments, in various configurations, have been fired to define the essential parameters for quantitatively measuring the jet performance and initiation of bare PBX 9502. 7 refs., 8 figs.

McAfee, J.M.

1987-07-01T23:59:59.000Z

117

Buoyant jet behavior in confined regions  

E-Print Network [OSTI]

Previous confined jet studies have emphasized the behavior of non-buoyant jets inside ducts or near plane boundaries (Coanda effect). Buoyancy, however, is a major factor in the confined jet behavior experienced in many ...

Fry, David J.

1981-01-01T23:59:59.000Z

118

Mercury Jet Studies Tristan Davenne  

E-Print Network [OSTI]

Mercury Jet Studies Tristan Davenne Rutherford Appleton Laboratory Joint UKNF, INO, UKIERI meeting mercury target and reported a radial velocity at surface of mercury jet due to proton beam is 36m/s #12;Numerical simulation of Sievers & Pugnat Result Click on image above to watch video of 2cm mercury target

McDonald, Kirk

119

OPENING ANGLES OF COLLAPSAR JETS  

SciTech Connect (OSTI)

We investigate the jet propagation and breakout from the stellar progenitor for gamma-ray burst (GRB) collapsars by performing two-dimensional relativistic hydrodynamic simulations and analytical modeling. We find that the jet opening angle is given by ?{sub j} ? 1/5?{sub 0} and infer the initial Lorentz factor of the jet at the central engine, ?{sub 0}, is a few for existing observations of ?{sub j}. The jet keeps the Lorentz factor low inside the star by converging cylindrically via collimation shocks under the cocoon pressure and accelerates at jet breakout before the free expansion to a hollow-cone structure. In this new picture, the GRB duration is determined by the sound crossing time of the cocoon, after which the opening angle widens, reducing the apparent luminosity. Some bursts violating the maximum opening angle ?{sub j,{sub max}} ? 1/5 ? 12° imply the existence of a baryon-rich sheath or a long-acting jet. We can explain the slopes in both Amati and Yonetoku spectral relations using an off-centered photosphere model, if we make only one assumption that the total jet luminosity is proportional to the initial Lorentz factor of the jet. We also numerically calibrate the pre-breakout model (Bromberg et al.) for later use.

Mizuta, Akira; Ioka, Kunihito [Theory Center, Institute of Particle and Nuclear Studies, KEK, Tsukuba 305-0801 (Japan)

2013-11-10T23:59:59.000Z

120

Assessment of Space Nuclear Thermal Propulsion Facility and Capability Needs  

SciTech Connect (OSTI)

The development of a Nuclear Thermal Propulsion (NTP) system rests heavily upon being able to fabricate and demonstrate the performance of a high temperature nuclear fuel as well as demonstrating an integrated system prior to launch. A number of studies have been performed in the past which identified the facilities needed and the capabilities available to meet the needs and requirements identified at that time. Since that time, many facilities and capabilities within the Department of Energy have been removed or decommissioned. This paper provides a brief overview of the anticipated facility needs and identifies some promising concepts to be considered which could support the development of a nuclear thermal propulsion system. Detailed trade studies will need to be performed to support the decision making process.

James Werner

2014-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Scoping calculations of power sources for nuclear electric propulsion  

SciTech Connect (OSTI)

This technical memorandum describes models and calculational procedures to fully characterize the nuclear island of power sources for nuclear electric propulsion. Two computer codes were written: one for the gas-cooled NERVA derivative reactor and the other for liquid metal-cooled fuel pin reactors. These codes are going to be interfaced by NASA with the balance of plant in order to making scoping calculations for mission analysis.

Difilippo, F.C. [Oak Ridge National Lab., TN (United States)] [Oak Ridge National Lab., TN (United States)

1994-05-01T23:59:59.000Z

122

Performance and Controllability of Pulsed Ion Beam Ablation Propulsion  

SciTech Connect (OSTI)

We propose novel propulsion driven by ablation plasma pressures produced by the irradiation of pulsed ion beams onto a propellant. The ion beam ablation propulsion demonstrates by a thin foil (50 {mu}mt), and the flyer velocity of 7.7 km/s at the ion beam energy density of 2 kJ/cm2 adopted by using the Time-of-flight method is observed numerically and experimentally. We estimate the performance of the ion beam ablation propulsion as specific impulse of 3600 s and impulse bit density of 1700 Ns/m2 obtained from the demonstration results. In the numerical analysis, a one-dimensional hydrodynamic model with ion beam energy depositions is used. The control of the ion beam kinetic energy is only improvement of the performance but also propellant consumption. The spacecraft driven by the ion beam ablation provides high performance efficiency with short-pulsed ion beam irradiation. The numerical results of the advanced model explained latent heat and real gas equation of state agreed well with experimental ones over a wide range of the incident ion beam energy density.

Yazawa, Masaru; Buttapeng, Chainarong; Harada, Nobuhiro [Nagaoka University of Technology, Department of Electrical Engineering, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 (Japan); Suematsu, Hisayuki; Jiang Weihua; Yatsui, Kiyoshi [Nagaoka University of Technology, Extreme Energy-Density Research Institute, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188 (Japan)

2006-05-02T23:59:59.000Z

123

Full fuel-cycle comparison of forklift propulsion systems.  

SciTech Connect (OSTI)

Hydrogen has received considerable attention as an alternative to fossil fuels. The U.S. Department of Energy (DOE) investigates the technical and economic feasibility of promising new technologies, such as hydrogen fuel cells. A recent report for DOE identified three near-term markets for fuel cells: (1) Emergency power for state and local emergency response agencies, (2) Forklifts in warehousing and distribution centers, and (3) Airport ground support equipment markets. This report examines forklift propulsion systems and addresses the potential energy and environmental implications of substituting fuel-cell propulsion for existing technologies based on batteries and fossil fuels. Industry data and the Argonne Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model are used to estimate full fuel-cycle emissions and use of primary energy sources, back to the primary feedstocks for fuel production. Also considered are other environmental concerns at work locations. The benefits derived from using fuel-cell propulsion are determined by the sources of electricity and hydrogen. In particular, fuel-cell forklifts using hydrogen made from the reforming of natural gas had lower impacts than those using hydrogen from electrolysis.

Gaines, L. L.; Elgowainy, A.; Wang, M. Q.; Energy Systems

2008-11-05T23:59:59.000Z

124

Vehicle configuration options using nuclear propulsion for Mars missions  

SciTech Connect (OSTI)

The solid core nuclear thermal rocket (NTR) provides an attractive means of providing the propulsive force needed to accomplish a wide array of space missions. With its factor of two or more advantage in Isp over chemical engines, nuclear propulsion provides the opportunity to accomplish space missions which are impractical by other means. This paper focuses on the use of a nuclear thermal rocket to accomplish a variety of space missions with emphasis on the manned Mars mission. The particle bed reactor (PBR) type nuclear engine was chosen as the baseline engine used to conduct the present study because of its perceived versatility over other nuclear propulsion systems in conducting a wide variety of tasks. This study baselines a particle bed reactor engine with an engine thrust-to-weight ratio ([similar to]11.5) and a specific impulse of [similar to]950 s. It is shown that a PBR engine of this type will offer distinct advantages over the larger and heavier NERVA type nuclear engines.

Emrich, W.J. Jr. (NASA-Marshall Space Flight Center, Huntsville, Alabama 35812 (United States))

1993-01-20T23:59:59.000Z

125

REIMR - A Process for Utilizing Liquid Rocket Propulsion-Oriented 'Lessons Learned' to Mitigate Development Risk in Nuclear Thermal Propulsion  

SciTech Connect (OSTI)

This paper is a summary overview of a study conducted at the NASA Marshall Space Flight Center (NASA-MSFC) during the initial phases of the Space Launch Initiative (SLI) program to evaluate a large number of technical problems associated with the design, development, test, evaluation and operation of several major liquid propellant rocket engine systems (i.e., SSME, Fastrac, J-2, F-1). One of the primary results of this study was the identification of the 'Fundamental Root Causes' that enabled the technical problems to manifest, and practices that can be implemented to prevent them from recurring in future propulsion system development efforts, such as that which is currently envisioned in the field of nuclear thermal propulsion (NTP). This paper will discus the Fundamental Root Causes, cite some examples of how the technical problems arose from them, and provide a discussion of how they can be mitigated or avoided in the development of an NTP system.

Ballard, Richard O. [Nuclear and Advanced Propulsion Systems Engineering Branch, NASA Marshall Space Flight Center, AL 35812 (United States)

2006-01-20T23:59:59.000Z

126

Micromachined chemical jet dispenser  

DOE Patents [OSTI]

A dispenser is disclosed for chemical fluid samples that need to be precisely ejected in size, location, and time. The dispenser is a micro-electro-mechanical systems (MEMS) device fabricated in a bonded silicon wafer and a substrate, such as glass or silicon, using integrated circuit-like fabrication technology which is amenable to mass production. The dispensing is actuated by ultrasonic transducers that efficiently produce a pressure wave in capillaries that contain the chemicals. The 10-200 {micro}m diameter capillaries can be arranged to focus in one spot or may be arranged in a larger dense linear array (ca. 200 capillaries). The dispenser is analogous to some ink jet print heads for computer printers but the fluid is not heated, thus not damaging certain samples. Major applications are in biological sample handling and in analytical chemical procedures such as environmental sample analysis, medical lab analysis, or molecular biology chemistry experiments. 4 figs.

Swierkowski, S.P.

1999-03-02T23:59:59.000Z

127

Micromachined chemical jet dispenser  

DOE Patents [OSTI]

A dispenser for chemical fluid samples that need to be precisely ejected in size, location, and time. The dispenser is a micro-electro-mechanical systems (MEMS) device fabricated in a bonded silicon wafer and a substrate, such as glass or silicon, using integrated circuit-like fabrication technology which is amenable to mass production. The dispensing is actuated by ultrasonic transducers that efficiently produce a pressure wave in capillaries that contain the chemicals. The 10-200 .mu.m diameter capillaries can be arranged to focus in one spot or may be arranged in a larger dense linear array (.about.200 capillaries). The dispenser is analogous to some ink jet print heads for computer printers but the fluid is not heated, thus not damaging certain samples. Major applications are in biological sample handling and in analytical chemical procedures such as environmental sample analysis, medical lab analysis, or molecular biology chemistry experiments.

Swierkowski, Steve P. (Livermore, CA)

1999-03-02T23:59:59.000Z

128

Water cooled steam jet  

DOE Patents [OSTI]

A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed therebetween. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock.

Wagner, Jr., Edward P. (Idaho Falls, ID)

1999-01-01T23:59:59.000Z

129

Jets in heavy ion collisions with ATLAS  

E-Print Network [OSTI]

The energy loss of high-p_T partons provides insight into the transport properties of the medium created in relativistic heavy ion collisions. Evidence for this energy loss was first experimentally established through observation of high-p_T hadron suppression at RHIC. More recently, measurements of fully reconstructed jets have been performed at the LHC. In this summary the latest experimental results from the ATLAS collaboration on jet suppression are presented. In particular the jet suppression in inclusive jet yields, path length dependence of the jet suppression, photon-jet and Z^0-jet correlations, heavy flavor suppression, and jet fragmentation are discussed. These results establish qualitative features of the jet quenching mechanism as experimental fact and provide constraints on models of jet energy loss.

Martin Spousta; for the ATLAS Collaboration

2012-11-14T23:59:59.000Z

130

How to calibrate the jet energy scale?  

SciTech Connect (OSTI)

Top quarks dominantly decay into b-quark jets and W bosons, and the W bosons often decay into jets, thus the precise determination of the jet energy scale is crucial in measurements of many top quark properties. I present the strategies used by the CDF and D0 collaborations to determine the jet energy scale. The various cross checks performed to verify the determined jet energy scale and evaluate its systematic uncertainty are also discussed.

Hatakeyama, K.; /Rockefeller U.

2006-01-01T23:59:59.000Z

131

A theory for radial jet reattachment flow  

E-Print Network [OSTI]

, the velocity profile and mass entrainment are given accordrng to Goertler's t. wo- dimensional free jet theory. His analysrs of a free jet also assumes that. the turbulent eddy viscosity is constant ar ross the jet. (6) For the case of laminar flow... of total jet momentum. Laminar jet flow is approximated using Schlichting's velocity profile, whereas turbulent flow calculations are made assuming Goertler's velocity profile. Momentum integral principles are applied to the flow at reattachment...

Hadden, Lynne Loise

2012-06-07T23:59:59.000Z

132

Latest jet results from the Tevatron  

SciTech Connect (OSTI)

A brief overview of the latest status of jet physics studies at the Tevatron in proton-antiproton collisions at {radical}s = 1.96 TeV is presented. In particular, measurements of the inclusive jet production cross-section, dijet production and searches for new physics, the ratio of the 3-jet to 2-jet production cross-sections, and the three-jet mass are discussed.

Price, Darren D.

2010-05-01T23:59:59.000Z

133

Integrated null-flux suspension and multiphase propulsion system for magnetically-levitated vehicles  

DOE Patents [OSTI]

This report discusses a propulsion and stabilization system comprising a series of figure 8 coils mounted vertically on the walls of the guideway to provide suspension, lateral guidance and propulsion of a magnetically levitated vehicle. This system further allows for altering the magnetic field effects by changing the relative position of the loops comprising the figure 8 coils either longitudinally and/or vertically with resulting changes in the propulsion, the vertical stability, and the suspension.

Rote, D.M.; He, Jianliang; Johnson, L.R.

1992-01-01T23:59:59.000Z

134

Integrated null-flux suspension and multiphase propulsion system for magnetically-levitated vehicles  

DOE Patents [OSTI]

A propulsion and stabilization system are described comprising a series of coils mounted vertically on the walls of the guideway to provide suspension, lateral guidance, and propulsion of a magnetically levitated vehicle. This system further allows for altering the magnetic field effects by changing the relative position of the loops comprising the coils either longitudinally and/or vertically with resulting changes in the propulsion, the vertical stability, and the suspension. 8 figures.

Rote, D.M.; He, J.; Johnson, L.R.

1994-01-04T23:59:59.000Z

135

Radial flow pulse jet mixer  

DOE Patents [OSTI]

The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

VanOsdol, John G.

2013-06-25T23:59:59.000Z

136

High Fidelity Radiative Thermal Transport Simulations of a Scramjet Propulsion System.  

E-Print Network [OSTI]

??Scramjets are a type of air breathing propulsion system that have the potential to efficiently provide thrust for atmospheric vehicles at high speeds. Defining the… (more)

Irvine, Adam Glenn

2013-01-01T23:59:59.000Z

137

E-Print Network 3.0 - aircraft propulsion systems Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and Astronautics School of Engineering Summary: Aircraft Initiative, Robust Turbine Engine Design, Propulsion, Active Control of Aeromechanical Systems... an oxidizer, an...

138

E-Print Network 3.0 - advanced propulsion concepts Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

on the field emission principle... advanced technology in power conversion. The main advantages of a propulsion system based on the field emis... AS THRUSTERS FOR ELECTRIC SPACE...

139

E-Print Network 3.0 - advanced electric propulsion Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Powered by Explorit Topic List Advanced Search Sample search results for: advanced electric propulsion Page: << < 1 2 3 4 5 > >> 1 Department of Aeronautics and Astronautics...

140

E-Print Network 3.0 - advanced propulsion engine Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

System Cleaner, smarter power for transit Summary: engine Propulsion power arrangement optimization & FC response Accessory loads, including balance... W Develop Fleet...

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Summer Undergraduate Research Opportunities in the Electric Propulsion and Plasmadynamics Laboratory (EPPDyL)*  

E-Print Network [OSTI]

will then be detected using a mass spectrometer. Prior experience with basic electronic instruments is desirableSummer Undergraduate Research Opportunities in the Electric Propulsion and Plasmadynamics

142

E-Print Network 3.0 - auxiliary propulsion applications Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

MAE Seminar Series Combustion Chemistry and Laser Diagnostics for Aero-Propulsion and Energy... Applications Matthew A. Oehlschlaeger Rensselaer Polytechnic Institute Future...

143

E-Print Network 3.0 - advanced embedded propulsion Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

12;EPA Sensor... inserts 72 layer drift tube created72 layer drift tube created 12;MicroMicro--Propulsion ... Source: Boise State University, Center for...

144

Numerical Simulations of Bouncing Jets  

E-Print Network [OSTI]

Bouncing jets are fascinating phenomenons occurring under certain conditions when a jet impinges on a free surface. This effect is observed when the fluid is Newtonian and the jet falls in a bath undergoing a solid motion. It occurs also for non-Newtonian fluids when the jets falls in a vessel at rest containing the same fluid. We investigate numerically the impact of the experimental setting and the rheological properties of the fluid on the onset of the bouncing phenomenon. Our investigations show that the occurrence of a thin lubricating layer of air separating the jet and the rest of the liquid is a key factor for the bouncing of the jet to happen. The numerical technique that is used consists of a projection method for the Navier-Stokes system coupled with a level set formulation for the representation of the interface. The space approximation is done with adaptive finite elements. Adaptive refinement is shown to be very important to capture the thin layer of air that is responsible for the bouncing.

Bonito, Andrea; Lee, Sanghyun

2015-01-01T23:59:59.000Z

145

Phase 1 Space Fission Propulsion Energy Source Design  

SciTech Connect (OSTI)

Fission technology can enable rapid, affordable access to any point in the solar system. If fission propulsion systems are to be developed to their full potential; however, near-term customers must be identified and initial fission systems successfully developed, launched, and operated. Studies conducted in fiscal year 2001 (IISTP, 2001) show that fission electric propulsion (FEP) systems with a specific mass at or below 50 kg/kWjet could enhance or enable numerous robotic outer solar system missions of interest. At the required specific mass, it is possible to develop safe, affordable systems that meet mission requirements. To help select the system design to pursue, eight evaluation criteria were identified: system integration, safety, reliability, testability, specific mass, cost, schedule, and programmatic risk. A top-level comparison of four potential concepts was performed: a Testable, Passive, Redundant Reactor (TPRR), a Testable Multi-Cell In-Core Thermionic Reactor (TMCT), a Direct Gas Cooled Reactor (DGCR), and a Pumped Liquid Metal Reactor (PLMR). Development of any of the four systems appears feasible. However, for power levels up to at least 500 kWt (enabling electric power levels of 125-175 kWe, given 25-35% power conversion efficiency) the TPRR has advantages related to several criteria and is competitive with respect to all. Hardware-based research and development has further increased confidence in the TPRR approach. Successful development and utilization of a 'Phase 1' fission electric propulsion system will enable advanced Phase 2 and Phase 3 systems capable of providing rapid, affordable access to any point in the solar system. (authors)

Houts, Mike; Van Dyke, Melissa; Godfroy, Tom; Pedersen, Kevin; Martin, James; Dickens, Ricky; Salvail, Pat; Hrbud, Ivana; Carter, Robert [NASA MSFC, TD40, Marshall Space Flight Center, Alabama, 35812 (United States)

2002-07-01T23:59:59.000Z

146

ADVANCED RADIOISOTOPE HEAT SOURCE AND PROPULSION SYSTEMS FOR PLANETARY EXPLORATION  

SciTech Connect (OSTI)

The exploration of planetary surfaces and atmospheres may be enhanced by increasing the range and mobility of a science platform. Fundamentally, power production and availability of resources are limiting factors that must be considered for all science and exploration missions. A novel power and propulsion system is considered and discussed with reference to a long-range Mars surface exploration mission with in-situ resource utilization. Significance to applications such as sample return missions is also considered. Key material selections for radioisotope encapsulation techniques are presented.

R. C. O'Brien; S. D. Howe; J. E. Werner

2010-09-01T23:59:59.000Z

147

The Use of Steady and Pulsed Detonations for Propulsion Systems  

SciTech Connect (OSTI)

Objectives of the ODWE concept studies are: demonstrate the feasibility of the oblique detonation wave engine (ODWE) for hypersonic propulsion; demonstrate the existance and stability of an oblique detonation wave in hypersonic wind tunnels; develop engineering codes which predict the performance characteristics of the ODWE including specific impulse and thrust coefficients for various operating conditions; develop multi-dimensional computer codes which can model all aspects of the ODWE including fuel injection, mixing, ignition, combustion and expansion with fully detailed chemical kinetics and turbulence models; and validate the codes with experimental data use the simulations to predict the ODWE performance for conditions not easily obtained in wind tunnels.

Adelman, H.G.; Menees, G.P.; Cambier, J.L.; Bowles, J.V.

1996-02-01T23:59:59.000Z

148

Plasma jet ignition device  

DOE Patents [OSTI]

An ignition device of the plasma jet type is disclosed. The device has a cylindrical cavity formed in insulating material with an electrode at one end. The other end of the cylindrical cavity is closed by a metal plate with a small orifice in the center which plate serves as a second electrode. An arc jumping between the first electrode and the orifice plate causes the formation of a highly-ionized plasma in the cavity which is ejected through the orifice into the engine cylinder area to ignite the main fuel mixture. Two improvements are disclosed to enhance the operation of the device and the length of the plasma plume. One improvement is a metal hydride ring which is inserted in the cavity next to the first electrode. During operation, the high temperature in the cavity and the highly excited nature of the plasma breaks down the metal hydride, liberating hydrogen which acts as an additional fuel to help plasma formation. A second improvement consists of a cavity insert containing a plurality of spaced, metal rings. The rings act as secondary spark gap electrodes reducing the voltage needed to maintain the initial arc in the cavity.

McIlwain, Michael E. (Franklin, MA); Grant, Jonathan F. (Wayland, MA); Golenko, Zsolt (North Reading, MA); Wittstein, Alan D. (Fairfield, CT)

1985-01-15T23:59:59.000Z

149

Radioisotope Electric Propulsion for Deep Space Sample Return  

SciTech Connect (OSTI)

The need to answer basic questions regarding the origin of the Solar System will motivate robotic sample return missions to destinations like Pluto, its satellite Charon, and objects in the Kuiper belt. To keep the mission duration short enough to be of interest, sample return from objects farther out in the Solar System requires increasingly higher return velocities. A sample return mission involves several complicated steps to reach an object and obtain a sample, but only the interplanetary return phase of the mission is addressed in this paper. Radioisotope electric propulsion is explored in this parametric study as a means to propel small, dedicated return vehicles for transferring kilogram-size samples from deep space to Earth. Return times for both Earth orbital rendezvous and faster, direct atmospheric re-entry trajectories are calculated for objects as far away as 100 AU. Chemical retro-rocket braking at Earth is compared to radioisotope electric propulsion but the limited deceleration capability of chemical rockets forces the return trajectories to be much slower.

Noble, Robert J.; /SLAC

2009-07-14T23:59:59.000Z

150

Hydrodynamic Efficiency of Ablation Propulsion with Pulsed Ion Beam  

SciTech Connect (OSTI)

This paper presents the hydrodynamic efficiency of ablation plasma produced by pulsed ion beam on the basis of the ion beam-target interaction. We used a one-dimensional hydrodynamic fluid compressible to study the physics involved namely an ablation acceleration behavior and analyzed it as a rocketlike model in order to investigate its hydrodynamic variables for propulsion applications. These variables were estimated by the concept of ablation driven implosion in terms of ablated mass fraction, implosion efficiency, and hydrodynamic energy conversion. Herein, the energy conversion efficiency of 17.5% was achieved. In addition, the results show maximum energy efficiency of the ablation process (ablation efficiency) of 67% meaning the efficiency with which pulsed ion beam energy-ablation plasma conversion. The effects of ion beam energy deposition depth to hydrodynamic efficiency were briefly discussed. Further, an evaluation of propulsive force with high specific impulse of 4000s, total impulse of 34mN and momentum to energy ratio in the range of {mu}N/W was also analyzed.

Buttapeng, Chainarong; Yazawa, Masaru; Harada, Nobuhiro [Department of Electrical Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka 940-2188 (Japan); Suematsu, Hisayuki; Jiang Weihua; Yatsui, Kiyoshi [Extreme Energy-Density Research Institute, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka 940-2188 (Japan)

2006-05-02T23:59:59.000Z

151

Beamed Core Antimatter Propulsion: Engine Design and Optimization  

E-Print Network [OSTI]

A conceptual design for beamed core antimatter propulsion is reported, where electrically charged annihilation products directly generate thrust after being deflected and collimated by a magnetic nozzle. Simulations were carried out using the Geant4 (Geometry and tracking) software toolkit released by the CERN accelerator laboratory for Monte Carlo simulation of the interaction of particles with matter and fields. Geant permits a more sophisticated and comprehensive design and optimization of antimatter engines than the software environment for simulations reported by prior researchers. The main finding is that effective exhaust speeds Ve ~ 0.69c (where c is the speed of light) are feasible for charged pions in beamed core propulsion, a major improvement over the Ve ~ 0.33c estimate based on prior simulations. The improvement resulted from optimization of the geometry and the field configuration of the magnetic nozzle. Moreover, this improved performance is realized using a magnetic field on the order of 10 T at the location of its highest magnitude. Such a field could be produced with today's technology, whereas prior nozzle designs anticipated and required major advances in this area. The paper also briefly reviews prospects for production of the fuel needed for a beamed core engine.

Ronan Keane; Wei-Ming Zhang

2012-05-16T23:59:59.000Z

152

Nuclear rockets: High-performance propulsion for Mars  

SciTech Connect (OSTI)

A new impetus to manned Mars exploration was introduced by President Bush in his Space Exploration Initiative. This has led, in turn, to a renewed interest in high-thrust nuclear thermal rocket propulsion (NTP). The purpose of this report is to give a brief tutorial introduction to NTP and provide a basic understanding of some of the technical issues in the realization of an operational NTP engine. Fundamental physical principles are outlined from which a variety of qualitative advantages of NTP over chemical propulsion systems derive, and quantitative performance comparisons are presented for illustrative Mars missions. Key technologies are described for a representative solid-core heat-exchanger class of engine, based on the extensive development work in the Rover and NERVA nuclear rocket programs (1955 to 1973). The most driving technology, fuel development, is discussed in some detail for these systems. Essential highlights are presented for the 19 full-scale reactor and engine tests performed in these programs. On the basis of these tests, the practicality of graphite-based nuclear rocket engines was established. Finally, several higher-performance advanced concepts are discussed. These have received considerable attention, but have not, as yet, developed enough credibility to receive large-scale development.

Watson, C.W.

1994-05-01T23:59:59.000Z

153

RESEARCH TRAINING GROUP GRK 1095/1: "AERO-THERMODYNAMIC DESIGN OF A SCRAMJET PROPULSION SYSTEM"  

E-Print Network [OSTI]

RESEARCH TRAINING GROUP GRK 1095/1: "AERO-THERMODYNAMIC DESIGN OF A SCRAMJET PROPULSION SYSTEM" U conception. In this context only the use of a scramjet-propulsion system meets all the aerodynamic it must be mentioned that scramjet-technologies are one of the key technologies for hypersonic flight

154

The 32nd International Electric Propulsion Conference, Wiesbaden, Germany September 11 15, 2011  

E-Print Network [OSTI]

The 32nd International Electric Propulsion Conference, Wiesbaden, Germany September 11 ­ 15, 2011 1 Electric Propulsion Conference, Wiesbaden · Germany September 11 ­ 15, 2011 K. Matyash1 , Max-Planck-Institut für Plasmaphysik, EURATOM Association, Greifswald, D-17491, Germany R. Schneider2 , Greifswald

155

Design and Control of the Induction Motor Propulsion of an Electric Vehicle  

E-Print Network [OSTI]

Design and Control of the Induction Motor Propulsion of an Electric Vehicle B. Tabbache1,2 , A for presizing the induction motor propulsion of an Electric Vehicle (EV). Based on the EV desired performances for different induction motor-based EVs using a siding mode control technique. Index Terms--Electric Vehicle (EV

Brest, Université de

156

An Exoskeleton Using Controlled Energy Storage and Release to Aid Ankle Propulsion  

E-Print Network [OSTI]

An Exoskeleton Using Controlled Energy Storage and Release to Aid Ankle Propulsion M. Bruce Wiggin Mellon University Pittsburgh, PA, USA Abstract -- Symmetric ankle propulsion is the cornerstone of efficient human walking. The ankle plantar flexors provide the majority of the mechanical work for the step

Collins, Steven H.

157

The 33st International Electric Propulsion Conference, The George Washington University, USA October 6 10, 2013  

E-Print Network [OSTI]

The 33st International Electric Propulsion Conference, The George Washington University, USA, 30332, USA Abstract: Accurate measurement of ion charge flux in the plume of spacecraft electric.walker@ae.gatech.edu #12;The 33st International Electric Propulsion Conference, The George Washington University, USA

Walker, Mitchell

158

Magnetic Propulsion of Intense Lithium Streams in a Tokamak Magnetic Field  

E-Print Network [OSTI]

Magnetic Propulsion of Intense Lithium Streams in a Tokamak Magnetic Field Leonid E. Zakharov the theory of magnetic propulsion of liquid lithium streams and their stability in tokamaks and other interactions with the magnetic #12;eld. A criterion is obtained for stabilization of the \\sausage

Zakharov, Leonid E.

159

Design, fabrication and analysis of a body-caudal fin propulsion system for a microrobotic fish  

E-Print Network [OSTI]

Design, fabrication and analysis of a body-caudal fin propulsion system for a microrobotic fish Kyu and fabrica- tion of a centimeter-scale propulsion system for a robotic fish. The key to the design are customized to provide the necessary work output for the microrobotic fish. The flexure joints, electrical

Wood, Robert

160

Definition, Expansion and Screening of Architectures for Planetary Exploration Class Nuclear Electric Propulsion and Power Systems  

E-Print Network [OSTI]

Nuclear Electric Propulsion and Power Systems By Bryan K. Smith Submitted to the System Design, expansion and screening of Nuclear Electric Propulsion and Power concepts capable of achieving planetaryDefinition, Expansion and Screening of Architectures for Planetary Exploration Class Nuclear

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Technology survey and performance scaling for the design of high power nuclear electric power and propulsion systems  

E-Print Network [OSTI]

High power nuclear electric propulsion systems have the capability to enable many next-generation space exploration applications. To date, use of electric primary propulsion in flight systems has been limited to low-power, ...

White, Daniel B., Jr

2011-01-01T23:59:59.000Z

162

Coupling of twin rectangular supersonic jets  

E-Print Network [OSTI]

Twin jet plumes on aircraft can couple, producing dynamic pressures significant enough to cause structural fatigue. For closely spaced jets with a moderate aspect ratio (e.g. 5), previous work has established that two ...

Raman, G.; Taghavi, Ray

1998-01-01T23:59:59.000Z

163

The Georgi Algorithms of Jet Clustering  

E-Print Network [OSTI]

We reveal the direct link between the jet clustering algorithms recently proposed by Howard Georgi and parton shower kinematics, providing sound support from the theoretical side. The kinematics of this class of elegant algorithms is explored systematically and the jet function is generalized to $J^{(n)}_\\beta$ with a jet function index $n$. Based on three basic requirements that the result of jet clustering is process-independent, for softer subjets the inclusion cone is larger, and that the cone size cannot be too large in order to avoid mixing different jets, we derive constraints on the jet function index $n$ and the jet function parameter $\\beta$ which are closely related to phase space boundaries. Finally, we demonstrate that the jet algorithm is boost invariant.

Shao-Feng Ge

2014-08-30T23:59:59.000Z

164

Theoretical and Experimental Simulation of Accident Scenarios of the JET Cryogenic Components Part I: The JET In-vessel Cryopump  

E-Print Network [OSTI]

Theoretical and Experimental Simulation of Accident Scenarios of the JET Cryogenic Components Part I: The JET In-vessel Cryopump

165

Theoretical and Experimental Simulation of Accident Scenarios of the JET Cryogenic Components Part II: The JET LHCD Cryopump  

E-Print Network [OSTI]

Theoretical and Experimental Simulation of Accident Scenarios of the JET Cryogenic Components Part II: The JET LHCD Cryopump

166

Advanced thermally stable jet fuels  

SciTech Connect (OSTI)

The Pennsylvania State University program in advanced thermally stable coal-based jet fuels has five broad objectives: (1) Development of mechanisms of degradation and solids formation; (2) Quantitative measurement of growth of sub-micrometer and micrometer-sized particles suspended in fuels during thermal stressing; (3) Characterization of carbonaceous deposits by various instrumental and microscopic methods; (4) Elucidation of the role of additives in retarding the formation of carbonaceous solids; (5) Assessment of the potential of production of high yields of cycloalkanes by direct liquefaction of coal. Future high-Mach aircraft will place severe thermal demands on jet fuels, requiring the development of novel, hybrid fuel mixtures capable of withstanding temperatures in the range of 400--500 C. In the new aircraft, jet fuel will serve as both an energy source and a heat sink for cooling the airframe, engine, and system components. The ultimate development of such advanced fuels requires a thorough understanding of the thermal decomposition behavior of jet fuels under supercritical conditions. Considering that jet fuels consist of hundreds of compounds, this task must begin with a study of the thermal degradation behavior of select model compounds under supercritical conditions. The research performed by The Pennsylvania State University was focused on five major tasks that reflect the objectives stated above: Task 1: Investigation of the Quantitative Degradation of Fuels; Task 2: Investigation of Incipient Deposition; Task 3: Characterization of Solid Gums, Sediments, and Carbonaceous Deposits; Task 4: Coal-Based Fuel Stabilization Studies; and Task 5: Exploratory Studies on the Direct Conversion of Coal to High Quality Jet Fuels. The major findings of each of these tasks are presented in this executive summary. A description of the sub-tasks performed under each of these tasks and the findings of those studies are provided in the remainder of this volume (Sections 1 through 5).

Schobert, H.H.

1999-01-31T23:59:59.000Z

167

Jet physics at HERA, Tevatron and LHC  

E-Print Network [OSTI]

In this short report, we discuss the Jet Physics results and perspectives at HERA, Tevatron and LHC.

C. Royon

2008-11-10T23:59:59.000Z

168

Inclusive jet production at the Tevatron  

SciTech Connect (OSTI)

Preliminary results on inclusive jet production in proton-antiproton collisions at {radical}s = 1.96 TeV based on 1 fb{sup -1} of CDF Run II data are presented. Measurements are preformed using different jet algorithms in a wide range of jet transverse momentum and jet rapidity. The measured cross sections are compared to next-to-leading order perturbative QCD calculations

Norniella, Olga; /Barcelona, IFAE

2006-08-01T23:59:59.000Z

169

Monte Carlo Tools for Jet Quenching  

E-Print Network [OSTI]

A thorough understanding of jet quenching on the basis of multi-particle final states and jet observables requires new theoretical tools. This talk summarises the status and propects of the theoretical description of jet quenching in terms of Monte Carlo generators.

Korinna Zapp

2011-09-07T23:59:59.000Z

170

Heavy Vehicle Propulsion Materials: Recent Progress and Future Plans  

SciTech Connect (OSTI)

The Heavy Vehicle Propulsion Materials Program provides enabling materials technology for the U.S. DOE Office of Heavy Vehicle Technologies (OHVT). The technical agenda for the program is based on an industry assessment and the technology roadmap for the OHVT. A five-year program plan was published in 2000. Major efforts in the program are materials for diesel engine fuel systems, exhaust aftertreatment, and air handling. Additional efforts include diesel engine valve-train materials, structural components, and thermal management. Advanced materials, including high-temperature metal alloys, intermetallics, cermets, ceramics, amorphous materials, metal- and ceramic-matrix composites, and coatings, are investigated for critical engine applications. Selected technical issues and planned and ongoing projects as well as brief summaries of several technical highlights are given.

D. Ray Johnson; Sidney Diamond

2001-05-14T23:59:59.000Z

171

Nuclear space power and propulsion requirements and issues  

SciTech Connect (OSTI)

The use of nuclear power in space is going through a low point. The kinds of missions that would use nuclear power are expensive and there are few new expensive missions. Both NASA and DoD are in a mode of cheaper, faster, better, which means using what is available as much as possible and only incorporating new technology to reduce mission cost. NASA is performing Mission to Planet Earth and detailed exploration missions of Mars. These NASA missions can be done with solar-battery power subsystems and there is no need for nuclear power. The NASA mission to Pluto does require nuclear radioisotope power. Ways to reduce the power subsystem cost and the power level are being investigated. NASA is studying ways to explore beyond Mars with solar-battery power because of the cost and uncertainty in the availability and launchability of nuclear space power systems. The DoD missions are all in earth orbit and can be done with solar-battery systems. The major DoD requirement at present is to reduce costs of all their space missions. One way to do this is to develop highly efficient upper stage boosters that can be integrated with lower cost Earth to low orbit stages and still place their payloads in to higher orbits. One attractive upper stage is a nuclear bimodal (propulsion and power) engine to accomplished lower booster cost to place space assets in GEO. However this is not being pursued because of DOE`s new policy not to fund nuclear space power research and development as well as the difficulty in obtaining launch approval for nuclear propulsion and power systems.

Swerdling, M. [IR Associates, North Hills, CA (United States); Isenberg, L. [IR Associates, La Habra, CA (United States)

1995-12-31T23:59:59.000Z

172

Photoproduction of jets at NLO  

E-Print Network [OSTI]

A new next-to-leading order Monte Carlo program for the calculation of fully differential jet cross sections in photoproduction is described. The contributions from both resolved and direct components are included. A comparison between the theoretical predictions and ZEUS data is presented.

B. W. Harris; J. F. Owens

1996-08-20T23:59:59.000Z

173

The Disc-Jet Connection  

E-Print Network [OSTI]

A large body of theoretical and computational work shows that jets - modelled as magnetized disk winds - exert an external torque on their underlying disks that can efficiently remove angular momentum and act as major drivers of disk accretion. These predictions have recently been confirmed in direct HST measurements of the jet rotation and angular momentum transport in low mass protostellar systems. We review the theory of disc winds and show that their physics is universal and scales to jets from both low and high mass star forming regions. This explains the observed properties of outflows in massive star forming regions, before the central massive star generates an ultracompact HII region. We also discuss the recent numerical studies on the formation of massive accretion disks and outflows through gravitational collapse, including our own work on 3D Adaptive Mesh simulations (using the FLASH code) of the hydromagnetic collapse of an initial rotating, and cooling Bonner-Ebert sphere. Magnetized collapse gives rise to outflows. Our own simulations show that both a jet-like disk wind on sub AU scales, and a larger scale molecular outflow occur (Banerjee and Pudritz 2005).

Ralph E. Pudritz; Robi Banerjee

2005-07-11T23:59:59.000Z

174

Laser Created Relativistic Positron Jets  

SciTech Connect (OSTI)

Electron-positron jets with MeV temperature are thought to be present in a wide variety of astrophysical phenomena such as active galaxies, quasars, gamma ray bursts and black holes. They have now been created in the laboratory in a controlled fashion by irradiating a gold target with an intense picosecond duration laser pulse. About 10{sup 11} MeV positrons are emitted from the rear surface of the target in a 15 to 22-degree cone for a duration comparable to the laser pulse. These positron jets are quasi-monoenergetic (E/{delta}E {approx} 5) with peak energies controllable from 3-19 MeV. They have temperatures from 1-4 MeV in the beam frame in both the longitudinal and transverse directions. Positron production has been studied extensively in recent decades at low energies (sub-MeV) in areas related to surface science, positron emission tomography, basic antimatter science such as antihydrogen experiments, Bose-Einstein condensed positronium, and basic plasma physics. However, the experimental tools to produce very high temperature positrons and high-flux positron jets needed to simulate astrophysical positron conditions have so far been absent. The MeV temperature jets of positrons and electrons produced in our experiments offer a first step to evaluate the physics models used to explain some of the most energetic phenomena in the universe.

Chen, H; Wilks, S C; Meyerhofer, D D; Bonlie, J; Chen, C D; Chen, S N; Courtois, C; Elberson, L; Gregori, G; Kruer, W; Landoas, O; Mithen, J; Murphy, C; Nilson, P; Price, D; Scheider, M; Shepherd, R; Stoeckl, C; Tabak, M; Tommasini, R; Beiersdorder, P

2009-10-08T23:59:59.000Z

175

Jet energy scale setting with "photon+Jet" events at LHC energies. Selection of events with a clean "photon+Jet" topology and photon Pt - jet Pt disbalance  

E-Print Network [OSTI]

It is shown in the paper that Pt activity limitation (modulus of the vector sum) of all particle beyond "photon+Jet" system Pt^out leads to the noticeable photon Pt - jet Pt disbalance decreasing. On a simultaneous restriction of the cluster Pt and Pt^out from above it is possible to reach an acceptable balance between photon Pt - jet Pt with a sufficient number of the photon Pt - jet Pt events for the jet energy scale setting and hadron calorimeter calibratiom of the CMS detector at LHC.

D. V. Bandourin; V. F. Konoplyanikov; N. B. Skachkov

2001-04-27T23:59:59.000Z

176

Radioisotope electric propulsion of sciencecraft to the outer solar system and near-interstellar space  

SciTech Connect (OSTI)

Recent results are presented in the study of radioisotope electric propulsion as a near-term technology for sending small robotic sciencecraft to the outer Solar System and near-interstellar space. Radioisotope electric propulsion (REP) systems are low-thrust, ion propulsion units based on radioisotope electric generators and ion thrusters. Powerplant specific masses are expected to be in the range of 100 to 200 kg/kW of thrust power. Planetary rendezvous missions to Pluto, fast missions to the heliopause (100 AU) with the capability to decelerate an orbiter for an extended science program and prestellar missions to the first gravitational lens focus of the Sun (550 AU) are investigated.

Noble, R.J.

1998-08-01T23:59:59.000Z

177

Synthetic jets at large Reynolds number and comparison to continuous jets  

SciTech Connect (OSTI)

Experimental measurements and flow visualization of synthetic jets and similar continuous jets are described. The dimensionless stroke length necessary to form a 2-D synthetic jet is between 5 and 10, with wider-nozzle jets consistently requiring a smaller value. Synthetic jets are wider, slower and have more momentum than similar continuous jets. Synthetic jets are generated using four nozzle widths that vary by a factor of four, and the driving frequency is varied over an order of magnitude. The resultant jets are in the range 13.5 < L{sub o}/h < 80.8 and 695 < Re{sub Uo} < 14700. In spite of the large range of stroke lengths, the near-field behavior of the synthetic jets scales with L{sub o}/h.

Smith, B. L. (Barton L.); Swift, G. W. (Gregory W.)

2001-01-01T23:59:59.000Z

178

An impulse framework for hydrodynamic force analysis : fish propulsion, water entry of spheres, and marine propellers  

E-Print Network [OSTI]

This thesis presents an impulse framework for analyzing the hydrodynamic forces on bodies in flow. This general theoretical framework is widely applicable, and it is used to address the hydrodynamics of fish propulsion, ...

Epps, Brenden P

2010-01-01T23:59:59.000Z

179

Submarine propulsion shaft life : probabilistic prediction and extension through prevention of water ingress  

E-Print Network [OSTI]

Submarine propulsion shafts have demonstrated acceptable reliability performance when inspected and refurbished at least every 6 years. Designers wish to extend the inspection interval to 12 years without sacrificing ...

Jonart, Douglas E. (Douglas Edward)

2014-01-01T23:59:59.000Z

180

A fully microfabricated two-dimensional electrospray array with applications to space propulsion  

E-Print Network [OSTI]

This thesis presents the design, fabrication and testing of a fully-integrated planar electrospray thruster array, which could lead to more efficient and precise thrusters for space propulsion applications. The same ...

Gassend, Blaise L. P. (Blaise Laurent Patrick), 1978-

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Innovative nuclear thermal propulsion technology evaluation: Results of the NASA/DOE Task Team study  

SciTech Connect (OSTI)

In response to findings from two NASA/DOE nuclear propulsion workshops held in the summer of 1990, six task teams were formed to continue evaluation of various nuclear propulsion concepts. The Task Team on Nuclear Thermal Propulsion (NTP) created the Innovative Concepts Subpanel to evaluate thermal propulsion concepts which did not utilize solid fuel. The Subpanel endeavored to evaluate each of the concepts on a level technological playing field,'' and to identify critical technologies, issues, and early proof-of-concept experiments. The concepts included the liquid core fission, the gas core fission, the fission foil reactors, explosively driven systems, fusion, and antimatter. The results of the studies by the panel will be provided. 13 refs., 6 figs., 2 tabs.

Howe, S. (Los Alamos National Lab., NM (United States)); Borowski, S. (National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center); Motloch, C. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Helms, I. (Nuclear Utility Services, Damascus, MD (United States)); Diaz, N.; Anghaie, S. (Florida Univ., Gainesville, FL (United States)); Latham, T. (United

1991-01-01T23:59:59.000Z

182

Thermal-hydraulics Analysis of a Radioisotope-powered Mars Hopper Propulsion System  

SciTech Connect (OSTI)

Thermal-hydraulics analyses results produced using a combined suite of computational design and analysis codes are presented for the preliminary design of a concept Radioisotope Thermal Rocket (RTR) propulsion system. Modeling of the transient heating and steady state temperatures of the system is presented. Simulation results for propellant blow down during impulsive operation are also presented. The results from this study validate the feasibility of a practical thermally capacitive RTR propulsion system.

Robert C. O'Brien; Andrew C. Klein; William T. Taitano; Justice Gibson; Brian Myers; Steven D. Howe

2011-02-01T23:59:59.000Z

183

Heavy vehicle hybrid propulsion systems R and D program plan, FY 2000-2005  

SciTech Connect (OSTI)

This report contains the program plan and background information for the Heavy Vehicle Hybrid Propulsion R and D Program sponsored by the Department of Energy's Office of Heavy Vehicle Technologies. The program is a collaboration between industry and government established for the development of advanced hybrid-electric propulsion technology for urban cycle trucks and buses. It targets specific applications to enhance potential market success. Potential end-users are also involved.

None

2000-07-01T23:59:59.000Z

184

Numerical Simulations of Bouncing Jets  

E-Print Network [OSTI]

downhill gliding of the pool, at about 4mm/s of pool surface velocity. . . . . . . . . . . . . . . . . . . . . . 87 viii 5.7 Overall view of the shampoo jet bouncing of an inclined pool of the same liquid. The white arrow points at he breakup of the air....4 Time discretization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 3.5 Entropy residual stabilization . . . . . . . . . . . . . . . . . . . . . . 58 3.6 Adaptive mesh refinement . . . . . . . . . . . . . . . . . . . . . . . . 61 iv 3.7...

Lee, Sanghyun

2014-07-18T23:59:59.000Z

185

Fluid jet electric discharge source  

DOE Patents [OSTI]

A fluid jet or filament source and a pair of coaxial high voltage electrodes, in combination, comprise an electrical discharge system to produce radiation and, in particular, EUV radiation. The fluid jet source is composed of at least two serially connected reservoirs, a first reservoir into which a fluid, that can be either a liquid or a gas, can be fed at some pressure higher than atmospheric and a second reservoir maintained at a lower pressure than the first. The fluid is allowed to expand through an aperture into a high vacuum region between a pair of coaxial electrodes. This second expansion produces a narrow well-directed fluid jet whose size is dependent on the size and configuration of the apertures and the pressure used in the reservoir. At some time during the flow of the fluid filament, a high voltage pulse is applied to the electrodes to excite the fluid to form a plasma which provides the desired radiation; the wavelength of the radiation being determined by the composition of the fluid.

Bender, Howard A. (Ripon, CA)

2006-04-25T23:59:59.000Z

186

Radioisotope electric propulsion for robotic science missions to near-interstellar space  

SciTech Connect (OSTI)

The use of radioisotope electric propulsion for sending small robotic probes on fast science missions several hundred astronomical units (AU) from the Sun is investigated. Such missions would address a large variety of solar, interstellar, galactic and cosmological science themes from unique vantage points at 100 to 600 AU, including parallax distance measurements for the entire Milky Way Galaxy, sampling of the interstellar medium and imaging of cosmological objects at the gravitational lens foci of the Sun ({ge} 550 AU). Radioisotope electric propulsion (REP) systems are low-thrust, ion propulsion units based on multi-hundred watt, radioisotope electric generators and ion thrusters. In a previous work, the flight times for rendezvous missions to the outer planets (< 30 AU) using REP were found to be less than fifteen years. However fast prestellar missions to several hundred AU are not possible unless the probe`s energy can be substantially increased in the inner Solar System so as to boost the final hyperbolic excess velocity. In this paper an economical hybrid propulsion scheme combining chemical propulsion and gravity assist in the inner Solar System and radioisotope electric propulsion in the outer Solar System is studied which enables fast prestellar missions. Total hyperbolic excess velocities of 15 AU/year and flight times to 550 AU of about 40 years are possible using REP technology that may be available in the next decade.

Noble, R.J.

1994-10-01T23:59:59.000Z

187

RSMASS-D nuclear thermal propulsion and bimodal system mass models  

SciTech Connect (OSTI)

Two relatively simple models have been developed to estimate reactor, radiation shield, and balance of system masses for a particle bed reactor (PBR) nuclear thermal propulsion concept and a cermet-core power and propulsion (bimodal) concept. The approach was based on the methodology developed for the RSMASS-D models. The RSMASS-D approach for the reactor and shield sub-systems uses a combination of simple equations derived from reactor physics and other fundamental considerations along with tabulations of data from more detailed neutron and gamma transport theory computations. Relatively simple models are used to estimate the masses of other subsystem components of the nuclear propulsion and bimodal systems. Other subsystem components include instrumentation and control (I&C), boom, safety systems, radiator, thermoelectrics, heat pipes, and nozzle. The user of these models can vary basic design parameters within an allowed range to achieve a parameter choice which yields a minimum mass for the operational conditions of interest. Estimated system masses are presented for a range of reactor power levels for propulsion for the PBR propulsion concept and for both electrical power and propulsion for the cermet-core bimodal concept. The estimated reactor system masses agree with mass predictions from detailed calculations with xx percent for both models. {copyright} {ital 1997 American Institute of Physics.}

King, D.B. [DSWA/FC, Thermionic Evaluation Facility 801 University Blvd. SE Albuquerque, New Mexico (United States); Marshall, A.C. [DSWA/FC, Thermionic Evaluation Facility 801 University Blvd. SE Albuquerque, New Mexico (United States)

1997-01-01T23:59:59.000Z

188

RSMASS-D nuclear thermal propulsion and bimodal system mass models  

SciTech Connect (OSTI)

Two relatively simple models have been developed to estimate reactor, radiation shield, and balance of system masses for a particle bed reactor (PBR) nuclear thermal propulsion concept and a cermet-core power and propulsion (bimodal) concept. The approach was based on the methodology developed for the RSMASS-D models. The RSMASS-D approach for the reactor and shield sub-systems uses a combination of simple equations derived from reactor physics and other fundamental considerations along with tabulations of data from more detailed neutron and gamma transport theory computations. Relatively simple models are used to estimate the masses of other subsystem components of the nuclear propulsion and bimodal systems. Other subsystem components include instrumentation and control (I and C), boom, safety systems, radiator, thermoelectrics, heat pipes, and nozzle. The user of these models can vary basic design parameters within an allowed range to achieve a parameter choice which yields a minimum mass for the operational conditions of interest. Estimated system masses are presented for a range of reactor power levels for propulsion for the PBR propulsion concept and for both electrical power and propulsion for the cermet-core bimodal concept. The estimated reactor system masses agree with mass predictions from detailed calculations with xx percent for both models.

King, Donald B.; Marshall, Albert C. [DSWA/FC, Thermionic Evaluation Facility 801 University Blvd. SE Albuquerque, New Mexico (United States); DSWA/FC, Thermionic Evaluation Facility 801 University Blvd. SE Albuquerque, New Mexico (United States)

1997-01-10T23:59:59.000Z

189

Turbulent fluid jet excavation in cohesive soil : with particular application to jet grouting  

E-Print Network [OSTI]

This thesis reviews the jet grouting methodology, and the current state of practice and research. Current methods of prediction of jet grout diameters are highly empirical and site specific, and do not take into account ...

Ho, Chu Eu

2005-01-01T23:59:59.000Z

190

Combining Resummed Higgs Predictions Across Jet Bins  

E-Print Network [OSTI]

Experimental analyses often use jet binning to distinguish between different kinematic regimes and separate contributions from background processes. To accurately model theoretical uncertainties in these measurements, a consistent description of the jet bins is required. We present a complete framework for the combination of resummed results for production processes in different exclusive jet bins, focusing on Higgs production in gluon fusion as an example. We extend the resummation of the Higgs + 1-jet cross section into the challenging low transverse momentum region, lowering the uncertainties considerably. We provide combined predictions with resummation for cross sections in the Higgs + 0-jet and Higgs + 1-jet bins, and give an improved theory covariance matrix for use in experimental studies. We estimate that the relevant theoretical uncertainties on the signal strength in the Higgs to WW analysis are reduced by nearly a factor of 2 compared to the current value.

Radja Boughezal; Xiaohui Liu; Frank Petriello; Frank J. Tackmann; Jonathan R. Walsh

2013-12-16T23:59:59.000Z

191

Advanced Fusion Reactors for Space Propulsion and Power Systems  

SciTech Connect (OSTI)

In recent years the methodology proposed for conversion of light elements into energy via fusion has made steady progress. Scientific studies and engineering efforts in advanced fusion systems designs have introduced some new concepts with unique aspects including consideration of Aneutronic fuels. The plant parameters for harnessing aneutronic fusion appear more exigent than those required for the conventional fusion fuel cycle. However aneutronic fusion propulsion plants for Space deployment will ultimately offer the possibility of enhanced performance from nuclear gain as compared to existing ionic engines as well as providing a clean solution to Planetary Protection considerations and requirements. Proton triggered 11Boron fuel (p- 11B) will produce abundant ion kinetic energy for In-Space vectored thrust. Thus energetic alpha particles' exhaust momentum can be used directly to produce high Isp thrust and also offer possibility of power conversion into electricity. p-11B is an advanced fusion plant fuel with well understood reaction kinematics but will require some new conceptual thinking as to the most effective implementation.

Chapman, John J.

2011-06-15T23:59:59.000Z

192

A tandem mirror hybrid plume plasma propulsion facility  

SciTech Connect (OSTI)

A concept in electrodeless plasma propulsion, which is also capable of delivering a variable Isp, is presented. The concept involves a three-stage system of plasma injection, heating, and subsequent ejection through a magnetic nozzle. The nozzle produces the hybrid plume by the coaxial injection of hypersonic neutral gas. The gas layer, thus formed, protects the material walls from the hot plasma and, through increased collisions, helps detach it from the diverging magnetic field. The physics of this concept is evaluated numerically through full spatial and temporal simulations; these explore the operating characteristics of such a device over a wide region of parameter space. An experimental facility to study the plasma dynamics in the hybrid plume was built. The device consists of a tandem mirror operating in an asymmetric mode. A later upgrade of this system will incorporate a cold plasma injector at one end of the machine. Initial experiments involve the full characterization of the operating envelope, as well as extensive measurements of plasma properties at the exhaust. The results of the numerical simulations are described.

Chang-Diaz, F.R.; Yang, T.F.; Krueger, W.A.; Peng, S.; Urbahn, J.; Yao, X.; Griffin, D.

1988-01-01T23:59:59.000Z

193

LDV Measurement of Confined Parallel Jet Mixing  

SciTech Connect (OSTI)

Laser Doppler Velocimetry (LDV) measurements were taken in a confinement, bounded by two parallel walls, into which issues a row of parallel jets. Two-component measurements were taken of two mean velocity components and three Reynolds stress components. As observed in isolated three dimensional wall bounded jets, the transverse diffusion of the jets is quite large. The data indicate that this rapid mixing process is due to strong secondary flows, transport of large inlet intensities and Reynolds stress anisotropy effects.

R.F. Kunz; S.W. D'Amico; P.F. Vassallo; M.A. Zaccaria

2001-01-31T23:59:59.000Z

194

Jet physics in Run 2 at CDF  

SciTech Connect (OSTI)

New CDF Run 2 results on the inclusive jet cross section (K{sub T} algorithm) and the b-jet cross section (MidPoint algorithm) are presented and compared with theory. We also study the ''underlying event'' by using the direction of the leading jet to isolate regions of {eta}-{phi} space that are very sensitive to the ''beam-beam'' remnants and to multiple parton interactions.

Field, R.; /Florida U.

2005-01-01T23:59:59.000Z

195

Nuclear Composition of Magnetized GRB Jets  

E-Print Network [OSTI]

We investigate the fraction of metal nuclei in the relativistic jets of gamma-ray bursts associated with core-collapse supernovae. We simulate the fallback in jet-induced explosions with two-dimensional relativistic hydrodynamics calculations and the jet acceleration with steady, radial, relativistic magnetohydrodynamics calculations, and derive detail nuclear composition of the jet by postprocessing calculation. We found that if the temperature at the jet launch site is above $4.7\\times 10^9$K, quasi-statistical equilibrium (QSE) is established and heavy nuclei are dissociated to light particles such as $^4$He during the acceleration of the jets. The criterion for the survival of metal nuclei is written in terms of the isotropic jet luminosity as $L_{\\rm j}^{\\rm iso} \\lesssim 3.9\\times 10^{50}(R_{\\rm i}/10^7{\\rm cm})^2 (1+\\sigma_{\\rm i})~{\\rm erg~s^{-1}}$, where $R_{\\rm i}$ and $\\sigma_{\\rm i}$ are the initial radius of the jets and the initial magnetization parameter, respectively. If the jet is initially d...

Shibata, Sanshiro

2015-01-01T23:59:59.000Z

196

PHYSICAL PARAMETERS OF STANDARD AND BLOWOUT JETS  

SciTech Connect (OSTI)

The X-ray Telescope on board the Hinode mission revealed the occurrence, in polar coronal holes, of much more numerous jets than previously indicated by the Yohkoh/Soft X-ray Telescope. These plasma ejections can be of two types, depending on whether they fit the standard reconnection scenario for coronal jets or if they include a blowout-like eruption. In this work, we analyze two jets, one standard and one blowout, that have been observed by the Hinode and STEREO experiments. We aim to infer differences in the physical parameters that correspond to the different morphologies of the events. To this end, we adopt spectroscopic techniques and determine the profiles of the plasma temperature, density, and outflow speed versus time and position along the jets. The blowout jet has a higher outflow speed, a marginally higher temperature, and is rooted in a stronger magnetic field region than the standard event. Our data provide evidence for recursively occurring reconnection episodes within both the standard and the blowout jet, pointing either to bursty reconnection or to reconnection occurring at different locations over the jet lifetimes. We make a crude estimate of the energy budget of the two jets and show how energy is partitioned among different forms. Also, we show that the magnetic energy that feeds the blowout jet is a factor of 10 higher than the magnetic energy that fuels the standard event.

Pucci, Stefano; Romoli, Marco [Department of Physics and Astronomy, University of Firenze, I-50121 Firenze (Italy); Poletto, Giannina [INAF-Arcetri Astrophysical Observatory, I-50125 Firenze (Italy); Sterling, Alphonse C., E-mail: stpucci@arcetri.astro.it [Space Science Office, NASA/MSFC, Huntsville, Al 35812 (United States)

2013-10-10T23:59:59.000Z

197

Drying characteristics of slot jet reattachment nozzle and comparison with a slot jet nozzle  

E-Print Network [OSTI]

the same flow power and flow exerted surface peak pressure. The same flow power results showed that +45[] and +20[] SJR nozzles performed better than the slot jet nozzle, while the 0[] SJR had drying characteristics similar to the slot jet. The slot jet...

Alam, Syed Aftab

2012-06-07T23:59:59.000Z

198

Space variations in axis height of the jet stream core  

E-Print Network [OSTI]

height of the jet axis relative to the height of the jet maximum for slow vs. fast cases. 13 Mean height of the jet axis relative to the height at the trough. 13 Mean height of the jet axis relative to the height at the ridge. 15 Mean height... of the jet axis relative to the height at the jet maximum, when the maximum is near a trough. 15 Mean height of the jet axis relative to the height at the minimum, when the minimum is near a ridge. 17 Mean height of the jet axis relative to the height...

Leutwyler, Cooke Hearon

1965-01-01T23:59:59.000Z

199

Why Do Disks Form Jets?  

E-Print Network [OSTI]

It is argued that jet modelers have given insufficient study to the natural magneto-static configurations of field wound up in the presence of a confining general pressure. Such fields form towers whose height grows with each twist at a velocity comparable to the circular velocity of the accretion disk that turns them. A discussion of the generation of such towers is preceded by a brief history of the idea that quasars, active galaxies, and galactic nuclei contain giant black holes with accretion disks.

D Lynden-Bell

2002-03-27T23:59:59.000Z

200

A New Capability for Nuclear Thermal Propulsion Design  

SciTech Connect (OSTI)

This paper describes a new capability for Nuclear Thermal Propulsion (NTP) design that has been developed, and presents the results of some analyses performed with this design tool. The purpose of the tool is to design to specified mission and material limits, while maximizing system thrust to weight. The head end of the design tool utilizes the ROCket Engine Transient Simulation (ROCETS) code to generate a system design and system design requirements as inputs to the core analysis. ROCETS is a modular system level code which has been used extensively in the liquid rocket engine industry for many years. The core design tool performs high-fidelity reactor core nuclear and thermal-hydraulic design analysis. At the heart of this process are two codes TMSS-NTP and NTPgen, which together greatly automate the analysis, providing the capability to rapidly produce designs that meet all specified requirements while minimizing mass. A PERL based command script, called CORE DESIGNER controls the execution of these two codes, and checks for convergence throughout the process. TMSS-NTP is executed first, to produce a suite of core designs that meet the specified reactor core mechanical, thermal-hydraulic and structural requirements. The suite of designs consists of a set of core layouts and, for each core layout specific designs that span a range of core fuel volumes. NTPgen generates MCNPX models for each of the core designs from TMSS-NTP. Iterative analyses are performed in NTPgen until a reactor design (fuel volume) is identified for each core layout that meets cold and hot operation reactivity requirements and that is zoned to meet a radial core power distribution requirement.

Amiri, Benjamin W. [Nuclear Systems Design Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Nuclear and Radiological Engineering Department, University of Florida, Gainesville, FL 32611 (United States); Kapernick, Richard J. [Nuclear Systems Design Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Sims, Bryan T. [Nuclear Systems Design Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); School of Nuclear Engineering, Purdue University, West Lafayette, IN 47907 (United States); Simpson, Steven P. [NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States)

2007-01-30T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Miniconference on astrophysical jets P. M. Bellan  

E-Print Network [OSTI]

and numerical modelers of both astrophysical jets and spheromaks, and laboratory experimentalists. The purpose-organization. Spheromaks have been studied for the last two decades and most recently, it has been realized that the physics of spheromak formation has much in common with magnetohydrodynamically driven astrophysical jets

Bellan, Paul M.

202

Jet multiplicities as the QGP thermometer  

E-Print Network [OSTI]

It is proposed to use the energy behavior of mean multiplicities of jets propagating in a nuclear medium as the thermometer of this medium during the collision phases. The qualitative effects are demonstrated in the framework of the fixed coupling QCD with account of jet quenching.

I. M. Dremin; O. S. Shadrin

2006-02-10T23:59:59.000Z

203

$W/Z$ + jets results from CDF  

SciTech Connect (OSTI)

The CDF Collaboration has a comprehensive program of studying the production of vector bosons, W and Z, in association with energetic jets. Excellent understanding of the standard model W/Z+jets and W/Z+c,b-jets processes is of paramount importance for the top quark physics and for the Higgs boson and many new physics searches. We review the latest CDF results on Z-boson production in association with inclusive and b-quark jets, study of the p{sub T} balance in Z+jet events, and a measurement of the W+charm production cross section. The results are based on 4-5 fb{sup -1} of data and compared to various Monte Carlo and next-to-leading order perturbative QCD predictions.

Camarda, Stefano; /Barcelona, IFAE

2010-01-01T23:59:59.000Z

204

Atmospheric-pressure plasma jet  

DOE Patents [OSTI]

Atmospheric-pressure plasma jet. A .gamma.-mode, resonant-cavity plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two concentric cylindrical electrodes are employed to generate a plasma in the annular region therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly shaping the rf-powered electrode. Because of the atmospheric pressure operation, no ions survive for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike low-pressure plasma sources and conventional plasma processing methods.

Selwyn, Gary S. (Los Alamos, NM)

1999-01-01T23:59:59.000Z

205

Can Protostellar Jets Drive Supersonic Turbulence in Molecular Clouds?  

E-Print Network [OSTI]

Jets and outflows from young stellar objects are proposed candidates to drive supersonic turbulence in molecular clouds. Here, we present the results from multi-dimensional jet simulations where we investigate in detail the energy and momentum deposition from jets into their surrounding environment and quantify the character of the excited turbulence with velocity probability density functions. Our study include jet--clump interaction, transient jets, and magnetised jets. We find that collimated supersonic jets do not excite supersonic motions far from the vicinity of the jet. Supersonic fluctuations are damped quickly and do not spread into the parent cloud. Instead subsonic, non-compressional modes occupy most of the excited volume. This is a generic feature which can not be fully circumvented by overdense jets or magnetic fields. Nevertheless, jets are able to leave strong imprints in their cloud structure and can disrupt dense clumps. Our results question the ability of collimated jets to sustain supersonic turbulence in molecular clouds.

Robi Banerjee; Ralf S. Klessen; Christian Fendt

2007-06-25T23:59:59.000Z

206

An inkjet vision measurement technique for high-frequency jetting  

SciTech Connect (OSTI)

Inkjet technology has been used as manufacturing a tool for printed electronics. To increase the productivity, the jetting frequency needs to be increased. When using high-frequency jetting, the printed pattern quality could be non-uniform since the jetting performance characteristics including the jetting speed and droplet volume could vary significantly with increases in jet frequency. Therefore, high-frequency jetting behavior must be evaluated properly for improvement. However, it is difficult to measure high-frequency jetting behavior using previous vision analysis methods, because subsequent droplets are close or even merged. In this paper, we present vision measurement techniques to evaluate the drop formation of high-frequency jetting. The proposed method is based on tracking target droplets such that subsequent droplets can be excluded in the image analysis by focusing on the target droplet. Finally, a frequency sweeping method for jetting speed and droplet volume is presented to understand the overall jetting frequency effects on jetting performance.

Kwon, Kye-Si, E-mail: kskwon@sch.ac.kr; Jang, Min-Hyuck; Park, Ha Yeong [Department of Mechanical Engineering, Soonchunhyang University 22, Soonchunhyang-Ro, Shinchang, Asan Chungnam 336-745 (Korea, Republic of); Ko, Hyun-Seok [Department of Electrical and Robot Engineering, Soonchunhyang University, 22, Soonchunhyang-Ro, Shinchang, Asan Chungnam 336-745 (Korea, Republic of)

2014-06-15T23:59:59.000Z

207

NSPWG-recommended safety requirements and guidelines for SEI nuclear propulsion  

SciTech Connect (OSTI)

An interagency Nuclear Safety Policy Working Group (NSPWG) was chartered to recommend nuclear safety policy, requirements, and guidelines for the Space Exploration Initiative (SEI) nuclear propulsion program to facilitate the implementation of mission planning and conceptual design studies. The NSPWG developed a top-level policy to provide the guiding principles for the development and implementation of the nuclear propulsion safety program and the development of safety functional requirements. In addition, the NSPWG reviewed safety issues for nuclear propulsion and recommended top-level safety requirements and guidelines to address these issues. Safety requirements were developed for reactor start-up, inadvertent criticality, radiological release and exposure, disposal, entry, and safeguards. Guidelines were recommended for risk/reliability, operational safety, flight trajectory and mission abort, space debris and meteoroids, and ground test safety. In this paper the specific requirements and guidelines will be discussed. 9 refs.

Marshall, A.C.; Sawyer, J.C. Jr.; Bari, R.A.; Brown, N.W.; Cullingford, H.S.; Hardy, A.C.; Lee, J.H.; Mcculloch, W.H.; Niederauer, G.F.; Remp, K. (Sandia National Laboratories, Albuquerque, NM (United States) NASA, Washington (United States) Brookhaven National Laboratory, Upton, NY (United States) General Electric Co., San Jose, CA (United States) NASA, Johnson Space Center, Houston, Tn (United States) L

1992-07-01T23:59:59.000Z

208

NSPWG-recommended safety requirements and guidelines for SEI nuclear propulsion  

SciTech Connect (OSTI)

An Interagency Nuclear Safety Policy Working Group (NSPWG) was chartered to recommend nuclear safety policy, requirements, and guidelines for the Space Exploration Initiative (SEI) nuclear propulsion program to facilitate the implementation of mission planning and conceptual design studies. The NSPWG developed a top- level policy to provide the guiding principles for the development and implementation of the nuclear propulsion safety program and the development of Safety Functional Requirements. In addition the NSPWG reviewed safety issues for nuclear propulsion and recommended top-level safety requirements and guidelines to address these issues. Safety requirements were developed for reactor start-up, inadvertent criticality, radiological release and exposure, disposal, entry, and safeguards. Guidelines were recommended for risk/reliability, operational safety, flight trajectory and mission abort, space debris and meteoroids, and ground test safety. In this paper the specific requirements and guidelines will be discussed.

Marshall, A.C.; Lee, J.H.; McCulloch, W.H. (Sandia National Labs., Albuquerque, NM (United States)); Sawyer, J.C. Jr. (National Aeronautics and Space Administration, Washington, DC (United States)); Bari, R.A. (Brookhaven National Lab., Upton, NY (United States)); Brown, N.W. (General Electric Co., San Jose, CA (United States)); Cullingford, H.S.; Hardy, A.C. (National Aeronautics and Space Administ

1992-01-01T23:59:59.000Z

209

NSPWG-recommended safety requirements and guidelines for SEI nuclear propulsion  

SciTech Connect (OSTI)

An Interagency Nuclear Safety Policy Working Group (NSPWG) was chartered to recommend nuclear safety policy, requirements, and guidelines for the Space Exploration Initiative (SEI) nuclear propulsion program to facilitate the implementation of mission planning and conceptual design studies. The NSPWG developed a top- level policy to provide the guiding principles for the development and implementation of the nuclear propulsion safety program and the development of Safety Functional Requirements. In addition the NSPWG reviewed safety issues for nuclear propulsion and recommended top-level safety requirements and guidelines to address these issues. Safety requirements were developed for reactor start-up, inadvertent criticality, radiological release and exposure, disposal, entry, and safeguards. Guidelines were recommended for risk/reliability, operational safety, flight trajectory and mission abort, space debris and meteoroids, and ground test safety. In this paper the specific requirements and guidelines will be discussed.

Marshall, A.C.; Lee, J.H.; McCulloch, W.H. [Sandia National Labs., Albuquerque, NM (United States); Sawyer, J.C. Jr. [National Aeronautics and Space Administration, Washington, DC (United States); Bari, R.A. [Brookhaven National Lab., Upton, NY (United States); Brown, N.W. [General Electric Co., San Jose, CA (United States); Cullingford, H.S.; Hardy, A.C. [National Aeronautics and Space Administration, Houston, TX (United States). Lyndon B. Johnson Space Center; Niederauer, G.F. [Los Alamos National Lab., NM (United States); Remp, K. [National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center; Rice, J.W. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Sholtis, J.A. [Department of the Air Force, Kirtland AFB, NM (United States)

1992-09-01T23:59:59.000Z

210

Experimental studies of unbiased gluon jets from $e^{+}e^{-}$ annihilations using the jet boost algorithm  

E-Print Network [OSTI]

We present the first experimental results based on the jet boost algorithm, a technique to select unbiased samples of gluon jets in e+e- annihilations, i.e. gluon jets free of biases introduced by event selection or jet finding criteria. Our results are derived from hadronic Z0 decays observed with the OPAL detector at the LEP e+e- collider at CERN. First, we test the boost algorithm through studies with Herwig Monte Carlo events and find that it provides accurate measurements of the charged particle multiplicity distributions of unbiased gluon jets for jet energies larger than about 5 GeV, and of the jet particle energy spectra (fragmentation functions) for jet energies larger than about 14 GeV. Second, we apply the boost algorithm to our data to derive unbiased measurements of the gluon jet multiplicity distribution for energies between about 5 and 18 GeV, and of the gluon jet fragmentation function at 14 and 18 GeV. In conjunction with our earlier results at 40 GeV, we then test QCD calculations for the en...

Abbiendi, G; Åkesson, P F; Alexander, G; Allison, J; Amaral, P; Anagnostou, G; Anderson, K J; Arcelli, S; Asai, S; Axen, D A; Azuelos, Georges; Bailey, I; Barberio, E; Barillari, T; Barlow, R J; Batley, J Richard; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, Siegfried; Biebel, O; Boeriu, O; Bock, P; Boutemeur, M; Braibant, S; Brigliadori, L; Brown, R M; Büsser, K; Burckhart, H J; Campana, S; Carnegie, R K; Caron, B; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Ciocca, C; Csilling, Akos; Cuffiani, M; Dado, S; de Roeck, A; De Wolf, E A; Desch, Klaus; Dienes, B; Donkers, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, Franco Luigi; Feld, L; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Fürtjes, A; Gagnon, P; Gary, J W; Gaycken, G; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Gross, E; Grunhaus, Jacob; Gruwé, M; Günther, P O; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harel, A; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, Richard J; Hensel, C; Herten, G; Heuer, R D; Hill, J C; Hoffman, K; Horváth, D; Igo-Kemenes, P; Ishii, K; Jeremie, H; Jovanovic, P; Junk, T R; Kanaya, N; Kanzaki, J; Karlen, Dean A; Kawagoe, K; Kawamoto, T; Keeler, Richard K; Kellogg, R G; Kennedy, B W; Klein, K; Klier, A; Kluth, S; Kobayashi, T; Kobel, M; Komamiya, S; Kormos, L L; Kramer, T; Krieger, P; Von Krogh, J; Krüger, K; Kühl, T; Kupper, M; Lafferty, G D; Landsman, Hagar Yaël; Lanske, D; Layter, J G; Lellouch, D; Letts, J; Levinson, L; Lillich, J; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, A; Ludwig, J; MacPherson, A; Mader, W; Marcellini, S; Martin, A J; Masetti, G; Mashimo, T; Mättig, P; McDonald, W J; McKenna, J A; McMahon, T J; McPherson, R A; Meijers, F; Menges, W; Merritt, F S; Mes, H; Michelini, Aldo; Mihara, S; Mikenberg, G; Miller, D J; Moed, S; Mohr, W; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; Nisius, R; O'Neale, S W; Oh, A; Okpara, A N; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Pilcher, J E; Pinfold, J L; Plane, D E; Poli, B; Polok, J; Pooth, O; Przybycien, M B; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Roney, J M; Rosati, S; Rozen, Y; Runge, K; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schieck, J; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Schwick, C; Scott, W G; Seuster, R; Shears, T G; Shen, B C; Sherwood, P; Skuja, A; Smith, A M; Sobie, R J; Söldner-Rembold, S; Spanó, F; Stahl, A; Stephens, K; Strom, D; Ströhmer, R; Tarem, S; Tasevsky, M; Teuscher, R; Thomson, M A; Torrence, E; Toya, D; Tran, P; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vollmer, C F; Vannerem, P; Vertesi, R; Verzocchi, M; Voss, H; Vossebeld, Joost Herman; Waller, D; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wetterling, D; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Zer-Zion, D; Zivkovic, L

2004-01-01T23:59:59.000Z

211

Dark jets in solar coronal holes  

E-Print Network [OSTI]

A new solar feature termed a dark jet is identified from observations of an extended solar coronal hole that was continuously monitored for over 44 hours by the EUV Imaging Spectrometer on board the Hinode spacecraft in 2011 February 8-10. Line-of-sight velocity maps derived from the coronal Fe XII $\\lambda$195.12 emission line, formed at 1.5 MK, revealed a number of large-scale, jet-like structures that showed significant blueshifts. The structures had either weak or no intensity signal in 193 A filter images from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, suggesting that the jets are essentially invisible to imaging instruments. The dark jets are rooted in bright points and occur both within the coronal hole and at the quiet Sun-coronal hole boundary. They exhibit a wide range of shapes, from narrow columns to fan-shaped structures, and sometimes multiple jets are seen close together. A detailed study of one dark jet showed line-of-sight speeds increasing along the jet axis fr...

Young, Peter R

2015-01-01T23:59:59.000Z

212

Jet Reconstruction in Heavy Ion Collisions  

E-Print Network [OSTI]

Measurements of strong suppression of inclusive hadron distributions and di-hadron correlations at high $p_{T}$, while providing evidence for partonic energy loss, also suffer from geometric biases due to the competition of energy loss and fragmentation. The measurements of fully reconstructed jets is expected to lack these biases as the energy flow is measured independently of the fragmentation details. In this article, we review the recent results from the heavy ion collisions collected by the STAR experiment at RHIC on direct jet reconstruction utilizing the modern sequential recombination and cone jet reconstruction algorithms together with their background subtraction techniques. In order to assess the jet reconstruction biases a comparison with the jet cross section measurement in $\\sqrt{s}=200$ GeV p+p collisions scaled by the number of binary nucleon-nucleon collisions to account for nuclear geometric effects is performed. Comparison of the inclusive jet cross section obtained in central Au+Au events with that in $p+p$ collisions, published previously by STAR, suggests that unbiased jet reconstruction in the complex heavy ion environment indeed may be possible.

Sevil Salur

2009-05-12T23:59:59.000Z

213

Composite Octet Searches with Jet Substructure  

SciTech Connect (OSTI)

Many new physics models with strongly interacting sectors predict a mass hierarchy between the lightest vector meson and the lightest pseudoscalar mesons. We examine the power of jet substructure tools to extend the 7 TeV LHC sensitivity to these new states for the case of QCD octet mesons, considering both two gluon and two b-jet decay modes for the pseudoscalar mesons. We develop both a simple dijet search using only the jet mass and a more sophisticated jet substructure analysis, both of which can discover the composite octets in a dijet-like signature. The reach depends on the mass hierarchy between the vector and pseudoscalar mesons. We find that for the pseudoscalar-to-vector meson mass ratio below approximately 0.2 the simple jet mass analysis provides the best discovery limit; for a ratio between 0.2 and the QCD-like value of 0.3, the sophisticated jet substructure analysis has the best discovery potential; for a ratio above approximately 0.3, the standard four-jet analysis is more suitable.

Bai, Yang; /SLAC; Shelton, Jessie; /Yale U.

2012-02-14T23:59:59.000Z

214

Application of a neptune propulsion concept to a manned mars excursion. Master's thesis  

SciTech Connect (OSTI)

NEPTUNE is a multimegawatt electric propulsion system. It uses a proven compact nuclear thermal rocket, NERVA, in a closed cycle with a magnetohydrodynamic (MHD) generator to power a magnetoplasmadynamic (MPD) thruster. This thesis defines constraints on an externally sourced propulsion system intended to carry out a manned Martian excursion. It assesses NEPTUNE's ability to conform to these constraints. Because an unmodified NEPTUNE system is too large, the thesis develops modifications to the system which reduce its size. The result is a far less proven, but more useful derivative of the unmodified NEPTUNE system.

Finley, C.J.

1993-04-01T23:59:59.000Z

215

Fuel-optimal Earth-Mars trajectories using low-thrust exhaust-modulated plasma propulsion  

E-Print Network [OSTI]

relerence frames Lx', y', r'I are different for the Earth and Mars references. The substitutions for the second-order derivatives required in the 27 differential equations are given by 2 VIM ISI CCS M + RM RM RM (2. 64) V V sin AM + RM cosltlM ( RM.... Characteristics of the Plasma Propulsion. . Equations of Motion. III NECESSARY CONDITIONS OF OPTIMALITY?. . . 14 15 16 30 Optimal Control Theory. Necessary Conditions of a Fuel-Optimal Earth-Mars Trajectory with Low-Thrust Plasma Propulsion...

Nah, Ren Sang

2012-06-07T23:59:59.000Z

216

Electron cyclotron resonant multicusp magnetic field microwave plasma source for electric propulsion  

SciTech Connect (OSTI)

The development of electrodeless microwave ion and plasma sources has been a recent, very active research project at Michigan State University. The results are efficient, compact microwave discharge configurations that operate at low pressures (0.5 mtorr to 100 mtorr) and efficiently produce low energy ions and free radicals and broad ion beams for oxidation, deposition, and etching experiments. The microwave discharge technology developed for these applications may be useful for application in electric propulsion. This paper reviews this microwave applicator technology and indicates how it may be extended to higher power levels and applied to electric propulsion systems. 12 references.

Dahimene, M.; Mahoney, L.; Asmussen, J.

1987-05-01T23:59:59.000Z

217

Problems in developing bimodal space power and propulsion system fuel element  

SciTech Connect (OSTI)

The paper discusses design of a space nuclear power and propulsion system fuel element (PPFE) developed on the basis of an enhanced single-cell thermionic fuel element (TFE) of the 'TOPAZ-2' thermionic converter-reactor (TCR), and presents the PPFE performance for propulsion and power modes of operation. The choice of UC-TaC fuel composition is substantiated. Data on hydrogen effect on the PPFE output voltage are presented, design solutions are considered that allow to restrict hydrogen supply to an interelectrode gap (IEG). Long-term geometric stability of an emitter assembly is supported by calculated data.

Nikolaev, Yu. V.; Gontar, A. S.; Zaznoba, V. A.; Parshin, N. Ya.; Ponomarev-Stepnoi, N. N.; Usov, V. A. [Research Institute of SIA 'Lutch' Podolsk, Moscow Region, 142100 (Russian Federation); RRC 'Kurchatov Institute' Moscow, 123182 (Russian Federation)

1997-01-10T23:59:59.000Z

218

Small Reactor Designs Suitable for Direct Nuclear Thermal Propulsion: Interim Report  

SciTech Connect (OSTI)

Advancement of U.S. scientific, security, and economic interests requires high performance propulsion systems to support missions beyond low Earth orbit. A robust space exploration program will include robotic outer planet and crewed missions to a variety of destinations including the moon, near Earth objects, and eventually Mars. Past studies, in particular those in support of both the Strategic Defense Initiative (SDI) and the Space Exploration Initiative (SEI), have shown nuclear thermal propulsion systems provide superior performance for high mass high propulsive delta-V missions. In NASA's recent Mars Design Reference Architecture (DRA) 5.0 study, nuclear thermal propulsion (NTP) was again selected over chemical propulsion as the preferred in-space transportation system option for the human exploration of Mars because of its high thrust and high specific impulse ({approx}900 s) capability, increased tolerance to payload mass growth and architecture changes, and lower total initial mass in low Earth orbit. The recently announced national space policy2 supports the development and use of space nuclear power systems where such systems safely enable or significantly enhance space exploration or operational capabilities. An extensive nuclear thermal rocket technology development effort was conducted under the Rover/NERVA, GE-710 and ANL nuclear rocket programs (1955-1973). Both graphite and refractory metal alloy fuel types were pursued. The primary and significantly larger Rover/NERVA program focused on graphite type fuels. Research, development, and testing of high temperature graphite fuels was conducted. Reactors and engines employing these fuels were designed, built, and ground tested. The GE-710 and ANL programs focused on an alternative ceramic-metallic 'cermet' fuel type consisting of UO2 (or UN) fuel embedded in a refractory metal matrix such as tungsten. The General Electric program examined closed loop concepts for space or terrestrial applications as well as open loop systems for direct nuclear thermal propulsion. Although a number of fast spectrum reactor and engine designs suitable for direct nuclear thermal propulsion were proposed and designed, none were built. This report summarizes status results of evaluations of small nuclear reactor designs suitable for direct nuclear thermal propulsion.

Bruce G. Schnitzler

2012-01-01T23:59:59.000Z

219

Excitation and propagation of Electrostatic Ion Cyclotron waves in rf-sustained plasmas of interest to propulsion research  

E-Print Network [OSTI]

it is thus necessary to heat these ions considerably. Various types of electrodeless plasma heating provideExcitation and propagation of Electrostatic Ion Cyclotron waves in rf-sustained plasmas of interest to propulsion research Rostislav Spektor and Edgar Y. Choueiri Electric Propulsion and Plasma Dynamics

Choueiri, Edgar

220

Abstract--A fish-like propulsion system seems to be an interesting and efficient alternative to propellers in small  

E-Print Network [OSTI]

1 Abstract--A fish-like propulsion system seems to be an interesting and efficient alternative. Finally there is a description of the control system implementation for the tail's motion. Index terms--Fish propulsion, underwater robot, fish design. I. INTRODUCTION LTHOUGH almost all marine vehicles use propellers

Papadopoulos, Evangelos

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

The CU Aerospace / VACCO Propulsion Unit for CubeSats (PUC) is a complete high-performance and  

E-Print Network [OSTI]

such as solar panels and magnetic torquers. For increased performance, or to meet customer specific missionThe CU Aerospace / VACCO Propulsion Unit for CubeSats (PUC) is a complete high necessary propulsion subsystems, including controller, power processing unit, micro-cavity discharge

Carroll, David L.

222

Jet production in ep collisions Pierre Van Mechelen  

E-Print Network [OSTI]

Jet production in ep collisions Pierre Van Mechelen University of Antwerpen Pierre electroproduction #12; Jet production in ep collisions Pierre Van Mechelen HERA, H1 and ZEUS H1 ZEUS p (920 GeV) e ± (27.6 GeV) #12; Jet production in ep collisions Pierre Van Mechelen Jet finding algorithms Clustering

223

Jet physics and the underlying event at the Tevatron  

SciTech Connect (OSTI)

Tevatron Run 2 results on the inclusive jet cross section (MidPoint and K{sub T} algorithm) and the b-jet and b{bar b}-jet cross section (MidPoint algorithm) are presented and compared with theory. The CDF b-jet {bar b}-jet {Delta}{phi} distribution is compared with theory and with the D0 jet No.1-jet No.2 {Delta}{phi} distribution. The understanding and modeling of the ''underlying event'' in Run 2 at the Tevatron is reviewed and new CDF results are presented.

Field, Rick; /Florida U.

2005-08-01T23:59:59.000Z

224

Jet spoiler arrangement for wind turbine  

DOE Patents [OSTI]

An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the ends thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby inducing stall conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.

Cyrus, Jack D. (Corrales, NM); Kadlec, Emil G. (Albuquerque, NM); Klimas, Paul C. (Albuquerque, NM)

1985-01-01T23:59:59.000Z

225

Jet spoiler arrangement for wind turbine  

DOE Patents [OSTI]

An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the end thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby including stall conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.

Cyrus, J.D.; Kadlec, E.G.; Klimas, P.C.

1983-09-15T23:59:59.000Z

226

Squark and gluino production with jets  

SciTech Connect (OSTI)

We present cross section predictions for squark and gluino production at the LHC, in association with up to two additional hard jets. These cross sections can be very large in comparison to the inclusive Born rates. Because hadron collider experiments utilize hard jets in the reconstruction of cascade decays or as a way to separate squark and gluino production, the understanding of these processes is crucial. We show to what degree hard jet radiation can be described by shower algorithms and point out how tuning these showers, for example to top quark pair production, could help reduce theoretical uncertainties for new physics searches at the LHC.

Plehn, T.; /Munich, Max Planck Inst.; Rainwater, D.; /Rochester U.; Skands, P.; /Fermilab

2005-10-01T23:59:59.000Z

227

Hypersonic Buckshot: Astrophysical Jets as Heterogeneous Collimated Plasmoids  

E-Print Network [OSTI]

Herbig-Haro (HH) jets are commonly thought of as homogeneous beams of plasma traveling at hypersonic velocities. Structure within jet beams is often attributed to periodic or ``pulsed'' variations of conditions at the jet source. Simulations based on this scenario result in knots extending across the jet diameter. Observations and recent high energy density laboratory experiments shed new light on structures below this scale and indicate they may be important for understanding the fundamentals of jet dynamics. In this paper we offer an alternative to ``pulsed'' models of protostellar jets. Using direct numerical simulations we explore the possibility that jets are chains of sub-radial clumps propagating through a moving inter-clump medium. Our models explore an idealization of this scenario by injecting small ($r\\rho_{jet}$) spheres embedded in an otherwise smooth inter-clump jet flow. The spheres are initialized with velocities differing from the jet velocity by $\\sim15$%. We find the consequences of shiftin...

Yirak, Kristopher; Cunningham, Andrew J; Mitran, Sorin

2008-01-01T23:59:59.000Z

228

Figure 2: The mercury jet target geometry. The proton beam and mercury jet cross at z=-37.5 cm.  

E-Print Network [OSTI]

Figure 2: The mercury jet target geometry. The proton beam and mercury jet cross at z=-37.5 cm. Figure 3: The layout of multiple proton beam entry directions relative to mercury jet at z=-75 cm. A PION of a free liquid mercury jet with an intense proton beam. We study the variation of meson production

McDonald, Kirk

229

Di-jet hadron pair correlation in a hydrodynamical model with a quenching jet  

E-Print Network [OSTI]

In jet quenching, a hard QCD parton, before fragmenting into a jet of hadrons, deposits a fraction of its energy in the medium, leading to suppressed production of high-$p_T$ hadrons. Assuming that the deposited energy quickly thermalizes, we simulate the subsequent hydrodynamic evolution of the QGP fluid. Hydrodynamic evolution and subsequent particle emission depend on the jet trajectories. Azimuthal distribution of excess $\\pi^-$ due to quenching jet, averaged over all the trajectories, reasonably well reproduce the di-hadron correlation as measured by the STAR and PHENIX collaboration in central and in peripheral Au+Au collisions.

A. K. Chaudhuri

2008-01-15T23:59:59.000Z

230

Feasibility Study for a New Business Jet  

E-Print Network [OSTI]

This report demonstrates details of a feasibility study of a new business jet as an effort to complete the requirements for a field project (EMGT 835) in Engineering Management. The study is conducted during global economic crisis to identify a...

Mousa, Yasser Abdullah

2009-05-15T23:59:59.000Z

231

Inclusive jet cross section at CDF  

SciTech Connect (OSTI)

This contribution reports on preliminary measurements of the inclusive jet production cross section in p{bar p} collisions at {radical}s = 1.96 TeV using data collected with CDF corresponding to an integrated luminosity of 385 pb{sup -1}. Two analyzes are presented: one uses the longitudinally invariant k{sub T} algorithm to reconstruct the jets, the other uses the midpoint algorithm. Both are limited to jets with rapidity in the range 0.1 < |y{sup jet}| < 0.7. The measured cross sections are in good agreement with next-to-leading order perturbative QCD predictions after including the non-perturbative corrections necessary to account for underlying event and hadronization effects.

Lefevre, R.; Martinez, M.; /Barcelona, IFAE

2005-01-01T23:59:59.000Z

232

Measuring collinear W emissions inside jets  

E-Print Network [OSTI]

Single and multiple emission of electroweak gauge bosons and in particular of W bosons is discussed in the parton shower language. Algorithms and observables for the reconstruction of both leptonically and hadronically decaying W bosons inside light quark jets are compared, and they are applied to a study of how emission rates of W bosons in light-jet events at the LHC could be measured.

Frank Krauss; Petar Petrov; Marek Schoenherr; Michael Spannowsky

2014-03-19T23:59:59.000Z

233

New results on jet fragmentation at CDF  

SciTech Connect (OSTI)

Presented are the latest results of jet fragmentation studies at the Tevatron using the CDF Run II detector. Studies include the distribution of transverse momenta (Kt) of particles jets, two-particle momentum correlations, and indirectly global event shapes in p{bar p} collisions. Results are discussed within the context of recent Next-to-Leading Log calculations as well as earlier experimental results from the Tevatron and e{sup +}e{sup -} colliders.

Jindariani, Sergo; /Florida U.

2006-12-01T23:59:59.000Z

234

Importance of Nuclear DataImportance of Nuclear Data to the Naval Nuclear Propulsion Program  

E-Print Network [OSTI]

Importance of Nuclear DataImportance of Nuclear Data to the Naval Nuclear Propulsion Program Don Cores · Project Prometheus · Some Very Recent Criticality Analyses #12;Use of Early RPI Measurements · Criticality Analyses of Under-moderated Systemsy y y · Most Reactive Condition ­ Highest Water Density

Danon, Yaron

235

Electric Motor Drive Selection Issues for HEV Propulsion Systems: A Comparative Study  

E-Print Network [OSTI]

Electric Motor Drive Selection Issues for HEV Propulsion Systems: A Comparative Study M. Zeraoulia1 Combustion Engine (ICE) and the electric motor to deliver power in parallel to drive the wheels. Since both the ICE and electric motor are generally coupled to the drive shaft of the wheels via two clutches

Paris-Sud XI, Université de

236

Dedicated Laboratory Setup for CO{sub 2} TEA Laser Propulsion Experiments at Rensselaer Polytechnic Institute  

SciTech Connect (OSTI)

Laser propulsion research progress has traditionally been hindered by the scarcity of photon sources with desirable characteristics, as well as integrated specialized flow facilities in a dedicated laboratory environment. For TEA CO{sub 2} lasers, the minimal requirements are time-average powers of >100 W), and pulse energies of >10 J pulses with short duration (e.g., 0.1 to 1 {mu}s); furthermore, for the advanced pulsejet engines of interest here, the laser system must simulate pulse repetition frequencies of 1-10 kilohertz or more, at least for two (carefully sequenced) pulses. A well-equipped laser propulsion laboratory should have an arsenal of sensor and diagnostics tools (such as load cells, thrust stands, moment balances, pressure and heat transfer gages), Tesla-level electromagnet and permanent magnets, flow simulation facilities, and high-speed visualization systems, in addition to other related equipment, such as optics and gas supply systems. In this paper we introduce a cutting-edge Laser Propulsion Laboratory created at Rensselaer Polytechnic Institute, one of the very few in the world to be uniquely set up for beamed energy propulsion (BEP) experiments. The present BEP research program is described, along with the envisioned research strategy that will exploit current and expanded facilities in the near future.

Salvador, Israel I.; Kenoyer, David; Myrabo, Leik N.; Notaro, Samuel [Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180 (United States)

2010-10-08T23:59:59.000Z

237

JOURNAL OF PROPULSION AND POWER Vol. 20, No. 6, NovemberDecember 2004  

E-Print Network [OSTI]

of Hall thrusters.1 High-energy exhaust par- ticles interact with the neutral background particles through to the panel. This paper reports on a neutral background pressure map of a vacuum chamber that is used to val and Electric Propulsion Laboratory, Department of Aerospace Engineering, 1052 FXB Building, 1320 Beal Avenue

Walker, Mitchell

238

Research, development and demonstration of nickel-zinc batteries for electric vehicle propulsion. Annual report, 1979  

SciTech Connect (OSTI)

Activities in a program to develop a Ni/Zn battery for electric vehicle propulsion are reported. Aspects discussed include battery design and development, nickel cathode study, and basic electrochemistry. A number of engineering drawings are supplied. 61 figures, 11 tables. (RWR)

Not Available

1980-06-01T23:59:59.000Z

239

Research, development, and demonstration of lead-acid batteries for electric vehicle propulsion. Annual report, 1980  

SciTech Connect (OSTI)

The progress and status of Eltra's Electric Vehicle Battery Program during FY-80 are presented under five divisional headings: Research on Components and Processes; Development of Cells and Modules for Electric Vehicle Propulsion; Sub-Systems; Pilot Line Production of Electric Vehicle Battery Prototypes; and Program Management.

Not Available

1981-03-01T23:59:59.000Z

240

National Aeronautics and Space Administration In-Space propulSIon SyStemS roadmap  

E-Print Network [OSTI]

, such as electric propulsion, are commonly used for station keeping on commer- cial co 02 Mike Meyer, Co-chair Les Johnson, Co-chair Bryan Palaszewski Dan Goebel Harold White David Coote TA02-1 1. General Overview TA02-2 1.1. Technical Approach TA02-2 1.2. Benefits TA02-5 1

Waliser, Duane E.

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

The CU Aerospace / VACCO CubeSat High Impulse Propulsion System (CHIPS) offers a miniaturized and  

E-Print Network [OSTI]

· Overall control authority: roll, pitch, yaw, +/- Z · On-orbit update of system parameters, including · System two-failure-tolerant against leakage · Life span: 2+ years from propellant load. · HighThe CU Aerospace / VACCO CubeSat High Impulse Propulsion System (CHIPS) offers a miniaturized

Carroll, David L.

242

Modeling the Characteristics of Propulsion Systems Providing Less Than 10 N Thrust  

E-Print Network [OSTI]

. Chiasson, Paulo C. Lozano May 2012 SSL#8-12 1 #12;2 #12;Modeling the Characteristics of Propulsion Systems Providing Less Than 10 N Thrust Thomas M. Chiasson, Paulo C. Lozano May 2012 SSL#8-12 1 1 This work is based

243

A Critical History of Electric Propulsion: The First Fifty Years (1906-1956)  

E-Print Network [OSTI]

m = Propellant mass flow rate P = Input electric power p P/Mv = Input electric power per unit Physics Group, MAE Department. e-mail: choueiri@princeton.edu. Presented at the 40th AIAA/ASME by the AIAA with permission. Also published in the Journal of Propulsion and Power, Vol. 20, No. 2, pp. 193

Choueiri, Edgar

244

The Infrared Jet in 3C31  

E-Print Network [OSTI]

We report the detection of infrared emission from the jet of the nearby FR I radio galaxy 3C 31. The jet was detected with the IRAC instrument on Spitzer at 4.5 micron, 5.8 micron, and 8.0 micron out to 30" (13 kpc) from the nucleus. We measure radio, infrared, optical, and X-ray fluxes in three regions along the jet determined by the infrared and X-ray morphology. Radio through X-ray spectra in these regions demonstrate that the emission can be interpreted as synchrotron emission from a broken power-law distribution of electron energies. We find significant differences in the high energy spectra with increasing distance from the nucleus. Specifically, the high energy slope increases from 0.86 to 1.72 from 1 kpc to 12 kpc along the jet, and the spectral break likewise increases in frequency along the jet from 10-100's of GHz to ~20 THz. Thus the ratio of IR to X-ray flux in the jet increases by at least an order of magnitude with increasing distance from the nucleus. We argue that these changes cannot simply ...

Lanz, Lauranne; Kraft, Ralph P; Birkinshaw, Mark; Lal, Dharam V; Forman, William R; Jones, Christine; Worrall, Diana M

2015-01-01T23:59:59.000Z

245

Sound Waves from Quenched Jets  

E-Print Network [OSTI]

Heavy ion collisions at RHIC/LHC energies are well described by the (nearly ideal) hydrodynamics. Last year this success has been extended to higher angular harmonics, $v_n,n=3..9$ induced by initial-state perturbations, in analogy to cosmic microwave background fluctuations. Here we use hydrodynamics to study sound propagation emitted by quenched jets. We use the so called "geometric acoustics" to follow the sound propagation, on top of the expanding fireball. The conical waves, known as "Mach cones", turn out to be strongly distorted. We show that large radial flow makes the observed particle spectra to be determined mostlly by the vicinity of their intersection with the fireball's space-like and time-like freezeout surfaces. We further show how the waves modify the freezeout surfaces and spectra. We end up comparing our calculations to the two-particle correlation functions at RHIC, while emphasizing that studies of dijet events observed at LHC should provide much better test of our theory.

Vladimir Khachatryan; Edward Shuryak

2011-08-15T23:59:59.000Z

246

PHOTOSPHERIC EMISSION FROM STRATIFIED JETS  

SciTech Connect (OSTI)

We explore photospheric emissions from stratified two-component jets, wherein a highly relativistic spine outflow is surrounded by a wider and less relativistic sheath outflow. Thermal photons are injected in regions of high optical depth and propagated until the photons escape at the photosphere. Because of the presence of shear in velocity (Lorentz factor) at the boundary of the spine and sheath region, a fraction of the injected photons are accelerated using a Fermi-like acceleration mechanism such that a high-energy power-law tail is formed in the resultant spectrum. We show, in particular, that if a velocity shear with a considerable variance in the bulk Lorentz factor is present, the high-energy part of observed gamma-ray bursts (GRBs) photon spectrum can be explained by this photon acceleration mechanism. We also show that the accelerated photons might also account for the origin of the extra-hard power-law component above the bump of the thermal-like peak seen in some peculiar bursts (e.g., GRB 090510, 090902B, 090926A). We demonstrate that time-integrated spectra can also reproduce the low-energy spectrum of GRBs consistently using a multi-temperature effect when time evolution of the outflow is considered. Last, we show that the empirical E{sub p}-L{sub p} relation can be explained by differences in the outflow properties of individual sources.

Ito, Hirotaka; Nagataki, Shigehiro; Ono, Masaomi; Lee, Shiu-Hang; Mao, Jirong [Astrophysical Big Bang Laboratory, RIKEN, Saitama 351-0198 (Japan); Yamada, Shoichi [Department of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan); Pe'er, Asaf [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Mizuta, Akira [KEK Theory Center, Tsukuba 305-0801 (Japan); Harikae, Seiji, E-mail: hito@yukawa.kyoto-u.ac.jp [Quants Research Department, Financial Engineering Division, Mitsubishi UFJ Morgan Stanley Securities Co., Ltd., Mejirodai Bldg., 3-29-20 Mejirodai, Bunkyo-ku, Tokyo 112-8688 (Japan)

2013-11-01T23:59:59.000Z

247

Particle multiplicity of unbiased gluon jets from $e^+ e^-$ three-jet events  

E-Print Network [OSTI]

The charged particle multiplicities of two- and three-jet events from the reaction e+e- -> Z0 -> hadrons are measured for Z0 decays to light quark (uds) flavors. Using recent theoretical expressions to account for biases from event selection, results corresponding to unbiased gluon jets are extracted over a range of jet energies from about 11 to 30 GeV. We find consistency between these results and direct measurements of unbiased gluon jet multiplicity from upsilon and Z0 decays. The unbiased gluon jet data including the direct measurements are compared to corresponding results for quark jets. We perform fits based on analytic expressions for particle multiplicity in jets to determine the ratio r = Ng/Nq of multiplicities between gluon and quark jets as a function of energy. We also determine the ratio of slopes, r(1) = (dNg/dy)/(dNq/dy), and of curvatures, r(2) = (d2Ng/dy2)/(d2Nq/dy2), where y specifies the energy scale. At 30 GeV, we find r = 1.422 +/- 0.051, r(1) = 1.761 +/- 0.071 and r(2) = 1.98 +/- 0.13,...

Abbiendi, G; Åkesson, P F; Alexander, Gideon; Allison, J; Anagnostou, G; Anderson, K J; Arcelli, S; Asai, S; Axen, D A; Azuelos, Georges; Bailey, I; Barberio, E; Barlow, R J; Batley, J Richard; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, Siegfried; Biebel, O; Bloodworth, Ian J; Boeriu, O; Bock, P; Böhme, J; Bonacorsi, D; Boutemeur, M; Braibant, S; Brigliadori, L; Brown, R M; Burckhart, H J; Cammin, J; Campana, S; Carnegie, R K; Caron, B; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Clarke, P E L; Clay, E; Cohen, I; Couchman, J; Csilling, Akos; Cuffiani, M; Dado, S; Dallavalle, G M; Dallison, S; de Roeck, A; De Wolf, E A; Dervan, P J; Desch, Klaus; Dienes, B; Donkers, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, Franco Luigi; Feld, L; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Fürtjes, A; Futyan, D I; Gagnon, P; Gary, J W; Gaycken, G; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Graham, K; Gross, E; Grunhaus, Jacob; Gruwé, M; Günther, P O; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harder, K; Harel, A; Harin-Dirac, M; Hauschild, M; Hauschildt, J; Hawkes, C M; Hawkings, R; Hemingway, Richard J; Hensel, C; Herten, G; Heuer, R D; Hill, J C; Hoffman, K; Homer, R James; Horváth, D; Hossain, K R; Howard, R; Hüntemeyer, P; Igo-Kemenes, P; Ishii, K; Jawahery, A; Jeremie, H; Jones, C R; Jovanovic, P; Junk, T R; Kanaya, N; Kanzaki, J; Karapetian, G V; Karlen, D A; Kartvelishvili, V G; Kawagoe, K; Kawamoto, T; Keeler, Richard K; Kellogg, R G; Kennedy, B W; Kim, D H; Klein, K; Klier, A; Kluth, S; Kobayashi, T; Kobel, M; Kokott, T P; Komamiya, S; Kowalewski, R V; Kramer, T; Kress, T; Krieger, P; Von Krogh, J; Krop, D; Kühl, T; Kupper, M; Kyberd, P; Lafferty, G D; Landsman, Hagar Yaël; Lanske, D; Lawson, I; Layter, J G; Leins, A; Lellouch, Daniel; Letts, J; Levinson, L; Lillich, J; Littlewood, C; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, J; Macchiolo, A; MacPherson, A L; Mader, W; Marcellini, S; Marchant, T E; Martin, A J; Martin, J P; Martínez, G; Masetti, G; Mashimo, T; Mättig, P; McDonald, W J; McKenna, J A; McMahon, T J; McPherson, R A; Meijers, F; Méndez-Lorenzo, P; Menges, W; Merritt, F S; Mes, H; Michelini, Aldo; Mihara, S; Mikenberg, G; Miller, D J; Moed, S; Mohr, W; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Neal, H A; Nisius, R; O'Neale, S W; Oh, A; Okpara, A N; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Patrick, G N; Pilcher, J E; Pinfold, James L; Plane, D E; Poli, B; Polok, J; Pooth, O; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Rick, Hartmut; Rodning, N L; Roney, J M; Rosati, S; Roscoe, K; Rozen, Y; Runge, K; Rust, D R; Sachs, K; Saeki, T; Sahr, O; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schröder, M; Schumacher, M; Schwick, C; Scott, W G; Seuster, R; Shears, T G; Shen, B C; Shepherd-Themistocleous, C H; Sherwood, P; Skuja, A; Smith, A M; Snow, G A; Sobie, Randall J; Söldner-Rembold, S; Spagnolo, S; Spanó, F; Sproston, M; Stahl, A; Stephens, K; Strom, D; Ströhmer, R; Stumpf, L; Surrow, B; Tarem, S; Tasevsky, M; Taylor, R J; Teuscher, R; Thomas, J; Thomson, M A; Torrence, E; Toya, D; Trefzger, T M; Tricoli, A; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vachon, B; Vollmer, C F; Vannerem, P; Verzocchi, M; Voss, H; Vossebeld, Joost Herman; Waller, D; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wetterling, D; Wilson, G W; Wilson, J A; Wyatt, T R; Yamashita, S; Zacek, V; Zer-Zion, D; 10.1007/s100520200926

2002-01-01T23:59:59.000Z

248

Jet vetoes versus giant K-factors in the exclusive Z+1-jet cross section  

E-Print Network [OSTI]

The ATLAS measurement of the exclusive $Z$+1-jet cross section shows a surprising agreement with fixed-order predictions in the kinematic region expected to be dominated by large jet-veto logarithms. We identify the explanation for this effect: the jet-isolation criterion implemented by ATLAS allows dijet events where an energetic jet is collinear to a final-state lepton. This process contains a giant K-factor arising from the collinear emission of a Z-boson from the dijet configuration which overwhelms the effect of the jet-veto logarithms. We provide numerical results for 7 TeV, 8 TeV and 14 TeV LHC collisions that demonstrate the interplay between the jet-veto logarithms and the giant K-factor in the theoretical prediction. We suggest an alternate isolation criterion that removes the giant K-factor and allows for a direct test of the jet-veto resummation framework in the Z+1-jet process.

Boughezal, Radja; Liu, Xiaohui

2015-01-01T23:59:59.000Z

249

MULTIWAVELENGTH OBSERVATIONS OF THE SS 433 JETS  

SciTech Connect (OSTI)

We present observations of the SS 433 jets using the Chandra High Energy Transmission Grating Spectrometer with contemporaneous optical and Very Long Baseline Array observations. The X-ray and optical emission line regions are found to be related but not coincident as the optical line emission persists for days while the X-ray emission lines fade in less than 5000 s. The line Doppler shifts from the optical and X-ray lines match well, indicating that they are less than 3 × 10{sup 14} cm apart. The jet Doppler shifts show aperiodic variations that could result from shocks in interactions with the local environment. These perturbations are consistent with a change in jet direction but not jet speed. The proper motions of the radio knots match the kinematic model only if the distance to SS 433 is 4.5 ± 0.2 kpc. Observations during eclipse show that the occulted emission is very hard, seen only above 2 keV and rising to comprise >50% of the flux at 8 keV. The soft X-ray emission lines from the jet are not blocked, constraining the jet length to ?> 2 × 10{sup 12} cm. The base jet density is in the range 10{sup 10-13} cm{sup –3}, in contrast to our previous estimate based on the Si XIII triplet, which is likely to have been affected by UV de-excitation. There is a clear overabundance of Ni by a factor of about 15 relative to the solar value, which may have resulted from an unusual supernova that formed the compact object.

Marshall, Herman L.; Canizares, Claude R.; Schulz, Norbert S.; Nowak, Michael [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Hillwig, Todd [Department of Physics and Astronomy, Valparaiso University, Valparaiso, IN 46383 (United States); Mioduszewski, Amy; Rupen, Michael [NRAO, P.O. Box 2, Socorro, NM 87801 (United States); Heinz, Sebastian, E-mail: hermanm@space.mit.edu, E-mail: crc@space.mit.edu, E-mail: nss@space.mit.edu, E-mail: mnowak@space.mit.edu, E-mail: todd.hillwig@valpo.edu, E-mail: amiodusz@nrao.edu, E-mail: mrupen@aoc.nrao.edu, E-mail: heinzs@astro.wisc.edu [Astronomy Department, 5408 Sterling Hall, University of Wisconsin, Madison, WI 53706 (United States)

2013-09-20T23:59:59.000Z

250

E-Print Network 3.0 - african easterly jet Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

EasterlyEasterly Jet (AEJ) :Jet (AEJ) : Vent thermique d'Est principalement li ... Nord lors de la priode de mousson. TropicalTropical EasterlyEasterly Jet (TEJ) :Jet (TEJ)...

251

Received 22 May 2013 | Accepted 22 Jan 2014 | Published 18 Feb 2014 Bending rules for animal propulsion  

E-Print Network [OSTI]

or water. Models of animal propulsion often emulate patterns that have been established for hydrofoils structure that oscillates through the surrounding fluid with varying types of heaving and pitching motions6

Dabiri, John O.

252

AMER. ZOOL.,36:628-641 (1996) Transitions from Drag-based to Lift-based Propulsion in  

E-Print Network [OSTI]

aquatic mammals use lift-based propulsion with oscillating hydrofoils. Aerobic efficiencies are low- ficiency are maximized by swimming modes that use a lift-based oscillating hy- drofoil (i.e., cetacean

Fish, Frank

253

The Design and Feasibility of a 10 mN Chemical Space Propulsion Alexander Bruccoleri , Paulo Lozano  

E-Print Network [OSTI]

-1,400 to provide additional data to the community. The nozzle's coefficient of thrust efficiency is approximately class space propulsion systems and recommendations are given for propellant choice, valve and pump

254

A study of the self-oscillating jet impingement nozzle  

E-Print Network [OSTI]

wave and flow fluctuations that need no external input. The new oscillating jet when used for impingement surface transport was labeled the Self-Oscillating Jet Impingement Nozzle. The objectives of this research were to characterize the gains in heat...

Chinnock, Paul Scott

1993-01-01T23:59:59.000Z

255

Applications of Underexpanded Jets in Hypersonic Aerothermodynamics Research  

E-Print Network [OSTI]

Applications of Underexpanded Jets in Hypersonic Aerothermodynamics Research Vladimir V. Riabov Abstract. A method of underexpanded hypersonic viscous jets has been developed to acquire experimental parameters are revealed. In the case of hypersonic stabilization, the Reynolds number and temperature factor

Riabov, Vladimir V.

256

Feedback control of flow separation using synthetic jets  

E-Print Network [OSTI]

The primary goal of this research is to assess the effect of synthetic jets on flow separation and provide a feedback control strategy for flow separation using synthetic jets. The feedback control synthesis is conducted based upon CFD simulation...

Kim, Kihwan

2006-04-12T23:59:59.000Z

257

Images in Emergency Medicine: Irritant Contact Dermatitis from Jet Fuel  

E-Print Network [OSTI]

and penetration of JP-8 jet fuel and its components. Toxicoland other kerosene-based fuels have been shown to cause skinContact Dermatitis from Jet Fuel Christopher C. Trigger, MD

Trigger, Christopher C; Eilbert, Wesley

2009-01-01T23:59:59.000Z

258

Active noise control of supersonic impinging jet using pulsed microjets  

E-Print Network [OSTI]

This thesis concerns an active noise control of supersonic impinging jet flow using unsteady microjet injection. Supersonic impinging jet involves several problems such as lift loss, ground erosion, significant noise ...

Hong, Seung Hyuck

2009-01-01T23:59:59.000Z

259

Use Steam Jet Ejectors or Thermocompressors to Reduce Venting...  

Broader source: Energy.gov (indexed) [DOE]

Steam Jet Ejectors or Thermocompressors to Reduce Venting of Low-Pressure Steam Use Steam Jet Ejectors or Thermocompressors to Reduce Venting of Low-Pressure Steam This tip sheet...

260

Mixing enhancement by use of swirling jets  

SciTech Connect (OSTI)

It has been proposed that the mixing of fuel with air in the combustor of scramjet engines might be enhanced by the addition of swirl to the fuel jet prior to injection. This study investigated the effects of swirl on the mixing of a 30 deg wall jet into a Mach 2 flow. Cases with swirl and without swirl were investigated, with both helium and air simulating the fuel. Rayleigh scattering was used to visualize the flow, and seeding the fuel with water allowed it to be traced through the main flow. The results show that the addition of swirl to the fuel jet causes the fuel to mix more rapidly with the main flow, that larger amounts of swirl increase this effect, and that helium spreads better into the main flow than air. 12 refs.

Kraus, D.K.; Cutler, A.D.

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Extragalactic jets on subpc and large scales  

E-Print Network [OSTI]

Jets can be probed in their innermost regions (d~0.1 pc) through the study of the relativistically-boosted emission of blazars. On the other extreme of spatial scales, the study of structure and dynamics of extragalactic relativistic jets received renewed impulse after the discovery, made by Chandra, of bright X-ray emission from regions at distances larger than hundreds of kpc from the central engine. At both scales it is thus possible to infer some of the basic parameters of the flow (speed, density, magnetic field intensity, power). After a brief review of the available observational evidence, I discuss how the comparison between the physical quantities independently derived at the two scales can be used to shed light on the global dynamics of the jet, from the innermost regions to the hundreds of kpc scale.

F. Tavecchio

2007-08-20T23:59:59.000Z

262

On the Misalignment of Jets in Microquasars  

E-Print Network [OSTI]

We discuss the timescales for alignment of black hole and accretion disc spins in the context of binary systems. We show that for black holes that are formed with substantial angular momentum, the alignment timescales are likely to be at least a substantial fraction of the systems' lifetimes. This result explains the observed misalignment of the disc and the jet in the microquasar GRO J 1655-40 and in SAX J 1819-2525 as being likely due to the Bardeen-Petterson effect. We discuss the implications of these results on the mass estimate for GRS 1915+105, which has assumed the jet is perpendicular to the orbital plane of the system and may hence be an underestimate. We show that the timescales for the spin alignment in Cygnus X-3 are consistent with the likely misalignment of disc and jet in that system, and that this is suggested by the observational data.

Thomas J. Maccarone

2002-09-05T23:59:59.000Z

263

Jet Structure in Heavy Ion Collisions  

E-Print Network [OSTI]

We review recent theoretical developments in the study of the structure of jets that are produced in ultra relativistic heavy ion collisions. The core of the review focusses on the dynamics of the parton cascade that is induced by the interactions of a fast parton crossing a quark-gluon plasma. We recall the basic mechanisms responsible for medium induced radiation, underline the rapid disappearance of coherence effects, and the ensuing probabilistic nature of the medium induced cascade. We discuss how large radiative corrections modify the classical picture of the gluon cascade, and how these can be absorbed in a renormalization of the jet quenching parameter $\\hat q $. Then, we analyze the (wave)-turbulent transport of energy along the medium induced cascade, and point out the main characteristics of the angular structure of such a cascade. Finally, color decoherence of the in-cone jet structure is discussed. Modest contact with phenomenology is presented towards the end of the review.

Blaizot, Jean-Paul

2015-01-01T23:59:59.000Z

264

Research, development, and demonstration of nickel-iron batteries for electric vehicle propulsion. Annual report, 1980  

SciTech Connect (OSTI)

The objective of the Eagle-Picher nickel-iron battery program is to develop a nickel-iron battery for use in the propulsion of electric and electric-hybrid vehicles. To date, the program has concentrated on the characterization, fabrication and testing of the required electrodes, the fabrication and testing of full-scale cells, and finally, the fabrication and testing of full-scale (270 AH) six (6) volt modules. Electrodes of the final configuration have now exceeded 1880 cycles and are showing minimal capacity decline. Full-scale cells have presently exceeded 600 cycles and are tracking the individual electrode tests almost identically. Six volt module tests have exceeded 500 cycles, with a specific energy of 48 Wh/kg. Results to date indicate the nickel-iron battery is beginning to demonstrate the performance required for electric vehicle propulsion.

Not Available

1981-03-01T23:59:59.000Z

265

On self-propulsion of $N$-sphere micro-robot  

E-Print Network [OSTI]

The aim of this paper is to describe the self-propulsion of a micro-robot (or micro-swimmer) consisting of $N$ spheres moving along a fixed line. The spheres are linked to each other by arms with the lengths changing periodically. For the derivation, we use the asymptotic procedure containing the two-timing method and a distinguished limit. We show that in the main approximation, the self-propulsion velocity appears as a linear combination of velocities of all possible triplets of spheres. Velocities and efficiencies of three-, four-, and five-swimmers are calculated. The paper is devoted to H.K.Moffatt, who initiated the author's interests in low-Reynolds-number fluid dynamics.

Vladimir A. Vladimirov

2012-09-02T23:59:59.000Z

266

Comparison of Space Propulsion Methods for a Manned Mission to Mars  

E-Print Network [OSTI]

We undertake a comparison of the latest developments in propulsion technologies, for a manned mission to Mars. The main objective is to assess the possibility of reducing travel time keeping the mass at departure within bounds. For the sake of comparison we used representative systems of different state of the art or proposed technologies, from the chemical engine to the "Pure Electro-Magnetic Thrust" (PEMT) concept, using a nuclear engine proposed by Rubbia. A mission architecture is suggested, based on existing mission proposals to Mars, to estimate the mass budget that influences the performance of the propulsion system. The trajectory of the spacecraft is determined by a numerical integration of the equations of motion and a partial optimization procedure, for the interplanetary phase with continuous thrust, and by conics and instant manoeuvres in the regions of influence of the departure and arrival planets. Pareto curves of the duration of the mission and time of flight versus mass of mission are drawn....

Guerra, A G C; Gil, P J S

2015-01-01T23:59:59.000Z

267

Current Development of Nuclear Thermal Propulsion technologies at the Center for Space Nuclear Research  

SciTech Connect (OSTI)

Nuclear power and propulsion has been considered for space applications since the 1950s. Between 1955 and 1972 the US built and tested over twenty nuclear reactors / rocket engines in the Rover/NERVA programs1. The Aerojet Corporation was the prime contractor for the NERVA program. Modern changes in environmental laws present challenges for the redevelopment of the nuclear rocket. Recent advances in fuel fabrication and testing options indicate that a nuclear rocket with a fuel composition that is significantly different from those of the NERVA project can be engineered; this may be needed to ensure public support and compliance with safety requirements. The Center for Space Nuclear Research (CSNR) is pursuing a number of technologies, modeling and testing processes to further the development of safe, practical and affordable nuclear thermal propulsion systems.

Robert C. O'Brien; Steven K. Cook; Nathan D. Jerred; Steven D. Howe; Ronald Samborsky; Daniel Brasuell

2012-09-01T23:59:59.000Z

268

QCD Jet Rates with the Inclusive Generalized kt Algorithms  

E-Print Network [OSTI]

We derive generating functions, valid to next-to-double logarithmic accuracy, for QCD jet rates according to the inclusive forms of the kt, Cambridge/Aachen and anti-kt algorithms, which are equivalent at this level of accuracy. We compare the analytical results with jet rates and average jet multiplicities from the SHERPA event generator, and study the transition between Poisson-like and staircase-like behaviour of jet ratios.

Erik Gerwick; Ben Gripaios; Steffen Schumann; Bryan Webber

2013-04-15T23:59:59.000Z

269

On the Counter-jet Emission in GRB Afterglows  

SciTech Connect (OSTI)

We investigate the dynamical evolution of double-sided jets and present detailed numerical studies on the emission from the receding jet of gamma-ray bursts. It is found that the receding jet emission is generally very weak and only manifests as a plateau in the late time radio afterglow light curves. Additionally, we find that the effect of synchrotron self-absorption can influence the peak time of the receding jet emission significantly.

Wang Xin; Huang, Y. F. [Department of Astronomy, Nanjing University, Nanjing 210093 (China)

2010-10-15T23:59:59.000Z

270

Gauge/gravity duality and jets in strongly coupled plasma  

E-Print Network [OSTI]

We discuss jets in strongly coupled N = 4 supersymmetric Yang-Mills plasma and their dual gravitational description.

Paul M. Chesler

2009-10-08T23:59:59.000Z

271

THE HELICAL JET OF THE VELA PULSAR  

SciTech Connect (OSTI)

We have studied the fascinating dynamics of the nearby Vela pulsar's nebula in a campaign comprising 11 40 ks observations with the Chandra X-Ray Observatory. The deepest images yet revealed the shape, structure, and motion of the 2 arcmin long pulsar jet. We find that the jet's shape and dynamics are remarkably consistent with those of a steadily turning helix projected on the sky. We discuss possible implications of our results, including free precession of the neutron star and MHD instability scenarios.

Durant, Martin; Kargaltsev, Oleg [University of Florida, 211 Bryant Space Science Center, Gainesville, FL (United States)] [University of Florida, 211 Bryant Space Science Center, Gainesville, FL (United States); Pavlov, George G. [Pennsylvania State University, 525 Davey Lab, University Park, PA (United States)] [Pennsylvania State University, 525 Davey Lab, University Park, PA (United States); Kropotina, Julia; Levenfish, Kseniya, E-mail: mdurant@sri.utoronto.ca [St.-Petersburg State Polytechnical University, Polytekhnicheskaya ul. 29, St.-Petersburg, 195251 (Russian Federation)] [St.-Petersburg State Polytechnical University, Polytekhnicheskaya ul. 29, St.-Petersburg, 195251 (Russian Federation)

2013-02-15T23:59:59.000Z

272

Gamma-Ray Bursts: Jets and Energetics  

E-Print Network [OSTI]

The relativistic outflows from gamma-ray bursts are now thought to be narrowly collimated into jets. After correcting for this jet geometry there is a remarkable constancy of both the energy radiated by the burst and the kinetic energy carried by the outflow. Gamma-ray bursts are still the most luminous explosions in the Universe, but they release energies that are comparable to supernovae. The diversity of cosmic explosions appears to be governed by the fraction of energy that is coupled to ultra-relativistic ejecta.

D. A. Frail

2003-11-12T23:59:59.000Z

273

Enhancement of wall jet transport properties  

DOE Patents [OSTI]

By enhancing the natural instabilities in the boundary layer and in the free shear layer of a wall jet, the boundary is minimized thereby increasing the transport of heat and mass. Enhancing the natural instabilities is accomplished by pulsing the flow of air that creates the wall jet. Such pulsing of the flow of air can be accomplished by sequentially occluding and opening a duct that confines and directs the flow of air, such as by rotating a disk on an axis transverse to the flow of air in the duct. 17 figs.

Claunch, S.D.; Farrington, R.B.

1997-02-04T23:59:59.000Z

274

High pressure water jet mining machine  

DOE Patents [OSTI]

A high pressure water jet mining machine for the longwall mining of coal is described. The machine is generally in the shape of a plowshare and is advanced in the direction in which the coal is cut. The machine has mounted thereon a plurality of nozzle modules each containing a high pressure water jet nozzle disposed to oscillate in a particular plane. The nozzle modules are oriented to cut in vertical and horizontal planes on the leading edge of the machine and the coal so cut is cleaved off by the wedge-shaped body.

Barker, Clark R. (Rolla, MO)

1981-05-05T23:59:59.000Z

275

Heavy vehicle propulsion system materials program semiannual progress report for April 1999 through September 1999  

SciTech Connect (OSTI)

The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks.

Johnson, D.R.

2000-01-01T23:59:59.000Z

276

Experimental Flash Pyrolysis of High Density1 PolyEthylene under Hybrid Propulsion Conditions2  

E-Print Network [OSTI]

1/25 Experimental Flash Pyrolysis of High Density1 PolyEthylene under Hybrid Propulsion Conditions2 Poly-Ethylene (HDPE) is studied6 up to 20 000 K.s-1 , under pressure up to 3.0 MPa and at temperature Pyrolysis (2013) 1-11" DOI : 10.1016/j.jaap.2013.02.014 #12;2/25 Keywords: Polyethylene; flash pyrolysis

Boyer, Edmond

277

Numerical models analysis of energy conversion process in air-breathing laser propulsion  

SciTech Connect (OSTI)

Energy source was considered as a key essential in this paper to describe energy conversion process in air-breathing laser propulsion. Some secondary factors were ignored when three independent modules, ray transmission module, energy source term module and fluid dynamic module, were established by simultaneous laser radiation transportation equation and fluid mechanics equation. The incidence laser beam was simulated based on ray tracing method. The calculated results were in good agreement with those of theoretical analysis and experiments.

Hong Yanji; Song Junling; Cui Cunyan; Li Qian [Academy of Equipment Command and Technology, 101416 Beijing (China)

2011-11-10T23:59:59.000Z

278

Large Eddy Simulations of Jet Flow Interactions Within Rod Bundles  

E-Print Network [OSTI]

The present work investigates the turbulent jet flow mixing of downward impinging jets within a staggered rod bundle based on previous experimental work. The two inlet jets had Reynold's numbers of 11,160 and 6,250 and were chosen to coincide...

Salpeter, Nathaniel O.

2010-07-14T23:59:59.000Z

279

An Overview of Brazilian Developments in Beamed Energy Aerospace Propulsion and Vehicle Performance Control  

SciTech Connect (OSTI)

Beamed energy propulsion and beamed energy vehicle performance control concepts are equally promising and challenging. In Brazil, the two concepts are being currently investigated at the Prof Henry T Nagamatsu Laboratory of Aerothermodynamics and Hypersonics, of the Institute for Advanced Studies--IEAv, in collaboration with the Rensselaer Polytechnic Institute--RPI, Troy, NY, and the United States Air force Research Laboratory-AFRL. Until recently, only laser energy addition for hypersonic flow control was being investigated at the Laboratory using a 0.3 m nozzle exit diameter hypersonic shock tunnel, T2, and two 7 joule CO{sub 2} TEA lasers. Flow visualization, model pressure and heat flux measurements of the laser energy addition perturbed flow around a model were produced as a result of this joint IEAv-RPI investigation. Presently, with the participation of AFRL and the newly commissioned 0.6 m. nozzle exit diameter hypersonic shock tunnel, T3, a more ambitious project is underway. Two 400 Joule Lumonics 620 CO{sub 2} TEA lasers will deliver a 20 cm X 25 cm propulsive laser beam to a complete laser propelled air breather/rocket hypersonic engine, located inside T3 test section. Schlieren photographs of the flow inside de engine as well as surface and heat flux measurements will be performed for free stream Mach numbers ranging from 6 to 25. The present paper discusses past, present and future Brazilian activities on beamed energy propulsion and related technologies.

Minucci, M. A. S. [Prof Henry T Nagamatsu Laboratory of Aerothermodynamics and Hypersonics Institute for Advanced Studies-IEAv General-Command of Aerospace Technology-CTA Sao Jose dos Campos-SP 12228-001 (Brazil)

2008-04-28T23:59:59.000Z

280

An Overview of Facilities and Capabilities to Support the Development of Nuclear Thermal Propulsion  

SciTech Connect (OSTI)

Abstract. The future of American space exploration depends on the ability to rapidly and economically access locations of interest throughout the solar system. There is a large body of work (both in the US and the Former Soviet Union) that show that Nuclear Thermal Propulsion (NTP) is the most technically mature, advanced propulsion system that can enable this rapid and economical access by its ability to provide a step increase above what is a feasible using a traditional chemical rocket system. For an NTP system to be deployed, the earlier measurements and recent predictions of the performance of the fuel and the reactor system need to be confirmed experimentally prior to launch. Major fuel and reactor system issues to be addressed include fuel performance at temperature, hydrogen compatibility, fission product retention, and restart capability. The prime issue to be addressed for reactor system performance testing involves finding an affordable and environmentally acceptable method to test a range of engine sizes using a combination of nuclear and non-nuclear test facilities. This paper provides an assessment of some of the capabilities and facilities that are available or will be needed to develop and test the nuclear fuel, and reactor components. It will also address briefly options to take advantage of the greatly improvement in computation/simulation and materials processing capabilities that would contribute to making the development of an NTP system more affordable. Keywords: Nuclear Thermal Propulsion (NTP), Fuel fabrication, nuclear testing, test facilities.

James Werner; Sam Bhattacharyya; Mike Houts

2011-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Studying Z/gamma*+Jet Production  

SciTech Connect (OSTI)

The production of jets in association with a Z/{gamma}* boson is an example of an important class of processes at hadron colliders, namely vector boson + jet (V + jet) production. Comparisons of measurements of this class of processes with theory predictions constitute an important, fundamental test of the Standard Model of particle physics, and of the theory of QCD in particular. While having a smaller cross section than other V +jet processes, Z/{gamma}*({yields} e{sup +}e{sup -}) + jets production, with Z/{gamma}* {yields} e{sup +}e{sup -}/{mu}{sup +}{mu}{sup -}, has a distinct experimental signature allowing for measurements characterized by low backgrounds and a direct, precise measurement of the properties of the decay products of the Z/{gamma}* boson. In this thesis, several new measurements of the properties of jets produced in association with a Z/{gamma}* boson in p{bar p} collisions at {radical}s = 1.96 TeV are presented. The cross section for Z/{gamma}*({yields} e{sup +}e{sup -}) + N jet production (N {le} 3) is measured, differential in the transverse momentum of the Nth jet in the event, normalized to the inclusive Z/{gamma}* cross section. Also, the cross section for Z/{gamma}*({yields} e{sup +}e{sup -}) + N jets (N {ge} 1) is measured, differential in the difference in azimuthal angle between the di-electron system and any jet in the event, normalized to unity. The data used in the measurements were collected by the D0 experiment located at the Tevatron Collider of the Fermi National Accelerator Laboratory and correspond to an integrated luminosity of 1.04 fb{sup -1}. The measured jet transverse momentum spectra are compared with the predictions of perturbative calculations at the next-to-leading order in the strong coupling constant. Given the low sensitivity of the calculations to model parameters, these comparisons represent a stringent test of perturbative QCD. One of the main goals currently being pursued in particle physics is the discovery of the only particle predicted by the Standard Model which has so far no been detected experimentally, namely the Higgs boson. It is assumed that the ATLAS and CMS experiments located at the Large Hadron Collider (LHC), a proton-proton collider at {radical}s = 14 TeV, will be able to detect the Higgs boson, or rule out its existence, within the next few years. The collisions delivered by the LHC will also be used to perform a long range of searches for other new particles, for instance particles predicted by models based on the principle of supersymmetry. The associated production of vector bosons with jets has relatively large production rates at the LHC and can produce a long list of different final states which can include charged leptons, missing transverse energy, as well as light- and heavy-flavour jets. This makes V + jet production a major source of background events to many searches for new particles. Most techniques used for estimating the expected number of background events to searches rely on passing the stable final-state particles of simulated hadron collisions generated using a so-called event generator code, through a simulation of the experimental detector system. The development of event generators which are capable of reliably predicting the properties of jets produced in association with a core process, e.g. the production of a vector boson, has been the subject of a large amount of research activity during the last ten years. These efforts have led to the appearance of the CKKW and MLM algorithms which are implemented in several event generators, among them SHERPA and ALPGEN + PYTHIA. The large data sample collected by the D0 experiment during Run II offers an excellent opportunity for validating these new event generators against experimental measurements of V + jet production. As argued above, the Z/{gamma}*({yields} e{sup +}e{sup -}) + jets process offers the combination of a clean experimental signature and large production rates, making it the process of choice for these studies.

Nilsen, Henrik Wold; /Freiburg U.

2009-07-01T23:59:59.000Z

282

Preliminary Study Using ForwardPreliminary Study Using Forward Reaction Control System JetsReaction Control System Jets  

E-Print Network [OSTI]

Preliminary Study Using ForwardPreliminary Study Using Forward Reaction Control System JetsReaction Control System Jets During Space Shuttle EntryDuring Space Shuttle Entry Carolina Restrepo Currently the shuttle uses only aft RCS jets for yaw control during entry Enough to handle present flight

Valasek, John

283

HYPERSONIC BUCKSHOT: ASTROPHYSICAL JETS AS HETEROGENEOUS COLLIMATED PLASMOIDS  

SciTech Connect (OSTI)

Herbig-Haro jets are commonly thought of as homogeneous beams of plasma traveling at hypersonic velocities. Structure within jet beams is often attributed to periodic or 'pulsed' variations of conditions at the jet source. Simulations based on this scenario result in knots extending across the jet diameter. Observations and recent high energy density laboratory experiments shed new light on structures below this scale and indicate they may be important for understanding the fundamentals of jet dynamics. In this paper, we offer an alternative to 'pulsed' models of protostellar jets. Using direct numerical simulations we explore the possibility that jets are chains of subradial clumps propagating through a moving interclump medium. Our models explore an idealization of this scenario by injecting small (r < r {sub jet}), dense ({rho}>{rho}{sub jet}) spheres embedded in an otherwise smooth interclump jet flow. The spheres are initialized with velocities differing from the jet velocity by {approx}15%. We find that the consequences of shifting from homogeneous to heterogeneous flows are significant as clumps interact with each other and with the interclump medium in a variety of ways. Structures which mimic what is expected from pulsed-jet models can form, as can be previously unseen, 'subradial' behaviors including backward facing bow shocks and off-axis working surfaces. While these small-scale structures have not been seen before in simulation studies, they are found in high-resolution jet observations. We discuss implications of our simulations for the interpretation of protostellar jets with regard to characterization of knots by a 'lifetime' or 'velocity history' approach as well as linking observed structures with central engines which produce the jets.

Yirak, Kristopher; Frank, Adam; Cunningham, Andrew J. [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14620 (United States); Mitran, Sorin [Department of Mathematics, Applied Mathematics Program, University of North Carolina, Chapel Hill, NC 27599 (United States)], E-mail: yirak@pas.rochester.edu

2009-04-20T23:59:59.000Z

284

Jet Vetoes Interfering with H->WW  

E-Print Network [OSTI]

Far off-shell Higgs production in $H \\rightarrow WW,ZZ$, is a particularly powerful probe of Higgs properties, allowing one to disentangle Higgs width and coupling information unavailable in on-shell rate measurements. These measurements require an understanding of the cross section in the far off-shell region in the presence of realistic experimental cuts. We analytically study the effect of a $p_T$ jet veto on far off-shell cross sections, including signal-background interference, by utilizing hard functions in the soft collinear effective theory that are differential in the decay products of the $W/Z$. Summing large logarithms of $\\sqrt{\\hat s}/p_T^{veto}$, we find that the jet veto induces a strong dependence on the partonic centre of mass energy, $\\sqrt{\\hat s}$, and modifies distributions in $\\sqrt{\\hat s}$ or $M_T$. The example of $gg\\rightarrow H \\rightarrow WW$ is used to demonstrate these effects at next to leading log order. We also discuss the importance of jet vetoes and jet binning for the recent program to extract Higgs couplings and widths from far off-shell cross sections.

Ian Moult; Iain W. Stewart

2014-09-08T23:59:59.000Z

285

The Rapidity Dependence of Jet Quenching  

E-Print Network [OSTI]

The suppression of high transverse momentum (P_T) jets and hadrons in ultrarelativistic heavy-ion collisions with respect to a p-p baseline in terms of the nuclear suppression factor R_AA is one of the key observables to gauge the density of a hot and dense QCD medium. However, the suppression measured by R_AA is not a straightforward measure of the medium properties, the value of the observable also depends on the ratio of quark to gluon jets and on the slope of the hard parton spectrum, which explains why R_AA is found to be fairly similar at RHIC and LHC despite the very different dynamics. Measuring high P_T jets and hadrons at forward rapidity offers the same possibility of varying medium density, parton mixture and spectral slope without the need to compare across different sqrt(s) and experiments. In this work, the well-tested jet quenching Monte-Carlo (MC) framework YaJEM is utilized to compute the rapidity dependence of R_AA for three test cases.

Thorsten Renk

2014-06-26T23:59:59.000Z

286

The interaction between two radial jets  

E-Print Network [OSTI]

on an impingement surface with high surface heat and mass transfer. The objective of this study was to characterize the flow, surface pressure, and heat transfer for two radial jets as a function of nozzle geometry, in order to be able to design arrays of radial...

Gruber, Thomas Clifton

2012-06-07T23:59:59.000Z

287

Models comparison for JET polarimeter data  

SciTech Connect (OSTI)

A complete comparison between the theory and the measurements in polarimetry was done by using the Far Infrared Polarimeter at JET. More than 300 shots were analyzed, including a wide spectrum of JET scenarios in all critical conditions for polarimetry: high density, high and very low fields, high temperatures.This work is aimed at the demonstration of the robustness of the theoretical models for the JET polarimeter measurements in the perspective of using these models for ITER like plasma scenarios . In this context, an assessment was performed on how the line-integrated plasma density along the central vertical chord of FIR polarimeter could be evaluated using the Cotton-Mouton effect and its possible concrete use to correct fringe jumps of the interferometer.The models considered are: i) the rigorous numerical solution of the Stokes propagation equations, using dielectric tensor evaluated from JET equilibrium and Thomson scattering [1,2]; ii) two types of approximated solutions [2,3] and iii) the Guenther empirical model [4] that considers the mutual effect between Cotton-Mouton and Faraday rotation angle. The model calculations have been compared with polarimeter measurements for the Cotton-Mouton phase shift.The agreement with theory is satisfactory within the limits of experimental errors [3].

Mazzotta, C.; Orsitto, F. P.; Giovannozzi, E. [Centro Ricerche Energia Frascati, Euratom-ENEA Association, Frascati (Italy); Boboc, A.; Tudisco, O.; Zabeo, L. [Association EURATOM-UKAEA Culham Science Centre Abingdon 0X14 3DB (UK) (United Kingdom); Brombin, M.; Murari, A. [Consorzio RFX, Euratom-ENEA Association, Padova (Italy)

2008-03-12T23:59:59.000Z

288

HOT ELECTROMAGNETIC OUTFLOWS. II. JET BREAKOUT  

SciTech Connect (OSTI)

We consider the interaction between radiation, matter, and a magnetic field in a compact, relativistic jet. The entrained matter accelerates outward as the jet breaks out of a star or other confining medium. In some circumstances, such as gamma-ray bursts (GRBs), the magnetization of the jet is greatly reduced by an advected radiation field while the jet is optically thick to scattering. Where magnetic flux surfaces diverge rapidly, a strong outward Lorentz force develops and radiation and matter begin to decouple. The increase in magnetization is coupled to a rapid growth in Lorentz factor. We take two approaches to this problem. The first examines the flow outside the fast magnetosonic critical surface, and calculates the flow speed and the angular distribution of the radiation field over a range of scattering depths. The second considers the flow structure on both sides of the critical surface in the optically thin regime, using a relaxation method. In both approaches, we find how the terminal Lorentz factor and radial profile of the outflow depend on the radiation intensity and optical depth at breakout. The effect of bulk Compton scattering on the radiation spectrum is calculated by a Monte Carlo method, while neglecting the effects of internal dissipation. The peak of the scattered spectrum sits near the seed peak if radiation pressure dominates the acceleration, but is pushed to a higher frequency if the Lorentz force dominates. The unscattered seed radiation can form a distinct, low-frequency component of the spectrum, especially if the magnetic Poynting flux dominates.

Russo, Matthew [Department of Physics, University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7 (Canada); Thompson, Christopher [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, ON M5S 3H8 (Canada)

2013-08-20T23:59:59.000Z

289

Dynamics, Structure, and Emission of Electron-Positron Jets  

E-Print Network [OSTI]

The theory of gamma-ray emission from e$^{\\pm}$ jets and the implications for jet formation, dynamics and structure are reviewed. In particular, possible carriers of the jet's thrust on small scales, the transition from electromagnetic to particle dominance in Poynting flux jets, formation of pair cascades, synchrotron emission by cascading pairs, and formation of shocks due to unsteadiness in the jet parameters are considered, with emphasis on the observational consequences. Some recent progress in modeling transient emission from blazars is also briefly discussed.

A. Levinson

1997-08-10T23:59:59.000Z

290

?Linear Gas Jet with Tailored Density Profile"  

SciTech Connect (OSTI)

Supersonic, highly collimated gas jets and gas-filled capillary discharge waveguides are two primary targets of choice for Laser Plasma Accelerators (LPA) . Present gas jets have lengths of only 2-4 mm at densities of 1-4E19 cm-3, sufficient for self trapping and electron acceleration to energies up to ~150 MeV. Capillary structures 3 cm long have been used to accelerate beams up to 1 GeV. Capillary discharges used in LPAs serve to guide the pump laser and optimize the energy gain. A wall-stabilized capillary discharge provides a transverse profile across the channel that helps guide the laser and combat diffraction. Gas injection via a fast nozzle at one end provides some longitudinal density control, to improve the coupling. Gas jets with uniform or controlled density profiles may be used to control electron bunch injection and are being integrated into capillary experiments to add tuning of density. The gas jet for electron injection has not yet been optimized. Our Ph-I results have provided the LPA community with an alternative path to realizing a 2-3GeV electron bunch using just a gas jet. For example, our slit/blade combination gives a 15-20mm long acceleration path with tunable density profile, serving as an alternative to a 20-mm long capillary discharge with gas injection at one end. In Ph-II, we will extend these results to longer nozzles, to see whether we can synthesize 30 or 40-mm long plasma channels for LPAs.

KRISHNAN, Mahadevan

2012-12-10T23:59:59.000Z

291

Hypersonic Buckshot: Astrophysical Jets as Heterogeneous Collimated Plasmoids  

E-Print Network [OSTI]

Herbig-Haro (HH) jets are commonly thought of as homogeneous beams of plasma traveling at hypersonic velocities. Structure within jet beams is often attributed to periodic or ``pulsed'' variations of conditions at the jet source. Simulations based on this scenario result in knots extending across the jet diameter. Observations and recent high energy density laboratory experiments shed new light on structures below this scale and indicate they may be important for understanding the fundamentals of jet dynamics. In this paper we offer an alternative to ``pulsed'' models of protostellar jets. Using direct numerical simulations we explore the possibility that jets are chains of sub-radial clumps propagating through a moving inter-clump medium. Our models explore an idealization of this scenario by injecting small ($r\\rho_{jet}$) spheres embedded in an otherwise smooth inter-clump jet flow. The spheres are initialized with velocities differing from the jet velocity by $\\sim15$%. We find the consequences of shifting from homogeneous to heterogeneous flows are significant as clumps interact with each other and with the inter-clump medium in a variety of ways. Structures which mimic what is expected from pulsed-jet models can form, as can previously unseen ``sub-radial'' behaviors including backward facing bow shocks and off-axis working surfaces. While these small-scale structures have not been seen before in simulation studies, they are found in high resolution jet observations. We discuss implications of our simulations for the interpretation of protostellar jets with regard to characterization of knots by a ``lifetime'' or ``velocity history'' approach as well as linking observed structures with central engines which produce the jets.

Kristopher Yirak; Adam Frank; Andrew J. Cunningham; Sorin Mitran

2008-05-30T23:59:59.000Z

292

Jet Propulsion Laboratory (JPL) Agency Introduction: The FY 2012 budget request for NASA is $18.7 billion, the FY 2010 enacted  

E-Print Network [OSTI]

and development for robotic exploration of space for NASA, and has a wide-ranging charter for Solar System Network, which is the communications gateway to robotic spacecraft throughout the solar system beyond garage to replace parking capacity lost when the current lease for parking space with the City

293

Experimental study of elliptical jet from sub to supercritical conditions  

SciTech Connect (OSTI)

The jet mixing at supercritical conditions involves fluid dynamics as well as thermodynamic phenomena. All the jet mixing studies at critical conditions to the present date have focused only on axisymmetric jets. When the liquid jet is injected into supercritical environment, the thermodynamic transition could be well understood by considering one of the important fluid properties such as surface tension since it decides the existence of distinct boundary between the liquid and gaseous phase. It is well known that an elliptical liquid jet undergoes axis-switching phenomena under atmospheric conditions due to the presence of surface tension. The experimental investigations were carried out with low speed elliptical jet under supercritical condition. Investigation of the binary component system with fluoroketone jet and N{sub 2} gas as environment shows that the surface tension force dominates for a large downstream distance, indicating delayed thermodynamic transition. The increase in pressure to critical state at supercritical temperature is found to expedite the thermodynamic transition. The ligament like structures has been observed rather than droplets for supercritical pressures. However, for the single component system with fluoroketone jet and fluoroketone environment shows that the jet disintegrates into droplets as it is subjected to the chamber conditions even for the subcritical pressures and no axis switching phenomenon is observed. For a single component system, as the pressure is increased to critical state, the liquid jet exhibits gas-gas like mixing behavior and that too without exhibiting axis-switching behavior.

Muthukumaran, C. K.; Vaidyanathan, Aravind, E-mail: aravind7@iist.ac.in [Department of Aerospace Engineering, Indian Institute of Space Science and Technology, Trivandrum, Kerala 695547 (India)] [Department of Aerospace Engineering, Indian Institute of Space Science and Technology, Trivandrum, Kerala 695547 (India)

2014-04-15T23:59:59.000Z

294

Leading Particle Production in Light Flavour Jets  

E-Print Network [OSTI]

The energy distribution and type of the particle with the highest momentum in quark jets are determined for each of the five quark flavours making only minimal model assumptions. The analysis is based on a large statistics sample of hadronic Z0 decays collected with the OPAL detector at the LEP e+e- collider. These results provide a basis for future studies of light flavour production at other centre-of-mass energies. We use our results to study the hadronisation mechanism in light flavour jets and compare the data to the QCD models JETSET and HERWIG. Within the JETSET model we also directly determine the suppression of strange quarks to be gamma_s=0.422+-0.049 (stat.)+-0.059 (syst.) by comparing the production of charged and neutral kaons in strange and non-strange light quark events. Finally we study the features of baryon production.

Abbiendi, G; Åkesson, P F; Alexander, Gideon; Allison, J; Anderson, K J; Arcelli, S; Asai, S; Ashby, S F; Axen, D A; Azuelos, Georges; Bailey, I; Ball, A H; Barberio, E; Barlow, R J; Batley, J Richard; Baumann, S; Behnke, T; Bell, K W; Bella, G; Bellerive, A; Bentvelsen, Stanislaus Cornelius Maria; Bethke, Siegfried; Betts, S; Biebel, O; Biguzzi, A; Bloodworth, Ian J; Bock, P; Böhme, J; Boeriu, O; Bonacorsi, D; Boutemeur, M; Braibant, S; Bright-Thomas, P G; Brigliadori, L; Brown, R M; Burckhart, Helfried J; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Chrisman, D; Ciocca, C; Clarke, P E L; Clay, E; Cohen, I; Conboy, J E; Cooke, O C; Couchman, J; Couyoumtzelis, C; Coxe, R L; Cuffiani, M; Dado, S; Dallavalle, G M; Dallison, S; Davis, R; de Roeck, A; Dervan, P J; Desch, Klaus; Dienes, B; Dixit, M S; Donkers, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Estabrooks, P G; Etzion, E; Fabbri, Franco Luigi; Fanfani, A; Fanti, M; Faust, A A; Feld, L; Ferrari, P; Fiedler, F; Fierro, M; Fleck, I; Frey, A; Fürtjes, A; Futyan, D I; Gagnon, P; Gary, J W; Gaycken, G; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Gingrich, D M; Glenzinski, D A; Goldberg, J; Gorn, W; Grandi, C; Graham, K; Gross, E; Grunhaus, Jacob; Gruwé, M; Hajdu, C; Hanson, G G; Hansroul, M; Hapke, M; Harder, K; Harel, A; Hargrove, C K; Harin-Dirac, M; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, Richard J; Herten, G; Heuer, R D; Hildreth, M D; Hill, J C; Hobson, P R; Höcker, Andreas; Hoffman, K; Homer, R James; Honma, A K; Horváth, D; Hossain, K R; Howard, R; Hüntemeyer, P; Igo-Kemenes, P; Imrie, D C; Ishii, K; Jacob, F R; Jawahery, A; Jeremie, H; Jimack, Martin Paul; Jones, C R; Jovanovic, P; Junk, T R; Kanaya, N; Kanzaki, J I; Karapetian, G V; Karlen, D A; Kartvelishvili, V G; Kawagoe, K; Kawamoto, T; Kayal, P I; Keeler, Richard K; Kellogg, R G; Kennedy, B W; Kim, D H; Klier, A; Kobayashi, T; Kobel, M; Kokott, T P; Kolrep, M; Komamiya, S; Kowalewski, R V; Kress, T; Krieger, P; Von Krogh, J; Kühl, T; Kupper, M; Kyberd, P; Lafferty, G D; Landsman, Hagar Yaël; Lanske, D; Lauber, J; Lawson, I; Layter, J G; Lellouch, Daniel; Letts, J; Levinson, L; Liebisch, R; Lillich, J; List, B; Littlewood, C; Lloyd, A W; Lloyd, S L; Loebinger, F K; Long, G D; Losty, Michael J; Lü, J; Ludwig, J; Macchiolo, A; MacPherson, A L; Mader, W F; Mannelli, M; Marcellini, S; Marchant, T E; Martin, A J; Martin, J P; Martínez, G; Mashimo, T; Mättig, P; McDonald, W J; McKenna, J A; McKigney, E A; McMahon, T J; McPherson, R A; Meijers, F; Méndez-Lorenzo, P; Merritt, F S; Mes, H; Meyer, I; Michelini, Aldo; Mihara, S; Mikenberg, G; Miller, D J; Mohr, W; Montanari, A; Mori, T; Nagai, K; Nakamura, I; Neal, H A; Nisius, R; O'Neale, S W; Oakham, F G; Odorici, F; Ögren, H O; Okpara, A N; Oreglia, M J; Orito, S; Pásztor, G; Pater, J R; Patrick, G N; Patt, J; Pérez-Ochoa, R; Petzold, S; Pfeifenschneider, P; Pilcher, J E; Pinfold, James L; Plane, D E; Poli, B; Polok, J; Przybycien, M B; Quadt, A; Rembser, C; Rick, Hartmut; Robins, S A; Rodning, N L; Roney, J M; Rosati, S; Roscoe, K; Rossi, A M; Rozen, Y; Runge, K; Runólfsson, O; Rust, D R; Sachs, K; Saeki, T; Sahr, O; Sang, W M; Sarkisyan-Grinbaum, E; Sbarra, C; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schieck, J; Schmitt, S; Schöning, A; Schröder, M; Schumacher, M; Schwick, C; Scott, W G; Seuster, R; Shears, T G; Shen, B C; Shepherd-Themistocleous, C H; Sherwood, P; Siroli, G P; Skuja, A; Smith, A M; Snow, G A; Sobie, Randall J; Söldner-Rembold, S; Spagnolo, S; Sproston, M; Stahl, A; Stephens, K; Stoll, K; Strom, D; Ströhmer, R; Surrow, B; Talbot, S D; Taras, P; Tarem, S; Teuscher, R; Thiergen, M; Thomas, J; Thomson, M A; Torrence, E; Towers, S; Trefzger, T M; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Van Kooten, R; Vannerem, P; Verzocchi, M; Voss, H; Wäckerle, F; Waller, D; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wetterling, D; White, J S; Wilson, G W; Wilson, J A; Wyatt, T R; Yamashita, S; Zacek, V; Zer-Zion, D

2000-01-01T23:59:59.000Z

295

Phenomenology of Gamma-Ray Jets  

E-Print Network [OSTI]

We discuss some phenomenological aspects of $\\gamma$-ray emitting jets. In particular, we present calculations of the $\\gamma$-sphere and $\\pi$-sphere for various target photon fields, and employ them to demonstrate how $\\gamma$-ray observations at very high energies can be used to constraint the Doppler factor of the emitting plasma and the production of VHE neutrinos. We also consider the implications of the rapid TeV variability observed in M87 and the TeV blazars, and propose a model for the very rapid TeV flares observed with HESS and MAGIC in some blazars,that accommodates the relatively small Doppler factors inferred from radio observations. Finally, we briefly discuss the prospects for detecting VHE neutrinos from relativistic jets.

Amir Levinson

2007-09-10T23:59:59.000Z

296

Dense, vertical jet in stagnant homogeneous fluid  

E-Print Network [OSTI]

30. 4 53. 2 76. 0 21. 5 37. 6 53. 7 17. 5 30. 7 41. 6 3. 1 5. 4 7. 7 G. l 10. 0 15. 4 9. 2 16. 1 21. 9 0. 16 0. 28 0. 40 0. 65 1. 13 l. 62 1. 46 2. 55 3 45 H/D 50. 0 50. 0 50. 0 25. 0 25. 0 25. 0 16. 7 16, 7 16. 7...) m D 120 80 1 m D d Jet Height(from the nozzle) Abraham Jet or nozzle diameter (slope = 1. 94) Riser height H/d 0 5 r liater depth(Tank depth) (slope 1 89) L4 ft. (1. 22 m. )] s 0 pe' H/d = 0. 333 I +Turner (slope = 1. 82) ~~ ~ (slope...

Vergara, Ignacio

2012-06-07T23:59:59.000Z

297

Azimuthal Jet Tomography at RHIC and LHC  

E-Print Network [OSTI]

A generic jet-energy loss model that is coupled to state-of-the-art hydrodynamic fields and interpolates between a wide class of running coupling pQCD-based and AdS/CFT-inspired models is compared to recent data on the azimuthal and transverse momentum dependence of high-pT pion nuclear modification factors and high-pT elliptic flow measured at RHIC and LHC. We find that RHIC data are surprisingly consistent with various scenarios considered. However, extrapolations to LHC energies favor running coupling pQCD-based models of jet-energy loss. While conformal holographic models are shown to be inconsistent with data, recent non-conformal generalizations of AdS holography may provide an alternative description.

Barbara Betz; Miklos Gyulassy

2014-02-14T23:59:59.000Z

298

Cryogenic target formation using cold gas jets  

DOE Patents [OSTI]

A method and apparatus using cold gas jets for producing a substantially uniform layer of cryogenic materials on the inner surface of hollow spherical members having one or more layers, such as inertially imploded targets are disclosed. By vaporizing and quickly refreezing cryogenic materials contained within a hollow spherical member, a uniform layer of the materials is formed on an inner surface of the spherical member. Basically the method involves directing cold gas jets onto a spherical member having one or more layers or shells and containing the cryogenic material, such as a deuterium-tritium (DT) mixture, to freeze the contained material, momentarily heating the spherical member so as to vaporize the contained material, and quickly refreezing the thus vaporized material forming a uniform layer of cryogenic material on an inner surface of the spherical member. 4 figs.

Hendricks, C.D.

1980-02-26T23:59:59.000Z

299

Cryogenic target formation using cold gas jets  

DOE Patents [OSTI]

A method and apparatus using cold gas jets for producing a substantially uniform layer of cryogenic materials on the inner surface of hollow spherical members having one or more layers, such as inertially imploded targets. By vaporizing and quickly refreezing cryogenic materials contained within a hollow spherical member, a uniform layer of the materials is formed on an inner surface of the spherical member. Basically the method involves directing cold gas jets onto a spherical member having one or more layers or shells and containing the cryogenic material, such as a deuterium-tritium (DT) mixture, to freeze the contained material, momentarily heating the spherical member so as to vaporize the contained material, and quickly refreezing the thus vaporized material forming a uniform layer of cryogenic material on an inner surface of the spherical member.

Hendricks, Charles D. [Livermore, CA

1980-02-26T23:59:59.000Z

300

Space Nuclear Power and Propulsion - a basic Tool for the manned Exploration of the Solar System  

SciTech Connect (OSTI)

Humanity has started to explore space more than 40 years ago. Numerous spacecraft have left the Earth in this endeavour, but while unmanned spacecraft were already sent out on missions, where they would eventually reach the outer limits of the Solar System, manned exploration has always been confined to the tiny bubble of the Earth's gravitational well, stretching out at maximum to our closest celestial companion - the Moon - during the era of the Apollo programme in the late 60's and early 70's. When mankind made its giant leap, the exploration of our cosmic neighbour was seen as the initial step for the manned exploration of the whole Solar System. Consequently ambitious research and development programmes were undertaken at that time to enable what seemed to be the next logical steps: the establishment of a permanent settled base on the Moon and the first manned mission to Mars in the 80's. Nuclear space power and propulsion played an important role in these entire future scenarios, hence ambitious development programmes were undertaken to make these technologies available. Unfortunately the 70's-paradigm shift in space policies did not only bring an end to the Apollo programme, but it also brought a complete halt to all of these technology programmes and confined the human presence in space to a tiny bubble including nothing more than the Earth's sphere and a mere shell of a few hundred kilometres of altitude, too small to even include the Moon. Today, after more than three decades, manned exploration of the Solar System has become an issue again and so are missions to Moon and Mars. However, studies and analyses show that all of these future plans are hampered by today's available propulsion systems and by the problematic of solar power generation at distances at and beyond of Mars, a problem, however, that can readily be solved by the utilisation of space nuclear reactors and propulsion systems. This paper intends to provide an overview on the various fission- and fusion-based Nuclear Power and Propulsion system concepts and tries to compare these systems' different working principles and technical implementations with each other. The overview and comparison will be complemented by a closer look at ongoing activities related to research and development in this area and by an outlook on what kind of systems might be employed to carry the first astronauts to Mars and beyond. (autho0008.

Frischauf, Norbert; Hamilton, Booz Allen [ESA/ESTEC, Keplerlaan 1, P.O. Box 29, NL-2200 AG Noordwijk (Netherlands)

2004-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Flow control via synthetic jet actuation  

E-Print Network [OSTI]

4.1 Wind Tunnel Model Showing SJA Drive Through Acrylic Access Panel ..........41 4.2 Cross Section of Trailing Edge Showing Original Plenum Design .....................41 4.3 Cross Section of Trailing Edge Showing Narrow Plenum Design.... ...........................................................48 1 1. INTRODUCTION General This thesis presents a study of the effects of flow control on a NACA0015 airfoil using Synthetic Jet Actuators (SJA) at different locations along the chord. The purpose of this research was to show...

Miller, Adam Cole

2005-02-17T23:59:59.000Z

302

NLO QCD Predictions for W+3 jets  

SciTech Connect (OSTI)

In this contribution we present results from the NLO computation of the production of a W boson in association with three jets in hadronic collisions. The results are obtained by combining two programs: BlackHat for the virtual one-loop matrix elements and Sherpa for the real-emission contributions. We present results for the Tevatron and the LHC, and address the issue of the choice of a common factorization and renormalization scale for this process.

Maitre, Daniel; /Durham U.; Berger, Carola F.; /MIT; Bern, Zvi; Febres Cordero, Fernando; Ita, Harald; Dixon, Lance J.; Forde, Darren; Gleisberg, Tanju; /UCLA /SLAC; Kosower, David; /Saclay, SPhT

2009-12-09T23:59:59.000Z

303

ON THE ORIGIN OF INTERGRANULAR JETS  

SciTech Connect (OSTI)

We observe that intergranular jets, originating in the intergranular space surrounding individual granules, tend to be associated with granular fragmentation, in particular, with the formation and evolution of a bright granular lane (BGL) within individual granules. The BGLs have recently been identified as vortex tubes by Steiner et al. We further discover the development of a well-defined bright grain located between the BGL and the dark intergranular lane to which it is connected. Signatures of a BGL may reach the lower chromosphere and can be detected in off-band H{alpha} images. Simulations also indicate that vortex tubes are frequently associated with small-scale magnetic fields. We speculate that the intergranular jets detected in the New Solar Telescope (NST) data may result from the interaction between the turbulent small-scale fields associated with the vortex tube and the larger-scale fields existing in the intergranular lanes. The intergranular jets are much smaller and weaker than all previously known jet-like events. At the same time, they appear much more numerous than the larger events, leading us to the speculation that the total energy release and mass transport by these tiny events may not be negligible in the energy and mass-flux balance near the temperature minimum atop the photosphere. The study is based on the photospheric TiO broadband (1.0 nm) filter data acquired with the 1.6 m NST operating at the Big Bear Solar Observatory. The data set also includes NST off-band H{alpha} images collected through a Zeiss Lyot filter with a passband of 0.025 nm.

Yurchyshyn, V. B.; Goode, P. R.; Abramenko, V. I. [Big Bear Solar Observatory, New Jersey Institute of Technology, Big Bear City, CA 92314 (United States); Steiner, O. [Kiepenheuer-Institut fuer Sonnenphysik, Schoeneckstrasse 6, D-79104 Freiburg (Germany)

2011-08-01T23:59:59.000Z

304

Studies of Relativistic Jets in Active Galactic Nuclei with SKA  

E-Print Network [OSTI]

Relativistic jets in active galactic nuclei (AGN) are among the most powerful astrophysical objects discovered to date. Indeed, jetted AGN studies have been considered a prominent science case for SKA, and were included in several different chapters of the previous SKA Science Book (Carilli & Rawlings 2004). Most of the fundamental questions about the physics of relativistic jets still remain unanswered, and await high-sensitivity radio instruments such as SKA to solve them. These questions will be addressed specially through analysis of the massive data sets arising from the deep, all-sky surveys (both total and polarimetric flux) from SKA1. Wide-field very-long-baseline-interferometric survey observations involving SKA1 will serve as a unique tool for distinguishing between extragalactic relativistic jets and star forming galaxies via brightness temperature measurements. Subsequent SKA1 studies of relativistic jets at different resolutions will allow for unprecedented cosmological studies of AGN jets up...

Agudo, Ivan; Falcke, Heino; Georganopoulos, Markos; Ghisellini, Gabriele; Giovannini, Gabriele; Giroletti, Marcello; Gomez, Jose L; Gurvits, Leonid; Laing, Robert; Lister, Matthew; Marti, Jose-Maria; Meyer, Eileen T; Mizuno, Yosuke; O'Sullivan, Shane; Padovani, Paolo; Paragi, Zsolt; Perucho, Manel; Schleicher, Dominik; Stawarz, Lukasz; Vlahakis, Nektarios; Wardle, John

2015-01-01T23:59:59.000Z

305

JOURNAL OF PROPULSION AND POWER Vol. 21, No. 1, JanuaryFebruary 2005  

E-Print Network [OSTI]

-Pressure Turbine Main-/Secondary-Air System Flow Interaction Roger L. Davis University of California, Davis, Davis Global Research Center, Niskayuna, New York 12309 and Roger Paolillo§ and Om P. Sharma¶ Pratt and Whitney flowpath of a modern jet engine transonic high- pressure turbine, transition duct, and first vane

Alonso, Juan J.

306

MEASURING THE JET POWER OF FLAT-SPECTRUM RADIO QUASARS  

SciTech Connect (OSTI)

We use frequency-dependent position shifts of flat-spectrum radio cores to estimate the kinetic power of active galactic nucleus (AGN) jets. We find a correlation between the derived jet powers and AGN narrow-line luminosity, consistent with the well-known relation for radio galaxies and steep spectrum quasars. This technique can be applied to intrinsically weak jets even at high redshift.

Shabala, S. S.; Santoso, J. S. [School of Mathematics and Physics, University of Tasmania, Private Bag 37, Hobart, TAS 7001 (Australia); Godfrey, L. E. H. [International Centre for Radio Astronomy Research, Curtin University, GPO Box U1987, Perth, Western Australia 6845 (Australia)

2012-09-10T23:59:59.000Z

307

CONTROL OF COHERENT STRUCTURE IN COAXIAL SWIRLING TURBULENT JETS  

E-Print Network [OSTI]

.............................................................. 193 xvi NOMENCLATURE Symbol Description Unit D Jet diameter, Defined in Figure 5.1 m D h Hydraulic jet diameter m f Excitation frequency s -1 G Degree of swirl, Defined... stronger effect than the pilot jet itself, leading to an almost entire removal of coherent structures. 2.2. Flow Instability Swirl is naturally presented in the exhaust from a turbine or an axial flow pump, and may be deliberately generated...

Lee, Wonjoong

2008-01-01T23:59:59.000Z

308

Propulsion Materials  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department ofT ib l L dDepartment of Energy 0 DOE VehicleProposed agenda379632 of

309

New Opportunities for Outer Solar System Science using Radioisotope Electric Propulsion  

SciTech Connect (OSTI)

Today, our questions and hypotheses about the Solar System's origin have surpassed our ability to deliver scientific instruments to deep space. The moons of the outer planets, the Trojan and Centaur minor planets, the trans-Neptunian objects (TNO), and distant Kuiper Belt objects (KBO) hold a wealth of information about the primordial conditions that led to the formation of our Solar System. Robotic missions to these objects are needed to make the discoveries, but the lack of deep-space propulsion is impeding this science. Radioisotope electric propulsion (REP) will revolutionize the way we do deep-space planetary science with robotic vehicles, giving them unprecedented mobility. Radioisotope electric generators and lightweight ion thrusters are being developed today which will make possible REP systems with specific power in the range of 5 to 10 W/kg. Studies have shown that this specific power range is sufficient to perform fast rendezvous missions from Earth to the outer Solar System and fast sample return missions. This whitepaper discusses how mobility provided by REP opens up entirely new science opportunities for robotic missions to distant primitive bodies. We also give an overview of REP technology developments and the required next steps to realize REP.

Noble, Robert J.; /SLAC; Amini, Rashied; Beauchamp, Patricia M.; /Caltech, JPL; Bennett, Gary L.; /Metaspace Enterprises; Brophy, John R.; Buratti, Bonnie J.; Ervin, Joan; /Caltech, JPL; Fernandez, Yan R.; /Central Florida U.; Grundy, Will; /Lowell Observ.; Khan, Mohammed Omair; /Caltech, JPL; King, David Q.; /Aerojet; Lang, Jared; /Caltech, JPL; Meech, Karen J.; /Hawaii U.; Newhouse, Alan; Oleson, Steven R.; Schmidt, George R.; /GRC; Spilker, Thomas; West, John L.; /Caltech, JPL; ,

2010-05-26T23:59:59.000Z

310

System for propulsion of boats by means of winds and streams and for recovery of energy  

SciTech Connect (OSTI)

The invention relates to an improved system for propulsion of boats by winds and streams and for recovery of disposable energy from floating stations neither moored nor anchored, the improved system comprising: at least one aerial feathered propeller with its shaft, the propeller being mounted orientable in any azimuth direction contained in a substantially horizontal plane and adapted to function as an aerogenerator as well as a propulsive screw; a superstructure supporting device on the floating unit adapted to permit orientation as desired of the aerial propeller in the direction of the wind; at least one nautic propeller screw with its shaft, mounted under the bottom of the floating unit and adapted to be capable of functioning as energy collecting turbine as well as propeller; a transmission system connecting the aerial propeller shaft to the nautic propeller shaft, the transmission being reversible and capable of including a torque conversion device to select during operations the direction of transmission as well as the transmission ratio; a directional device adapted to ensure the steering of the floating unit; and control devices comprising actuating apparatus adapted to allow the driver to act, in addition upon the directional device and the azimuth orientation of said aerial propeller, upon at least two of three variable parameters of said system, namely the pitch of said aerial propeller, the transmission ratio and the pitch of said nautic propeller, by the actuating apparatus.

Vidal, J.

1983-02-01T23:59:59.000Z

311

Heavy vehicle propulsion system materials program semiannual progress report for April 1998 thru September 1998  

SciTech Connect (OSTI)

The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1--3 trucks to realize a 35{percent} fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7--8 trucks. The Office of Transportation Technologies, Office of Heavy Vehicle Technologies (OTT OHVT) has an active program to develop the technology for advanced LE-55 diesel engines with 55{percent} efficiency and low emissions levels of 2.0 g/bhp-h NO{sub x} and 0.05 g/bhp-h particulates. The goal is also for the LE-55 engine to run on natural gas with efficiency approaching that of diesel fuel. The LE-55 program is being completed in FY 1997 and, after approximately 10 years of effort, has largely met the program goals of 55{percent} efficiency and low emissions. However, the commercialization of the LE-55 technology requires more durable materials than those that have been used to demonstrate the goals. Heavy Vehicle Propulsion System Materials will, in concert with the heavy-duty diesel engine companies, develop the durable materials required to commercialize the LE-55 technologies.

Johnson, D.R.

1999-01-01T23:59:59.000Z

312

Mars mission opportunity and transit time sensitivity for a nuclear thermal rocket propulsion application  

SciTech Connect (OSTI)

President George Bush's 1989 challenge to America to support the Space Exploration Initiative (SEI) of Back to the Moon and Human Mission to Mars'' gives the space industry an opportunity to develop effective and efficient space transportation systems. This paper presents stage performance and requirements for a nuclear thermal rocket (NTR) Mars transportation system to support the human Mars mission of the SEI. Two classes of Mars mission profiles are considered in developing the NTR propulsion vehicle performance and requirements. The two Mars mission classes include the opposition class and conjunction class. The opposition class mission is associated with relatively short Mars stay times ranging from 30 to 90 days and total mission duration of 350 to 600 days. The conjunction class mission is associated with much longer Mars stay times ranging from 500 to 600 days and total mission durations of 875 to 1,000 days. Vehicle mass scaling equations are used to determine the NTR stage mass, size, and performance range required for different Mars mission opportunities and for different Mars mission durations. Mission opportunities considered include launch years 2010 to 2018. The 2010 opportunity is the most demanding launch opportunity and the 2018 opportunity is the least demanding opportunity. NTR vehicle mass and size sensitivity to NTR engine thrust level, engine specific impulse, NTR engine thrust-to-weight ratio, and Mars surface payload are presented. NTR propulsion parameter ranges include those associated with NERVA, particle bed reactor (PBR), low-pressure, and ceramic-metal-type engine design.

Young, A.C.; Mulqueen, J.A.; Nishimuta, E.L.; Emrich, W.J. (George C. Marshall Space Flight Center, Marshall Space Flight Center, Alabama 35812 (United States))

1993-01-10T23:59:59.000Z

313

Tail Emission of Prompt Gamma-Ray Burst Jets  

E-Print Network [OSTI]

Tail emission of the prompt gamma-ray burst is discussed using a multiple emitting sub-shell (inhomogeneous jet, sub-jets) model. The tail is a superposition of a number of smooth, long-duration, dim, and soft pulses emitted by segments located far from the line of sight. We find that the behavior of the tail is not so much affected by the local inhomogeneity but affected by the global sub-jet distribution. Some observed tails may disfavor the power-law jets.

Yamazaki, R; Ioka, K; Nakamura, T; Yamazaki, Ryo; Toma, Kenji; Ioka, Kunihito; Nakamura, Takashi

2006-01-01T23:59:59.000Z

314

High Multiplicity Searches at the LHC Using Jet Masses  

SciTech Connect (OSTI)

This article introduces a new class of searches for physics beyond the Standard Model that improves the sensitivity to signals with high jet multiplicity. The proposed searches gain access to high multiplicity signals by reclustering events into large-radius, or 'fat', jets and by requiring that each event has multiple massive jets. This technique is applied to supersymmetric scenarios in which gluinos are pair-produced and then subsequently decay to final states with either moderate quantities of missing energy or final states without missing energy. In each of these scenarios, the use of jet mass improves the estimated reach in gluino mass by 20% to 50% over current LHC searches.

Hook, Anson; /SLAC /Stanford U., Appl. Phys. Dept.; Izaguirre, Eder; /SLAC /Stanford U., Phys. Dept.; Lisanti, Mariangela; /Princeton U.; Wacker, Jay G.; /SLAC /Stanford U., ITP

2012-04-24T23:59:59.000Z

315

An experimental study of jet impingement on a circular cylinder  

E-Print Network [OSTI]

diameter of 6 5/8 inches. The jet was impinged upon the cylinder at nozzle distances of 7, 15, and 30 nozzle diameters, and at velocities of' 400 and 500 ft/s. The free jet was studied and found to be "typical" by comparing it to earlier studies done... Instrumentation schematic 17 5 Cylindrical suriace coordinate system 22 6 Photograph of the cylinder with "grid" 23 7 Photograph of the wall jet traversing apparatus 24 8 Orientation of the hot film sensor 25 9 Free jet geometry and parameters 30 10 Velocity...

Potts, Dennis Wayne

2012-06-07T23:59:59.000Z

316

Parsec-Scale Jet-Environment Interactions in AGN  

E-Print Network [OSTI]

Observations made with the VLBA have led to fundamental advances in our understanding of how radio jets in AGN evolve from parsec-scales out to distances exceeding several hundred kiloparsecs. In this review I discuss current models of young radio source evolution, as well as the observational evidence for a rapid change in jet properties on scales of ~1 kpc. A central topic of current debate is the relative importance of intermittent jet fueling versus jet-environment interactions in causing a drop-off in powerful radio sources at this critical evolutionary stage. Recent 3-D hydrodynamical jet simulations suggest that dense environments and cloud collisions can temporarily stifle, but not completely halt powerful relativistic jets. Several VLBA studies of jet-ISM interactions in both blazars and weak Seyfert jets have indicated that collimated outflows are indeed possible in dense environments. At present, the bulk of the evidence favors intermittent AGN accretion as the dominant factor in determining the evolutionary path of large numbers of AGN jets.

Matthew L. Lister

2007-07-12T23:59:59.000Z

317

Infrared imaging results of an excited planar jet  

SciTech Connect (OSTI)

Planar jets are used for many applications including heating, cooling, and ventilation. Generally such a jet is designed to provide good mixing within an enclosure. In building applications, the jet provides both thermal comfort and adequate indoor air quality. Increased mixing rates may lead to lower short-circuiting of conditioned air, elimination of dead zones within the occupied zone, reduced energy costs, increased occupant comfort, and higher indoor air quality. This paper discusses using an infrared imaging system to show the effect of excitation of a jet on the spread angle and on the jet mixing efficiency. Infrared imaging captures a large number of data points in real time (over 50,000 data points per image) providing significant advantages over single-point measurements. We used a screen mesh with a time constant of approximately 0.3 seconds as a target for the infrared camera to detect temperature variations in the jet. The infrared images show increased jet spread due to excitation of the jet. Digital data reduction and analysis show change in jet isotherms and quantify the increased mixing caused by excitation. 17 refs., 20 figs.

Farrington, R.B.

1991-12-01T23:59:59.000Z

318

Environmental and economic assessment of microalgae-derived jet fuel  

E-Print Network [OSTI]

Significant efforts must be undertaken to quantitatively assess various alternative jet fuel pathways when working towards achieving environmental and economic United States commercial and military alternative aviation ...

Carter, Nicholas Aaron

2012-01-01T23:59:59.000Z

319

Inclusive-jet photoproduction at HERA and determination of alphas  

E-Print Network [OSTI]

Inclusive-jet cross sections have been measured in the reaction ep->e+jet+X for photon virtuality Q2 energies in the region 142 energy, ETjet, and pseudorapidity, etajet, for jets with ETjet > 17 GeV and -1 energy-scale dependence of the coupling was determined. The value of alphas(Mz) extracted from the measurements based on the kT jet algorithm is alphas(Mz) = 0.1206 +0.0023 -0.0022 (exp.) +0.0042 -0.0035 (th.); the results from the anti-kT and SIScone algorithms are compatible with this value and have a similar precision.

ZEUS Collaboration; H. Abramowicz; I. Abt; L. Adamczyk; M. Adamus; R. Aggarwal; S. Antonelli; P. Antonioli; A. Antonov; M. Arneodo; V. Aushev; Y. Aushev; O. Bachynska; A. Bamberger; A. N. Barakbaev; G. Barbagli; G. Bari; F. Barreiro; N. Bartosik; D. Bartsch; M. Basile; O. Behnke; J. Behr; U. Behrens; L. Bellagamba; A. Bertolin; S. Bhadra; M. Bindi; C. Blohm; V. Bokhonov; T. Bold; K. Bondarenko; E. G. Boos; K. Borras; D. Boscherini; D. Bot; I. Brock; E. Brownson; R. Brugnera; N. Brummer; A. Bruni; G. Bruni; B. Brzozowska; P. J. Bussey; B. Bylsma; A. Caldwell; M. Capua; R. Carlin; C. D. Catterall; S. Chekanov; J. Chwastowski; J. Ciborowski; R. Ciesielski; L. Cifarelli; F. Cindolo; A. Contin; A. M. Cooper-Sarkar; N. Coppola; M. Corradi; F. Corriveau; M. Costa; G. D'Agostini; F. Dal Corso; J. del Peso; R. K. Dementiev; S. De Pasquale; M. Derrick; R. C. E. Devenish; D. Dobur; B. A. Dolgoshein; G. Dolinska; A. T. Doyle; V. Drugakov; L. S. Durkin; S. Dusini; Y. Eisenberg; P. F. Ermolov; A. Eskreys; S. Fang; S. Fazio; J. Ferrando; M. I. Ferrero; J. Figiel; M. Forrest; B. Foster; G. Gach; A. Galas; E. Gallo; A. Garfagnini; A. Geiser; I. Gialas; A. Gizhko; L. K. Gladilin; D. Gladkov; C. Glasman; O. Gogota; Yu. A. Golubkov; P. Gottlicher; I. Grabowska-Bold; J. Grebenyuk; I. Gregor; G. Grigorescu; G. Grzelak; O. Gueta; M. Guzik; C. Gwenlan; T. Haas; W. Hain; R. Hamatsu; J. C. Hart; H. Hartmann; G. Hartner; E. Hilger; D. Hochman; R. Hori; K. Horton; A. Huttmann; Z. A. Ibrahim; Y. Iga; R. Ingbir; M. Ishitsuka; H. -P. Jakob; F. Januschek; T. W. Jones; M. Jungst; I. Kadenko; B. Kahle; S. Kananov; T. Kanno; U. Karshon; F. Karstens; I. I. Katkov; M. Kaur; P. Kaur; A. Keramidas; L. A. Khein; J. Y. Kim; D. Kisielewska; S. Kitamura; R. Klanner; U. Klein; E. Koffeman; N. Kondrashova; O. Kononeko; P. Kooijman; Ie. Korol; I. A. Korzhavina; A. Kotanski; U. Kotz; H. Kowalski; O. Kuprash; M. Kuze; A. Lee; B. B. Levchenko; A. Levy; V. Libov; S. Limentani; T. Y. Ling; M. Lisovyi; E. Lobodzinska; W. Lohmann; B. Lohr; E. Lohrmann; K. R. Long; A. Longhin; D. Lontkovskyi; O. Yu. Lukina; J. Maeda; S. Magill; I. Makarenko; J. Malka; R. Mankel; A. Margotti; G. Marini; J. F. Martin; A. Mastroberardino; M. C. K. Mattingly; I. -A. Melzer-Pellmann; S. Mergelmeyer; S. Miglioranzi; F. Mohamad Idris; V. Monaco; A. Montanari; J. D. Morris; K. Mujkic; B. Musgrave; K. Nagano; T. Namsoo; R. Nania; A. Nigro; Y. Ning; T. Nobe; U. Noor; D. Notz; R. J. Nowak; A. E. Nuncio-Quiroz; B. Y. Oh; N. Okazaki; K. Oliver; K. Olkiewicz; Yu. Onishchuk; K. Papageorgiu; A. Parenti; E. Paul; J. M. Pawlak; B. Pawlik; P. G. Pelfer; A. Pellegrino; W. Perlanski; H. Perrey; K. Piotrzkowski; P. Plucinski; N. S. Pokrovskiy; A. Polini; A. S. Proskuryakov; M. Przybycien; A. Raval; D. D. Reeder; B. Reisert; Z. Ren; J. Repond; Y. D. Ri; A. Robertson; P. Roloff; I. Rubinsky; M. Ruspa; R. Sacchi; U. Samson; G. Sartorelli; A. A. Savin; D. H. Saxon; M. Schioppa; S. Schlenstedt; P. Schleper; W. B. Schmidke; U. Schneekloth; V. Schonberg; T. Schorner-Sadenius; J. Schwartz; F. Sciulli; L. M. Shcheglova; R. Shehzadi; S. Shimizu; I. Singh; I. O. Skillicorn; W. Slominski; W. H. Smith; V. Sola; A. Solano; D. Son; V. Sosnovtsev; A. Spiridonov; H. Stadie; L. Stanco; N. Stefaniuk; A. Stern; T. P. Stewart; A. Stifutkin; P. Stopa; S. Suchkov; G. Susinno; L. Suszycki; J. Sztuk-Dambietz; D. Szuba; J. Szuba; A. D. Tapper; E. Tassi; J. Terron; T. Theedt; H. Tiecke; K. Tokushuku; J. Tomaszewska; V. Trusov; T. Tsurugai; M. Turcato; O. Turkot; T. Tymieniecka; M. Vazquez; A. Verbytskyi; O. Viazlo; N. N. Vlasov; R. Walczak; W. A. T. Wan Abdullah; J. J. Whitmore; L. Wiggers; M. Wing; M. Wlasenko; G. Wolf; H. Wolfe; K. Wrona; A. G. Yagues-Molina; S. Yamada; Y. Yamazaki; R. Yoshida; C. Youngman; O. Zabiegalov; A. F. Zarnecki; L. Zawiejski; O. Zenaiev; W. Zeuner; B. O. Zhautykov; N. Zhmak; C. Zhou; A. Zichichi; Z. Zolkapli; D. S. Zotkin

2012-05-28T23:59:59.000Z

320

Microhole Arrays Drilled With Advanced Abrasive Slurry Jet Technology...  

Open Energy Info (EERE)

Arrays Drilled With Advanced Abrasive Slurry Jet Technology To Efficiently Exploit Enhanced Geothermal Systems Geothermal Project Jump to: navigation, search Last modified on July...

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

An alternative model of jet suppression at RHIC energies  

E-Print Network [OSTI]

We propose a simple Glauber-type mechanism for suppression of jet production up to transverse momenta of about 10 GeV/c at RHIC. For processes in this kinematic region, the formation time is smaller than the interval between two successive hard partonic collisions and the subsequent collision influences the jet production. Number of jets then roughly scales with the number of participants. Proportionality to the number of binary collisions is recovered for very high transverse momenta. The model predicts suppression of jet production in d+Au collisions at RHIC.

Roman Lietava; Jan Pisut; Neva Pisutova; Boris Tomasik

2003-02-10T23:59:59.000Z

322

Geographic Area Month Aviation Gasoline Kerosene-Type Jet Fuel  

Gasoline and Diesel Fuel Update (EIA)

State (Cents per Gallon Excluding Taxes) - Continued Geographic Area Month Aviation Gasoline Kerosene-Type Jet Fuel Kerosene Sales to End Users Sales for Resale Sales to End...

323

COLLIMATION AND CONFINEMENT OF MAGNETIC JETS BY EXTERNAL MEDIA  

SciTech Connect (OSTI)

We study the collimation of a highly magnetized jet by a surrounding cocoon that forms as a result of the interaction of the jet with the external medium. We show that in regions where the jet is well confined by the cocoon, current-driven instabilities should develop over timescales shorter than the expansion time of the jet's head. We speculate that these instabilities would give rise to complete magnetic field destruction, whereby the jet undergoes a transition from high to low sigma above the collimation zone. Using this assumption, we construct a self-consistent model for the evolution of the jet-cocoon system in an ambient medium of arbitrary density profile. We apply the model to jet breakout in long gamma-ray bursts (GRBs) and show that the jet is highly collimated inside the envelope of the progenitor star and is likely to remain confined well after breakout. We speculate that this strong confinement may provide a channel for magnetic field conversion in GRB outflows, whereby the hot, low-sigma jet section thereby produced is the source of the photospheric emission observed in many bursts.

Levinson, Amir [School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel)] [School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel); Begelman, Mitchell C., E-mail: Levinson@wise.tau.ac.il, E-mail: mitch@jila.colorado.edu [JILA, University of Colorado and National Institute of Standards and Technology, 440 UCB, Boulder, CO 80309-0440 (United States)

2013-02-20T23:59:59.000Z

324

asian jet stream: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laboratory Kidston, Joseph 11 Rayleigh Wave-Internal Wave Coupling and Internal Wave Generation Above a Model Jet Stream Mathematics Websites Summary: Rayleigh...

325

Measurement of b-quark Jet Shapes at CDF  

SciTech Connect (OSTI)

The main topic of this thesis is the measurement of b-quark jet shapes at CDF. CDF is an experiment located at Fermilab, in the United States, which studies proton-antiproton collisions at a center of mass energy of 1.96TeV. To reach this energy, the particles are accelerated using the Tevatron accelerator which is currently the highest energy collider in operation. The data used for this analysis were taken between February 2002 and September 2004 and represent an integrated luminosity of about 300 pb{sup -1}. This is the first time that b-quark jet shapes have been measured at hadron colliders. The basis of this measurement lies in the possibility of enhancing the b-quark jet content of jet samples by requiring the jets to be identified as having a displaced vertex inside the jet cone. Such jets are called tagged. This enhances the b-quark jet fraction from about 5% before tagging to 20-40% after tagging, depending on the transverse momentum of the jets. I verified that it is possible to apply this secondary vertex tagging algorithm to different cone jet algorithms (MidPoint and JetClu) and different cone sizes (0.4 and 0.7). I found that the performance of the algorithm does not change significantly, as long as the sub-cone inside which tracks are considered for the tagging is kept at the default value of 0.4. Because the b-quark purity of the jets is still relatively low, it is necessary to extract the shapes of b-quark jets in a statistical manner from the jet shapes both before and after tagging. The other parameters that enter into the unfolding equation used to extract the b-quark jet shapes are the b-jet purities, the biases due to the tagging requirement both for b- and nonbjets and the hadron level corrections. The last of these terms corrects the measured b-jet shapes back to the shapes expected at hadron level which makes comparisons with theoretical models and other experimental results possible. This measurement shows that, despite relatively large systematic uncertainties, the measured b-quark jet shapes are significantly different from those expected from the so-called Pythia Tune A Monte Carlo simulation, the most widely used Leading Order Monte Carlo model at CDF. This difference can be mostly attributed to the fact that the fraction of b-quark jets that originate from flavour creation (where a single b-quark is expected inside the same jet cone) over those that originate from gluon splitting (where two b-quarks are expected to be inside the same jet cone) is slightly different in the Pythia Tune A Monte Carlo predictions than in data. This measurement can help in the tuning of the fraction of gluon splitting to flavour creation b-quark jets in the Monte Carlo simulation. This tuning is particularly important for the extrapolation up to LHC energies where many searches will involve b-quark jets. During the first year of my thesis work, I worked on the implementation of a prototype detector control system for the electromagnetic calorimeter which is being built for the CMS experiment at CERN. The prototype which I implemented was used to monitor and control the high voltage, low voltage, cooling and precision temperature monitoring systems during the summer 2003 test-beam. This was one of the first, almost complete, systems implemented and used by an LHC experiment for test-beam monitoring.

Lister, Alison; /Zurich, ETH

2006-03-01T23:59:59.000Z

326

Generation and Propagation of Inertia Gravity Waves from Vortex Dipoles and Jets Shuguang Wang  

E-Print Network [OSTI]

Generation and Propagation of Inertia Gravity Waves from Vortex Dipoles and Jets Shuguang Wang generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model, moist convection, fronts, upper level jets, geostrophic adjustment and spontaneous generation (Fritts

327

PowerJet Wind Turbine Project  

SciTech Connect (OSTI)

PROJECT OBJECTIVE The PowerJet wind turbine overcomes problems characteristic of the small wind turbines that are on the market today by providing reliable output at a wide range of wind speeds, durability, silent operation at all wind speeds, and bird-safe operation. Prime Energy�s objective for this project was to design and integrate a generator with an electrical controller and mechanical controls to maximize the generation of electricity by its wind turbine. The scope of this project was to design, construct and test a mechanical back plate to control rotational speed in high winds, and an electronic controller to maximize power output and to assist the base plate in controlling rotational speed in high winds. The test model will continue to operate beyond the time frame of the project, with the ultimate goal of manufacturing and marketing the PowerJet worldwide. Increased Understanding of Electronic & Mechanical Controls Integrated With Electricity Generator The PowerJet back plate begins to open as wind speed exceeds 13.5 mps. The pressure inside the turbine and the turbine rotational speed are held constant. Once the back plate has fully opened at approximately 29 mps, the controller begins pulsing back to the generator to limit the rotational speed of the turbine. At a wind speed in excess of 29 mps, the controller shorts the generator and brings the turbine to a complete stop. As the wind speed subsides, the controller releases the turbine and it resumes producing electricity. Data collection and instrumentation problems prevented identification of the exact speeds at which these events occur. However, the turbine, controller and generator survived winds in excess of 36 mps, confirming that the two over-speed controls accomplished their purpose. Technical Effectiveness & Economic Feasibility Maximum Electrical Output The output of electricity is maximized by the integration of an electronic controller and mechanical over-speed controls designed and tested during the course of this project. The output exceeds that of the PowerJet�s 3-bladed counterparts (see Appendix). Durability All components of the PowerJet turbine assembly�including the electronic and mechanical controls designed, manufactured and field tested during the course of this project�proved to be durable through severe weather conditions, with constant operation and no interruption in energy production. Low Cost Materials for the turbine, generator, tower, charge controllers and ancillary parts are available at reasonable prices. Fabrication of these parts is also readily available worldwide. The cost of assembling and installing the turbine is reduced because it has fewer parts and requires less labor to manufacture and assemble, making it competitively priced compared with turbines of similar output manufactured in the U.S. and Europe. The electronic controller is the unique part to be included in the turbine package. The controllers can be manufactured in reasonably-sized production runs to keep the cost below $250 each. The data logger and 24 sensors are for research only and will be unnecessary for the commercial product. Benefit To Public The PowerJet wind-electric system is designed for distributed wind generation in 3 and 4 class winds. This wind turbine meets DOE�s requirements for a quiet, durable, bird-safe turbine that eventually can be deployed as a grid-connected generator in urban and suburban settings. Results As described more fully below and illustrated in the Appendices, the goals and objectives outlined in 2060 SOPO were fully met. Electronic and mechanical controls were successfully designed, manufactured and integrated with the generator. The turbine, tower, controllers and generators operated without incident throughout the test period, surviving severe winter and summer weather conditions such as extreme temperatures, ice and sustained high winds. The electronic controls were contained in weather-proof electrical boxes and the elec

Bartlett, Raymond J

2008-11-30T23:59:59.000Z

328

E-Print Network 3.0 - annular two-phase jet Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and Annular Structures in Geophysical FluidsJets and Annular Structures in Geophysical Fluids Summary: Chapman Conference onChapman Conference on Jets and Annular Structures in...

329

E-Print Network 3.0 - atmospheric-pressure plasma jet Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Databases and Resources 3 Atmospheric Pressure Plasma Jet Treatment of Polyethylene Surfaces for Summary: Atmospheric Pressure Plasma Jet Treatment of Polyethylene...

330

E-Print Network 3.0 - abrasive water jet Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

water jet Search Powered by Explorit Topic List Advanced Search Sample search results for: abrasive water jet Page: << < 1 2 3 4 5 > >> 1 Australasian Fluid Mechanics Conference...

331

Searches in photon and jet states  

SciTech Connect (OSTI)

The authors present recent results from the Collider Detector at Fermilab (CDF) and D0 experiments using data from proton-antiproton collisions with {radical}s = 1.96 TeV at Run II of the Fermilab Tevatron. New physics may appear in events with high transverse momentum objects, including photons and quark or gluon jets. The results described here are of signature-based searches and model-based searches probing supersymmetry, leptoquarks, 4th generation quarks, and large extra dimensions.

Soha, A.; /UC, Davis

2007-06-01T23:59:59.000Z

332

Radiant Energy Power Source for Jet Aircraft  

SciTech Connect (OSTI)

This report beings with a historical overview on the origin and early beginnings of Radiant Energy Power Source for Jet Aircraft. The report reviews the work done in Phase I (Grant DE-FG01-82CE-15144) and then gives a discussion of Phase II (Grant DE-FG01-86CE-15301). Included is a reasonably detailed discussion of photovoltaic cells and the research and development needed in this area. The report closes with a historical perspective and summary related to situations historically encountered on projects of this nature. 15 refs.

Doellner, O.L.

1992-02-01T23:59:59.000Z

333

Do high redshift quasars have powerful jets?  

E-Print Network [OSTI]

for the injection spectrum and surrounding gas profile (set [A] in Mocz et al (2011): the in- jection spectrum is given by a power-law index 2.14 and Lorentz factors ranging between 1 to 106; the surrounding density profile has a powerlaw index of 1.5). We assume... the galaxy hosts of quasars at z > 3 are com- pact (Szomoru et al 2013), and their group and cluster gas have more energy than is explainable by gravitational infall alone (Wu et al 2000; McCarthy et al 2012). Powerful jets are a considerable source of energy...

Fabian, A. C.; Walker, S. A.; Celotti, A.; Ghisellini, G.; Mocz, P.; Blundell, K. M.; McMahon, R. G.

2014-06-04T23:59:59.000Z

334

BioJet Corporation | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: Energy ResourcesJersey:form View source History View NewLtdBioFuelsBioJet

335

Most fish have a forward undulatory swimming mechanism that involves a kinematic propulsive wave travelling down the  

E-Print Network [OSTI]

Most fish have a forward undulatory swimming mechanism that involves a kinematic propulsive wave backwards in a similar way. We compared the kinematics (wave speed, cycle frequency, amplitude, local in the direction opposite to that of swimming. We observe two major kinematic differences. First, the slope of wave

D'Août, Kristiaan

336

VOL. 6, NO. 5, SEPT.-OCT. 1990 J. PROPULSION 621 Stator/Rotor Interaction in a Transonic Turbine  

E-Print Network [OSTI]

on the rotor blade, reflects upstream, and then reflects again off the stator blade Presented as Paper 88 and shows the large unsteadiness in the lift on the rotor blade. Basic NumericalMethod The flowfiVOL. 6, NO. 5, SEPT.-OCT. 1990 J. PROPULSION 621 Stator/Rotor Interaction in a Transonic Turbine

Giles, Mike

337

The influence of solid ankle-foot-orthoses on forward propulsion and dynamic balance in healthy adults during walking  

E-Print Network [OSTI]

The influence of solid ankle-foot-orthoses on forward propulsion and dynamic balance in healthy-stroke hemiparetic subjects, solid polypropylene ankle-foot-orthoses are commonly prescribed to assist in foot clearance during swing while bracing the ankle during stance. Mobility demands, such as changing walking

338

Estimation of Quasi-Stiffness and Propulsive Work of the Human Ankle in the Stance Phase of Walking  

E-Print Network [OSTI]

Estimation of Quasi-Stiffness and Propulsive Work of the Human Ankle in the Stance Phase of Walking of human legs. This work aims to establish statistical models that allow us to predict the ankle quasi-stiffness and net mechanical work for adults walking on level ground. During the stance phase of walking, the ankle

Dollar, Aaron M.

339

Power Balance in a Helicon Plasma Source for Space Propulsion Daniel B. White Jr., Manuel Martinez-Sanchez  

E-Print Network [OSTI]

-Sanchez June 2008 SSL # 9-08 #12;#12;1 Power Balance in a Helicon Plasma Source for Space Propulsion Daniel B. White Jr., Manuel Martinez-Sanchez June 2008 SSL # 9-08 This work is based on the unaltered text

340

Technology Survey and Performance Scaling for the Design of High Power Nuclear Electric Power and Propulsion Systems  

E-Print Network [OSTI]

, use of electric primary propulsion in flight systems has been limited to low-power, solar electric thruster output power are identified. Design evolutions are presented for three thrusters that would1 Technology Survey and Performance Scaling for the Design of High Power Nuclear Electric Power

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Multi-star multi-phase winding for a high power naval propulsion machine with low ripple torques  

E-Print Network [OSTI]

Permanent Magnet (SMPM) Machine designed for naval propulsion is proposed. The design objective of this high if the magnetic couplings between the stars is weak. The 4-star 3-phase winding proposed in this paper is designed star being magnetically shifted by an angle of 15 degrees. This 4-star 3-phase configuration allows

Boyer, Edmond

342

Plasma Jet Driven Magneto-Inertial Fusion (PJMIF)  

E-Print Network [OSTI]

National Security, LLC for NNSA LA-UR-11-07030 #12;Plasma jet experiments can provide cm National Security, LLC for NNSA Imploding plasma liner formed by 30 merging plasma jets with 1.5 MJ, LLC for NNSA MIF ICF Basko et al., Nucl. Fusion, 2000 Magnetic field reduces thermal transport

343

Energy Conservation Constraints on Multiplicity Correlations in QCD Jets  

E-Print Network [OSTI]

We compute analytically the effects of energy conservation on the self-similar structure of parton correlations in QCD jets. The calculations are performed both in the constant and running coupling cases. It is shown that the corrections are phenomenologically sizeable. On a theoretical ground, energy conservation constraints preserve the scaling properties of correlations in QCD jets beyond the leading log approximation.

J. -L. Meunier; R. Peschanski

1996-03-13T23:59:59.000Z

344

Atmospheric Pressure Plasma Jet Treatment of Polyethylene Surfaces for  

E-Print Network [OSTI]

Atmospheric Pressure Plasma Jet Treatment of Polyethylene Surfaces for Adhesion Improvement Uwe studied the activation mechanism of polyethylene (PE) for a pretreatment with a commercial APPJ system jet system from Plasmatreat GmbH (Steinhagen, Germany) was used for the Full Paper Polyethylene (PE

Greifswald, Ernst-Moritz-Arndt-Universität

345

INTERNAL GRAVITY WAVES FROM ATMOSPHERIC JETS AND FRONTS  

E-Print Network [OSTI]

INTERNAL GRAVITY WAVES FROM ATMOSPHERIC JETS AND FRONTS Riwal Plougonven1 and Fuqing Zhang2 consistently highlighted jet exit regions as a favored locus for intense gravity waves, the mechanisms need for improving parameterizations of nonorographic gravity waves in climate models that include

Plougonven, Riwal

346

Acid Placement in Acid Jetting Treatments in Long Horizontal Wells  

E-Print Network [OSTI]

In the Middle East, extended reach horizontal wells (on the order of 25,000 feet of horizontal displacement) are commonly acid stimulated by jetting acid out of drill pipe. The acid is jetted onto the face of the openhole wellbore as the drill pipe...

Sasongko, Hari

2012-07-16T23:59:59.000Z

347

Acid placement and coverage in the acid jetting process  

E-Print Network [OSTI]

Many open-hole acid treatments are being conducted by pumping acid through jetting ports placed at the end of coiled tubing or drill pipe. The filter-cake on the bore-hole is broken by the jet; the acid-soluble material is dissolved, creating...

Mikhailov, Miroslav I.

2009-05-15T23:59:59.000Z

348

Behavior of shale oil jet fuels at variable severities  

SciTech Connect (OSTI)

Catalytic hydroprocessed shale oil jet fuels in the USA were characterized and compared with petroleum jet fuel to demonstrate their possibility as a conventional jet fuel substitute. The shale oils (Geokinetics, Occidental, Paraho and Tosco II) were hydrotreated in a 0.058m ID by 1.52m long reactor containing Ni/MO/Al/sub 2/O/sub 3/ catalyst. The fractionated hydrogenated shale oils at jet fuel ranges (120-300/sup 0/C) were analyzed for composition and physical properties. The increasing hydroprocessing severity proportionally decreased nitrogen, sulfur, olefins, and aromatics, and increased hydrogen content. The nitrogen content even at high severity conditions was considerably higher than that of conventional jet fuel. Sulfur and olefin contents were lower at all severities. The heat of combustion and the physical properties, except the freezing point, were comparable to petroleum jet fuels. The yields of jet fuels increased proportionally to increased severity. The study showed that high severity hydroprocessing gave better performance in processing shale oils to jet fuels.

Mukherjee, N.L.

1988-01-01T23:59:59.000Z

349

Modeling of NOx formation in circular laminar jet flames  

E-Print Network [OSTI]

-premixed isolated circular laminar jet flame. The jet consists of the fuel rich inner region and the O2 rich outer region. The model estimates both thermal NOx and prompt NOx assuming single step kinetics for NOx formation and a thin flame model. Further the amount...

Siwatch, Vivek

2007-04-25T23:59:59.000Z

350

Measurements of Vector Bosons Produced in Association with Jets  

E-Print Network [OSTI]

The latest D0 and CDF measurements of the important $W+{\\rm jets}$ and $Z/\\gamma^{*}+{\\rm jets}$ processes are described, along with a discussion of the comparisons that have been made to LO and NLO perturbative QCD predictions.

Cooper, Ben

2008-01-01T23:59:59.000Z

351

Characterization of turbulent jet mixing in cylindrical tanks  

E-Print Network [OSTI]

, for the most part, confirms many of the findings of previous studies of jet mixing. First, mixing time in jet-mixed systems depends primarily upon the mass of the fluid in a tank and the amount of addition, to maximize the efficient transfer of momentum...

Schulte, Casey M

1998-01-01T23:59:59.000Z

352

Modified Black Hole with Polar Jet and Vortex  

E-Print Network [OSTI]

There are many models relating an accretion disk of Black Hole to jet outflow. The herein heuristic model describes the continuation of an external accretion disk to an internal accretion disk for less than Black Hole horizon, and subsequent polar jet outflow along polar axis out of polar vortex wherein the event horizon is no longer descriptive.

T. Tmmalm

2001-12-06T23:59:59.000Z

353

Search for New Physics in the Jets + Missing ET topology  

SciTech Connect (OSTI)

Although the standard model of particle physics agrees perfectly with experimental data, it is unlikely the final theory describing particles and their interactions. New phenomena has been searched in the jets and missing transverse energy topology. Such phenomena may be due to the pair production of leptoquarks decaying into a quark and a neutrino or the pair production of stops decaying into a charm and a neutralino which is assumed to be the lightest supersymmetric particle. These searches have been performed with the D0 detector at hadronic collider TeVatron with a center of mass energy of 1.96 TeV. This kind of search needs a good understanding of the jet energy calibration. The determination of the relative jet energy scale has allowed them to reduce the systematic uncertainties on the jet energy measurement when comparing the data and the simulation. Moreover a new method has been developed in order to correct simulated jets for the differences observed in the jet energy scale, the jet energy resolution and the jet reconstruction efficiency between the data and the simulation. The data analysis, performed with an integrated luminosity of 310 pb{sup -1}, has not observed any excess. This result is interpreted in terms of limit on the mass of the particles: leptoquarks with a mass smaller than 136 GeV and stops with a mass smaller than 131 GeV, for a neutralino mass equal to 46 GeV, are excluded with 95% confidence level.

Makovec, Nikola Michel; /Orsay

2006-05-01T23:59:59.000Z

354

Direct Numerical Simulation of Autoignition in a Jet in a Cross...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

turbines provide excellent opportunities for environmentally friendly propulsion and electricity generation, but are severely limited by the danger of autoignition of the...

355

Di-jet asymmetric momentum transported by QGP fluid  

E-Print Network [OSTI]

We study the collective flow of the {QGP}-fluid which transports the energy and momentum deposited from jets. Simulations of the propagation of jets together with expansion of the {QGP}-fluid are performed by solving relativistic hydrodynamic equations numerically in the fully (3+1)-dimensional space. Mach cones are induced by the energy-momentum deposition from jets and extended by the expansion of the {QGP}. As a result, a large fraction of the transverse momentum deposited from jets is compensated by low-$p_{T}$ particles at large angles from the jet axis. This result is consistent with the data from the {CMS} Collaboration and gives a novel interpretation of them.

Yasuki Tachibana; Tetsufumi Hirano

2014-10-15T23:59:59.000Z

356

Spin analyzing power for polarized top decays with jets  

E-Print Network [OSTI]

We perform perturbative QCD factorization of infrared radiations associated with an energetic $b$ quark from a polarized top quark decay, taking the semi-leptonic channel as an example. The resultant formula is expressed as a convolution of an infrared-finite heavy-quark kernel with a $b$-quark jet function. Evaluating the heavy-quark kernel up to leading order in the coupling constant and adopting the jet function from QCD resummation, we predict the dependence of the spin analyzing power for a polarized top quark on the invariant mass of the $b$-quark jet. It is observed that the spin analyzing power could be enhanced by a factor 2 compared to the inclusive case with the jet mass being integrated over. It is worthwhile to test experimentally the enhancement of the spin analyzing power due to the inclusion of jet dynamics.

Yoshio Kitadono; Hsiang-nan Li

2014-04-10T23:59:59.000Z

357

Propulsion system for a motor vehicle using a bidirectional energy converter  

DOE Patents [OSTI]

A motor vehicle propulsion system includes an electrical energy source and a traction motor coupled to receive electrical energy from the electrical energy source. The system also has a first bus provided electrical energy by the electrical energy source and a second bus of relatively lower voltage than the first bus. In addition, the system includes an electrically-driven source of reaction gas for the electrical energy source, the source of reaction gas coupled to receive electrical energy from the first bus. Also, the system has an electrical storage device coupled to the second bus for storing electrical energy at the lower voltage. The system also includes a bidirectional energy converter coupled to convert electrical energy from the first bus to the second bus and from the second bus to the first bus.

Tamor, Michael Alan (Toledo, OH); Gale, Allan Roy (Livonia, MI)

1999-01-01T23:59:59.000Z

358

Absence of jamming in ant trails: Feedback control of self propulsion and noise  

E-Print Network [OSTI]

We present a model of ant traffic considering individual ants as self-propelled particles undergoing single file motion on a one-dimensional trail. Recent experiments on unidirectional ant traffic in well-formed natural trails showed that the collective velocity of ants remains approximately unchanged, leading to absence of jamming even at very high densities [ John et. al., Phys. Rev. Lett. 102, 108001 (2009) ]. Assuming a feedback control mechanism of self-propulsion force generated by each ant using information about the distance from the ant in front, our model captures all the main features observed in the experiment. The distance headway distribution shows a maximum corresponding to separations within clusters. The position of this maximum remains independent of average number density. We find a non-equilibrium first order transition, with the formation of an infinite cluster at a threshold density where all the ants in the system suddenly become part of a single cluster.

Chaudhuri, Debasish

2014-01-01T23:59:59.000Z

359

Preliminary Design of a Manned Nuclear Electric Propulsion Vehicle Using Genetic Algorithms  

SciTech Connect (OSTI)

Nuclear electric propulsion (NEP) vehicles will be needed for future manned missions to Mars and beyond. Candidate designs must be identified for further detailed design from a large array of possibilities. Genetic algorithms have proven their utility in conceptual design studies by effectively searching a large design space to pinpoint unique optimal designs. This research combined analysis codes for NEP subsystems with a genetic algorithm. The use of penalty functions with scaling ratios was investigated to increase computational efficiency. Also, the selection of design variables for optimization was considered to reduce computation time without losing beneficial design search space. Finally, trend analysis of a reference mission to the asteroids yielded a group of candidate designs for further analysis.

Irwin, Ryan W. [School of Aeronautics and Astronautics, Purdue University, West Lafayette, IN 47907 (United States); Tinker, Michael L. [Spacecraft and Vehicle Systems Department, NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States)

2005-02-06T23:59:59.000Z

360

Phase Space and Jet Definitions in SCET  

E-Print Network [OSTI]

We discuss consistent power counting for integrating soft and collinear degrees of freedom over arbitrary regions of phase space in the soft-collinear effective theory (SCET), and illustrate our results at one loop with several jet algorithms: JADE, Sterman-Weinberg and k_T. Consistently applying SCET power-counting in phase space, along with non-trivial zero-bin subtractions, prevents double-counting of final states. The resulting phase-space integrals over soft and collinear regions are individually ultraviolet divergent, but the phase-space ultraviolet divergences cancel in the sum. Whether the soft and collinear contributions are individually infrared safe depends on the jet definition. We show that while this is true at one loop for JADE and Sterman-Weinberg, the k_T algorithm does not factorize into individually infrared safe soft and collinear pieces in dimensional regularization. We point out that this statement depends on the ultraviolet regulator, and that in a cutoff scheme the soft functions are infrared safe.

William Man-Yin Cheung; Michael Luke; Saba Zuberi

2009-10-13T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Large area atmospheric-pressure plasma jet  

DOE Patents [OSTI]

Large area atmospheric-pressure plasma jet. A plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two planar, parallel electrodes are employed to generate a plasma in the volume therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly spacing the rf-powered electrode. Because of the atmospheric pressure operation, there is a negligible density of ions surviving for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike the situation for low-pressure plasma sources and conventional plasma processing methods.

Selwyn, Gary S. (Los Alamos, NM); Henins, Ivars (Los Alamos, NM); Babayan, Steve E. (Huntington Beach, CA); Hicks, Robert F. (Los Angeles, CA)

2001-01-01T23:59:59.000Z

362

Heavy vehicle propulsion system materials program: Semiannual progress report, April 1996--September 1996  

SciTech Connect (OSTI)

The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks. The Office of Transportation Technologies, Office of Heavy Vehicle Technologies (OTT OHVT) has an active program to develop the technology for advanced LE-55 diesel engines with 55% efficiency and low emissions levels of 2.0 g/bhp-h NO{sub x} and 0.05 g/bhp-h particulates. The goal is also for the LE-55 engine to run on natural gas with efficiency approaching that of diesel fuel. The LE-55 program is being completed in FY 1997 and, after approximately 10 years of effort, has largely met the program goals of 55% efficiency and low emissions. However, the commercialization of the LE-55 technology requires more durable materials than those that have been used to demonstrate the goals. Heavy Vehicle Propulsion System Materials will, in concert with the heavy duty diesel engine companies, develop the durable materials required to commercialize the LE-55 technologies. OTT OHVT also recognizes a significant opportunity for reduction in petroleum consumption by dieselization of pickup trucks, vans, and sport utility vehicles. Application of the diesel engine to class 1, 2, and 3 trucks is expected to yield a 35% increase in fuel economy per vehicle. The foremost barrier to diesel use in this market is emission control. Once an engine is made certifiable, subsequent challenges will be in cost; noise, vibration, and harshness (NVH); and performance. Separate abstracts have been submitted to the database for contributions to this report.

Johnson, D.R.

1997-04-01T23:59:59.000Z

363

Propulsion System Materials Program semiannual progress report for April 1995 through September 1995  

SciTech Connect (OSTI)

Significant accomplishments in fabricating ceramic components for the DOE, NASA, and DOD advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. These programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and data base and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. An assessment of needs was completed, and a 5-year program plan was developed with extensive input from private industry. During the course of the Propulsion System Materials Program, remarkable progress has been made in the development of reliable structural ceramics. However, further work is needed to reduce the cost of ceramics to facilitate their commercial introduction, especially in the highly cost-sensitive automotive market. To this end, the direction of the Propulsion System Materials Program is now shifting toward reducing the cost of ceramics to facilitate commercial introduction of ceramic components for near-term engine applications. In response to extensive input from industry, the plan is to extend the engine types which were previously supported to include near-term (5--10 years) applications in conventional automobile and diesel truck engines. To facilitate the rapid transfer of this technology to US industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities. A systematic approach to reducing the cost of components is envisioned. The work elements are as follows: economic cost modeling, ceramic machining, powder synthesis, alternative forming and densification processes, yield improvement, system design studies, standards development, low-expansion ceramics, and testing and data base development.

NONE

1996-04-01T23:59:59.000Z

364

I N T R O D U C T I O N Biomimetics and Marine Technology  

E-Print Network [OSTI]

, jet propulsion), stealth (e.g., camouflage, low acoustic signature), and use of compliant materials (e

Fish, Frank

365

Lessons from System Development  

E-Print Network [OSTI]

sci- entists and engineers conducts ground operations. Most of these people are at the Jet Propulsion

Filman, Robert E.

366

International Journal of Applied Earth Observation and Geoinformation 20 (2013) 419 Contents lists available at SciVerse ScienceDirect  

E-Print Network [OSTI]

Estudios Avanzados en Zonas Aridas (CEAZA), Universidad de la Serena, La Serena, Chile d Jet Propulsion

Haak, Hein

367

Drying: a comparison of radial jet reattachment and standard in-line jets  

E-Print Network [OSTI]

line of the nozzle but is shown in two dimensions as seen in the flow visualization. The flow rate of water corresponds to an exit velocity in air of approximately 75 meters per second, using Reynolds number similarity. The reattachment ring.... In this research endeavor, RJR nozzles have been compared to the drying industry's common method of air impingement drying, namely, standard In-Line Jets (ILJ), for several different combinations of flow and geometrical parameters. This gives evidence...

Habetz, Darren Keith

2012-06-07T23:59:59.000Z

368

X-ray Emission Processes in Radio Jets  

E-Print Network [OSTI]

The emission processes responsible for the observed X-rays from radio jets are commonly believed to be non-thermal, but in any particular case, it is unclear if synchrotron emission or one or more varieties of inverse Compton emission predominates. We present a formulation of inverse Compton emission from a relativistically moving jet (``IC/beaming'') which relies on radio emitting synchrotron sources for which the energy densities in particles and fields are comparable. We include the non-isotropic nature of inverse Compton scattering of the relativistic electrons on photons of the cosmic microwave background (CMB) and provide beaming parameters for a number of jets. A list of X-ray emitting jets is given and the jets are classified on the basis of their morphology and spectral energy distribution to determine their likely emission process. We conclude that these jets have significant bulk relativistic velocities on kpc scales; that higher redshift sources require less beaming because the energy density of the CMB is significantly greater than locally; and that for some nearby sources, synchrotron X-ray emission predominates because the jet makes a large angle to the line of sight.

D. E. Harris; H. Krawczynski

2001-09-27T23:59:59.000Z

369

Effect of severity on catalytic hydroprocessed shale oil jet fuels  

SciTech Connect (OSTI)

Catalytic hydroprocessed shale oil jet fuels in the USA were characterized and compared with petroleum jet fuel to demonstrate their possibility as a conventional jet fuel substitute. The shale oils (Geokinetics, Occidental, Paraho and Tosco II) were hydrotreated in a 0.0508m ID by K1.524m long reactor containing Ni/Mo/Al/sub 2/O/sub 3/ catalyst. The fractionated hydrogenated shale oils at jet fuel ranges (120-300/degree/C) were analyzed for composition and physical properties. The increasing hydroprocessing severity proportionally decreased nitrogen, sulfur, olefins, aromatics and increased hydrogen content. The nitrogen content was considerable higher even at high severity conditions. Sulfur and olefin contents were lower at all severities. The heat of combustion and the physical properties, except the freezing point, were comparable to petroleum jet fuels. The yields of jet fuels increased proportionally to increased severity. The study showed that high severity hydroprocessing gave better performance in processing shale oils to jet fuels.

Mukherjee, N.L.

1987-01-01T23:59:59.000Z

370

Gamma-ray burst jets: uniform or structured?  

E-Print Network [OSTI]

The structure of Gamma-Ray Burst (GRB) jets impacts on their prompt and afterglow emission properties. Insights into the still unknown structure of GRBs can be achieved by studying how different structures impact on the luminosity function (LF): i) we show that low ($10^{46} 10^{50}$ erg/s) luminosity GRBs can be described by a unique LF; ii) we find that a uniform jet (seen on- and off-axis) as well as a very steep structured jet (i.e. $\\epsilon(\\theta) \\propto \\theta^{-s}$ with $s > 4$) can reproduce the current LF data; iii) taking into account the emission from the whole jet (i.e. including contributions from mildly relativistic, off-axis jet elements) we find that $E_{\\rm iso}(\\theta_{\\rm v})$ (we dub this quantity "apparent structure") can be very different from the intrinsic structure $\\epsilon(\\theta)$: in particular, a jet with a Gaussian intrinsic structure has an apparent structure which is more similar to a power law. This opens a new viewpoint on the quasi-universal structured jet hypothesis.

Salafia, O S; Nappo, F; Ghisellini, G; Ghirlanda, G; Salvaterra, R; Tagliaferri, G

2015-01-01T23:59:59.000Z

371

The JET Hydrogen-Oxygen Recombination Sensor – A Safety Device for Hydrogen Isotope Processing Systems  

E-Print Network [OSTI]

The JET Hydrogen-Oxygen Recombination Sensor – A Safety Device for Hydrogen Isotope Processing Systems

372

Tungsten Transport in JET H-mode Plasmas in Hybrid Scenario, Experimental Observations and Modelling  

E-Print Network [OSTI]

Tungsten Transport in JET H-mode Plasmas in Hybrid Scenario, Experimental Observations and Modelling

373

Bouncing jet: A Newtonian liquid rebounding off a free surface Matthew Thrasher,* Sunghwan Jung,  

E-Print Network [OSTI]

horizontally with respect to the jet. Previous observations of jets rebounding off a bath e.g., the Kaye effect of Newtonian fluids, including mineral oil poured by hand. A thin layer of air separates the bouncing jet from in studying the bouncing jet e.g., noncoalescence, lubrication, and entrainment are ubiq- uitous in fluid

Weeks, Eric R.

374

Overview of Transport, Fast Particle and Heating and Current Drive Physics using Tritium in JET plasmas  

E-Print Network [OSTI]

Overview of Transport, Fast Particle and Heating and Current Drive Physics using Tritium in JET plasmas

375

Effect of Sawtooth Activity on Tritium and Beam Deuterium Evolution in Trace Tritium Experiments on JET  

E-Print Network [OSTI]

Effect of Sawtooth Activity on Tritium and Beam Deuterium Evolution in Trace Tritium Experiments on JET

376

New Safety and Technical Challenges and Operational Experience on the JET First Trace Tritium Experiment  

E-Print Network [OSTI]

New Safety and Technical Challenges and Operational Experience on the JET First Trace Tritium Experiment

377

Overview of Transport, Fast Particle and Heating and Current Drive Physics using Tritium in JET Plasmas  

E-Print Network [OSTI]

Overview of Transport, Fast Particle and Heating and Current Drive Physics using Tritium in JET Plasmas

378

Recent Steps Towards a Controlled Thermonuclear Fusion Reactor with Results from the JET Tokamak Device  

E-Print Network [OSTI]

Recent Steps Towards a Controlled Thermonuclear Fusion Reactor with Results from the JET Tokamak Device

379

Algorithms for the Automatic Identification of MARFEs and UFOs in JET Database of Visible Camera Videos  

E-Print Network [OSTI]

Algorithms for the Automatic Identification of MARFEs and UFOs in JET Database of Visible Camera Videos

380

Turbulent round jet under gravity waves  

E-Print Network [OSTI]

) Turbulent shear stress &u'w'&/&u, & versus z/x. . . 26 3-5 Overlapped mean axial velocity &u&/&u, & versus zJx of the case of A = 0. 5 cm at six locations corresponding to figure 3-4(a) . . 28 3-6 Horizontal turbulent velocity &u' &' /&u, & versus zJx... of the case of A = 0. 5 cm with z, = 0 at. the moving jet centerline in the range of (a) x/D = 40 - 95, (b) x/D = 40 ? 57, and (c) x/D = 64 - 95 . . 30 3-7 Vertical turbulent velocity &w' & /&u, & versus z Jx of the case of A = 0. 5 cm FIGURE Page with z...

Ryu, Yong Uk

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Higher-Order Corrections to Timelike Jets  

SciTech Connect (OSTI)

We present a simple formalism for the evolution of timelike jets in which tree-level matrix element corrections can be systematically incorporated, up to arbitrary parton multiplicities and over all of phase space, in a way that exponentiates the matching corrections. The scheme is cast as a shower Markov chain which generates one single unweighted event sample, that can be passed to standard hadronization models. Remaining perturbative uncertainties are estimated by providing several alternative weight sets for the same events, at a relatively modest additional overhead. As an explicit example, we consider Z {yields} q{bar q} evolution with unpolarized, massless quarks and include several formally subleading improvements as well as matching to tree-level matrix elements through {alpha}{sub s}{sup 4}. The resulting algorithm is implemented in the publicly available VINCIA plugin to the PYTHIA8 event generator.

Giele, W.T.; /Fermilab; Kosower, D.A.; /Saclay, SPhT; Skands, P.Z.; /CERN

2011-02-01T23:59:59.000Z

382

A FLUX ROPE ERUPTION TRIGGERED BY JETS  

SciTech Connect (OSTI)

We present an observation of a filament eruption caused by recurrent chromospheric plasma injections (surges/jets) on 2006 July 6. The filament eruption was associated with an M2.5 two-ribbon flare and a coronal mass ejection (CME). There was a light bridge in the umbra of the main sunspot of NOAA 10898; one end of the filament was terminated at the region close to the light bridge, and recurrent surges were observed to be ejected from the light bridge. The surges occurred intermittently for about 8 hr before the filament eruption, and finally a clear jet was found at the light bridge to trigger the filament eruption. We analyzed the evolutions of the relative darkness of the filament and the loaded mass by the continuous surges quantitatively. It was found that as the occurrence of the surges, the relative darkness of the filament body continued growing for about 3-4 hr, reached its maximum, and kept stable for more than 2 hr until it erupted. If suppose 50% of the ejected mass by the surges could be trapped by the filament channel, then the total loaded mass into the filament channelwill be about 0.57x10{sup 16} g with a momentum of 0.57x10{sup 22} g cm s{sup -1} by 08:08 UT, which is a non-negligible effect on the stability of the filament. Based on the observations, we present a model showing the important role that recurrent chromospheric mass injection play in the evolution and eruption of a flux rope. Our study confirms that the surge activities can efficiently supply the necessary material for some filament formation. Furthermore, our study indicates that the continuous mass with momentum loaded by the surge activities to the filament channel could make the filament unstable and cause it to erupt.

Guo Juan; Zhang Hongqi; Deng Yuanyong; Lin Jiaben; Su Jiangtao [Key Laboratory of Solar Activity, National Astronomical Observatories, Beijing 100012 (China); Liu Yu, E-mail: guojuan@bao.ac.c [Yunnan Astronomical Observatory, National Astronomical Observatories, Kunming 650011 (China)

2010-03-10T23:59:59.000Z

383

AEA Fluidic Pulse Jet Mixer. Innovative Technology Summary Report  

SciTech Connect (OSTI)

AEA's Fluidic Pulse Jet Mixer was developed to mix and maintain the suspension of solids and to blend process liquids. The mixer can be used to combine a tank's available supernate with the sludge into a slurry that is suitable for pumping. The system uses jet nozzles in the tank coupled to a charge vessel. Then, a jet pump creates a partial vacuum in the charge vessel allowing it to be filled with waste. Next, air pressure is applied to the charge vessel, forcing sludge back into the tank and mixing it with the liquid waste. When the liquid waste contains 10% solids, a batch is pumped out of the tank.

None

1999-08-01T23:59:59.000Z

384

High order harmonic generation in dual gas multi-jets  

SciTech Connect (OSTI)

High order harmonic generation (HHG) in gas media suffers from a low conversion efficiency that has its origins in the interaction of the atom/molecule with the laser field. Phase matching is the main way to enhance the harmonic flux and several solutions have been designed to achieve it. Here we present numerical results modeling HHG in a system of multi-jets in which two gases alternate: the first gas jet (for example Ne) generates harmonics and the second one which ionizes easier, recover the phase matching condition. We obtain configurations which are experimentally feasible with respect to pressures and dimensions of the jets.

Tosa, Valer, E-mail: valer.tosa@itim-cj.ro, E-mail: calin.hojbota@itim-cj.ro; Hojbota, Calin, E-mail: valer.tosa@itim-cj.ro, E-mail: calin.hojbota@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, Donath 65-103, 400293 Cluj-Napoca (Romania)] [National Institute for Research and Development of Isotopic and Molecular Technologies, Donath 65-103, 400293 Cluj-Napoca (Romania)

2013-11-13T23:59:59.000Z

385

Panchromatic Views of Large-Scale Extragalactic Jets  

SciTech Connect (OSTI)

Highlights of recent observations of extended jets in AGN are presented. Specifically, we discuss new spectral constraints enabled by Spitzer, studies of the highest-redshift (z{approx}4) radio/X-ray quasar jets, and a new VLBA detection of superluminal motion in the M87 jet associated with a recent dramatic X-ray outburst. Expanding on the title, inverse Compton emission from extended radio lobes is considered and a testable prediction for the gamma-ray emission in one exemplary example is presented. Prospects for future studies with ALMA and low-frequency radio interferometers are briefly described.

Cheung, C.C.; /KIPAC, Menlo Park

2007-06-01T23:59:59.000Z

386

Heavy Vehicle Propulsion System Materials Program Semiannual Progress Report for October 1998 Through March 1999  

SciTech Connect (OSTI)

The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks. The Office of Transportation Technologies, Office of Heavy Vehicle Technologies (OIT OHVT) has an active program to develop the technology for advanced LE-55 diesel engines with 55% efficiency and low emissions levels of 2.0 g/bhp-h NOX and 0.05 g/bhp-h particulate. The goal is also for the LE-55 engine to run on natural gas with efficiency approaching that of diesel fuel. The LE-55 program is being completed in FY 1997 and, after approximately 10 years of effort, has largely met the program goals of 55% efficiency and low emissions. However, the commercialization of the LE-55 technology requires more durable materials than those that have been used to demonstrate the goals. Heavy Vehicle Propulsion System Materials will, in concert with the heavy duty diesel engine companies, develop the durable materials required to commercialize the LE-55 technologies. OIT OHVT also recognizes a significant opportunity for reduction in petroleum consumption by dieselization of pickup trucks, vans, and sport utility vehicles. Application of the diesel engine to class 1,2, and 3 trucks is expected to yield a 35% increase in fuel economy per vehicle. The foremost barrier to diesel use in this market is emission control. Once an engine is made certifiable, subsequent challenges will be in cost; noise, vibration, and harshness (NVH); and performance. The design of advanced components for high-efficiency diesel engines has, in some cases, pushed the performance envelope for materials of construction past the point of reliable operation. Higher mechanical and tribological stresses and higher temperatures of advanced designs limit the engine designer; advanced materials allow the design of components that may operate reliably at higher stresses and temperatures, thus enabling more efficient engine designs. Advanced materials also offer the opportunity to improve the emissions, NVH, and performance of diesel engines for pickup trucks, vans, and sport utility vehicles. The principal areas of research are: (1) Cost Effective High Performance Materials and Processing; (2) Advanced Manufacturing Technology; (3)Testing and Characterization; and (4) Materials and Testing Standards.

Johnson, R.D.

1999-06-01T23:59:59.000Z

387

Double row loop-coil configuration for high-speed electrodynamic maglev suspension, guidance, propulsion and guideway directional switching  

DOE Patents [OSTI]

A stabilization and propulsion system are disclosed comprising a series of loop-coils arranged in parallel rows wherein two rows combine to form one of two magnetic rails. Levitation and lateral stability are provided when the induced field in the magnetic rails interacts with the superconducting magnets mounted on the magnetic levitation vehicle. The loop-coils forming the magnetic rails have specified dimensions and a specified number of turns and by constructing differently these specifications, for one rail with respect to the other, the angle of tilt of the vehicle can be controlled during directional switching. Propulsion is provided by the interaction of a traveling magnetic wave associated with the coils forming the rails and the superconducting magnets on the vehicle. 12 figs.

He, J.; Rote, D.M.

1996-05-21T23:59:59.000Z

388

High density cluster jet target for storage ring experiments  

E-Print Network [OSTI]

The design and performance of a newly developed cluster jet target installation for hadron physics experiments are presented which, for the first time, is able to generate a hydrogen cluster jet beam with a target thickness of above $10^{15}\\,\\mathrm{atoms/cm}^2$ at a distance of two metres behind the cluster jet nozzle. The properties of the cluster beam and of individual clusters themselves are studied at this installation. Special emphasis is placed on measurements of the target beam density as a function of the relevant parameters as well as on the cluster beam profiles. By means of a time-of-flight setup, measurements of the velocity of single clusters and velocity distributions were possible. The complete installation, which meets the requirements of future internal fixed target experiments at storage rings, and the results of the systematic studies on hydrogen cluster jets are presented and discussed.

Alexander Täschner; Esperanza Köhler; Hans-Werner Ortjohann; Alfons Khoukaz

2011-11-02T23:59:59.000Z

389

Probabilistic picture of in-medium jet evolution  

E-Print Network [OSTI]

We briefly discuss the recently developed probabilistic picture for in-medium jet evolution that is driven by independent multiple scatterings and branchings. These are controlled by the jet quenching parameter $\\hat q$. In this framework, large radiative corrections to $p_\\perp$-broadening of partons in the jet, enhanced by a double logarithm (DL) of the medium size $L$, are recovered. We argue that these non-local corrections are universal and can be reabsorbed in a renormalization of the jet quenching parameter without spoiling the probabilistic picture. As a consequence, we find that for large media, the mean radiative energy loss result scales as $L^{2+\\gamma}$, where the anomalous dimension $\\gamma=2\\sqrt{\\alpha_sN_c/\\pi}$.

Yacine Mehtar-Tani

2014-04-29T23:59:59.000Z

390

Cellular membrane collapse by atmospheric-pressure plasma jet  

SciTech Connect (OSTI)

Cellular membrane dysfunction caused by air plasma in cancer cells has been studied to exploit atmospheric-pressure plasma jets for cancer therapy. Here, we report that plasma jet treatment of cervical cancer HeLa cells increased electrical conductivity across the cellular lipid membrane and caused simultaneous lipid oxidation and cellular membrane collapse. We made this finding by employing a self-manufactured microelectrode chip. Furthermore, increased roughness of the cellular lipid membrane and sequential collapse of the membrane were observed by atomic force microscopy following plasma jet treatment. These results suggest that the cellular membrane catastrophe occurs via coincident altered electrical conductivity, lipid oxidation, and membrane roughening caused by an atmospheric-pressure plasma jet, possibly resulting in cellular vulnerability to reactive species generated from the plasma as well as cytotoxicity to cancer cells.

Kim, Kangil; Sik Yang, Sang, E-mail: jsjlee@ajou.ac.kr, E-mail: ssyang@ajou.ac.kr [Department of Electrical and Computer Engineering, Ajou University, Suwon 443-749 (Korea, Republic of); Jun Ahn, Hak; Lee, Jong-Soo, E-mail: jsjlee@ajou.ac.kr, E-mail: ssyang@ajou.ac.kr [Department of Biological Sciences, Ajou University, Suwon 443-749 (Korea, Republic of)] [Department of Biological Sciences, Ajou University, Suwon 443-749 (Korea, Republic of); Lee, Jae-Hyeok; Kim, Jae-Ho [Department of Molecular Science and Technology, Ajou University, Suwon 443-749 (Korea, Republic of)] [Department of Molecular Science and Technology, Ajou University, Suwon 443-749 (Korea, Republic of)

2014-01-06T23:59:59.000Z

391

Hydrodynamics of Hypersonic Jets: Experiments and Numerical Simulations  

E-Print Network [OSTI]

Stars form in regions of the galaxy that are denser and cooler than the mean interstellar medium. These regions are called Giant Molecular Clouds. At the beginning of their life, up to $10^5-10^6$ years, stars accrete matter from their rich surrounding environment and are origin of a peculiar phenomenon that is the jet emission. Jets from Young Stellar Objects (YSOs) are intensively studied by the astrophysical community by observations at different wavelengths, analytical and numerical modeling and laboratory experiments. Indications about the jet propagation and its resulting morphologies are here obtained by means of a combined study of hypersonic jets carried out both in the laboratory and by numerical simulations.

Belan, Marco; Tordella, Daniela; Massaglia, Silvano; Ferrari, Attilio; Mignone, Andrea; Bodenschatz, Eberhard

2011-01-01T23:59:59.000Z

392

The hydraulic bump: The surface signature of a plunging jet  

E-Print Network [OSTI]

When a falling jet of fluid strikes a horizontal fluid layer, a hydraulic jump arises downstream of the point of impact, provided a critical flow rate is exceeded. We here examine a phenomenon that arises below this jump ...

Labousse, M.

393

De-commoditizing the commercial jet engine business  

E-Print Network [OSTI]

This thesis project is a comprehensive application of the Delta Model at a major jet engine manufacturer. It will assess and contrast customer segmentation and customer value proposition via primary research. It will also ...

Soucy, Arthur L

2007-01-01T23:59:59.000Z

394

Experimental High Velocity Acid Jetting in Limestone Carbonates  

E-Print Network [OSTI]

Acid jetting is a well stimulation technique that is used in carbonate reservoirs. It typically involves injecting acid down hole at high flow rates through small orifices which cause high velocities of acid to strike the borehole wall...

Holland, Christopher

2014-04-30T23:59:59.000Z

395

SS433: on the uniqueness of cool relativistic jets  

E-Print Network [OSTI]

The relativistic jets of SS433 are outstanding for their optical thermal radiation.The radiation is produced by small clouds ($10^8$ cm) whose lifetime is about $10^3$ times larger than the gas-dynamical crushing time. We show that the clouds reside in thermal and dynamical balance as long as they collisionally interact with the wind of the supercritical accretion disk. The interaction is caused by the precessional movement of the jets and takes place only in the sweep-out zone. Beyond the sweep-out zone the interaction ceases and optical jets just terminate. The cloud magnetic field amplified in course of movement through a medium could play a role in containing a cloud. Thus, the clue to the uniqueness of the optical jets of SS433 is thought to be their precessional movement, which provides an opportunity for collisional interaction of the clouds with the wind.

A. A. Panferov

1999-05-13T23:59:59.000Z

396

Microjet based noise control of supersonic jets on carrier decks  

E-Print Network [OSTI]

The effectiveness of ground plane water microjet control on the noise generated by a supersonic, ideally expanded, Mach 1.5, impinging jet was determined. Using a converging-diverging nozzle with a design Mach number of ...

Ragaller, Paul Aaron

2014-01-01T23:59:59.000Z

397

The reduction of supersonic jet noise using pulsed microjet injection  

E-Print Network [OSTI]

This thesis is concerned with the active control of supersonic jet noise using pulsed microjet injection at the nozzle exit. Experimental investigations were carried out using this control method on an ideally expanded ...

Ragaller, Paul Aaron

2007-01-01T23:59:59.000Z

398

Eddy-mean flow interactions in western boundary current jets  

E-Print Network [OSTI]

This thesis examines the nature of eddy-mean flow interactions in western boundary current jets and recirculation gyre dynamics from both theoretical and observational perspectives. It includes theoretical studies of ...

Waterman, Stephanie N

2009-01-01T23:59:59.000Z

399

A critical review of world jet transport safety  

E-Print Network [OSTI]

This thesis is intended to serve as a comprehensive introduction to world jet transport safety and aviation fire safety. Divided into six sections, this thesis contains: 1) a statistical review of overall levels of safety ...

Achtmann, Eric D.

1995-01-01T23:59:59.000Z

400

Exploration of Plasma Jets Approach to High Energy Density Physics  

SciTech Connect (OSTI)

High-energy-density laboratory plasma (HEDLP) physics is an emerging, important area of research in plasma physics, nuclear physics, astrophysics, and particle acceleration. While the HEDLP regime occurs at extreme conditions which are often found naturally in space but not on the earth, it may be accessible by colliding high intensity plasmas such as high-energy-density plasma jets, plasmoids or compact toroids from plasma guns. The physics of plasma jets is investigated in the context of high energy density laboratory plasma research. This report summarizes results of theoretical and computational investigation of a plasma jet undergoing adiabatic compression and adiabatic expansion. A root-mean-squared (rms) envelope theory of plasma jets is developed. Comparison between theory and experiment is made. Good agreement between theory and experiment is found.

Chen, Chiping [Massachusetts Institute of Technology

2013-08-26T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

GRAVITATIONAL WAVES OF JET PRECESSION IN GAMMA-RAY BURSTS  

SciTech Connect (OSTI)

The physical nature of gamma-ray bursts (GRBs) is believed to involve an ultra-relativistic jet. The observed complex structure of light curves motivates the idea of jet precession. In this work, we study the gravitational waves of jet precession based on neutrino-dominated accretion disks around black holes, which may account for the central engine of GRBs. In our model, the jet and the inner part of the disk may precess along with the black hole, which is driven by the outer part of the disk. Gravitational waves are therefore expected to be significant from this black-hole-inner-disk precession system. By comparing our numerical results with the sensitivity of some detectors, we find that it is possible for DECIGO and BBO to detect such gravitational waves, particularly for GRBs in the Local Group.

Sun Mouyuan; Liu Tong; Gu Weimin; Lu Jufu, E-mail: tongliu@xmu.edu.cn [Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China)

2012-06-10T23:59:59.000Z

402

Systematic Studies of Jet Quenching in Hot Nuclear Matter  

E-Print Network [OSTI]

??????????????????????????????..x CHAPTER I INTRODUCTION????????????????????????...1 Nuclear matter???????????????????????.1 The standard model of elementary particles??..?????????..1 Quark gluon plasma????????????.?????????3 Jet quenching... OF FIGURES FIGURE Page 1.1. Nuclear Matter Phase Transition Diagram????????????....................2 1.2. Colliding Particles Diagram...

Delgado, Andrea

2011-05-04T23:59:59.000Z

403

Jet Fragmentation in Medium and Vacuum with the PHENIX Detector  

E-Print Network [OSTI]

One of the most active areas of investigation in relativistic heavy-ion collisions is the study of the jet quenching phenomenon whereby hard partons lose their energy as they traverse the hot, dense matter created in such collisions. Strong parton energy loss has been observed in central nucleus-nucleus collisions as evidenced by the a large suppression of the yield of high pT hadrons as compared to the expected yield based on measurements in p+p collisions. Moreover, measurements of back-to-back correlations of charged hadrons suggest that jet shapes are strongly modified modified by the medium. The quantitative interpretation of single and di-hadron measurements is, however, complicated by the fact that the initial parton energy is unknown. A more informative measurement would be one in which the initial parton energy is known, allowing the determination of the fragmentation function, which may be effectively modified from its vacuum form by the presence of the medium. Two measurements in which the initial parton energy may be estimated are discussed in these proceedings: jet reconstruction and two- particle correlations using direct photons. Jet reconstruction in nuclear collisions is challenging due to the large background of soft particles, fluctuations of which give rise to fake jets. Direct photons can be used to estimate the initial parton energy of the recoil jet without recourse to jet reconstruction algorithms. However, such studies suffer from a smaller rate and the direct photon signal must be disentangled from a large background of decay photons. We present jet reconstruction results which use an algorithm suitable for a high multiplicity environment. We also present results of two-particle correlations using direct photons. These results are discussed in the context of medium modification to the fragmentation function.

Matthew Nguyen for the PHENIX Collaboration

2010-08-08T23:59:59.000Z

404

Pneumatic cleaning of sugarcane utilizing a high velocity air jet  

E-Print Network [OSTI]

- oped to cope with the increased amount of trash present in unburned sugarcane. This research involved the testing and computer simulation of a chopper air jet nozzle assembly. The experimental test setup included a two-stage conveyor. This conveyor... of the system was evaluated. The results of the chopper air jet nozzle assembly tests verified that the air velocity, nozzle size, chopper blade configuration and feed-in rate contributed signifi- cantly to the cleanliness of the billets. The air velo- city...

Fisher, John Ray

2012-06-07T23:59:59.000Z

405

Interaction of a Liquid Gallium Jet with ISTTOK Edge Plasmas  

SciTech Connect (OSTI)

The use of liquid metals as plasma facing components in tokamaks has recently experienced a renewed interest stimulated by their advantages in the development of a fusion reactor. Liquid metals have been proposed to solve problems related to the erosion and neutronic activation of solid walls submitted to high power loads allowing an efficient heat exhaust from fusion devices. Presently the most promising candidate materials are lithium and gallium. However, lithium has a short liquid state range when compared, for example, with gallium that has essentially better thermal properties and lower vapor pressure. To explore further these properties, ISTTOK tokamak is being used to test the interaction of a free flying, fully formed liquid gallium jet with the plasma. The interacting, 2.3 mm diameter, jet is generated by hydrostatic pressure and has a 2.5 m/s flow velocity. The liquid metal injector has been build to allow the positioning of the jet inside the tokamak chamber, within a 13 mm range. This paper presents the first obtained experimental results concerning the liquid gallium jet-plasma interaction. A stable jet has been obtained, which was not noticeably affected by the magnetic field transients. ISTTOK has been successfully operated with the gallium jet without degradation of the discharge or a significant plasma contamination by liquid metal. This observation is supported by spectroscopic measurements showing that gallium radiation is limited to the region around the jet. Furthermore, the power deposited on the jet has been evaluated at different radial locations and the surface temperature increase estimated.

Gomes, R. B.; Fernandes, H.; Silva, C.; Pereira, T.; Figueiredo, J.; Carvalho, B.; Soares, A.; Duarte, P.; Varandas, C. [Associacao EURATOM/IST, Centro de Fusao Nuclear, Av. Rovisco Pais, 1049-001 Lisboa, Porugal (Portugal); Sarakovskis, A.; Lielausis, O.; Klyukin, A.; Platacis, E.; Tale, I. [Association EURATOM/University of Latvia, Institute of Solid State Physics, 8 Kengaraga Str., LV-1063 Riga (Latvia)

2008-04-07T23:59:59.000Z

406

Drum drying of black liquor using superheated steam impinging jets  

SciTech Connect (OSTI)

A novel drum dryer for black liquor utilizing multiple impinging jets of superheated steam was designed and built to evaluate the performance characteristics and effects of various operating parameters thereon. Appropriate ranges of parameters such as steam jet temperature and velocity were examined experimentally to quantify the optimal operating conditions for the formation of black liquor film on the drum surface as well as the drying kinetics.

Shiravi, A.H.; Mujumdar, A.S.; Kubes, G.J. [McGill Univ., Montreal, Quebec (Canada)

1997-05-01T23:59:59.000Z

407

Jet plume injection and combustion system for internal combustion engines  

DOE Patents [OSTI]

An improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure.

Oppenheim, Antoni K. (Kensington, CA); Maxson, James A. (Berkeley, CA); Hensinger, David M. (Albany, CA)

1993-01-01T23:59:59.000Z

408

Transverse liquid fuel jet breakup, burning, and ignition  

SciTech Connect (OSTI)

An analytical/numerical study of the breakup, burning, and ignition of liquid fuels injected transversely into a hot air stream is conducted. The non-reacting liquid jet breakup location is determined by the local sonic point criterion first proposed by Schetz, et al. (1980). Two models, one employing analysis of an elliptical jet cross-section and the other employing a two-dimensional blunt body to represent the transverse jet, have been used for sonic point calculations. An auxiliary criterion based on surface tension stability is used as a separate means of determining the breakup location. For the reacting liquid jet problem, a diffusion flame supported by a one-step chemical reaction within the gaseous boundary layer is solved along the ellipse surface in subsonic crossflow. Typical flame structures and concentration profiles have been calculated for various locations along the jet cross-section as a function of upstream Mach numbers. The integrated reaction rate along the jet cross-section is used to predict ignition position, which is found to be situated near the stagnation point. While a multi-step reaction is needed to represent the ignition process more accurately, the present calculation does yield reasonable predictions concerning ignition along a curved surface.

Li, H.

1990-01-01T23:59:59.000Z

409

Transverse liquid fuel jet breakup, burning, and ignition  

SciTech Connect (OSTI)

An analytical/numerical study of the breakup, burning, and ignition of liquid fuels injected transversely into a hot air stream is conducted. The non-reacting liquid jet breakup location is determined by the local sonic point criterion first proposed by Schetz, et al. (1980). Two models, one employing analysis of an elliptical jet cross-section and the other employing a two-dimensional blunt body to represent the transverse jet, have been used for sonic point calculations. An auxiliary criterion based on surface tension stability is used as a separate means of determining the breakup location. For the reacting liquid jet problem, a diffusion flame supported by a one-step chemical reaction within the gaseous boundary layer is solved along the ellipse surface in subsonic crossflow. Typical flame structures and concentration profiles have been calculated for various locations along the jet cross-section as a function of upstream Mach numbers. The integrated reaction rate along the jet cross-section is used to predict ignition position, which is found to be situated near the stagnation point. While a multi-step reaction is needed to represent the ignition process more accurately, the present calculation does yield reasonable predictions concerning ignition along a curved surface.

Li, H.

1990-12-31T23:59:59.000Z

410

Measurements of Vector Bosons Produced in Association with Jets  

SciTech Connect (OSTI)

The latest D0 and CDF measurements of the W + jets and Z/{gamma}* + jets processes are described, along with a discussion of the comparisons that have been made to LO and NLO perturbative QCD predictions. The direct production of W{sup {+-}}/Z bosons in association with jets is a process of crucial importance at hadron collider experiments. The presence of a vector boson in the hard scatter means that these interactions occur at a scale that should make perturbative QCD applicable, and thus it is an excellent channel to test such predictions. Furthermore, many of the potential discovery channels for the Higgs boson and beyond standard model processes share a final state signature with the W{sup {+-}}/Z + jets process. It is thus vital for the success of existing and future hadron collider experiments that this process is understood, and recently there has been a huge amount of work put into the modeling of this process, with the appearance of many new Monte Carlo generators that are already widely used at both the Tevatron and LHC. In Sections 2 and 3 the latest W + jets and Z/{gamma}* + jets measurements from the Tevatron are presented, and in Section 4 we discuss the results and implications of some of the theory comparisons that have thus far been made.

Cooper, Ben; /University Coll. London

2008-07-01T23:59:59.000Z

411

Jet plume injection and combustion system for internal combustion engines  

DOE Patents [OSTI]

An improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure. 24 figures.

Oppenheim, A.K.; Maxson, J.A.; Hensinger, D.M.

1993-12-21T23:59:59.000Z

412

An overview of the Nuclear Electric Propulsion Space Test Program (NEPSTP) satellite  

SciTech Connect (OSTI)

Early in 1992 the idea of purchasing a Russian designed and fabricated space reactor power system and integrating it with a US designed satellite went from fiction to reality with the purchase of the first two Topaz II reactors by the Strategic Defense Initiative Organization (now the Ballistic Missile Defense Organization (BMDO). The New Mexico Alliance was formed to establish a ground test facility in which to perform nonnuclear systems testing of the Topaz II, and to evaluate the Topaz 11 system for flight testing with respect to safety, performance, and operability. In conjunction, SDIO requested that the Applied Physics Laboratory in Laurel, MD propose a mission and design a satellite in which the Topaz II could be used as the power source. The outcome of these two activities was the design of the Nuclear Electric Propulsion Space Test Program (NEPSTP) satellite which combines a modified Russian Topaz II power system with a US designed satellite to achieve a specified mission. Due to funding reduction within the SDIO, the Topaz II flight program was postponed indefinitely at the end of Fiscal Year 1993. The purpose of this paper is to present an overview of the NEPSTP mission and the satellite design at the time the flight program ended.

Voss, S.S. [Los Alamos National Lab., NM (United States); Reynolds, E.L. [Applied Physics Laboratory, Laurel, MD (United States)

1994-06-01T23:59:59.000Z

413

Heat pipe radiation cooling (HPRC) for high-speed aircraft propulsion. Phase 2 (feasibility) final report  

SciTech Connect (OSTI)

The National Aeronautics and Space Administration (NASA), Los Alamos National Laboratory (Los Alamos), and CCS Associates are conducting the Heat Pipe Radiation Cooling (HPRC) for High-Speed Aircraft Propulsion program to determine the advantages and demonstrate the feasibility of using high-temperature heat pipes to cool hypersonic engine components. This innovative approach involves using heat pipes to transport heat away from the combustor, nozzle, or inlet regions, and to reject it to the environment by thermal radiation from adjacent external surfaces. HPRC is viewed as an alternative (or complementary) cooling technique to the use of pumped cryogenic or endothermic fuels to provide regenerative fuel or air cooling of the hot surfaces. The HPRC program has been conducted through two phases, an applications phase and a feasibility phase. The applications program (Phase 1) included concept and assessment analyses using hypersonic engine data obtained from US engine company contacts. The applications phase culminated with planning for experimental verification of the HPRC concept to be pursued in a feasibility program. The feasibility program (Phase 2), recently completed and summarized in this report, involved both analytical and experimental studies.

Martin, R.A.; Merrigan, M.A.; Elder, M.G.; Sena, J.T.; Keddy, E.S. [Los Alamos National Lab., NM (United States); Silverstein, C.C. [CCS Associates, Bethel Park, PA (United States)

1994-03-25T23:59:59.000Z

414

Feasibility study of a nonequilibrium MHD accelerator concept for hypersonic propulsion ground testing  

SciTech Connect (OSTI)

A National Aeronautics and Space Administration (NASA) funded research study to evaluate the feasibility of using magnetohydrodynamic (MHD) body force accelerators to produce true air simulation for hypersonic propulsion ground testing is discussed in this paper. Testing over the airbreathing portion of a transatmospheric vehicle (TAV) hypersonic flight regime will require high quality air simulation for actual flight conditions behind a bow shock wave (forebody, pre-inlet region) for flight velocities up to Mach 16 and perhaps beyond. Material limits and chemical dissociation at high temperature limit the simulated flight Mach numbers in conventional facilities to less than Mach 12 for continuous and semi-continuous testing and less than Mach 7 for applications requiring true air chemistry. By adding kinetic energy directly to the flow, MHD accelerators avoid the high temperatures and pressures required in the reservoir region of conventional expansion facilities, allowing MHD to produce true flight conditions in flight regimes impossible with conventional facilities. The present study is intended to resolve some of the critical technical issues related to the operation of MHD at high pressure. Funding has been provided only for the first phase of a three to four year feasibility study that would culminate in the demonstration of MHD acceleration under conditions required to produce true flight conditions behind a bow shock wave to flight Mach numbers of 16 or greater. MHD critical issues and a program plan to resolve these are discussed.

Lee, Ying-Ming; Simmons, G.A.; Nelson, G.L. [MSE Inc., Butte, MT (United States)

1995-12-31T23:59:59.000Z

415

Flyer Acceleration by Pulsed Ion Beam Ablation and Application for Space Propulsion  

SciTech Connect (OSTI)

Flyer acceleration by ablation plasma pressure produced by irradiation of intense pulsed ion beam has been studied. Acceleration process including expansion of ablation plasma was simulated based on fluid model. And interaction between incident pulsed ion beam and a flyer target was considered as accounting stopping power of it. In experiments, we used ETIGO-II intense pulsed ion beam generator with two kinds of diodes; 1) Magnetically Insulated Diode (MID, power densities of <100 J/cm2) and 2) Spherical-focused Plasma Focus Diode (SPFD, power densities of up to 4.3 kJ/cm2). Numerical results of accelerated flyer velocity agreed well with measured one over wide range of incident ion beam energy density. Flyer velocity of 5.6 km/s and ablation plasma pressure of 15 GPa was demonstrated by the present experiments. Acceleration of double-layer target consists of gold/aluminum was studied. For adequate layer thickness, such a flyer target could be much more accelerated than a single layer. Effect of waveform of ion beam was also examined. Parabolic waveform could accelerate more efficiently than rectangular waveform. Applicability of ablation propulsion was discussed. Specific impulse of 7000{approx}8000 seconds and time averaged thrust of up to 5000{approx}6000N can be expected. Their values can be controllable by changing power density of incident ion beam and pulse duration.

Harada, Nobuhiro; Buttapeng, Chainarong; Yazawa, Masaru [Department of Electrical Engineering, Nagaoka University of Technology, 1603 Kamitomioka, Nagaoka 940-2188 (Japan); Kashine, Kenji [Department of Electrical and Electronic Engineering, Kagoshima National College of Technology, 1460-1 Shinko, Hayato-cho, Aira-gun, Kagoshima 899-5193 (Japan); Jiang Weihua; Yatsui, Kiyoshi [Extreme Energy Density Research Institute, Nagaoka University of Technology, 1603 Kamitomioka, Nagaoka 940-2188 (Japan)

2004-02-04T23:59:59.000Z

416

The microwave electro-thermal (MET) thruster: A new technology for satellite propulsion and attitude control  

SciTech Connect (OSTI)

This paper discusses the current research status of the MET (Microwave Electro-Thermal) thruster. In the MET thruster, an electrodeless, vortex stabilized, plasma is produced in a microwave resonator cavity for the purpose of heating gaseous fuel to produce a high temperature rocket exhaust for space propulsion. The higher specific impulse (momentum transfer per unit weight) of these heated gases offers advantages over traditional chemical rockets in terms of reduced fuel mass. In MET devices, dense plasmas have been produced in various possible fuel gases, nitrogen, hydrogen, and ammonia, using 600 to 2200 Watts of microwave power at a frequency of 2.45 GHz. Ammonia has been found to give a specific impulse of 550 sec. It has been found that the plasma is a 98{percent} absorber of microwave power leading to negligible reflection of power back to the microwave source and making the cavity operate at low {ital Q}. Taking advantage of this effect, it has been found that a very compact MET thruster design could be operated, with the magnetron microwave source and resonator cavity joined in one unit. The MET can run at a variety of power levels and use many fuels, including H{sub 2}O. {copyright} {ital 1996 American Institute of Physics.}

Brandenburg, J.E. [Principle Research Scientist, Research Support Instruments, Washington Operations, 4325-B Forbes Boulevard, Lanham, Maryland 20706 (United States); Micci, M.M. [Assoc. Professor of Aerospace Eng., Propulsion Engineering Research Center, Department of Aerospace Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

1996-03-01T23:59:59.000Z

417

Rocketdyne Propulsion and Power DOE Operations annual site environmental report 1997  

SciTech Connect (OSTI)

This annual report discusses environmental monitoring at two manufacturing and test sites operated in the Los Angeles area by Rocketdyne Propulsion and Power of Boeing North American, Inc. These are identified as Area 4 of the SSFL and the De Soto site. These sites have been used for research and development (R and D), engineering, and testing in a broad range of technical fields primarily in energy research and nuclear reactor technology. The De Soto site had research and development laboratories involved with nuclear research. This work was terminated in 1995 and only D and D activities will have potential for impact on the environment. Since 1956, Area 4 has been used for work with nuclear materials, including fabricating nuclear reactor fuels, testing nuclear reactors, and dissembling used fuel elements. This work ended in 1988 and subsequent efforts have been directed toward decommissioning and decontamination of the former nuclear facilities. The primary purpose of this report is to present information on environmental and effluent monitoring of DOE-sponsored activities to the regulatory agencies responsible for oversight. Information presented here concentrates on Area 4 at SSFL, which is the only area at SSFL where DOE operations were performed.

Robinson, K.S. [ed.

1998-11-23T23:59:59.000Z

418

Multiple pole electromagnetic propulsion system with separated ballistic guidance and electrical current contact surfaces  

DOE Patents [OSTI]

An electromagnetic propulsion system is disclosed having separate rails for ballistic guidance and for carrying current. In this system, one or more pairs of ballistic guidance rails are provided, with each ballistic guidance rail having a pair of current carrying rails joined to it to form a combined rail. Each combined rail is separated electrically from adjacent combined rails by electrically insulating blocks. Each of the current carrying rails in a given combined rail pair have the same electrical polarity, and the polarities alternate between adjacent combined rails. Armatures contact current carrying rails to complete the circuit to generate the accelerating Lorentz force on the armatures. Bore riders on the sabot and/or projectile are in contact with the ballistic guide rails. Separation of the current carrying and ballistic guidance functions increases resistance of the system to rail movement and bending, as well as reduced wear/damage to the rails. In further embodiments, a circumferential over wrap providing compressive force on the rails further increases resistance of the system to rail movement and bending.

Sims, Jr., James R. (Los Alamos, NM)

2008-07-15T23:59:59.000Z

419

Airbreathing Laser Propulsion Experiments with 1 {mu}m Terawatt Pharos IIILaser: Part 2  

SciTech Connect (OSTI)

This basic research study examines the physics of airbreathing laser propulsion at the extreme flux range of 1-2x10{sup 11} W/cm{sup 2}--within the air breakdown threshold for l {mu}m radiation--using the terawatt Pharos III neodymium-glass pulsed laser. Six different experimental setups were employed using a 34 mm line focus with 66 {mu}m focal waist, positioned near the flat impulse surface. The 2nd Campaign investigated impulse generation with the laser beam focused at grazing incidence across near horizontal target surfaces, with pulse energies ranging from 55 to 186 J, and pulse-widths of 2 to 30 ns FWHM. Laser generated impulse was measured with a horizontal Plexiglas registered ballistic pendulum equipped with either a steel target insert or 0.5 Tesla permanent magnet (NEIT-40), to quantify changes in the momentum coupling coefficient (C{sub M}). Part 2 of this 2-part paper covers Campaign no. 2 results including C{sub M} performance data, and long exposure color photos of LP plasma phenomena.

Myrabo, L. N.; Lyons, P. W.; Jones, R. A.; Liu, S. [Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Manka, C. [Space Plasma Branch, Plasma Physics Division, Naval Research Laboratory, Washington, D.C. (United States)

2011-11-10T23:59:59.000Z

420

Heavy Vehicle Propulsion System Materials Program semiannual progress report for October 1996 through March 1997  

SciTech Connect (OSTI)

The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks. The design of advanced components for high-efficiency diesel engines has, in some cases, pushed the performance envelope for materials of construction past the point of reliable operation. Higher mechanical and tribological stresses and higher temperatures of advanced designs limit the engine designers; advanced materials allow the design of components that may operate reliably at higher stresses and temperatures, thus enabling more efficient engine designs. Advanced materials also offer the opportunity to improve the emissions, NVH, and performance of diesel engines for pickup trucks, vans, and sport utility vehicles. The principal areas of research are: (1) cost effective high performance materials and processing; (2) advanced manufacturing technology; (3) testing and characterization; and (4) materials and testing standards.

NONE

1997-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Tank-treading as a means of propulsion in viscous shear flows  

E-Print Network [OSTI]

The use of tank-treading as a means of propulsion for microswimmers in viscous shear flows is taken into exam. We discuss the possibility that a vesicle be able to control the drift in an external shear flow, by varying locally the bending rigidity of its own membrane. By analytical calculation in the quasi-spherical limit, the stationary shape and the orientation of the tank-treading vesicle in the external flow, are determined, working to lowest order in the membrane inhomogeneity. The membrane inhomogeneity acts in the shape evolution equation as an additional force term, that can be used to balance the effect of the hydrodynamic stresses, thus allowing the vesicle to assume shapes and orientations that would otherwise be forbidden. The vesicle shapes and orientations required for migration transverse to the flow, together with the bending rigidity profiles that would lead to such shapes and orientations, are determined. A simple model is presented, in which a vesicle is able to migrate up or down the gradient of a concentration field, by stiffening or softening of its membrane, in response to the variations in the concentration level experienced during tank-treading.

Piero Olla

2011-07-19T23:59:59.000Z

422

Search for anomalous production of events with a photon, jet, b-quark jet, and missing transverse energy  

E-Print Network [OSTI]

We present a signature-based search for the anomalous production of events containing a photon, two jets, of which at least one is identified as originating from a b quark, and missing transverse energy (E?[subscript T]). ...

Xie, Si

423

Pulse Jet Mixing Tests With Noncohesive Solids  

SciTech Connect (OSTI)

This report summarizes results from pulse jet mixing (PJM) tests with noncohesive solids in Newtonian liquid conducted during FY 2007 and 2008 to support the design of mixing systems for the Hanford Waste Treatment and Immobilization Plant (WTP). Tests were conducted at three geometric scales using noncohesive simulants. The test data were used to independently develop mixing models that can be used to predict full-scale WTP vessel performance and to rate current WTP mixing system designs against two specific performance requirements. One requirement is to ensure that all solids have been disturbed during the mixing action, which is important to release gas from the solids. The second requirement is to maintain a suspended solids concentration below 20 weight percent at the pump inlet. The models predict the height to which solids will be lifted by the PJM action, and the minimum velocity needed to ensure all solids have been lifted from the floor. From the cloud height estimate we can calculate the concentration of solids at the pump inlet. The velocity needed to lift the solids is slightly more demanding than "disturbing" the solids, and is used as a surrogate for this metric. We applied the models to assess WTP mixing vessel performance with respect to the two perform¬ance requirements. Each mixing vessel was evaluated against these two criteria for two defined waste conditions. One of the wastes was defined by design limits and one was derived from Hanford waste characterization reports. The assessment predicts that three vessel types will satisfy the design criteria for all conditions evaluated. Seven vessel types will not satisfy the performance criteria used for any of the conditions evaluated. The remaining three vessel types provide varying assessments when the different particle characteristics are evaluated. The assessment predicts that three vessel types will satisfy the design criteria for all conditions evaluated. Seven vessel types will not satisfy the performance criteria used for any of the conditions evaluated. The remaining three vessel types provide varying assessments when the different particle characteristics are evaluated. The HLP-022 vessel was also evaluated using 12 m/s pulse jet velocity with 6-in. nozzles, and this design also did not satisfy the criteria for all of the conditions evaluated.

Meyer, Perry A.; Bamberger, Judith A.; Enderlin, Carl W.; Fort, James A.; Wells, Beric E.; Sundaram, S. K.; Scott, Paul A.; Minette, Michael J.; Smith, Gary L.; Burns, Carolyn A.; Greenwood, Margaret S.; Morgen, Gerald P.; Baer, Ellen BK; Snyder, Sandra F.; White, Michael; Piepel, Gregory F.; Amidan, Brett G.; Heredia-Langner, Alejandro; Bailey, Sharon A.; Bower, John C.; Denslow, Kayte M.; Eakin, David E.; Elmore, Monte R.; Gauglitz, Phillip A.; Guzman, Anthony D.; Hatchell, Brian K.; Hopkins, Derek F.; Hurley, David E.; Johnson, Michael D.; Kirihara, Leslie J.; Lawler, Bruce D.; Loveland, Jesse S.; Mullen, O Dennis; Pekour, Mikhail S.; Peters, Timothy J.; Robinson, Peter J.; Russcher, Michael S.; Sande, Susan; Santoso, Christian; Shoemaker, Steven V.; Silva, Steve M.; Smith, Devin E.; Su, Yin-Fong; Toth, James J.; Wiberg, John D.; Yu, Xiao-Ying; Zuljevic, Nino

2009-05-11T23:59:59.000Z

424

Measurement of the ratio of the 3-jet to 2-jet cross sections in pp collisions at ?s = 7 TeV  

E-Print Network [OSTI]

A measurement of the ratio of the inclusive 3-jet to 2-jet cross sections as a function of the total jet transverse momentum, HT, in the range 0.2

Wyslouch, Boleslaw

425

A study of jet energy measurement at CDF  

SciTech Connect (OSTI)

This thesis describes the effort being made to improve the Jet Energy Reconstruction as performed by the CDF international collaboration at the Tevatron collider. This experiment studies proton-antiproton interactions at a center of mass energy of 1.8 TeV. During the three years data taking period Run 1, from 1992 to 1995 the CDF experiment collected an amount of data corresponding to a total integrated luminosity of 110 pb{sup -1}. One of the major results obtained analyzing this data sample is the discovery of the top quark. In the year 2000 a new period of data taking, Run 11, will start with a higher luminosity and a slightly higher center of mass energy giving us the chance to explore high energy physics even deeper. In preparation of this new run several upgrades are being made to adapt the CDF detector to the high luminosity foreseen and to improve its capabilities. Many signatures requested to trigger the detector aim at signaling a quark or a gluon in the final state. Unfortunately we are not able to measure quarks as free particles because they undergo a fragmentation process when turning into jets of particles. Thus it is of key importance to build up algorithms which reconstruct the energy of the initial parton starting from the jet informations. The description of the algorithm adopted till now will be given as an introduction to the new method being developed, that will be the main subject of this thesis. In Chapter I we will give a theoretical introduction on strong interactions to describe the mechanism to produce hadronic jets. In Chapter 2 we will describe some results from the experiment where the reconstruction of hadronic jets was important. Here we will also mention some important results which we think we can obtain during new the data taking period. We will give particular emphasis to those processes where an improved jet energy measured would bring to better results. In Chapter 3 we will give a description of the CDF detector including some more details on the elements which are relevant for jet energy reconstruction. The way of defining jets which has been used by CDF so far, will be the subject of chapter 4. Starting from the present CDF algorithm we studied the various problems which arise with jet reconstruction. Those problems can be grouped into two categories, the one including effects coming from physics and a second one including the effects due to a non-perfect resolution of our detector. In Chapter 5 the physics effects limiting jet energy reconstruction will be addressed. We will discuss the radiation of hard gluons both from initial state and final state partons and we will show how these problems are connected with jet definition algorithms. In Chapter 6 we will describe a new method to define jet energy making use of some detector informations which are not used in the present algorithm. The energy of each single calorimeter tower will be re-defined taking into account not only the energy released in the calorimeters, but also the informations on the shower development through it and the tracking informations coming from the Central Tracking Chamber. Finally, in Chapter 7 we apply the studies described above on photon+jet events collected during the run 1. The use of data is of key importance to claim that our corrections are working fine. We will show how a 30 % improvement in jet energy resolution, a major step towards better jet physics in Run 11, is obtained.

NONE

1998-09-01T23:59:59.000Z

426

Dynamics and Structure of Three-Dimensional Poloidally Magnetized Supermagnetosonic Jets  

E-Print Network [OSTI]

A set of 3D MHD simulations of magnetized jets has been performed. The jets contain an equipartition primarily poloidal magnetic field and the effect of jet density on jet dynamics and structure is evaluated. The jet is precessed at the origin to excite Kelvin-Helmholtz unstable helical modes. We extensively compare the structure in these simulations with linear stability theory. The jet that is dense with respect to the external medium develops a high speed core surrounded by a less dense sheath consisting of slower moving jet fluid. These simulations suggest that extended extragalactic jets propagate to such large distances because they are surrounded by a lobe or cocoon whose density is less than the jet density. (Abridged abstract.)

P. E. Hardee; D. A. Clarke; A. Rosen

1997-03-16T23:59:59.000Z

427

A Mechanism for Coronal Hole Jets  

E-Print Network [OSTI]

Bald patches are magnetic topologies in which the magnetic field is concave up over part of a photospheric polarity inversion line. A bald patch topology is believed to be the essential ingredient for filament channels and is often found in extrapolations of the observed photospheric field. Using an analytic source-surface model to calculate the magnetic topology of a small bipolar region embedded in a global magnetic dipole field, we demonstrate that although common in closed-field regions close to the solar equator, bald patches are unlikely to occur in the open-field topology of a coronal hole. Our results give rise to the following question: What happens to a bald patch topology when the surrounding field lines open up? This would be the case when a bald patch moves into a coronal hole, or when a coronal hole forms in an area that encompasses a bald patch. Our magnetostatic models show that, in this case, the bald patch topology almost invariably transforms into a null point topology with a spine and a fan. We argue that the time-dependent evolution of this scenario will be very dynamic since the change from a bald patch to null point topology cannot occur via a simple ideal evolution in the corona. We discuss the implications of these findings for recent Hinode XRT observations of coronal hole jets and give an outline of planned time-dependent 3D MHD simulations to fully assess this scenario.

D. A. N. Mueller; S. K. Antiochos

2008-04-24T23:59:59.000Z

428

Spectrometric Analysis for Pulse Jet Mixer Testing  

SciTech Connect (OSTI)

The Analytical Development Section (ADS) was tasked with providing support for a Hanford River Protection Program-Waste Treatment Program (RPP-WTP) project test involving absorption analysis for non-Newtonian pulse jet mixer testing for small scale (PJM) and prototype (CRV) tanks with sparging. Tanks filled with clay were mixed with various amounts of powdered dye as a tracer. The objective of the entire project was to determine the best mixing protocol (nozzle velocity, number of spargers used, total air flow, etc.) by determining the percent mixed volume through the use of an ultraviolet-visible (UV-Vis) spectrometer. The dye concentration within the sample could be correlated to the volume fraction mixed in the tank. Samples were received in vials, a series of dilutions were generated from the clay, allowed to equilibrate, then centrifuged and siphoned for the supernate liquid to analyze by absorption spectroscopy. Equilibration of the samples and thorough mixing of the samples were a continuous issue with dilution curves being difficult to obtain. Despite these technical issues, useful data was obtained for evaluation of various mix conditions.

ZEIGLER, KRISTINE

2004-07-12T23:59:59.000Z

429

Measurement of the inclusive production cross sections for forward jets and for dijet events with one forward and one central jet in pp collisions at ?s = 7 TeV  

E-Print Network [OSTI]

The inclusive production cross sections for forward jets, as well for jets in dijet events with at least one jet emitted at central and the other at forward pseudorapidities, are measured in the range of transverse momenta ...

Alver, B.

430

A 'BOOSTED FIREBALL' MODEL FOR STRUCTURED RELATIVISTIC JETS  

SciTech Connect (OSTI)

We present a model for relativistic jets which generates a particular angular distribution of Lorentz factor and energy per solid angle. We consider a fireball with specific internal energy E/M launched with bulk Lorentz factor ? {sub B}. In its center-of-momentum frame the fireball expands isotropically, converting its internal energy into radially expanding flow with asymptotic Lorentz factor ?{sub 0} ? E/M. In the lab frame the flow is beamed, expanding with Lorentz factor ? = 2?{sub 0}? {sub B} in the direction of its initial bulk motion and with characteristic opening angle ?{sub 0} ? 1/? {sub B}. The flow is jet-like with ??{sub 0} ? 2?{sub 0} such that jets with ? > 1/?{sub 0} are naturally produced. The choice ?{sub 0} ? ? {sub B} ? 10 yields a jet with ? ? 200 on-axis and angular structure characterized by opening angle ?{sub 0} ? 0.1 of relevance for cosmological gamma-ray bursts (GRBs), while ? {sub B} ?> 1 may be relevant for low-luminosity GRBs. The model produces a family of outflows, of relevance for different relativistic phenomena with structures completely determined by ?{sub 0} and ? {sub B}. We calculate the energy per unit solid angle for the model and use it to compute light curves for comparison with the widely used top-hat model. The jet break in the boosted fireball light curve is greatly subdued when compared to the top-hat model because the edge of the jet is smoother than for a top-hat. This may explain missing jet breaks in afterglow light curves.

Duffell, Paul C.; MacFadyen, Andrew I., E-mail: pcd233@nyu.edu, E-mail: macfadyen@nyu.edu [Center for Cosmology and Particle Physics, New York University, NY (United States)

2013-10-10T23:59:59.000Z

431

P. Jordan,A. Arnscheidt, H. McGrogan and S. McCormick Hydrol. Earth Syst. Sci., 11(1), 372381, 2007  

E-Print Network [OSTI]

eutrophic impact on the river system. In large catchments, wastewater treatment works are likely Commons License. Characterising phosphorus transfers in rural catchments using a continuous bank

Boyer, Edmond

432

Pulse Jet Mixing Tests With Noncohesive Solids  

SciTech Connect (OSTI)

This report summarizes results from pulse jet mixing (PJM) tests with noncohesive solids in Newtonian liquid. The tests were conducted during FY 2007 and 2008 to support the design of mixing systems for the Hanford Waste Treatment and Immobilization Plant (WTP). Tests were conducted at three geometric scales using noncohesive simulants, and the test data were used to develop models predicting two measures of mixing performance for full-scale WTP vessels. The models predict the cloud height (the height to which solids will be lifted by the PJM action) and the critical suspension velocity (the minimum velocity needed to ensure all solids are suspended off the floor, though not fully mixed). From the cloud height, the concentration of solids at the pump inlet can be estimated. The predicted critical suspension velocity for lifting all solids is not precisely the same as the mixing requirement for 'disturbing' a sufficient volume of solids, but the values will be similar and closely related. These predictive models were successfully benchmarked against larger scale tests and compared well with results from computational fluid dynamics simulations. The application of the models to assess mixing in WTP vessels is illustrated in examples for 13 distinct designs and selected operational conditions. The values selected for these examples are not final; thus, the estimates of performance should not be interpreted as final conclusions of design adequacy or inadequacy. However, this work does reveal that several vessels may require adjustments to design, operating features, or waste feed properties to ensure confidence in operation. The models described in this report will prove to be valuable engineering tools to evaluate options as designs are finalized for the WTP. Revision 1 refines data sets used for model development and summarizes models developed since the completion of Revision 0.

Meyer, Perry A.; Bamberger, Judith A.; Enderlin, Carl W.; Fort, James A.; Wells, Beric E.; Sundaram, S. K.; Scott, Paul A.; Minette, Michael J.; Smith, Gary L.; Burns, Carolyn A.; Greenwood, Margaret S.; Morgen, Gerald P.; Baer, Ellen BK; Snyder, Sandra F.; White, Michael K.; Piepel, Gregory F.; Amidan, Brett G.; Heredia-Langner, Alejandro

2012-02-17T23:59:59.000Z

433

Simulations of Evolving or Outbursting Molecular Protostellar Jets  

E-Print Network [OSTI]

The kinematic and radiative power of molecular jets is expected to change as a protostar undergoes permanent or episodal changes in the rate at which it accretes. We study here the consequences of evolving jet power on the spatial and velocity structure, as well as the fluxes, of molecular emission from the bipolar outflow. We consider a jet of rapidly increasing density and a jet in which the mass input is abruptly cut off. We perform three dimensional hydrodynamic simulations with atomic and molecular cooling and chemistry. In this work, highly collimated and sheared jets are assumed. We find that position-velocity diagrams, velocity-channel maps and the relative H$_2$ and CO fluxes are potentially the best indicators of the evolutionary stage. In particular, the velocity width of the CO lines may prove most reliable although the often-quoted mass-velocity power-law index is probably not. We demonstrate how the relative H$_2$ 1--0 S(1) and CO J=1--0 fluxes evolve and apply this to interpret the phase of several outflows.

Alexander Rosen; Michael D. Smith

2003-04-25T23:59:59.000Z

434

Implementation and Performance of the ATLAS Second Level Jet Trigger  

E-Print Network [OSTI]

ATLAS is one of the four major LHC experiments, designed to cover a wide range of physics topics. In order to cope with a rate of 40 MHz and 25 interactions per bunch crossing, the ATLAS trigger system is divided in three different levels. The first one (LVL1, hardware based) identifies signatures in 2 microseconds that are confirmed by the the following trigger levels (software based). The Second Level Trigger (LVL2) only looks at a region of the space around the LVL1 signature (called Region of Interest or ROI), confirming/rejecting the event in about 10 ms, while the Event Filter (Third Level Trigger, EF) has potential full event access and larger processing times, of the order of 1 s. The jet selection starts at the LVL1 with dedicated processors that search for high ET hadronic energy depositions. At the LVL2, the jet signatures are verified with the execution of a dedicated, fast jet reconstruction algorithm. Given the fact that the main jet's background are jets,the energy calibration at the LVL2 is on...

Conde-Muíño, P; Brelier, B; Cranmer, K; Delsart, P A; Dufour, M A; Eckweiler, S; Ferland, J; Idarraga, J; Johns, K; LeCompte, T; Potter, C; Robertson, S; Santamarina-Rios, C; Segura, E; Silverstein, D; Vachon, B; International Conference on Computing in High Energy and Nuclear Physics

2008-01-01T23:59:59.000Z

435

Jet conversions in a quark-gluon plasma  

E-Print Network [OSTI]

Quark and gluon jets traversing through a quark-gluon plasma not only lose their energies but also can undergo flavor conversions. The conversion rates via the elastic $q(\\bar q)g\\to gq(\\bar q)$ and the inelastic $q\\bar q\\leftrightarrow gg$ scatterings are evaluated in the lowest order in QCD. Including both jet energy loss and conversions in the expanding quark-gluon plasma produced in relativistic heavy ion collisions, we have found a net conversion of quark to gluon jets. This reduces the difference between the nuclear modification factors for quark and gluon jets in central heavy ion collisions and thus enhances the $p/\\pi^+$ and ${\\bar p}/\\pi^-$ ratios at high transverse momentum. However, a much larger net quark to gluon jet conversion rate than the one given by the lowest-order QCD is needed to account for the observed similar ratios in central Au+Au and p+p collisions at same energy. Implications of our results are discussed.

W. Liu; C. M. Ko; B. W. Zhang

2007-05-05T23:59:59.000Z

436

Operations of a Radioisotope-based Propulsion System Enabling CubeSat Exploration of the Outer Planets  

SciTech Connect (OSTI)

Exploration to the outer planets is an ongoing endeavor but in the current economical environment, cost reduction is the forefront of all concern. The success of small satellites such as CubeSats launched to Near-Earth Orbit has lead to examine their potential use to achieve cheaper science for deep space applications. However, to achieve lower cost missions; hardware, launch and operations costs must be minimized. Additionally, as we push towards smaller exploration beds with relative limited power sources, allowing for adequate communication back to Earth is imperative. Researchers at the Center for Space Nuclear Research are developing the potential of utilizing an advanced, radioisotope-based system. This system will be capable of providing both the propulsion power needed to reach the destination and the additional requirements needed to maintain communication while at location. Presented here are a basic trajectory analysis, communication link budget and concept of operations of a dual-mode (thermal and electric) radioisotope-based propulsion system, for a proposed mission to Enceladus (Saturnian icy moon) using a 6U CubeSat payload. The radioisotope system being proposed will be the integration of three sub-systems working together to achieve the overall mission. At the core of the system, stored thermal energy from radioisotope decay is transferred to a passing propellant to achieve high thrust – useful for quick orbital maneuvering. An auxiliary closed-loop Brayton cycle can be operated in parallel to the thrusting mode to provide short bursts of high power for high data-rate communications back to Earth. Additionally, a thermal photovoltaic (TPV) energy conversion system will use radiation heat losses from the core. This in turn can provide the electrical energy needed to utilize the efficiency of ion propulsion to achieve quick interplanetary transit times. The intelligent operation to handle all functions of this system under optimized conditions adds to the complexity of the mission architecture.

Dr. Steven Howe; Nathan Jerred; Troy Howe; Adarsh Rajguru

2014-05-01T23:59:59.000Z

437

Designing a low cost XY stage for abrasive water jet cutting  

E-Print Network [OSTI]

This thesis guides the reader through the design of an inexpensive XY stage for abrasive water jet cutting machine starting with a set of functional requirements and ending with a product. Abrasive water jet cutting allows ...

Abu Ibrahim, Fadi, 1980-

2004-01-01T23:59:59.000Z

438

MODELING AND ANALYSIS OF CHEMILUMINESCENCE SENSING FOR SYNGAS, METHANE AND JET-A COMBUSTION  

E-Print Network [OSTI]

MODELING AND ANALYSIS OF CHEMILUMINESCENCE SENSING FOR SYNGAS, METHANE AND JET-A COMBUSTION of Technology August 2008 #12;MODELING AND ANALYSIS OF CHEMILUMINESCENCE SENSING FOR SYNGAS, METHANE AND JET

Seitzman, Jerry M.

439

Gas jet disruption mitigation studies on Alcator C-Mod and DIII-D  

E-Print Network [OSTI]

High-pressure noble gas jet injection is a mitigation technique which potentially satisfies the requirements of fast response time and reliability, without degrading subsequent discharges. Previously reported gas jet ...

Hollmann, E. M.

440

E-Print Network 3.0 - active molecular jets Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

7.1 Jet & protostar statistics in Orion A Summary: of Class I driven flows (for comparison, Gomez et al. 1997 found jets from 60 molecular outflows from... will be a major...

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Jet Production in ep Collisions at Low Q^2 and Determination of $\\alpha_{s}$  

E-Print Network [OSTI]

The production of jets is studied in deep-inelastic e+p scattering at low negative four momentum transfer squared 5jet, 2-jet and 3-jet cross sections as well as the ratio of 3-jet to 2-jet cross sections are measured as a function of Q^2 and jet transverse momentum. The 2-jet cross section is also measured as a function of the proton momentum fraction xi. The measurements are well described by perturbative quantum chromodynamics at next-to-leading order corrected for hadronisation effects and are subsequently used to extract the strong coupling alpha_s.

Aaron, FD; Alexa, C; Andreev, V; Antunovic, B; Backovic, S; Baghdasaryan, A; Barrelet, E; Bartel, W; Begzsuren, K; Belousov, A; Bizot, J C; Boudry, V; Bozovic-Jelisavcic, I; Bracinik, J; Brandt, G; Brinkmann, M; Brisson, V; Bruncko, D; Bunyatyan, A; Buschhorn, G; Bystritskaya, L; Campbell, A J; Cantun Avila, K B; Cerny, K; Cerny, V; Chekelian, V; Cholewa, A; Contreras, J G; Coughlan, J A; Cozzika, G; Cvach, J; Dainton, J B; Daum, K; Deak, M; Delcourt, B; Delvax, J; De Wolf, E A; Diaconu, C; Dodonov, V; Dossanov, A; Dubak, A; Eckerlin, G; Efremenko, V; Egli, S; Eliseev, A; Elsen, E; Falkiewicz, A; Favart, L; Fedotov, A; Felst, R; Feltesse, J; Ferencei, J; Fischer, D J; Fleischer, M; Fomenko, A; Gabathuler, E; Gayler, J; Ghazaryan, Samvel; Glazov, A; Glushkov, I; Goerlich, L; Gogitidze, N; Gouzevitch, M; Grab, C; Greenshaw, T; Grell, B R; Grindhammer, G; Habib, S; Haidt, D; Helebrant, C; Henderson, R C W; Hennekemper, E; Henschel, H; Herbst, M; Herrera, G; Hildebrandt, M; Hiller, K H; Hoffmann, D; Horisberger, R; Hreus, T; Jacquet, M; Janssen, X; Jonsson, L; Jung, A W; Jung, H; Kapichine, M; Katzy, J; Kenyon, I R; Kiesling, C; Klein, M; Kleinwort, C; Kluge, T; Knutsson, A; Kogler, R; Kosior, E; Kostka, P; Kraemer, M; Krastev, K; Kretzschmar, J; Kropivnitskaya, A; Kruger, K; Kutak, K; Landon, M P J; Lange, W; Lastovicka-Medin, G; Laycock, P; Lebedev, A; Lendermann, V; Levonian, S; Li, G; Lipka, K; Liptaj, A; List, B; List, J; Loktionova, N; Lopez-Fernandez, R; Lubimov, V; Makankine, A; Malinovski, E; Marage, P; Marti, Ll; Martyn, H U; Maxfield, S J; Mehta, A; Meyer, A B; Meyer, H; Meyer, H; Meyer, J; Mikocki, S; Milcewicz-Mika, I; Moreau, F; Morozov, A; Morris, J V; Mozer, M U; Mudrinic, M; Muller, K; Murin, P; Naumann, Th; Newman, P R; Niebuhr, C; Nikiforov, A; Nikitin, D; Nowak, G; Nowak, K; Olsson, J E; Osman, S; Ozerov, D; Palichik, V; Panagoulias, I; Pandurovic, M; Papadopoulou, Th; Pascaud, C; Patel, G D; Pejchal, O; Perez, E; Petrukhin, A; Picuric, I; Piec, S; Pitzl, D; Placakyte, R; Pokorny, B; Polifka, R; Povh, B; Radescu, V; Rahmat, A J; Raicevic, N; Raspiareza, A; Ravdandorj, T; Reimer, P; Rizvi, E; Robmann, P; Roland, B; Roosen, R; Rostovtsev, A; Rotaru, M; Tabasco, J E Ruiz; Rusakov, S; Salek, D; Sankey, D P C; Sauter, M; Sauvan, E; Schmitt, S; Schoeffel, L; Schoning, A; Schultz-Coulon, H C; Sefkow, F; Shaw-West, R N; Shtarkov, L N; Shushkevich, S; Sloan, T; Smiljanic, Ivan; Soloviev, Y; Sopicki, P; South, D; Spaskov, V; Specka, A; Staykova, Z; Steder, M; Stella, B; Stoicea, G; Straumann, U; Sunar, D; Sykora, T; Tchoulakov, V; Thompson, G; Thompson, P D; Toll, T; Tomasz, F; Tran, T H; Traynor, D; Trinh, T N; Truol, P; Tsakov, I; Tseepeldorj, B; Turnau, J; Urban, K; Valkarova, A; Vallee, C; Van Mechelen, P; Trevino, A Vargas; Vazdik, Y; Vinokurova, S; Volchinski, V; von den Driesch, M; Wegener, D; Wissing, Ch; Wunsch, E; Zacek, J; Zalesak, J; Zhang, Z; Zhokin, A; Zimmermann, T; Zohrabyan, H; Zomer, F

2010-01-01T23:59:59.000Z

442

Radio and gamma-ray connection in relativistic jets  

E-Print Network [OSTI]

Relativistic jets are one of the most powerful manifestations of the release of energy related to the supermassive black holes at the centre of active galactic nuclei (AGN). Their emission is observed across the entire electromagnetic spectrum, from the radio band to gamma rays. Despite decades of efforts, many aspects of the physics of relativistic jets remain elusive. In particular, the location and the mechanisms responsible for the high-energy emission and the connection of the variability at different wavelengths are among the greatest challenges in the study of AGN. Recent high resolution radio observations of flaring objects locate the high-energy emitting region downstream the jet at parsec scale distance from the central engine, posing questions on the nature of the seed photons upscattered to gamma-rays. Furthermore, monitoring campaigns of the most active blazars indicate that not all the high energy flares have the same characteristics in the various energy bands, even from the same source, making...

Orienti, M

2015-01-01T23:59:59.000Z

443

The Physics of Gamma-Ray Bursts and Relativistic Jets  

E-Print Network [OSTI]

We provide a comprehensive review of major developments in our understanding of gamma-ray bursts, with particular focus on the discoveries made within the last fifteen years when their true nature was uncovered. We describe the observational properties of photons from the radio to multi-GeV bands, both in the prompt emission and the afterglow phases. Mechanisms for the generation of these photons in GRBs are discussed and confronted with observations to shed light on the physical properties of these explosions, their progenitor stars and the surrounding medium. After presenting observational evidence that a powerful, collimated, jet moving at close to the speed of light is produced in these explosions, we describe our current understanding regarding the generation, acceleration, and dissipation of the jet and compare these properties with jets associated with AGNs and pulsars. We discuss mounting observational evidence that long duration GRBs are produced when massive stars die, and that at least some short d...

Kumar, Pawan

2014-01-01T23:59:59.000Z

444

Integrated coke, asphalt and jet fuel production process and apparatus  

DOE Patents [OSTI]

A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale and tar sands.

Shang, Jer Y. (McLean, VA)

1991-01-01T23:59:59.000Z

445

Medium induced jet absorption at relativistic heavy ion collisions  

E-Print Network [OSTI]

The dense medium created in Au + Au collisions at the Relativistic Heavy-Ion Collider (RHIC) significantly suppresses particle production from hard scattering processes and their characteristic back-to-back angular correlation. We present a simple model of jet absorption in dense matter which incorporates a realistic nuclear geometry. Our calculations are performed at the jet level and assume independent jet fragmentation in the vacuum. This model describes quantitatively the centrality dependence of the observed suppression of the high $p_T$ hadron yield and of the back-to-back angular correlations. The azimuthal anisotropy of high $p_T$ particle production can not be accounted for using a realistic nuclear geometry.

Axel Drees; Haidong Feng; Jiangyong Jia

2005-05-31T23:59:59.000Z

446

Decontamination performance of selected in situ technologies for jet fuel contamination. Master's thesis  

SciTech Connect (OSTI)

Specific study of jet fuel is warranted because of the quantitive and qualitative component differences between jet fuel and other hydrocarbon fuels. Quantitatively, jet fuel contains a larger aliphatic or saturate fraction and a smaller aromatic fraction than other fuels (i.e. heating oil and diesel oil) in the medium-boiling-point-distillate class of fuels. Since the aliphatic and aromatic fractions of fuel are not equally susceptible to biodegradation, jet fuel decontamination using biodegradation may be different from other fuels.

Chesley, G.D.

1993-01-01T23:59:59.000Z

447

Studies of forward jets and production of W, Z bosons at LHC energies  

E-Print Network [OSTI]

We report on application of QCD in calculations of forward jet and W, Z boson production cross sections at the Large Hadron Collider. In particular in case of jet production we emphasize dynamical features of the matrix elements controlling the resummation of logarithmically enhanced corrections in $\\sqrt{s}/E_T$, where $E_T$ is the jet production transverse energy. In case of production of W, Z bosons we focus on angular correlations between produced boson and hardest associated jet.

K. Kutak

2009-11-08T23:59:59.000Z

448

PUBLISHED VERSION Characterization of local heat fluxes around ICRF antennas on JET  

E-Print Network [OSTI]

) to characterize the heat fluxes on the protection of the JET ICRF antennas, using Infra-Red (IR) thermography

449

Method and apparatus for removing heat from electronic devices using synthetic jets  

DOE Patents [OSTI]

An apparatus for removing heat comprises a heat sink having a cavity, and a synthetic jet stack comprising at least one synthetic jet mounted within the cavity. At least one rod and at least one engaging structure to provide a rigid positioning of the at least one synthetic jet with respect to the at least one rod. The synthetic jet comprises at least one orifice through which a fluid is ejected.

Sharma, Rajdeep; Weaver, Jr., Stanton Earl; Seeley, Charles Erklin; Arik, Mehmet; Icoz, Tunc; Wolfe, Jr., Charles Franklin; Utturkar, Yogen Vishwas

2014-04-15T23:59:59.000Z

450

Gas Jet Disruption Mitigation Studies on Alcator C-Mod and DIII-D  

E-Print Network [OSTI]

Gas Jet Disruption Mitigation Studies on Alcator C-Mod and DIII-D R.S. Granetz1, E.M. Hollmann2, D-pressure noble gas jet High-pressure noble gas jets can mitigate 3 problems arising from disruptions, without molybdenum Be, W, C #12;Specific goals of these DIII-D and C-Mod gas jet experiments · Determine penetration

451

Single-Phase Self-Oscillating Jets for Enhanced Heat Transfer: Preprint  

SciTech Connect (OSTI)

Self-oscillating jets have potential to cool insulated gate bipolar transistors in vehicle power electronics modules.

Narumanchi, S.; Kelly, K.; Mihalic, M.; Gopalan, S.; Hester, R.; Vlahinos, A.

2008-06-01T23:59:59.000Z

452

Sensitivity of Pion versus Parton-Jet Nuclear Modification Factors to the Path-Length Dependence of Jet-Energy Loss at RHIC and LHC  

E-Print Network [OSTI]

We compare the jet-path length and beam-energy dependence of the pion nuclear modification factor and a parton-jet nuclear modification factor at RHIC and LHC. We contrast predictions based on a linear pQCD and a highly non-linear hybrid-AdS holographic model of jet-energy loss. We find that both models require a reduction of the jet-medium coupling from RHIC to LHC to account for the measured pion nuclear modification factor. In case of the parton-jet nuclear modification factor, however, which serves as a lower bound for the LO jet nuclear modification factor of reconstructed jets, the extracted data can be characterized without a reduced jet-medium coupling at LHC energies. We conclude that while reconstructed jets are sensitive to both quarks and gluons and thus provide more information than the pion nuclear modification factor, their information regarding the jet-medium coupling is limited due to the superimposition with NLO and medium effects. Hence, a detailed description of the underlying physics requ...

Betz, Barbara

2015-01-01T23:59:59.000Z

453

Azimuthal decorrelations and multiple parton interactions in photon+2 jet and photon+3 jet events in ppbar collisions at sqrt{s}=1.96 TeV  

SciTech Connect (OSTI)

Samples of inclusive {gamma} + 2 jet and {gamma} + 3 jet events collected by the D0 experiment with an integrated luminosity of about 1 fb{sup -1} in p{bar p} collisions at {radical}s = 1.96 TeV are used to measure cross sections as a function of the angle in the plane transverse to the beam direction between the transverse momentum (p{sub T}) of the {gamma} + leading jet system (jets are ordered in p{sub T}) and p{sub T} of the other jet for {gamma} + 2 jet, or p{sub T} sum of the two other jets for {gamma} + 3 jet events. The results are compared to different models of multiple parton interactions (MPI) in the pythia and sherpa Monte Carlo (MC) generators. The data indicate a contribution from events with double parton (DP) interactions and are well described by predictions provided by the pythia MPI models with p{sub T}-ordered showers and by sherpa with the default MPI model. The {gamma} + 2 jet data are also used to determine the fraction of events with DP interactions as a function of the azimuthal angle and as a function of the second jet p{sub T}.

Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls; Alverson, George O.; /Northeastern U.; Alves, Gilvan Augusto; /Rio de Janeiro, CBPF; Ancu, Lucian Stefan; /Nijmegen U. /Serpukhov, IHEP

2011-01-01T23:59:59.000Z

454

Jet conversions in a quark-gluon plasma  

E-Print Network [OSTI]

RAPID COMMUNICATIONS PHYSICAL REVIEW C 75, 051901(R) (2007) Jet conversions in a quark-gluon plasma W. Liu, C. M. Ko, and B. W. Zhang* Cyclotron Institute and Physics Department, Texas A&M University, College Station, Texas 77843-3366, USA... COMMUNICATIONS W. LIU, C. M. KO, AND B. W. ZHANG PHYSICAL REVIEW C 75, 051901(R) (2007) FIG. 1. (Color online) Collisional widths for gluon-to-quark (upper panels) and quark-to-gluon (lower panels) jet conversions in QGP due to elastic scattering q(q?)g? gq...

Liu, W.; Ko, Che Ming; Zhang, B. W.

2007-01-01T23:59:59.000Z

455

Measurement of multi-jet cross sections at ATLAS  

E-Print Network [OSTI]

Inclusive multi-jet production is studied using the ATLAS detector for proton-proton collisions with a center-of-mass energy of 7 TeV. The data sample corresponds to an integrated luminosity of 2.43 pb^-1, using the first proton-proton data collected by the ATLAS detector in 2010. Results on multi-jet cross sections are presented and compared to both leading-order plus parton-shower Monte Carlo predictions and next-to-leading-order QCD calculations.

Matthew Tamsett on behalf of the ATLAS collaboration

2011-09-30T23:59:59.000Z

456

Dynamics of quasi-two-dimensional turbulent jets  

E-Print Network [OSTI]

In turbulent jets, fluid is driven by momentum from an orifice into an environ- ment filled with similar fluid. The complexity of this flow, which has been studied for more than 80 years (see e.g. List, 1982, for a detailed review), resides in its turbulent... in time with an accuracy of approximately 1 %. We conducted two distinct sets of experiments using two qualitatively different techniques: dye tracking and particle image velocimetry (PIV). 7 2 Meandering and self-similarity of quasi-two-dimensional jets x...

Landel, Julien Rémy Dominique Gérard

2012-11-13T23:59:59.000Z

457

Measurement of the Top Pair Production Cross Section in the Lepton + Jets Channel Using a Jet Flavor Discriminant  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We present a new method to measure the top quark pair production cross section and the background rates with data corresponding to an integrated luminosity of 2.7 fb-1 from p p? collisions at ?s = 1.96 TeV collected with the CDF II Detector. We select events with a single electron or muon candidate, missing transverse energy, and at least one b-tagged jet. We perform a simultaneous fit to a jet flavor discriminant across nine samples defined by the number of jets and b-tags. An advantage of this approach is that many systematic uncertainties are measured in situ and inversely scale with integrated luminosity. We measure a top cross section of ?tt? = 7.64 ± 0.57 (stat + syst) ± 0.45 (luminosity) pb.

Aaltonen, T.; Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Apresyan, A.

2011-08-01T23:59:59.000Z

458

Deep convection in the Irminger Sea forced by the Greenland tip jet  

E-Print Network [OSTI]

Deep convection in the Irminger Sea forced by the Greenland tip jet Robert S. Pickart*, Michael A atmospheric jet known as the Greenland tip jet, which forms periodically in the lee of Cape Farewell, Greenland, and is associated with elevated heat flux and strong wind stress curl. Using a history of tip

Pickart, Robert S.

459

Annual Report of the EURATOM/CCFE Fusion Programme 2009/10 3 JET Operations  

E-Print Network [OSTI]

of experimental programme operations, on 24 October. The EP2 shutdown activity managed and conducted by CCFE Operations 3.2 OPERATIONS OVERVIEW JET commissioning and operation is conducted in a shift pattern, with twoAnnual Report of the EURATOM/CCFE Fusion Programme 2009/10 3.1 3 JET Operations 3 JET Operations 3

460

Jet Measurements and Extraction of the Strong Coupling Constant at HERA  

E-Print Network [OSTI]

Results on jet measurements in neutral current deep inelastic scattering at HERA are presented. The low-$x_{Bj}$ and low-$Q^2$ region is explicitly investigated using forward jet production and the azimuthal asymmetry between jets in dijet production. Recent results on the determination of the strong coupling constant, $\\alpha_s(M_Z)$, are discussed.

A. A. Savin

2005-05-22T23:59:59.000Z

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Introduction Idealized Moist Jet/Front Waves Ray Tracing Momentum Flux/Forcing Conclusion Gravity Waves  

E-Print Network [OSTI]

Introduction Idealized Moist Jet/Front Waves Ray Tracing Momentum Flux/Forcing Conclusion Gravity Waves in Moist Baroclinic Jet-Front Systems Junhong Wei, Fuqing Zhang Department of Meteorology The Pennsylvania State University Tuesday 19th August, 2014 #12;Introduction Idealized Moist Jet/Front Waves Ray

Thompson, Anne

462

Measurements on 5:1 Scale Abrasive Water Jet Cutting Head Models  

E-Print Network [OSTI]

nozzle orifice s Isentropic (e.g. in w.jet.s) w.jet Water jet water Water Superscripts: * Symbol for non, an achievable accuracy also mentioned by Hashish in [7]. Improving the AWJ cutting process in a way that parts with precise accuracy of motion, a precisely manufactured tool (cutting head) and optimally set machining

463

Observations of rotating jets of carbon monoxide in comet Hale-Bopp with the IRAM interferometer  

E-Print Network [OSTI]

Observations of rotating jets of carbon monoxide in comet Hale-Bopp with the IRAM interferometer the projection of the jet mean velocity on the line of sight. As the jet rotates with the nucleus, the velocity, an interesting feature is to be noted. We have computed the mean photometric centre from the peak intensity

Demoulin, Pascal

464

ComputerScience,TexasA&MUniversity JetMax: Scalable Max-Min  

E-Print Network [OSTI]

1 ComputerScience,TexasA&MUniversity JetMax: Scalable Max-Min Congestion Control for High- Speed Heterogeneous Networks JetMax: Scalable MaxJetMax: Scalable Max--MinMin Congestion Control for High congestion control and its designed properties · Analysis of existing max-min methods XCP, MKC, and MKC

Loguinov, Dmitri

465

Development of Liquid-Vapor Core Reactors with MHD Generator for Space Power and Propulsion Applications  

SciTech Connect (OSTI)

Any reactor that utilizes fuel consisting of a fissile material in a gaseous state may be referred to as a gaseous core reactor (GCR). Studies on GCRs have primarily been limited to the conceptual phase, mostly due to budget cuts and program cancellations in the early 1970's. A few scientific experiments have been conducted on candidate concepts, primarily of static pressure fissile gas filling a cylindrical or spherical cavity surrounded by a moderating shell, such as beryllium, heavy water, or graphite. The main interest in this area of nuclear power generation is for space applications. The interest in space applications has developed due to the promise of significant enhancement in fuel utilization, safety, plant efficiency, special high-performance features, load-following capabilities, power conversion optimization, and other key aspects of nuclear power generation. The design of a successful GCR adapted for use in space is complicated. The fissile material studied in the pa st has been in a fluorine compound, either a tetrafluoride or a hexafluoride. Both of these molecules have an impact on the structural material used in the making of a GCR. Uranium hexafluoride as a fuel allows for a lower operating temperature, but at temperatures greater than 900K becomes essentially impossible to contain. This difficulty with the use of UF6 has caused engineers and scientists to use uranium tetrafluoride, which is a more stable molecule but has the disadvantage of requiring significantly higher operating temperatures. Gas core reactors have traditionally been studied in a steady state configuration. In this manner a fissile gas and working fluid are introduced into the core, called a cavity, that is surrounded by a reflector constructed of materials such as Be or BeO. These reactors have often been described as cavity reactors because the density of the fissile gas is low and criticality is achieved only by means of the reflector to reduce neutron leakage from the core. Still there are problems of containment since many of the proposed vessel materials such as W or Mo have high neutron cross sections making the design of a critical system difficult. There is also the possibility for a GCR to remain in a subcritical state, and by the use of a shockwave mechanism, increase the pressure and temperature inside the core to achieve criticality. This type of GCR is referred to as a shockwave-driven pulsed gas core reactor. These two basic designs were evaluated as advance concepts for space power and propulsion.

Samim Anghaie

2002-08-13T23:59:59.000Z

466

RADIOISOTOPE-DRIVEN DUAL-MODE PROPULSION SYSTEM FOR CUBESAT-SCALE PAYLOADS TO THE OUTER PLANETS  

SciTech Connect (OSTI)

It is apparent the cost of planetary exploration is rising as mission budgets declining. Currently small scientific beds geared to performing limited tasks are being developed and launched into low earth orbit (LEO) in the form of small-scale satellite units, i.e., CubeSats. These micro- and nano-satellites are gaining popularity among the university and science communities due to their relatively low cost and design flexibility. To date these small units have been limited to performing tasks in LEO utilizing solar-based power. If a reasonable propulsion system could be developed, these CubeSat platforms could perform exploration of various extra-terrestrial bodies within the solar system engaging a broader range of researchers. Additionally, being mindful of mass, smaller cheaper launch vehicles (approximately 1,000 kgs to LEO) can be targeted. Thus, in effect, allows for beneficial exploration to be conducted within limited budgets. Researchers at the Center for Space Nuclear Research (CSNR) are proposing a low mass, radioisotope-based, dual-mode propulsion system capable of extending the exploration realm of these CubeSats out of LEO.

N. D. Jerred; T. M. Howe; S. D. Howe; A. Rajguru

2014-02-01T23:59:59.000Z

467

Heavy vehicle propulsion system materials program semi-annual progress report for October 1997 through March 1998  

SciTech Connect (OSTI)

The purpose of the Heavy Vehicle Propulsion System materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1--3 trucks to realize a 35{percent} fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7--8 trucks. The Office of Transportation Technologies, Office of Heavy Vehicle Technologies (OTT OHVT) has an active program to develop the technology for advanced LE-55 diesel engines with 55{percent} efficiency and low emissions levels of 2.0 g/bhp-h NO{sub x} and 0.05 g/bhp-h particulates. The goal is also for the LE-55 engine to run on natural gas with efficiency approaching that of diesel fuel. The LE-55 program is being completed in FY 1997 and, after approximately 10 years of effort, has largely met the program goals of 55{percent} efficiency and low emissions. However, the commercialization of the LE-55 technology requires more durable materials than those that have been used to demonstrate the goals. Heavy Vehicle Propulsion System Materials will, in concert with the heavy-duty diesel engine companies, develop the durable materials required to commercialize the LE-55 technologies.

Johnson, D.R.

1998-06-01T23:59:59.000Z

468

LOFT as a discovery machine for jetted Tidal Disruption Events  

E-Print Network [OSTI]

This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of jetted tidal disruption events. For a summary, we refer to the paper.

Rossi, E M; Fender, R; Jonker, P; Komossa, S; Paragi, Z; Prandoni, I; Zampieri, L

2015-01-01T23:59:59.000Z

469

SKA as a powerful hunter of jetted Tidal Disruption Events  

E-Print Network [OSTI]

Observational consequences of the tidal disruption of stars by supermassive black holes (SMBHs) can enable us to discover quiescent SMBHs and constrain their mass function. Moreover, observing jetted TDEs (from previously non-active galaxies) provides us with a new means of studying the early phases of jet formation and evolution in an otherwise "pristine" environment. Although several (tens) TDEs have been discovered since 1999, only two jetted TDEs have been recently discovered in hard X-rays, and only one, Swift J1644+57, has a precise localization which further supports the TDE interpretation. These events alone are not sufficient to address those science issues, which require a substantial increase of the current sample. Despite the way they were discovered, the highest discovery potential for {\\em jetted} TDEs is not held by current and up-coming X-ray instruments, which will yield only a few to a few tens events per year. In fact, the best strategy is to use the Square Kilometer Array to detect TDEs an...

Donnarumma, I; Fender, R; Komossa, S; Paragi, Z; Van Velzen, S; Prandoni, I

2015-01-01T23:59:59.000Z

470

CERN Hg Jet System V.B. Graves  

E-Print Network [OSTI]

Collaboration Mtg 16 Feb 05 Alternative Hg Delivery System Hydraulic Fluid Cylinder (3000 psi) Hg Cylinder (1000 energy performed on piston = press*area*dist/time 11 Hyd Pump pump inefficiency 8 11 340 340 6 8 Piston Sized for 20sec jet Drain Hg Supply Hg Return Position Sensor Hydraulic Lines Hg Cylinder Vent Line #12

McDonald, Kirk

471

Jet photoproduction and the structure of the photon  

E-Print Network [OSTI]

Various jet observables in photoproduction are studied and compared to data from HERA. The feasibility of using a dijet sample for constraining the parton distributions in the photon is then studied. For the current data the experimental and theoretical uncertainties are comparable to the variation due to changing the photon parton distribution set.

B. W. Harris; J. F. Owens

1997-12-08T23:59:59.000Z

472

Diagnostic of fusion neutrons on JET tokamak using diamond detector  

SciTech Connect (OSTI)

In 2011-2012, an experimental campaign with a significant yield of fusion neutrons was carried out on the JET tokamak. During this campaign the facility was equipped with two diamond detectors based on natural and artificial CVD diamond. These detectors were designed and manufactured in State Research Center of Russian Federation TRINITI. The detectors measure the flux of fast neutrons with energies above 0.2 MeV. They have been installed in the torus hall and the distance from the center of plasma was about 3 m. For some of the JET pulses in this experiment, the neutron flux density corresponded to the operational conditions in collimator channels of ITER Vertical Neutron Camera. The main objective of diamond monitors was the measurement of total fast neutron flux at the detector location and the estimation of the JET total neutron yield. The detectors operate as threshold counters. Additionally a spectrometric measurement channel has been configured that allowed us to distinguish various energy components of the neutron spectrum. In this paper we describe the neutron signal measuring and calibration procedure of the diamond detector. Fluxes of DD and DT neutrons at the detector location were measured. It is shown that the signals of total neutron yield measured by the diamond detector correlate with signals measured by the main JET neutron diagnostic based on fission chambers with high accuracy. This experiment can be considered as a successful test of diamond detectors in ITER-like conditions.

Nemtsev, G.; Amosov, V.; Marchenko, N.; Meshchaninov, S.; Rodionov, R. [Institution Project center ITER, Moscow (Russian Federation); Popovichev, S. [EURATOM-CCFE Fusion Association, Culham Science Centre, Abingdon, OXON, OX14 3DB (United Kingdom); Collaboration: JET EFDA Conbributors

2014-08-21T23:59:59.000Z

473

Relativistic Jets Shine through Shocks or Magnetic Reconnection?  

E-Print Network [OSTI]

Observations of gamma-ray-bursts and jets from active galactic nuclei reveal that the jet flow is characterized by a high radiative efficiency and that the dissipative mechanism must be a powerful accelerator of non-thermal particles. Shocks and magnetic reconnection have long been considered as possible candidates for powering the jet emission. Recent progress via fully-kinetic particle-in-cell simulations allows us to revisit this issue on firm physical grounds. We show that shock models are unlikely to account for the jet emission. In fact, when shocks are efficient at dissipating energy, they typically do not accelerate particles far beyond the thermal energy, and vice versa. In contrast, we show that magnetic reconnection can deposit more than 50% of the dissipated energy into non-thermal leptons as long as the energy density of the magnetic field in the bulk flow is larger than the rest mass energy density. The emitting region, i.e., the reconnection downstream, is characterized by a rough energy equipa...

Sironi, Lorenzo; Giannios, Dimitrios

2015-01-01T23:59:59.000Z

474

Outflows and Jets from Collapsing Magnetized Cloud Cores  

E-Print Network [OSTI]

Star formation is usually accompanied by outflow phenomena. There is strong evidence that these outflows and jets are launched from the protostellar disk by magneto-rotational processes. Here, we report on our three dimensional, adaptive mesh, magneto-hydrodynamic simulations of collapsing, rotating, magnetized Bonnor-Ebert-Spheres whose properties are taken directly from observations. In contrast to the pure hydro case where no outflows are seen, our present simulations show an outflow from the protodisk surface at ~ AU and a jet at ~ 0.07 AU after a strong toroidal magnetic field build up. The large scale outflow, which extends up to ~ AU at the end of our simulation, is driven by toroidal magnetic pressure (spring), whereas the jet is powered by magneto-centrifugal force (fling). At the final stage of our simulation these winds are still confined within two respective shock fronts. Furthermore, we find that the jet-wind and the disk-anchored magnetic field extracts a considerable amount of angular momentum from the protostellar disk. The initial spin of our cloud core was chosen high enough to produce a binary system. We indeed find a close binary system (separation ~ 3 R_sol) which results from the fragmentation of an earlier formed ring structure. The magnetic field strength in these protostars reaches ~ 3 kG and becomes about 3 G at 1 AU from the center in agreement with recent observational results.

Robi Banerjee; Ralph E. Pudritz

2005-12-13T23:59:59.000Z

475

EXPERIMENTAL ANALYSIS OF JET FIRE IMPINGEMENT ON INDUSTRIAL PIPE  

E-Print Network [OSTI]

EXPERIMENTAL ANALYSIS OF JET FIRE IMPINGEMENT ON INDUSTRIAL PIPE Patei S.*, Durasse! T. INERIS fîres and pool fïres can increase hazards when they impinge and engulf on pipes or vessels. Then, thèse of fïres on industrial pipes and tanks. Its main objective is to develop, to validate and to produce one

Paris-Sud XI, Université de

476

SCALED EXPERIMENTS EVALUATING PULSE JET MIXING OF SLURRIES  

SciTech Connect (OSTI)

Pulse jet mixing (PJM) tests with noncohesive solids in Newtonian liquid were conducted at three geometric scales to support the design of mixing systems for the Hanford Waste Treatment and Immobilization Plant. The test data will be used to develop mixing models. The models predict the cloud height (the height to which solids will be lifted by the PJM action) and the critical suspension velocity (the minimum velocity needed to ensure all solids have been lifted from the floor. From the cloud height estimate, the concentration of solids near the vessel floor and the minimum velocity predicted to lift solids can be calculated. The test objective was to observe the influence of vertically downward-directed jets on noncohesive solids in a series of scaled tanks with several bottom shapes. The test tanks and bottom shapes included small-and large-scale tanks with elliptical bottoms, a mid-scale tank with a spherical bottom, and a large-scale tank with an F&D bottom. During testing, the downward-directed jets were operated in either a steady flow condition or a pulsed (periodic) flow condition. The mobilization of the solids resulting from the jets was evaluated based on: the motion/agitation of the particulate on the tank floor and the elevation the solids reach within the tank; the height the solids material reaches in the tank is referred to as the cloud height (HC).

Bamberger, Judith A.; Meyer, Perry A.; Enderlin, Carl W.; Fort, James A.; Wells, Beric E.; Minette, Michael J.; Burns, Carolyn A.; Baer, Ellen BK; Eakin, David E.; Elmore, Monte R.; Snyder, Sandra F.

2009-11-13T23:59:59.000Z

477

THE JET PULSE POWER SUPPLY SYSTEM J. B. HICKS  

E-Print Network [OSTI]

between the two major components of the power supply (flywheel-generator-convertors (FGC) and transformer between the two possible components of the power supply, i. e. flywheel. generator-convertors and transformer-controlled-convertors. The proposed JET power supply system is described, together with an outline

Paris-Sud XI, Université de

478

CFD optimization study of high-efficiency jet ejectors  

E-Print Network [OSTI]

?????????.. 12 Internal Flow Field??????????.??? 14 Shock Wave???????????????.. 15 Multi-Stage Jet Ejector System???????.? 18 III THEORY???????????????????.. 22... CASES?... 253 APPENDIX D SALT WATER PROPERTIES AND THE DETAIL DATA OF THE DESALINATION CASE STUDY??.. 258 APPENDIX E THE PROCEDURE TO CALCULATE THE INLET MOTIVE-STREAM PRESSURE?????????.. 266 APPENDIX F RESULT...

Watanawanavet, Somsak

2009-05-15T23:59:59.000Z

479

Breakup of diminutive Rayleigh jets Wim van Hoeve,1  

E-Print Network [OSTI]

, and viscosity J. Eggers and T. F. Dupont, J. Fluid Mech. 262, 205 1994 ; X. D. Shi, M. P. Brenner, and S. R to investigate the effect of jet velocity and liquid viscosity on the formation of satellite droplets distribu- tion through spray-drying results in a reduction of transpor- tation and energy costs. In inkjet

Snoeijer, Jacco

480

Numerical simulation of turbulent jet primary breakup in Diesel engines  

E-Print Network [OSTI]

Numerical simulation of turbulent jet primary breakup in Diesel engines Peng Zeng1 Marcus Herrmann" IRMA Strasbourg, 23.Jan.2008 #12;Introduction DNS of Primary Breakup in Diesel Injection Phase Transition Modeling Turbulence Modeling Summary Outline 1 Introduction 2 DNS of Primary Breakup in Diesel

Helluy, Philippe

Note: This page contains sample records for the topic "jordana jet propulsion" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Technique for estimating jet fuel prices from energy futures market  

SciTech Connect (OSTI)

This report presents a statistical analysis of future prices of petroleum products for use in predicting the monthly average retail price of kerosene-type jet fuel. The method of least squares was employed to examine the relationship between kerosene-type jet fuel retail prices and energy futures prices. Regression equations were constructed for four of the petroleum commodities traded on the energy futures market: heating oil No. 2, leaded regular gasoline, crude oil, and unleaded gasoline. Thirty-nine regression equations were estimated by the method of least squares to relate the cash price of kerosene-type jet fuel to the futures prices of the above four petroleum commodities for contract periods of 1 to 12 months. The analysis revealed that 19 of the 39 first-order linear regression equations provided a good fit to the data. Specifically, heating oil No. 2 performed better than the order energy futures in predicting the price of kerosene-type jet fuel. The only information required to use these regression equations are energy futures prices which are available daily from the Wall Street Journal. 5 refs., 4 tabs.

Vineyard, T.A.

1988-05-01T23:59:59.000Z

482

Gravity waves excited by jets: Propagation versus generation R. Plougonven  

E-Print Network [OSTI]

Gravity waves excited by jets: Propagation versus generation R. Plougonven School of Mathematics imposed by the generation mechanism. In proceeding so, effects due to the propagation of the waves through simulations demonstrate that the propagation of inertia-gravity waves through horizontal deformation

Plougonven, Riwal

483

AIAA 2004-6386 ZERO-MASS PULSATILE JETS FOR  

E-Print Network [OSTI]

AIAA 2004-6386 ZERO-MASS PULSATILE JETS FOR UNMANNED UNDERWATER VEHICLE MANEUVERING K. Mohseni speeds. Introduction Unmanned Underwater Vehicles (UUVs) will play a major role in the future/monitoring of underwa- ter structures, and underwater battlespace. Two main categories of unmanned underwater vehicles

Mohseni, Kamran

484

Measurement of the ratio of differential cross sections ?(pp-bar?Z+b?jet)/?(pp-bar?Z+jet) in pp-bar collisions at s?=1.96??TeV  

E-Print Network [OSTI]

We measure the ratio of cross sections, ?(pp-bar?Z+b?jet)/?(pp-bar?Z+jet), for associated production of a Z boson with at least one jet. The ratio is also measured as a function of the Z boson transverse momentum, jet ...

Baringer, Philip S.; Bean, Alice; Chen, G.; Clutter, Justace Randall; Sekaric, Jadranka; Wilson, Graham Wallace; Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Askew, A.; Atkins, S.; Augsten, K.

2013-05-28T23:59:59.000Z

485

Long Term Tritium Trapping in TFTR and JET  

SciTech Connect (OSTI)

Tritium retention in TFTR [Tokamak Fusion Test Reactor] and JET [Joint European Torus] shows striking similarities and contrasts. In TFTR, 5 g of tritium were injected into circular plasmas over a 3.5 year period, mostly by neutral-beam injection. In JET, 35 g were injected into divertor plasmas over a 6 month campaign, mostly by gas puffing. In TFTR, the bumper limiter provided a large source of eroded carbon and a major part of tritium was co-deposited on the limiter and vessel wall. Only a small area of the co-deposit flaked off. In JET, the wall is a net erosion area, and co-deposition occurs principally in shadowed parts of the inner divertor, with heavy flaking. In both machines, the initial tritium retention, after a change from deuterium [D] to tritium [T] gas puffing, is high and is due to isotope exchange with deuterium on plasma-facing surfaces (dynamic inventory). The contribution of co-deposition is lower but cumulative, and is revealed by including periods of D fueling that reversed the T/D isotope exchange. Ion beam analysis of flakes from TFTR showed an atomic D/C ratio of 0.13 on the plasma facing surface, 0.25 on the back surface and 0.11 in the bulk. Data from a JET divertor tile showed a larger D/C ratio with 46% C, 30% D, 20% H and 4% O. Deuterium, tritium, and beryllium profiles have been measured and show a thin less than 50 micron co-deposited layer. Flakes retrieved from the JET vacuum vessel exhibited a high tritium release rate of 2e10 Bq/month/g. BBQ modeling of the effect of lithium on retention in TFTR showed overlapping lithium and tritium implantation and a 1.3x increase in local T retention.

C.H. Skinner; C.A. Gentile; K.M. Young; J.P. Coad; J.T. Hogan; R.-D. Penzhorn; and N. Bekris

2001-07-24T23:59:59.000Z

486

Production of $K^{0}_{S}$ and $\\Lambda$ in Quark and Gluon Jets from $Z^{0}$ Decay  

E-Print Network [OSTI]

The production of K^0_S mesons and Lambda baryons in quark and gluon jets has been investigated using two complementary techniques. In the first approach, which provides high statistical accuracy, jets were selected using different jet finding algorithms and ordered according to their energy. Production rates were determined taking into account the dependences of quark and gluon compositions as a function of jet energy as predicted by Monte Carlo models. Selecting three-jet events with the k_perp (Durham) jet finder (y_cut = 0.005), the ratios of K^0_S and Lambda production rates in gluon and quark jets relative to the mean charged particle multiplicity were found to be 1.10 +/- 0.02 +/- 0.02 and 1.41 +/- 0.04 +/- 0.04, respectively, where the first uncertainty is statistical and the second is systematic. In the second approach, a new method of identifying quark jets based on the collimation of energy flow around the jet axis is introduced and was used to anti-tag gluon jets in symmetric (Y-shaped) three-jet ...

Ackerstaff, K; Allison, J; Altekamp, N; Anderson, K J; Anderson, S; Arcelli, S; Asai, S; Ashby, S F; Axen, D A; Azuelos, Georges; Ball, A H; Barberio, E; Barlow, R J; Bartoldus, R; Batley, J Richard; Baumann, S; Bechtluft, J; Behnke, T; Bell, K W; Bella, G; Bentvelsen, Stanislaus Cornelius Maria; Bethke, Siegfried; Betts, S; Biebel, O; Biguzzi, A; Bird, S D; Blobel, Volker; Bloodworth, Ian J; Bobinski, M; Bock, P; Böhme, J; Boutemeur, M; Braibant, S; Bright-Thomas, P G; Brown, R M; Burckhart, Helfried J; Burgard, C; Bürgin, R; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Chrisman, D; Ciocca, C; Clarke, P E L; Clay, E; Cohen, I; Conboy, J E; Cooke, O C; Couyoumtzelis, C; Coxe, R L; Cuffiani, M; Dado, S; Dallavalle, G M; Davis, R; De Jong, S; del Pozo, L A; de Roeck, A; Desch, Klaus; Dienes, B; Dixit, M S; Doucet, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Eatough, D; Estabrooks, P G; Evans, H G; Fabbri, Franco Luigi; Fanfani, A; Fanti, M; Faust, A A; Fiedler, F; Fierro, M; Fischer, H M; Fleck, I; Folman, R; Fürtjes, A; Futyan, D I; Gagnon, P; Gary, J W; Gascon, J; Gascon-Shotkin, S M; Geich-Gimbel, C; Geralis, T; Giacomelli, G; Giacomelli, P; Gibson, V; Gibson, W R; Gingrich, D M; Glenzinski, D A; Goldberg, J; Gorn, W; Grandi, C; Gross, E; Grunhaus, Jacob; Gruwé, M; Hanson, G G; Hansroul, M; Hapke, M; Hargrove, C K; Hartmann, C; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, Richard J; Herndon, M; Herten, G; Heuer, R D; Hildreth, M D; Hill, J C; Hillier, S J; Hobson, P R; Höcker, Andreas; Homer, R James; Honma, A K; Horváth, D; Hossain, K R; Howard, R; Hüntemeyer, P; Igo-Kemenes, P; Imrie, D C; Ishii, K; Jacob, F R; Jawahery, A; Jeremie, H; Jimack, Martin Paul; Joly, A; Jones, C R; Jovanovic, P; Junk, T R; Karlen, D A; Kartvelishvili, V G; Kawagoe, K; Kawamoto, T; Kayal, P I; Keeler, Richard K; Kellogg, R G; Kennedy, B W; Klier, A; Kluth, S; Kobayashi, T; Kobel, M; Koetke, D S; Kokott, T P; Kolrep, M; Komamiya, S; Kowalewski, R V; Kress, T; Krieger, P; Von Krogh, J; Kyberd, P; Lafferty, G D; Lanske, D; Lauber, J; Lautenschlager, S R; Lawson, I; Layter, J G; Lazic, D; Lee, A M; Lefebvre, E; Lellouch, Daniel; Letts, J; Levinson, L; Liebisch, R; List, B; Littlewood, C; Lloyd, A W; Lloyd, S L; Loebinger, F K; Long, G D; Losty, Michael J; Ludwig, J; Liu, D; Macchiolo, A; MacPherson, A L; Mannelli, M; Marcellini, S; Markopoulos, C; Martin, A J; Martin, J P; Martínez, G; Mashimo, T; Mättig, P; McDonald, W J; McKenna, J A; McKigney, E A; McMahon, T J; McPherson, R A; Meijers, F; Menke, S; Merritt, F S; Mes, H; Meyer, J; Michelini, Aldo; Mihara, S; Mikenberg, G; Miller, D J; Mir, R; Mohr, W; Montanari, A; Mori, T; Nagai, K; Nakamura, I; Neal, H A; Nellen, B; Nisius, R; O'Neale, S W; Oakham, F G; Odorici, F; Ögren, H O; Oreglia, M J; Orito, S; Pálinkás, J; Pásztor, G; Pater, J R; Patrick, G N; Patt, J; Pérez-Ochoa, R; Petzold, S; Pfeifenschneider, P; Pilcher, J E; Pinfold, James L; Plane, D E; Poffenberger, P R; Poli, B; Polok, J; Przybycien, M B; Rembser, C; Rick, Hartmut; Robertson, S; Robins, S A; Rodning, N L; Roney, J M; Roscoe, K; Rossi, A M; Rozen, Y; Runge, K; Runólfsson, O; Rust, D R; Sachs, K; Saeki, T; Sahr, O; Sang, W M; Sarkisyan-Grinbaum, E; Sbarra, C; Schaile, A D; Schaile, O; Scharf, F; Scharff-Hansen, P; Schieck, J; Schmitt, B; Schmitt, S; Schöning, A; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Schwick, C; Scott, W G; Seuster, R; Shears, T G; Shen, B C; Shepherd-Themistocleous, C H; Sherwood, P; Siroli, G P; Sittler, A; Skuja, A; Smith, A M; Snow, G A; Sobie, Randall J; Söldner-Rembold, S; Sproston, M; Stahl, A; Stephens, K; Steuerer, J; Stoll, K; Strom, D; Ströhmer, R; Tafirout, R; Talbot, S D; Tanaka, S; Taras, P; Tarem, S; Teuscher, R; Thiergen, M; Thomson, M A; Von Törne, E; Torrence, E; Towers, S; Trigger, I; Trócsányi, Z L; Tsur, E; Turcot, A S; Turner-Watson, M F; Van Kooten, R; Vannerem, P; Verzocchi, M; Vikas, P; Voss, H; Wäckerle, F; Wagner, A; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wermes, N; White, J S; Wilson, G W; Wilson, J A; Wyatt, T R; Yamashita, S; Yekutieli, G; Zacek, V; Zer-Zion, D

1999-01-01T23:59:59.000Z

487

Experimental measurements in a radio frequency discharge heated supersonic flow: Evaluation of a potential electric propulsion thruster  

SciTech Connect (OSTI)

An operational radio frequency discharge-driven supersonic flow system, which utilizes an inductively and capacitively coupled plasma (ICCP) tube to produce high enthalpy source gas, is described. The ICCP coupled to a properly designed nozzle represents a potential electric propulsion device. The high gas temperatures achieved in the plasma discharge (> 5000 K) and the electrodeless nature of the tube's operation offers potentially high thruster performance coupled and long operational lifetime. A preliminary characterization of the current system was established using emission and probe-based measurements. A nominal peak specific impulse of 155 s was estimated for operation with argon. The calculated thrust based upon the peak velocity and mass flow through the device is 1.1 N. 14 refs., 10 figs.

Wantuck, P.J.; Hull, D.E.

1991-01-01T23:59:59.000Z

488

Deuterium-Tritium Pulse Propulsion with Hydrogen as Propellant and the Entire Spacecraft as a Gigavolt Capacitor for Ignition  

E-Print Network [OSTI]

A deuterium-tritium (DT) nuclear pulse propulsion concept for fast interplanetary transport is proposed utilizing almost all the energy for thrust and without the need for a large radiator: 1. By letting the thermonuclear micro-explosion take place in the center of a liquid hydrogen sphere with the radius of the sphere large enough to slow down and absorb the neutrons of the DT fusion reaction, heating the hydrogen to a fully ionized plasma at a temperature of ~ 105 K. 2. By using the entire spacecraft as a magnetically insulated gigavolt capacitor, igniting the DT micro-explosion with an intense GeV ion beam discharging the gigavolt capacitor, possible if the space craft has the topology of a torus.

Winterberg, Friedwardt

2012-01-01T23:59:59.000Z

489

Deuterium-Tritium Pulse Propulsion with Hydrogen as Propellant and the Entire Spacecraft as a Gigavolt Capacitor for Ignition  

E-Print Network [OSTI]

A deuterium-tritium (DT) nuclear pulse propulsion concept for fast interplanetary transport is proposed utilizing almost all the energy for thrust and without the need for a large radiator: 1. By letting the thermonuclear micro-explosion take place in the center of a liquid hydrogen sphere with the radius of the sphere large enough to slow down and absorb the neutrons of the DT fusion reaction, heating the hydrogen to a fully ionized plasma at a temperature of ~ 105 K. 2. By using the entire spacecraft as a magnetically insulated gigavolt capacitor, igniting the DT micro-explosion with an intense GeV ion beam discharging the gigavolt capacitor, possible if the space craft has the topology of a torus.

Friedwardt Winterberg

2012-07-31T23:59:59.000Z

490

Universal parametrization of jet production based on parton and fragment rapidities  

E-Print Network [OSTI]

As the signature manifestation of QCD in high energy nuclear collisions jet production provides essential tests of that theory. But event-wise jet reconstruction can be complex and susceptible to measurement bias. And QCD theory in the form of Monte Carlo models of elementary collisions can also be complex and difficult to test. It may be beneficial to construct a simple static model of jet production in p-p collisions to facilitate data comparisons and model tests. QCD is a logarithmic theory featuring variations with energy scale of the form $\\log(s/s_0)$. Jet-related data such as parton fragmentation functions plotted on logarithmic rapidities exhibit self-similar scaling behavior which admits simple and accurate parametrization with only a few parameters. In this study we extend that method to construct a parametrization of jet (scattered parton) momentum spectra based on certain measured logarithmic jet production trends. The parametrization is established with Sp\\=pS jet data and then extrapolated for comparison with Tevatron and LHC jet data. In addition, the jet production model from the present study is combined with a parametrization of p-\\=p fragmentation functions to predict the minimum-bias jet fragment contribution to hadron $p_t$ spectra. The prediction is compared with published p-p spectrum data to test the self-consistency of the model.

Thomas A. Trainor

2014-03-14T23:59:59.000Z

491

Magnetic Untwisting in Solar Jets that Go into the Outer Corona in Polar Coronal Holes  

E-Print Network [OSTI]

We study 14 large solar jets observed in polar coronal holes. In EUV movies from SDO/AIA, each jet appears similar to most X-ray jets and EUV jets that erupt in coronal holes, but each is exceptional in that it goes higher than most, so high that it is observed in the outer corona beyond 2.2 RSun in images from the SOHO/LASCO/C2 coronagraph. From AIA He II 304 {\\AA} movies and LASCO/C2 running-difference images of these high-reaching jets, we find: (1) the front of the jet transits the corona below 2.2 RSun at a speed typically several times the sound speed; (2) each jet displays an exceptionally large amount of spin as it erupts; (3) in the outer corona, most of the jets display measureable swaying and bending of a few degrees in amplitude; in three jets the swaying is discernibly oscillatory with a period of order 1 hour. These characteristics suggest that the driver in these jets is a magnetic-untwisting wave that is basically a large-amplitude (i.e., non-linear) torsional Alfven wave that is put into the ...

Moore, Ronald L; Falconer, David A

2015-01-01T23:59:59.000Z

492

Kaon fragmentation function from NJL-jet model  

SciTech Connect (OSTI)

The NJL-jet model provides a sound framework for calculating the fragmentation functions in an effective chiral quark theory, where the momentum and isospin sum rules are satisfied without the introduction of ad hoc parameters [1]. Earlier studies of the pion fragmentation functions using the Nambu-Jona-Lasinio (NJL) model within this framework showed good qualitative agreement with the empirical parameterizations. Here we extend the NJL-jet model by including the strange quark. The corrections to the pion fragmentation function and corresponding kaon fragmentation functions are calculated using the elementary quark to quark-meson fragmentation functions from NJL. The results for the kaon fragmentation function exhibit a qualitative agreement with the empirical parameterizations, while the unfavored strange quark fragmentation to pions is shown to be of the same order of magnitude as the unfavored light quark's. The results of these studies are expected to provide important guidance for the analysis of a large variety of semi-inclusive data.

Matevosyan, Hrayr H.; Thomas, Anthony W. [CSSM, School of Chemistry and Physics, University of Adelaide, Adelaide SA 5005 (Australia); Bentz, Wolfgang [Department of Physics, School of Science, Tokai University, Hiratsuka-shi, Kanagawa 259-1292 (Japan)

2010-07-27T23:59:59.000Z

493

NJL-jet model for quark fragmentation functions  

SciTech Connect (OSTI)

A description of fragmentation functions which satisfy the momentum and isospin sum rules is presented in an effective quark theory. Concentrating on the pion fragmentation function, we first explain why the elementary (lowest order) fragmentation process q{yields}q{pi} is completely inadequate to describe the empirical data, although the crossed process {pi}{yields}qq describes the quark distribution functions in the pion reasonably well. Taking into account cascadelike processes in a generalized jet-model approach, we then show that the momentum and isospin sum rules can be satisfied naturally, without the introduction of ad hoc parameters. We present results for the Nambu-Jona-Lasinio (NJL) model in the invariant mass regularization scheme and compare them with the empirical para