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Sample records for pellet injector results

  1. Tritium pellet injector results

    International Nuclear Information System (INIS)

    Fisher, P.W.; Bauer, M.L.; Baylor, L.R.; Deleanu, L.E.; Fehling, D.T.; Milora, S.L.; Whitson, J.C.

    1988-01-01

    Injection of solid tritium pellets is considered to be the most promising way of fueling fusion reactors. The Tritium Proof-of- Principle (TPOP) experiment has demonstrated the feasibility of forming and accelerating tritium pellets. This injector is based on the pneumatic pipe-gun concept, in which pellets are formed in situ in the barrel and accelerated with high-pressure gas. This injector is ideal for tritium service because there are no moving parts inside the gun and because no excess tritium is required in the pellet production process. Removal of 3 He from tritium to prevent blocking of the cryopumping action by the noncondensible gas has been demonstrated with a cryogenic separator. Pellet velocities of 1280 m/s have been achieved for 4-mm-diam by 4-mm-long cylindrical tritium pellets with hydrogen propellant at 6.96 MPa (1000 psi). 10 refs., 10 figs

  2. Pellet injectors for JET

    International Nuclear Information System (INIS)

    Andelfinger, C.; Buechl, K.; Lang, R.S.; Schilling, H.B.; Ulrich, M.

    1981-09-01

    Pellet injection for the purpose of refuelling and diagnostic of fusion experiments is considered for the parameters of JET. The feasibility of injectors for single pellets and for quasistationary refuelling is discussed. Model calculations on pellet ablation with JET parameters show the required pellet velocity ( 3 ). For single pellet injection a light gas gun, for refuelling a centrifuge accelerator is proposed. For the latter the mechanical stress problems are discussed. Control and data acquisition systems are outlined. (orig.)

  3. Deuterium pellet injector gun design

    International Nuclear Information System (INIS)

    Lunsford, R.V.; Wysor, R.B.; Bryan, W.E.; Shipley, W.D.; Combs, S.K.; Foust, C.R.; Milora, S.L.; Fisher, P.W.

    1985-01-01

    The Deuterium Pellet Injector (DPI), an eight-pellet pneumatic injector, is being designed and fabricated for the Tokamak Fusion Test Reactor (TFTR). It will accelerate eight pellets, 4 by 4 mm maximum, to greater than 1500 m/s. It utilizes a unique pellet-forming mechanism, a cooled pellet storage wheel, and improved propellant gas scavenging

  4. Tritium pellet injector for TFTR

    International Nuclear Information System (INIS)

    Gouge, M.J.; Baylor, L.R.; Cole, M.J.; Combs, S.K.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foust, C.R.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Wilgen, J.B.; Schmidt, G.L.; Barnes, G.W.; Persing, R.G.

    1992-01-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) phase. The existing TFTR deuterium pellet injector (DPI) has been modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed to provide pellets ranging from 3.3 to 4.5 mm in diameter in arbitrarily programmable firing sequences at speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller. The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed, and the TPI was tested at ORNL with deuterium pellet. Results of the limited testing program at ORNL are described. The TPI is being installed on TFTR to support the D-D run period in 1992. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and secondary tritium containment systems and integrated into TFTR tritium processing systems to provide full tritium pellet capability

  5. Tritium proof-of-principle pellet injector results

    International Nuclear Information System (INIS)

    Fisher, P.W.; Fehling, D.T.; Gouge, M.J.; Milora, S.L.

    1989-01-01

    The tritium proof-of-principle (TPOP) experiment was built by Oak Ridge National Laboratory (ORNL) to demonstrate the feasibility of forming solid tritium pellets and accelerating them to high velocities for fueling future fusion reactors. TPOP used a pneumatic pipe-gun with a 4-mm-i.d. by 1-m-long barrel. Nearly 1500 pellets were fired by the gun during the course of the experiment; about a third of these were tritium or mixtures of deuterium and tritium. The system also contained a cryogenic 3 He separator that reduced the 3 He level to <0.005%. Pure tritium pellets were accelerated to 1400 m/s. Experiments evaluated the effect of cryostat temperature and fill pressure on pellet size, the production of pellets from mixtures of tritium and deuterium, and the effect of aging on pellet integrity. The tritium phase of these experiments was performed at the Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory. About 100 kCi of tritium was processed through the apparatus without incident. 8 refs., 7 figs

  6. Pellet injectors for steady state plasma fuelling

    International Nuclear Information System (INIS)

    Vinyar, I.; Geraud, A.; Yamada, H.; Lukin, A.; Sakamoto, R.; Skoblikov, S.; Umov, A.; Oda, Y.; Gros, G.; Krasilnikov, I.; Reznichenko, P.; Panchenko, V.

    2005-01-01

    Successful steady state operation of a fusion reactor should be supported by repetitive pellet injection of solidified hydrogen isotopes in order to produce high performance plasmas. This paper presents pneumatic pellet injectors and its implementation for long discharge on the LHD and TORE SUPRA, and a new centrifuge pellet injector test results. All injectors are fitted with screw extruders well suited for steady state operation

  7. Pneumatic pellet injector for JET

    International Nuclear Information System (INIS)

    Andelfinger, C.; Buechl, K.; Jacobi, D.; Sandmann, W.; Schiedeck, J.; Schilling, H.B.; Weber, G.

    1983-07-01

    Pellet injection is a useful tool for plasma diagnostics of tokamaks. Pellets can be applied for investigation of particle, energy and impurity transport, fueling efficiency and magnetic surfaces. Design, operation and control of a single shot pneumatic pellet gun is described in detail including all supplies, the vacuum system and the diagnostics of the pellet. The arrangement of this injector in the torus hall and the interfaces to the JET system and CODAS are considered. A guide tube system for pellet injection is discussed but it will not be recommended for JET. (orig.)

  8. Pellet injector development at ORNL

    International Nuclear Information System (INIS)

    Milora, S.L.; Argo, B.E.; Baylor, L.R.; Cole, M.J.; Combs, S.K.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Gouge, M.J.; Jernigan, T.C.; Langley, R.A.; Qualls, A.L.; Schechter, D.E.; Sparks, D.O.; Tsai, C.C.; Whealton, J.H.; Wilgen, J.B.; Schmidt, G.L.

    1992-01-01

    Plasma fueling systems for magnetic confinement experiments are under development at Oak Ridge National Laboratory (ORNL). ORNL has recently provided a four-shot tritium pellet injector with up to 4-mm-diam capability for the Tokamak Fusion Test Reactor (TFTR). This injector, which is based on the in situ condensation technique for pellet formation, features three single-stage gas guns that have been qualified in deuterium at up to 1.7 km/s and a two-stage light gas gun driver that has been operated at 2.8-km/s pellet speeds for deep penetration in the high-temperature TFTR supershot regime. Performance improvements to the centrifugal pellet injector for the Tore Supra tokamak are being made by modifying the storage-type pellet feed system, which has been redesigned to improve the reliability of delivery of pellets and to extend operation to longer pulse durations (up to 400 pellets). Two-stage light gas guns and electron-beam (e-beam) rocket accelerators for speeds in the range from 2 to 10 km/s are also under development. A repeating, two-stage light gas gun that has been developed can accelerate low-density plastic pellets at a 1-Hz repetition rate to speeds of 3 km/s. In a collaboration with ENEA-Frascati, a test facility has been prepared to study repetitive operation of a two-stage gas gun driver equipped with an extrusion-type deuterium pellet source. Extensive testing of the e-beam accelerator has demonstrated a parametric dependence of propellant burn velocity and pellet speed, in accordance with a model derived from the neutral gas shielding theory for pellet ablation in a magnetized plasma

  9. Centrifuge pellet injector for JET

    International Nuclear Information System (INIS)

    Andelfinger, C.; Buchelt, E.; Jacobi, D.; Lackner, E.; Schilling, H.B.; Ulrich, M.; Weber, G.

    1983-08-01

    An engineering design of a centrifuge pellet injector for JET is reported as part of the Phase I contract number JE 2/9016. A rather detailed design is presented for the mechanical and electronic features. Stress calculations, dynamic behaviour and life estimates are considered. The interfaces to the JET vacuum system and CODAS are discussed. Proposals for the pellet diagnostics (velocity, mass and shape) are presented. (orig.)

  10. Electrothermal plasma gun as a pellet injector

    International Nuclear Information System (INIS)

    Kincaid, R.W.; Bourham, M.A.

    1994-01-01

    The NCSU electrothermal plasma gun SIRENS has been used to accelerate plastic (Lexan polycarbonate) pellets, to determine the feasibility of the use of electrothermal guns as pellet injectors. The use of an electrothermal gun to inject frozen hydrogenic pellets requires a mechanism to provide protective shells (sabots) for shielding the pellet from ablation during acceleration into and through the barrel of the gun. The gun has been modified to accommodate acceleration of the plastic pellets using special acceleration barrels equipped with diagnostics for velocity and position of the pellet, and targets to absorb the pellet's energy on impact. The length of the acceleration path could be varied between 15 and 45 cm. The discharge energy of the electrothermal gun ranged from 2 to 6 kJ. The pellet velocities have been measured via a set of break wires. Pellet masses were varied between 0.5 and 1.0 grams. Preliminary results on 0.5 and 1.0 g pellets show that the exit velocity reaches 0.9 km/s at 6 kJ input energy to the source. Higher velocities of 1.5 and 2.7 km/s have been achieved using 0.5 and 1.0 gm pellets in 30 cm long barrel, without cleaning the barrel between the shots

  11. Pellet injector research at ORNL

    International Nuclear Information System (INIS)

    Combs, S.K.; Foster, C.A.; Milora, S.L.

    1988-01-01

    Advanced plasma fueling systems for magnetic confinement devices are under development a the Oak Ridge National Laboratory (ORNL). The general approach is that of producing and accelerating frozen hydrogen isotope pellets at speeds in the range 1-2 km/s and higher. Recently, ORNL provided pneumataic-based pellet fueling systems for two of the world's largest tokamak experiments, the Tokamak Fusion Test Reactor (TFTR) and the Joint European Torus (JET). A new versatile centrifuge type injector is being readied at ORNL for use on the Tore Supra tokamak. Also, a new simplified eight-shot injector design has been developed for use on the Princeton Beta Experiment (PBX) and the Advanced Toroidal Facility (ATF). In addition to these confinement physics related activities, ORNL is pursuing advanced technologies to achieve pellet velocities significantly in excess of 2 km/s and is carrying out a Tritium Proof-of-Principle (TPOP) experiment in which the fabrication and acceleration of tritium pellets have already been demonstrated. This paper describes these ongoing activities. 25 refs., 9 figs

  12. Solid deuterium centrifuge pellet injector

    International Nuclear Information System (INIS)

    Foster, C.A.

    1982-01-01

    Pellet injectors are needed to fuel long pulse tokamak plasmas and other magnetic confinement devices. For this purpose, an apparatus has been developed that forms 1.3-mm-diam pellets of frozen deuterium at a rate of 40 pellets per second and accelerates them to a speed of 1 km/s. Pellets are formed by extruding a billet of solidified deuterium through a 1.3-mm-diam nozzle at a speed of 5 cm/s. The extruding deuterium is chopped with a razor knife, forming 1.3-mm right circular cylinders of solid deuterium. The pellets are accelerated by synchronously injecting them into a high speed rotating arbor containing a guide track, which carries them from a point near the center of rotation to the periphery. The pellets leave the wheel after 150 0 of rotation at double the tip speed. The centrifuge is formed in the shape of a centrifugal catenary and is constructed of high strength KEVLAR/epoxy composite. This arbon has been spin-tested to a tip speed of 1 km/s

  13. Solid deuterium centrifuge pellet injector

    International Nuclear Information System (INIS)

    Foster, C.A.

    1983-01-01

    Pellet injectors are needed to fuel long pulse tokamak plasmas and other magnetic confinement devices. For this purpose, an apparatus has been developed that forms 1.3-mm-diam pellets of frozen deuterium at a rate of 40 pellets per second and accelerates them to a speed of 1 km/s. Pellets are formed by extruding a billet of solidified deuterium through a 1.3-mm-diam nozzle at a speed of 5 cm/s. The extruding deuterium is chopped with a razor knife, forming 1.3-mm right circular cylinders of solid deuterium. The pellets are accelerated by synchronously injecting them into a high speed rotating arbor containing a guide track, which carries them from a point near the center of rotation to the periphery. The pellets leave the wheel after 150 0 of rotation at double the tip speed. The centrifuge is formed in the shape of a centrifugal catenary and is constructed of high strength Kevlar/epoxy composite. This arbor has been spin-tested to a tip speed of 1 km/s

  14. Lithium Pellet Injector Development for NSTX

    International Nuclear Information System (INIS)

    Gettelfinger, G.; Dong, J.; Gernhardt, R.; Kugel, H.; Sichta, P.; Timberlake, J.

    2003-01-01

    A pellet injector suitable for the injection of lithium and other low-Z pellets of varying mass into plasmas at precise velocities from 5 to 500 m/s is being developed for use on NSTX (National Spherical Torus Experiment). The ability to inject low-Z impurities will significantly expand NSTX experimental capability for a broad range of diagnostic and operational applications. The architecture employs a pellet-carrying cartridge propelled through a guide tube by deuterium gas. Abrupt deceleration of the cartridge at the end of the guide tube results in the pellet continuing along its intended path, thereby giving controlled reproducible velocities for a variety of pellets materials and a reduced gas load to the torus. The planned injector assembly has four hundred guide tubes contained in a rotating magazine with eight tubes provided for injection into plasmas. A PC-based control system is being developed as well and will be described elsewhere in these Proceedings. The development path and mechanical performance of the injector will be described

  15. Pneumatic pellet injector for JT-60

    International Nuclear Information System (INIS)

    Onozuka, Masanori; Hiratsuka, Hajime; Kawasaki, Kouzo.

    1990-01-01

    The pneumatic 4-shot pellet injector has been installed and operated for JT-60 (JAERI Tokamak-60). The performance tests have proven that the device provides high speed pellets as planned. The maximum pellet velocity obtained in the hydrogen pellet tests is greater than 2.3km/s at 100 bar propellant gas. (author)

  16. Pneumatic pellet injector for JT-60

    Energy Technology Data Exchange (ETDEWEB)

    Onozuka, Masanori (Mitsubishi Heavy Industries Ltd., Tokyo (Japan)); Hiratsuka, Hajime; Kawasaki, Kouzo

    1990-11-01

    The pneumatic 4-shot pellet injector has been installed and operated for JT-60 (JAERI Tokamak-60). The performance tests have proven that the device provides high speed pellets as planned. The maximum pellet velocity obtained in the hydrogen pellet tests is greater than 2.3km/s at 100 bar propellant gas. (author).

  17. Pellet injector development and experiments at ORNL

    International Nuclear Information System (INIS)

    Baylor, L.R.; Argo, B.E.; Barber, G.C.; Combs, S.K.; Cole, M.J.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Gouge, M.J.; Jernigan, T.C.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Schechter, D.E.; Sparks, D.O.; Tsai, C.C.; Wilgen, J.B.; Whealton, J.H.

    1993-01-01

    The development of pellet injectors for plasma fueling of magnetic confinement fusion experiments has been under way at Oak Ridge National Laboratory (ORNL) for the past 15 years. Recently, ORNL provided a tritium-compatible four-shot pneumatic injector for the Tokamak Fusion Test Reactor (TFTR) based on the in situ condensation technique that features three single-stage gas guns and an advanced two-stage light gas gun driver. In another application, ORNL supplied the Tore Supra tokamak with a centrifuge pellet injector in 1989 for pellet fueling experiments that has achieved record numbers of injected pellets into a discharge. Work is progressing on an upgrade to that injector to extend the number of pellets to 400 and improve pellet repeatability. In a new application, the ORNL three barrel repeating pneumatic injector has been returned from JET and is being readied for installation on the DIII-D device for fueling and enhanced plasma performance experiments. In addition to these experimental applications, ORNL is developing advanced injector technologies, including high-velocity pellet injectors, tritium pellet injectors, and long-pulse feed systems. The two-stage light gas gun and electron-beam-driven rocket are the acceleration techniques under investigation for achieving high velocity. A tritium proof-of-principle (TPOP) experiment has demonstrated the feasibility of tritium pellet production and acceleration. A new tritium-compatible, extruder-based, repeating pneumatic injector is being fabricated to replace the pipe gun in the TPOP experiment and will explore issues related to the extrudability of tritium and acceleration of large tritium pellets. The tritium pellet formation experiments and development of long-pulse pellet feed systems are especially relevant to the International Tokamak Engineering Reactor (ITER)

  18. Pneumatic pellet injectors for TFTR and JET

    International Nuclear Information System (INIS)

    Combs, S.K.; Milora, S.L.

    1986-01-01

    This paper describes the development of pneumatic hydrogen pellet injectors for plasma fueling applications on the Tokamak Fusion Test Reactor (TFTR) and the Joint European Torus (JET). The performance parameters of these injectors represent an extension of previous experience and include pellet sizes in the range 2-6 mm in diameter and speeds approaching 2 km/s. Design features and operating characteristics of these pneumatic injectors are presented

  19. Tritium proof-of-principle pellet injector

    International Nuclear Information System (INIS)

    Fisher, P.W.

    1991-07-01

    The tritium proof-of-principle (TPOP) experiment was designed and built by Oak Ridge National Laboratory (ORNL) to demonstrate the formation and acceleration of the world's first tritium pellets for fueling of future fusion reactors. The experiment was first used to produce hydrogen and deuterium pellets at ORNL. It was then moved to the Tritium Systems Test Assembly at Los Alamos National Laboratory for the production of tritium pellets. The injector used in situ condensation to produce cylindrical pellets in a 1-m-long, 4-mm-ID barrel. A cryogenic 3 He separator, which was an integral part of the gun assembly, was capable of lowering 3 He levels in the feed gas to <0.005%. The experiment was housed to a glovebox for tritium containment. Nearly 1500 pellets were produced during the course of the experiment, and about a third of these were pure tritium or mixtures of deuterium and tritium. Over 100 kCi of tritium was processed through the experiment without incident. Tritium pellet velocities of 1400 m/s were achieved with high-pressure hydrogen propellant. The design, operation, and results of this experiment are summarized. 34 refs., 44 figs., 3 tabs

  20. Table-top pellet injector (TATOP) for impurity pellet injection

    Energy Technology Data Exchange (ETDEWEB)

    Szepesi, Tamás, E-mail: szepesi.tamas@wigner.mta.hu [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary); Herrmann, Albrecht [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany); Kocsis, Gábor; Kovács, Ádám; Németh, József [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary); Ploeckl, Bernhard [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany)

    2015-10-15

    Highlights: • A portable pellet injector for solid state pellets was designed. • Aims to study ELM triggering potential of impurity pellets. • Aims for multi-machine comparison of pellet–plasma interaction. • Max. pellet speed: 450 m/s, max. rate: 25 Hz. • Pellet size: 0.5–1.5 mm (diameter). - Abstract: A table-top pellet injector (TATOP) has been designed to fulfill the following scientific aims: to study the ELM triggering potential of impurity pellets, and to make pellet injection experiments comparable over several fusion machines. The TATOP is based on a centrifugal accelerator therefore the complete system is run in vacuum, ensuring the compatibility with fusion devices. The injector is able to launch any solid material (stable at room temperature) in form of balls with a diameter in the 0.5–1.5 mm range. The device hosts three individual pellet tanks that can contain e.g. pellets of different materials, and the user can select from those without opening the vacuum chamber. A key element of the accelerator is a two-stage stop cylinder that reduces the spatial scatter of pellets exiting the acceleration arm below 6°, enabling the efficient collection of all fired pellets. The injector has a maximum launch speed of 450 m/s. The launching of pellets can be done individually by providing TTL triggers for the injector, giving a high level of freedom for the experimenter when designing pellet trains. However, the (temporary) firing rate cannot be larger than 25 Hz. TATOP characterization was done in a test bed; however, the project is still in progress and before application at a fusion oriented experiment.

  1. Development of railgun pellet injector using a laser-induced plasma armature. Results of dummy pellet acceleration tests

    International Nuclear Information System (INIS)

    Onozuka, Masanori; Oda, Yasushi; Azuma, Kingo; Ogino, Mutsuo

    1995-01-01

    Using the low electric energy railgun system, dummy pellet acceleration tests have been conducted to investigate the application of the electromagnetic railgun system for high-speed pellet injection into fusion plasmas. The primary objective of the development is to improve the pellet acceleration efficiency and durability of the rail materials. In the system, the pellet is pre-accelerated before railgun acceleration. A laser beam is used to induce plasma armature. The ignited plasma armature is accelerated by an electromagnetic force that accelerates the pellet. As low electric energy was used, rail materials were used for multiple operations. Tungsten-alloy rail provided longer durability and slightly higher energy conversion coefficient than copper rail. The energy conversion coefficient was from 0.3 to 0.5% using a plastic insulator. A ceramic insulator improved the energy conversion coefficient by 80%. The highest pellet velocity was 1.7 km/s using wooden pellets accelerated by 1m-long railgun. Based on the findings, it is estimated that the hydrogen pellet has the potential to be accelerated to 5 km/s using a 3m-long railgun. (author)

  2. Development of railgun pellet injector using a laser-induced plasma armature. Results of dummy pellet acceleration tests

    Energy Technology Data Exchange (ETDEWEB)

    Onozuka, Masanori; Oda, Yasushi; Azuma, Kingo; Ogino, Mutsuo [Mitsubishi Heavy Industries Ltd., Yokohama (Japan). Nuclear Energy Systems Engineering Center

    1995-03-01

    Using the low electric energy railgun system, dummy pellet acceleration tests have been conducted to investigate the application of the electromagnetic railgun system for high-speed pellet injection into fusion plasmas. The primary objective of the development is to improve the pellet acceleration efficiency and durability of the rail materials. In the system, the pellet is pre-accelerated before railgun acceleration. A laser beam is used to induce plasma armature. The ignited plasma armature is accelerated by an electromagnetic force that accelerates the pellet. As low electric energy was used, rail materials were used for multiple operations. Tungsten-alloy rail provided longer durability and slightly higher energy conversion coefficient than copper rail. The energy conversion coefficient was from 0.3 to 0.5% using a plastic insulator. A ceramic insulator improved the energy conversion coefficient by 80%. The highest pellet velocity was 1.7 km/s using wooden pellets accelerated by 1m-long railgun. Based on the findings, it is estimated that the hydrogen pellet has the potential to be accelerated to 5 km/s using a 3m-long railgun. (author).

  3. Pellet injector research and development at ORNL

    International Nuclear Information System (INIS)

    Combs, S.K.; Barber, G.C.; Baylor, L.R.

    1994-01-01

    Oak Ridge National Laboratory has been developing pellet injectors for plasma fueling experiments on magnetic confinement devices for more than 15 years. Recent major applications of the ORNL development program include (1) a tritium-compatible four-shot pneumatic injector for the Tokamak Fusion Test Reactor, (2) a centrifuge pellet injector for the Tore Supra tokamak, and most recently (3) a three-barrel repeating pneumatic injector for the DIII-D tokamak. In addition to applications, ORNL is developing advanced technologies, including high-speed pellet injectors, tritium injectors, and long-pulse pellet feed systems. The high-speed research involves a collaboration between ORNL and ENEA-Frascati in the development of a repeating two-stage light gas gun based on an extrusion-type pellet feed system. Construction of a new tritium-compatible, extruder-based repeating pneumatic injector (8-mm-diam) is complete and will replace the pipe gun in the original tritium proof-of-principle experiment. The development of a steady-state feed system in which three standard extruders operate in tandem is under way. These research and development activities are relevant to the International Thermonuclear Experimental Reactor and are briefly described in this paper

  4. Repeating pneumatic pellet injector in JAERI

    International Nuclear Information System (INIS)

    Kasai, Satoshi; Hasegawa, Kouichi; Suzuki, Sadaaki; Miura, Yukitoshi; Oda, Yasushi; Onozuka, Masanori; Tsujimura, Seiichi.

    1992-09-01

    A repeating pneumatic pellet injector has been developed and constructed at Japan Atomic Energy Research Institute. This injector can provide repetitive pellet injection to fuel tokamak plasmas for an extended period of time, aiming at the improvement of plasma performance. The pellets with nearly identical speed and mass can be repeatedly injected with a repetition rate of 2-3.3 Hz and a speed of up to 1.7 km/s by controlling the temperature of the cryogenic system, the piston speed and the pressure of the propellant gas. (author)

  5. Repeating pneumatic pellet injector in JAERI

    Energy Technology Data Exchange (ETDEWEB)

    Kasai, Satoshi; Hasegawa, Kouichi; Suzuki, Sadaaki; Miura, Yukitoshi (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment); Oda, Yasushi; Onozuka, Masanori; Tsujimura, Seiichi.

    1992-09-01

    A repeating pneumatic pellet injector has been developed and constructed at Japan Atomic Energy Research Institute. This injector can provide repetitive pellet injection to fuel tokamak plasmas for an extended period of time, aiming at the improvement of plasma performance. The pellets with nearly identical speed and mass can be repeatedly injected with a repetition rate of 2-3.3 Hz and a speed of up to 1.7 km/s by controlling the temperature of the cryogenic system, the piston speed and the pressure of the propellant gas. (author).

  6. Pellet injector research and development at ORNL

    International Nuclear Information System (INIS)

    Combs, S.K.; Argo, B.E.; Baylor, L.R.; Cole, M.J.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Gouge, M.J.; Jernigan, T.C.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Schechter, E.; Sparks, D.O.; Tsai, C.C.; Wilgen, J.B.; Whealton, J.W.

    1993-01-01

    A variety of pellet injector designs have been developed at ORNL including single-shot guns that inject one pellet, multiple-shot guns that inject four and eight pellets, machine gun-types (single- and multiple-barrel) that can inject up to >100 pellets, and centrifugal accelerators (mechanical devices that are inherently capable of high repetition rates and long-pulse operation). With these devices, macroscopic pellets (1--6 mm in diameter) composed of hydrogen isotopes are typically accelerated to speeds of ∼1.0 to 2.0 km/s for injection into plasmas of experimental fusion devices. In the past few years, steady progress has been made at ORNL in the development and application of pellet injectors for fueling present-day and future fusion devices. In this paper, we briefly describe some research and development activities at ORNL, including: (1) two recent applications and a new one on large experimental fusion devices, (2) high-velocity pellet injector development, and (3) tritium injector research

  7. The JET multi-pellet injector launcher

    International Nuclear Information System (INIS)

    Kupschus, P.; Bailey, W.; Gadeberg, M.; Hedley, L.; Twyman, P.; Szabo, T.; Evans, D.

    1987-01-01

    Under a collaborative agreement between the Joint European Torus JET and the United States Department of Energy US DOE, JET and Oak Ridge National Laboratory (ORNL) jointly built a multi-pellet injector for fuelling and re-fuelling of the JET plasma. A three-barrel repetitive pneumatic pellet Launcher - built by ORNL - is attached to a JET pellet launcher-machine interface (in short: Pellet Interface) which is the subject of this paper. The present Launcher-Interface combination provides deuterium or hydrogen injection at moderate pellet speeds for the next two operational periods on JET. The Pellet Interface, however, takes into account the future requirements of JET. It was designed to allow the attachment of the high speed pellet launchers now under development at JET and complies with the requirements of remote handling and tritium operation. In addition, the use of tritium pellets is being considered

  8. Tritium pellet injector for the Tokamak Fusion Test Reactor

    International Nuclear Information System (INIS)

    Gouge, M.J.; Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foust, C.R.; Milora, S.L.

    1992-01-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) plasma phase. An existing deuterium pellet injector (DPI) was modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed for frozen pellets ranging in size from 3 to 4 mm in diameter in arbitrarily programmable firing sequences at tritium pellet speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller (PLC). The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were also made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed and the TPI was tested at ORNL with deuterium pellets. Results of the testing program at ORNL are described. The TPI has been installed and operated on TFTR in support of the CY-92 deuterium plasma run period. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and tritium gloveboxes and integrated into TFTR tritium processing systems to provide full tritium pellet capability

  9. Development of repeating pneumatic pellet injector

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Y.; Onozuka, M.; Shimomura, T. (Mitsubishi Heavy Industries Ltd., Kobe (Japan)) (and others)

    1990-01-01

    A repeating pneumatic pellet injector has been constructed to experiment with the technique of continuous injection for fueling fusion reactors. This device is composed of a cryogenic extruder and a gun assembly in (among others) a high-vacuum vessel, diagnostic vessels, LHe, fuel-gas and propellant-gas supply systems, control and data acquisition systems, etc. The performance tests, using hydrogen, have proved that the device provides the function of extruding frozen hydrogen ribbons at the speed of 6 mm s{sup -1}, chambering pellet at the rate of 5 Hz, and injecting pellet at the speed of 900 m s{sup -1}, as planned. (author).

  10. Development of repeating pneumatic pellet injector

    International Nuclear Information System (INIS)

    Oda, Y.; Onozuka, M.; Shimomura, T.

    1990-01-01

    A repeating pneumatic pellet injector has been constructed to experiment with the technique of continuous injection for fueling fusion reactors. This device is composed of a cryogenic extruder and a gun assembly in (among others) a high-vacuum vessel, diagnostic vessels, LHe, fuel-gas and propellant-gas supply systems, control and data acquisition systems, etc. The performance tests, using hydrogen, have proved that the device provides the function of extruding frozen hydrogen ribbons at the speed of 6 mm s -1 , chambering pellet at the rate of 5 Hz, and injecting pellet at the speed of 900 m s -1 , as planned. (author)

  11. The JET high frequency pellet injector project

    International Nuclear Information System (INIS)

    Geraud, Alain; Dentan, M.; Whitehead, A.; Butcher, P.; Communal, D.; Faisse, F.; Gedney, J.; Gros, G.; Guillaume, D.; Hackett, L.; Hennion, V.; Homfray, D.; Lucock, R.; McKivitt, J.; Sibbald, M.; Portafaix, C.; Perin, J.P.; Reade, M.; Sands, D.; Saille, A.

    2007-01-01

    A new deuterium ice pellet injector is in preparation for JET. It is designed to inject both small pellets (variable volume within 1-2 mm 3 ) at high frequency (up to 60 Hz) for ELM mitigation experiments and large pellets (volume within 35-70 mm 3 ) at moderate frequency (up to 15 Hz) for plasma fuelling. It is based on the screw extruder technology developed by PELIN and pneumatic acceleration. An injection line will connect the injector to the flight tubes already in place to convey the pellets toward the plasma either from the low field side or from the high field side of the torus. This injection line enables: (i) the pumping of the propellant gas, (ii) the provision of the vacuum interface with the torus and (iii) the selection of the flight tube to be used via a fast selector. All the interfaces have been designed and a prototype injector is being built, to demonstrate that the required performance is achievable

  12. Development of 4-shot pellet injector for JET-2M

    International Nuclear Information System (INIS)

    Noda, O.; Kuribayashi, S.; Uchikawa, T.; Onozuka, M.; Kasaki, S.; Hasegawa, K.

    1987-01-01

    A pneumatic 4 pellet injector has been constructed for JFT-2M. The performance tests have proved high performance and reliability of the injector. The maximum pellet velocity obtained in hydrogen pellet tests is 1.4km sec. The device is now in use for JFT-2M in a place of a previous single pellet injector, contributing to plasma studies. In this paper the outline of features and performance of the device is presented

  13. Repeating pneumatic hydrogen pellet injector for plasma fueling

    International Nuclear Information System (INIS)

    Combs, S.K.; Milora, S.L.; Foust, C.R.; Foster, C.A.; Schuresko, D.D.

    1985-01-01

    A repeating pneumatic pellet injector has been developed for plasma fueling applications. The repetitive device extends pneumatic injector operation to steady state. The active mechanism consists of an extruder and a gun assembly that are cooled by flowing liquid-helium refrigerant. The extruder provides a continuous supply of solid hydrogen to the gun assembly, where a reciprocating gun barrel forms and chambers cylindrical pellet from the extrusion; pellets are then accelerated with compressed hydrogen gas (pressures up to 125 bar) to velocities -1 have been obtained with 2.1- , 3.4- , and 4.0-mm-diameter pellets. The present apparatus operates at higher firing rates in short bursts; for example, a rate of 6 s -1 for 2 s with the larger pellets. These pellet parameters are in the range applicable for fueling large present-day fusion devices such as the Tokamak Fusion Test Reactor (TFTR). Experimental results are presented, including effects of propellant pressure and barrel length on gun performance

  14. Development of a pellet cutting and loading device for the JT-60 repetitive pellet injector

    International Nuclear Information System (INIS)

    Hiratsuka, Hajime; Ichige, Hisashi; Kizu, Kaname; Iwahashi, Takaaki; Honda, Masao

    2001-03-01

    In JT-60, a pellet injector that repetitively injects deuterium pellets is under development to supply fuel to high temperature plasmas and sustain high-density plasmas. The pellet injector generates cubic pellets and accelerates them with a straight-arm rotor by centrifugal force. In this acceleration method, it is important to supply pellets reliably and stably, to prevent pellet orbits from disordering and to stabilize the launching direction. To achieve higher performance of the injector, a pellet cutting and loading device that cuts a deuterium ice rod into cubic pellets and loads them to the pellet injector successively and stably has been developed. The pellet cutting and loading device can cut a deuterium ice rod produced at low temperature of -8 Pam 3 /s, cutting time of <3 ms, cutting frequency of 1-20 Hz and cutter stroke of 2.5 mm were confirmed in the device test. In the operation test after assembling this device to the centrifugal pellet injector, the operational performance of pellet injection frequency of ∼10 Hz, pellet speed of ∼690 m/s and pellet injection duration time of ∼3.5 s was achieved. Thus, the development of the pellet cutting and loading device contributed to the upgrade of the JT-60 pellet injector. (author)

  15. Pellet injectors for the tokamak fusion test reactor

    International Nuclear Information System (INIS)

    Combs, S.K.

    1986-01-01

    The repeating pneumatic injector is a device from the ORNL development program. A new eight-shot deuterium pellet injector has been designed and constructed specifically for the TFTR application and is scheduled to replace the repeating injector this year. The new device combines a cryogenic extruder and a cold wheel rotary mechanism to form and chamber eight pellets in a batch operation; the eight pellets can then be delivered in any time sequence. Another unique feature of the device is the variable pellet size with three pellets each of 3.0 and 3.5 mm diam and two each of 4.0 mm diam. The experience and technology that have been developed on previous injectors at ORNL have been utilized in the design of this latest pellet injection system

  16. Development of the centrifugal pellet injector for JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Kizu, Kaname; Hiratsuka, Hajime; Ichige, Hisashi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment] [and others

    2001-03-01

    For core fueling of JT-60U plasmas, a repetitive pellet injector which centrifugally accelerates D{sub 2} cubic pellets using a straight rod has been developed. This centrifugal pellet injector can eject trains of up to 40 cubic pellets at frequencies of 1-10 Hz and velocities of 0.3-1.0 km/s. The average pellet mass is 3.6x10{sup 20} atoms/pellet below 0.7 m/s. Key techniques for the development were a mesh structured acceleration component for removing gas sublimated from the pellet and a funnel with an appropriate angle connected just behind the acceleration chamber for introducing the pellet to plasma without destruction. Using the mesh structured components, the horizontal angular distribution of pellets ejected became narrow, because irregular pellet motion caused by sublimated gas was reduced. To investigate the performance of the injector, pellet injection experiments from the low magnetic field side (LFS) were conducted using ohmic heating plasmas. Central fueling and enhanced fueling rate have been observed. D{alpha} intensity around the divertor region was reduced in a pellet injection plasma compared to gas puffing, indicating low recycling rate was maintained with the pellet injection. (author)

  17. Development of the centrifugal pellet injector for JT-60U

    International Nuclear Information System (INIS)

    Kizu, Kaname; Hiratsuka, Hajime; Ichige, Hisashi

    2001-03-01

    For core fueling of JT-60U plasmas, a repetitive pellet injector which centrifugally accelerates D 2 cubic pellets using a straight rod has been developed. This centrifugal pellet injector can eject trains of up to 40 cubic pellets at frequencies of 1-10 Hz and velocities of 0.3-1.0 km/s. The average pellet mass is 3.6x10 20 atoms/pellet below 0.7 m/s. Key techniques for the development were a mesh structured acceleration component for removing gas sublimated from the pellet and a funnel with an appropriate angle connected just behind the acceleration chamber for introducing the pellet to plasma without destruction. Using the mesh structured components, the horizontal angular distribution of pellets ejected became narrow, because irregular pellet motion caused by sublimated gas was reduced. To investigate the performance of the injector, pellet injection experiments from the low magnetic field side (LFS) were conducted using ohmic heating plasmas. Central fueling and enhanced fueling rate have been observed. Dα intensity around the divertor region was reduced in a pellet injection plasma compared to gas puffing, indicating low recycling rate was maintained with the pellet injection. (author)

  18. The design and performance of a twenty barrel hydrogen pellet injector for Alcator C-Mod

    International Nuclear Information System (INIS)

    Urbahn, J.A.

    1994-05-01

    A twenty barrel hydrogen pellet injector has been designed, built and tested both in the laboratory and on the Alcator C-Mod Tokamak at MIT. The injector functions by firing pellets of frozen hydrogen or deuterium deep into the plasma discharge for the purpose of fueling the plasma, modifying the density profile and increasing the global energy confinement time. The design goals of the injector are: (1) Operational flexibility, (2) High reliability, (3) Remote operation with minimal maintenance. These requirements have lead to a single stage, pipe gun design with twenty barrels. Pellets are formed by in- situ condensation of the fuel gas, thus avoiding moving parts at cryogenic temperatures. The injector is the first to dispense with the need for cryogenic fluids and instead uses a closed cycle refrigerator to cool the thermal system components. The twenty barrels of the injector produce pellets of four different size groups and allow for a high degree of flexibility in fueling experiments. Operation of the injector is under PLC control allowing for remote operation, interlocked safety features and automated pellet manufacturing. The injector has been extrusively tested and shown to produce pellets reliably with velocities up to 1400 m/sec. During the period from September to November of 1993, the injector was successfully used to fire pellets into over fifty plasma discharges. Experimental results include data on the pellet penetration into the plasma using an advanced pellet tracking diagnostic with improved time and spatial response. Data from the tracker indicates pellet penetrations were between 30 and 86 percent of the plasma minor radius

  19. Development of H2 pellet injectors for industrial marketing

    International Nuclear Information System (INIS)

    Visler, T.

    1988-09-01

    1. Discussion of the construction of injector installation at ETA-BETA II. 2. Production and experience with two different ''pipe-guns''. One for large pellets, diameter/length = 4.5-5 mm/8-20 mm and one for small pellets, diameter/length = 2 mm/3-4 mm. (author) 27 ills., 39 refs

  20. Development and design of railgun system to pellet injector

    International Nuclear Information System (INIS)

    Oda, Y.; Onozuka, M.; Tsujjmura, S.; Kuribayashi, S.; Shimizu, K.C.; Tamura, H.; Sawaoka, A.

    1992-01-01

    In this paper, the railgun systems for the application of pellet injector are investigated and developed in the experimental stage. One of the main features of our railgun systems is to employ a pulse laser beam to induce the initial plasma armature between rails to be accelerated. This unique feature provides the reduction of the supplied voltage to the breakdown between the rails and to reduce the erosion of the rails. This paper presents the current results of a the authors' experimental and theoretical research progress, and introduces the design study for electromagnetic railgun based on our research progress

  1. Design of a tritium pellet injector for TFTR

    International Nuclear Information System (INIS)

    Milora, S.L.; Gouge, M.J.; Fisher, P.W.; Combs, S.K.; Cole, M.J.; Wysor, R.B.; Fehling, D.T.; Foust, C.R.; Baylor, L.R.; Schmidt, G.L.; Barnes, G.W.; Persing, R.G.

    1991-01-01

    The TFTR tritium pellet injector (TPI) is designed to provide a tritium pellet fueling capability with pellet speeds in the 1- to 3 km/s-range for the TFTR D-T phase. The existing TFTR deuterium pellet injector is being modified at Oak Ridge National Laboratory to provide a fourshot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns a two -stage light gas gun driver. The pipe gun concept has been qualified for tritium operation by the tritium proof-of-principle injector experiments conducted on the Tritium Systems Test Assembly at Los Alamos National Laboratory. In these experiments, tritium and D-T pellets were accelerated to speeds near 1.5 km/s. The TPI is being designed for pellet sizes in the range from 3.43 to 4.0 mm in diameter in arbitrarily programmable firing sequences at speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation will be controlled by a programmable logic controller. 7 refs., 4 figs

  2. A three-barrel repeating pneumatic pellet injector for plasma fueling of the Joint European Torus

    International Nuclear Information System (INIS)

    Combs, S.K.; Milora, S.L.; Baylor, L.R.; Foust, C.R.; Gethers, F.E.; Sparks, D.O.

    1987-01-01

    Pellet fueling, the injection of frozen hydrogen isotope pellets at high velocity, has been used to improve plasma performance in various tokamak experiments. In one recent experiment, the repeating pneumatic hydrogen pellet injector was used on the Tokamak Fusion Test Reactor (TFTR). This machine gun-like device, which was developed at the Oak Ridge National Laboratory (ORNL) with an objective of steady-state fueling applications, was characterized by a fixed pellet size and a maximum repetition rate of 4 to 6 Hz for several seconds. It was used to deliver deuterium pellets at speeds ranging from 1.0 to 1.5 km/s into TFTR plasma discharges. In the first experiments, injection of single, large (nominal 4-mm-diam) pellets provided high plasma densities in TFTR (1.8 x 10 14 cm -3 on axis). After a conversion to smaller (nominal 2.7-mm-diam) pellets, the pellet injector was operated in the repeating mode to gradually increase the plasma density, injecting up to five pellets on a single machine pulse. This resulted in central plasma densities approaching 4 x 10 14 cm -3 and n tau values of 1.4 x 10 14 cm -3 s. For plasma fueling applications on the Joint European Torus (JET), a pellet injector fashioned after the prototype repeating pneumatic design has been developed. The versatile injector features three repeating guns in a common vacuum enclosure; the guns provide pellets that are 2.7, 4.0, and 6.0 mm in diameter and can operate independently at repetition rates of 5, 2.5, and 1 Hz, respectively. The injector has been installed on JET. A description of the equipment is presented, emphasizing the differences from the original repeating device. Performance characteristics of the three pneumatic guns are also included

  3. Development of the pellet injector for JT-60

    International Nuclear Information System (INIS)

    Kawasaki, Kouzo; Hiratsuka, Hajimo; Takatsu, Hideyuki; Shimizu, Masatsugu; Onozuka, Masanori; Uchikawa, Takashi; Iwamoto, Syuichi; Hashiri, Nobuo

    1989-01-01

    The pneumatic 4-shot pellet injector has been installed and operated for JT-60 (JAERI Tokamak-60). The performance tests have proved that the device provides high speed hydrogen pellets just as planned. The maximum pellet velocity obtained in the hydrogen pellet tests is greater than 1.6 km/sec at 50 bar propellant gas. The device is now in use for JT-60 contributing to plasma study. In this paper the outline of features and performance of the device is presented. (author). 4 refs.; 8 figs

  4. Operation of the lithium pellet injector during D-T operations on TFTR

    International Nuclear Information System (INIS)

    Barnes, G.W.; Gernhardt, R.C.; Mansfield, D.

    1995-01-01

    The Lithium Pellet Injector is used as an operational tool to condition the vacuum vessel walls prior to and after plasma formation as well as to support diagnostics using the resulting neutral or spectral emissions. This paper addresses the injector operational issues that have been experienced during D-T experimental operations. Reliability enhancements are discussed, such as modification to the pellet magazine, gas purging and exhaust handling. Nuclear boundary line breaks for routine magazine wheel changeout are addressed. Procedures that were developed and utilized to ensure ALARA (As Low As Reasonably Achievable) during line breaks are discussed. Lithium loading of the pellet wheel and the special techniques that are required are described

  5. Development of fast opening magnetic valve for JT-60 pellet injector

    International Nuclear Information System (INIS)

    Hiratsuka, Hajime; Kawasaki, Kouzo; Takatsu, Hideyuki; Miyo, Yasuhiko; Yoshioka, Yuji; Ohta, Kazuya; Shimizu, Masatsugu; Onozuka, Masanori; Uchikawa, Takashi; Iwamoto, Syuichi; Hashiri, Noboru

    1989-01-01

    A pneumatic four-pellet injector (JT-60 pellet injector) has been constructed for JT-60 in May, 1988. A fast opening magnetically driven propellant gas injection valve has been developed for JT-60 pellet injector. This valve can accelerate four cylindrical pellets, two 3.8 mm diameter by 3.8 mm and two 2.7 mm diameter by 2.7 mm, to greater than 1.6 km/s with propellent gas of up to 50 bar. It is now successfully in use in JT-60, contributing to plasma studies. In this paper the outline of a newly developed fast opening magnetic valve and the results of performance tests are presented. (author). 6 figs.; 1 tab

  6. Development of a two-state pellet injector for Heliotron-E

    International Nuclear Information System (INIS)

    Sudo, S.; Baba, T.; Kanno, M.; Saka, S.

    1991-01-01

    This paper reports on a two-stage pellet injector for Heliotron-E that is constructed and tested. The aim is to increase pellet velocity for more flexible density profile control of the Heliotron-E plasma and also to conduct a pellet ablation study using a wider range of pellet velocity. The pellet velocity is limited to ∼1.4 km/s in the current six-pellet injector at Heliotron-E. The fundamental operation is simulated with the Quickgun code. The experimental results generally agree well (within 80 to 90%) with the code calculations. By using a newly developed high-pressure fast valve, a hydrogen pellet velocity of 3.2 km/s has been achieved, without a supportive shell or sabot to protect the pellet, although more tests are needed to confirm whether pellets can reliably be accelerated to this high speed without fracturing. The dependence of the pellet velocity and breech pressure on the pump tube fill pressure is studied. The results show that the fill pressure is an important parameter. The effect of the clearance between the piston and the pump tube wall on the pellet velocity is also investigated. The wear and damage of the piston caused by the compressing propellant gas are investigated. It is shown that changes on the piston surface when hydrogen is used for fill gas are different from the case of helium

  7. Operation of the lithium pellet injector

    International Nuclear Information System (INIS)

    Khlopenkov, K.V.; Sudo, S.; Sergeev, V.Yu.

    1996-05-01

    A lithium pellet injection requires an accurate handling with lithium and special technique of loading the pellets. Thus, the technology for this has been developed based on the following conditions: 1) Because of chemical activity of lithium it is necessary to operate in a glove-box with the noble gas atmosphere (He, Ar, etc.). 2) A special procedure of replacing the glove-box atmosphere allows to achieve high purity of the noble gas. 3) When making the pellets it is better to keep the clean lithium in the liquid hexane so as to maintain lithium purity. 4) The pressure of the accelerating gas for Li pellets should be not less than 30 atm. (author)

  8. Design considerations for single-stage and two-stage pneumatic pellet injectors

    International Nuclear Information System (INIS)

    Gouge, M.J.; Combs, S.K.; Fisher, P.W.; Milora, S.L.

    1988-09-01

    Performance of single-stage pneumatic pellet injectors is compared with several models for one-dimensional, compressible fluid flow. Agreement is quite good for models that reflect actual breech chamber geometry and incorporate nonideal effects such as gas friction. Several methods of improving the performance of single-stage pneumatic pellet injectors in the near term are outlined. The design and performance of two-stage pneumatic pellet injectors are discussed, and initial data from the two-stage pneumatic pellet injector test facility at Oak Ridge National Laboratory are presented. Finally, a concept for a repeating two-stage pneumatic pellet injector is described. 27 refs., 8 figs., 3 tabs

  9. Development of D2 Pellet Injectors

    DEFF Research Database (Denmark)

    Sørensen, H.; Andersen, S. A.; Nordskov Nielsen, A.

    1985-01-01

    A versatile extrusion-type pneumatic gun is described. The extrusion nozzle/gun barrel system can easily be exchanged to produce pellets in the diameter range 0.4—2.0 mm. Velocities in the range 0.1—1.35 km/s are obtained by adjusting the propeller gas pressure. It is proposed that this gun type ...

  10. Diagnostics and camera strobe timers for hydrogen pellet injectors

    International Nuclear Information System (INIS)

    Bauer, M.L.; Fisher, P.W.; Qualls, A.L.

    1993-01-01

    Hydrogen pellet injectors have been used to fuel fusion experimental devices for the last decade. As part of developments to improve pellet production and velocity, various diagnostic devices were implemented, ranging from witness plates to microwave mass meters to high speed photography. This paper will discuss details of the various implementations of light sources, cameras, synchronizing electronics and other diagnostic systems developed at Oak Ridge for the Tritium Proof-of-Principle (TPOP) experiment at the Los Alamos National Laboratory's Tritium System Test Assembly (TSTA), a system built for the Oak Ridge Advanced Toroidal Facility (ATF), and the Tritium Pellet Injector (TPI) built for the Princeton Tokamak Fusion Test Reactor (TFTR). Although a number of diagnostic systems were implemented on each pellet injector, the emphasis here will be on the development of a synchronization system for high-speed photography using pulsed light sources, standard video cameras, and video recorders. This system enabled near real-time visualization of the pellet shape, size and flight trajectory over a wide range of pellet speeds and at one or two positions along the flight path. Additionally, the system provides synchronization pulses to the data system for pseudo points along the flight path, such as the estimated plasma edge. This was accomplished using an electronic system that took the time measured between sets of light gates, and generated proportionally delayed triggers for light source strobes and pseudo points. Systems were built with two camera stations, one located after the end of the barrel, and a second camera located closer to the main reactor vessel wall. Two or three light gates were used to sense pellet velocity and various spacings were implemented on the three experiments. Both analog and digital schemes were examined for implementing the delay system. A digital technique was chosen

  11. Development of railgun pellet injector for nuclear fusion fueling

    International Nuclear Information System (INIS)

    Azuma, Kingo; Oda, Yasushi; Onozuka, Masanori.

    1996-01-01

    Recent fusion plasmas have become larger as fusion research progresses. This requires high-velocity solid-hydrogen pellet injection that is the most efficient fueling method. The application of the electro-magnetic railgun system for pellet injection is one of the most feasible technologies for accelerating a pellet to a high speed. The system consists of a pneumatic pre-accelerator for the first acceleration stage and a railgun for the second stage. The railgun is operated by a low voltage discharged from a pulse-forming-network power supply to accelerate a plasma armature between the rail electrodes. The plasma is induced by high-power laser beam irradiation. The highest velocity of a solid-hydrogen pellet obtained using the railgun was 2.6 km/s. This velocity is higher than the maximum pellet velocity of 2.3 km/s achieved by MHI's pneumatic pellet injector. It was also found that the pellet velocity could be controlled easily using railgun pellet injection. (author)

  12. Development of railgun pellet injector for nuclear fusion fueling

    Energy Technology Data Exchange (ETDEWEB)

    Azuma, Kingo [Mitsubishi Heavy Industries Ltd., Takasago, Hyogo Takasago Research and Development Center (Japan); Oda, Yasushi; Onozuka, Masanori

    1996-03-01

    Recent fusion plasmas have become larger as fusion research progresses. This requires high-velocity solid-hydrogen pellet injection that is the most efficient fueling method. The application of the electro-magnetic railgun system for pellet injection is one of the most feasible technologies for accelerating a pellet to a high speed. The system consists of a pneumatic pre-accelerator for the first acceleration stage and a railgun for the second stage. The railgun is operated by a low voltage discharged from a pulse-forming-network power supply to accelerate a plasma armature between the rail electrodes. The plasma is induced by high-power laser beam irradiation. The highest velocity of a solid-hydrogen pellet obtained using the railgun was 2.6 km/s. This velocity is higher than the maximum pellet velocity of 2.3 km/s achieved by MHI`s pneumatic pellet injector. It was also found that the pellet velocity could be controlled easily using railgun pellet injection. (author).

  13. SPINS-IND: Pellet injector for fuelling of magnetically confined fusion systems

    Science.gov (United States)

    Gangradey, R.; Mishra, J.; Mukherjee, S.; Panchal, P.; Nayak, P.; Agarwal, J.; Saxena, Y. C.

    2017-06-01

    Using a Gifford-McMahon cycle cryocooler based refrigeration system, a single barrel hydrogen pellet injection (SPINS-IND) system is indigenously developed at Institute for Plasma Research, India. The injector is based on a pipe gun concept, where a pellet formed in situ in the gun barrel is accelerated to high speed using high pressure light propellant gas. The pellet size is decided by considering the Greenwald density limit and its speed is decided by considering a neutral gas shielding model based scaling law. The pellet shape is cylindrical of dimension (1.6 mm ℓ × 1.8 mm φ). For pellet ejection and acceleration, a fast opening valve of short opening duration is installed at the breech of the barrel. A three-stage differential pumping system is used to restrict the flow of the propellant gas into the plasma vacuum vessel. Diagnostic systems such as light gate and fast imaging camera (240 000 frames/s) are employed to measure the pellet speed and size, respectively. A trigger circuit and a programmable logic controller based integrated control system developed on LabVIEW enables to control the pellet injector remotely. Using helium as a propellant gas, the pellet speed is varied in the range 650 m/s-800 m/s. The reliability of pellet formation and ejection is found to be more than 95%. This paper describes the details of SPINS-IND and its test results.

  14. Pellet injector development at ORNL [Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Gouge, M.J.; Argo, B.E.; Baylor, L.R.; Combs, S.K.; Fehling, D.T.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Milora, S.L.; Qualls, A.L.; Schechter, D.E.; Simmons, D.W.; Sparks, D.O.; Tsai, C.C.

    1990-01-01

    Advanced plasma fueling systems for magnetic confinement experiments are under development at Oak Ridge National Laboratory (ORNL). The general approach is that of producing and accelerating frozen hydrogenic pellets to speeds in the kilometer-per-second range by either pneumatic (light-gas gun) or mechanical (centrifugal force) techniques. ORNL has recently provided a centrifugal pellet injector for the Tore Supra tokamak and a new, simplified, eight-shot pneumatic injector for the Advanced Toroidal Facility stellarator at ORNL. Hundreds of tritium and DT pellets were accelerated at the Tritium Systems Test Assembly facility at Los Alamos in 1988--89. These experiments, done in a single-shot pipe-gun system, demonstrated the feasibility of forming and accelerating tritium pellets at low 3 He levels. A new, tritium-compatible extruder mechanism is being designed for longer-pulse DT applications. Two-stage light-gas guns and electron beam rocket accelerators for speeds of the order of 2--10 km/s are also under development. Recently, a repeating, two-stage light-gas gun accelerated 10 surrogate pellets at a 1-Hz repetition rate to speeds in the range of 2--3 km/s; and the electron beam rocket accelerator completed initial feasibility and scaling experiments. ORNL has also developed conceptual designs of advanced plasma fueling systems for the Compact Ignition Tokamak and the International Thermonuclear Experimental Reactor

  15. Control System for the NSTX Lithium Pellet Injector

    International Nuclear Information System (INIS)

    Sichta, P.; Dong, J.; Gernhardt, R.; Gettelfinger, G.; Kugel, H.

    2003-01-01

    The Lithium Pellet Injector (LPI) is being developed for the National Spherical Torus Experiment (NSTX). The LPI will inject ''pellets'' of various composition into the plasma in order to study wall conditioning, edge impurity transport, liquid limiter simulations, and other areas of research. The control system for the NSTX LPI has incorporated widely used advanced technologies, such as LabVIEW and PCI bus I/O boards, to create a low-cost control system which is fully integrated into the NSTX computing environment. This paper will present the hardware and software design of the computer control system for the LPI

  16. Tritium pellet injector design for tokamak fusion test reactor

    International Nuclear Information System (INIS)

    Fisher, P.W.; Baylor, L.R.; Bryan, W.E.

    1985-01-01

    A tritium pellet injector (TPI) system has been designed for the Tokamak Fusion Test Reactor (TFTR) Q approx. 1 phase of operation. The injector gun utilizes a radial design with eight independent barrels and a common extruder to minimize tritium inventory. The injection line contains guide tubes with intermediate vacuum pumping stations and fast valves to minimize propellant leakage to the torus. The vacuum system is designed for tritium compatibility. The entire injector system is contained in a glove box for secondary containment protection against tritium release. Failure modes and effects have been analyzed, and structural analysis has been performed for most intense predicted earthquake conditions. Details of the design and operation of this system are presented in this paper

  17. Development of upgraded pellet injector for JT-60

    International Nuclear Information System (INIS)

    Onozuka, M.; Shimomura, T.; Tanaka, N.; Iwamoto, S.; Hashiri, N.; Oda, Y.; Minami, M.; Hiratsuka, H.; Kawasaki, K.; Takatsu, H.; Shimizu, M.

    1989-01-01

    The pneumatic 4-shot pellet injector had been in use for JT-60 (JAERI Tokamak-60) contributing to plasma studies in 1988. It could propel the pellets up to 1.6 km/sec at 50 bar propellant gas. In 1989, the new gun assembly has been reinstalled in the upgraded system to provide higher performance and reliability. The supply pressure of the propellant gas is to be raised to 100 bar to obtain higher pellet velocity up to 2.3 km/sec. The device is now in use for JT-60, and is expected to contribute to further plasma studies. In this paper the outline of features and performance of the device is presented. 5 refs., 9 figs

  18. 3400 m/s deuterium pellet injector for Tore Supra

    International Nuclear Information System (INIS)

    Perin, J.P.; Geraud, A.

    1995-01-01

    This paper reports on the Tore Supra high velocity pellet injector which was built in Grenoble and after qualification tests installed on Tore Supra Tokomak where it is used for plasma and ablation studies. By using a two stage light gas gun (TSG) and two cells (φ = 3 mm or 4 mm), unsupported pellets pellets (1 to 3.5 10 21 atoms) made directly in the gun by > [1] have been launched into Tore Supra plasma at speeds between 2400m/s and 3400m/s with a reliability of 80%. These higher pellets velocities (> 2500 m/s) [2] are obtained by the optimization of a TSG and the search for the cryogenic conditions of freezing deuterium with good mechanical properties. In particular, the impurities concentration in deuterium during the condensation process has been studied. Several tens pellets have been injected into ohmically and ICR heated plasma and during LH current drive experiments with a good reliability in the range of 3000m/s. These experiments allowed us to extend significantly the ablation data base. Central penetrations can be reached even for high temperatures plasma (3-5 keV) and very peaked density profiles have been obtained in ohmically and ICR heated plasmas A transient improved confinement regime is then observed, which presents some features similar to the PEP regime obtained on JET. (orig.)

  19. Design of deuterium and tritium pellet injector systems for Tokamak Fusion Test Reactor

    International Nuclear Information System (INIS)

    Wysor, R.B.; Baylor, L.R.; Bryan, W.E.

    1985-01-01

    Three pellet injector designs developed by the Oak Ridge National Laboratory (ORNL) are planned for the Tokamak Fusion Test Reactor (TFTR) to reach the goal of a tritium pellet injector by 1988. These are the Repeating Pneumatic Injector (RPI), the Deuterium Pellet Injector (DPI) and the Tritium Pellet Injector (TPI). Each of the pellet injector designs have similar performance characteristics in that they deliver up to 4-mm-dia pellets at velocities up to 1500 m/s with a dsign goal to 2000 m/s. Similar techniques are utilized to freeze and extrude the pellet material. The injector systems incorporate three gun concepts which differ in the number of gun barrels and the method of forming and chambering the pellets. The RPI, a single barrel repeating design, has been operational on TFTR since April 1985. Fabrication and assembly are essentially complete for DPI, and TPI is presently on hold after completing about 80% of the design. The TFTR pellet injector program is described, and each of the injector systems is described briefly. Design details are discussed in other papers at this symposium

  20. NLCTA injector experimental results

    International Nuclear Information System (INIS)

    Yeremian, A.D.; Adolphsen, C.; Miller, R.H.; Nantista, C.D.; Wang, J.W.

    1997-04-01

    The purpose of the Next Linear Collider Test Accelerator (NLCTA) at SLAC is to integrate the new technologies of X-band accelerator structures and RF systems for the Next Linear Collider (NLC), demonstrate multibunch beam-loading energy compensation and suppression of high-order deflecting modes, measure the transverse components of the accelerating field, and measure the dark current generated by RF field emission in the accelerator. For beam loading R and D, an average current of about 1 A in a 120 ns long bunch train is required. The initial commissioning of the NLCTA injector, as well as the rest of the accelerator have been progressing very well. The initial beam parameters are very close to the requirement and they expect that injector will meet the specified requirements by the end of this summer

  1. Operation of the repeating pneumatic injector on TFTR and design of an 8-shot deuterium pellet injector

    International Nuclear Information System (INIS)

    Combs, S.K.; Milora, S.L.; Foust, C.R.

    1985-01-01

    The repeating pneumatic hydrogen pellet injector, which was developed at the Oak Ridge National Laboratory (ORNL), has been installed and operated on the Tokamak Fusion Test Reactor (TFTR). The injector combines high-speed extruder and pneumatic acceleration technologies to propel frozen hydrogen isotope pellets repetitively at high speeds. The pellets are transported to the plasma in an injection line that also serves to minimize the gas loading on the torus; the injection line incorporates a fast shutter valve and two stages of guide tubes with intermediate vacuum pumping stations. A remote, stand-alone control and data acquisition system is used for injector and vacuum system operation. In early pellet fueling experiments on TFTR, the injector has been used to deliver deuterium pellets at speeds ranging from 1.0 to 1.5 km/s into plasma discharges. First, single large (nominal 4-mm-dia) pellets provided high densities in TFTR (1.8 x 10 14 cm -3 on axis); after conversion to smaller (nominal 2.7-mm-dia) pellets, up to five pellets were injected at 0.25-s intervals into a plasma discharge, giving a line-averaged density of 1 x 10 14 cm -3 . Operating characteristics and performance of the injector in initial tests on TFTR are presented

  2. Upgrading the JET pellet injector with a two-stage light gas gun prototype and future planning

    International Nuclear Information System (INIS)

    Kupschus, P.; Sonnenberg, K.; Bailey, W.; Gadeberg, M.; Hardaker, J.; Hedley, L.; Helm, J.; Flory, D.; McCarthy, P.; Nowak, A.; Twynam, P.; Szabo, T.; Watson, M.

    1989-01-01

    For about two years the Joint European TORUS (JET) has been using a multi-pellet injector jointly built by JET and the Oak Ridge National Laboratory (ORNL). This was and is jointly operated by a JET - US Pellet Team within the Pellet Agreement between JET and the US Department of Energy (US DOE) under the wider umbrella of the EURATOM - US DOE Agreement on collaborative Fusion Research. This injector is composed of the ORNL Launcher, employing three independently firing repetitive (up to 5 s -1 ) pneumatic guns for pellet speeds of up to 1.5 kms -1 , and a JET launcher-torus interface (Pellet Interface) which provides all required services to the launcher and its immediate control system. In particular, it provides the differential pumping to match the high pressures of the gun system to the vacuum pressure and flow requirements of the plasma boundary. The Pellet Interface, in its design from its conception about four years ago, was intended to be equipped with a JET built pellet launcher system employing also high-speed guns at a later date once the ORNL Launcher will have been removed as it is not compatible with the JET requirements for the Active Phase (tritium and remote handling compatibility). As a first step - to learn about the possible plasma physics benefits as well as to gain technical experience concerning the application of advanced gun technology, a JET two-stage light gas gun prototype has been developed and is now being installed in parallel with the ORNL Launcher. This paper reports on the JET pellet injector development program, its motivation and its results to date. It describes briefly the presently operated pellet injector, continues to outline the design of the prototype in more detail and finally sketches the plans for the near future. 8 refs., 11 figs., 1 tab

  3. The control system for the multiple-pellet injector on the Joint European Torus

    International Nuclear Information System (INIS)

    Baylor, L.R.; Jernigan, T.C.; Stewart, K.A.

    1989-01-01

    A stand-alone control and data acquisition system for the Oak Ridge National Laboratory (ORNL) multiple-pellet injector installed on the Joint European Torus (JET) has been designed and installed with the injector. This system, which is based on a MicroVAX II computer and a programmable logic controller (PLC), is an upgrade of previous systems designed for ORNL pellet injectors installed on other fusion experiments. The primary control system upgrades are in the user interface, in the automation of sequential injector operation, and in the analysis of the transient data acquired for each pellet fired. The system is integrated into the JET CODAS environment through CAMAC communications modules with customized communications software. Routine operation of the injector is automated and requires no operator intervention. Details of the hardware and software design and the operation of the system are presented in this paper. 4 refs., 3 figs

  4. Design and construction of hydrogen pellet injector by droplet-method

    International Nuclear Information System (INIS)

    Noda, Etsuo; Iida, Yoshiyuki; Sekiguchi, Tadashi; Suemori, Nobuo; Imaizumi, Hideki.

    1984-01-01

    A hydrogen pellet injector by a droplet-method has been constructed and studied, in order to realize a hydrogen-isotope pellet injector for refueling into nuclear fusion reactors, which can inject pellets into plasma repetitively. Preliminary experiments with oxygen gas, instead of hydrogen gas, has been systematically carried out. Assuming the liquid concerned as viscous fluid, theoretical predictions about droplet-diameter, its ejected velocity and optimum frequency of ejecting-nozzle vibration for stable droplet production has been made, and it is found that theoretical results are in good agreement with experimental ones. It is found that the stable droplet train can be obtained when the value of Reynolds number is in the range of 1,100--1,300. In the hydrogen experiments based upon the oxygen results, the production of a stable hydrogen liquid-droplet train, their self-solidification and transfer into a vacuum space through an orifice (with the diameter of 1 mm) have been successfully realized, by maintaining the gas pressure around the droplets at 45--50 Torr. (author)

  5. High-speed repetitive pellet injector for plasma fueling of magnetic confinement fusion devices

    International Nuclear Information System (INIS)

    Combs, S.K.; Baylor, L.R.; Foust, C.R.

    1993-01-01

    The projected fueling requirements of future magnetic confinement devices for controlled thermonuclear research [e.g., the International Thermonuclear Experimental Reactor (ITER)] indicate that a flexible plasma fueling capability is required. This includes a mix of traditional gas puffing and low- and high-velocity deuterium-tritium pellets. Conventional pellet injectors (based on light gas guns or centrifugal accelerators) can reliably provide frozen hydrogen pellets (1- to 6-mm-diam sizes tested) up to ∼1.3-km/s velocity at the appropriate pellet fueling rates (1 to 10 Hz or greater). For long-pulse operation in a higher velocity regime (>2 km/s), an experiment in collaboration between Oak Ridge National Laboratory (ORNL) and ENEA Frascati is under way. This activity will be carried out in the framework of a collaborative agreement between the US Department of Energy and European Atomic Energy Community -- ENEA Association. In this experiment, an existing ORNL hydrogen extruder (equipped with a pellet chambering mechanism/gun barrel assembly) and a Frascati two-stage light gas gun driver have been combined on a test facility at ORNL. Initial testing has been carried out with single deuterium pellets accelerated up to 2.05 km/s with the two-stage driver; in addition, some preliminary repetitive testing (to commission the diagnostics) was performed at reduced speeds, including sequences at 0.5 to 1 Hz and 10 to 30 pellets. The primary objective of this study is to demonstrate repetitive operation (up to ∼1 Hz) with speeds in the 2- to 3-km/s range. In addition, the strength of extruded hydrogen ice as opposed to that produced in situ by direct condensation in pipe guns can be investigated. The equipment and initial experimental results are described

  6. Review: study of single-pellet injection experiments and development of pellet injector in JFT-2M

    International Nuclear Information System (INIS)

    Kasai, Satoshi; Miura, Yukitoshi; Hasegawa, Kouichi; Sengoku, Seio

    1987-10-01

    The single pellet injector developed for JFT-2M and the improvement of plasma characteristics in the auxiliary-heated discharges by single-pellet injection are reviewed for the period 1982 - 1986. The pellet injector is a pneumatic type and the designed pellet size is 1.65 mmD x 1.65 mmL and 1 mmD x 1 mmL. The hydrogen, deuterium and mixed (H 2 + D 2 ) pellets can be produced with good reproducibility. Maximum pellet velocity is about 970 m/s (pellet is deuterium and propellant gas is hydrogen). In the pellet injection experiments into auxiliary-heated (NB, ICRF) divertor or limiter discharges, the plasma confinement time is improved by a factor of 1.4 - 1.7 compared with the confinement time in the Ohmic discharges. The achieved confinement time is longer than that on the high confinement mode (H-mode) in gas fueled discharges, although the phenomena are transient. (author)

  7. Fueling of magnetically confined plasmas by single- and two-stage repeating pneumatic pellet injectors

    International Nuclear Information System (INIS)

    Gouge, M.J.; Combs, S.K.; Foust, C.R.; Milora, S.L.

    1990-01-01

    Advanced plasma fueling systems for magnetic fusion confinement experiments are under development at Oak Ridge National Laboratory (ORNL). The general approach is that of producing and accelerating frozen hydrogenic pellets to speeds in the kilometer-per-second range using single shot and repetitive pneumatic (light-gas gun) pellet injectors. The millimeter-to-centimeter size pellets enter the plasma and continuously ablate because of the plasma electron heat flux, depositing fuel atoms along the pellet trajectory. This fueling method allows direct fueling in the interior of the hot plasma and is more efficient than the alternative method of injecting room temperature fuel gas at the wall of the plasma vacuum chamber. Single-stage pneumatic injectors based on the light-gas gun concept have provided hydrogenic fuel pellets in the speed range of 1--2 km/s in single-shot injector designs. Repetition rates up to 5 Hz have been demonstrated in repetitive injector designs. Future fusion reactor-scale devices may need higher pellet velocities because of the larger plasma size and higher plasma temperatures. Repetitive two-stage pneumatic injectors are under development at ORNL to provide long-pulse plasma fueling in the 3--5 km/s speed range. Recently, a repeating, two-stage light-gas gun achieved repetitive operation at 1 Hz with speeds in the range of 2--3 km/s

  8. Design and implementation of a control and data acquisition system for pellet injectors

    International Nuclear Information System (INIS)

    Baylor, L.R.; Burris, R.D.; Greenwood, D.E.; Stewart, K.A.

    1985-01-01

    A stand-alone control and data acquisition system for pellet injectors has been designed and implemented to support pellet injector development at Oak Ridge Laboratory (ORNL) and to enable ORNL pellet injectors to be installed on various fusion experimental devices. The stand-alone system permits LOCAL operation of the injector from a nearby panel and REMOTE operation from the experiment control room. Major components of the system are (1) an Allen-Bradley PLC 2/30 programmable controller, (2) a VAX minicomputer, and (3) a CAMAC serial highway interface. The programmable logic controller (PLC) is used to perform all control functions of the injector. In LOCAL, the operator interface is provided by an intelligent panel system that has a keypad and pushbutton module programmed from the PLC. In REMOTE, the operator interfaces via a VAX-based color graphics display and uses a trackball and keyboard to issue commands. Communications between the remote and local controls and to the fusion experiment supervisory system are via the CAMAC highway. The VAX archives transient data from pellet shots and trend data acquired from the PLC. Details of the hardware and software design and the operation of the system are presented in this paper. 3 refs., 1 fig

  9. Radiation analysis of the CIT (Compact Ignition Tokamak) pellet injector system and its impact on personnel access

    Energy Technology Data Exchange (ETDEWEB)

    Selcow, E.C.; Stevens, P.N.; Gomes, I.C.; Gomes, L.M.

    1987-01-01

    Conceptual design of the Compact Ignition Tokamak (CIT) is near completion. This short-pulse ignition experiment is planned to follow the operations of the Tokamak Fusion Test Reactor (TFTR) at the Princeton Plasma Physics Laboratory. The high neutron wall loadings, /approximately/4-5 MW/m/sup 2/, associated with the operation of this device require that neutronics-related issues be considered in the overall system design. Radiation shielding is required for the protection of device components and personnel. A close-in igloo shield has been designed around the periphery of the tokamak structure, and the entire experiment is housed in a circular test cell facility with a radius of /approximately/12 m. The most critical radiation concern in the CIT design process relates to the numerous penetrations in the device. This paper discusses the impact of a major penetration on the design and operations of the CIT pellet injection system. The pellet injector is a major component, which has a line-of-sight penetration through the igloo and test cell wall. All current options for maintenance of the injector require personnel access. A nuclear analysis has been performed to determine the feasibility of hands-on access. Results indicate that personnel access to the pellet injector glovebox is possible. 10 refs., 3 figs., 3 tabs.

  10. Design of a repeating pneumatic pellet injector for the Joint European Torus

    International Nuclear Information System (INIS)

    Milora, S.L.; Combs, S.K.; Baylor, L.R.; Sparks, D.O.; Foust, C.R.; Gethers, F.E.

    1987-01-01

    A three-barrel pneumatic pellet injector has been developed for plasma fueling of the Joint European Torus (JET). The versatile device consists of three independent machine-gun-like mechanisms that operate at cryogenic temperatures (14 0 K to 20 0 K). Individual high speed extruders provide a continuous supply of solid deuterium to each gun assembly, where a reciprocating breech-side cutting mechanism forms and chambers cylindrical pellets from the extrusion; deuterium pellets are then accelerated in the gun barrels with controlled amounts of compressed hydrogen gas (pressures up to 100 bars) to velocities ≤ 1.5 km/s. The injector features three nominal pellet sizes (2.7 mm, 4.0 mm, and 6.0 mm) and has been tested at repetition rates of 5 Hz, 2.5 Hz, and 1 Hz, respectively. Each gun is capable of operating (individually or simultaneously) at the design repetition rate for 15-second duration pulses (limited only by the capacity of the extruder feed system). A remote, stand-alone control and data acquisition system is used for injector operation. 7 refs

  11. A high-power millimeter wave driven steam gun for pellet injectors

    International Nuclear Information System (INIS)

    Itoh, Yasuyuki

    1997-01-01

    A concept of steam gun is proposed for using in two-stage pneumatic hydrogen isotope pellet injectors. The steam gun is driven by megawatt-level high-power millimeter waves (∼100 GHz) supplied by gyrotrons. A small amount of water is injected into its pump tube. The water is instantaneously heated by the millimeter waves and vaporized. Generated high-pressure steam accelerates a piston for compressing light gas to drive a frozen pellet. Discussions in this paper concentrate on the piston acceleration. Results show that 1 MW millimeter waves accelerate the 25 g piston to velocities of ∼200 m/s in a 1 m-long pump tube. The piston acceleration characteristics are not improved in comparison to light gas guns with first valves. The steam gun concept, however, avoids the use of a large amount of high-pressure gas for piston accelerations. In future fusion reactors, gyrotrons used during preionization and start-up phase would be available for producing required millimeter waves. (author)

  12. Development of a precise size-controllable pellet injector for the detailed studies of ablation phenomena and mechanism

    International Nuclear Information System (INIS)

    Ichizono, K.; Kugimiya, S.; Nourgostar, S.; Sato, K.N.

    2004-01-01

    A pellet injector of new type with accurately and continuously controllable system of pellet size has started to be developed. This has a unique mechanics and structure of producing a frozen pellet in extremely low temperature region. In the device presently developed in this research, we will precisely adjust the length of the cylindrical pellet (diameter 1.0 mm) from 0.5 to 3 mm by using the special 'length limiting rod' system

  13. Design of a repeating pneumatic pellet injector for the Joint European Torus

    International Nuclear Information System (INIS)

    Milora, S.L.; Combs, S.K.; Baylor, L.R.; Foust, C.R.; Gethers, F.E.; Sparks, D.O.

    1987-01-01

    A three-barrel pneumatic pellet launcher developed at Oak Ridge National Laboratory (ORNL) serves as the principal component of a plasma fueling system for the Joint European Torus (JET). The versatile device consists of three independent machine gun-like mechanisms that operate at cryogenic temperatures (14-20K). Individual high-speed extruders provide a continuous supply of solid deuterium to each gun assembly, where a reciprocating breech-side cutting mechanism forms and chambers cylindrical pellets from the extrusion; the deuterium pellets are then accelerated in the gun barrels with controlled amounts of compressed hydrogen gas (pressures up to 100 bar) to velocities of ≤1.5 km/s. The injector features three nominal pellet sizes (2.7,4.0, and 6.0 mm) and has been tested at pellet repetition rates of 5,2.5, and 1 Hz, respectively. Each gun can operate (individually or simultaneously) at the design repetition rate for 15-s pulses (limited only by the capacity of the extruder feed system). A remote, stand-alone control and data acquisition system is used for injector operation

  14. Laser-prearc railgun: Development for the application to a fuel pellet injector of a nuclear fusion reactor

    Science.gov (United States)

    Tamura, H.; Sawaoka, A. B.; Oda, Y.; Onozuka, M.; Kuribayashi, S.; Shimizu, K.

    1992-05-01

    The laser-prearc railgun, that utilizes the phenomenon of laser-induced arc formation, was constructed and tested with plastic pellet projectiles. We envision our railgun as especially well suited as a solid hydrogen pellet injector for magnetic confinement fusion. The system consisted of a gas gun for preacceleration of a pellet and a railgun for its primary acceleration. A Q-switched ruby laser was used to induce electrical breakdown of propellant helium gas behind a dielectric pellet in the railgun. The present railgun was shown to accelerate a plastic pellet up to a velocity of 2.4 km/s.

  15. Radiation analysis of the CIT [Compact Ignition Tokamak] pellet injector system and its impact on personnel access

    International Nuclear Information System (INIS)

    Selcow, E.C.; Stevens, P.N.; Gomes, I.C.; Gomes, L.M.

    1988-08-01

    The conceptual design of the Compact Ignition Tokamak (CIT) is nearing completion. The CIT is a short-pulse ignition experiment, which is planned to follow the operations of the Tokamak Fusion Test Reactor (TFTR) at the Princeton Plasma Physics Laboratory (PPPL). The high neutron wall loadings, 4--5 MW/m 2 , associated with the operation of this device require that neutronics-related issues be considered in the overall system design. Radiation shielding is required for the protection of device components as well as personnel. A close-in igloo shield has been designed around the periphery of the tokamak structure, and the entire experiment is housed in a circular test cell facility that has a radius of 12 m. The most critical radiation concerns in the CIT design process relate to the numerous penetrations in the device. This report discusses the impact of a major penetration on the design and operation of the pellet injection system in the CIT. The pellet injector is a major component, and it has a line-of-sight penetration through the igloo and test cell wall. All current options for maintenance of the injector require hands-on-access. A nuclear analysis has been performed to establish the feasibility of hands-on-access. A coupled Monte Carlo/discrete-ordinates methodology was used to perform the analysis. This problem is characterized by deep penetration and streaming with very large length-to-diameter ratios. Results from this study indicate that personnel access to the pellet injector glovebox is possible. 14 refs., 3 figs., 3 tabs

  16. Results on Fermilab main injector dipole measurements

    International Nuclear Information System (INIS)

    Brown, B.C.; Baiod, R.; DiMarco, J.; Glass, H.D.; Harding, D.J.; Martin, P.S.; Mishra, S.; Mokhtarani, A.; Orris, D.F.; russell, O.A.; Tompkins, J.C.; Walbridge, D.G.C.

    1995-06-01

    Measurements of the Productions run of Fermilab Main Injector Dipole magnets is underway. Redundant strength measurements provide a set of data which one can fit to mechanical and magnetic properties of the assembly. Plots of the field contribution from the steel supplement the usual plots of transfer function (B/I) vs. I in providing insight into the measured results

  17. A two-stage pneumatic repeating pellet injector for refueling magnetically confined plasmas in long-pulse fusion experiments

    International Nuclear Information System (INIS)

    Frattolillo, A.; Migliori, S.; Scaramuzzi, F.; Capobianchi, M.; Domma, C.; Ronci, G.

    1995-01-01

    An experiment to demonstrate the feasibility of a repetitive pneumatic pellet injector at 1 Hz in the velocity range of 2 to 3 knVs was carried out in a collaboration between Oak Ridge National Laboratory and ENEA Frascati, in the context of a cooperative agreement between the US Department of Energy and EURATOM-ENEA Association. The third round of this experiment was completed in May 1995. Both the operation and performance of the equipment were improved, and the original objectives of the collaboration have been met. The facility was also briefly operated with neon pellets to explore the potential for producing fast ''killer'' pellets for disruption amelioration applications. Speeds of 1.7 km/s were achieved using a piston mass of 43 g. Higher speeds should be achievable with a system specifically designed for neon or other higher Z gases. Finally, tests were performed with thin boron carbide coatings (2 μm) on the Ergal pistons. The test results were encouraging because piston friction was reduced was the piston wear

  18. Improvements in a tracer - encapsulated solid pellet and its injector for more advanced plasma diagnostics

    International Nuclear Information System (INIS)

    Tamura, Naoki; Suzuki, Chihiro; Funaba, Hisamichi; Hayashi, Hiromi; Maeno, Hiroya; Yokota, Mitsuhiro; Ogawa, Hideki; Sudo, Shigeru; Takagi, Masaru; Satoh, Nakahiro

    2015-01-01

    Although we are facing the age of the International Thermonuclear Experiment Reactor (ITER), many physics issues related to the confinement of magnetically-confined toroidal plasma still remain to be clarified. For example, under some conditions, impurities inside the magnetically-confined toroidal plasma tend to accumulate into the core region of the plasma. This will cause a dilution of fusion fuel. Moreover, a radiation loss from the core plasma will be enhanced due to the impurity accumulation, and then the temperature in the core region will be decreased dramatically. Consequently, fusion plasma performance will be degraded below the acceptable level. In order to develop strategy for obviating and suppressing the impurity accumulation, it is significantly important to gain a full understanding of the impurity transport in the magnetically-confined toroidal plasma. In consideration of such a situation, we have developed a Tracer-Encapsulated Solid Pellet (TESPEL) for promoting a precise study of the impurity transport. To put it plainly, the TESPEL is a double-layered impurity pellet. This form enables us to produce a both poloidally and toroidally localized 'tracer' impurity source in the plasma, and to specify the total amount of the tracer impurity deposited in the plasma precisely. In this contribution, we introduce new-type TESPELs, which are greatly improved in regard to the above-mentioned features. Owing to this improvement, we have achieved a shallower penetration of the TESPEL into the plasma with sufficient quantities of the tracer particles, which can be measured with the existing diagnostics. In addition, we also introduce a new TESPEL injector, which enables us to inject the TESPEL obliquely into the plasma. This injector can also contribute to a further shallower penetration of the TESPEL into the plasma. Moreover, we will discuss a future strategy of the TESPEL in the research of fusion plasma and plasma application. (author)

  19. Design and implementation of a control system for a deuterium pellet injector

    International Nuclear Information System (INIS)

    Burris, R.D.; Baylor, L.R.; Greenwood, D.E.; Stewart, K.A.

    1986-03-01

    The Oak Ridge National Laboratory is currently developing a Deuterium Pellet Injector for installation on the Tokamak Fusion Test Reactor (TFTR). This paper describes the design and development of a stand-alone data acquisition and control system for that device. Major elements of the hardware are an Allen-Bradley PLC 2/30 programmable logic controller, a MicroVAX-II computer using the VMS operating system, CAMAC data acquisition and communication equipment, and special-purpose controllers for temperature and for the sequencing of pellet firing valves. The PLC performs all actual control actions and acquires data pertinent to those actions. The MicroVAX receives the data acquired by the PLC, displays it for the operator, prompts for and processes requests for action from the operator, and informs the PLC of those requests. The primary purpose of this paper is to describe the software operating in the MicroVAX, including the system architecture, major tasks, and ancillary and background tasks

  20. Pellet injection in WVIIA

    International Nuclear Information System (INIS)

    Renner, H.; Wuersohing, E.; Weller, A.; Jaeckel, H.; Hartfuss, H.; Hacker, H.; Ringler, H.; Buechl, K.

    1986-01-01

    The results of pellet injection experiments in the Wendelstein VII A stellarator are presented. The injector was a single shot pneumatic gun using deuterium pellets. Experiments were carried out in both ECRH and NI plasmas. Data is shown for plasma density, energy confinement, penetration depth and pellet ablation. Results are compared to a neutral gas shielding model

  1. Results from recent hydrogen pellet acceleration studies with a 2-m railgun

    International Nuclear Information System (INIS)

    Kim, K.; Zhang, D.J.; King, T.; Haywood, R.; Manns, W.; Venneri, F.

    1989-12-01

    A new 3.2-mm-diameter, two-stage, fuseless, plasma-arc-driven electromagnetic railgun has been designed, constructed, and successfully operated to achieve a record velocity of 2.67 km/s( b ) for 3.2 mmD x 4 mmL solid hydrogen pellet. The first stage of this hydrogen pellet injector is a combination of a hydrogen pellet generator and a gas fun. The second stage is a 2-m-long railgun which serves as a booster accelerator. The gas fun accelerates a frozen hydrogen pellet to a medium velocity and injects it into the railgun through a perforated coupling piece, which also serves a pressure-relieving mechanism. An electrical breakdown of the propellant gas, which has followed the pellet from the gas fun into the railgun, forms a conducting plasma-arc armature immediately behind the pellet allowing for fuseless operation of the railgun. Study of the pressure profile and the behavior of the plasma-arc armature inside the railgun bore led to elimination of spurious arcing, which prevents operation of the railgun at high voltages (and, therefore, at high currents). A timing circuit that can automatically measure the pellet input velocity and allows for accurate control of arc initiation behind the pellet helps prevent pellet disintegration and mistriggering of the arc initiation circuit. Results from the recent cryogenic operation of the two-stage pellet acceleration system are reported. 11 refs., 2 figs., 1 tab

  2. Results of REIMEP '89 UO2 pellet

    International Nuclear Information System (INIS)

    Mayer, K.; Alonso, A.; Bievre, P. de; Lycke, W.; Bolle, W. de; Gallet, M.; Hendrickx, F.

    1991-01-01

    The interest in the safeguards of fissile material focuses on a limited number of compounds which play key roles in the nuclear fuel cycle. Amongst these materials Uranium Dioxide pellets are of considerable importance as they enter the reactors in order to generate energy. In LWR's pellets with an initial 235 U content of about 3 mass % are used, whereas natural or depleted material is applied for the breeding zone in FBR's. The 89/90 round o REIMEP covered Uranium materials with 235 U abundances in the range of natural or depleted material. UO 2 pellets were distributed to 21 laboratories for analysis. The participating laboratories were asked to determine the Uranium content and the isotopic composition of the material. The results reported by the participants are presented as graphs thus giving a picture of the state-of-the-practice

  3. High-speed repetitive pellet injector prototype for magnetic confinement fusion devices

    International Nuclear Information System (INIS)

    Frattolillo, A.; Gasparotto, M.; Migliori, S.; Angelone, G.; Baldarelli, M.; Scaramuzzi, F.; Ronci, G.; Reggiori, A.; Riva, G.; Carlevaro, R.; Daminelli, G.B.

    1992-01-01

    The design of a test facility aimed at demonstrating the feasibility of high-speed repetitive acceleration of solid D 2 pellets for fusion applications, developed in a collaboration between Oak Ridge National Laboratory and ENEA Frascati, is presented. The results of tests performed at the CNPM/CNR on the piston wear in a repetitively operating two-stage gun are also reported

  4. High-speed lithium pellet injector commissioning in ASDEX Upgrade to investigate impact of Li in an all-metal wall tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Arredondo Parra, Rodrigo; Lang, Peter Thomas; Ploeckl, Bernhard [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Cardella, Antonino [Technische Universitaet Muenchen, Garching (Germany); Fusion for Energy, Garching (Germany); Macian Juan, Rafael [Technische Universitaet Muenchen, Garching (Germany); Neu, Rudolf [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Technische Universitaet Muenchen, Garching (Germany)

    2015-05-01

    Encouraging results with respect to plasma performance have been observed in several tokamak devices (TFTR, NSTX, etc) when injecting Lithium. Recently, a pedestal broadening resulting in an enhanced energy content during transient ELM-free H-mode phases was achieved in DIII-D. Experiments are planned at ASDEX Upgrade, aiming to investigate the impact of Li in an all-metal wall tokamak and to enhance the pedestal operational space. For this purpose, a Lithium pellet injector has been developed, capable of injecting pellets with a particle content up to 1.64 . 10{sup 20} atoms (1.89 mg) at a foreseen maximum repetition rate of 3 Hz. Free flight launch from the torus outboard side without a guiding tube is envisaged. A transfer efficiency exceeding 90 % was achieved in the test bed. Pellets will be accelerated in a gas gun; hence special care must be taken to avoid deleterious effects by the propellant gas pulse, this being the main plasma gas, leading to speeds ranging from 500 (m)/(s) to 800 (m)/(s). Additionally, a large expansion volume equipped with a cryopump is added in to the flight path. The injector is expected to commence operation by May 2015.

  5. PBX/TFTR pellet program PPPL

    International Nuclear Information System (INIS)

    Schmidt, G.

    1986-01-01

    Goals, current results and plans for pellet injection work for the PBX and TFTR programs are outlined. The present PBX injector is a prototype for ORNL 4 pellet condensing injectors. It has demonstrated that pellet injection on PBX can be used to increase overall density and alter the density profile. Future PBX operation requires reliable operation in deuterium and tritium, multiple pellet capability and ability to vary the size of pellets. These goals will require the construction of a new injector similar to the TFTR DPI system. It has also been demonstrated that pellets can efficiently fuel TFTR, producing a clean, high density plasma. Issues which are still outstanding include isotope exchange effects, use of different pellet sizes, optimization of pellet density perturbations and pellet penetration at high beam power

  6. The new centrifuge high-speed pellet injector for ASDEX Upgrade

    International Nuclear Information System (INIS)

    Lang, P.T.; Andelfinger, C.; Beck, W.; Buchelt, E.; Buechl, K.; Cierpka, P.; Kollotzek, H.; Lang, R.S.; Prausner, G.; Soeldner, F.X.; Ulrich, M.; Weber, G.

    1993-04-01

    We report on the new pellet injection system for refuelling the ASDEX Upgrade tokamak with cubic H 2 or D 2 pellets having alternative side lengths of 1.5, 1.75 and 2.0 mm and optional Ne doping. The system delivers series of about one hundred pellets at a maximum repetition rate of more than 40 Hz. The pellets are accelerated by means of a centrifuge with an optimized straight acceleration arm. This configuration minimizes the compulsive force acting on the pellet during the acceleration process. Since this also minimizes stresses inside the pellet, high velocities - a maximum of 1211 m/s being achieved - are possible without destroying the hydrogen cubes. A special pellet feed-in technique based on a static stop cylinder interrupting the acceleration path successfully reduced the horizontal scattering angle to values of less than ± 4 degrees. Thus, a high efficiency - with more than 90% of the pellets arriving within the acceptance angle - was achieved without using a guide tube. The whole system was found to work very reliably and reproducibly during the whole test operation period, covering about 10 5 pellet shots. The new centrifuge, now integrated into the ASDEX Upgrade setup, has proved to be a reliable unit even for long operation periods thus affording the possibility of quasicontinuous particle refuelling throughout a plasma discharge in ASDEX Upgrade. (orig.)

  7. Eight-shot pellet injector and fueling experiments at the HL-1M tokamak

    International Nuclear Information System (INIS)

    Xiao Zhenggui; Li Bo; Li Li

    2001-01-01

    An Eight-shot Pellet Injection (EPI) system has been proposed and developed in collaboration between STU (St. Petersburg State Technical University) of Russia and SWIP. In the EPI, the I n-situ c ondensation technique was used to produce the pellets in eight gun barrels respectively. The nominal pellet size (diameter of 1.0 mm and of 1.4 mm or 1.2 mm) is limited by the gun barrel inner diameter. The pellet length is adjusted by changing the g radient temperature o n the gun barrels and the amounts of filling fuel gas. Pellets are fired at speed range of 200 - 1200 m/s by He propellant with pressure of 2 - 6 MPa and then transferred to HL-1M vessel through an injection line that consists of two set of differential vacuum pumped chambers and guide tube combined with fast valves. In addition, this unit is equipped with diagnostics for pellet velocity and shape measure. The EPI has installed on HL-1M since 1996 for the multi-shot pellet fueling experiments. The typical characteristics including the peaked density profile and improved confinement, the deep penetration and suppression of soft X-ray sawteeth, the variance of rotation and flow of plasma in edge region as well as the photographing of pellet ablation clouds are presented

  8. The CIT [compact ignition tokamak] pellet injection system: Description and supporting research and development

    International Nuclear Information System (INIS)

    Gouge, M.J.; Combs, S.K.; Fisher, P.W.; Milora, S.L.

    1989-01-01

    The Compact Ignition Tokamak (CIT) will use an advance, high-velocity pellet injection system to achieve and maintain ignited plasmas. Two pellet injectors are provided: a moderate-velocity (1-to 1.5-km/s), single-stage pneumatic injector with high reliability and a high-velocity (4- to 5-km/s), two-stage pellet injector that uses frozen hydrogenic pellets encased in sabots. Both pellet injectors are qualified for operation with tritium feed gas. Issues such as performance, neutron activation of injector components, maintenance, design of the pellet injection vacuum line, gas loads to the reprocessing system, and equipment layout are discussed. Results and plans for supporting research and development (R and D) in the areas of tritium pellet fabrication and high-velocity, repetitive two-stage pneumatic injectors are presented. 7 refs., 4 figs., 2 tabs

  9. Results of hydrogen pellet injection into ISX-B

    International Nuclear Information System (INIS)

    Milora, S.L.; Foster, C.A.; Thomas, C.E.

    1980-09-01

    High speed pellet fueling experiments have been performed on the ISX-B device in a new regime characterized by large global density rise in both ohmic and neutral beam heated discharges. Hydrogen pellets of 1 mm in diameter were injected in the plasma midplane at velocities exceeding 1 km/s. In low temperature ohmic discharges, pellets penetrate beyond the magnetic axis, and in such cases a sharp decrease in ablation is observed as the pellet passes the plasma center. Density increases of approx. 300% have been observed without degrading plasma stability or confinement. Energy confinement time increases in agreement with the empirical scaling tau/sub E/ approx. n/sub e/ and central ion temperature increases as a result of improved ion-electron coupling. Laser-Thomson scattering and radiometer measurements indicate that the pellet interaction with the plasma is adiabatic. Penetration to r/a approx. 0.15 is optimal, in which case large amplitude sawtooth oscillations are observed and the density remains elevated. Gross plasma stability is dependent roughly on the amount of pellet penetration and can be correlated with the expected temporal evolution of the current density profile

  10. Pellets for fusion reactor refueling. Annual progress report, 1 January 1975--31 December 1975

    International Nuclear Information System (INIS)

    Turnbull, R.J.

    1976-01-01

    The feasibility of refueling fusion reactors using pellets of deuterium-tritium is discussed. A pellet injector has been constructed and experiments have been done injecting solid pellets into the ORMAK machine. Theoretical explanations of the results from these experiments have been successful. Other experiments underway include techniques for charging the pellets in order to accelerate and control them

  11. Results obtained using the pellet charge exchange diagnostic on TFTR

    International Nuclear Information System (INIS)

    McChesney, J.M.; Fisher, R.K.; Parks, P.B.; Duong, H.H.; Mansfield, D.K.; Medley, S.S.; Roquemore, A.L.; Petrov, M.P.

    1994-05-01

    Experiments are underway on TFTR to measure the confined alpha particle distribution functions using small low-Z pellets injected into the plasma. Upon entering the plasma, the pellet ablates, forming a plasma ablation cloud, elongated in the magnetic field direction, that travels alongside the pellet. A small fraction of the fusion produced 3.5 MeV alpha particles incident on the cloud are converted to helium neutrals. By measuring the resultant helium neutrals escaping from the plasma by means of a mass and energy resolving charge exchange analyzer, the energy distribution of the alpha particles incident on the cloud can be inferred. Preliminary experiments to observe neutrals from the 100-1000 keV He tail produced during ICRF minority heating experiments were successful. However, no significant alpha particle signals have been observed during D-T operation on TFTR. The authors attribute this lack of signal to stochastic toroidal field ripple loss in the outer regions of the plasma. They are studying ways to improve the pellet penetration so that the pellet penetrates into the central regions of the plasma where ripple induced losses are small and the alpha population is high

  12. Deterioration of the fuel injection parameters as a result of Common Rail injectors deposit formation

    Directory of Open Access Journals (Sweden)

    Stępień Zbigniew

    2017-01-01

    Full Text Available The article describes external and internal Common Rail injectors deposits formed in dynamometer engine simulation tests. It discussed not only the key reasons and factors influencing injector deposit formation but also the resulting way of fuel preparation and engine test approaches. The effects of external coking deposit as well as internal deposits two most common form types that is carboxylic soaps and organic amides on deterioration of the fuel injection parameters were assessed. The assessments covered both deposits impacts on quantitative and qualitative changes of the injectors diagnostic parameters and as a result on deterioration of the injector performance. Finally the comparisons between characteristic of dosage of one fuel injector before test and characteristics few injectors after engine tests of simulated deposit formation were made.

  13. A four-pellet pneumatic injection system in the JT-60

    International Nuclear Information System (INIS)

    Hiratsuka, Hajime; Kawasaki, Kouzo; Miyo, Yasuhiko; Yoshioka, Yuji; Ohta, Kazuya; Shimizu, Masatsugu; Kondo, Ikuo; Onozuka, Masanori; Shimomura, Tomoyoshi; Iwamoto, Syuichi; Hashiri, Noboru

    1991-01-01

    A four-pellet pneumatic injection system has been developed for plasma fueling of the JT-60. The JT-60 pellet injector is capable of accelerating separately four cylindrical pellets 3.0 mm in diameter x 3.0 mm long for two pellets and 4.0 mm in diameter x 4.0 mm long for the remaining two. The JT-60 pellet injector was installed on the JT-60 tokamak machine at the end of 1988. Obtained pellet velocity was higher than 2300 m/s by propellant gases of up to 100 bar and the pellet fueling efficiency achieved was around 70% for both dimensions of pellets. This paper describes the design, injection operation and performance test results of the JT-60 pellet injector. (orig.)

  14. A four-pellet pneumatic injection system in the JT-60

    Energy Technology Data Exchange (ETDEWEB)

    Hiratsuka, Hajime; Kawasaki, Kouzo; Miyo, Yasuhiko; Yoshioka, Yuji; Ohta, Kazuya; Shimizu, Masatsugu; Kondo, Ikuo (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan)); Onozuka, Masanori; Shimomura, Tomoyoshi; Iwamoto, Syuichi; Hashiri, Noboru (Mitsubishi Heavy Industries Ltd., Kobe (Japan))

    1991-05-01

    A four-pellet pneumatic injection system has been developed for plasma fueling of the JT-60. The JT-60 pellet injector is capable of accelerating separately four cylindrical pellets 3.0 mm in diameter x 3.0 mm long for two pellets and 4.0 mm in diameter x 4.0 mm long for the remaining two. The JT-60 pellet injector was installed on the JT-60 tokamak machine at the end of 1988. Obtained pellet velocity was higher than 2300 m/s by propellant gases of up to 100 bar and the pellet fueling efficiency achieved was around 70% for both dimensions of pellets. This paper describes the design, injection operation and performance test results of the JT-60 pellet injector. (orig.).

  15. IAEA technical committee meeting on pellet injection

    International Nuclear Information System (INIS)

    1993-01-01

    The IAEA Technical Committee Meeting on Pellet Injection, May 10-12, 1993, at the Japan Atomic Energy Research Institute, Naka, Ibaraki-ken, Japan, was held to review the latest results on pellet injection and its effects on plasma confinement. In particular, topics included in the meeting include (i) pellet ablation and particle fueling results, (ii) pellet injection effects on confinement, including improved confinement modes, edge effects, magnetohydrodynamic activity and impurity transport, and (iii) injector technology and diagnostics using pellets. About 30 experts attended and 23 papers were presented. Refs, figs and tabs

  16. Initial deuterium pellet experiments on FTU

    International Nuclear Information System (INIS)

    Snipes, J.A.

    1993-01-01

    Initial experiments have been performed with the Single Pellet INjector (SPIN) on FTU. SPIN is a two-stage cryogenic deuterium pellet injector capable of injection,a pellets with velocities up to 2.5 km/s. The nominal pellet mass for these experiments was approximately 1 x 10 20 atoms. These initial pellet experiments concentrated on studying pellet penetration under a variety of plasma conditions to compare with code predictions and to examine toroidal particle transport. The principal diagnostics used were two fast (∼1 μsec) photomultiplier tubes at nearly opposite toroidal locations with H α (D α ) interference filters (λ = 656 nm), a microwave cavity for pellet mass and velocity, a vertical array of soft x ray diodes without filters looking down onto the pellet, a DCN interferometer for electron density profiles, and a Michelson ECE system for electron temperature profiles. The time integral of the absolutely calibrated fast H α signal appears to give reasonable agreement with the expected pellet mass. Toroidal transport of deuterium ions from the pellet to nearly the opposite side of the tokamak agrees with calculated thermal deuterium velocities near the plasma edge. Comparison of the experimental results with code calculations using the Neutral Gas Shielding model show good agreement for the post-pellet electron temperature and density profiles and the H α profiles in some cases. Calculated penetration distances agree within 20%

  17. Interaction between a high density-low temperature plasma and a frozen hydrogen pellet in a railgun injector

    International Nuclear Information System (INIS)

    Grapperhaus, M.J.

    1993-01-01

    A model has been developed which describes the ablation process of frozen hydrogen pellets in an electromagnetic railgun. The model incorporates the neutral gas shielding model in which the pellet surface is heated by incident electrons from the plasma arc. The heated surface then ablates, forming a neutral cloud which attenuates the incoming electrons. The energy lost in the cloud by the electrons heats the ablatant material as it flows into the plasma arc. Under steady-state conditions, a scaling law for the ablation rate was derived as a function of plasma-arc temperature and density. In addition, flow conditions and the criteria for the existence of a steady-state solution were formulated and subsequently examined under simplifying assumptions. Comparison with experimentally observed ablation rates shows good qualitative agreement

  18. A single-stage high pressure steam injector for next generation reactors: test results and analysis

    International Nuclear Information System (INIS)

    Cattadori, G.; Galbiati, L.; Mazzocchi, L.; Vanini, P.

    1995-01-01

    Steam injectors can be used in advanced light water reactors (ALWRs) for high pressure makeup water supply; this solution seems to be very attractive because of the ''passive'' features of steam injectors, that would take advantage of the available energy from primary steam without the introduction of any rotating machinery. The reference application considered in this work is a high pressure safety injection system for a BWR; a water flow rate of about 60 kg/s to be delivered against primary pressures covering a quite wide range up to 9 MPa is required. Nevertheless, steam driven water injectors with similar characteristics could be used to satisfy the high pressure core coolant makeup requirements of next generation PWRs. With regard to BWR application, an instrumented steam injector prototype with a flow rate scaling factor of about 1:6 has been built and tested. The tested steam injector operates at a constant inlet water pressure (about 0.2 MPa) and inlet water temperature ranging from 15 to 37 o C, with steam pressure ranging from 2.5 to 8.7 MPa, always fulfilling the discharge pressure target (10% higher than steam pressure). To achieve these results an original double-overflow flow rate-control/startup system has been developed. (Author)

  19. Comparison of pellet acceleration model results to experimentally observed penetration depths

    Energy Technology Data Exchange (ETDEWEB)

    Szepesi, T., E-mail: szepesi.tamas@gmail.co [KFKI - Research Institute for Particle and Nuclear Physics, EURATOM Association, MTA KFKI-RMKI, P.O. Box 49, H-1525 Budapest-114 (Hungary); Kalvin, S.; Kocsis, G. [KFKI - Research Institute for Particle and Nuclear Physics, EURATOM Association, MTA KFKI-RMKI, P.O. Box 49, H-1525 Budapest-114 (Hungary); Lang, P.T. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany); Senichenkov, I. [Saint Petersburg State Polytechnical University, Polytehnicheskaya 29, 195251 St. Petersburg (Russian Federation)

    2009-06-15

    Cryogenic hydrogen isotope fuelling pellets were observed to undergo strong radial acceleration in the confined plasma. The reason for pellet acceleration is believed to originate from drift effects: the ionised part of pellet cloud is affected by the grad-B drift, therefore, the cloud becomes polarised. The E x B drift then deforms the pellet cloud so that it can no longer follow the original flux bundle - this results in a less efficient shielding on the pellet's HFS region, where the subsequently enhanced ablation pushes the pellet towards LFS, like a rocket. In order to study this effect, a simple and a comprehensive ablation model was developed. Results from both models show quantitatively acceptable agreement with ASDEX-Upgrade experiments concerning trajectory curvature, corresponding to radial acceleration in the range of 10{sup 4}-10{sup 7} m/s{sup 2}.

  20. Second jet workshop on pellet injection: pellet fueling program in the United States. Summary

    International Nuclear Information System (INIS)

    Milora, S.L.

    1983-01-01

    S. Milora described the US programme on pellet injection. It has four parts: (1) a confinement experimental program; (2) pellet injector development; (3) theoretical support; and (4) tritium pellet study for TFTR

  1. Proposed high speed pellet injection system 'HIPEL' for Large Helical Device

    International Nuclear Information System (INIS)

    Sudo, S.; Kanno, M.; Kaneko, H.; Saka, S.; Shirai, T.; Baba, T.

    1993-11-01

    From the results of the simulation study including pellet ablation and 1-D transport code, it is found that a high speed pellet injector with pellet velocity of more than 3 km/s is necessary for the penetration of the pellet with diameter of 3 mm into the core region under the expected plasma condition of Large Helical Device (LHD) of heliotron/stellarator type with superconducting coils at NIFS in Japan. Therefore, a two stage pellet injector was constructed and tested successfully in order to obtain the pellet velocity range of 3 km/s. Based upon the above results, a high speed flexible multiple-pellet injection system 'HIPEL' for LHD is proposed. HIPEL consists of independent (1) 10 two-stage gun barrels and (2) 10 single-stage gun barrels. It has multi purposes such as refueling and flexible density profile control, diagnostics and the other functions. (author)

  2. Performance characterization of pneumatic single pellet injection system

    International Nuclear Information System (INIS)

    Schuresko, D.D.; Milora, S.L.; Hogan, J.T.; Foster, C.A.; Combs, S.K.

    1983-01-01

    The Oak Ridge National Laboratory single-shot pellet injector, which has been used in plasma fueling experiments on ISX and PDX, has been upgraded and extensively instrumented in order to study the gas dyamics of pneumatic pellet injection. An improved pellet transport line was developed which utilizes a 0.3-cm-diam by 100-cm-long guide tube. Pellet gun performance was characterized by measurements of breech and muzzle dynamic pressures and by pellet velocity and mass determinations. Velocities of up to 1.4 km/s were achieved for intact hydrogen pellets using hydrogen propellant at 5-MPa breech pressure. These data have been compared with new pellet acceleration calculations which include the effects of propellant friction, heat transfer, time-dependent boundary conditions, and finite gun geometry. These results provide a basis for the extrapolation of present-day pneumatic injection system performance to velocities in excess of 2 km/s

  3. Performance characterization of pneumatic single pellet injection system

    International Nuclear Information System (INIS)

    Schuresko, D.D.; Milora, S.L.; Hogan, J.T.; Foster, C.A.; Combs, S.K.

    1982-01-01

    The Oak Ridge National Laboratory single-shot pellet injector, which has been used in plasma fueling experiments on ISX and PDX, has been upgraded and extensively instrumented in order to study the gas dynamics of pneumatic pellet injection. An improved pellet transport line was developed which utilizes a 0.3-cm-diam by 100-cm-long guide tube. Pellet gun performance was characterized by measurements of breech and muzzle dynamic pressures and by pellet velocity and mass determinations. Velocities up to 1.4 km/s were achieved for intact hydrogen pellets using hydrogen propellant at 5-MPa breech pressure. These data have been compared with new pellet acceleration calculations which include the effects of propellant friction, heat transfer, time-dependent boundary conditions, and finite gun geometry. These results provide a basis for the extrapolation of present-day pneumatic injection system performance to velocities in excess of 2 km/s

  4. Performance test results of ion beam transport for SST-1 neutral beam injector

    Energy Technology Data Exchange (ETDEWEB)

    Jana, M R; Mattoo, S K [Institute for Plasma Research Bhat, Gandhinagar-382428, Gujarat (India); Uhlemann, R, E-mail: mukti@ipr.res.i [Forschungszentrum Juelich, Institute fur Energieforschung IEF-4, Plasmaphysik D-52425 Juelich (Germany)

    2010-02-01

    A neutral beam injector is built at IPR to heat the plasma of SST-1 and its upgrade. It delivers a maximum beam power of 1.7 MW for 55 kV Hydrogen beam or 80 kV Deuterium beam. At lower beam voltage, the delivered power falls to 500 kW at 30 kV Hydrogen beam which is adequate to heat SST-1 plasma ions to {approx} 1 keV. Process of acceleration of ions to the required beam voltage, conversion of ions to neutrals and removal of un-neutralized ions and the beam diagnostic systems occupy a large space. The consequence is that linear extent of the neutral beam injector is at least a few meters. Also, port access provides a very narrow duct. Even a very good injector design and fabrication practices keep beam divergence at a very low but finite value. The result is beam transport becomes an important issue. Since a wide area beam is constructed by hundreds of beam lets, it becomes essential they be focused in such a way that beam transport loss is minimized. Horizontal and vertical focal lengths are two parameters, in addition to beam divergence, which give a description of the beam transport. We have obtained these two parameters for our injector by using beam transport code; making several hundred simulation runs by varying optical parameters of the beam. The selected parameters set has been translated into the engineering features of the extractor grid set of the ion source. Aperture displacement technique is used to secure the horizontal beam focusing at 5.4 m. Combination of both aperture displacement and inclining of two grid halves to {approx} 17 mrad are secured for vertical beam focusing at 7 m from earth grid of the ion source. The gaps between the design, engineered and performance tested values usually arise due to lack of exercising control over fabrication processes or due to inaccuracies in the assumption made in the model calculations of beam optics and beam transport. This has been the case with several injectors, notably with JET injector. To overcome

  5. Occupational exposure of aldehydes resulting from the storage of wood pellets.

    Science.gov (United States)

    Rahman, Mohammad Arifur; Rossner, Alan; Hopke, Philip K

    2017-06-01

    An exposure assessment was conducted to investigate the potential for harmful concentrations of airborne short chain aldehydes emitted from recently stored wood pellets. Wood pellets can emit a number of airborne aldehydes include acetaldehyde, formaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and hexanal. Exposure limits have been set for these compounds since they can result in significant irritation of the upper respiratory system at elevated concentrations. Formaldehyde is a recognized human carcinogen and acetaldehyde is an animal carcinogen. Thus, air sampling was performed in a wood pellet warehouse at a pellet mill, two residential homes with bulk wood pellet storage bins, and in controlled laboratory experiments to evaluate the risk to occupants. Using NIOSH method 2539, sampling was conducted in five locations in the warehouse from April-June 2016 when it contained varying quantities of bagged pellets as well as two homes with ten ton bulk storage bins. The aldehyde concentrations were found to increase with the amount of stored pellets. Airborne concentrations of formaldehyde were as high as 0.45 ppm in the warehouse exceeding the NIOSH REL-C, and ACGIH TLV-C occupational exposure limits (OELs). The concentrations of aldehydes measured in the residential bins were also elevated indicating emissions may raise indoor air quality concerns for occupants. While individual exposures are of concern the combined irritant effect of all the aldehydes is a further raise the concerns for building occupants. To minimize exposure and the risk of adverse health effects to a building's occupants in storage areas with large quantities of pellets, adequate ventilation must be designed into storage areas.

  6. Study liquid length penetration results obtained with a direct acting piezo electric injector

    International Nuclear Information System (INIS)

    Payri, Raul; Gimeno, Jaime; Bardi, Michele; Plazas, Alejandro H.

    2013-01-01

    Highlights: ► A direct acting injector capable of controlling needle lift has been used to determine liquid phase penetration. ► The influence of injection pressure, chamber density and chamber temperature have been measured. ► When needle lift is reduced the stabilized liquid length is shortened. ► The relationship between needle lift and liquid length makes needle lift as a new way to control the injection event. - Abstract: A state of the art prototype common rail injector featuring direct control of the needle by means of a piezo stack (direct acting) has been tested. Liquid phase penetration of the sprays in diesel engine-like conditions has been studied via imaging technique in a novel continuous flow test chamber that allows an accurate control on a wide range of thermodynamic conditions (up to 1000 K and 15 MPa). This state of the art injector fitted with a 7-hole nozzle, allows a fully flexible control on the nozzle needle movement, enabling various fuel injection rate typologies. The temporal evolution of the seven sprays has been studied recording movies of the injection event in evaporative conditions via Mie scattering imaging technique and using a high speed camera. The results showed a strong influence of needle position on the stabilized liquid length while the effect of the injection pressure is negligible: the decrease of the needle lift causes a pressure drop in the needle seat and thus a reduction in the effective pressure upstream of the orifices (in the nozzle sac). According to known literature the stabilized liquid-length depends mainly on effective diameter, spray cone-angle and fuel/air properties and does not depend on fuel velocity at the orifice outlet. Therefore, due to small change in the spray cone-angle, higher injection pressures give slightly lower liquid length. However, partial needle lifts has an opposite effect: when needle is partially lifted a dramatic increase of the spray cone-angle and a consequent reduction of

  7. Pellet fueling development at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Foster, C.A.; Milora, S.L.; Schuresko, D.D.; Combs, S.K.; Lunsford, R.V.

    1982-01-01

    A pellet injector development program has been under way at the Oak Ridge National Laboratory (ORNL) since 1976 with the goals of developing D 2 , T 2 pellet fuel injectors capable of reliable repetitive fueling of reactors and of continued experimentation on contemporary plasma devices. The development has focused primarily on two types of injectors that show promise. One of these injectors is the centrifuge-type injector, which accelerates pellets in a high speed rotating track. The other is the gas or pneumatic gun, which accelerates pellets in a gun barrel using compressed helium of H 2 gas

  8. Application of the results of carbon pellet modeling to the problem of plasma penetration

    International Nuclear Information System (INIS)

    Vahala, L.L.; El Cashlan, A.G.; Gerdin, G.A.; Parks, P.B.

    1990-01-01

    The assumptions of the evaporation model for low-Z pellets interacting with magnetic fusion plasmas developed by P. B. Parks are tested. These assumptions are that the vapor density profile in the region adjacent to the pellet surface, falls off with radial distance as r -α , where 5 zi , is much less than a flow time for the vapor in this same region τ f (i.e. for r zi much-lt τ f , is tested at the sonic radius using the results from atomic physics and the low-Z evaporation model. It is found that indeed τ zi much-lt τ f for plasmas with parameters close to thermonuclear conditions (e.g. TFTR and CIT), but not for those of smaller Tokamaks such as TEXT. The results of pellet penetration calculations for the conditions of the TEXT carbon-pellet injection experiments are presented which show better agreement with experiment if the shielding fraction is calculated at each step of the pellet-penetration calculation, the effect of ionization is ignored, and if the effect of possible uncertainties in the background plasma parameters is included. 14 refs., 3 figs., 3 tabs

  9. Preliminary results of the International Fusion Materials Irradiation Facility deuteron injector

    Energy Technology Data Exchange (ETDEWEB)

    Gobin, R.; Adroit, G.; Bogard, D.; Bourdelle, G.; Chauvin, N.; Delferriere, O.; Gauthier, Y.; Girardot, P.; Guiho, P.; Harrault, F.; Jannin, J. L.; Loiseau, D.; Mattei, P.; Roger, A.; Sauce, Y.; Senee, F.; Vacher, T. [Commissariat a l' Energie Atomique et aux Energie Alternatives, CEA/Saclay, DSM/IRFU, 91191-Gif/Yvette (France)

    2012-02-15

    In the framework of the IFMIF-EVEDA project (International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities), CEA/IRFU is in charge of the design, construction, and characterization of the 140 mA continuous deuteron injector, including the source and the low energy beam line. The electron cyclotron resonance ion source which operates at 2.45 GHz is associated with a 4-electrode extraction system in order to minimize beam divergence at the source exit. Krypton gas injection is foreseen in the 2-solenoid low energy beam line. Such Kr injection will allow reaching a high level of space charge compensation in order to improve the beam matching at the radio frequency quadrupole (RFQ) entrance. The injector construction is now completed on the Saclay site and the first plasma and beam production has been produced in May 2011. This installation will be tested with proton and deuteron beams either in pulsed or continuous mode at Saclay before shipping to Japan. In this paper, after a brief description of the installation, the preliminary results obtained with hydrogen gas injection into the plasma chamber will be reported.

  10. Commissioning and First Results of the Electron Beam Profiler in the Main Injector at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Thurman-Keup, R. [Fermilab; Alvarez, M. [Fermilab; Fitzgerald, J. [Fermilab; Lundberg, C. [Fermilab; Prieto, P. [Fermilab; Zagel, J. [Fermilab; Blokland, W. [Oak Ridge

    2017-08-01

    The planned neutrino program at Fermilab requires large proton beam intensities in excess of 2 MW. Measuring the transverse profiles of these high intensity beams is challenging and often depends on non-invasive techniques. One such technique involves measuring the deflection of a probe beam of electrons with a trajectory perpendicular to the proton beam. A device such as this is already in use at the Spallation Neutron Source at ORNL and a similar device has been installed in the Main Injector at Fermilab. Commissioning of the device is in progress with the goal of having it operational by the end of the year. The status of the commissioning and initial results will be presented

  11. Multi-pellet injection on Jet

    International Nuclear Information System (INIS)

    Kupschus, P.; Cheetham, A.; Denne, B.; Gadeberg, M.; Gowers, C.; Gondhalekar, A.; Tubbing, B.; Schissel, D.

    1989-01-01

    The investigations carried out with the JET multi-pellet injector are presented. The results show that with central deposition, peaked density profiles with central values exceeding 10 20 /m 3 can be reached. These peaked profiles can persist for times of the order of seconds. Auxiliary heating seems to accelerate the slow central density decay; it is also observed that high electron pressure values are generated in a core with a high D-D reaction rate

  12. Outgassing measurements and results used in designing the Doublet III Neutral Beam Injector System

    International Nuclear Information System (INIS)

    Yamamoto, R.M.; Harvey, J.

    1979-11-01

    Material vacuum properties played an important part in designing the Neutral Beam Injector System for General Atomic's Doublet III Tokamak. Low operating vacuum tank pressures were desired to keep re-ionization of the Neutral Beam to a minimum. Plasma contamination was also a major concern, hence stringent material impurity constraints were imposed. Outgassing Rate Measurement and Residual Gas Analyses were performed on different types of materials to determine if their vacuum properties were compatible with the Neutral Beam Injector System requirements

  13. Experimental results on pellet injection and MHD from the RTP tokamak

    International Nuclear Information System (INIS)

    Oomens, A.A.M.; Kloe, J. de; Salzedas, F.J.B.

    2001-01-01

    The ablation of hydrogen pellets has been studied in the Rijnhuizen Tokamak Project RTP with a diagnostic with high spatial and temporal resolution. It has been observed that (part of the) ablation cloud drifts away from the pellet in opposite direction. These drifts occur in semi-periodical bursts. A summary of a detailed analysis of this drift of the cloud and its implications for the fueling profile is presented. Stabilization of m/n=2/1 tearing modes preceding density limit disruptions, has been studied with modulated and continuous ECRH. The results indicate that EC heating of the islands under these conditions is very inefficient. The time dependence of the growth rate of the precursor mode is first algebraic, but becomes exponential in a later phase. (author)

  14. Resonant Frequency Control For the PIP-II Injector Test RFQ: Control Framework and Initial Results

    Energy Technology Data Exchange (ETDEWEB)

    Edelen, A. L. [Colorado State U.; Biedron, S. G.; Milton, S. V.; Bowring, D.; Chase, B. E.; Edelen, J. P.; Nicklaus, D.; Steimel, J.

    2016-12-16

    For the PIP-II Injector Test (PI-Test) at Fermilab, a four-vane radio frequency quadrupole (RFQ) is designed to accelerate a 30-keV, 1-mA to 10-mA, H- beam to 2.1 MeV under both pulsed and continuous wave (CW) RF operation. The available headroom of the RF amplifiers limits the maximum allowable detuning to 3 kHz, and the detuning is controlled entirely via thermal regulation. Fine control over the detuning, minimal manual intervention, and fast trip recovery is desired. In addition, having active control over both the walls and vanes provides a wider tuning range. For this, we intend to use model predictive control (MPC). To facilitate these objectives, we developed a dedicated control framework that handles higher-level system decisions as well as executes control calculations. It is written in Python in a modular fashion for easy adjustments, readability, and portability. Here we describe the framework and present the first control results for the PI-Test RFQ under pulsed and CW operation.

  15. Comparison of cryogenic (hydrogen) and TESPEL (polystyrene) pellet particle deposition in a magnetically confined plasma

    Science.gov (United States)

    McCarthy, K. J.; Tamura, N.; Combs, S. K.; Panadero, N.; Ascabíbar, E.; Estrada, T.; García, R.; Hernández Sánchez, J.; López Fraguas, A.; Navarro, M.; Pastor, I.; Soleto, A.; TJ-II Team

    2017-10-01

    A cryogenic pellet injector (PI) and tracer encapsulated solid pellet (TESPEL) injector system has been operated in combination on the stellarator TJ-II. This unique arrangement has been created by piggy-backing a TESPEL injector onto the backend of a pipe-gun-type PI. The combined injector provides a powerful new tool for comparing ablation and penetration of polystyrene TESPEL pellets and solid hydrogen pellets, as well as for contrasting subsequent pellet particle deposition and plasma perturbation under analogous plasma conditions. For instance, a significantly larger increase in plasma line-averaged electron density, and electron content, is observed after a TESPEL pellet injection compared with an equivalent cryogenic pellet injection. Moreover, for these injections from the low-magnetic-field side of the plasma cross-section, TESPEL pellets deposit electrons deeper into the plasma core than cryogenic pellets. Finally, the physics behind these observations and possible implications for pellet injection studies are discussed.

  16. A redesigned follitropin alfa pen injector for infertility: results of a market research study

    Directory of Open Access Journals (Sweden)

    Abbotts C

    2011-06-01

    Full Text Available Carole Abbotts1, Cristiana Salgado-Braga2, Céline Audibert-Gros31Pharmaceutical Marketing Research Consultancy, London, UK; 2Fertility and Endocrinology Global Business Unit, 3Business Intelligence, Merck Serono SA, Geneva, SwitzerlandBackground: The purpose of this study was to evaluate patient-learning and nurse-teaching experiences when using a redesigned prefilled, ready-to-use follitropin alfa pen injector.Methods: Seventy-three UK women of reproductive age either administering daily treatment with self-injectable gonadotropins or about to start gonadotropin treatment for infertility (aged 24–47 years; 53 self-injection-experienced and 20 self-injection-naïve and 28 nurses from UK infertility clinics were recruited for the study. Following instruction, patients and nurses used the redesigned follitropin alfa pen to inject water into an orange and completed questionnaires to evaluate their experiences with the pen immediately after the simulated injections.Results: Most (88%, n = 64 patients found it easy to learn how to use the pen. Among injection-experienced patients, 66% (n = 35 agreed that the redesigned pen was easier to learn to use compared with their current method and 70% (n = 37 also said they would prefer its use over current devices for all injectable fertility medications. All nurses considered the redesigned pen easy to learn and believed it would be easy to teach patients how to use. Eighty-six percent (n = 24 of the nurses thought it was easy to teach patients to determine the remaining dose to be dialed and injected in a second pen if the initial dose was incomplete. Compared with other injection devices, 96% (n = 27 thought it was "much easier" to "as easy" to teach patients to use the redesigned pen. Based on ease of teaching, 68% (n = 19 of nurses would choose to teach the pen in preference to any other injection method. Almost all (93%, n = 26 nurses considered that having the same pen format for a range of

  17. Alpha diagnostics using pellet charge exchange: Results on TFTR and prospects for ITER

    International Nuclear Information System (INIS)

    Fisher, R.K.; Duong, H.H.; McChesney, J.M.

    1996-05-01

    Confinement of alpha particles is essential for fusion ignition and alpha physics studies are a major goal of the TFTR, JET, and ITER DT experiments, but alpha measurements remain one of the most challenging plasma diagnostic tasks. The Pellet Charge Exchange (PCX) diagnostic has successfully measured the radial density profile and energy distribution of fast (0.5 to 3.5 MeV) confined alpha particles in TFTR. This paper describes the diagnostic capabilities of PCX demonstrated on TFTR and discusses the prospects for applying this technique to ITER. Major issues on ITER include the pellet's perturbation to the plasma and obtaining satisfactory pellet penetration into the plasma

  18. Determination Of Simulated Pellet To Pellet Gap Using Neutron Radiography

    International Nuclear Information System (INIS)

    Kusnowo, A.

    1996-01-01

    The defect on the irradiated fuel element could be detected using neutron radiography. The defect could occurred in pellet to pellet gap, cladding, or even cladding to pellet gap. An investigations has been performed to detect pellet to pellet gap defect that might occur in an irradiated fuel element. An Al foil of 0,1; 0,2; 0,3; und 0,4 mm was inserted between pellets to simulate various pellet to pellet gap. The neutron radiography used had power of 700 kW. The result showed that this simulation represented well enough problems that irradiated fuel element may experience

  19. Pellet injection and toroidal confinement

    International Nuclear Information System (INIS)

    1989-12-01

    The proceedings of a technical committee meeting on pellet injection and toroidal confinement, held in Gut Ising, Federal Republic of Germany, 24-26 October, 1988, are given in this report. Most of the major fusion experiments are using pellet injectors; these were reported at this meeting. Studies of confinement, which is favorably affected, impurity transport, radiative energy losses, and affects on the ion temperature gradient instability were given. Studies of pellet ablation and effects on plasma profiles were presented. Finally, several papers described present and proposed injection guns. Refs, figs and tabs

  20. Measurement of shadowgraph of flying solid-hydrogen pellets

    International Nuclear Information System (INIS)

    Hasegawa, Kouichi; Kasai, Satoshi; Suzuki, Sadaaki; Oda, Yasushi.

    1992-11-01

    The measurement system of shadowgraphs of flying pellets for the high-speed multi-pellet injector is described. Shadowgraphs of pellets ejected repeatedly with 1-5 Hz could be taken with about 100 % probability by using the system, which is composed of a intense pulse-lamp with a video-camera and a timing control system. (author)

  1. Tritium proof-of-principle injector experiment

    International Nuclear Information System (INIS)

    Fisher, P.W.; Milora, S.L.; Combs, S.K.; Carlson, R.V.; Coffin, D.O.

    1988-01-01

    The Tritium Proof-of-Principle (TPOP) pellet injector was designed and built by Oak Ridge National Laboratory (ORNL) to evaluate the production and acceleration of tritium pellets for fueling future fision reactors. The injector uses the pipe-gun concept to form pellets directly in a short liquid-helium-cooled section of the barrel. Pellets are accelerated by using high-pressure hydrogen supplied from a fast solenoid valve. A versatile, tritium-compatible gas-handling system provides all of the functions needed to operate the gun, including feed gas pressure control and flow control, plus helium separation and preparation of mixtures. These systems are contained in a glovebox for secondary containment of tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory (LANL). 18 refs., 3 figs

  2. Axially alignable nuclear fuel pellets

    International Nuclear Information System (INIS)

    Johansson, E.B.; Klahn, D.H.; Marlowe, M.O.

    1978-01-01

    An axially alignable nuclear fuel pellet of the type stacked in end-to-end relationship within a tubular cladding is described. Fuel cladding failures can occur at pellet interface locations due to mechanical interaction between misaligned fuel pellets and the cladding. Mechanical interaction between the cladding and the fuel pellets loads the cladding and causes increased cladding stresses. Nuclear fuel pellets are provided with an end structure that increases plastic deformation of the pellets at the interface between pellets so that lower alignment forces are required to straighten axially misaligned pellets. Plastic deformation of the pellet ends results in less interactions beween the cladding and the fuel pellets and significantly lowers cladding stresses. The geometry of pellets constructed according to the invention also reduces alignment forces required to straighten fuel pellets that are tilted within the cladding. Plastic deformation of the pellets at the pellet interfaces is increased by providing pellets with at least one end face having a centrally-disposed raised area of convex shape so that the mean temperature and shear stress of the contact area is higher than that of prior art pellets

  3. Fish pelleting

    African Journals Online (AJOL)

    PUBLICATIONS1

    fish meal pelletizing machine utilized 4kg of ingredients to produce 3.77kg pellets at an effi- ciency of .... Design and fabrication of fish meal pellet processing machine ... 53 ... horsepower for effective torque application on .... two edges were tacked with a spot weld to hold ... then welded on to the shaft making sure that the.

  4. Considerations of several real effects in pneumatic pellet injection processes

    International Nuclear Information System (INIS)

    Ming-Lun Xue.

    1987-10-01

    Several real effects that take place in a pneumatic pellet injector are examined. These are the heat transfer between a high-temperature propellent gas and the metal wall of the injector, and the frictional loss between the propellent and wall. (author)

  5. Prototype of a high speed pellet launcher for JET

    International Nuclear Information System (INIS)

    Sonnenberg, K.; Kupschus, P.; Helm, J.; Flory, D.; Zacchia, F.

    1989-01-01

    JET is planning to build a high speed prototype pellet injector cap0able of delivering single D 2 -ice pellets, one per plasma pulse, with a velocity of up to 5 kms -1 . The prototype will be based on a 2-stage gun system which is presently being developed at JET using a test stand. One gun of the teststand will be transformed into the prototype used at the torus. Earlier tests have shown that D 2 -ice pellets can only sustain peak accelerations of 5x10 6 ms -2 without breaking and that they suffer from an erosion effect in the barrel limiting the pellet velocity to about 2.7 kms -1 . Results are presented proving that these problems can be overcome by accelerating the ice in a protective sabot (cartridge). With this method velocities of up to 3.8 kms -1 have been obtained. The sabot technique, however, requires a separation of the sabot from the pellet before this is injected into the plasma. Three possible separation methods are described and experimental results of one of them are presented. Also improvements of the gun are discussed which allow to operate the gun by remote control. (author). 5 refs.; 5 figs

  6. Fuel pellet

    International Nuclear Information System (INIS)

    Hayashi, K.

    1980-01-01

    Fuel pellet for insertion into a cladding tube in order to form a fuel element or a fuel rod. The fuel pellet has got a belt-like projection around its essentially cylindrical lateral circumferential surface. The upper and lower edges in vertical direction of this belt-like projection are wave-shaped. The projection is made of the same material as the bulk pellet. Both are made in one piece. (orig.) [de

  7. Uranium dioxide pellets

    International Nuclear Information System (INIS)

    Zawidzki, T.W.

    1979-01-01

    Sintered uranium dioxide pellets composed of particles of size > 50 microns suitable for power reactor use are made by incorporating a small amount of sulphur into the uranium dioxide before sintering. The increase in grain size achieved results in an improvement in overall efficiency when such pellets are used in a power reactor. (author)

  8. Operational results and development of the E.C.R. sources and the injector into CYCLONE

    International Nuclear Information System (INIS)

    Bol, J.L.; Jongen, Y.; Lacroix, M.; Mathy, F.; Ryckewaert, G.

    1985-01-01

    A large superconducting ECR-source (ECREVIS) has been producing high charge state ions up to Xe 27+ for injection into CYCLONE and as a stand alone source for atomic physics for over two years now. An improved analysing system has been installed increasing greatly the acceptance without harming the resolution. Operational results of transmission and realistic charge state distributions are reported. The design of a more compact ECR-source, to be called OCTOPUS and using water cooled copper solenoids, an open permanent magnet octupole structure and an iron yoke is presented. This source will replace ECREVIS and it is expected to have better performance and to be more reliable and economical to operate

  9. Review of pellet fueling

    International Nuclear Information System (INIS)

    Turnbull, R.J.

    1978-01-01

    Fusion reactors based on the Tokamak concept (possibly mirrors, too) will require a low energy method of fueling. Refueling by using solid pellets of hydrogen isotopes appears to be the most promising low energy technique. The main issue in assessing the feasibility of pellet fueling is the ability of the pellet to penetrate into the central region of the reactor. A review is presented of the various theories predicting the lifetime of the pellet and their regions of applicability. Among the phenomena considered are neutral ablation of the solid, ionized ablation of the solid, shielding of the pellet by neutral molecules and electrons and ions, flow of the ablation cloud, distortion of the magnetic field by the flow of an ionized ablation cloud, and charging and electrostatic shielding of the pellet. A brief summary of results of experiments done by the University of Illinois-Oak Ridge and Riso groups is presented. The results of these experiments indicate that, at least at the low temperatures and densities used, a neutral ablation-neutral shielding model is correct. Finally, since all indications are that in order for pellet fueling to be successful, high velocity pellets will be needed, a brief discussion of possible acceleration techniques is presented

  10. Repetitive fueling pellet injection in large helical device

    International Nuclear Information System (INIS)

    Yamada, H.; Sakamoto, R.; Viniar, I.; Oda, Y.; Kikuchi, K.; Lukin, A.; Skoblikov, S.; Umov, A.; Takaura, K.; Onozuka, M.; Kato, S.; Sudo, S.

    2003-01-01

    A repetitive pellet injector has been developed for investigation of fueling issues towards the steady-state operation in Large Helical Device (LHD). The goal of this approach is achievement of the plasma operation for longer than 1000 s. A principal technical element of the pellet injector is solidification of hydrogen and extrusion of a solid hydrogen rod through a cryogenic screw extruder cooled by Giffard-McMahon (GM) cryo-coolers. Continuous operation of more than 10000 pellet launches at 10 Hz has been demonstrated. The reliability of pellet launch exceeds 99%. The pellet mass and velocity, the consumption of propellant gas and quality of pellets have been successfully tested to fit the experimental requirement in LHD

  11. Repetitive fueling pellet injection in large helical device

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, H. E-mail: hyamada@lhd.nifs.ac.jp; Sakamoto, R.; Viniar, I.; Oda, Y.; Kikuchi, K.; Lukin, A.; Skoblikov, S.; Umov, A.; Takaura, K.; Onozuka, M.; Kato, S.; Sudo, S

    2003-09-01

    A repetitive pellet injector has been developed for investigation of fueling issues towards the steady-state operation in Large Helical Device (LHD). The goal of this approach is achievement of the plasma operation for longer than 1000 s. A principal technical element of the pellet injector is solidification of hydrogen and extrusion of a solid hydrogen rod through a cryogenic screw extruder cooled by Giffard-McMahon (GM) cryo-coolers. Continuous operation of more than 10000 pellet launches at 10 Hz has been demonstrated. The reliability of pellet launch exceeds 99%. The pellet mass and velocity, the consumption of propellant gas and quality of pellets have been successfully tested to fit the experimental requirement in LHD.

  12. Design and Results of a Time Resolved Spectrometer for the 5 MeV Photo-Injector Phin

    CERN Document Server

    Dabrowski, A; Egger, D; Mete, O; Lefevre, T

    2010-01-01

    The CLIC Test Facility 3 (CTF3) drive beam injector should provide high intensity and high quality electron beams. The present installation relies on a thermionic gun followed by a complex RF bunching system. As an upgrade to improve the beam emittance and the energy spread and to minimize the beam losses, a photo-injector is being developed and tested at CERN. One of the major challenges is to provide a 3.5A beam with a stable (0.1%) beam energy over 1.2 μs and a relative energy spread smaller than 1%. A 90◦ spectrometer line consisting of a segmented dump and an Optical Transition Radiation screen has been built in order to study these issues. The following paper describes its design and shows performances during the beam commissioning.

  13. From a single pellet press to a bench scale pellet mill - Pelletizing six different biomass feedstocks

    DEFF Research Database (Denmark)

    Puig Arnavat, Maria; Shang, Lei; Sárossy, Zsuzsa

    2016-01-01

    The increasing demand for biomass pellets requires the investigation of alternative raw materials for pelletizetion. In the present paper, the pelletization process of fescue, alfalfa, sorghum, triticale, miscanthus and willow is studied to determine if results obtained in a single pellet press (...

  14. Pneumatic injector of deuterium macroparticles for TORE-SUPRA tokamak

    International Nuclear Information System (INIS)

    Vinyar, I.V.; Umov, A.P.; Lukin, A.Ya.; Skoblikov, S.V.; Reznichenko, P.V.; Krasil'nikov, I.A.

    2006-01-01

    The pneumatic injector for periodic injection of fuel-solid-deuterium pellets into the plasma of the TORE-SUPRA tokamak in a steady-state mode is described. The deuterium pellet injection with an unlimited duration is ensured by a screw extruder in which gaseous deuterium is frozen and squeezed outwards in the form of a rod with a rectangular cross section. A cutter installed on the injector's barrel cuts a cylinder with a diameter of 2 mm and a length of 1.0-3.5 mm out from this rod. The movement of the cutter is controlled by a pulsed electromagnetic drive at a pulse repetition rate of 10 Hz. In the injector's barrel, a compressed gas accelerates a deuterium pellet to a velocity of 100-650 m/s [ru

  15. ANL high resolution injector

    International Nuclear Information System (INIS)

    Minehara, E.; Kutschera, W.; Hartog, P.D.; Billquist, P.

    1985-01-01

    The ANL (Argonne National Laboratory) high-resolution injector has been installed to obtain higher mass resolution and higher preacceleration, and to utilize effectively the full mass range of ATLAS (Argonne Tandem Linac Accelerator System). Preliminary results of the first beam test are reported briefly. The design and performance, in particular a high-mass-resolution magnet with aberration compensation, are discussed. 7 refs., 5 figs., 2 tabs

  16. Monitoring and data acquisition of the high speed hydrogen pellet in SPINS

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Samiran Shanti, E-mail: samiran@ipr.res.in; Mishra, Jyotishankar; Gangradey, Ranjana; Dutta, Pramit; Rastogi, Naveen; Panchal, Paresh; Nayak, Pratik; Agarwal, Jyoti; Bairagi, Pawan; Patel, Haresh; Sharma, Hardik

    2016-11-15

    Highlights: • Pellet INjector System with monitoring and data acquisition is described. • A high speed camera was used to view pellet size, and its flight trajectory. • PXI based high speed control system is used data acquisition. • Pellets of length 2–4.8 mm and speed 250–750 m/s were obtained. - Abstract: Injection of solid hydrogen pellets is an efficient way of replenishing the spent fuel in high temperature plasmas. Aiming that, a Single Pellet INjector System (SPINS) is developed at Institute for Plasma Research (IPR), India, to initiate pellet injection related research in SST-1. The pellet injector is controlled by a PXI system based data acquisition and control (DAC) system for pellet formation, precise firing control, data collection and diagnostics. The velocity of high speed moving pellets is estimated by using two sets of light gate diagnostic. Apart from light gate, a fast framing camera is used to measure the pellet size and its speed. The pellet images are captured at a frame rate of ∼200,000 frames per second at (128 × 64) pixel resolution with an exposure time of 1 μs. Using these diagnostic, various cylindrical pellets of length ranging from 2 to 4.8 mm and speed 250–750 m/s were successfully obtained. This paper describes the control and data acquisition system of SPINS, the techniques for measurement of pellet velocity and capturing images of high speed moving pellet.

  17. Production and ejection of solid hydrogen-isotope pellet (single pellet)

    International Nuclear Information System (INIS)

    Kasai, Satoshi; Hasegawa, Koichi; Miura, Yukitoshi; Ishibori, Ikuo

    1986-03-01

    The pneumatic gun type pellet injector (single pellet) has been constructed, which is basic type used at ORNL. The pellet in the carrier is 1.65 mm in diameter and 1.65 mm in length, and another is 1 mmD x 1 mmL. Hydrogen pellet velocity of about 900 m/s was observed at propellant gas (He) pressure of 14 kg/cm 2 . In the injection experiment into a plasma, typical velocity is 714 ∼ 833 m/s. These values are 80 ∼ 95 % of velocity calculated from the ideal gun model. The ejected pellet size is 71 ∼ 90 % of the hole size in the carrier disk (1.65 mmD x 1.65 mmL) and 46 ∼ 56 % (1 mmD x 1 mmL). The spread in the pellet trajectories is about 26 mm in diameter at a plasma center. (author)

  18. Injector MD Days 2017

    CERN Document Server

    Rumolo, G

    2017-01-01

    The Injector Machine Development (MD) days 2017 were held on 23-24 March, 2017, at CERN with thefollowing main goals:Give a chance to the MD users to present their results and show the relevant progress made in 2016 onseveral fronts.Provide the MD users and the Operation (OP) crews with a general overview on the outcome and theimpact of all ongoing MD activities.Identify the open questions and consequently define - with priorities - a list of machine studies in theinjectors for 2017 (covering the operational beams, LHC Injectors Upgrade, High Luminosity LHC,Physics Beyond Colliders, other projects).Create the opportunity to collect and document the highlights of the 2016 MDs and define the perspectivesfor 2017.Discuss how to make best use of the MD time, in particular let the main MD user express their wishesand see whether/how OP teams can contribute to their fulfilment.

  19. Development of pellet injection systems for ITER

    International Nuclear Information System (INIS)

    Combs, S.K.; Gouge, M.J.; Baylor, L.R.

    1995-01-01

    Oak Ridge National Laboratory (ORNL) has been developing innovative pellet injection systems for plasma fueling experiments on magnetic fusion confinement devices for about 20 years. Recently, the ORNL development has focused on meeting the complex fueling needs of the International Thermonuclear Experimental Reactor (ITER). In this paper, we describe the ongoing research and development activities that will lead to a ITER prototype pellet injector test stand. The present effort addresses three main areas: (1) an improved pellet feed and delivery system for centrifuge injectors, (2) a long-pulse (up to steady-state) hydrogen extruder system, and (3) tritium extruder technology. The final prototype system must be fully tritium compatible and will be used to demonstrate the operating parameters and the reliability required for the ITER fueling application

  20. CFD simulation of coaxial injectors

    Science.gov (United States)

    Landrum, D. Brian

    1993-01-01

    injectors. The following sections will discuss the physical aspects of injectors, the CFD code employed, and preliminary results of a simulation of a single coaxial injector for which experimental data is available. It is hoped that this work will lay the foundation for the development of a unique and useful tool to support the SSME program.

  1. Make-up of injector test stand (ITS-1) and preliminary results with Model-I ion source

    International Nuclear Information System (INIS)

    Matsuda, S.; Ito, T.; Kondo, U.; Ohara, Y.; Oga, T.; Shibata, T.; Shirakata, H.; Sugawara, T.; Tanaka, S.

    Constitution of the 1-st injector test stand (ITS-1) in the Thermonuclear Division, JAERI, and the performance of the Model-I ion source are described. Heating a plasma by neutral beam injection is one of the promising means in the thermonuclear fusion devices. Purpose of the test stand is to develop the ion sources used in such injection systems. The test stand was completed in February 1975, which is capable of testing the ion sources up to 12 amps at 30 kV. A hydrogen ion beam of 5.5 amps at 25 kV was obtained in the Model-I ion source

  2. Alternative Bio-Derived JP-8 Class Fuel and JP-8 Fuel: Flame Tube Combustor Test Results Compared using a GE TAPS Injector Configuration

    Science.gov (United States)

    Hicks, Yolanda R.; Anderson, Robert; Tedder, Sarah

    2016-01-01

    This paper presents results from tests in a NASA Glenn Research Center (GRC) flame tube facility, where a bio-derived alternate fuel was compared with JP-8 for emissions and general combustion performance. A research version of General Electric Aviation (GE) TAPS injector was used for the tests. Results include 2D, planar laser-based imaging as well as basic flow visualization of the flame. Four conditions were selected that simulate various engine power conditions relevant to NASA Fundamental Aeronautics Supersonics and Environmentally Responsible Aviation Projects were tested.

  3. Pellet imaging techniques on ASDEX

    International Nuclear Information System (INIS)

    Wurden, G.A.; Buechl, K.; Hofmann, J.; Lang, R.; Loch, R.; Rudyj, A.; Sandmann, W.

    1990-01-01

    As part of a USDOE/ASDEX collaboration, a detailed examination of pellet ablation in ASDEX with a variety of diagnostics has allowed a better understanding of a number of features of hydrogen ice pellet ablation in a plasma. In particular, fast gated photos with an intensified Xybion CCD video camera allow in-situ velocity measurements of the pellet as it penetrates the plasma. With time resolution of typically 100 nanoseconds and exposures every 50 microseconds, the evolution of each pellet in a multi-pellet ASDEX tokamak plasma discharge can be followed. When the pellet cloud track has striations, the light intensity profile through the cloud is hollow (dark near the pellet), whereas at the beginning or near the end of the pellet trajectory the track is typically smooth (without striations) and has a gaussian-peaked light emission profile. New, single pellet Stark broadened D α D β , and D γ spectra, obtained with a tangentially viewing scanning mirror/spectrometer with Reticon array readout, are consistent with cloud densities of 2 x 10 17 cm -3 or higher in the regions of strongest light emission. A spatially resolved array of D α detectors shows that the light variations during the pellet ablation are not caused solely by a modulation of the incoming energy flux as the pellet crosses rational q-surfaces, but instead are a result of a dynamic, non-stationary, ablation process. 20 refs., 4 figs

  4. Using one-dimensional modeling to analyze the influence of the use of biodiesels on the dynamic behavior of solenoid-operated injectors in common rail systems: Results of the simulations and discussion

    International Nuclear Information System (INIS)

    Salvador, F.J.; Gimeno, J.; De la Morena, J.; Carreres, M.

    2012-01-01

    Highlights: ► Effect of using diesel or biodiesel on injector hydraulic behavior has been analyzed. ► Single and main + post injections have been studied for different injection pressures. ► Higher viscosity affects needle dynamics, especially for low injection pressure. ► The post injection masses are lower for biodiesel fuel despite its higher density. ► Modified injector has been proposed to compensate the differences between the fuels. - Abstract: The influence of using biodiesel fuels on the hydraulic behavior of a solenoid operated common rail injection system has been explored by means of a one-dimensional model. This model has been previously obtained, including a complete characterization of the different components of the injector (mainly the nozzle, the injector holder and the electrovalve), and extensively validated by means of mass flow rate results under different conditions. After that, both single and multiple injection strategies have been analyzed, using a standard diesel fuel and rapeseed methyl ester (RME) as working fluids. Single long injections allowed the characterization of the hydraulic delay of the injector, the needle dynamics and the discharge capability of the couple injector-nozzle for the two fuels considered. Meanwhile, the effect of biodiesel on main plus post injection strategies has been evaluated in several aspects, such as the separation of the two injections or the effect of the main injection on the post injection fueling. Finally, a modification in the injector hardware has been proposed in order to have similar performances using biodiesel as the original injector configuration using standard diesel fuel.

  5. SLC injector modeling

    International Nuclear Information System (INIS)

    Hanerfeld, H; Herrmannsfeldt, W.B.; James, M.B.; Miller, R.H.

    1985-03-01

    The injector for the Stanford Linear Collider is being studied using the fully electromagnetic particle-in-cell program MASK. The program takes account of cylindrically symmetrical rf fields from the external source, as well as fields produced by the beam and dc magnetic fields. It calculates the radial and longitudinal motion of electrons and plots their positions in various planes in phase space. Bunching parameters can be optimized and insights into the bunching process and emittance growth have been gained. The results of the simulations are compared to the experimental results

  6. New pellet production and acceleration technologies for high speed pellet injection system 'HIPEL' in large helical device

    International Nuclear Information System (INIS)

    Viniar, I.; Sudo, S.

    1994-12-01

    New technologies of pellet production and acceleration for fueling and diagnostics purposes in large thermonuclear reactors are proposed. The technologies are intended to apply to the multiple-pellet injection system 'HIPEL' for Large Helical Device of NIFS in Japan. The pellet production technology has already been tested in a pipe-gun type pellet injector. It will realize the repeating pellet injection by means of decreasing of the pellet formation time into the pipe-gun barrel. The acceleration technology is based upon a new pump tube operation in two-stage gas gun and also upon a new conception of the allowable pressure acting on a pellet into a barrel. Some preliminary estimations have been made, and principles of a pump tube construction providing for a reliable long term operation in the repeating mode without any troubles from a piston are proposed. (author)

  7. Pellet fueling development at ORNL

    International Nuclear Information System (INIS)

    Combs, S.K.; Milora, S.L.; Foster, C.A.; Schuresko, D.D.; Foust, C.R.; Simmons, D.W.; Beard, D.S.

    1986-09-01

    Advanced plasma fueling systems for magnetic confinement devices are being developed at the Oak Ridge National Laboratory (ORNL). The general approach is that of producing and accelerating frozen hydrogenic pellets at speeds in the range of 1-2 km/s and higher. Two specific concepts are under development: (1) high-speed pneumatic acceleration; and (2) mechanical (centrifugal) acceleration. Both approaches are being pursued to meet the projected pellet size and delivery rates for major near-term plasma confinement devices, such as the Tokamak Fusion Test Reactor (TFTR), Tore Supra, the Joint European Torus (JET), JT-60, and Doublet III-D (DIII-D), as well as future applications. In addition to these confinement physics related activities, ORNL is pursuing advanced technologies to achieve pellet velocities significantly in excess of the 2-km/s range already attained with pneumatic injectors and has embarked on a development program designed to explore the feasibility of fabricating and accelerating tritium pellets. This paper describes these ongoing activities

  8. Power matching for pellet fusion

    International Nuclear Information System (INIS)

    Martin, R.L.; Arnold, R.C.

    1976-01-01

    The number of beams required for optimum power transfer from a given power source to the surface of a pellet is derived. The result is valid for linear optical systems, hence, for pellet fusion by laser or high energy ion beams. The optimum number of beams turns out to be inconceivably large for any practical system. Practical pellet fusion by lasers or high energy heavy ion beams must thus compromise physical principles in favor of reduced cost and optical complexity

  9. Usability of devices for self-injection: results of a formative study on a new disposable pen injector

    Directory of Open Access Journals (Sweden)

    Lange J

    2014-06-01

    Full Text Available Jakob Lange,1 Philipp Richard,1 Nick Bradley21Ypsomed AG, Burgdorf, Switzerland; 2Bergo, Glasgow, United KingdomAbstract: This article presents a late-stage formative usability study of a pen-injector platform device. Such devices are used for the subcutaneous delivery of biopharmaceuticals, primarily for self-administration by the patient. The study was conducted with a broad user population, defined to represent user characteristics across a range of indications. The goals of the study were to confirm that the pen could be used without recurring patterns of use errors leading to hazardous situations, to evaluate the comprehension of the instructions for use (IFU, and to determine if training is necessary. In the study, a total of 36 participants in six groups (health care providers, caregivers, adolescents, diabetics with retinopathy, diabetics with neuropathy, and patients with arthritis each read the IFU, prepared the device, and performed two simulated injections into an injection pad. Any use errors, near misses, or deviations from the IFU procedure were recorded. The overall success rate (injection completed by the participant without need for assistance was 94% for the first and 100% for the second injection. Ninety-two percent of the participants reported that they felt confident using the device, 100% found the IFU helpful, and 75% found the device positively comfortable to use. Overall, a total average of 3.35 deviations and errors per user and injection were recorded (there were no near misses. Subtracting the errors without any potential for negative consequences for the injection or the user (trivial deviations, as well as those related to attaching and removing the pen needle (independent of the design of the pen itself, led to an average of 1.31 potentially relevant deviations per user and injection. It was concluded that the pen injector together with the IFU could be safely and efficiently used by all user groups without any

  10. CNG INJECTOR RESEARCH FOR DUAL FUEL ENGINE

    Directory of Open Access Journals (Sweden)

    Adam Majczak

    2017-03-01

    Full Text Available The article presents the tests results of the prototype design of hydraulically assisted injector, that is designed for gas supply into diesel engines. The construction of the injector allows for it positioning in the glow plug socket, so that the gas is injected directly into the combustion chamber. The cycle analysis of the four-cylinder Andoria ADCR engine with a capacity of 2.6 dm3 for different crankshaft rotational speeds allowed to determine the necessary time for fuel injection. Because of that, it was possible to determine the required mass flow rate of the injector, for replacing as much of the original fuel by gaseous fuel. To ensure a high value of flow inside the injector, supply pressure equal to 1 MPa was applied. High gas supply pressure requires high value of valve opening forces. For this purpose a injector with hydraulic control system, using a liquid under pressure for the opening process was designed. On the basis of air pressure measurements in the flow line after the injector, the analysis of opening and closing of the valve was made. Measurements of outflow mass of the injector were also carried out. The results showed that the designed injector meets the requirements necessary to supply ADCR engine by the CNG fuel.

  11. Ranking of lignocellulosic biomass pellets through multicriteria modeling

    Energy Technology Data Exchange (ETDEWEB)

    Sultana, A.; Kumar, A. [Alberta Univ., Edmonton, AB (Canada). Dept. of Mechanical Engineering

    2009-07-01

    A study was conducted in which pellets from different lignocellulosic biomass sources were ranked using a multicriteria assessment model. Five different pellet alternatives were compared based on 10 criteria. The pair-wise comparison was done in order to develop preference indices for various alternatives. The methodology used in this study was the Preference Ranking Organization Method for Enrichment and Evaluation (PROMETHEE). The biomass included wood pellets, straw pellets, switchgrass pellets, alfalfa pellets and poultry pellets. The study considered both quantitative and qualitative criteria such as energy consumption to produce the pellets, production cost, bulk density, NOx emissions, SOx emissions, deposit formation, net calorific value, moisture content, maturity of technology, and quality of material. A sensitivity analysis was performed by changing weights of criteria and threshold values of the criteria. Different scenarios were developed for ranking cost and environmental impacts. According to preliminary results, the wood pellet is the best energy source, followed by switchgrass pellets, straw pellets, alfalfa pellets and poultry pellets.

  12. Treatment adherence with the easypod™ growth hormone electronic auto-injector and patient acceptance: survey results from 824 children and their parents

    Directory of Open Access Journals (Sweden)

    Larroque Sylvain

    2011-02-01

    Full Text Available Abstract Background Accurately monitoring adherence to treatment with recombinant human growth hormone (r-hGH enables appropriate intervention in cases of poor adherence. The electronic r-hGH auto-injector, easypod™, automatically records the patient's adherence to treatment. This study evaluated adherence to treatment of children who started using the auto-injector and assessed opinions about the device. Methods A multicentre, multinational, observational 3-month survey in which children received r-hGH as part of their normal care. Physicians reviewed the recorded dose history and children (with or without parental assistance completed a questionnaire-based survey. Children missing ≤2 injections per month (92% of injections given were considered adherent to treatment. Adherence was compared between GH treatment-naïve and treatment-experienced children. Results Of 834 recruited participants, 824 were evaluated. The median (range age was 11 (1-18 years. From the recorded dose history, 87.5% of children were adherent to treatment over the 3-month period. Recorded adherence was higher in treatment-naïve (89.7%, n = 445/496 than in treatment-experienced children (81.7%, n = 152/186 [Fisher's exact test FI(X = 7.577; p = 0.0062]. According to self-reported data, 90.2% (607/673 of children were adherent over 3 months; 51.5% (421/817 missed ≥1 injection over this period (mainly due to forgetfulness. Concordance between reported and recorded adherence was 84.3%, with a trend towards self-reported adherence being higher than recorded adherence. Most children liked the auto-injector: over 80% gave the top two responses from five options for ease of use (720/779, speed (684/805 and comfort (716/804. Although 38.5% (300/780 of children reported pain on injection, over half of children (210/363 considered the pain to be less or much less than expected. Given the choice, 91.8% (732/797 of children/parents would continue using the device. Conclusions

  13. First demonstration of laser engagement of 1-Hz-injected flying pellets and neutron generation

    Science.gov (United States)

    Komeda, Osamu; Nishimura, Yasuhiko; Mori, Yoshitaka; Hanayama, Ryohei; Ishii, Katsuhiro; Nakayama, Suisei; Kitagawa, Yoneyoshi; Sekine, Takashi; Sato, Nakahiro; Kurita, Takashi; Kawashima, Toshiyuki; Kan, Hirofumi; Nakamura, Naoki; Kondo, Takuya; Fujine, Manabu; Azuma, Hirozumi; Motohiro, Tomoyoshi; Hioki, Tatsumi; Kakeno, Mitsutaka; Sunahara, Atsushi; Sentoku, Yasuhiko; Miura, Eisuke

    2013-01-01

    Pellet injection and repetitive laser illumination are key technologies for realizing inertial fusion energy. Numerous studies have been conducted on target suppliers, injectors, and tracking systems for flying pellet engagement. Here we for the first time demonstrate the pellet injection, counter laser beams' engagement and neutron generation. Deuterated polystyrene (CD) bead pellets, after free-falling for a distance of 18 cm at 1 Hz, are successfully engaged by two counter laser beams from a diode-pumped, ultra-intense laser HAMA. The laser energy, pulse duration, wavelength, and the intensity are 0.63 J per beam, 104 fs, and 811 nm, 4.7 × 1018 W/cm2, respectively. The irradiated pellets produce D(d,n)3He-reacted neutrons with a maximum yield of 9.5 × 104/4π sr/shot. Moreover, the laser is found out to bore a straight channel with 10 μm-diameter through the 1-mm-diameter beads. The results indicate potentially useful technologies and findings for the next step in realizing inertial fusion energy. PMID:24008696

  14. Pelletizing properties of torrefied spruce

    DEFF Research Database (Denmark)

    Stelte, Wolfgang; Clemons, Craig; Holm, Jens K.

    2011-01-01

    analysis revealed a cohesive failure mechanism due to strong inter-particle bonding in spruce pellets as a resulting from a plastic flow of the amorphous wood polymers, forming solid polymer bridges between adjacent particles. Fracture surfaces of pellets made from torrefied spruce possessed gaps and voids...

  15. Assessment of pelletized biofuels

    International Nuclear Information System (INIS)

    Samson, R.; Duxbury, P.; Drisdelle, M.; Lapointe, C.

    2000-04-01

    There has been an increased interest in the development of economical and convenient renewable energy fuels, resulting from concerns about climate change and rising oil prices. An opportunity to use agricultural land as a means of producing renewable fuels in large quantities, relying on wood and agricultural residues only has come up with recent advances in biomass feedstock development and conversion technologies. Increasing carbon storage in the landscape and displacing fossil fuels in combustion applications can be accomplished by using switchgrass and short rotation willow which abate greenhouse gas emissions. The potential of switchgrass and short rotation willow, as well as other biomass residues as new feedstocks for the pellet industry is studied in this document. Higher throughput rates are facilitated by using switchgrass, which shows potential as a pelleting feedstock. In addition, crop drying requires less energy than wood. By taking into consideration energy for switchgrass production, transportation to the conversion facility, preprocessing, pelleting, and marketing, the overall energy balance of switchgrass is 14.5:1. Research on alfalfa pelleting can be applied to switchgrass, as both exhibit a similar behaviour. The length of chop, the application of high temperature steam and the use of a die with a suitable length/diameter ratio are all factors that contribute to the successful pelleting of switchgrass. Switchgrass has a similar combustion efficiency (82 to 84 per cent) to wood (84 to 86 per cent), as determined by combustion trials conducted by the Canada Centre for Mineral and Energy Technology (CANMET) in the Dell-Point close coupled gasifier. The energy content is 96 per cent of the energy of wood pellets on a per tonne basis. Clinker formation was observed, which necessitated some adjustments of the cleaner grate settings. While stimulating rural development and export market opportunities, the high yielding closed loop biofuels show

  16. Operation and reliability of a pneumatic hydrogen pellet injection system on the Joint European Torus

    International Nuclear Information System (INIS)

    Combs, S.K.; Jernigan, T.C.; Baylor, L.R.; Milora, S.L.; Foust, C.R.; Kupschus, P.; Gadeberg, M.; Bailey, W.; Commission of the European Communities, Abingdon

    1989-01-01

    A pneumatic-based, hydrogen isotope pellet injector that was developed at the Oak Ridge National Laboratory for the plasma fueling application on the Joint European Torus (JET) was described at the last Symposium on Fusion Engineering (1987). The injector was installed on JET during 1987 and has since been used in plasma fueling experiments. The injector consists of three independent machine-gun-like mechanisms (nominal pellet sizes of 2.7, 4.0, and 6.0 mm in diameter), and it features repetitive operation (1-5 Hz) for quasi-steady-state conditions (>10 s). An extensive set of injector diagnostics permits evaluation of parameters for each pellet shot, including speed, mass, and integrity. Pellet speeds can be varied but typically range from 1.0 to 1.5 km/s. Over 5000 pellets have been fired with the equipment at JET, including about 2000 pellets shot for plasma fueling experiments. In recent experiments, the system performance has been outstanding, including excellent reproducibility in pellet speed and mass and a reliability of >98% in delivery of pellets to the plasma. 7 refs., 5 figs

  17. Understanding the spectrum of diesel injector deposits

    Energy Technology Data Exchange (ETDEWEB)

    Quigley, Robert; Barbour, Robert [Lubrizol Limited, Derby (United Kingdom); Arters, David; Bush, Jim [Lubrizol Corporation, Wickliffe, OH (United States)

    2013-06-01

    Understanding the origin of diesel fuel injector deposits used to be relatively simple; for the most part they were caused by the decomposition of fuel during the combustion process, were generally organic in nature and typically only affected the nozzle orifices. However, modem fuel injector designs appear to be both more severe in terms of generating conditions conducive to creating new and different types of deposits and more likely to have their operation affected by those deposits. Changes to fuel composition and type have in some cases increased the potential pool of reactive species or provided new potential deposit precursors. As a result, the universe of diesel injector deposits now range from the traditional organic to partially or fully inorganic in nature and from nozzle coking deposits to deposits which can seize the internal components of the injector; so called internal diesel injector deposits. Frequently, combinations of inorganic and organic deposits are found. While power loss is one well known issue associated with nozzle deposits, other field problems resulting from these new deposits include severe issues with drivability, emissions, fuel consumption and even engine failure. Conventional deposit control additive chemistries were developed to be effective against organic nozzle coking deposits. These conventional additives in many cases may prove ineffective against this wide range of deposit types. This paper discusses the range of deposits that have been found to adversely impact modem diesel fuel injectors and compares the performance of conventional and new, advanced deposit control additives against these various challenges to proper fuel injector functioning. (orig.)

  18. Hydrogen pellet injection into Alcator C

    International Nuclear Information System (INIS)

    Greenwald, M.

    1983-09-01

    A four-shot pneumatic pellet injector, based on an ORNL design, has been built and operated on the Alcator C tokamak at MIT. The injector fires four independently-timed frozen hydrogen pellets with velocities in the range 8 x 10 4 - 1 x 10 5 cm/sec. Each contains 6 x 10 19 particles which corresponds to = 2 x 10 14 /cm 3 . The objectives of this experiment are to study pellet fueling and penetration, particle confinement, dependence of energy confinement on density profile and fueling mode, and edge physics and recycling as a function of fueling mode. Typical pre-injection plasmas have had anti n/sub e/ = 2 - 3 x 10 14 , Bt = 80 - 100 kG, Ip = 400 - 500 kA, T/sub e/(0) = 1200 - 1500 ev. A single pellet injected into this plasma will roughly double the electron density. Record plasma densities have been obtained by multiple injections. Line average densities in excess of 8 x 10 14 have been achieved, with highly peaked profiles. Central densities of 1.5 - 2 x 10 15 have been measured

  19. Pellet dimension checker

    International Nuclear Information System (INIS)

    Marmo, A.R.

    1980-01-01

    A pellet dimension checker was developed for use in making nuclear-fuel pellets. This checker eliminates operator handling of the pellet but permits remote-monitoring of the operation, and is thus suitable for mass production of green fuel pellets particularly in reprocessing plants handling irradiated uranium or plutonium. It comprises a rotatable arm for transferring a pellet from a conveyor to several dimensional measuring stations and back to the conveyor if the dimensions of the pellet are within predetermined limits. If the pellet is not within the limits, the arm removes the pellet from the process stream. (DN)

  20. Injector of solid indicator

    Energy Technology Data Exchange (ETDEWEB)

    Chernyshev, G.I.; Luk' yanov, E.P.; Pruslin, Y.A.; Zabrodin, P.I.

    1981-04-25

    The injector can be used with remote introduction of indicators into a borehole for study in an oil well of the parameters of movement of fluid currents, control of the state of the equipment, and study of the properties of the rocks. Proposed is a method of increasing the reliability of operation of the injector by stabilizing the rate of its dispersing. Introduced to the injector of a solid indicator are auxiliary brackets and a cathode made from nonmetallic electrical conducting material and reinforced at the end by an elastic bracket. The auxillary cathode is attached to the end surface of the anode and cathode.

  1. Redirecting by Injector

    Science.gov (United States)

    Filman, Robert E.; Lee, Diana D.; Norvig, Peter (Technical Monitor)

    2000-01-01

    We describe the Object Infrastructure Framework, a system that seeks to simplify the creation of distributed applications by injecting behavior on the communication paths between components. We touch on some of the ilities and services that can be achieved with injector technology, and then focus on the uses of redirecting injectors, injectors that take requests directed at a particular server and generate requests directed at others. We close by noting that OIF is an Aspect-Oriented Programming system, and comparing OIF to related work.

  2. Swirl Coaxial Injector Testing with LOX/RP-J

    Science.gov (United States)

    Greene, Sandra Elam; Casiano, Matt

    2013-01-01

    Testing was conducted at NASA fs Marshall Space Flight Center (MSFC) in the fall of 2012 to evaluate the operation and performance of liquid oxygen (LOX) and kerosene (RP ]1) in an existing swirl coaxial injector. While selected Russian engines use variations of swirl coaxial injectors, component level performance data has not been readily available, and all previously documented component testing at MSFC with LOX/RP ]1 had been performed using a variety of impinging injector designs. Impinging injectors have been adequate for specific LOX/RP ]1 engine applications, yet swirl coaxial injectors offer easier fabrication efforts, providing cost and schedule savings for hardware development. Swirl coaxial elements also offer more flexibility for design changes. Furthermore, testing with LOX and liquid methane propellants at MSFC showed that a swirl coaxial injector offered improved performance compared to an impinging injector. So, technical interest was generated to see if similar performance gains could be achieved with LOX/RP ]1 using a swirl coaxial injector. Results would allow such injectors to be considered for future engine concepts that require LOX/RP ]1 propellants. Existing injector and chamber hardware was used in the test assemblies. The injector had been tested in previous programs at MSFC using LOX/methane and LOX/hydrogen propellants. Minor modifications were made to the injector to accommodate the required LOX/RP ]1 flows. Mainstage tests were performed over a range of chamber pressures and mixture ratios. Additional testing included detonated gbombs h for stability data. Test results suggested characteristic velocity, C*, efficiencies for the injector were 95 ]97%. The injector also appeared dynamically stable with quick recovery from the pressure perturbations generated in the bomb tests.

  3. Raw materials for pellets; Rohstoffe fuer Pellets

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, H.

    2008-01-15

    In order to keep the pellet prices stable, producers look for new raw materials. Sawdust as a former basis also competes with the manufacturers of chip boards and paper. Three classes of quality are discussed by the pellet manufacturers: (a) the DINplus pellet as a premium segment for which high-quality sawdust are used; (b) a wood pellet from natural wood with varying quality for the utilization in larger plants with filters; (c) the inexpensive industrial wood pellet which deviates from the DINplus commodity regarding to the ingredients and form and could be fired in larger power stations.

  4. An overview of CFD modelling of small-scale fixed-bed biomass pellet boilers with preliminary results from a simplified approach

    International Nuclear Information System (INIS)

    Chaney, Joel; Liu Hao; Li Jinxing

    2012-01-01

    Highlights: ► Overview of the overall approach of modelling fixed-bed biomass boilers in CFD. ► Bed sub-models of moisture evaporation, devolatisation and char combustion reviewed. ► A method of embedding a combustion model in discrete fuel zones within the CFD is suggested. ► Includes sample of preliminary results for a 50 kW pellet boiler. ► Clear physical trends predicted. - Abstract: The increasing global energy demand and mounting pressures for CO 2 mitigation call for increased efficient utilization of biomass, particularly for heating domestic and commercial buildings. The authors of the present paper are investigating the optimization of the combustion performance and NO x emissions of a 50 kW biomass pellet boiler fabricated by a UK manufacturer. The boiler has a number of adjustable parameters including the ratio of air flow split between the primary and secondary supplies, the orientation, height, direction and number of the secondary inlets. The optimization of these parameters provides opportunities to improve both the combustion efficiency and NO x emissions. When used carefully in conjunction with experiments, Computational Fluid Dynamics (CFD) modelling is a useful tool for rapidly and at minimum cost examining the combustion performance and emissions from a boiler with multiple variable parameters. However, modelling combustion and emissions of a small-scale biomass pellet boiler is not trivial and appropriate fixed-bed models that can be coupled with the CFD code are required. This paper reviews previous approaches specifically relevant to simulating fixed-bed biomass boilers. In the first part it considers approaches to modelling the heterogeneous solid phase and coupling this with the gas phase. The essential components of the sub-models are then overviewed. Importantly, for the optimization process a model is required that has a good balance between accuracy in predicting physical trends, with low computational run time. Finally, a

  5. Pellet injection into ASDEX upgrade plasmas

    International Nuclear Information System (INIS)

    Lang, P.T.; Zohm, H.; Buechl, K.; Fuchs, J.C.; Gehre, O.; Gruber, O.; Lang, R.S.; Mertens, V.; Neuhauser, J.; Salzmann, H.

    1996-04-01

    This work comprises results obtained using the new centrifuge injection system for the two first years of pellet injection experiments at Asdex Upgrade until the end of the 1995 experimental campaign. The main aim of the pellet injection investigation is to develop scenarios allowing for a more flexible plasma density control means of injection of cryogenic solid hydrogen pellets. Efforts have been made to develop scenarios allowing more flexible plasma density control by injecting cryogenic solid hydrogen pellets. While the injection of pellets during ohmic discharges was found to be most efficient and also improves the plasma performance, increasing the auxiliary heating power causes a detoriation of the pellet fuelling efficiency. A further strong reduction of the pellet fuelling efficiency by an additional process was observed for the more reactor-relevant conditions of shallow particle deposition during H-mode phases. With injection during type I ELMy H-mode phases, each pellet was found to trigger the release of an ELM and therefore cause particle losses mainly from the edge region. In the type I ELMy H-mode, only sufficient pellet penetration allowed noticeable, persistent particle deposition in the plasma by the pellets. Applying adequate pellet injection conditions and favourable scenarios using combined pellet/gas puff refuelling, significant density ramp-up to densities exceeding the empirical Greenwald limit by up to a factor of two was achieved even for strongly heated H-mode plasmas. (orig.)

  6. Electron linac injector developments

    International Nuclear Information System (INIS)

    Fraser, J.S.

    1986-01-01

    There is a continuing demand for improved injectors for electron linacs. Free-electron laser (FEL) oscillators require pulse trains of high brightness and, in some applications, high average power at the same time. Wakefield-accelerator and laser-acceleration experiments require isolated bunches of high peak brightness. Experiments with alkali-halide photoemissive and thermionic electron sources in rf cavities for injector applications are described. For isolated pulses, metal photocathodes (illuminated by intense laser pulses) are being employed. Reduced emittance growth in high-peak-current electron injectors may be achieved by linearizing the cavity electric field's radial component and by using high field strengths at the expense of lower shunt impedance. Harmonically excited cavities have been proposed for enlarging the phase acceptance of linac cavities and thereby reducing the energy spread produced in the acceleration process. Operation of injector linacs at a subharmonic of the main linac frequency is also proposed for enlarging the phase acceptance

  7. PELLET: a computer routine for modeling pellet fueling in tokamak plasmas

    International Nuclear Information System (INIS)

    Houlberg, W.A.; Iskra, M.A.; Howe, H.C.; Attenberger, S.E.

    1979-01-01

    Recent experimental results of frozen hydrogenic pellet injection into hot tokamak plasmas and substantial agreement with theoretical predictions have led to a much greater interest in pellets as a means of refueling plasmas. The computer routine PELLET has been developed and used as an aid in assessing pellet ablation models and the effects of pellets on plasma behavior. PELLET provides particle source profiles under various options for the ablation model and can be coupled either to a fluid transport code or to a brief routine which supplies the required input parameters

  8. Pneumatic hydrogen pellet injection system for the ISX tokamak

    International Nuclear Information System (INIS)

    Milora, S.L.; Foster, C.A.

    1979-01-01

    We describe the design and operation of the solid hydrogen pellet injection system used in plasma refueling experiments on the ISX tokamak. The gun-type injector operates on the principle of gas dynamic acceleration of cold pellets confined laterally in a tube. The device is cooled by flowing liquid helium refrigerant, and pellets are formed in situ. Room temperature helium gas at moderate pressure is used as the propellant. The prototype device injected single hydrogen pellets into the tokamak discharge at a nominal 330 m/s. The tokamak plasma fuel content was observed to increase by (0.5--1.2) x 10 19 particles subsequent to pellet injection. A simple modification to the existing design has extended the performance to 1000 m/s. At higher propellant operating pressures (28 bars), the muzzle velocity is 20% less than predicted by an idealized constant area expansion process

  9. The ATLAS positive ion injector

    International Nuclear Information System (INIS)

    Shepard, K.W.; Bollinger, L.M.; Pardo, R.C.

    1990-01-01

    This paper reviews the design, construction status, and beam tests to date of the positive ion injector (PII) which is replacing the tandem injector for the ATLAS heavy-ion facility. PII consists of an ECR ion source on a 350 KV platform injecting a very low velocity superconducting linac. The linac is composed of an independently-phased array of superconducting four-gap interdigital resonators which accelerate over a velocity range of .006 to .05c. In finished form, PII will be able to inject ions as heavy as uranium into the existing ATLAS linac. Although at the present time little more than 50% of the linac is operational, the indenpently-phased array is sufficiently flexible that ions in the lower half of the periodic table can be accelerated and injected into ATLAS. Results of recent operational experience will be discussed. 5 refs

  10. ATA injector-gun calculations

    International Nuclear Information System (INIS)

    Paul, A.C.

    1981-01-01

    ATA is a pulsed, 50 ns 10 KA, 50 MeV linear induction electron accelerator at LLNL. The ETA could be used as an injector for ATA. However the possibility of building a new injector gun for ATA, raised the question as to what changes from the ETA gun in electrode dimensions or potentials, if any, should be considered. In this report the EBQ code results for the four electrode configurations are reviewed and an attempt is made to determine the geometrical scaling laws appropriate to these ETA type gun geometries. Comparison of these scaling laws will be made to ETA operation. The characteristic operating curves for these geometries will also be presented and the effect of washer position determined. It will be shown that emittance growth will impose a limitation on beam current for a given anode potential before the virtual cathode limit is reached

  11. The ATLAS positive ion injector

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Bollinger, L.M.; Pardo, R.C.

    1990-01-01

    This paper reviews the design, construction status, and beam tests to date of the positive ion injector (PII) which is replacing the tandem injector for the ATLAS heavy-ion facility. PII consists of an ECR ion source on a 350 KV platform injecting a very low velocity superconducting linac. The linac is composed of an independently-phased array of superconducting four-gap interdigital resonators which accelerate over a velocity range of .006 to .05c. In finished form, PII will be able to inject ions as heavy as uranium into the existing ATLAS linac. Although at the present time little more than 50% of the linac is operational, the indenpently-phased array is sufficiently flexible that ions in the lower half of the periodic table can be accelerated and injected into ATLAS. Results of recent operational experience will be discussed. 5 refs.

  12. Blood lead concentrations as a result of retained lead pellets in the craniomaxillofacial region in Benin City, Nigeria.

    Science.gov (United States)

    Edetanlen, B E; Saheeb, B D

    2016-06-01

    Patients who survive gunshot wounds often retain pellets in their bodies, which cause delayed morbidity from lead poisoning, and even death. Our aim was to find out whether there is a high concentration of lead in the blood of patients who have asymptomatic retention of lead pellets in the craniomaxillofacial region. We prospectively studied 28 patients who were admitted to our hospital with gunshot injuries to the region, and 28 control subjects. Each was originally recruited three days after injury. The control subjects were chosen from people who lived in the same household or worked in the same place as the patients. Any previous exposure to lead was excluded. Blood samples were collected three days and three months after injury and analysed for the presence of lead by atomic absorption spectrophotometry. The mean (SD) age for both patients and control subjects was 33 (12) years. The mean (SD) and range of concentrations of lead in patients three days after injury was 0.11 (0.07), range 0.01-0.32μmol/L, while those of the control subjects were 0.03 (0.02) and 0-0.06, respectively. Three months after injury, the mean (SD) and range of concentrations of the patients were 0.30 (0.11) and 0.12-0.59μmol/L, while those of the control subjects were 0-1.25 and 0.12 (0.006) μmol/L, respectively (p= 0.000). The study showed a higher mean blood lead concentration in patients with gunshot injuries than in control subjects, but lower than the threshold values published by the Centers for Disease Control/Occupational Health and Safety Administration in the United States. Copyright © 2016 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  13. Wood pellet seminar

    International Nuclear Information System (INIS)

    Aarniala, M.; Puhakka, A.

    2001-01-01

    The objective of the wood pellet seminar, arranged by OPET Finland and North Karelia Polytechnic, was to deliver information on wood pellets, pellet burners and boilers, heating systems and building, as well as on the activities of wood energy advisors. The first day of the seminar consisted of presentations of equipment and products, and of advisory desks for builders. The second day of the seminar consisted of presentations held by wood pellet experts. Pellet markets, the economy and production, the development of the pellet markets and their problems (in Austria), the economy of heating of real estates by different fuel alternatives, the production, delivery and marketing of wood pellets, the utilization of wood pellet in different utilization sites, the use of wood pellets in detached houses, pellet burners and fireplaces, and conversion of communal real estate houses to use wood pellets were discussed in the presentations. The presentations held in the third day discussed the utilization of wood pellets in power plants, the regional promotion of the production and the use of pellets. The seminar consisted also of visits to pellet manufacturing plant and two pellet burning heating plants

  14. Method of manufacturing nuclear fuel pellet

    International Nuclear Information System (INIS)

    Oguma, Masaomi; Masuda, Hiroshi; Hirai, Mutsumi; Tanabe, Isami; Yuda, Ryoichi.

    1989-01-01

    In a method of manufacturing nuclear fuel pellets by compression molding an oxide powder of nuclear fuel material followed by sintering, a metal nuclear material is mixed with an oxide powder of the nuclear fuel material. As the metal nuclear fuel material, whisker or wire-like fine wire or granules of metal uranium can be used effectively. As a result, a fuel pellet in which the metal nuclear fuel is disposed in a network-like manner can be obtained. The pellet shows a great effect of preventing thermal stress destruction of pellets upon increase of fuel rod power as compared with conventional pellets. Further, the metal nuclear fuel material acts as an oxygen getter to suppress the increase of O/M ratio of the pellets. Further, it is possible to reduce the swelling of pellet at high burn-up degree. (T.M.)

  15. A centrifuge CO2 pellet cleaning system

    International Nuclear Information System (INIS)

    Foster, C.A.; Fisher, P.W.; Nelson, W.D.; Schechter, D.E.

    1993-01-01

    Centrifuge-based cryogenic pellet accelerator technology, originally developed at Oak Ridge National Laboratory (ORNL) for the purpose of refueling fusion reactors with high-speed pellets of frozen deuterium/tritium,is now being developed as a method of cleaning without the use of conventional solvents. In these applications large quantities of pellets made of frozen CO 2 or argon are accelerated in a high-speed rotor. The accelerated pellet stream is used to clean or etch surfaces. The advantage of this system is that the spent pellets and debris resulting from the cleaning process can be filtered leaving only the debris for disposal. This paper discusses the centrifuge CO 2 pellet cleaning system, the physics model of the pellet impacting the surface, the centrifuge apparatus, and some initial cleaning and etching tests

  16. The pellet handbook: the production and thermal utilisation of pellets

    National Research Council Canada - National Science Library

    Obernberger, Ingwald; Thek, Gerold

    2010-01-01

    ...: - International overview of standards for pellets - Evaluation of raw materials and raw material potentials - Quality and properties of pellets - Technical evaluation of the pellet production process...

  17. Modelling the High-speed Injector for Diesel ICE

    Science.gov (United States)

    Buryuk, V. V.; Kayukov, S. S.; Gorshkalev, A. A.; Belousov, A. V.; Gallyamov, R. E.; Zvyagintsev, V. A.

    2018-01-01

    The article describes the results of research on the option of improving the operation speed of the electro-hydraulically driven injectors (Common Rail) for diesel ICE. The injector investigated in this article is a modified serial injector Common Rail-type with solenoid. The model and the injector parameters are represented in the package LMS Imagine. Lab AMESim with the detailed description of the substantiation and background for the research. Following the research results, the advantages of the proposed approach to analysing the operation speed were detected with outlining the direction of future studies.

  18. Steam-treated wood pellets: Environmental and financial implications relative to fossil fuels and conventional pellets for electricity generation

    International Nuclear Information System (INIS)

    McKechnie, Jon; Saville, Brad; MacLean, Heather L.

    2016-01-01

    Highlights: • Steam-treated pellets can greatly reduce greenhouse gas emissions relative to coal. • Cost advantage is seen relative to conventional pellets. • Higher pellet cost is more than balanced by reduced retrofit capital requirements. • Low capacity factors further favour steam-treated pellets over conventional pellets. - Abstract: Steam-treated pellets can help to address technical barriers that limit the uptake of pellets as a fuel for electricity generation, but there is limited understanding of the cost and environmental impacts of their production and use. This study investigates life cycle environmental (greenhouse gas (GHG) and air pollutant emissions) and financial implications of electricity generation from steam-treated pellets, including fuel cycle activities (biomass supply, pellet production, and combustion) and retrofit infrastructure to enable 100% pellet firing at a generating station that previously used coal. Models are informed by operating experience of pellet manufacturers and generating stations utilising coal, steam-treated and conventional pellets. Results are compared with conventional pellets and fossil fuels in a case study of electricity generation in northwestern Ontario, Canada. Steam-treated pellet production has similar GHG impacts to conventional pellets as their higher biomass feedstock requirement is balanced by reduced process electricity consumption. GHG reductions of more than 90% relative to coal and ∼85% relative to natural gas (excluding retrofit infrastructure) could be obtained with both pellet options. Pellets can also reduce fuel cycle air pollutant emissions relative to coal by 30% (NOx), 97% (SOx), and 75% (PM 10 ). Lesser retrofit requirements for steam-treated pellets more than compensate for marginally higher pellet production costs, resulting in lower electricity production cost compared to conventional pellets ($0.14/kW h vs. $0.16/kW h). Impacts of retrofit infrastructure become increasingly

  19. Trapping of pellet cloud radiation in thermonuclear plasmas

    International Nuclear Information System (INIS)

    Sergeev, V.Yu.; Miroshinikov, I.V.; Sudo, Shigeru; Namba, C.; Lisitsa, V.S.

    2001-01-01

    The experimental and theoretical data on radiation trapping in clouds of pellets injected into thermonuclear plasmas are presented. The theoretical modeling is performed in terms of equivalent Stark spectral line widths under condition of LTE (Sakha-Boltzman) in pellet cloud plasmas. It is shown that a domain of blackbody radiation could exist in hydrogen pellet clouds resulting in ''pellet disappearance'' effect which is absent in a case of impurity pellet clouds. Reasons for this difference are discussed. (author)

  20. Fuel pellet loading apparatus

    International Nuclear Information System (INIS)

    1980-01-01

    Apparatus is described for loading a predetermined amount of nuclear fuel pellets into nuclear fuel elements and particularly for the automatic loading of fuel pellets from within a sealed compartment. (author)

  1. The US pellet market

    International Nuclear Information System (INIS)

    Elliot, S.

    2007-01-01

    Bear Mountain is the largest producer of pellets, firelogs, animal beddings, and barbecue pellets in Western United States. The company's branded products are sold directly to more than 400 retail dealers. This presentation included a series of graphs depicting Bear Mountain's USA pellet sales in tons from 2002 to 2007; truckloads to various distribution areas; pellet stoves and insert units shipped from 1998 to 2006; and hearth appliance shipments from 1998 to 2006. It was noted that in the United States, 98 per cent of the pellets sold come in 40 pound bags and are delivered to retailers by truck. Space is needed for inventory purposes, as each customer may use 2 to 4 tons. The pellets are used in small ash capacity room heaters. The pellet producers buy sawdust from area mills. It was noted that the soft housing market combined with competition for pulp and paper has pinched the supply of pellets. Pellets were in short supply in the west coast during the winter of 2006-2007 and in eastern United States during the winters of 2004-2005 and 2005-2006, indicating that summer production of pellets is required in order to meet winter demand. The key demand factors for pellets include stove sales; pellet pricing; pricing of other fuels; and, weather. The key supply factors for pellets include availability of sawdust; logistics; competition; and cost. The greatest challenge facing pellet producers is the high cost of freight. It was concluded that 2008 will be another year of uncertainty for pellet producers, due to the abundant supply of pellets in the east and midwest, and stabilized alternative fuel pricing. tabs., figs

  2. Detailed Measurement of ORSC Main Chamber Injector Dynamics

    Science.gov (United States)

    Bedard, Michael J.

    Improving fidelity in simulation of combustion dynamics in rocket combustors requires an increase in experimental measurement fidelity for validation. In a model rocket combustor, a chemiluminescence based spectroscopy technique was used to capture flame light emissions for direct comparison to a computational simulation of the production of chemiluminescent species. The comparison indicated that high fidelity models of rocket combustors can predict spatio-temporal distribution of chemiluminescent species with trend-wise accuracy. The comparison also indicated the limited ability of OH* and CH* emission to indicate flame heat release. Based on initial spectroscopy experiments, a photomultiplier based chemiluminescence sensor was designed to increase the temporal resolution of flame emission measurements. To apply developed methodologies, an experiment was designed to investigate the flow and combustion dynamics associated with main chamber injector elements typical of the RD-170 rocket engine. A unique feature of the RD-170 injector element is the beveled expansion between the injector recess and combustion chamber. To investigate effects of this geometry, a scaling methodology was applied to increase the physical scale of a single injector element while maintaining traceability to the RD-170 design. Two injector configurations were tested, one including a beveled injector face and the other a flat injector face. This design enabled improved spatial resolution of pressure and light emission measurements densely arranged in the injector recess and near-injector region of the chamber. Experimental boundary conditions were designed to closely replicate boundary conditions in simulations. Experimental results showed that the beveled injector face had a damping effect on pressure fluctuations occurring near the longitudinal resonant acoustic modes of the chamber, implying a mechanism for improved overall combustion stability. Near the injector, the beveled geometry

  3. Deuterium pellet injection in the TFR Tokamak

    International Nuclear Information System (INIS)

    Lazare, O.

    1985-07-01

    Injecting fresh fuel deep inside the plasma of a thermonuclear reactor appears to be necessary; the only way to do that is to inject fast solid deuterium pellets. The existing theoretical, technical and experimental aspects of this method are presented. The experiments on TFR have confirmed that injecting pellets is technically feasible; a new kind of injector is presented. The injection does not degrade stability nor confinement of the plasma. The study of the transient phenomena occuring during the injection has proved to be an efficient way to investigate particles and energy transport in the discharge; in particular, a fast transport phenomenon, similar to those occuring during disruptions, has been studied in details. Conclusions about disruptions are drawn. (Ref 101) [fr

  4. Tritium pellet injection sequences for TFTR

    International Nuclear Information System (INIS)

    Houlberg, W.A.; Milora, S.L.; Attenberger, S.E.; Singer, C.E.; Schmidt, G.L.

    1983-01-01

    Tritium pellet injection into neutral deuterium, beam heated deuterium plasmas in the Tokamak Fusion Test Reactor (TFTR) is shown to be an attractive means of (1) minimizing tritium use per tritium discharge and over a sequence of tritium discharges; (2) greatly reducing the tritium load in the walls, limiters, getters, and cryopanels; (3) maintaining or improving instantaneous neutron production (Q); (4) reducing or eliminating deuterium-tritium (D-T) neutron production in non-optimized discharges; and (5) generally adding flexibility to the experimental sequences leading to optimal Q operation. Transport analyses of both compression and full-bore TFTR plasmas are used to support the above observations and to provide the basis for a proposed eight-pellet gas gun injector for the 1986 tritium experiments

  5. Linac pre-injector

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    New accelerating column of the linac pre-injector, supporting frame and pumping system. This new system uses two mercury diffusion pumps (in the centre) and forms part of the modifications intended to increase the intensity of the linac. View taken during assembly in the workshop.

  6. Methane pellet moderator development

    International Nuclear Information System (INIS)

    Foster, C.A.; Schechter, D.E.; Carpenter, J.M.

    2004-01-01

    A methane pellet moderator assembly consisting of a pelletizer, a helium cooled sub-cooling tunnel, a liquid helium cooled cryogenic pellet storage hopper and a 1.5L moderator cell has been constructed for the purpose demonstrating a system for use in high-power spallation sources. (orig.)

  7. Optimization of bentonite pellet properties

    International Nuclear Information System (INIS)

    Sanden, Torbjoern; Andersson, Linus; Jonsson, Esther; Fritzell, Anni

    2012-01-01

    . Fillings of extruded pellets have a higher flow resistance and decelerate the water front better which means that a larger part of the available voids will be used for water storing. A source of error observed is that the amount of fines in the pellet filling influences the results. The installation procedure includes blowing of pellets into the slots using equipment similar to what is used for shot-crete. Tests have shown that this procedure could create a lot of fines. Preparation of laboratory tests where this amount of fines is simulated will probably be very difficult since separation of the material starts as soon it has been collected and placed in a sack. A main conclusion is that large scale tests including the correct installation method will be necessary in order to fully understand the behaviour

  8. Geometrical dimensioning of PWR UO2 pellets

    International Nuclear Information System (INIS)

    Silva, A.T.

    1988-08-01

    The finite element structural program SAP-IV is used to calculate UO 2 pellet strains developed under thermal gradients in pressurized water reactors. The applied procedure allows to analyse the influence of various aspects of pelet geometry on cladding strains and can be utilized for the dimensioning of UO 2 pellets. Pellets purchased with flat ends, with dishes pressed into both ends, shouders, and a 45-deg edge chamfer are analysed. The analyse results are compared with experiemtnal data. (author) [pt

  9. Porosity influence on UO2 pellet fracture

    International Nuclear Information System (INIS)

    Quadros, N.F. de; Abreu Aires, M. de; Gentile, E.F.

    1976-01-01

    Compression tests were made with UO 2 pellets with grain size of 0,01 mm, approximately the same for all pellets, and with different porosities. The strain rate was 5,5 X 10 -5 sec -1 at room temperature. From fractographic studies and observations made during the compression tests, it was suggested that the pores and flaws resulting from sintering at 1650 0 C, play a fundamental role on the fracture mechanism of the UO 2 pellets [pt

  10. Neutron absorber pellets

    International Nuclear Information System (INIS)

    Radford, K.C.

    1983-01-01

    An annular burnable poison pellet of aluminium oxide - boron carbide (Al 2 O 3 - B 4 C) adapted for positioning in the annular space of concentrically disposed zircaloy tubes. Each tubular pellet is fabricated from Al 2 O 3 powders of moderate sintering activity which serves as a matrix for B 4 C medium size particle distribution. Special pellet moisture controls are incorporated in the pellet for moisture stability and the pellet is sintered in the temperature range of 1630 deg to 1650 deg C. This method of fabrication produces a pellet about 2 inch long with a wall thickness of from 0.020 inch to 0.040 inch. Fabricating each pellet to about 70% theoretical density gives an optimum compromise between fabricability, microstructure, strength and moisture absorption. (author)

  11. Modeling of classical swirl injector dynamics

    Science.gov (United States)

    Ismailov, Maksud M.

    The knowledge of the dynamics of a swirl injector is crucial in designing a stable liquid rocket engine. Since the swirl injector is a complex fluid flow device in itself, not much work has been conducted to describe its dynamics either analytically or by using computational fluid dynamics techniques. Even the experimental observation is limited up to date. Thus far, there exists an analytical linear theory by Bazarov [1], which is based on long-wave disturbances traveling on the free surface of the injector core. This theory does not account for variation of the nozzle reflection coefficient as a function of disturbance frequency, and yields a response function which is strongly dependent on the so called artificial viscosity factor. This causes an uncertainty in designing an injector for the given operational combustion instability frequencies in the rocket engine. In this work, the author has studied alternative techniques to describe the swirl injector response, both analytically and computationally. In the analytical part, by using the linear small perturbation analysis, the entire phenomenon of unsteady flow in swirl injectors is dissected into fundamental components, which are the phenomena of disturbance wave refraction and reflection, and vortex chamber resonance. This reveals the nature of flow instability and the driving factors leading to maximum injector response. In the computational part, by employing the nonlinear boundary element method (BEM), the author sets the boundary conditions such that they closely simulate those in the analytical part. The simulation results then show distinct peak responses at frequencies that are coincident with those resonant frequencies predicted in the analytical part. Moreover, a cold flow test of the injector related to this study also shows a clear growth of instability with its maximum amplitude at the first fundamental frequency predicted both by analytical methods and BEM. It shall be noted however that Bazarov

  12. SLC injector simulation and tuning for high charge transport

    International Nuclear Information System (INIS)

    Yeremian, A.D.; Miller, R.H.; Clendenin, J.E.; Early, R.A.; Ross, M.C.; Turner, J.L.; Wang, J.W.

    1992-08-01

    We have simulated the SLC injector from the thermionic gun through the first accelerating section and used the resulting parameters to tune the injector for optimum performance and high charge transport. Simulations are conducted using PARMELA, a three-dimensional ray-trace code with a two-dimensional space-charge model. The magnetic field profile due to the existing magnetic optics is calculated using POISSON, while SUPERFISH is used to calculate the space harmonics of the various bunchers and the accelerator cavities. The initial beam conditions in the PARMELA code are derived from the EGUN model of the gun. The resulting injector parameters from the PARMELA simulation are used to prescribe experimental settings of the injector components. The experimental results are in agreement with the results of the integrated injector model

  13. SLC injector simulation and tuning for high charge transport

    International Nuclear Information System (INIS)

    Yeremian, A.D.; Miller, R.H.; Clendenin, J.E.; Early, R.A.; Ross, M.C.; Turner, J.L.; Wang, J.W.

    1992-01-01

    We have simulated the SLC injector from the thermionic gun through the first accelerating section and used the resulting parameters to tune the injector for optimum performance and high charge transport. Simulations are conducted using PARMELA, a three-dimensional space-charge model. The magnetic field profile due to the existing magnetic optics is calculated using POISSON, while SUPERFISH is used to calculate the space harmonics of the various bunchers and the accelerator cavities. The initial beam conditions in the PARMELA code are derived from the EGUN model of the gun. The resulting injector parameters from the PARMELA simulation are used to prescribe experimental settings of the injector components. The experimental results are in agreement with the results of the integrated injector model. (Author) 5 figs., 7 refs

  14. Impurity pellet injection experiments at TFTR

    International Nuclear Information System (INIS)

    Marmar, E.S.

    1992-01-01

    Impurity (Li and C) pellet injection experiments on TFTR have produced a number of new and significant results. (1) We observe reproducible improvements of TFTR supershots after wall-conditioning by Li pellet injection ('lithiumization'). (2) We have made accurate measurements of the pitch angle profiles of the internal magnetic field using two novel techniques. The first measures the internal field pitch from the polarization angles of Li + line emission from the pellet ablation cloud, while the second measures the pitch angle profiles by observing the tilt of the cigar-shaped Li + emission region of the ablation cloud. (3) Extensive measurements of impurity pellet penetration into plasmas with central temperatures ranging from ∼0.3 to ∼7 keV have been made and compared with available theoretical models. Other aspects of pellet cloud physics have been investigated. (4) Using pellets as a well defined perturbation has allowed study of transport phenomena. In the case of small pellet perturbations, the characteristics of the background plasmas are probed, while with large pellets, pellet induced effects are clearly observed. These main results are discussed in more detail in this paper

  15. Carbon pellet cloud striations

    International Nuclear Information System (INIS)

    Parks, P.B.

    1989-01-01

    Fine scale striations, with alternating rows of bright and dark zones, have been observed in the ablation clouds of carbon pellets injected into the TEXT tokamak. The striations extend along the magnetic field for about 1 cm with quite regular cross-field variations characterized by a wavelength of a few mm. Their potential as a diagnostic tool for measuring q-profiles in tokamaks provides motivation for investigating the origin of the striations. The authors propose that the striations are not due to a sequence of high and low ablation rates because of the finite thermal magnetic islands localized at rational surfaces, q = m/n, would be responsible for reducing the electron flux to the pellet region; the length of the closed field line which forms the local magnetic axis of the island is too long to prevent a depletion of plasma electrons in a flux tube intercepting the pellet for the duration 2 rp / vp . Instead, they propose that striations are the manifestation of the saturated state of growing fluctuations inside the cloud. The instability is generated by E x B rotation of the ablation cloud. The outward centrifugal force points down the ablation density gradient inducing the Rayleigh-Taylor instability. The instability is not present for wave numbers along the field lines, which may explain why the striations are long and uniform in that direction. The E field develops inside the ablation cloud as a result of cold electron return currents which are induced to cancel the incoming hot plasma electron current streaming along the field lines

  16. Fermilab Main Injector plan

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1990-07-15

    The Fermilab Main Injector is the centrepiece of the 'Fermilab III' scheme to significantly upgrade the Laboratory's existing accelerator complex. The new accelerator is designed to provide increased particle beam levels to boost the collision rate in the Tevatron proton-antiproton collider (luminosity in excess of 5 x 10{sup 31} per sq cm per s) and, if approved, would provide increased flexibility in all areas of high energy physics research.

  17. Fermilab Main Injector plan

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The Fermilab Main Injector is the centrepiece of the 'Fermilab III' scheme to significantly upgrade the Laboratory's existing accelerator complex. The new accelerator is designed to provide increased particle beam levels to boost the collision rate in the Tevatron proton-antiproton collider (luminosity in excess of 5 x 10 31 per sq cm per s) and, if approved, would provide increased flexibility in all areas of high energy physics research

  18. ORNL pellet acceleration program

    International Nuclear Information System (INIS)

    Foster, C.A.; Milora, S.L.

    1978-01-01

    The Oak Ridge National Laboratory (ORNL) pellet fueling program is centered around developing equipment to accelerate large pellets of solidified hydrogen to high speeds. This equipment will be used to experimentally determine pellet-plasma interaction physics on contemporary tokamaks. The pellet experiments performed on the Oak Ridge Tokamak (ORMAK) indicated that much larger, faster pellets would be advantageous. In order to produce and accelerate pellets of the order of 1 to 6 mm in diameter, two apparatuses have been designed and are being constructed. The first will make H 2 pellets by extruding a filament of hydrogen and mechanically chopping it into pellets. The pellets formed will be mechanically accelerated with a high speed arbor to a speed of 950 m/sec. This technique may be extended to speeds up to 5000 m/sec, which makes it a prime candidate for a reactor fueling device. In the second technique, a hydrogen pellet will be formed, loaded into a miniature rifle, and accelerated by means of high pressure hydrogen gas. This technique should be capable of speeds of the order of 1000 m/sec. While this technique does not offer the high performance of the mechanical accelerator, its relative simplicity makes it attractive for near-term experiments

  19. Designing Liquid Rocket Engine Injectors for Performance, Stability, and Cost

    Science.gov (United States)

    Westra, Douglas G.; West, Jeffrey S.

    2014-01-01

    NASA is developing the Space Launch System (SLS) for crewed exploration missions beyond low Earth orbit. Marshall Space Flight Center (MSFC) is designing rocket engines for the SLS Advanced Booster (AB) concepts being developed to replace the Shuttle-derived solid rocket boosters. One AB concept uses large, Rocket-Propellant (RP)-fueled engines that pose significant design challenges. The injectors for these engines require high performance and stable operation while still meeting aggressive cost reduction goals for access to space. Historically, combustion stability problems have been a critical issue for such injector designs. Traditional, empirical injector design tools and methodologies, however, lack the ability to reliably predict complex injector dynamics that often lead to combustion stability. Reliance on these tools alone would likely result in an unaffordable test-fail-fix cycle for injector development. Recently at MSFC, a massively parallel computational fluid dynamics (CFD) program was successfully applied in the SLS AB injector design process. High-fidelity reacting flow simulations were conducted for both single-element and seven-element representations of the full-scale injector. Data from the CFD simulations was then used to significantly augment and improve the empirical design tools, resulting in a high-performance, stable injector design.

  20. FERMILAB: Main Injector

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The Fermilab Main Injector (FMI) project is the centerpiece of the Laboratory's Fermilab III programme for the 1990s. Designed to support a luminosity of at least 5x10 31 cm -2 s -1 in the Tevatron collider, it will also provide new capabilities for rare neutral kaon decay and neutrino oscillation studies. The Fermilab Main Injector 8-150 GeV synchrotron is designed to replace the existing Main Ring which seriously limits beam intensities for the Tevatron and the antiproton production target. The project has passed several significant milestones and is now proceeding rapidly towards construction. The project received a $11.65M appropriation in 1992 and has been given $15M for the current fiscal year. Through the Energy Systems Acquisition Advisory Board (ESAAB) process, the US Department of Energy (DoE) has authorized funds for construction of the underground enclosure and service building where the Main Injector will touch the Tevatron, and to the preparation of bids for remaining project construction

  1. FERMILAB: Main Injector

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1993-06-15

    The Fermilab Main Injector (FMI) project is the centerpiece of the Laboratory's Fermilab III programme for the 1990s. Designed to support a luminosity of at least 5x10{sup 31} cm{sup -2} s{sup -1} in the Tevatron collider, it will also provide new capabilities for rare neutral kaon decay and neutrino oscillation studies. The Fermilab Main Injector 8-150 GeV synchrotron is designed to replace the existing Main Ring which seriously limits beam intensities for the Tevatron and the antiproton production target. The project has passed several significant milestones and is now proceeding rapidly towards construction. The project received a $11.65M appropriation in 1992 and has been given $15M for the current fiscal year. Through the Energy Systems Acquisition Advisory Board (ESAAB) process, the US Department of Energy (DoE) has authorized funds for construction of the underground enclosure and service building where the Main Injector will touch the Tevatron, and to the preparation of bids for remaining project construction.

  2. Capabilities of nitrogen admixed cryogenic deuterium pellets

    Energy Technology Data Exchange (ETDEWEB)

    Sharov, Igor; Sergeev, Vladimir [SPU, Saint-Petersburg (Russian Federation); Lang, Peter; Ploeckl, Bernhard; Cavedon, Marco [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Kocsis, Gabor; Szepesi, Tamas [Wigner RCP RMI, Budapest (Hungary); Collaboration: ASDEX Upgrade Team

    2015-05-01

    Operation at high core density with high energy confinement - as foreseen in a future fusion reactor like DEMO - is being investigated at ASDEX Upgrade tokamak. The efficiency of pellet fuelling from the high-field side usually increases with increasing injection speed. Due to the fragile nature of the deuterium ice, however, the increment of pellet mass losses and subsequent pellet fragmentations take place when the speed is increased. Studies show, that admixing of a small amount of nitrogen (N{sub 2}) into D{sub 2} gas can be favorable for the mechanical stability of pellets. This might be helpful for deeper pellet penetration. Besides, seeding by N{sub 2} can enhance plasma performance due to both increasing the energy confinement time and reducing the divertor heat load in the envisaged ELMy H-mode plasma scenario. Fuelling efficiency of N{sub 2}-admixed solid D{sub 2} pellets and their nitrogen seeding capabilities were investigated. It was found that both the overall plasma density increase and the measured averaged pellet penetration depth were smaller in case of the admixed (1% mol. in the gas resulting in about 0.8% in the ice) pellet fuelling. Possibility of the N{sub 2}-seeding by admixed pellets was confirmed by CXRS measurements of N{sup 7+} content in plasma.

  3. Production and Innovative Applications of Cryogenic Solid Pellets

    International Nuclear Information System (INIS)

    Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Gouge, M.J.; Milora, S.L.

    1999-01-01

    For over two decades Oak Ridge National Laboratory has been developing cryogenic pellet injectors for fueling hot, magnetic fusion plasmas. Cryogenic solid pellets of all three hydrogen isotopes have been produced in a size range of 1- to 10-mm diameter and accelerated to speeds from <100 to ∼3000 m/s. The pellets have been formed discretely by cryocondensation in gun barrels and also by extrusion of cryogenic solids at mass flow rates up to ∼0.26 g/s and production rates up to ten pellets per second. The pellets traverse the hot plasma in a fraction of a millisecond and continuously ablate, providing fresh hydrogenic fuel to the interior of the plasma. From this initial application, uses of this technology have expanded to include (1) cryogenic xenon drops or solids for use as a debris-less target in a laser plasma source of X-rays for advanced lithography systems, (2) solid argon and carbon dioxide pellets for surface cleaning or decontamination, and (3) methane pellets in a liquid hydrogen bath for use as an innovative moderator of cold neutrons. Methods of production and acceleration/transport of these cryogenic solids will be described, and examples will be given of their use in prototype systems

  4. Wood pellets for stoker burner

    International Nuclear Information System (INIS)

    Nykaenen, S.

    2000-01-01

    The author of this article has had a stoker for several years. Wood chips and sod peat has been used as fuels in the stoker, either separately or mixed. Last winter there occurred problems with the sod peat due to poor quality. Wood pellets, delivered by Vapo Oy were tested in the stoker. The price of the pellets seemed to be a little high 400 FIM/500 kg large sack. If the sack is returned in good condition 50 FIM deposit will be repaid to the customer. However, Vapo Oy informed that the calorific value of wood pellets is three times higher than that of sod peat so it should not be more expensive than sod peat. When testing the wood pellets in the stoker, the silo of the stoker was filled with wood pellets. The adjustments were first left to position used for sod peat. However, after the fire had ignited well, the adjustments had to be decreased. The content of the silo was combusted totally. The combustion of the content of the 400 litter silo took 4 days and 22 hours. Respectively combustion of 400 l silo of good quality sod peat took 2 days. The water temperature with wood pellets remained at 80 deg C, while with sod peat it dropped to 70 deg C. The main disadvantage of peat with small loads is the unhomogenous composition of the peat. The results of this test showed that wood pellets will give better efficiency than peat, especially when using small burner heads. The utilization of them is easier, and the amount of ash formed in combustion is significantly smaller than with peat. Wood pellets are always homogenous and dry if you do not spoil it with unproper storage. Pellets do not require large storages, the storage volume needed being less than a half of the volume needed for sod peat. When using large sacks the amount needed can even be transported at the trunk of a passenger car. Depending on the area to be heated, a large sack is sufficient for heating for 2-3 weeks. Filling of stoker every 2-5 day is not an enormous task

  5. NLC electron injector beam dynamics

    International Nuclear Information System (INIS)

    Yeremian, A.D.; Miller, R.H.

    1995-10-01

    The Next Linear Collider (NLC) being designed at SLAC requires a train of 90 electron bunches 1.4 ns apart at 120 Hz. The intensity and emittance required at the interaction point, and the various machine systems between the injector and the IP determine the beam requirements from the injector. The style of injector chosen for the NLC is driven by the fact that the production of polarized electrons at the IP is a must. Based on the successful operation of the SLC polarized electron source a similar type of injector with a DC gun and subharmonic bunching system is chosen for the NLC

  6. CO2 pellet blasting studies

    International Nuclear Information System (INIS)

    Archibald, K.E.

    1997-01-01

    Initial tests with CO 2 pellet blasting as a decontamination technique were completed in 1993 at the Idaho Chemical Processing Plant (ICPP) at the Idaho National Engineering Laboratory (INEL). During 1996, a number of additional CO 2 pellet blasting studies with Alpheus Cleaning Technologies, Oak Ridge National Laboratory, and Pennsylvania State University were conducted. After the testing with Alpheus was complete, an SDI-5 shaved CO 2 blasting unit was purchased by the ICPP to test and determine its capabilities before using in ICPP decontamination efforts. Results of the 1996 testing will be presented in this report

  7. Injector machine development days 2017

    CERN Document Server

    Bartosik, H

    2017-01-01

    Following the important progress made in 2016 in the Machine Development (MD) activities that took place in all the accelerators of the LHC injector chain, the days 23-24 March, 2017, have been devoted to summarise the main out- come from the MDs and lay out the plans for the next steps. The event was also triggered by the following motivations and goals: Give a chance to the MD users to present their results; Provide a platform in which MD users, MD coordinators and operations crews meet and discuss openly the optimisation of the MD time and procedures, taking into account of the different perspectives; Provide an overview of all the ongoing activities to better frame their impact in the broader picture of the CERN short and long term projects; Identify the open questions, define and prioritise ma- chine studies in the injectors for 2017; Create the opportunity to obtain and document written reports from MD users. Within this contribution, we just summarise the context and the main points discussed at the ev...

  8. Commissioning of the 123 MeV injector for 12 GeV CEBAF

    International Nuclear Information System (INIS)

    Wang, Yan; Hofler, Alicia S.; Kazimi, Reza

    2015-09-01

    The upgrade of CEBAF to 12GeV included modifications to the injector portion of the accelerator. These changes included the doubling of the injection energy and relocation of the final transport elements to accommodate changes in the CEBAF recirculation arcs. This paper will describe the design changes and the modelling of the new 12GeV CEBAF injector. Stray magnetic fields have been a known issue for the 6 GeV CEBAF injector, the results of modelling the new 12GeV injector and the resulting changes implemented to mitigate this issue are described in this paper. The results of beam commissioning of the injector are also presented.

  9. Fuel pellet fracture and relocation

    International Nuclear Information System (INIS)

    Walton, L.A.; Husser, D.L.

    1983-01-01

    The model used to describe fuel pellet fracture and relocation is an important feature of a fuel performance computer code. This model becomes especially important if the computer code is principally to be used for the evaluation of pellet clad interaction. The fracture and relocation model being developed for the B and W fuel performance code FUMAC was derived from an extensive data base. Cross sections of irradiated fuel rods were photographically magnified and measured to determine the configuration of the fragments of the fractured fuel pellets. Data, representing a wide range of LWR fuel designs and as-manufactured mechanical configurations, were catalogued and systematically reduced and then correlated as a function of the likely independent variables. These correlations define the key phenomenological behavior patterns which the relocation model must duplicate and indicate which mechanistic approaches are viable explanations of this behavior. The data base covers the burnup range from approximately one to 35 GWd/mtU and linear heat rates from less than 100 to nearly 700 W/Cm. This paper presents the correlated data base and the methods used to derive and interpret it. It was determined from this data base that pellet cracking is initially both power level and burnup dependent but tends to saturate eventually with continued steady irradiation. Fuel pellet relocation was found to be much more extensive than would be deduced from thermal considerations alone. Even at very low burnups fuel fragments were found to move outward until restrained by the cladding. The results also suggest that changes in internal resistance to heat flow within the pellets due to the opening of cracks may be as important as peripheral gap changes to the thermal modeler. The transient response and thermal implications of this model are recommended as primary areas for future investigation

  10. Injection of pellets into the TCA tokamak

    International Nuclear Information System (INIS)

    Martin, Y.

    1993-05-01

    This thesis presents experimental results from the analysis of the ablation process of pellets injected into the TCA tokamak. The determination of scaling laws relating the pellet penetration to the pellet and plasma parameters preceding injection, were used to improve the understanding of the interaction of the pellet with the plasma since a) the pellet and plasma conditions preceding injection were varied over a large range, and b) the estimation of the penetration depth takes into account the influence of striations in the deposition profile. Over 400 pellets with a range of sizes and speeds were injected into a range of plasma parameters in order to create a database from which the scaling laws could be deduced. The ablation characteristics were principally measured with two CCD video cameras, which provided good spatial resolution, and two filtered photomultiplier tubes, which provided good temporal resolution of the light emitted from the pellet ablation cloud. In the text, the traditional methods of analysing these diagnostics are examined with special reference to the presumptions that a) the pellet velocity is constant in the plasma, and b) the light intensity determined from the ablation cloud is proportional to the ablation rate. After successive data reduction from the database, in order to separate the effects of varying different parameters, the main observations were that, a) the pellet penetration varies as the square root of the pellet velocity, b) the scaling laws for the other parameters strongly depend on whether the pellet has sufficient velocity to reach the q=1 rational magnetic surface in the tokamak. (author) 45 refs

  11. Developing the Model of Fuel Injection Process Efficiency Analysis for Injector for Diesel Engines

    Science.gov (United States)

    Anisimov, M. Yu; Kayukov, S. S.; Gorshkalev, A. A.; Belousov, A. V.; Gallyamov, R. E.; Lysenko, Yu D.

    2018-01-01

    The article proposes an assessment option for analysing the quality of fuel injection by the injector constituting the development of calculation blocks in a common injector model within LMS Imagine.Lab AMESim. The parameters of the injector model in the article correspond to the serial injector Common Rail-type with solenoid. The possibilities of this approach are demonstrated with providing the results using the example of modelling the modified injector. Following the research results, the advantages of the proposed approach to analysing assessing the fuel injection quality were detected.

  12. The NLC Injector System

    International Nuclear Information System (INIS)

    Bharadwaj, V.; Clendenin, J.E.; Emma, P.; Frisch, J.; Jobe, R.; Kotseroglou, T.; Krejcik, P.; Kulikov, A.V.; Li, Z.; Maruyama, T.; Millage, K.K.; McKee, B.; Mulhollan, G.; Munro, M.H.; Rago, C.E.; Raubenheimer, T.O.; Ross, M.C.; Phinney, N.; Schultz, D.C.; Sheppard, J.C.; Spencer, C.M.; Vlieks, A.E.; Woodley, M D.; Bibber, K. van; Takeda, S.

    1999-01-01

    The Next Linear Collider (NW) Injector System is designed to produce low emittance, 10 GeV electron and positron beams at 120 hertz for injection into the NLC main linacs. Each beam consists of a train of 9.5 bunches spaced by 2.8 ns; each bunch has a population of 1.15 x 10 10 particles. At injection into the main linacs, the horizontal and vertical emittances are specified to be γ var e psilon x = 3 x 10 -6 m-rad and γ var e psilon

  13. Reciprocating pellet press

    Science.gov (United States)

    Jones, Charles W.

    1981-04-07

    A machine for pressing loose powder into pellets using a series of reciprocating motions has an interchangeable punch and die as its only accurately machines parts. The machine reciprocates horizontally between powder receiving and pressing positions. It reciprocates vertically to press, strip and release a pellet.

  14. SAF line pellet gaging

    International Nuclear Information System (INIS)

    Jedlovec, D.R.; Bowen, W.W.; Brown, R.L.

    1983-10-01

    Automated and remotely controlled pellet inspection operations will be utilized in the Secure Automated Fabrication (SAF) line. A prototypic pellet gage was designed and tested to verify conformance to the functions and requirements for measurement of diameter, surface flaws and weight-per-unit length

  15. Present status of laser fusion fuel pellet

    International Nuclear Information System (INIS)

    Nakai, Sadao; Mima, Kunioki; Norimatsu, Takayoshi; Takagi, Masaru.

    1986-01-01

    Accompanying the advance of pellet implosion experiment, the data base required for fuel pellet design has been steadily accumulated. The clarification of the physics related to the process of absorbing laser beam, energy transport, the generation of ablative pressure, the hydrodynamic mechanism of implosion, the energy transmission to fuel core and so on progressed, and the design data supported by these results are prepared. Based on the data base like this, the design of fuel pellets taking the optimization of implosion in consideration is carried out. The various fuel pellets designed in this way are tested for their effectiveness by implosion experiment. For this purpose, the high performance measurement of implosion and the high accuracy manufacture of fuel pellets become very important. In this paper, the present state of the research on the method of laser implosion, the example of pellet design and the law of proportion, the manufacturing techniques of the fuel pellets having various structures, the techniques dealing with tritium and so on is summarized, and the direction of future research and development is ascertained. At present, implosion experiment is carried out mostly by hanging a pellet target with a fiber of several μm diameter, but the fiber impairs the symmetry of implosion. The levitation techniques without contact is required. (Kako, I.)

  16. Emissions from burning of softwood pellets

    International Nuclear Information System (INIS)

    Olsson, Maria; Kjaellstrand, Jennica

    2004-01-01

    Softwood pellets from three different Swedish manufacturers were burnt in laboratory scale to determine compounds emitted. The emissions were sampled on Tenax cartridges and assessed by gas chromatography and mass spectrometry. No large differences in the emissions from pellets from different manufacturers were observed. The major primary semi-volatile compounds released during flaming burning were 2-methoxyphenols from lignin. The methoxyphenols are of interest due to their antioxidant effect, which may counteract health hazards of aromatic hydrocarbons. Glowing combustion released the carcinogenic benzene as the predominant aromatic compound. However, the benzene emissions were lower than from flaming burning. To relate the results from the laboratory burnings to emissions from pellet burners and pellet stoves, chimney emissions were determined for different burning equipments. The pellet burner emitted benzene as the major aromatic compound, whereas the stove and boiler emitted phenolic antioxidants together with benzene. As the demand for pellets increases, different biomass wastes will be considered as raw materials. Ecological aspects and pollution hazards indicate that wood pellets should be used primarily for residential heating, whereas controlled large-scale combustion should be preferred for pellets made of most other types of biomass waste. (Author)

  17. Geometric dimensioning of UO2 pellets for PWR

    International Nuclear Information System (INIS)

    Teixeira e Silva, A.

    1988-01-01

    The finite element structural program SAP-IV is used to calculate UO 2 pellet strains developed under thermal gradients in pressurized water reactors. The applied procedure allows to analyse the influence of various aspects of pellet geometry on cladding strains and can be utilized for the dimensioning of UO 2 pellets. Pellets purchased with flat ends, with dishes pressed into both ends, shouders, and a 45-deg edge chamfer are analysed. The analyse results are compared with experimental data.(autor) [pt

  18. Acceleration of solid pellets using a plasma gun

    International Nuclear Information System (INIS)

    Buller, T.L.; Turnbull, R.J.; Kim, K.

    1979-01-01

    The use of solid pellets of hydrogen isotopes to refuel thermonuclear fusion reactors based on the tokamak configuration will require that the pellets be accelerated to high velocities. One possible method of acceleration is to interact a fast plasma from a plasma gun with the pellets. In this paper preliminary results are given on the acceleration of solid pellets with a plasma gun. The plasma-gun requirements for successful acceleration to high velocities are discussed

  19. On the Drag Effect of a Refuelling Pellet

    DEFF Research Database (Denmark)

    Chang, Tinghong; Michelsen, Poul

    1981-01-01

    A refueling pellet is subjected mainly to two kinds of drags: (1) inertial drag caused by the motion of the pellet relative to the surrounding plasma, and (2) ablation drag caused by an uneven ablation rate of the front and the rear surface of the pellet in an inhomogeneous plasma. Computational ...... results showed that for reasonable combinations of pellet size and injection speed, the drag effect is hardly detectable for plasma conditions prevailing in current large tokamaks....

  20. Structure change of fuel pellets

    International Nuclear Information System (INIS)

    Imanaka, Tetsuji

    1980-01-01

    The investigation of the broken pieces of fuel rods in Mihama No. 1 reactor was carried out in the Japan Atomic Energy Research Institute, and unexpectedly led to the post-irradiation tests. The investigation group of the Kyoto University Research Institute considers that the pursuit of the causes of accident by the government was insufficient, and the countermeasures are problematical, as the result of having examined various reports. In this study, the white foreign phase and swelling of cladding tubes were investigated, because these are especially important in view of the soundness of the fuel. Besides, the possibility of the oxidation of UO 2 pellets by cooling water was examined. It was found by metallographic test that the featuring phase different from UO 2 structure existed in the central part of pellets remaining in two broken fuel rod pieces. The report of JAERI judged that it is the product of solid phase reaction above a certain threshold temperature. The change of pellet structure observed in the white foreign phase and the swell of a cladding tube was caused by the oxidation of UO 2 pellets by primary coolant. The result of observation of the white foreign phase showed that it had been liquid phase at the time of the formation. From the thermodynamic examination based on oxygen potential, UO 2 is oxidized above 1100 deg C in the atmosphere of primary coolant. The liquid phase of the oxidized phase of UO 2 is formed above 1600 deg C. (Kako, I.)

  1. Effect of injector geometry on the performance of an internally mixed liquid atomizer

    Energy Technology Data Exchange (ETDEWEB)

    Kushari, A.

    2010-11-15

    This paper presents the results of an experimental study of the effect of injector's geometry on the performance of an internally mixed, air-assisted, liquid injector. In this type of injector a small amount of air is injected into a liquid stream within the injector. The interaction of the liquid with the atomizing air inside the injector induces atomization. The results presented in this paper show that the size of the droplets produced by the investigated injector decreases with a decrease in the air injection area. This is due to the increase in atomizing air injection velocity that accompanies the decrease in the air injection area, which improves atomization. This study also shows that the droplet sizes decrease with an increase in the injector's length, which is attributed to the increase in total interactive force. (author)

  2. Behaviour of fission gas in the rim region of high burn-up UO2 fuel pellets with particular reference to results from an XRF investigation

    International Nuclear Information System (INIS)

    Mogensen, M.; Walker, C.T.

    1999-01-01

    XRF and EPMA results for retained xenon from Battelle's high burn-up effects program are re-evaluated. The data reviewed are from commercial low enriched BWR fuel with burn-ups of 44.8-54.9 GWd/tU and high enriched PWR fuel with burn-ups from 62.5 to 83.1 GWd/tU. It is found that the high burn-up structure penetrated much deeper than initially reported. The local burn-up threshold for the formation of the high burn-up structure in those fuels with grain sizes in the normal range lay between 60 and 75 GWd/tU. The high burn-up structure was not detected by EPMA in a fuel that had a grain size of 78 μm although the local burn-up at the pellet rim had exceeded 80 GWd/tU. It is concluded that fission gas had been released from the high burn-up structure in three PWR fuel sections with burn-ups of 70.4, 72.2 and 83.1 GWd/tU. In the rim region of the last two sections at the locations where XRF indicated gas release the local burn-up was higher than 75 GWd/tU. (orig.)

  3. Statistical analysis and modeling of pelletized cultivation of Mucor circinelloides for microbial lipid accumulation.

    Science.gov (United States)

    Xia, Chunjie; Wei, Wei; Hu, Bo

    2014-04-01

    Microbial oil accumulation via oleaginous fungi has some potential benefits because filamentous fungi can form pellets during cell growth and these pellets are easier to harvest from the culture broth than individual cells. This research studied the effect of various culture conditions on the pelletized cell growth of Mucor circinelloides and its lipid accumulation. The results showed that cell pelletization was positively correlated to biomass accumulation; however, pellet size was negatively correlated to the oil content of the fungal biomass, possibly due to the mass transfer barriers generated by the pellet structure. How to control the size of the pellet is the key to the success of the pelletized microbial oil accumulation process.

  4. Conceptual design of pellet charge eXchange (PCX) diagnostics for stellarator W7-X

    International Nuclear Information System (INIS)

    Sergeev, Y.Yu; Kuteev, B.V.; Bakhareva, O.A.; Kostrukov, A.Y.; Skokov, V.G.; Petrov, M.P.; Kislyakov, A.I.; Burhenn, R.; Kick, M.

    2002-01-01

    Pellet Charge eXchange diagnostic using Li pellets has been considered for the W7-X machine. Geometry of the experimental set-up and parameters of both lithium pellet injector (LPI) and neutral particle analyser (NPA) were evaluated. It was shown that this diagnostics can provide very well detectable H 0 signal in the range 50 - 1000 keV generated by RF driven H + minority ions in W7-X. The PCX diagnostics will be able to measure H + energy spectra and density profiles in wide range of W7-X plasma parameters. The proposed NPA can be designed on a basis of the NPA ISEP (Ioffe institute) installed now on JET. A pellet light-gas gun can be used to accelerate Li pellets of 2 - 3 mm in size up to 1 km/s velocities. That provides the required pellet penetration into the plasma core. Due to sticky problems with Li operation, a special technique of loading and keeping the pellets in a charger unit of LPI has to be developed. Development of PCX diagnostics for absolute measurements of the confined minority protons requires improvement of the pellet ablation model used. Knowledge of the cloud dimensions and density distributions of different charge states of ions is of special interest. It is necessary to improve predictions of pellet penetrations in non-Maxwellian plasmas as well. An optical system for measurements of pellet cloud density profiles should be foreseen on W7-X. (orig.)

  5. Simulation of transient effects in the heavy ion fusion injectors

    International Nuclear Information System (INIS)

    Chen, Y.J.; Hewett, D.

    1993-01-01

    The authors have used the 2-D PIC code, GYMNOS, to study the transient behaviors in the Heavy Ion Fusion (HIF) injectors. GYMNOS simulations accurately provide the steady state Child-Langmuir current and the beam transient behavior within a planar diode. The simulations of the LBL HIF ESAC injector experiments agree well with the experimental data and EGUN steady state results. Simulations of the nominal HIF injectors have revealed the need to design the accelerating electrodes carefully to control the ion beam current, particularly the ion loss at the end of the bunch as the extraction voltage is reduced

  6. Simulation of transient effects in the heavy ion fusion injectors

    Science.gov (United States)

    Chen, Yu-Jiuan; Hewett, D. W.

    1993-05-01

    We have used the 2-D PIC code, GYMNOS, to study the transient behaviors in the Heavy Ion Fusion (HIF) injectors. GYMNOS simulations accurately provide the steady state Child-Langmuir current and the beam transient behavior within a planar diode. The simulations of the LBL HIF ESAC injector experiments agree well with the experimental data and EGUN steady state results. Simulations of the nominal HIF injectors have revealed the need to design the accelerating electrodes carefully to control the ion beam current, particularly the ion loss at the end of the bunch as the extraction voltage is reduced.

  7. Injector of the Utrecht EN tandem

    Energy Technology Data Exchange (ETDEWEB)

    Borg, K. van der; Haas, A.P. de; Hoogenboom, A.M.; Strasters, B.A.; Vermeer, A.; Zwol, N.A. van (Rijksuniversiteit Utrecht (Netherlands). Fysisch Lab.)

    1984-02-15

    An injector has been built to obtain improved beam transmission through the EN tandem. The injector has been provided with a 90/sup 0/ analysing magnet, m/..delta..m=300, and 130 kV preacceleration. Beam optics calculations have been made for the injector and tandem. The injector has been equipped with a fiber optics control and data acquisition system.

  8. The injector of the Utrecht EN tandem

    International Nuclear Information System (INIS)

    Borg, K. van der; Haas, A.P. de; Hoogenboom, A.M.; Strasters, B.A.; Vermeer, A.; Zwol, N.A. van

    1984-01-01

    An injector has been built to obtain improved beam transmission through the EN tandem. The injector has been provided with a 90 0 analysing magnet, m/Δm=300, and 130 kV preacceleration. Beam optics calculations have been made for the injector and tandem. The injector has been equipped with a fiber optics control and data acquisition system. (orig.)

  9. High-brightness electron injectors

    International Nuclear Information System (INIS)

    Sheffield, R.L.

    1987-01-01

    Free-electron laser (FEL) oscillators and synchrotron light sources require pulse trains of high peak brightness and, in some applications, high-average power. Recent developments in the technology of photoemissive and thermionic electron sources in rf cavities for electron-linac injector applications offer promising advances over conventional electron injectors. Reduced emittance growth in high peak-current electron injectors may be achieved by using high field strengths and by linearizing the radial component of the cavity electric field at the expense of lower shunt impedance

  10. Parallel expansion of the ablation cloud during pellet injection in Tore Supra

    International Nuclear Information System (INIS)

    Pegourie, B.; Bruneau, J.L.; Picchiottino, J.M.

    1991-01-01

    The ablated matter propagation along the field lines during pellet ablation is observed with a five chords interferometer toroidally located at -π/3 of the pellet injector. The time resolution is 16μs and the sensitivity better than 3 10 17 m -2 . The beginning of the fast acquisition is triggered by the pellet itself and its maximum duration is 20ms. About 500μs after the pellet enters the discharge, the experimental signals exhibit a steep increase. Excepted in a few cases for which a strong oscillation at a typical frequency of 0.5kHz was detected during several ms, a new quasi-steady state is reached after about lms. The importance of the measured perturbation and the details of the sequence described above depends, for each chord, on both the Q profile and pellet penetration

  11. Particle density determination of pellets and briquettes

    Energy Technology Data Exchange (ETDEWEB)

    Rabier, Fabienne; Temmerman, Michaeel [Centre wallon de Recherches agronomiques, Departement de Genie rural, CRA-W, Chaussee de Namur, 146, B 5030 Gembloux (Belgium); Boehm, Thorsten; Hartmann, Hans [Technologie und Foerderzentrum fuer Nachwachsende Rohstoffe, TFZ, Schulgasse 18, D 94315 Straubing (Germany); Daugbjerg Jensen, Peter [Forest and Landscape, The Royal Veterinary and Agricultural University, Rolighedsvej 23, DK 1958 Frederiksberg C (Denmark); Rathbauer, Josef [Bundesanstalt fuer Landtechnik, BLT, Rottenhauer Strasse,1 A 3250 Wieselburg (Austria); Carrasco, Juan; Fernandez, Miguel [Centro de investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Avenida Complutense, 22 E 28040 Madrid (Spain)

    2006-11-15

    Several methods and procedures for the determination of particle density of pellets and briquettes were tested and evaluated. Round robin trials were organized involving five European laboratories, which measured the particle densities of 15 pellet and five briquette types. The test included stereometric methods, methods based on liquid displacement (hydrostatic and buoyancy) applying different procedures and one method based on solid displacement. From the results for both pellets and briquettes, it became clear that the application of a method based on either liquid or solid displacement (only tested on pellet samples) leads to an improved reproducibility compared to a stereometric method. For both, pellets and briquettes, the variability of measurements strongly depends on the fuel type itself. For briquettes, the three methods tested based on liquid displacement lead to similar results. A coating of the samples with paraffin did not improve the repeatability and the reproducibility. Determinations with pellets proved to be most reliable when the buoyancy method was applied using a wetting agent to reduce surface tensions without sample coating. This method gave the best values for repeatability and reproducibility, thus less replications are required to reach a given accuracy level. For wood pellets, the method based on solid displacement gave better values of repeatability, however, this instrument was tested at only one laboratory. (author)

  12. Fundamentals of Biomass pellet production

    DEFF Research Database (Denmark)

    Holm, Jens Kai; Henriksen, Ulrik Birk; Hustad, Johan Einar

    2005-01-01

    Pelletizing experiments along with modelling of the pelletizing process have been carried out with the aim of understanding the fundamental physico-chemical mechanisms that control the quality and durability of biomass pellets. A small-scale California pellet mill (25 kg/h) located with the Biomass...

  13. Mox pellet reference material

    International Nuclear Information System (INIS)

    Perolat, J.P.

    1991-01-01

    A first batch of MOX pellets certified in plutonium and uranium has been prepared and characterised in France to meet the needs of laboratories which are engaged upon destructive analysis for safeguards purposes especially in fuel fabrication plants. The pellets sintering has been obtained in a special fabrication to achieve an homogeneity better than 0.1%. The plutonium and uranium characterisation by chemical analysis has been carried out by two laboratories using at least two different methods. 1 fig., 5 refs

  14. Optimization of backfill pellet properties AASKAR DP2 - Laboratory tests

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Linus; Sanden, Torbjoern [Clay Technology AB, Lund (Sweden)

    2012-12-15

    's ability to buffer the inflowing groundwater during the installation phase was investigated in two types of tests. In the first test the wetting behavior was observed at small scale in a Plexiglas tube. The second test was performed in an artificial pellet slot with Plexiglas sides. The ASHA extruded 6 mm pellet seem to be the superior in water storing capacity, though it is suggested that this result may be more related to the presence of a fine grained material within the pellet mass than the pellets themselves. 4. Installation test. The pellets will most likely be installed with a shotcrete machine blowing them into place. This method was tested at full scale in order to investigate how much of the pellet filling that would be crushed into fine grained material if there is no water used during their placement. ASHA extruded 6 mm was the most durable pellet type with 5% of the material being crushed. 7 - 8% of the IBECO extruded pellet types (6 and 10 mm) were crushed into finer grains. The least durable pellets were the ASHA compacted pellets (pillow and almond shaped) with a crushing ratio of 53 to 61%. These results may have significance in terms of subsequent water uptake behavior. Large scale tests at repository-scale still need to be done utilizing shotcrete equipment so that more experience is obtained in how to control the installation of the pellet filling and identify the key influences on its composition and as-placed condition.

  15. Pellet transfer apparatus and method

    International Nuclear Information System (INIS)

    DiGrande, J.T.; Huggins, T.B. Sr.; Lambert, D.V.; Roberts, E.

    1991-01-01

    This patent describes a pellet inspection system having a station for inspecting a predetermined parameter of a pellet. It comprises means for aligning and guiding pellets in a first row to be advanced along a linear path past the pellet inspecting station and in a second row previously advanced along the linear path past the pellet inspecting station; and a transfer mechanism operable for engaging at least one of the pellets in each of the first and second rows and moving from an initial position through a forward stroke to advance the first and second rows of pellets along the liner path such that the inspecting station can inspect the preselected parameter of the pellets in the first row as they are advanced successively , the transfer mechanism being operable for disengaging the pellets and moving through a return stroke relative to the stationary advanced first and second rows of pellets back to the initial position

  16. Nuclear fuel pellet inspection system

    International Nuclear Information System (INIS)

    Ahmed, H.J.; Beatty, J.M.; Kugler, R.W.

    1992-01-01

    At least one axially extending linear portion of the peripheral surface of the pellet is optically sensed, a set of digital values representative of the pellet surface is generated, and the set is compared to a predetermined standard. Groups of adjacent locations on the surface of the pellet having values greater or less than the predetermined standard are identified, and the pellet is rejected, when a flawed area exceeds a predetermined size. During inspection, the pellet is moved axially through an inspection station by parallel support rolls, spaced by a distance less than the pellet diameter. The rolls are rotated upward and outward from each other, rotating the pellet, and chain dogs are positioned between the spaced rolls for engaging a pellet and moving it along the rolls. The pellet is rejected if its peripheral surface area is too great, and a reference pellet may be used. (author)

  17. Impurity pellet injection experiments at TFTR

    International Nuclear Information System (INIS)

    Marmar, E.S.

    1991-01-01

    Impurity (Li and C) pellet experiments, which began at TFTR in 1989, and are expected to continue at least through 1991, have continued to produce new and significant results. The most significant of these are: (1) improvements in TFTR supershots after wall-conditioning by Li pellet injection; (2) accurate measurements of the pitch angle profiles of the internal magnetic field using the polarization angles of line emission from Li + in the pellet ablation cloud; and (3) initial measurements of pitch angle profiles using the tilt of the LI + emission region of the ablation cloud which is stretched out along the field lines

  18. Neutron and hard x-ray measurements during pellet deposition in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Heidbrink, W.W.; Milora, S.L.; Schmidt, G.L.; Schneider, W.; Ramsey, A.

    1986-06-01

    Measurements of neutrons and hard x rays are made with a pair of plastic scintillators during injection of deuterium pellets into deuterium TFTR plasmas. Three cases are investigated. During ohmic heating in plasmas with few runaway electrons, the neutron emission does not increase when a pellet is injected, indicating that strong acceleration of the pellet ions does not occur. In ohmic plasmas with low but detectable levels of runaway electrons, an x-ray burst is observed on a detector near the pellet injector as the pellet ablates, while a detector displaced 126/sup 0/ toroidally from the injector does not measure a synchronous burst. Reduced pellet penetration correlates with the presence of x-ray emission, suggesting that the origin of the burst is bremsstrahlung from runaway electrons that strike the solid pellet. In deuterium beam-heated discharges, an increase in the d-d neutron emission is observed when the pellet ablates. In this case, the increase is due to fusion reactions between beam ions and the high density neutral and plasma cloud produced by ablation of the pellet; this localized density perturbation equilibrates in about 700 ..mu..sec. Analysis of the data indicates that the density propagates without forming a sharp shock front with a rapid initial propagation velocity (greater than or equal to 2 x 10/sup 7/ cm/sec) that subsequently decreases to around 3 x 10/sup 6/ cm/sec. Modelling suggests that the electron heat flux into the pellet cloud is much less than the classical Spitzer value.

  19. Study of the pelletizing process zirconium oxide and zircon sand

    International Nuclear Information System (INIS)

    Seo, E.S.M.; Paschoal, J.O.A.; Acevedo, M.T.P.

    1990-12-01

    The study of the process to obtain zirconium tetrachloride under development at IPEN, can be divide into two steps: pelletizing and chlorination. Pelletizing is an important step in the overall process as it facilitates greater contact between the particles and permits the production of pellets with dimensional uniformity and mechanical strength. In this paper, the results of the study of pelletizing zirconium oxide and zircon sand are presented. The influence of some variables related to the process and the equipment on the physical characteristics of the pellets are discussed. (author)

  20. Investigation on HL-1M pellet shape and cloud structure

    International Nuclear Information System (INIS)

    Zheng Yinjia

    2001-01-01

    When hydrogen multi-pellet flied out from the gun exit and was injected into the HL-1M plasma, the pellet injection and ablation cloud were observed by using a 2D CCD camera SensiCam 360LF. The shape of flight pellet from the gun exit was obtained with the photos taken. The pellet ablation process and the structure of its cloud were analyzed by means of photos with multiple exposure (exp. 100 ns) and long exposure. The experimental setup is described, the results of the pellet injection experiment and characteristic of ablation cloud are presented

  1. High-brightness injector modeling

    International Nuclear Information System (INIS)

    Lewellen, J.W.

    2004-01-01

    There are many aspects to the successful conception, design, fabrication, and operation of high-brightness electron beam sources. Accurate and efficient modeling of the injector are critical to all phases of the process, from evaluating initial ideas to successful diagnosis of problems during routine operation. The basic modeling tasks will vary from design to design, according to the basic nature of the injector (dc, rf, hybrid, etc.), the type of cathode used (thermionic, photo, field emitter, etc.), and 'macro' factors such as average beam current and duty factor, as well as the usual list of desired beam properties. The injector designer must be at least aware of, if not proficient at addressing, the multitude of issues that arise from these considerations; and, as high-brightness injectors continue to move out of the laboratory, the number of such issues will continue to expand.

  2. Review of JT-60 experimental results from June to October, 1988

    International Nuclear Information System (INIS)

    1989-03-01

    After the achievement of AEC (Atomic Energy Commission) milestone in October, 1987, a new divertor coil has been installed to produce divertor plasmas with a single null at the buttom. A pellet injector was also installed during the same shut down period. This report presents the results from the experiment held from June to October in 1988. Major experimental issues during this phase are: 1) confinement and 2) divertor characteristics of lower X-point discharges, 3) enhancement of confinement with pellet injection, 4) ion heating with ICRF of LHRF, 5) current drive with LHRF or ICRF, and evaluation of bootstrap current. (J.P.N.)

  3. Steady state neutral beam injector

    International Nuclear Information System (INIS)

    Mattoo, S.K.; Bandyopadhyay, M.; Baruah, U.K.; Bisai, N.; Chakbraborty, A.K.; Chakrapani, Ch.; Jana, M.R.; Bajpai, M.; Jaykumar, P.K.; Patel, D.; Patel, G.; Patel, P.J.; Prahlad, V.; Rao, N.V.M.; Rotti, C.; Singh, N.P.; Sridhar, B.

    2000-01-01

    Learning from operational reliability of neutral beam injectors in particular and various heating schemes including RF in general on TFTR, JET, JT-60, it has become clear that neutral beam injectors may find a greater role assigned to them for maintaining the plasma in steady state devices under construction. Many technological solutions, integrated in the present day generation of injectors have given rise to capability of producing multimegawatt power at many tens of kV. They have already operated for integrated time >10 5 S without deterioration in the performance. However, a new generation of injectors for steady state devices have to address to some basic issues. They stem from material erosion under particle bombardment, heat transfer > 10 MW/m 2 , frequent regeneration of cryopanels, inertial power supplies, data acquisition and control of large volume of data. Some of these engineering issues have been addressed to in the proposed neutral beam injector for SST-1 at our institute; the remaining shall have to wait for the inputs of the database generated from the actual experience with steady state injectors. (author)

  4. Pellet refueling program at Risoe

    International Nuclear Information System (INIS)

    Andersen, V.; Chang, C.T.; Joergensen, L.W.; Nielsen, P.; Sillesen, A.H.

    1978-01-01

    The pellet refueling work at Riso has up to now been concentrated at studying the ablation rate of hydrogen pellets in hydrogen and deuterium plasmas in the Puffatron device. The main results of these studies are well known and we shall only give a brief summary including some more recent results relating to the ablation process. The work on the Puffatron device has been completed and we are presently preparing to start ablation studies in a small Tokamak, Dante. This tokamak has only been constructed this summer and ablation studies are expected to begin in the beginning of 1978. We shall give the expected parameters of the tokamak plasma and indicate some of the planned work. In this presentation we shall also report on the theoretical work on refueling taking place at Riso. We have particularly been interested in the effect of α-particles which could significantly alter the conclusions made from present experiments

  5. Design of injector section for SPring-8 linac

    International Nuclear Information System (INIS)

    Yoshikawa, Hiroshi; Nakamura, Naoki; Mizuno, Akihiko; Suzuki, Shinsuke; Hori, Toshihiko; Yanagida, Kenichi; Mashiko, Katsuo; Yokomizo, Hideaki

    1993-07-01

    In the SPring-8, we are planning to use positrons in order to increase the beam life time in the storage-ring. For the injector linac, though high current beam production to yield positrons is alternative with accurate low current beam production for commissioning, we designed the injector section to achieve both of the high current mode and the low current mode. In this paper, overview of some simulation codes for the design of electron accelerators are described and the calculation results by TRACE for the injector section of the linac are shown. That is useful not only for the design of machines but for the selection of sensitive parameters to establish the good beam quality. Now the injector section, which is settled at Tokai Establishment, is arranged for the case of the performance check of the electron gun. And we present that the layout of this section is needed to be rearranged for the high current mode operation. (author)

  6. Necessary LIU studies in the injectors during 2012

    International Nuclear Information System (INIS)

    Rumolo, G.; Bartosik, H.; Papaphilippou, Y.

    2012-01-01

    A significant fraction of the Machine Development (MD) time in the LHC injectors in 2011 was devoted to the study of the intensity limitations in the injectors (e.g. space charge effects in PS and SPS, electron cloud effects in the PS and SPS, single bunch and multi-bunch instabilities in PS and SPS, emittance preservation across the injector chain, etc.). The main results achieved in 2011 are presented as well as the questions that still remain unresolved and are of relevance for the LHC Injector Upgrade (LIU) project. 2012 MD will also continue exploring the potential of scenarios that might become operational in the future, like the development of a low gamma transition optics in the SPS or alternative production schemes for the LHC beams in the PS. A tentative prioritized list of studies is provided. (authors)

  7. High Brightness Injectors Based On Photocathode DC Gun

    International Nuclear Information System (INIS)

    B. Yunn

    2001-01-01

    Sample results of new injector design method based on a photocathode dc gun are presented, based on other work analytically proving the validity of the emittance compensation scheme for the case even when beam bunching is involved. We have designed several new injectors appropriate for different bunch charge ranges accordingly. Excellent beam quality produced by these injectors clearly shows that a photocathode dc gun can compete with a rf gun on an equal footing as the source of an electron beam for the bunch charge ranging up to 2 nano Coulomb (nC). This work therefore elevates a dc gun based injector to the preferred choice for many ongoing high brightness accelerator projects considering the proven operational stability and high average power capability of the dc gun

  8. High-rate behaviour of iron ore pellet

    Science.gov (United States)

    Gustafsson, Gustaf; Häggblad, Hans-Åke; Jonsén, Pär; Nishida, Masahiro

    2015-09-01

    Iron ore pellets are sintered, centimetre-sized spheres of ore with high iron content. Together with carbonized coal, iron ore pellets are used in the production of steel. In the transportation from the pelletizing plants to the customers, the iron ore pellets are exposed to different loading situations, resulting in degradation of strength and in some cases fragmentation. For future reliable numerical simulations of the handling and transportation of iron ore pellets, knowledge about their mechanical properties is needed. This paper describes the experimental work to investigate the dynamic mechanical properties of blast furnace iron ore pellets. To study the dynamic fracture of iron ore pellets a number of split Hopkinson pressure bar tests are carried out and analysed.

  9. Progress on Lead Photocathodes for Superconducting Injectors

    CERN Document Server

    Smedley, John; Langner, Jerzy; Lefferts, Richard; Lipski, Andrzej; Rao, Triveni; Sekutowicz, Jacek; Strzyzewski, P

    2005-01-01

    We present the results of our investigation of bulk, electroplated and vacuum deposited lead as suitable photocathode materials for superconducting RF injectors. The quantum efficiency of each sample is presented as a function of the wavelength of the incident light, from 310 nm to 190 nm. Quantum efficiencies of 0.3% have been obtained. Production of a niobium cavity with a lead-plated cathode is underway.

  10. LHC Report: imaginative injectors

    CERN Multimedia

    Pierre Freyermuth for the LHC team

    2016-01-01

    A new bunch injection scheme from the PS to the SPS allowed the LHC to achieve a new peak luminosity record.   Figure 1: PSB multi-turn injection principle: to vary the parameters during injection with the aim of putting the newly injected beam in a different region of the transverse phase-space plan. The LHC relies on the injector complex to deliver beam with well-defined bunch populations and the necessary transverse and longitudinal characteristics – all of which fold directly into luminosity performance. There are several processes taking place in the PS Booster (PSB) and the Proton Synchrotron (PS) acting on the beam structure in order to obtain the LHC beam characteristics. Two processes are mainly responsible for the beam brightness: the PSB multi-turn injection and the PS radio-frequency (RF) gymnastics. The total number of protons in a bunch and the transverse emittances are mostly determined by the multi-turn Booster injection, while the number of bunches and their time spacin...

  11. Quality properties of fuel pellets from forest biomass

    Energy Technology Data Exchange (ETDEWEB)

    Lehtikangas, P.

    1999-07-01

    Nine pellet assortments, made of fresh and stored sawdust, bark and logging residues (a mixture of Norway spruce and Scots pine) were tested directly after production and after 5 months of storage in large bags (volume about 1 m{sup 3} loose pellets) for moisture content, heating value and ash content. Dimensions, bulk density, density of individual pellets and durability were also determined. Moreover, sintering risk and contents of sulphur, chlorine, and lignin of fresh pellets were determined. It is concluded that bark and logging residues are suitable raw materials for pellets production, especially regarding durability and if the ash content is controlled. Pellets density had no effect on its durability, unlike lignin content which was positively correlated. The pellets had higher ash content and lower calorific heating value than the raw materials, probably due to loss of volatiles during drying. In general, the quality changes during storage were not large, but notable. The results showed that storage led to negative effects on durability, especially on pellets made of fresh materials. The average length of pellets was decreased due to breakage during storage. Microbial growth was noticed in some of the pellet assortments. Pellets made out of fresh logging residues were found to be weakest after storage. The tendency to reach the equilibrium with the ambient moisture content should be taken into consideration during production due to the risk of decreasing durability.

  12. An advanced cold moderator using solid methane pellets

    International Nuclear Information System (INIS)

    Foster, C.A.; Carpenter, J.M.

    2001-01-01

    This paper reports developments of the pellet formation and transport technologies required for producing a liquid helium or hydrogen cooled methane pellet moderator. The Phase I US DOE SBIR project, already completed, demonstrated the production of 3 mm transparent pellets of frozen methane and ammonia and transport of the pellets into a 40 cc observation cell cooled with liquid helium. The methane pellets, formed at 72 K, stuck together during the loading of the cell. Ammonia pellets did not stick and fell readily under vibration into a packed bed with a 60% fill fraction. A 60% fill fraction should produce a very significant increase in long-wavelength neutron production and advantages in shorter pulse widths as compared to a liquid hydrogen moderator. The work also demonstrated a method of rapidly changing the pellets in the moderator cell. The Phase II project, just now underway, will develop a full-scale pellet source and transport system with a 1.5 L 'moderator' cell. The Phase II effort will also produce an apparatus to sub-cool the methane pellets to below 20 K, which should prevent the methane pellets from sticking together. In addition to results of the phase I experiments, the presentation includes a short video of the pellets, and a description of plans for the Phase II project. (author)

  13. Experimental setting for assessing mechanical strength of gas hydrate pellet

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, S.J.; Choi, J.H.; Koh, B.H. [Dongguk Univ., Phil-dong, Chung-gu, Seoul (Korea, Republic of). Dept. of Mechanical Engineering

    2008-07-01

    Due to the constant increase in global demand for clean energy, natural gas production from stranded medium and small size gas wells has drawn significant interest. Because the ocean transport of natural gas in the form of solid hydrate pellets (NGHP) has been estimated to be economically feasible, several efforts have been made to develop a total NGHP ocean transport chain. The investigation of mechanical strength of solid-form hydrate pellet has been an important task in fully exploiting the benefit of gas hydrate in the perspective of mass transportation and storage. This paper provided the results of a preliminary study regarding the assessment of mechanical properties of the gas hydrate pellet. The preliminary study suggested some of the key issues regarding formation and strength of gas hydrate pellets. Instead of utilizing the gas hydrate pellet, the study focused on a preliminary test setup for developing the ice pellet which was readily applied to the gas hydrate pellet in the future. The paper described the pelletization of ice powder as well as the experimental setup. Several photographs were illustrated, including samples of ice pellets; compression test for ice pellet using air press and load cell; and the initiation of crack in the cross section of an ice pellet. It was found that mechanical strength, especially, compression strength was not significantly affected by different level of press-forming force up to a certain level. 4 refs., 1 tab., 4 figs.

  14. Description of pelletizing facility

    Energy Technology Data Exchange (ETDEWEB)

    Vojin Cokorilo; Dinko Knezevic; Vladimir Milisavljevic [University of Belgrade, Belgrade (Serbia). Faculty of Mining and Geology

    2006-07-01

    A lot of electrical energy in Serbia was used for heating, mainly for domestics. As it is the most expensive source for heating the government announced a National Program of Energy Efficiency with only one aim, to reduce the consumption of electric energy for the heating. One of the contributions to mentioned reduction is production of coal pellets from the fine coal and its use for domestic heating but also for heating of schools, hospitals, military barracks etc. Annual production of fine coal in Serbia is 300,000 tons. The stacks of fine coal present difficulties at each deep mine because of environmental pollution, spontaneous combustion, low price, smaller market etc. To overcome the difficulties and to give the contribution to National Program of Energy Efficiency researchers from the Department of Mining Engineering, the University of Belgrade designed and realized the project of fine coal pelletizing. This paper describes technical aspect of this project. Using a CPM machine Model 7900, a laboratory facility, then a semi-industrial pelletizing facility followed by an industrial facility was set up and produced good quality pellets. The plant comprised a coal fines hopper, conveyor belt, hopper for screw conveyor, screw conveyor, continuous mixer conditioner, binder reservoir, pump and pipelines, pellet mill, product conveyor belt and product hopper. 4 refs., 3 figs., 1 tab.

  15. Atlas positive-ion injector project

    Energy Technology Data Exchange (ETDEWEB)

    Pardo, R C; Bollinger, L M; Shepard, K W

    1987-04-01

    The goal of the Argonne Positive Ion Injector project is to replace the ATLAS tandem injector with a facility which will increase the beam currents presently available by a factor of 100 and to make beams of essentially all elements including uranium available at ATLAS. The beam quality expected from the facility will be at least as good as that of the tandem based ATLAS. The project combines two relatively new technologies - the electron cyclotron resonance ion source, which provides ions of high charge states at microampere currents, and rf superconductivity which has been shown to be capable of generating accelerating fields as high as 10 MV/m resulting in an essentially new method of acceleration for low-energy heavy ions.

  16. Chromaticity compensation scheme for the Main Injector

    International Nuclear Information System (INIS)

    Bogacz, S.A.

    1993-05-01

    The current Main Injector lattice is studied in the context of full chromaticity compensation in the presence of the eddy current, saturation and the end-pack sextupole fields generated by the dipole magnets. Two families of correcting sextupole magnets are placed to compensate these fields and to adjust the chromaticity (in both planes) to some desired value. Variation of the dipole induced sextupole fields with the B-field (changing along a ramp) are modeled according to recent experimental measurements of the Main Injector dipole magnet Analysis of the required sextupole strengths is carried out along two realistic momentum ramps. The results of our calculation give quantitative insight into the requisite performance of the sextupole magnets

  17. LS1 Report: injectors 2.0

    CERN Multimedia

    Anaïs Schaeffer

    2014-01-01

    Launched in 2009, the Accelerator Controls Renovation Project (ACCOR) will come to an end this year. It was brought in to replace the approximately 450 real-time control systems of the LHC injector complex, some of which were based on technology more than 20 years old.   One of the approximately 450 real-time systems that have been modified in the ACCOR project. These systems, which use special software and thousands of electronics boards, control devices that are essential to the proper functioning of the injectors – the radiofrequency system, the instrumentation, the injection kicker system, the magnets, etc. – and some of them were no longer capable of keeping pace with the LHC. As a result, they urgently needed to be upgraded. "In 2009, after assessing the new technology available on the market, we signed contracts with Europe's most cutting-edge electronics manufacturers," explains Marc Vanden Eynden, ACCOR Project Leader. We then quickly m...

  18. Method of manufacturing UO2 pellet

    International Nuclear Information System (INIS)

    Harada, Yuhei; Asami, Yasuji.

    1989-01-01

    The present invention concerns a method of manufacturing UO 2 pellets with less FP gas release and having fine structure for moderating PCMI. At first, oxide nuclear fuel pellets are placed in a sintering furnance and preliminarily sintered in a H 2 gas atmosphere at 1400 - 1600 degC. In this step, sintering is progressed to about 90 % TD, by which closed cells are formed substantially completely. Then, when sintering is further advanced at an identical temperature in a CO 2 gas atmosphere, growth of the crystal grains is advanced at the central portion of the pellets. Then, reductive heat treatment is applied at the identical temperature in a H 2 gas atmosphere. As a result, pellets having a fine double structure with the larger grain size region being in the central portion and smaller grain size region in the outer periphery can be obtained. (I.J.)

  19. UO2 pellet and manufacturing method

    International Nuclear Information System (INIS)

    Komada, Kiichi; Nishinaka, Keiji; Adachi, Kazunori; Fujiwara, Shuji.

    1995-01-01

    The present invention concerns an uranium dioxide pellet having a large crystal grain size. The grain size of the pellet is enlarged to increase the distance of an FP gas generated in the crystal grain to reach the grain boundary and, as a result, decrease the releasing speed of the FP gas. A UO 2 powder having a specific surface area of from 5 to 50m 2 /g is used as a starting powder in a step of forming a molding product, and chlorine or a chlorine compound is added in such an amount that the chlorine content in the UO 2 pellet is from 3 to 25ppm, in one of a production step, a molding step or a sintering step for UO 2 powder. With such procedures, a UO 2 pellet having a large crystal grain size can be prepared with good reproducibility. (T.M.)

  20. Production of zinc pellets

    Science.gov (United States)

    Cooper, J.F.

    1996-11-26

    Uniform zinc pellets are formed for use in batteries having a stationary or moving slurry zinc particle electrode. The process involves the cathodic deposition of zinc in a finely divided morphology from battery reaction product onto a non-adhering electrode substrate. The mossy zinc is removed from the electrode substrate by the action of gravity, entrainment in a flowing electrolyte, or by mechanical action. The finely divided zinc particles are collected and pressed into pellets by a mechanical device such as an extruder, a roller and chopper, or a punch and die. The pure zinc pellets are returned to the zinc battery in a pumped slurry and have uniform size, density and reactivity. Applications include zinc-air fuel batteries, zinc-ferricyanide storage batteries, and zinc-nickel-oxide secondary batteries. 6 figs.

  1. Uranium dioxide pellets

    International Nuclear Information System (INIS)

    Zawidzki, T.W.

    1982-01-01

    A process for the preparation of a sintered, high density, large crystal grain size uranium dioxide pellet is described which involves: (i) reacting a uranyl nitrate of formula UO 2 (NO 3 ) 2 .6H 2 O with a sulphur source, at a temperature of from about 300 deg. C to provide a sulphur-containing uranium trioxide; (ii) reacting the thus-obtained modified uranium trioxide with ammonium nitrate to form an insoluble sulphur-containing ammonium uranate; (iii) neutralizing the thus-formed slurry with ammonium hydroxide to precipitate out as an insoluble ammonium uranate the remaining dissolved uranium; (iv) recovering the thus-formed precipitates in a dry state; (v) reducing the dry precipitate to UO 2 , and forming it into 'green' pellets; and (vi) sintering the pellets in a hydrogen atmosphere at an elevated temperature

  2. Modeling pellet impact drilling process

    Science.gov (United States)

    Kovalyov, A. V.; Ryabchikov, S. Ya; Isaev, Ye D.; Ulyanova, O. S.

    2016-03-01

    The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rocks. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The experiments conducted has allowed modeling the process of pellet impact drilling, which creates the scientific and methodological basis for engineering design of drilling operations under different geo-technical conditions.

  3. Characteristics of pellet injuries to the orbit.

    Science.gov (United States)

    Kükner, A Sahap; Yilmaz, Turgut; Celebi, Serdal; Karslioğlu, Safak; Alagöz, Gürsoy; Serin, Didem; Acar, M Akif; Ozveren, M Faik

    2009-01-01

    To investigate the features of orbital injuries by pellets fired from the front. Retrospective, 4 cases of pellet injuries. Five orbits of 4 patients who sustained pellet injuries received from the front were reviewed retrospectively. The course of injury and results were assessed. Radiological examinations were reviewed. The patients were evaluated between December 1996 and June 2004. Five orbits of 4 patients sustained injuries caused by pellets fired from an anterior direction. The globe in the injured orbit was intact in 2 cases. Severe loss of vision was also present in these 2 globes due to optic nerve involvement. Final visual acuity was down to no light perception in 4 eyes and limited to light perception in 1 eye. The prognosis of orbital pellet injuries is, unfortunately, poor. A pellet passing through the floor of the orbit often causes double perforation of the globe and, once in the orbital aperture, it travels towards the apex as a result of the conical shape of the orbit and lodges in the optic canal or its entrance, severely damaging the optic nerve. Surgery or other treatments are usually unsuccessful. Even if the globe is intact, vision is usually severely impaired. Copyright 2009 S. Karger AG, Basel.

  4. Summary of energy and particle confinement in pellet-fuelled auxiliary-heated discharges on JET

    International Nuclear Information System (INIS)

    Milora, S.L.; Baylor, L.R.; Bartlett, D.V.

    1989-01-01

    A transient improvement in plasma performance and central confinement has been observed in auxiliary heated JET limiter plasmas associated with a peaking of the plasma density profile and strong centralized heating. Suitable target plasmas for ICRF and NBI heating experiments are created by deuterium pellet injection with a multi pellet injector system developed jointly by ORNL and JETZ . Two types of discharge conditions have been observed. In the first (type A), the density profiles decay gradually during the first 1.3s of the heating pulse while maintaining an elevated density core plasma inside r/a < 0.6 superimposed on a flat density pedestal. During this phase the central electron and ion temperatures increase rapidly (up to 12 keV and 10 keV respectively in the best discharges). This results in an increase in the central plasma pressure by approximately a factor of three (β(0) 5%) above gas fuelled discharges and gives rise to sharply increased pressure gradients in the plasma. An abrupt collapse of the central electron and ion temperatures terminates the enhanced phase at 1.3 s and leads eventually to a 20% decrease in plasma stored energy. While these discharges are predicted to be stable to kink modes, they approach the first stability boundary for ballooning modes in the region of steepest pressure gradient. The pressure and q profiles inferred from transport analysis are also close to those for which intermediate-n mode instability is predicted. (author) 11 refs., 4 figs

  5. On the prediction of spray angle of liquid-liquid pintle injectors

    Science.gov (United States)

    Cheng, Peng; Li, Qinglian; Xu, Shun; Kang, Zhongtao

    2017-09-01

    The pintle injector is famous for its capability of deep throttling and low cost. However, the pintle injector has been seldom investigated. To get a good prediction of the spray angle of liquid-liquid pintle injectors, theoretical analysis, numerical simulations and experiments were conducted. Under the hypothesis of incompressible and inviscid flow, a spray angle formula was deduced from the continuity and momentum equations based on a control volume analysis. The formula was then validated by numerical and experimental data. The results indicates that both geometric and injection parameters affect the total momentum ratio (TMR) and then influence the spray angle formed by liquid-liquid pintle injectors. TMR is the pivotal non-dimensional number that dominates the spray angle. Compared with gas-gas pintle injectors, spray angle formed by liquid-liquid injectors is larger, which benefits from the local high pressure zone near the pintle wall caused by the impingement of radial and axial sheets.

  6. Study on biodiesel heat transfer through self-temperature limit injector during vehicle cold start

    Directory of Open Access Journals (Sweden)

    Wang Jun

    2015-01-01

    Full Text Available A type of Self-Temperature Limit-Injector (STL- injector is proposed to reduce the biodiesel consumption and emission in vehicle cold start process. The STL-injector is capable of fast raising fuel temperature, which helps improve the quality of diesel spray and its combustion efficiency. A STL-injector model is established with consideration of electro-mechanic coupling and fluid-structure interaction. A transient simulation is conducted using dynamic grid technology. The results show that STL-injector can effectively raise biodiesel temperature to 350K from 300K in 32 seconds. That is to say, adding STL-injector to existing biodiesel combustion system is an environment-friendly solution due to improving atomization and spray quality quickly.

  7. Investigation of pellet acceleration by an arc heated gas gun

    International Nuclear Information System (INIS)

    Andersen, P.; Andersen, S.A.; Bundgaard, J.; Baekmark, L.; Hansen, B.H.; Jensen, V.O.; Kossek, H.; Michelsen, P.K.; Nordskov, A.; Sass, B.; Soerensen, H.; Weisberg, K.V.

    1987-06-01

    This report describes work on pellet acceleration by means of an arc heated gas gun. The work is a continuation of the work described in RISO-M-2536. The aim of the work is to obtain velocities well above 2 km/s for 3.2 mm diameter deuterium pellets. By means of a cryogenic arc chamber in which the hydrogen propellant is pre-condensed, extruded deutetrium pellets are accelerated up to a maximum velocity of 1.93 km/s. When increasing the energy input to the arc in order to increase the pellet velocity further the heat input to the extrusion/punching pellet loading mechanism was found to be critical: preparation of pellets became difficult and cooling times between shots became inconveniently long. In order to circumvent this problems the concept of a room temperature hydrogen propellant pellet fed arc chamber was proposed. Preliminary results from acceleration of polyurethane pellets with this arc chamber are described as well as the work of developing of feed pellet guns for this chamber. Finally the report describes design consideration for a high pressure propellant pellet fed arc chamber together with preliminary results obtained with a proto-type arc chamber. (author)

  8. Influences on particle shape in underwater pelletizing processes

    Energy Technology Data Exchange (ETDEWEB)

    Kast, O., E-mail: oliver.kast@ikt.uni-stuttgart.de, E-mail: matthias.musialek@ikt.uni-stuttgart.de, E-mail: kalman.geiger@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de; Musialek, M., E-mail: oliver.kast@ikt.uni-stuttgart.de, E-mail: matthias.musialek@ikt.uni-stuttgart.de, E-mail: kalman.geiger@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de; Geiger, K., E-mail: oliver.kast@ikt.uni-stuttgart.de, E-mail: matthias.musialek@ikt.uni-stuttgart.de, E-mail: kalman.geiger@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de; Bonten, C., E-mail: oliver.kast@ikt.uni-stuttgart.de, E-mail: matthias.musialek@ikt.uni-stuttgart.de, E-mail: kalman.geiger@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de [Institut für Kunststofftechnik, University of Stuttgart (Germany)

    2014-05-15

    Underwater pelletizing has gained high importance within the last years among the different pelletizing technologies, due to its advantages in terms of throughput, automation, pellet quality and applicability to a large variety of thermoplastics. The resulting shape and quality of pellets, however, differ widely, depending on material characteristics and effects not fully understood yet. In an experimental set-up, pellets of different volumes and shapes were produced and the medium pellet mass, the pellet surface and the bulk density were analyzed in order to identify the influence of material properties and process parameters. Additionally, the shaping kinetics at the die opening were watched with a specially developed camera system. It was found that rheological material properties correlate with process parameters and resulting particle form in a complex way. Higher cutting speeds were shown to have a deforming influence on the pellets, leading to less spherical s and lower bulk densities. More viscous materials, however, showed a better resistance against this. Generally, the viscous properties of polypropylene proofed to be dominant over the elastic ones in regard to their influence on pellet shape. It was also shown that the shapes filmed at the die opening and the actual form of the pellets after a cooling track do not always correlate, indicating a significant influence of thermodynamic properties during the cooling.

  9. Experimental Investigation of Characteristics of a Double-Base Swirl Injector in a Liquid Rocket Propellant Engine

    Directory of Open Access Journals (Sweden)

    Fathollah OMMI

    2009-07-01

    Full Text Available In this work the fundamentals of swirl injector calculation is investigated and new design procedure is proposed. The design method for double-base liquid-liquid injectors is presented based on this theory and experimental results. Then special conditions related to double-based liquid-liquid injectors are studied and the corresponding results are applied in design manipulation. The behaviour of injector in various performing conditions is studied, and the design procedure is presented based on obtained results. A computer code for designing the injector is proposed. Based on this code, four injectors are manufactured. A specialized laboratory was setup for the measurement of macroscopic spray characteristics under different pressure such as homogeneous droplet distribution, spray angle, swirl effect. Finally, through PDA cold test, the microscopic characteristics of injectors spray are also obtained and measured. The results, which will be explained in detail, are satisfactory.

  10. Nuclear fuel pellets

    International Nuclear Information System (INIS)

    Larson, R.I.; Brassfield, H.C.

    1981-01-01

    Increased strength and physical durability in green bodies or pellets formed of particulate nuclear fuel oxides is achieved by inclusion of a fugitive binder which is ammonium bicarbonate, bicarbonate carbomate, carbomate, sesquicarbonate or mixtures thereof. Ammonium oxadate may be included as pore former. (author)

  11. Fuel rod pellet loading head

    International Nuclear Information System (INIS)

    Howell, T.E.

    1975-01-01

    An assembly for loading nuclear fuel pellets into a fuel rod comprising a loading head for feeding pellets into the open end of the rod is described. The pellets rest in a perforated substantially V-shaped seat through which air may be drawn for removal of chips and dust. The rod is held in place in an adjustable notched locator which permits alignment with the pellets

  12. DIAGNOSTICS AND REGENERATION OF COMMON RAIL INJECTORS

    Directory of Open Access Journals (Sweden)

    Łukasz KONIECZNY

    2015-03-01

    Full Text Available The article presents the methodology of Common Rail injector diagnostic, regeneration and regulation with use of professional test stands. The EPS 815 machine can be used to test and repair all BOSCH injectors fully satisfying the producer requirements and standards. The article describes an example injector diagnosis with use of such test stand and additionally presents appropriate injector regeneration and encoding techniques

  13. Degradation of copepod fecal pellets

    DEFF Research Database (Denmark)

    Poulsen, Louise K.; Iversen, Morten

    2008-01-01

    amount of fecal pellets. The total degradation rate of pellets by the natural plankton community of Oresund followed the phytoplankton biomass, with maximum degradation rate during the spring bloom (2.5 +/- 0.49 d(-1)) and minimum (0.52 +/- 0.14 d(-1)) during late winter. Total pellet removal rate ranged...

  14. Impact of palm biodiesel blend on injector deposit formation

    International Nuclear Information System (INIS)

    Liaquat, A.M.; Masjuki, H.H.; Kalam, M.A.; Fazal, M.A.; Khan, Abdul Faheem; Fayaz, H.; Varman, M.

    2013-01-01

    Highlights: • 250 h Endurance test on 2 fuel samples; diesel fuel and PB20. • Visual inspection of injectors running on DF and PB20 showed deposit accumulation. • SEM and EDS analysis showed less injector deposits for DF compared to PB20 blend. • Engine oil analysis showed higher value of wear particles for PB20 compared to DF. - Abstract: During short term engine operation, renewable fuels derived from vegetable oils, are capable of providing good engine performance. In more extended operations, some of the same fuels can cause degradation of engine performance, excessive carbon and lacquer deposits and actual damage to the engine. Moreover, temperatures in the area of the injector tip due to advanced diesel injection systems may lead to particularly stubborn deposits at and around the injector tip. In this research, an endurance test was carried out for 250 h on 2 fuel samples; DF (diesel fuel) as baseline and PB20 (20% palm biodiesel and 80% DF) in a single cylinder CI engine. The effects of DF and PB20 on injector nozzle deposits, engine lubricating oil, and fuel economy and exhaust emissions were investigated. According to the results of the investigation, visual inspection showed some deposit accumulation on injectors during running on both fuels. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis showed greater carbon deposits on and around the injector tip for PB20 compared to the engine running with DF. Similarly, lubricating oil analysis presented excessive wear metal concentrations, decreased viscosity and increased density values when the engine was fuelled with PB20. Finally, fuel economy and emission results during the endurance test showed higher brake specific fuel consumption (bsfc) and NO x emissions, and lower HC and CO emissions, for the PB20 blend compared to DF

  15. Pellets standard on the way

    International Nuclear Information System (INIS)

    Laeng, H.-P.

    2001-01-01

    This short article introduces the Swiss standard that has been adapted from the German standard for heating pellets made of untreated wood. The various requirements placed on the materials used in the manufacture of the pellets and their influence on the pollution emissions produced by boilers and ovens using the pellets as a heating fuel are listed. Further points in the standard referring to declarations to be made by the manufacturer, size and specific weight of the pellets and instructions for the storage and burning of the pellets are discussed

  16. Nuclear fuel pellet loading apparatus

    International Nuclear Information System (INIS)

    Gerkey, K.S.

    1979-01-01

    An automatic apparatus for loading a predetermined amount of nuclear fuel pellets into a nuclear fuel element to be used in a nuclear reactor is described. The apparatus consists of a vibratory bed capable of supporting corrugated trays containing rows of nuclear fuel pellets and arranged in alignment with the open ends of several nuclear fuel elements. A sweep mechanism is arranged above the trays and serves to sweep the rows of fuel pellets onto the vibratory bed and into the fuel element. A length detecting system, in conjunction with a pellet stopping mechanism, is also provided to assure that a predetermined amount of nuclear fuel pellets are loaded into each fuel element

  17. New features of the MAX IV thermionic pre-injector

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, J., E-mail: joel.andersson@maxiv.lu.se; Olsson, D., E-mail: david.olsson@maxiv.lu.se; Curbis, F.; Malmgren, L.; Werin, S.

    2017-05-21

    The MAX IV facility in Lund, Sweden consists of two storage rings for production of synchrotron radiation. The smaller 1.5 GeV ring is presently under construction, while the larger 3 GeV ring is being commissioned. Both rings will be operating with top-up injections from a full-energy injector. During injection, the electron beam is first delivered to the main injector from a thermionic pre-injector which consists of a thermionic RF gun, a chopper system, and an energy filter. In order to reduce losses of high-energy electrons along the injector and in the rings, the electron beam provided by the thermionic pre-injector should have the correct time structure and energy distribution. In this paper, the design of the MAX IV thermionic pre-injector with all its sub components is presented. The electron beam delivered by the pre-injector and its dependence on parameters such as optics, cathode temperature, and RF power are studied. Measurements are here compared with simulation results obtained by particle tracking and electromagnetic codes. The chopper system is described in detail, and different driving schemes that optimize the injection efficiency for the two storage rings are investigated. During operation, it was discovered that the structure of the beam delivered by the gun is affected by mode beating between the accelerating and a low-order mode. This mode beating is also studied in detail. Finally, initial measurements of the electron beam delivered to the 3 GeV ring during commissioning are presented.

  18. INTOR neutral beam injector concept

    International Nuclear Information System (INIS)

    Metzler, D.H.; Stewart, L.D.

    1981-01-01

    The US INTOR phase 1 effort in the plasma heating area is described. Positive ion based sources extrapolated from present day technology are proposed. These sources operate at 175 keV beam energy for 6 s. Five injectors - plus one spare - inject 75 MW. Beam energy, source size, interface, radiation hardening, and many other studies are summarized

  19. New developments of HIF injector

    Directory of Open Access Journals (Sweden)

    Liang Lu

    2018-01-01

    Full Text Available The ultra-high intensity heavy-ion beam is highly pursued for heavy-ion researches and applications. However, it is limited by heavy-ion production of ion source and space-charge-effect in the low energy region. The Heavy-ion Inertial Fusion (HIF facilities were proposed in 1970s. The HIF injectors have large cavity number and long total length, e.g., there are 27 injectors in HIDIF and HIBLIC is 30 km in length, and the corresponding HIF facilities are too large and too expensive to be constructed. Recently, ion acceleration technologies have been developing rapidly, especially in the low energy region, where the acceleration of high intensity heavy-ions is realized. Meanwhile, superconducting (SC acceleration matures and increases the acceleration gradient in medium and high energy regions. The length of HIF injectors can be shortened to a buildable length of 2.5 km. This paper will present a review of a renewed HIF injector, which adopts multi-beam linac-based cavities. Keywords: Heavy-ion inertial fusion (HIF, Radio frequency quadrupole (RFQ, IH cavity, Heavy-ion, Multi-beam accelerator, PACS Codes: 52.58.Hm, 28.52.Av, 29.20.Ej, 29.27.-a, 29.27.Ac, 41.75.Lx

  20. Nuclear fuel pellet loading machine

    International Nuclear Information System (INIS)

    Dazen, J.R.; Denero, J.V.

    1976-01-01

    A nuclear fuel pellet loading machine is described including an inclined rack mounted on a base and having parallel spaced grooves on its upper surface arranged to support fuel rods. A fuel pellet tray is adapted to be placed on a table spaced from the rack, the tray having columns of fuel pellets which are in alignment with the open ends of fuel rods located in the rack grooves. A transition plate is mounted between the fuel rod rack and the fuel pellet tray to receive and guide the pellets into the open ends of the fuel rods. The pellets are pushed into the fuel rods by a number of mechanical fingers mounted on a motor operated block which is moved along the pellet tray length by a drive screw driven by the motor. To facilitate movement of the pellets in the fuel rods the rack is mounted on a number of spaced vibrators which vibrate the fuel rods during fuel pellet insertion. A pellet sensing device movable into an end of each fuel rod indicates to an operator when each rod has been charged with the correct number of pellets

  1. Preliminary pellet injection experiment in the Gamma 10 tandem mirror

    Energy Technology Data Exchange (ETDEWEB)

    Kawamori, Eiichirou; Tamano, Teruo; Nakashima, Yousuke; Yoshikawa, Masayuki; Kobayashi, Shinji; Cho, Teruji; Ishii, Kameo; Yatsu, Kiyoshi [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki (Japan); Mase, Atsushi [Advanced Sceince and Technology Center for Cooperative Research, Kyushu University, Kasuga, Fukuoka (Japan)

    2000-07-01

    In the GAMMA 10 tandem mirror, pellet injection experiments have been started as a solution for the density limit problem. This is the first pellet injection experiment in open systems. We describe the possibilities of confinement of pellet fueled particles. For that, we measure the number of end loss particles and compare them with pellet fueled ones in various conditions of confining potentials. The deterioration of confining potential with the pellet injection is a fundamental issue. The results show that the ion confining potential recover faster than central electron temperature due to thermal barrier. We also consider the operating space for fueling method. It is demonstrated that the operating space for pellet injection exceeds gas fueled one on hot ion mode plasmas. (author)

  2. Description of pelletizing facility

    Directory of Open Access Journals (Sweden)

    Čokorilo Vojin

    2006-01-01

    Full Text Available A lot of electrical energy in Serbia was used for heating, mainly for domes- tics. As it is the most expensive source for heating the government announced a National Program of Energy Efficiency with only one aim, to reduce the consumption of electric energy for the heating. One of the contributions to mentioned reduction is production of coal pellets from the fine coal and its use for domestic heating but also for heating of schools, hospitals, military barracks, etc. Annual production of fine coal in Serbia is 300,000 tons. The stacks of fine coal make a lot difficulties to the each mine because of environmental pollution, spontaneous combustion, low price, smaller market, etc. To prevent the difficulties and to give the contribution to National Program of Energy Efficiency researchers from the Department of Mining Engineering, University of Belgrade, designed and realized the project of fine coal pelletizing. This paper describes technical aspect of this project.

  3. Nuclear fuel pellet collating system and method

    International Nuclear Information System (INIS)

    Rieben, S.L.; Kugler, R.W.; Scherpenberg, J.J.; Wiersema, D.T.

    1990-01-01

    This patent describes a method of collating nuclear fuel pellets. It comprises: supporting a plurality of pellet supply trays and a plurality of pellet storage trays at a tray positioning station. Each of the supply trays containing in at least one row thereon a plurality of nuclear fuel pellets of an enrichment different from the enrichment pellets on at least some other of the supply trays; transferring one pellet supply tray from the tray positioning station and disposing the same at an input station of a pellet collating line; transferring one pellet storage tray from the tray positioning station and disposing the same at an output station of the pellet collating line; sweeping pellets in the at least one row thereof from the one pellet supply tray onto a work station of the pellet collating line located between the input and output stations thereof; measuring a desired length of pellets in the at least one row on the work station and separating the measured desired length of pellets from the remaining pellets, if any, in the row thereof; sweeping the remaining pellets, if any, in the row from the work station back onto the one pellet supply tray; transferring the one pellet supply tray and remaining pellets, if any, back to the tray positioning station; sweeping the measured desired length of pellets from the work station onto the one pellet storage tray; and transferring the one pellet storage tray and measured desired length of pellets back to the tray positioning station

  4. Characteristics of an electron-beam rocket pellet accelerator

    International Nuclear Information System (INIS)

    Tsai, C.C.; Foster, C.A.; Schechter, D.E.

    1989-01-01

    An electron-beam rocket pellet accelerator has been designed, built, assembled, and tested as a proof-of-principle (POP) apparatus. The main goal of accelerators based on this concept is to use intense electron-beam heating and ablation of a hydrogen propellant stick to accelerate deuterium and/or tritium pellets to ultrahigh speeds (10 to 20 km/s) for plasma fueling of next-generation fusion devices such as the International Thermonuclear Engineering Reactor (ITER). The POP apparatus is described and initial results of pellet acceleration experiments are presented. Conceptual ultrahigh-speed pellet accelerators are discussed. 14 refs., 8 figs

  5. Fuel compliance model for pellet-cladding mechanical interaction

    International Nuclear Information System (INIS)

    Shah, V.N.; Carlson, E.R.

    1985-01-01

    This paper describes two aspects of fuel pellet deformation that play significant roles in determining maximum cladding hoop strains during pellet-cladding mechanical interaction: compliance of fragmented fuel pellets and influence of the pellet end-face design on the transmission of axial compressive force in the fuel stack. The latter aspect affects cladding ridge formation and explains several related observations that cannot be explained by the hourglassing model. An empirical model, called the fuel compliance model and representing the above aspects of fuel deformation, has been developed using the results from two Halden experiments and incorporated into the FRAP-T6 fuel performance code

  6. Effect of pelleting process variables on physical properties and sugar yields of ammonia fiber expansion pretreated corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Amber N. Hoover; Jaya Shankar Tumuluru; Farzaneh Teymouri; Garold L. Gresham; Janette Moore

    2014-07-01

    Pelletization process variables including grind size (4, 6 mm), die speed (40, 50, 60 Hz), and preheating (none, 70 degrees C) were evaluated to understand their effect on pellet quality attributes and sugar yields of ammonia fiber expansion (AFEX) pretreated biomass. The bulk density of the pelletized AFEX corn stover was three to six times greater compared to untreated and AFEX-treated corn stover. Also the durability of the pelletized AFEX corn stover was >97.5% for all pelletization conditions studied except for preheated pellets. Die speed had no effect on enzymatic hydrolysis sugar yields of pellets. Pellets produced with preheating or a larger grind size (6 mm) had similar or lower sugar yields. Pellets generated with 4 mm AFEX-treated corn stover, a 60 Hz die speed, and no preheating resulted in pellets with similar or greater density, durability, and sugar yields compared to other pelletization conditions.

  7. The wood pellet market in Austria: A structural market model analysis

    International Nuclear Information System (INIS)

    Kristöfel, Christa; Strasser, Christoph; Schmid, Erwin; Morawetz, Ulrich B.

    2016-01-01

    EU bioenergy policies and oil price hikes have resulted in a significant increase of installed pellet boilers for residential heating. Hence, European demand for wood pellets has been growing faster and more steadily than supply leading to rising market prices in recent years. This article presents an econometric analysis of demand and supply of wood pellets in the residential heating sector in Austria, one of the most dynamic markets for residential pellets. Annual and monthly time series data between 2000 and 2014 are used in a two-stage least-squares (2SLS) regression to estimate supply and demand elasticities of wood pellets. In all model specifications, pellets demand is found to be inelastic (from −0.66 to −0.76) and pellets supply unit-elastic (from 1.03 to 1.18). Thus, consumers are highly exposed to price changes resulting from supply shocks. Policies which support investments in pellet boilers will shift the demand of wood pellets and likely leading to higher prices for consumers. - Highlights: • Characterisation of the European pellet market. • A structural market model for wood pellets in Austria. • Estimation of supply and demand price elasticities using a two-stage least-squares (2SLS) regression. • Pellets demand is found to be inelastic and pellets supply unit-elastic in the short run. • Policies stimulating demand will likely increase pellet and sawmill by-product prices.

  8. Opportunities for Pellet Trade - Towards a Single European Pellet Market

    International Nuclear Information System (INIS)

    Pigaht, Maurice; Janssen, Rainer; Rutz, Dominik; Boehm, Thorsten; Vasen, Norbert; Vegas, Laura; Karapanagiotis, Nicolas

    2006-01-01

    The potential for Pellets trade in Europe was researched and assessed. Such trade is of key importance for the development of a European pellet market of sufficient supply, demand, price and quality standards. Three target markets were taken as case studies for the trade assessment: Greece, Spain and Italy. All three markets stand to profit greatly from international trade. For these markets, pellet imports could supply the basis for the development of a domestic boiler market. At the same time, pellet exports would allow the planning of larger pellet production plants. Whilst these additional costs amount to some 10-20% of the Pellets price, they are financially acceptable, especially for new markets and 'peaks' in the demand/supply of established markets

  9. Experimental and numerical investigation of a porous fuel injector

    Energy Technology Data Exchange (ETDEWEB)

    Reijnders, J.

    2009-03-15

    Diesel engines are the most fuel efficient engines for transportation. However the details of the mixing and combustion process in the cylinders result in relatively high emissions of soot. In his graduation work the author developed a new type of fuel injection system for Diesel engines. The injection from the developed porous injector nozzle can be regarded as the limiting case of injection from very many, very small holes. Furthermore it is expected that the improved combustion characteristics yielded much less soot emissions. After the computational determination of an optimal geometry for the porous nozzle, experiments have been performed. The results of the prototypes showed a rather homogeneous hemispherical spray shape. The author conducted tests that showed that the mass flow, at constant pressure, of the porous injector is higher than the conventional one. This means that the pressure can be set lower or injection time can be shortened. A patent is applied and obtained for this innovative injector.

  10. ILSE-ESQ injector scaled experiment

    International Nuclear Information System (INIS)

    Henestroza, E.; Eylon, S.; Yu, S.; Grote, D.

    1993-01-01

    A 2 MeV, 800 mA, K + injector for the Heavy Ion Fusion Induction Linac Systems Experiments (ISLE) is under development at LBL. It consists of a 500keV-1MeV diode pre-injector followed by an electrostatic quadrupole accelerator (ESQ). One of the key issues for the ESQ centers around the control of beam aberrations due to the open-quotes energy effectclose quotes: in a strong electrostatic quadrupole field, ions at beam edge will have energies very different from those on the axis. The resulting kinematic distortions lead to S-shaped phase spaces, which, if uncorrected, will lead eventually to emittance growth. These beam aberrations can be minimized by increasing the injection energy and/or strengthening the beam focusing. It may also be possible to compensate for the open-quotes energy effectclose quotes by proper shaping of the quadrupoles electrodes. In order to check the physics of the open-quotes energy effectclose quotes of the ESQ design a scaled experiment has been designed that will accommodate the parameters of the source, as well as the voltage limitations, of the Single Beam Transport Experiment (SBTE). Since the 500 KeV pre-injector delivers a 4 cm converging beam, a quarter-scale experiment will fit the 1 cm converging beam of the SBTE source. Also, a 10 mA beam in SBTE, and the requirement of equal perveance in both systems, forces all the voltages to scale down by a factor 0.054. Results from this experiment and corresponding 3D PIC simulations will be presented

  11. Optimization of a multi-parameter model for biomass pelletization to investigate temperature dependence and to facilitate fast testing of pelletization behavior

    DEFF Research Database (Denmark)

    Holm, Jens Kai; Stelte, Wolfgang; Posselt, Dorthe

    2011-01-01

    Pelletization of biomass residues increases the energy density, reduces storage and transportation costs and results in a homogeneous product with well-defined physical properties. However, raw materials for fuel pellet production consist of ligno-cellulosic biomass from various resources...... and error” experiments and personal experience. However in recent years the utilization of single pellet press units for testing the biomass pelletizing properties has attracted more attention. The present study outlines an approach where single pellet press testing is combined with modeling to mimic...... the pelletizing behavior of new types of biomass in a large scale pellet mill. This enables a fast estimation of key process parameters such as optimal press channel length and moisture content. Secondly, the study addresses the question of the origin of the observed relationship between pelletizing pressure...

  12. Drug release, preclinical and clinical pharmacokinetics relationships of alginate pellets prepared by melt technology.

    Science.gov (United States)

    Bose, Anirbandeep; Harjoh, Nurulaini; Pal, Tapan Kumar; Dan, Shubhasis; Wong, Tin Wui

    2016-01-01

    Alginate pellets prepared by the aqueous agglomeration technique experience fast drug dissolution due to the porous pre-formed calcium alginate microstructure. This study investigated in vitro drug release, preclinical and clinical pharmacokinetics relationships of intestinal-specific calcium acetate-alginate pellets against calcium-free and calcium carbonate-alginate pellets. Alginate pellets were prepared by solvent-free melt pelletization instead of aqueous agglomeration technique using chlorpheniramine maleate as model drug. A fast in situ calcium acetate dissolution in pellets resulted in rapid pellet breakup, soluble Ca(2+) crosslinking of alginate fragments and drug dissolution retardation at pH 1.2, which were not found in other pellet types. The preclinical drug absorption rate was lower with calcium acetate loaded than calcium-free alginate pellets. In human subjects, however, the extent and the rate of drug absorption were higher from calcium acetate-loaded pellets than calcium-free alginate pellets. The fine, dispersible and weakly gastric mucoadhesive calcium alginate pellets underwent fast human gastrointestinal transit. They released the drug at a greater rate than calcium-free pellets in the intestine, thereby promoting drug bioavailability. Calcium acetate was required as a disintegrant more than as a crosslinking agent clinically to promote pellet fragmentation, fast gastrointestinal transit and drug release in intestinal medium, and intestinal-specific drug bioavailability.

  13. PELLETS AND PELLETIZATION: EMERGING TRENDS IN THE PHARMA INDUSTRY.

    Science.gov (United States)

    Zaman, Muhammad; Saeed-Ul-Hassan, Syed; Sarfraz, Rai Muhammad; Batool, Nighat; Qureshi, Muhammad Junaid; Akram, Muhammad Abdullah; Munir, Saiqa; Danish, Zeeshan

    2016-11-01

    The present time is considered as an era of advancements in drug delivery systems. Different novel approaches are under investigation that range from uniparticulate to multi particulate system, macro to micro and nano particulate systems. Pelletization is one of the novel drug delivery technique that provides an effective way to deliver the drug in modified pattern. It is advantageous in providing site specific delivery of the drug. Drugs with unpleasant taste, poor bioavailability and short biological half-life can be delivered efficiently through pellets. Their reduced size makes them more valuable as compared to the conventional drug deliv- ery system. Different techniques are used to fabricate the pellets such as extrusion and spheronization, hot melt extrusion, powder layering, suspension or solution layering, freeze pelletization and pelletization by direct compression method. Various natural polymers including xanthan gum, guar gum, tragacanth and gum acacia, semisynthetic polymers like cellulose derivatives, synthetic polymers like derivatives of acrylamides, can be used in pellets formulation. Information provided in this review is collected from various national and intemational research articles, review articles and literature available in the books. The purpose of the current review is to discuss pellets, their characterizations, different techniques of pelletization and the polymers with potential of being suitable for pellets formulation.

  14. Fuel pellets from biomass - Processing, bonding, raw materials

    Energy Technology Data Exchange (ETDEWEB)

    Stelte, W.

    2011-12-15

    The present study investigates several important aspects of biomass pelletization. Seven individual studies have been conducted and linked together, in order to push forward the research frontier of biomass pelletization processes. The first study was to investigate influence of the different processing parameters on the pressure built up in the press channel of a pellet mill. It showed that the major factor was the press channel length as well as temperature, moisture content, particle size and extractive content. Furthermore, extractive migration to the pellet surface at an elevated temperature played an important role. The second study presented a method of how key processing parameters can be estimated, based on a pellet model and a small number of fast and simple laboratory trials using a single pellet press. The third study investigated the bonding mechanisms within a biomass pellet, which indicate that different mechanisms are involved depending on biomass type and pelletizing conditions. Interpenetration of polymer chains and close intermolecular distance resulting in better secondary bonding were assumed to be the key factors for high mechanical properties of the formed pellets. The outcome of this study resulted in study four and five investigating the role of lignin glass transition for biomass pelletization. It was demonstrated that the softening temperature of lignin was dependent on species and moisture content. In typical processing conditions and at 8% (wt) moisture content, transitions were identified to be at approximately 53-63 deg. C for wheat straw and about 91 deg. C for spruce lignin. Furthermore, the effects of wheat straw extractives on the pelletizing properties and pellet stability were investigated. The sixth and seventh study applied the developed methodology to test the pelletizing properties of thermally pre-treated (torrefied) biomass from spruce and wheat straw. The results indicated that high torrefaction temperatures above 275 deg

  15. Development of technologies on innovative-simplified nuclear power plant using high-efficiency steam injectors (5) operating characteristics of center water jet type supersonic steam injector

    International Nuclear Information System (INIS)

    Abe, Y.; Kawamoto, Y.; Iwaki, C.; Narabayashi, T.; Mori, M.; Ohmori, S.

    2005-01-01

    Next-generation reactor systems have been under development aiming at simplified system and improvement of safety and credibility. A steam injector has a function of a passive pump without large motor or turbo-machinery, and has been investigated as one of the most important component of the next-generation reactor. Its performance as a pump depends on direct contact condensation phenomena between a supersonic steam and a sub-cooled water jet. As previous studies of the steam injector, there are studies about formulation of operating characteristic of steam injector and analysis of jet structure in steam injector by Narabayashi etc. And as previous studies of the direct contact condensation, there is the study about the direct contact condensation in steam atmosphere. However the study about the turbulent heat transfer under the great shear stress is not enough investigated. Therefore it is necessary to examine in detail about the operating characteristic of the steam injector. The present paper reports the observation results of the water jet behavior in the super sonic steam injector by using the video camera and the high-speed video camera. And the measuring results of the temperature and the pressure distribution in the steam injector are reported. From observation results by video camera, it is cleared that the water jet is established at the center of the steam injector right after steam supplied and the operation of the steam injector depends on the throat diameter. And from observation results by high-speed video camera, it is supposed that the columned water jet surface is established in the mixing nozzle and the water jet surface movement exists. And from temperature measuring results, it is supposed that the steam temperature at the mixing nozzle is changed between about 80 degree centigrade and about 60 degree centigrade. Then from the pressure measuring results, it is confirmed that the pressure at the diffuser depends on each the throat diameter and

  16. Nuclear fuel pellet loading machine

    International Nuclear Information System (INIS)

    Kee, R.W.; Denero, J.V.

    1975-01-01

    An apparatus for loading nuclear fuel pellets on trays for transfer in a system is described. A conveyor supplies pellets from a source to a loading station. When the pellets reach a predetermined position at the loading station, a manual or automatically operated arm pushes the pellets into slots on a tray and this process is repeated until pellet sensing switches detect that the tray is full. Thereupon, the tray is lowered onto a belt or other type conveyor and transferred to other apparatus in the system, such as a furnace for sintering, and in some cases, reduction of UO 2 . 2 to UO 2 . The pellets are retained on the tray and subsequently loaded directly into fuel rods to be used in the reactor core. (auth)

  17. First operation of the ATLAS positive-ion injector

    International Nuclear Information System (INIS)

    Pardo, R.C.; Bollinger, L.M.; Shephard, K.W.; Billquist, P.J.; Bogaty, J.M.; Clifft, B.E.; Harkewicz, R.; Munson, F.H.; Nolen, J.A.; Zinkann, G.P.

    1992-01-01

    The construction of the ATLAS Positive-Ion Injector (PII) is complete and beam acceleration tests are underway. The PII consists of an ECR ion source, on a high-voltage platform, providing beam to a low-velocity-acceptance, independently-phased, superconducting linac. This injector enables the ATLAS facility to accelerate any heavy ion, including uranium, to energies in excess of the Coulomb barrier. The design accelerating field performance has been exceeded, with an average accelerating field of approximately 3.2 MV/m achieved in early tests. Initial beam tests of the entire injector indicate that all important performance goals have been met. This paper describes the results of these early tests and discusses our initial operating experience with the whole ATLAS system. (Author) 5 refs., tab., fig

  18. Heavy-Ion Injector for the High Current Experiment

    Science.gov (United States)

    Bieniosek, F. M.; Henestroza, E.; Kwan, J. W.; Prost, L.; Seidl, P.

    2001-10-01

    We report on progress in development of the Heavy-Ion Injector at LBNL, which is being prepared for use as an injector for the High Current Experiment (HCX). It is composed of a 10-cm-diameter surface ionization source, an extraction diode, and an electrostatic quadrupole (ESQ) accelerator, with a typical operating current of 0.6 A of potassium ions at 1.8 MeV, and a beam pulse length of 4.5 microsecs. We have improved the Injector equipment and diagnostics, and have characterized the source emission and radial beam profiles at the diode and ESQ regions. We find improved agreement with EGUN predictions, and improved compatibility with the downstream matching section. Plans are to attach the matching section and the initial ESQ transport section of HCX. Results will be presented and compared with EGUN and WARP simulations.

  19. First operation of the ATLAS Positive-Ion Injector

    International Nuclear Information System (INIS)

    Pardo, R.C.; Bollinger, L.M.; Shepard, K.W.; Billquist, P.J.; Bogaty, J.M.; Clifft, B.E.; Harkewicz, R.; Munson, F.H.; Nolen, J.A.; Zinkann, G.P.

    1992-01-01

    The construction of the ATLAS Positive-Ion Injector (PII) is complete and beam acceleration tests are underway. The PII consists of an ECR ion source, on a high-voltage platform, providing beam to a low-velocity-acceptance, independently-phased, superconducting linac. This injector enables the ATLAS facility to accelerate any heavy ion, including uranium, to energies in excess of the Coulomb barrier. The design accelerating field performance has been exceeded, with an average accelerating field of approximately 3.2 MV/m achieved in early tests. Initial beam tests of the entire injector indicate tat all important performance goals have been met. This paper describes the results of these early tests and discusses our initial operating experience with the whole ATLAS system

  20. Necessary LIU studies in the injectors during 2012

    CERN Document Server

    Rumolo, G; Papaphilippou, Y

    2012-01-01

    A significant fraction of the Machine Development (MD) time in the LHC injectors in 2011 was devoted to the study of the intensity limitations in the injectors (e.g. space charge effects in PS and SPS, electron cloud effects in the PS and SPS, single bunch and multi-bunch instabilities in PS and SPS, emittance preservation across the injector chain, etc.). The main results achieved in 2011 will be presented as well as the questions that still remain unresolved and are of relevance for the LIU project. 2012 MDs will also continue exploring the potential of scenarios that might become operational in the future, like the development of a low gamma transition optics in the SPS or alternative production schemes for the LHC beams in the PS. A tentative prioritized list of studies is provided.

  1. Injector linac of SPring-8

    International Nuclear Information System (INIS)

    Yoshikawa, H.; Hori, T.; Suzuki, S.; Yanagida, K.; Itoh, Y.; Mizuno, A.; Taniuchi, T.; Sakaki, H.; Kuba, A.; Fukushima, S.; Kobayashi, T.; Asaka, T.; Yokomizo, H.

    1996-01-01

    The linac that is SPring-8 injector was completed and started operation from August 1. A beam was able to be transported to the final beam dumping at a tail end on August 8. From now on this linac carries out beam adjustment and be scheduled to do a beam injection to a synchrotron in October. The construction and fundamental performance of the linac are described. (author)

  2. Pellets direct from the forest

    International Nuclear Information System (INIS)

    Keel, A.

    2006-01-01

    This article takes a look at developments in the market for wood pellets and their production from forest wood. The general situation in the booming pellets market is reviewed and the potential of this climate-neutral form of heating is discussed. Figures and prognoses on the use of wood pellets are presented. In particular, the potential for the use of forestry wood supplies to augment the use of wood wastes and sawdust from sawmills is looked at

  3. Micromorphology of pelletized soil conditioners

    Science.gov (United States)

    Hirsch, Florian; Dietrich, Nils; Knoop, Christine; Raab, Thomas

    2017-04-01

    Soil conditioners produced by anaerobic digestion and subsequent composting of organic household waste, bear the potential to improve unproductive farmland together with a reduced input risk of unwanted pollutants into the soils. Within the VeNGA project (http://www.biogas-network.de/venga), soil conditioners from anaerobically digested organic household waste are tested for their potential to increase plant growth in glasshouse and field experiments. Because the production techniques of these soil conditioners may influence their physical and chemical behaviour in the soil, two different techniques for pelletizing the soil conditioners where applied. We present findings from a pot experiment with cereal that has been sampled after two months for micromorphological analyses. We visualize the decomposition and the physical behaviour of the soil conditioners. Pellets produced in an agglomeration mixer result in dense balls, that are only slightly decomposed after the trial. But the soil conditioners created under pressure in a screw extruder are rich in voids and have the potential of retaining more soil water.

  4. Pellet ablation and ablation model development

    International Nuclear Information System (INIS)

    Houlberg, W.A.

    1989-01-01

    A broad survey of pellet ablation is given, based primarily on information presented at this meeting. The implications of various experimental observations for ablation theory are derived from qualitative arguments of the physics involved. The major elements of a more complete ablation theory are then outlined in terms of these observations. This is followed by a few suggestions on improving the connections between theory and experimental results through examination of ablation data. Although this is a rather aggressive undertaking for such a brief (and undoubtedly incomplete) assessment, some of the discussion may help us advance the understanding of pellet ablation. 17 refs

  5. Status of the positive ion injector for ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Den Hartog, P K; Benaroya, R; Bogaty, J M; Bollinger, L M; Clifft, B E; Craig, S L; Henderson, D; Markovich, P; Munson, F; Nixon, J M; Pardo, R C; Phillips, D; Shepard, K W; Tilbrook, I; Zinkann, G [Argonne National Lab., IL (USA). Physics Div.

    1989-04-01

    The positive ion injector project will replace a High Voltage Engineering Corp. model FN 9 MV tandem electrostatic accelerator as the injector into the ATLAS superconducting heavy ion linear accelerator. It consists of an electron cyclotron resonance (ECR) ion source on a 350-kV platform injecting into a linac of individually phased superconducting resonators which have been optimized for ions with velocities as low as {beta} = 0.009. The resulting combination will extend the useful mass range of ATLAS to projectiles as heavy as uranium, while increasing the beam currents available by a factor of 100. (orig.).

  6. A Compact Multi-Beamlets High Current Injector for HIFDrivers

    Energy Technology Data Exchange (ETDEWEB)

    Kwan, J.W.; Bieniosek, F.M.; Grote, D.P.; Westenskow, G.A.

    2005-09-06

    Using curved electrodes in the injector, an array of converging beamlets can produce a beam with the envelope radius, convergence, and ellipticity matched to an electrostatic quadrupole (ESQ) channel. Experimental results were in good quantitative agreement with simulation and have demonstrated the feasibility of this concept. The size of a driver-scale injector system using this approach will be several times smaller than the one designed using traditional single large-aperture beams, so the success of this experiment has significant economical and technical impacts on the architecture of heavy ion fusion (HIF) drivers.

  7. Injector modeling and achievement/maintenance of high brightness

    International Nuclear Information System (INIS)

    Boyd, J.K.

    1985-10-01

    Viewgraphs for the workshop presentation are given. The presentation has three fundamental parts. In part one the need for numerical calculations is justified and the available computer codes are enumerated. The capabilities and features of the DPC computer code are the focal point in this section. In part two the injector design issues are discussed. These issues include such things as the beam optics and magnetic field profile. In part three the experimental results of two injector designs are compared with DPC predictions. 8 figs

  8. Status of the positive ion injector for ATLAS

    International Nuclear Information System (INIS)

    Den Hartog, P.K.; Benaroya, R.; Bogaty, J.M.

    1988-01-01

    The positive ion injector project will replace a High Voltage Engineering Corp. model FN 9 MV tandem electrostatic accelerator as the injector into the ATLAS superconducting heavy ion linear accelerator. It consists of an electron cyclotron resonance (ECR) ion source on a 350-kV platform injecting into a linac of individually phased superconducting resonators which have been optimized for ions with velocities as low as β = 0.009. The resulting combination will extend the useful mass range of ATLAS to projectiles as heavy as uranium, while increasing the beam currents available by a factor of 100. (2 refs., 2 figs., 1 tab.)

  9. Sintering of dioxide pellets in an oxidizing atmosphere (CO2)

    International Nuclear Information System (INIS)

    Santos, G.R.T.

    1992-01-01

    This work consists in the study of the sintering process of U O 2 pellets in an oxidizing atmosphere. Sintering tests were performed in an CO 2 atmosphere and the influence of temperature and time on the pellets density and microstructure were verified. The results obtained were compared to those from the conventional sintering process and its efficiency was confirmed. (author)

  10. Pellet injection experiments on tokamaks in ASIPP, China

    International Nuclear Information System (INIS)

    Yang, Y.; Bao, Y.; Li, J.; Gu, X.; He, Y.

    2001-01-01

    Pellet injection has been proved to be an effective method for deep fueling of fusion devices. Improvements of both the particle confinement and the energy confinement were observed in many experiments. In HT-6M and HT-7 tokamaks, single and multi-pellet experiments are tried, and attractive results are obtained. (author)

  11. Pellet injection experiments on tokamaks in ASIPP, China

    International Nuclear Information System (INIS)

    Yang, Y.; Bao, Y.; Li, J.; Gu, X.; He, Y.

    1999-01-01

    Pellet Injection has been proven to be an effective method for deep fuelling of fusion devices. Improvements of both the particle confinement and the energy confinement were observed in many experiments. In HT-6M and HT-7 tokamaks, single and multi-pellet experiments are tried, and attractive results are obtained

  12. Water jet behavior in center water jet type supersonic steam injector

    International Nuclear Information System (INIS)

    Kawamoto, Y.; Abe, Y.

    2005-01-01

    Next-generation reactor systems have been under development aiming at simplified system and improvement of safety and credibility. A steam injector has a function of a passive pump without large motor or turbo-machinery, and has been investigated as one of the most important component of the next-generation reactor. Its performance as a pump depends on direct contact condensation phenomena between a supersonic steam and a sub-cooled water jet. As previous studies of the steam injector, there are studies about formulation of operating characteristic of steam injector and analysis of jet structure in steam injector by Narabayashi etc. And as previous studies of the direct contact condensation, there is the study about the direct contact condensation in steam atmosphere. However the study about the turbulent heat transfer under the great shear stress is not enough investigated. Therefore it is necessary to examine in detail about the operating characteristic of the steam injector. The present paper reports the observation results of the water jet behavior in the super sonic steam injector by using the video camera and the high-speed video camera. And the measuring results of the temperature and the pressure distribution in the steam injector are reported. From observation results by video camera, it is cleared that the water jet is established at the center of the steam injector right after steam supplied and the operation of the steam injector depends on the throat diameter. And from observation results by high-speed video camera, it is supposed that the columned water jet surface is established in the mixing nozzle and the water jet surface movement exists. Furthermore and effect of the non-condensable gas on the steam injector is investigated by measuring the radial temperature distributions in the water jet. From measuring results, it is supposed the more the air included in the steam, the more the temperature fluctuation of both steam and discharge water

  13. Hydrogen pellet injection device

    International Nuclear Information System (INIS)

    Kanno, Masahiro.

    1992-01-01

    In a hydrogen pellet injection device, a nozzle block having a hydrogen gas supply channel is disposed at the inner side of a main cryogenic housing, and an electric resistor is attached to the block. Further, a nozzle block and a hydrogen gas introduction pipe are attached by way of a thermal insulating spacer. Electric current is supplied to the resistor to positively heat the nozzle block and melt remaining solid hydrogen in the hydrogen gas supply channel. Further, the effect of temperature elevation due to the resistor is prevented from reaching the side of the hydrogen gas introduction pipe by the thermal insulation spacer. That is, the temperature of the nozzle block is directly and positively elevated, to melt the solid hydrogen rapidly. Preparation operation from the injection of the hydrogen pellet to the next injection can be completed in a shorter period of time compared with a conventional case thereby enabling to make the test more efficient. Further, only the temperature of the nozzle block is elevated with no effect of temperature elevation due to the resistor to other components by the thermal insulation flange. (N.H.)

  14. Considerations on the DEMO pellet fuelling system

    Energy Technology Data Exchange (ETDEWEB)

    Lang, P.T., E-mail: peter.lang@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany); Day, Ch. [Karlsruhe Institute of Technology, 76021 Karlsruhe (Germany); Fable, E. [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany); Igitkhanov, Y. [Karlsruhe Institute of Technology, 76021 Karlsruhe (Germany); Köchl, F. [Association EURATOM-Ö AW/ATI, Atominstitut, TU Wien, 1020 Vienna (Austria); Mooney, R. [Culham Centre for Fusion Energy, Culham Science Centre, Oxfordshire OX14 3DB (United Kingdom); Pegourie, B. [CEA, IRFM, 13108 Saint-Paul-lez-Durance (France); Ploeckl, B. [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany); Wenninger, R. [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany); EFDA, Garching (Germany); Zohm, H. [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany)

    2015-10-15

    Graphical abstract: - Highlights: • Considerations are made for a core particle fuelling system covering all DEMO requirements. • Particle deposition beyond the pedestal top is needed to achieve efficient fuelling. • Conventional pellet technology enabling launching from the torus inboard side can be used. • Efforts have been taken for integrating a suitable pellet guiding system into the EU DEMO model. • In addition, further techniques bearing potential for advanced fuelling performance are considered. - Abstract: The Demonstration Fusion Power Reactor DEMO is the step foreseen to bridge the gap between ITER and the first commercial fusion power plant. One key element in the European work plan for DEMO is the elaboration of a conceptual design for a suitable core particle fuelling system. First considerations for such a system are presented in this contribution. Following the well-considered ITER solution, most analysis performed in this study assumes conventional pellet technology will be used for the fuelling system. However, taking advantage of the less compressed time frame for the DEMO project, several other techniques thought to bear potential for advanced fuelling performance are considered as well. In a first, basic analysis all actuation parameters at hand and their implications on the fuelling performance were considered. Tentative transport modeling of a reference scenario strongly indicates only particles deposited inside the plasma pedestal allow for efficient fuelling. Shallow edge fuelling results in an unbearable burden on the fuel cycle. Sufficiently deep particle deposition seems technically achievable, provided pellets are launched from the torus inboard at sufficient speed. All components required for a DEMO pellet system capable for high speed inboard pellet launch are already available or can be developed in due time with reasonable efforts. Furthermore, steps to integrate this solution into the EU DEMO model are taken.

  15. Considerations on the DEMO pellet fuelling system

    International Nuclear Information System (INIS)

    Lang, P.T.; Day, Ch.; Fable, E.; Igitkhanov, Y.; Köchl, F.; Mooney, R.; Pegourie, B.; Ploeckl, B.; Wenninger, R.; Zohm, H.

    2015-01-01

    Graphical abstract: - Highlights: • Considerations are made for a core particle fuelling system covering all DEMO requirements. • Particle deposition beyond the pedestal top is needed to achieve efficient fuelling. • Conventional pellet technology enabling launching from the torus inboard side can be used. • Efforts have been taken for integrating a suitable pellet guiding system into the EU DEMO model. • In addition, further techniques bearing potential for advanced fuelling performance are considered. - Abstract: The Demonstration Fusion Power Reactor DEMO is the step foreseen to bridge the gap between ITER and the first commercial fusion power plant. One key element in the European work plan for DEMO is the elaboration of a conceptual design for a suitable core particle fuelling system. First considerations for such a system are presented in this contribution. Following the well-considered ITER solution, most analysis performed in this study assumes conventional pellet technology will be used for the fuelling system. However, taking advantage of the less compressed time frame for the DEMO project, several other techniques thought to bear potential for advanced fuelling performance are considered as well. In a first, basic analysis all actuation parameters at hand and their implications on the fuelling performance were considered. Tentative transport modeling of a reference scenario strongly indicates only particles deposited inside the plasma pedestal allow for efficient fuelling. Shallow edge fuelling results in an unbearable burden on the fuel cycle. Sufficiently deep particle deposition seems technically achievable, provided pellets are launched from the torus inboard at sufficient speed. All components required for a DEMO pellet system capable for high speed inboard pellet launch are already available or can be developed in due time with reasonable efforts. Furthermore, steps to integrate this solution into the EU DEMO model are taken.

  16. Design status of heavy ion injector program

    International Nuclear Information System (INIS)

    Ballard, E.O.; Meyer, E.A.; Rutkowski, H.L.; Shurter, R.P.; Van Haaften, F.W.; Riepe, K.B.

    1985-01-01

    Design and development of a sixteen beam, heavy ion injector is in progress at Los Alamos National Laboratory (LANL) to demonstrate the injector technology for the High Temperature Experiment (HTE) proposed by Lawrence Livermore Laboratory (LBL). The injector design provides for individual ion sources mounted to a support plate defining the sixteen beam array. The beamlets are electrostatically accelerated through a series of electrodes inside an evacuated (10 -7 torr) high voltage (HV) accelerating column

  17. Direct Fuel Injector Power Drive System Optimization

    Science.gov (United States)

    2014-04-01

    solenoid coil to create magnetic field in the stator. Then, the stator pulls the pintle to open the injector nozzle . This pintle movement occurs when the...that typically deal with power strategies to the injector solenoid coil. Numerical simulation codes for diesel injection systems were developed by...Laboratory) for providing the JP-8 test fuel. REFERENCES 1. Digesu, P. and Laforgia D., “ Diesel electro- injector : A numerical simulation code”. Journal of

  18. Numerical Simulation of Twin Nozzle Injectors

    OpenAIRE

    Milak, Dino

    2015-01-01

    Fuel injectors for marine applications have traditionally utilized nozzles with symmetric equispaced orifice configuration. But in light of the new marine emission legislations the twin nozzle concept has arisen. The twin nozzle differs from the conventional configuration by utilizing two closely spaced orifices to substitute each orifice in the conventional nozzle. Injector manufacturers regard twin nozzle injectors as a promising approach to facilitate stable spray patterns independent of t...

  19. ELM mitigation with pellet ELM triggering and implications for PFCs and plasma performance in ITER

    Energy Technology Data Exchange (ETDEWEB)

    Baylor, Larry R. [ORNL; Lang, P. [EURATOM / UKAEA, Abingdon, UK; Allen, S. L. [Lawrence Livermore National Laboratory (LLNL); Lasnier, C. J. [Lawrence Livermore National Laboratory (LLNL); Meitner, Steven J. [ORNL; Combs, Stephen Kirk [ORNL; Commaux, Nicolas JC [ORNL; Loarte, A. [ITER Organization, Cadarache, France; Jernigan, Thomas C. [ORNL

    2015-08-01

    The triggering of rapid small edge localized modes (ELMs) by high frequency pellet injection has been proposed as a method to prevent large naturally occurring ELMs that can erode the ITER plasma facing components (PFCs). Deuterium pellet injection has been used to successfully demonstrate the on-demand triggering of edge localized modes (ELMs) at much higher rates and with much smaller intensity than natural ELMs. The proposed hypothesis for the triggering mechanism of ELMs by pellets is the local pressure perturbation resulting from reheating of the pellet cloud that can exceed the local high-n ballooning mode threshold where the pellet is injected. Nonlinear MHD simulations of the pellet ELM triggering show destabilization of high-n ballooning modes by such a local pressure perturbation.A review of the recent pellet ELM triggering results from ASDEX Upgrade (AUG), DIII-D, and JET reveals that a number of uncertainties about this ELM mitigation technique still remain. These include the heat flux impact pattern on the divertor and wall from pellet triggered and natural ELMs, the necessary pellet size and injection location to reliably trigger ELMs, and the level of fueling to be expected from ELM triggering pellets and synergy with larger fueling pellets. The implications of these issues for pellet ELM mitigation in ITER and its impact on the PFCs are presented along with the design features of the pellet injection system for ITER.

  20. A numerical study of candidate transverse fuel injector configurations in the Langley scramjet engine

    Science.gov (United States)

    Drummond, J. P.

    1980-01-01

    A computer program has been developed that numerically solves the two-dimensional Navier-Stokes and species equations near one or more transverse hydrogen fuel injectors in a scramjet engine. The program currently computes the turbulent mixing and reaction of hydrogen fuel and air, and allows the study of separated regions of the flow immediately preceding and following the injectors. The complex shock-expansion structure produced by the injectors in this region of the engine can also be represented. Results are presented that describe the flow field near two opposing transverse fuel injectors and two opposing staged (multiple) injectors, and comparisons between the two configurations are made to assess their mixing and flameholding qualities.

  1. Additive Manufacturing of Fuel Injectors

    Energy Technology Data Exchange (ETDEWEB)

    Sadek Tadros, Dr. Alber Alphonse [Edison Welding Institute, Inc., Columbus, OH (United States); Ritter, Dr. George W. [Edison Welding Institute, Inc., Columbus, OH (United States); Drews, Charles Donald [Edison Welding Institute, Inc., Columbus, OH (United States); Ryan, Daniel [Solar Turbines Inc., San Diego, CA (United States)

    2017-10-24

    Additive manufacturing (AM), also known as 3D-printing, has been shifting from a novelty prototyping paradigm to a legitimate manufacturing tool capable of creating components for highly complex engineered products. An emerging AM technology for producing metal parts is the laser powder bed fusion (L-PBF) process; however, industry manufacturing specifications and component design practices for L-PBF have not yet been established. Solar Turbines Incorporated (Solar), an industrial gas turbine manufacturer, has been evaluating AM technology for development and production applications with the desire to enable accelerated product development cycle times, overall turbine efficiency improvements, and supply chain flexibility relative to conventional manufacturing processes (casting, brazing, welding). Accordingly, Solar teamed with EWI on a joint two-and-a-half-year project with the goal of developing a production L-PBF AM process capable of consistently producing high-nickel alloy material suitable for high temperature gas turbine engine fuel injector components. The project plan tasks were designed to understand the interaction of the process variables and their combined impact on the resultant AM material quality. The composition of the high-nickel alloy powders selected for this program met the conventional cast Hastelloy X compositional limits and were commercially available in different particle size distributions (PSD) from two suppliers. Solar produced all the test articles and both EWI and Solar shared responsibility for analyzing them. The effects of powder metal input stock, laser parameters, heat treatments, and post-finishing methods were evaluated. This process knowledge was then used to generate tensile, fatigue, and creep material properties data curves suitable for component design activities. The key process controls for ensuring consistent material properties were documented in AM powder and process specifications. The basic components of the project

  2. The Manufacturing Process of Bamboo Pellets

    Science.gov (United States)

    Zhijia Liu; Zehui Jiang; Zhiyong Cai; Benhua Fei; Xing' e Liu

    2012-01-01

    Bamboo was a kind of biomass materials and had great potential as a bio-energy resource of the future in China. The physical and combustion properties of bamboo pellets were determined and the effects of moisture content (MC) and sizes of particle on these properties were investigated in this research. The results showed that MC and sizes of particle affected these...

  3. Patient satisfaction with ExtaviPro™ 30G, a new auto-injector for administering interferon β-1b in multiple sclerosis: results from a real-world, observational EXCHANGE study.

    Science.gov (United States)

    Hoffmann, Frank A; Trenova, Anastasiya; Llaneza, Miguel A; Fischer, Johannes; Lus, Giacomo; von Bredow, Dorothea; Lara, Núria; Lam, Elaine; Van Hoef, Marlies; Bakshi, Rajesh

    2017-08-09

    Patients with multiple sclerosis (MS) receiving long-term, subcutaneous interferon β-1b (IFN β-1b; Extavia®) often experience injection-site reactions and injection-site pain, which together with other side-effects (such as flu-like symptoms) result in suboptimal treatment compliance/adherence. The EXCHANGE study evaluated patient satisfaction with IFN β-1b treatment, administered using ExtaviPro™ 30G, a new auto-injector, in a real-world setting. This 26-week, open-label, prospective, non-interventional, observational, multi-country multi-centre study enrolled patients with MS who had been treated with IFN β-1b or other disease-modifying therapies with a self-administered auto-injector for ≥3 months and who were planned to switch to IFN β-1b treatment administered using ExtaviPro™ 30G as part of routine clinical care. Patient-reported outcomes included overall patient satisfaction (primary outcome) and satisfaction associated with treatment effectiveness, convenience and side-effects, assessed using Treatment Satisfaction Questionnaire for Medication (TSQM)-14. The changes in TSQM scores from baseline to Week 26 were reported. All data were analysed using SAS statistical software (version 9.4). Of the 336 patients enrolled, 324 were included in the analysis. At baseline, mean ± standard deviation (SD) age of patients was 41.8 ± 11.3 years and 68.2% were women. The mean ± SD of MS disease duration was 6.9 ± 6.6 years, and the majority of patients (94.1%) had relapsing-remitting MS. The mean ± SD of TSQM score for overall patient satisfaction at Week 26 was 75.6 ± 16.46 (baseline, 73.0 ± 17.14; p = 0.0342). The mean ± SD of TSQM subscale scores for patient satisfaction with effectiveness, side-effects and convenience were 75.0 ± 18.65 (baseline, 71.6 ± 19.45; p = 0.0356), 88.5 ± 18.98 (baseline, 82.7 ± 22.93; p = 0.0002) and 77.6 ± 16.72 (baseline, 71.1 ± 17.53; p patient satisfaction, including

  4. Pelletizing and combustion of wood from thinning; Pelletering och foerbraenning av gallringsvirke

    Energy Technology Data Exchange (ETDEWEB)

    Oerberg, Haakan; Thyrel, Mikael; Kalen, Gunnar; Larsson, Sylvia

    2007-12-14

    huge problems by sintering in boilers and burners. Good quality stem wood pellets show an ash melting temperature >1500 deg C. The assortment Pine limbed which has shown the lowest ash melting temperature 1270-1320 deg C can be critical for combustion and needs very god temperature control to avoid sintering. For the rest of the different assortments, ash melting temperatures have been over 1500 deg C which indicates good ash melting characteristics. Emissions in flue gases were measured during test combustion. All measured parameters showed that this wood material from thinnings could be burned very efficiently and with low emissions. The largest difference was registered between emissions of NO{sub x} from the different assortments. The assortment Mixed limbed gave the highest NO{sub x} value 70 mg/MJ fuel, and the assortment Pine delimbed gave the lowest NO{sub x} value 46 mg/MJ fuel. Other emissions of CO, HC and SO{sub x} that were measured showed very low values. Pelletizing characteristics of the different assortments were defined by four different parameters: 1.Production capacity (kg/h), 2. Energy consumption (kWh/ton), 3. Density of produced pellets (kg/m{sup 3}) and 4. Durability of produced pellets. The measurements show that all assortments have pelletizing characteristics comparable with pure stem wood. Best results were obtained with Mixed limbed, which gave high production capacity and therefore low energy consumption, and durable pellets with acceptable density. The assortment Birch delimbed was most difficult to pelletize which resulted in high energy consumption and high-density pellets. After storing one year all assortments were pelletized again. Results from those tests show that pelletizing characteristics of the material had changed during storage. Assortment Mixed undelimbed and Birch delimbed could not be pelletized successfully. These materials could not be transported evenly enough in to the pelletizer. Material flow characteristics had

  5. Preparation and characterization of a self-emulsifying pellet formulation.

    Science.gov (United States)

    Abdalla, Ahmed; Mäder, Karsten

    2007-05-01

    The purpose of the current study is to investigate the feasibility of producing solid self-emulsifying pellets using the extrusion/spheronization technique. Pellets were made from a mixture of C18 partial glycerides, Solutol HS15 and microcrystalline cellulose. Pellets with good physical properties (size, shape, friability) and self-emulsifying properties were produced. The pellets were, in contrast to pellets lacking Solutol, able to transfer a lipophilic dye and a spin probe into the aqueous media. The release kinetics and the microenvironment of the pellets during the release process were assessed using electron spin resonance (ESR) spectroscopy. The ESR results showed that the hydrophobic spin probe was localized mainly in the lipid environment all over the release time. Furthermore, the formulation was capable of accelerating the release of the drug diazepam and achieving a diazepam concentration above its saturation solubility. In conclusion, spherical pellets with low friability and self-emulsifying properties can be produced by the standard extrusion/spheronization technique. The pellets are capable of transfering lipophilic compounds into the aqueous phase and have a high potential to increase the bioavailability of lipophilic drugs.

  6. Experimental study of curved guide tubes for pellet injection

    International Nuclear Information System (INIS)

    Combs, S.K.; Baylor, L.R.; Foust, C.R.; Gouge, M.J.; Jernigan, T.C.; Milora, S.L.

    1997-01-01

    The use of curved guide tubes for transporting frozen hydrogen pellets offers great flexibility for pellet injection into plasma devices. While this technique has been previously employed, an increased interest in its applicability has been generated with the recent ASDEX Upgrade experimental data for magnetic high-field side (HFS) pellet injection. In these innovative experiments, the pellet penetration appeared to be significantly deeper than for the standard magnetic low-field side injection scheme, along with corresponding greater fueling efficiencies. Thus, some of the major experimental fusion devices are planning experiments with HFS pellet injection. Because of the complex geometries of experimental fusion devices, installations with multiple curved guide tube sections will be required for HFS pellet injection. To more thoroughly understand and document the capability of curved guide tubes, an experimental study is under way at the Oak Ridge National Laboratory (ORNL). In particular, configurations and pellet parameters applicable for the DIII-D tokamak and the International Thermonuclear Experimental Reactor (ITER) were simulated in laboratory experiments. Initial test results with nominal 2.7- and 10-mm-diam deuterium pellets are presented and discussed

  7. Nuclear fuel pellet transfer escalator

    International Nuclear Information System (INIS)

    Huggins, T.B. Sr.; Roberts, E.; Edmunds, M.O.

    1991-01-01

    This patent describes a nuclear fuel pellet escalator for loading nuclear fuel pellets into a sintering boat. It comprises a generally horizontally-disposed pellet transfer conveyor for moving pellets in single file fashion from a receiving end to a discharge end thereof, the conveyor being mounted about an axis at its receiving end for pivotal movement to generally vertically move its discharge end toward and away from a sintering boat when placed below the discharge end of the conveyor, the conveyor including an elongated arm swingable vertically about the axis and having an elongated channel recessed below an upper side of the arm and extending between the receiving and discharge ends of the conveyor; a pellet dispensing chute mounted to the arm of the conveyor at the discharge end thereof and extending therebelow such that the chute is carried at the discharge end of the conveyor for generally vertical movement therewith toward and away from the sintering boat

  8. Analysis of pellet coating uniformity using a computer scanner.

    Science.gov (United States)

    Šibanc, Rok; Luštrik, Matevž; Dreu, Rok

    2017-11-30

    A fast method for pellet coating uniformity analysis, using a commercial computer scanner was developed. The analysis of the individual particle coating thicknesses was based on using a transparent orange colored coating layer deposited on white pellet cores. Besides the analysis of the coating thickness the information of pellet size and shape was obtained as well. Particle size dependent coating thickness and particle size independent coating variability was calculated by combining the information of coating thickness and pellet size. Decoupling coating thickness variation sources is unique to presented method. For each coating experiment around 10000 pellets were analyzed, giving results with a high statistical confidence. Proposed method was employed for the performance evaluation of classical Wurster and swirl enhanced Wurster coater operated at different gap settings and air flow rates. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Influence of Reduced Mass Flow Rate and Chamber Backpressure on Swirl Injector Fluid Mechanics

    Science.gov (United States)

    Kenny, R Jeremy; Hulka, James R.

    2008-01-01

    Industry interest in variable-thrust liquid rocket engines places a demand on engine injector technology to operate over a wide range of liquid mass flow rates and chamber backpressures. One injection technology of current interest for variable thrust applications is an injector design with swirled fluids. Current swirl injector design methodologies do not take into account how swirl injector design parameters respond to elevated chamber backpressures at less than design mass flow rates. The current work was created to improve state-of-the-art swirl injector design methods in this area. The specific objective was to study the effects of elevated chamber backpressure and off-design mass flow rates on swirl injector fluid mechanics. Using a backpressure chamber with optical access, water was flowed through a swirl injector at various combinations of chamber backpressure and mass flow rates. The film thickness profile down the swirl injector nozzle section was measured through a transparent nozzle section of the injector. High speed video showed measurable increases in the film thickness profile with application of chamber backpressure and mass flow rates less than design. At prescribed combinations of chamber backpressure and injected mass flow rate, a discrete change in the film thickness profile was observed. Measured injector discharge coefficient values showed different trends with increasing chamber backpressure at low mass flow rates as opposed to near-design mass flow rates. Downstream spray angles showed classic changes in morphology as the mass flow rate was decreased below the design value. Increasing chamber backpressure decreased the spray angle at any injection mass flow rate. Experimental measurements and discussion of these results are reported in this paper.

  10. Design/cost of an induction linac for heavy ions for pellet-fusion

    International Nuclear Information System (INIS)

    Faltens, A.; Hoyer, E.; Keefe, D.; Laslett, L.J.

    1979-03-01

    The physics of the pellet implosion sets stringent conditions on the accelerator driver. The beam energy should be > 1 MJ, the beam power > 100 TW (implying a pulse length approx. = 10 ns), and the specific energy deposition in the pellet > 20 MJ/g. Thus, considerable current amplification is required, e.g. from some 10 amps at the source to perhaps 10 kiloamps at the pellet. Most of this amplification can be accomplished continuously along the accelerator and the remainder achieved at the end by bunching in the final transport lines to the target chamber. A conceptual schematic of an Induction Linac Fusion Driver is shown, which includes an injector, an accelerator-buncher, and a final transport system. Here only the accelerator portion of the driver is discussed

  11. Pellet fueling of JET plasmas during ohmic, ICRF and NBI heating

    International Nuclear Information System (INIS)

    Gondhalekar, A.; Cheetham, A.; Bures, M.

    1986-01-01

    Pellet fueling experiments have been performed on JET using a single-shot pneumatic injector giving 4.6mm (4.5 x 10 21 D atoms) and 3.6mm (2.2 x 10 21 D atoms) diameter cylindrical deuterium pellets with velocity 0.8 ≤ V(km.s -1 ) ≤ 1.2. Z/sub eff/ 20 m -3 and T/sub e/(0) ≅ 1keV. Separately, high value of n/sub D/(0)tau/sub E/T/sub i/(0) = 1.3 x 10 20 m -3 .s.keV at T/sub i/90) = 6.5keV has been obtained with pellet fueling followed by NBI heating

  12. Solid deuterium pellet injection with a two-stage pneumatic gun

    International Nuclear Information System (INIS)

    Reggiori, A.; Riva, G.; Daminelli, G.; Frattolillo, A.; Martinis, L.; Scaramuzzi, F.

    1989-01-01

    Recent results on injection of D 2 pellets, using an improved light gas gun, are reported. In order to overcome the limits imposed by the low mechanical strength of solid hydrogen, a double-piston gun has been developed, in which the pressure pulse can be shaped in different ways, allowing reduction of the maximum acceleration of the pellet. Experiments have been performed with plastic and D 2 pellets. Velocities above 2500 m/s have been obtained with unbroken D 2 pellets

  13. Ion source and injector development

    International Nuclear Information System (INIS)

    Curtis, C.D.

    1976-01-01

    This is a survey of low energy accelerators which inject into proton linacs. Laboratories covered include Argonne, Brookhaven, CERN, Chalk River, Fermi, ITEP, KEK, Rutherford, and Saclay. This paper emphasizes complete injector systems, comparing significant hardware features and beam performance data, including recent additions. There is increased activity now in the acceleration of polarized protons, H + and H - , and of unpolarized H - . New source development and programs for these ion beams is outlined at the end of the report. Heavy-ion sources are not included

  14. Circular economy in drinking water treatment: reuse of ground pellets as seeding material in the pellet softening process.

    Science.gov (United States)

    Schetters, M J A; van der Hoek, J P; Kramer, O J I; Kors, L J; Palmen, L J; Hofs, B; Koppers, H

    2015-01-01

    Calcium carbonate pellets are produced as a by-product in the pellet softening process. In the Netherlands, these pellets are applied as a raw material in several industrial and agricultural processes. The sand grain inside the pellet hinders the application in some high-potential market segments such as paper and glass. Substitution of the sand grain with a calcite grain (100% calcium carbonate) is in principle possible, and could significantly improve the pellet quality. In this study, the grinding and sieving of pellets, and the subsequent reuse as seeding material in pellet softening were tested with two pilot reactors in parallel. In one reactor, garnet sand was used as seeding material, in the other ground calcite. Garnet sand and ground calcite performed equally well. An economic comparison and a life-cycle assessment were made as well. The results show that the reuse of ground calcite as seeding material in pellet softening is technologically possible, reduces the operational costs by €38,000 (1%) and reduces the environmental impact by 5%. Therefore, at the drinking water facility, Weesperkarspel of Waternet, the transition from garnet sand to ground calcite will be made at full scale, based on this pilot plant research.

  15. Numerical investigations of the WASA pellet target operation and proposal of a new technique for the PANDA pellet target

    Energy Technology Data Exchange (ETDEWEB)

    Varentsov, Victor L., E-mail: v.varentsov@gsi.de [Institute for Theoretical and Experimental Physics, B. Cheremushkinskaya 25, 117218 Moscow (Russian Federation)

    2011-08-01

    The conventional nozzle vibration technique of the hydrogen micro-droplet generation that is supposed to be used for internal pellet target production for the future PANDA experiment at the international FAIR facility in Darmstadtfor is described. The operation of this technique has been investigated by means of detailed computer simulations. Results of calculations for the geometry and operation conditions of the WASA pellet generator are presented and discussed. We have found that for every given pellet size, there is a set of operation parameters where the efficiency of the WASA hydrogen pellet target operation is considerably increased. Moreover, the results of presented computer simulations clearly show that the future PANDA pellet target setup can be realized with the use of much smaller (and cheaper) vacuum pumps than those used at present in the WASA hydrogen pellet target. To qualitatively improve the PANDA hydrogen pellet target performance we have proposed the use of a novel flow focusing method of Ganan-Calvo and Barreto (1997,1999) combined with the use of conventional vacuum injection capillary. Possibilities of this approach for the PANDA pellet target production have been also explored by means of computer simulations. The results of these simulations show that the use of this new approach looks very promising and in particular, there is no need here to use of expensive ultra-pure hydrogen to prevent nozzle clogging or freezing up due to impurities and it will allow simple, fast, smooth and a wide range of change of pellet sizes in accordance with requirements of different experiments at the PANDA detector. In this article we also propose and describe the idea of a new technique to break up a liquid microjet into microdroplets using a process of liquid jet evaporation under pulsed laser beam irradiation. This technique should be experimentally checked before it may be used in the design of the future PANDA pellet target setup.

  16. Numerical investigations of the WASA pellet target operation and proposal of a new technique for the PANDA pellet target

    International Nuclear Information System (INIS)

    Varentsov, Victor L.

    2011-01-01

    The conventional nozzle vibration technique of the hydrogen micro-droplet generation that is supposed to be used for internal pellet target production for the future PANDA experiment at the international FAIR facility in Darmstadtfor is described. The operation of this technique has been investigated by means of detailed computer simulations. Results of calculations for the geometry and operation conditions of the WASA pellet generator are presented and discussed. We have found that for every given pellet size, there is a set of operation parameters where the efficiency of the WASA hydrogen pellet target operation is considerably increased. Moreover, the results of presented computer simulations clearly show that the future PANDA pellet target setup can be realized with the use of much smaller (and cheaper) vacuum pumps than those used at present in the WASA hydrogen pellet target. To qualitatively improve the PANDA hydrogen pellet target performance we have proposed the use of a novel flow focusing method of Ganan-Calvo and Barreto (1997,1999) combined with the use of conventional vacuum injection capillary. Possibilities of this approach for the PANDA pellet target production have been also explored by means of computer simulations. The results of these simulations show that the use of this new approach looks very promising and in particular, there is no need here to use of expensive ultra-pure hydrogen to prevent nozzle clogging or freezing up due to impurities and it will allow simple, fast, smooth and a wide range of change of pellet sizes in accordance with requirements of different experiments at the PANDA detector. In this article we also propose and describe the idea of a new technique to break up a liquid microjet into microdroplets using a process of liquid jet evaporation under pulsed laser beam irradiation. This technique should be experimentally checked before it may be used in the design of the future PANDA pellet target setup.

  17. Study on thermal-hydraulic behavior in supersonic steam injector

    International Nuclear Information System (INIS)

    Abe, Yutaka; Fukuichi, Akira; Kawamoto, Yujiro; Iwaki, Chikako; Narabayashi, Tadashi; Mori, Michitsugu; Ohmori, Shuichi

    2007-01-01

    Supersonic steam injector is the one of the most possible devices aiming at simplifying system and improving the safety and the credibility for next-generation nuclear reactor systems. The supersonic steam injector has dual functions of a passive jet pump without rotating machine and a compact and high efficiency heat exchanger, because it is operated by the direct contact condensation between supersonic steam and subcooled water jet. It is necessary to clarify the flow behavior in the supersonic steam injector which is governed by the complicated turbulent flow with a great shear stress of supersonic steam. However, in previous study, there is little study about the turbulent heat transfer and flow behavior under such a great shear stress at the gas-liquid interface. In the present study, turbulent flow behavior including the effect of the interface between water jet and supersonic steam is developed based on the eddy viscosity model. Radial velocity distributions and the turbulent heat transfer are calculated with the model. The calculation results are compared with the experimental results done with the transparent steam injector. (author)

  18. Status and performance of PF injector linac

    International Nuclear Information System (INIS)

    Sato, Isamu

    1994-01-01

    PF injector linac has been improved on a buncher section for accelerating of intense electron beam, and reinforced a focusing system of the positron generator linac for the expansion of phase space. In this presentation, I shall report present status and performance of PF injector linac, and discuss its upgrade program for B-factory project. (author)

  19. Engineering problems of future neutral beam injectors

    International Nuclear Information System (INIS)

    Fink, J.

    1977-01-01

    Because there is no limit to the energy or power that can be delivered by a neutral-beam injector, its use will be restricted by either its cost, size, or reliability. Studies show that these factors can be improved by the injector design, and several examples, taken from mirror reactor studies, are given

  20. Commissioning of the RFQ1 injector

    International Nuclear Information System (INIS)

    Arbique, G.M.; Sheikh, J.Y.; Taylor, T.; Birney, L.F.; Davidson, A.D.; Wills, J.S.C.

    1987-01-01

    The RFQ1 accelerator is being developed at Chalk River to test the limits of the cw RFQ technology. A 50 kV injector has been built and is now being commissioned as the first phase of the program. This paper describes some of the innovative features of the RFQ1 injector and reports on initial operating experience

  1. Combustion tests with different pellet qualities

    International Nuclear Information System (INIS)

    Bachs, A.; Dahlstroem, J.E.; Persson, Henrik; Tullin, C.

    1999-05-01

    Eight different pellet qualities with the diameters 6, 8 and 10 mm, from eight different producers has been tested in three pellet burners and two pellet stoves. The objective was to investigate how different diameter affect the emissions of CO, OGC and NO x . Previous experience has indicated that the pellet diameter could have significant importance for the combustion. This was not verified in the study. It showed contradictory that the diameter has a minor effect on the combustion result. The study shows that different combustion equipment give different emission. For e g hydrocarbon emissions the difference is a factor 2.2 between the 'best' and the 'worst' equipment fired on full load. The difference increases to 2.7 with lower load. The choice of fuel has a big importance for the quality of the combustion. For hydrocarbons the emissions could in an extreme situation differ with a factor 25 between 'best' and 'worst' fuel. More normally the difference is about a factor of five. Nitrogen oxide emissions are to a major part related to the nitrogen contents in the fuel. The difference between the 'best' and 'worst' fuel is in the range of a factor two. Tests with the same fuel in different equipment gives a variation of 20-30%. The combustion result depends on both the pellet quality and the equipment and there is no fuel that is good in all equipment. The big variation in combustion results shows that there is a big indifference between fuels used for small scale heating Project report from the program: Small scale combustion of biofuels. 2 refs, 15 figs, 5 tabs

  2. Results of combustion and emissions testing when co-firing blends of binder-enhanced densified refuse-derived fuel (b-dRDF) pellets and coal in a 440 MW{sub e} cyclone fired combustor. Volume 3: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Ohlsson, O.

    1994-07-01

    This report contains the data resulting from the co-firing of b-dRDF pellets and coal in a 440-MW{sub e} cyclone-fired combustor. These tests were conducted under a Collaborative Research and Development Agreement (CRADA). The CRADA partners included the U.S. Department of Energy (DOE), National Renewable Energy Laboratory (NREL), Argonne National Laboratory (ANL), Otter Tail Power Company, Green Isle Environmental, Inc., XL Recycling Corporation, and Marblehead Lime Company. The report is made up of three volumes. This volume contains other supporting information, along with quality assurance documentation and safety and test plans. With this multi-volume approach, readers can find information at the desired level of detail, depending on individual interest or need.

  3. Westinghouse Advanced Doped Pellet - Characteristics and irradiation behavior

    International Nuclear Information System (INIS)

    Backman, K.; Hallstadius, L.; Roennberg, G.

    2009-01-01

    Full text: There are a number of trends in the nuclear power industry, which put additional requirements on the operational flexibility and reliability of nuclear fuel, for example power uprates and longer cycles in order to increase production, higher burnup levels in order to reduce the backend cost of the fuel cycle, and lower goals for activity release from power plant operation. These additional requirements can be addressed by increasing the fuel density, improving the FG retention, improving the PCI resistance and improving the post-failure performance. In order to achieve that, Westinghouse has developed ADOPT (Advanced Doped Pellet Technology) UO 2 fuel containing additions of chromium and aluminium oxides. The additives facilitate pellet densification during sintering, enlarge the pellet grain size, and increase the creep rate. The final manufactured doped pellets reach about 0.5 % higher density within a shorter sintering time and a five times larger grain size compared with standard UO 2 fuel pellets. Fuel rods with ADOPT pellets have been irradiated in several light water reactors (LWRs) since 1999, including two full SVEA Optima2 reloads in 2005. ADOPT pellets has been investigated in pool-side and hot cell Post Irradiation Examinations (PIEs), as well as in a ramp test and a fuel washout test in the Studsvik R2 test reactor. The investigations have identified three areas of improved operational behaviour: Reduced Fission Gas Release (FGR), improved Pellet Cladding Interaction (PCI) performance thanks to increased pellet plasticity and higher resistance against post-failure degradation. The better FGR behaviour of ADOPT has been verified with a pool side FGR gamma measurement performed at 55 MWd/kgU, as well as transient tests in the Studsvik R2 reactor. Creep measurements performed on fresh pellets show that ADOPT has a higher creep rate which is beneficial for the PCI performance. ADOPT has also been part of a high power Halden test (IFA-677). The

  4. Emissions from small scale combustion of pelletized wood fuels

    International Nuclear Information System (INIS)

    Bachs, A.

    1998-01-01

    Combustion of wood pellets in small scale heating systems with an effect below 20 kW has increased. During the winter season 1995/96 1500 small plants for heating houses are estimated to be in operation. Stack emissions from three pellet burners and two pellet stoves have been studied at laboratory. Different pellet qualities were tested. When the fraction of fines increased also the NO x emissions increased with about 10 %. As reference fuel 8 mm pellets was used. Tests with 6 mm pellets gave, in most cases, significant lower emissions of CO and THC. Eleven stoves, burners and boilers were studied in a field test. The results show that all the plants generally have higher emissions in the field than during conditions when the plants are adjusted with a stack gas monitoring instrument. A conclusion is that it is difficult for the operator to adjust the plant without a monitoring instrument. The emissions from the tested plants give an estimation of stack gas emissions from small scale pellet plants. The difference between the 'best' and 'worst' technologies is big. The span of emissions with the best technology to the worst is given below. The interval is concerning normal combustion . During abnormal conditions the emissions are on a significant higher level: * CO 80-1 000 mg/MJ; * Tar 0,3-19 mg/MJ; * THC (as methane equivalents) 2-100 mg/MJ; * NO x 50-70 mg/W;, and * Dust emissions 20-40 mg/MJ. Emissions from pellets heating are lower than from wood combustion and the best technology is close to the emission from oil burners. Wood and pellets have the same origin but the conditions to burn them in an environmental friendly way differ. Combustion of pellets could be improved through improved control of the air and fuel ratio that will create more stable conditions for the combustion

  5. Manufacture, delivery and marketing of wood pellets

    International Nuclear Information System (INIS)

    Huhtanen, T.

    2001-01-01

    Wood pellet is a cheap fuel, the use of which can easily bee automated. Pellet heating can be carried out with a stoker or a pellet burner, which can be mounted to oil and solid fuels boiler or to solid fuel boilers. Vapo Oy delivers wood pellet to farms and detached houses via Agrimarket stores. Vapo Oy delivers pellets to large real estates, municipalities, industry, greenhouses and power plants directly as bulk. The pellets are delivered either by trailers or lorries equipped with fan-operated unloaders. The use of wood pellets is a suitable fuel especially for real estates, the boiler output of which is 20 - 1000 kW. Vapo Oy manufactures wood pellets of cutter chips, grinding dust and sawdust. The raw material for Ilomantsi pellet plant is purchased from the province of North Karelia. The capacity of pelletizing plant is 45 000 t of pellets per year, half of which is exported mainly to Sweden and Denmark

  6. Studies on a burner used biomass pellets as fuel. Performance of a spiral vortex pellet burner

    Energy Technology Data Exchange (ETDEWEB)

    Iwao, Toshio

    1987-12-21

    In order to develop a small size burner with high performance using biomass pellets fuel substitute for fuel oil, the burning performance of a spiral vortex pallet burner has been studied. An experimental equipment for the pellet burning is made up of a fuel supply unit, combustion chamber and a furnace. The used woody pellet is made of mixed sawdust and bark; with water content of 10.29%, particle diameter of 5.5-9mm, length of 5-50mm, and, apparent and real specific gravities are 0.59 and 1.334 respectively. The pellets are sent to bottom of the combustion chamber, spiral vortex combustion are carried out with blown air, the ashes and unburnt residues are discharged to out of combustion chamber with spiral vortex hot gases. As the result, it was clarified that the formation of the burning layers in a burner is required to be in order of the layers of ash, oxidation, reduction and carbonization up to the upper layer for high burning performance, and the formation of the layer is influenced by the condition of sedimentation of pellets in the combustion chamber. In the meanwhile the burning performance of the burner is influenced by the quantity of blast, the rate of feeding, and by the time of pre-heating in the combustion chamber. (23 figs, 5 refs)

  7. An Injector for the CLIC Test Facility (CTF3)

    CERN Document Server

    Braun, H; Rinolfi, Louis; Zhou, F; Mouton, B; Miller, R; Yeremian, A D

    2000-01-01

    The CLIC Test Facility (CTF3) is an intermediate step to demonstrate the technical feasibility of the key concepts of the new RF power source for CLIC. CTF3 will use electron beams with an energy range adjustable from 170 MeV (3.5 A) to 380 MeV (with low current). The injector is based on a thermionic gun followed by a classical bunching system embedded in a long solenoidal field. As an alternative, an RF photo-injector is also being studied. The beam dynamics studies on how to reach the stringent beam parameters at the exit of the injector are presented. Simulations performed with the EGUN code showed that a current of 7 A can be obtained with an emittance less than 10 mm.mrad at the gun exit. PARMELA results are presented and compared to the requested beam performance at the injector exit. Sub-Harmonic Bunchers (SHB) are foreseen, to switch the phase of the bunch trains by 180 degrees from even to odd RF buckets. Specific issues of the thermionic gun and of the SHB with fast phase switch are discussed.

  8. An Injector for the CLIC Test Facility (CTF3)

    International Nuclear Information System (INIS)

    Miller, Roger H.

    2001-01-01

    The CLIC Test Facility (CTF3) is an intermediate step to demonstrate the technical feasibility of the key concepts of the new RF power source for CLIC. CTF3 will use electron beams with an energy range adjustable from 170 MeV (3.5 A) to 380 MeV (with low current). The injector is based on a thermionic gun followed by a classical bunching system embedded in a long solenoidal field. As an alternative, an RF photo-injector is also being studied. The beam dynamics studies on how to reach the stringent beam parameters at the exit of the injector are presented. Simulations performed with the EGUN code showed that a current of 7 A can be obtained with an emittance less than 10 mm.mrad at the gun exit. PARMELA results are presented and compared to the requested beam performance at the injector exit. Sub-Harmonic Bunchers (SHB) are foreseen, to switch the phase of the bunch trains by 180 degrees from even to odd RF buckets. Specific issues of the thermionic gun and of the SHB with fast phase switch are discussed

  9. An injector for the CLIC test Facility (CTF3)

    CERN Document Server

    Braun, Hans-Heinrich; Rinolfi, L.; Zhou, F.; Mouton, B.; Miller, R.; Yeremian, D.

    2008-01-01

    The CLIC Test Facility (CTF3) is an intermediate step to demonstrate the technical feasibility of the key concepts of the new RF power source for CLIC. CTF3 will use electron beams with an energy range adjustable from 170 MeV (3.5 A) to 380 MeV (with low current). The injector is based on a thermionic gun followed by a classical bunching system embedded in a long solenoidal field. As an alternative, an RF photo-injector is also being studied. The beam dynamics studies on how to reach the stringent beam parameters at the exit of the injector are presented. Simulations performed with the EGUN code showed that a current of 7 A can be obtained with an emittance less than 10 mm.mrad at the gun exit. PARMELA results are presented and compared to the requested beam performance at the injector exit. Sub-Harmonic Bunchers (SHB) are foreseen, to switch the phase of the bunch trains by 180 degrees from even to odd RF buckets. Specific issues of the thermionic gun and of the SHB with fast phase switch are discussed.

  10. Study on the characteristics of the supersonic steam injector

    International Nuclear Information System (INIS)

    Abe, Yutaka; Shibayama, Shunsuke

    2014-01-01

    Steam injector is a passive jet pump which operates without power source or rotating machinery and it has high heat transfer performance due to the direct-contact condensation of supersonic steam flow onto subcooled water jet. It has been considered to be applied to the passive safety system for the next-generation nuclear power plants. The objective of the present study is to clarify operating mechanisms of the steam injector and to determine the operating ranges. In this study, temperature and velocity distribution in the mixing nozzle as well as flow directional pressure distribution were measured. In addition, flow structure in whole of the injector was observed with high-speed video camera. It was confirmed that there were unsteady interfacial behavior in mixing nozzle which enhanced heat transfer between steam flow and water jet with calculation of heat transfer coefficient. Discharge pressure at diffuser was also estimated with a one-dimensional model proposed previously. Furthermore, it was clarified that steam flow did not condense completely in mixing nozzle and it was two-phase flow in throat and diffuser, which seemed to induce shock wave. From those results, several discussions and suggestions to develop a physical model which predicts the steam injectors operating characteristics are described in this paper

  11. Beam dynamics simulation of the S-DALINAC injector section

    Energy Technology Data Exchange (ETDEWEB)

    Franke, Sylvain; Ackermann, Wolfgang; Weiland, Thomas [Institut fuer Theorie Elektromagnetischer Felder, Technische Universitaet Darmstadt, Darmstadt (Germany)

    2013-07-01

    In order to extend the experimental possibilities at the superconducting electron linear accelerator S-DALINAC a new polarized gun has recently been installed in addition to the well-established thermionic electron source. Beside the two electron sources the injector section consists of several short quadrupole triplets, an alpha magnet, a Wien filter and a chopper/prebuncher system. The setup of these components differs depending on whether bunched polarized electrons with kinetic energy in the 100 keV range are supplied by the polarized source or whether a continuous unpolarized 250 keV electron beam is extracted from the thermionic gun. The electrons pass through the injector at a relatively low energy and therefore are very sensitive to the beam forming elements in this section. Thus, a proper knowledge of the particle distribution at the exit of the injector section is essential for the quality of any simulation of the subsequent accelerator parts. In this contribution first numerical beam dynamics simulation results of the S-DALINAC injector setup are discussed.

  12. Impact of biodiesel blend on injector deposit formation

    International Nuclear Information System (INIS)

    Liaquat, A.M.; Masjuki, H.H.; Kalam, M.A.; Rizwanul Fattah, I.M.

    2014-01-01

    Continued legislative pressure to reduce exhaust emissions from CI (compression ignition) has resulted in the development of advanced fuel injection equipment. This advanced injection system produces higher temperatures and pressures at the injector tip, where deposit formation is initiated. In this research, an endurance test was carried out for 250 h on 2 fuel samples; DF (diesel fuel) as baseline fuel and JB20 (20% jatropha biodiesel and 80% DF) in a single-cylinder CI engine. The effects of JB20 on injector nozzle deposits, engine lubricating oil, and fuel economy and exhaust emissions were investigated during the endurance test. According to the results of the investigation, visual inspection showed some deposit accumulation on injectors for both fuel samples. SEM (scanning electron microscopy) and EDX (energy dispersive X-ray spectroscopy) analysis showed greater carbon deposits on and around the injector tip for JB20 compared to the engine running with DF. Similarly, lubricating oil analysis presented excessive wear metal concentrations and decreased viscosity values when the engine was fueled with JB20. Finally, fuel economy and emission results during the endurance test showed higher BSFC (brake specific fuel consumption) and NO x emissions, and lower HC (hydrocarbons) and CO (carbon monoxide) emissions, for the JB20 blend compared to DF. - Highlights: • Endurance test for 250 h on 2 fuel samples; diesel fuel and JB20. • Investigation on effects of JB20 on the injector deposits and exhaust emissions. • Lubricating oil analysis during endurance test. • SEM (scanning electron microscopy) analysis. • EDX (energy dispersive X-ray spectroscopy) analysis

  13. Linear resonance acceleration of pellets

    International Nuclear Information System (INIS)

    Mills, R.G.

    1978-01-01

    A possible requirement for the acceleration of macroscopic pellets to velocities exceeding 10 4 meters per second implies the development of new apparatus. A satisfactory approach might be the linear resonance accelerator. Such apparatus would require the charging of pellets to very high values not yet demonstrated. The incompatibility of phase stability with radial stability in these machines may require abandoning phase stability and adopting feedback control of the accelerating voltage to accommodate statistical fluctuations in the charge to mass ratio of successive pellets

  14. Influence of burner form and pellet type on domestic pellet boiler performance

    Science.gov (United States)

    Rastvorov, D. V.; Osintsev, K. V.; Toropov, E. V.

    2017-10-01

    The study presents combustion and emission results obtained using two serial pellet boilers of the same heating capacity 40 kW. These boilers have been designed by producers for domestic conditions of exploitation. The principal difference between boilers was the type of the burner. The study concerns the efficiency and ecological performance difference between burners of circular and rectangular forms. The features of the combustion process in both types of burners were studied when boiler operated with different sorts of pellets. The results suggest that the burner of circular form excels the rectangular form burner. However, there is some difference of NOx emission between circular and rectangular burners.

  15. Hybrid pellets: an improved concept for fabrication of nuclear fuel

    International Nuclear Information System (INIS)

    Matthews, R.B.; Hart, P.E.

    1979-09-01

    The feasibility of fabricating fuel pellets using gel-derived microspheres as press feed was evaluated. By using gel-derived microspheres as press feed, the potential exists for eliminating dusty operations like milling, slugging, and granulation, from the pelleting process. The free-flowing character of the spheres should also result in limited dust generation during powder transport and pressing operations. The results of this study clearly demonstrate that fuel pellets can be successfully fabricated on a laboratory scale using UO 2 gel microspheres as press feed. Under moderate sintering conditions, 1,500 0 C for 4 h in Ar-4% H 2 , UO 2 pellets with densities up to 96% TD were fabricated. A range of pellet microstructures and densities were achieved depending on sphere forming and calcining conditions. Based on these results, a set of necessary sphere properties are suggested: O/U less than 2.20, crystallite size less than 500 A, specific surface area greater than 8 m 2 /g, and sphere size 200 and 400 μm. Preliminary attempts to fabricate ThO 2 and ThO 2 -UO 2 pellets using microspheres were unsuccessful because the requisite sphere properties were not achieved. Areas requiring additional development include: demonstration of the process on scaled-up equipment suitable for use in a remote fuel fabrication facility and evaluation of the irradiation performance of pellet fuels from gel-spheres

  16. Adsorption of trace metals to plastic resin pellets in the marine environment

    International Nuclear Information System (INIS)

    Holmes, Luke A.; Turner, Andrew; Thompson, Richard C.

    2012-01-01

    Plastic production pellets collected from beaches of south west England contain variable concentrations of trace metals (Cr, Co, Ni, Cu, Zn, Cd and Pb) that, in some cases, exceed concentrations reported for local estuarine sediments. The rates and mechanisms by which metals associate with virgin and beached polyethylene pellets were studied by adding a cocktail of 5 μg L −1 of trace metals to 10 g L −1 pellet suspensions in filtered seawater. Kinetic profiles were modelled using a pseudo-first-order equation and yielded response times of less than about 100 h and equilibrium partition coefficients of up to about 225 ml g −1 that were consistently higher for beached pellets than virgin pellets. Adsorption isotherms conformed to both the Langmuir and Freundlich equations and adsorption capacities were greater for beached pellets than for virgin pellets. Results suggest that plastics may represent an important vehicle for the transport of metals in the marine environment. - Highlights: ► Beached plastic production pellets contain considerable concentrations of trace metals. ► In laboratory experiments trace metals are shown to adsorb to both virgin and beached pellets. ► Metal adsorption is greater on aged pellets. ► Pellets may represent an important vehicle for metal transport in the marine environment. - Trace metals accumulate on plastic resin pellets in the marine environment through adsorption to the polymer and to chemical and biological attritions thereon.

  17. Gas Gun Model and Comparison to Experimental Performance of Pipe Guns Operating with Light Propellant Gases and Large Cryogenic Pellets

    Energy Technology Data Exchange (ETDEWEB)

    Reed, J. R. [University of Tennessee, Knoxville (UTK); Carmichael, J. R. [Fermi National Accelerator Laboratory (FNAL); Gebhart, T. E. [University of Florida, Gainesville; Combs, Stephen Kirk [ORNL; Baylor, Larry R. [ORNL; Rasmussen, David A. [ORNL; Meitner, Steven J. [ORNL; Lyttle, Mark S. [ORNL

    2017-10-01

    Injection of multiple large (~10 to 30 mm diameter) shattered pellets into ITER plasmas is presently part of the scheme planned to mitigate the deleterious effects of disruptions on the vessel components. To help in the design and optimize performance of the pellet injectors for this application, a model referred to as “the gas gun simulator” has been developed and benchmarked against experimental data. The computer code simulator is a Java program that models the gas-dynamics characteristics of a single-stage gas gun. Following a stepwise approach, the code utilizes a variety of input parameters to incrementally simulate and analyze the dynamics of the gun as the projectile is launched down the barrel. Using input data, the model can calculate gun performance based on physical characteristics, such as propellant-gas and fast-valve properties, barrel geometry, and pellet mass. Although the model is fundamentally generic, the present version is configured to accommodate cryogenic pellets composed of H2, D2, Ne, Ar, and mixtures of them and light propellant gases (H2, D2, and He). The pellets are solidified in situ in pipe guns that consist of stainless steel tubes and fast-acting valves that provide the propellant gas for pellet acceleration (to speeds ~200 to 700 m/s). The pellet speed is the key parameter in determining the response time of a shattered pellet system to a plasma disruption event. The calculated speeds from the code simulations of experiments were typically in excellent agreement with the measured values. With the gas gun simulator validated for many test shots and over a wide range of physical and operating parameters, it is a valuable tool for optimization of the injector design, including the fast valve design (orifice size and volume) for any operating pressure (~40 bar expected for the ITER application) and barrel length for any pellet size (mass, diameter, and length). Key design parameters and proposed values for the pellet injectors for

  18. Dependency between removal characteristics and defined measurement categories of pellets

    Science.gov (United States)

    Vogt, C.; Rohrbacher, M.; Rascher, R.; Sinzinger, S.

    2015-09-01

    Optical surfaces are usually machined by grinding and polishing. To achieve short polishing times it is necessary to grind with best possible form accuracy and with low sub surface damages. This is possible by using very fine grained grinding tools for the finishing process. These however often show time dependent properties regarding cutting ability in conjunction with tool wear. Fine grinding tools in the optics are often pellet-tools. For a successful grinding process the tools must show a constant self-sharpening performance. A constant, at least predictable wear and cutting behavior is crucial for a deterministic machining. This work describes a method to determine the characteristics of pellet grinding tools by tests conducted with a single pellet. We investigate the determination of the effective material removal rate and the derivation of the G-ratio. Especially the change from the newly dressed via the quasi-stationary to the worn status of the tool is described. By recording the achieved roughness with the single pellet it is possible to derive the roughness expect from a series pellet tool made of pellets with the same specification. From the results of these tests the usability of a pellet grinding tool for a specific grinding task can be determined without testing a comparably expensive serial tool. The results are verified by a production test with a serial tool under series conditions. The collected data can be stored and used in an appropriate data base for tool characteristics and be combined with useful applications.

  19. NBS-LANL RTM injector installation

    International Nuclear Information System (INIS)

    Wilson, M.A.; Ayres, R.L.; Cutler, R.I.; Lindstrom, E.R.; Martin, E.R.; Mohr, D.L.; Penner, S.; Yoder, N.R.; Young, L.M.

    1983-01-01

    The injector for the NBS-LANL CW racetrack microtron consists of a 100 KeV electron gun and beam transport line followed by a 5 MeV linac. The function of the gun and transport line, which have been installed at NBS, is to provide a chopped and bunched 100 KeV and up to 0.67 mA dc or pulsed beam of very low transverse emittance for matched insertion into the linac. In this paper the authors present both the design and construction details of the 100 KeV system and the results of preliminary beam tests. The tests conducted thus far show the gun and transport system to be performing well within design specifications

  20. Commissioning the Linac Coherent Light Source injector

    Directory of Open Access Journals (Sweden)

    R. Akre

    2008-03-01

    Full Text Available The Linac Coherent Light Source is a SASE x-ray free-electron laser (FEL project presently under construction at SLAC [J. Arthur et al., SLAC-R-593, 2002.]. The injector section, from drive laser and rf photocathode gun through first bunch compressor chicane, was installed in the fall of 2006. The initial system commissioning with an electron beam was completed in August of 2007, with the goal of a 1.2-micron emittance in a 1-nC bunch demonstrated. The second phase of commissioning, including second bunch compressor and full linac, is planned for 2008, with FEL commissioning in 2009. We report experimental results and experience gained in the first phase of commissioning, including the photocathode drive laser, rf gun, photocathode, S-band and X-band rf systems, first bunch compressor, and the various beam diagnostics.

  1. String cavitation formation inside fuel injectors

    Science.gov (United States)

    Reid, B. A.; Gavaises, M.; Mitroglou, N.; Hargrave, G. K.; Garner, C. P.; McDavid, R. M.

    2015-12-01

    The formation of vortex or ‘string’ cavitation has been visualised at pressures up to 2000 bar in an automotive-sized optical diesel fuel injector nozzle. The multi-hole nozzle geometry studied allowed observation of the hole-to-hole vortex interaction and, in particular, that of a bridging vortex in the sac region between the holes. Above a threshold Reynolds number, their formation and appearance during a 2 ms injection event was repeatable and independent of upstream pressure and cavitation number. In addition, two different hole layouts and threedimensional flow simulations have been employed to describe how, the relative positions of adjacent holes influenced the formation and hole-to-hole interaction of the observed string cavitation vortices, with good agreement between the experimental and simulation results being achieved.

  2. What factors affect the carriage of epinephrine auto-injectors by teenagers?

    Directory of Open Access Journals (Sweden)

    Macadam Clare

    2012-02-01

    Full Text Available Abstract Background Teenagers with allergies are at particular risk of severe and fatal reactions, but epinephrine auto-injectors are not always carried as prescribed. We investigated barriers to carriage. Methods Patients aged 12-18 years old under a specialist allergy clinic, who had previously been prescribed an auto-injector were invited to participate. Semi-structured interviews explored the factors that positively or negatively impacted on carriage. Results Twenty teenagers with food or venom allergies were interviewed. Only two patients had used their auto-injector in the community, although several had been treated for severe reactions in hospital. Most teenagers made complex risk assessments to determine whether to carry the auto-injector. Most but not all decisions were rational and were at least partially informed by knowledge. Factors affecting carriage included location, who else would be present, the attitudes of others and physical features of the auto-injector. Teenagers made frequent risk assessments when deciding whether to carry their auto-injectors, and generally wanted to remain safe. Their decisions were complex, multi-faceted and highly individualised. Conclusions Rather than aiming for 100% carriage of auto-injectors, which remains an ambitious ideal, personalised education packages should aim to empower teenagers to make and act upon informed risk assessments.

  3. Digital Measuring Devices Used for Injector Hydraulic Test

    Directory of Open Access Journals (Sweden)

    S. N. Leontiev

    2015-01-01

    Full Text Available To ensure a high specific impulse of the LRE (liquid-propellant engine chamber it is necessary to have optimally organized combustion of the fuel components. This can be ensured by choosing the optimum geometry of gas-dynamic contour of the LRE combustor, as well as by improving the sputtering processes and mixing the fuel components, for example, by selection of the optimum type, characteristics, and location of injectors on the mixing unit of the chamber.These particular reasons arise the interest in the injector characteristics in terms of science, and technological aspects determine the need for control of underlying design parameters in their manufacture.The objective of this work is to give an experimental justification on used digital measurement instrumentation and research the hydraulic characteristics of injectors.To determine injector parameters most widely were used the units with sectional collectors. A technique to control injector parameters using the sectional collectors involves spraying the liquid by injector at a given pressure drop on it for a certain time (the longer, the higher the accuracy and reliability of the results and then determining the amount of liquid in each section to calculate the required parameters of injector.In this work the liquid flow through the injector was determined by high-precision flowmeters FLONET FN2024.1 of electromagnetic type, which have very high metrological characteristics, in particular a flow rate error does not exceed 0.5% in a range of water flow from Qmin= 0.0028 l/s to Qmax Qmax = 0.28 l/s. To determine the coefficient of uneven spray were used differential pressure sensors DMD 331-ASLX of company "DB Sensors RUS", which have an error of 0.075% with a range of differential pressure 0 ... 5 kPa. Measuring complex MIC-200 of company "NPP Measure" and WinPos software for processing array information provided entry, recording, and processing of all the data of the experiment.In this

  4. Handling of Deuterium Pellets for Plasma Refuelling

    DEFF Research Database (Denmark)

    Jensen, Peter Bjødstrup; Andersen, Verner

    1982-01-01

    The use of a guide tube technique to inject pellets in pellet-plasma experiments is described. The effect of the guide tube on the mass and speed of a slowly moving pellet ( nu approximately 150 m s-1) is negligible. To improve the divergence in trajectories of the pellets on leaving the guide tube...

  5. Passive system with steam-water injector for emergency supply of NPP steam generators

    International Nuclear Information System (INIS)

    Il'chenko, A.G.; Strakhov, A.N.; Magnitskij, D.N.

    2009-01-01

    The calculation results of reliability indicators of emergency power supply system and emergency feed-water supply system of serial WWER-1000 unit are presented. To ensure safe water supply to steam generators during station blackout it was suggested using additional passive emergency feed-water system with a steam-water injector working on steam generators dump steam. Calculated analysis of steam-water injector operating capacity was conducted at variable parameters of steam at the entrance to injector, corresponding to various moments of time from the beginning of steam-and-water damping [ru

  6. On-line control system for electron injector based on autoemission cathode

    International Nuclear Information System (INIS)

    Egorov, N.V.; Karpov, A.G.; Ovsyannikov, D.A.; Prudnikov, A.P.

    1987-01-01

    An original on-line system of control of electron injector parameters on the base of an autoemission cathode is described. The system includes hardware (analog-to-digital and graphical displays, a printer, a magnetic disc memory a plotter) and data control and readout equipment. A high-voltage power source of the 'RACE' is controlled by digital measuring devices connected with a computer data via a special matching device. Software includes servicing subroutines for injector controls and those permitting to display, plot and print results. The main operating program functioning in the interactive mode enables to specify the injector operating conditions and check its characteristics

  7. ILSE-ESQ injector scaled experiment

    International Nuclear Information System (INIS)

    Henestroza, E.; Eylon, S.; Yu, S.; Grote, D.

    1993-05-01

    A 2 MeV, 800 mA, K + injector for the Heavy Ion Fusion Induction Linac Systems Experiments (ISLE) is under development at LBL. It consists of a 500 keV-1MeV diode preinjector followed by an electrostatic quadrupole accelerator (ESQ). One of the key issues for the ESQ centers around the control of beam aberrations due to the ''energy effect'': in a strong electrostatic quadrupole field, ions at beam edge will have energies very different from those on the axis. The resulting kinematic distortions lead to S-shaped phase spaces, which, if uncorrected, will lead eventually to emittance growth. These beam aberrations can be minimized by increasing the injection energy and/or strengthening the beam focusing. It may also be possible to compensate for the ''energy effect'' by proper shaping of the quadrupoles electrodes. In order to check the physics of the ''energy effect'' of the ESQ design a scaled experiment has been designed that will accommodate the parameters of the source, as well as the voltage limitations, of the Single Beam Transport Experiment (SBTE). Since the 500 keV pre-injector delivers a 4 cm converging beam, a quarter-scale experiment will fit the 1 cm converging beam of the SBTE source. Also, a 10 mA beam in SBTE, and the requirement of equal perveance in both systems, forces all the voltages to scale down by a factor 0.054. Results from this experiment and corresponding 3D PIC simulations will be presented

  8. Physics of inertial confinement pellets

    International Nuclear Information System (INIS)

    Mead, W.C.

    1979-01-01

    An overview of inertial confinement fusion pellet physics is given. A discussion is presented of current estimated ICF driver requirements and a couple of pellet examples. The physics of driver/plasma coupling for two drivers which are being considered, namely a laser driver and a heavy ion accelerator driver, is described. Progress towards inertial confinement fusion that has been made using laser drivers in target experiments to date is discussed

  9. Nuclear fuel pellet charging device

    International Nuclear Information System (INIS)

    Komuro, Kojiro.

    1990-01-01

    The present invention concerns a nuclear fuel pellet loading device, in which nuclear fuel pellets are successively charged from an open end of a fuel can while rotating the can. That is, a fuel can sealed at one end with an end plug and opened at the other end is rotated around its pipe axis as the center on a rotationally diriving table. During rotation of the fuel can, nuclear fuel pellets are successively charged by means of a feed rod of a feeding device to the inside of the fuel can. The fuel can is rotated while being supported horizontally and the fuel pellets are charged from the open end thereof. Alternatively, the fuel can is rotated while being supported obliquely and the fuel pellets are charged gravitationally into the fuel can. In this way, the damages to the barrier of the fuel can can be reduce. Further, since the fuel pellets can be charged gravitationally by rotating the fuel can while being supported obliquely, the damages to the barrier can be reduced remarkably. (I.S.)

  10. Electron-beam rocket acceleration of hydrogen pellets

    International Nuclear Information System (INIS)

    Tsai, C.C.; Foster, C.A.; Milora, S.L.; Schechter, D.E.; Whealton, J.H.

    1992-01-01

    A proof-of-principle device for characterizing electron-beam rocket pellet acceleration has been developed and operated during the last few years. Experimental data have been collected for thousands of accelerated hydrogen pellets under a variety of beam conditions. One intact hydrogen pellet was accelerated to a speed of 578 m/s by an electron beam of 10 kV, 0.8 A, and I ms. The collected data reveal the significant finding that the measured bum velocity of bare hydrogen pellets increases with the square of the beam voltage in a way that is qualitatively consistent with the theoretical prediction based on the neutral gas shielding (NGS) model. The measured bum velocity increases with the beam current or power and then saturates at values two to three times greater than that predicted by the NGS model. The discrepancy may result from low pellet strength and large beam-pellet interaction areas. Moreover, this feature may be the cause of the low measured exhaust velocity, which often exceeds the sonic velocity of the ablated gas. Consistent with the NGS model, the measured exhaust velocity increases in direct proportion to the beam current and in inverse proportion to the beam voltage. To alleviate the pellet strength problem, experiments have been performed with the hydrogen ice contained in a lightweight rocket casing or shell. Pellets in such sabots have the potential to withstand higher beam powers and achieve higher thrust-coupling efficiency. Some experimental results are reported and ways of accelerating pellets to higher velocity are discussed

  11. Runaway electron generation during plasma shutdown by killer pellet injection

    International Nuclear Information System (INIS)

    Gal, K; Feher, T; Smith, H; Fueloep, T; Helander, P

    2008-01-01

    Tokamak discharges are sometimes terminated by disruptions that may cause large mechanical and thermal loads on the vessel. To mitigate disruption-induced problems it has been proposed that 'killer' pellets could be injected into the plasma in order to safely terminate the discharge. Killer pellets enhance radiative energy loss and thereby lead to rapid cooling and shutdown of the discharge. But pellets may also cause runaway electron generation, as has been observed in experiments in several tokamaks. In this work, runaway dynamics in connection with deuterium or carbon pellet-induced fast plasma shutdown is considered. A pellet code, which calculates the material deposition and initial cooling caused by the pellet is coupled to a runaway code, which determines the subsequent temperature evolution and runaway generation. In this way, a tool has been created to test the suitability of different pellet injection scenarios for disruption mitigation. If runaway generation is avoided, the resulting current quench times are too long to safely avoid large forces on the vessel due to halo currents

  12. Apparatus for loading fuel pellets in fuel rods

    International Nuclear Information System (INIS)

    Tedesco, R.J.

    1976-01-01

    An apparatus is disclosed for loading fuel pellets into fuel rods for a nuclear reactor including a base supporting a table having grooves therein for holding a multiplicity of pellets. Multiple fuel rods are placed in alignment with grooves in the pellet table and a guide member channels pellets from the table into the corresponding fuel rods. To effect movement of pellets inside the fuel rods without jamming, a number of electromechanical devices mounted on the base have arms connected to the lower surface of the fuel rod table which cyclically imparts a reciprocating arc motion to the table for moving the fuel pellets longitudinally of and inside the fuel rods. These electromechanical devices include a solenoid having a plunger therein connected to a leaf type spring, the arrangement being such that upon energization of the solenoid coil, the leaf spring moves the fuel rod table rearwardly and downwardly, and upon deenergization of the coil, the spring imparts an upward-forward movement to the table which results in physical displacement of fuel pellets in the fuel rods clamped to the table surface. 8 claims, 6 drawing figures

  13. Introducing wood pellet fuel to the UK

    Energy Technology Data Exchange (ETDEWEB)

    Cotton, R A; Giffard, A

    2001-07-01

    Technical and non-technical issues affecting the introduction of wood pellet-fired heating to the UK were investigated with the aim of helping to establish a wood pellet industry in the UK. The project examined the growth and status of the industry in continental Europe and North America, reviewed relevant UK standards and legislation, identified markets for pellet heating in the UK, organised workshops and seminars to demonstrate pellet burning appliances, carried out a trial pelletisation of a range of biomass fuels, helped to set up demonstration installations of pellet-fired appliances, undertook a promotional campaign for wood pellet fuel and compiled resource directories for pellet fuel and pellet burning appliances in the UK. The work was completed in three phases - review, identification and commercialisation. Project outputs include UK voluntary standards for wood pellet fuel and combustion appliances, and a database of individuals with an interest in wood pellet fuel.

  14. Multi-shot type pellet injection device

    International Nuclear Information System (INIS)

    Onozuka, Masaki; Uchikawa, Takashi; Kuribayashi, Shitomi.

    1988-01-01

    Purpose: To inject pellets at high speed without melting or sublimating not-injected pellets even at a long pellet injection interval. Constitution: In the conventional multi-shot pellet injection device, the pellet injection interval is set depending on the plasma retention time. However, as the pellet injection interval is increased, not-injected pellets are melted or sublimated due to the introduced heat of acceleration gases supplied from an acceleration gas introduction pipe to give an effect on the dimensional shape of the pellets. In view of the above, a plurality of pellet forming and injection portions each comprising a carrier, an injection pipe and a holder are disposed independently of each other and pellets are formed and injected independently to thereby prevent the thermal effects of the acceleration gases. (Kamimura, M.)

  15. Multi-shot type pellet injection device

    Energy Technology Data Exchange (ETDEWEB)

    Onozuka, Masaki; Uchikawa, Takashi; Kuribayashi, Shitomi.

    1988-07-27

    Purpose: To inject pellets at high speed without melting or sublimating not-injected pellets even at a long pellet injection interval. Constitution: In the conventional multi-shot pellet injection device, the pellet injection interval is set depending on the plasma retention time. However, as the pellet injection interval is increased, not-injected pellets are melted or sublimated due to the introduced heat of acceleration gases supplied from an acceleration gas introduction pipe to give an effect on the dimensional shape of the pellets. In view of the above, a plurality of pellet forming and injection portions each comprising a carrier, an injection pipe and a holder are disposed independently of each other and pellets are formed and injected independently to thereby prevent the thermal effects of the acceleration gases. (Kamimura, M.).

  16. 46 CFR 148.04-21 - Coconut meal pellets (also known as copra pellets).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Coconut meal pellets (also known as copra pellets). 148.04-21 Section 148.04-21 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DANGEROUS... § 148.04-21 Coconut meal pellets (also known as copra pellets). (a) Coconut meal pellets; (1) Must...

  17. 49 CFR 230.57 - Injectors and feedwater pumps.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Injectors and feedwater pumps. 230.57 Section 230... Appurtenances Injectors, Feedwater Pumps, and Flue Plugs § 230.57 Injectors and feedwater pumps. (a) Water.... Injectors and feedwater pumps must be kept in good condition, free from scale, and must be tested at the...

  18. Pellet-plasma interaction studies at ASDEX Upgrade

    International Nuclear Information System (INIS)

    Kocsis, G.; Belonohy, E.; Gal, K.; Kalvin, S.; Veres, G.; Lang, P.T.

    2005-01-01

    to localize the pellet cloud at a certain time (e. g. at the onset of the triggered ELMs). In order to facilitate scaling studies for the next generation of tokamaks, a database containing the decisive parameters of the pellet-plasma interaction was developed using the experimental results obtained at ASDEX Upgrade. Based upon this database a statistical multiple regression analysis is performed using the forward selection method to determine the penetration depth dependence on the main plasma and pellet parameters. Pellet ablation and cloud distribution is simulated by using 1D-Lagrangian cell code which was extended recently by combining it with the simulation of a neutral gas shielding model. Both a simple analytical approximation and a more elaborated quasi 2D approach were developed and validated with the experimental data. In this conference contribution the recent results of these investigations are presented with particular attention to the ELM triggering by pellets and pellet cloud dynamics and drift. (author)

  19. Ablation of a Deuterium Pellet in a Fusion Plasma Viewed as a Stopping Power Problem

    DEFF Research Database (Denmark)

    Chang, C. T.

    1983-01-01

    At present, the most exploited technology to refuel a future fusion reactor is the high speed injection of macroscopic size pellet of solid hydrogen isotopes. The basic idea is that the ablation of a pellet in a fusion reactor is mainly caused by thermal electrons (~ 10 keV) /1/. Due to the low...... sublimation energy of hydrogen isotopes, shortly after the direct impact of the electrons, a dense cloud forms around the pellet. This cloud of ablated material then serves as a stopping medium for the incoming electrons, thus prolongs the pellet life-time. As a result, the deep penetration of the pellet...

  20. CaSO4: Dy + Teflon dosimetric pellets for X, beta and gamma radiation detection

    International Nuclear Information System (INIS)

    Campos, L.L.; Lima, M.F.

    1987-08-01

    CaSO 4 : Dy + TEFLON dosimetric pellets with high sensitivity and low cost for X, beta and gamma radiation monitoring were studied and developed by the Dosimetric Material Production Laboratory of the Radiological Protection Departament and are disposable for sale. The thickness of the pellets are suitable for X, beta and gamma radiation measurements. The dosimetric properties of these pellets were determined and presented in this work. The results show the usefulness of 0,20mm thick pellets for beta radiation monitoring and 0,80mm thick pellets for x and gamma radiation detection. (Author) [pt

  1. A mechanistic investigation on the utilization of lactose as a protective agent for multi-unit pellet systems.

    Science.gov (United States)

    Chin, Wun Chyi; Chan, Lai Wah; Heng, Paul Wan Sia

    2016-03-01

    The effect of lactose particle size on the extent of pellet coat damage was investigated. The extent of pellet coat damage increased linearly with lactose median particle size. It was observed that coated pellets compressed with coarser lactose grades had larger and deeper surface indentations. The surfaces of the pellets compressed with coarser lactose grades were also found to be significantly rougher. Micronized lactose was capable of protecting pellet coats from damage brought about by the presence of coarser lactose particles. The findings suggested a protective effect that micronized lactose conferred to pellet coats was not only through dimensional delimitations but also by higher interparticulate friction and longer particle rearrangement phase. As a result, the pellet volume fraction in the system was reduced. The extent of pellet coat damage was found to escalate when the pellet volume fraction in such system increased beyond a critical value of 0.39.

  2. A Neutral Beam Injector Upgrade for NSTX

    International Nuclear Information System (INIS)

    Stevenson, T.; McCormack, B.; Loesser, G.D.; Kalish, M.; Ramakrishnan, S.; Grisham, L.; Edwards, J.; Cropper, M.; Rossi, G.; Halle, A. von; Williams, M.

    2002-01-01

    The National Spherical Torus Experiment (NSTX) capability with a Neutral Beam Injector (NBI) capable of 80 kiloelectronvolt (keV), 5 Megawatt (MW), 5 second operation. This 5.95 million dollar upgrade reused a previous generation injector and equipment for technical, cost, and schedule reasons to obtain these specifications while retaining a legacy capability of 120 keV neutral particle beam delivery for shorter pulse lengths for possible future NSTX experiments. Concerns with NBI injection included power deposition in the plasma, aiming angles from the fixed NBI fan array, density profiles and beam shine through, orbit losses of beam particles, and protection of the vacuum vessel wall against beam impingement. The upgrade made use of the beamline and cryo panels from the Neutral Beam Test Stand facility, existing power supplies and controls, beamline components and equipment not contaminated by tritium during DT [deuterium-tritium] experiments, and a liquid Helium refrigerator plant to power and cryogenically pump a beamline and three ion sources. All of the Tokamak Fusion Test Reactor (TFTR) ion sources had been contaminated with tritium, so a refurbishment effort was undertaken on selected TFTR sources to rid the three sources destined for the NSTX NBI of as much tritium as possible. An interconnecting duct was fabricated using some spare and some new components to attach the beamline to the NSTX vacuum vessel. Internal vacuum vessel armor using carbon tiles was added to protect the stainless steel vacuum vessel from beam impingement in the absence of plasma and interlock failure. To date, the NBI has operated to 80 keV and 5 MW and has injected requested power levels into NSTX plasmas with good initial results, including high beta and strong heating characteristics at full rated plasma current

  3. FBR pellet fabrication - density and dimensional control

    International Nuclear Information System (INIS)

    Rasmussen, D.E.; Schaus, P.S.

    1982-01-01

    The fuel pellet fabricating experience described in this paper involved pellet processing tests using mixed oxide (PuO 2 -UO 2 ) powders to produce fast breeder reactor (FBR) fuel pellets. Objectives of the pellet processing tests were to establish processing parameters for sintered-to-size fuel pellets to be used in an irradiation test in the Fast Flux Test Facility and to establish baseline fabrication control information. 26 figures, 7 tables

  4. Modelling the role of pellet crack motion in the (r-θ) plane upon pellet-clad interaction in advanced gas reactor fuel

    Energy Technology Data Exchange (ETDEWEB)

    Haynes, T.A. [Centre for Nuclear Engineering & Department of Materials, Imperial College London, Exhibition Rd., London SW7 2AZ (United Kingdom); Ball, J.A. [EDF Energy, Barnett Way, Gloucester GL4 3RS (United Kingdom); Wenman, M.R., E-mail: m.wenman@imperial.ac.uk [Centre for Nuclear Engineering & Department of Materials, Imperial College London, Exhibition Rd., London SW7 2AZ (United Kingdom)

    2017-04-01

    Highlights: • Finite element modelling of pellet relocation in the (r-θ) plane of nuclear fuel. • ‘Soft’ and ‘hard’ PCI have been predicted in a cracked nuclear fuel pellet. • Stress concentration in the cladding ahead of radial pellet cracks is predicted. • The model is very sensitive to the coefficient of friction and power ramp duration. • The model is less sensitive to the number of cracks assumed. - Abstract: A finite element model of pellet fragment relocation in the r-θ plane of advanced gas-cooled reactor (AGR) fuel is presented under conditions of both ‘hard’ and ‘soft’ pellet-clad interaction. The model was able to predict the additional radial displacement of fuel fragments towards the cladding as well as the stress concentration on the inner surface resulting from the azimuthal motion of pellet fragments. The model was subjected to a severe ramp in power from both full power and after a period of reduced power operation; in the former, the maximum hoop stress in the cladding was found to be increased by a factor of 1.6 as a result of modelling the pellet fragment motion. The pellet-clad interaction was found to be relatively insensitive to the number of radial pellet crack. However, it was very sensitive to both the coefficient of friction used between the clad and pellet fragments and power ramp duration.

  5. ALTERNATIVE BINDERS TO BENTONITE FOR IRON ORE PELLETIZING : PART II : EFFECTS ON METALLURGICAL AND CHEMICAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    Osman Sivrikaya

    2014-07-01

    Full Text Available This study was started to find alternative binders to bentonite and to recover the low preheated and fired pellet mechanical strengths of organic binders-bonded pellets. Bentonite is considered as a chemical impurity for pellet chemistry due to acid constituents (SiO2 and Al2O3. Especially addition of silica-alumina bearing binders is detrimental for iron ore concentrate with high acidic content. Organic binders are the most studied binders since they are free in silica. Although they yield pellets with good wet strength; they have found limited application in industry since they fail to give sufficient physical and mechanical strength to preheated and fired pellets. It is investigated that how insufficient preheated and fired pellet strengths can be improved when organic binders are used as binder. The addition of a slag bonding/strength increasing constituent (free in acidic contents into pellet feed to provide pellet strength with the use of organic binders was proposed. Addition of boron compounds such as colemanite, tincal, borax pentahydrate, boric acid together with organic binders such as CMC, starch, dextrin and some organic based binders, into magnetite and hematite pellet mixture was tested. After determining the addition of boron compounds is beneficial to recover the low pellet physical and mechanical qualities in the first part of this study, in this second part, metallurgical and chemical properties (reducibility - swelling index – microstructure – mineralogy - chemical content of pellets produced with combined binders (an organic binder plus a boron compound were presented. The metallurgical and chemical tests results showed that good quality product pellets can be produced with combined binders when compared with the bentonite-bonded pellets. Hence, the suggested combined binders can be used as binder in place of bentonite in iron ore pelletizing without compromising the pellet chemistry.

  6. Effect of Injector Nozzle Holes on Diesel Engine Performance

    OpenAIRE

    Semin,; Yusof, Mohd Yuzri Mohd; Arof, Aminuddin Md; Shaharudin, Daneil Tomo; Ismail, Abdul Rahim

    2010-01-01

    All of the injector nozzle holes have examined and the results are shown that the seven holes nozzle have provided the best burning result for the fuel in-cylinder burned in any different engine speeds and the best burning is in low speed engine. In engine performance effect, all of the nozzles have examined and the five holes nozzle provided the best result in indicted power, indicated torque and ISFC in any different engine speeds.

  7. Blower Gun pellet injection system for W7-X

    Energy Technology Data Exchange (ETDEWEB)

    Dibon, M., E-mail: mathias.dibon@ipp.mpg.de [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Baldzuhn, J.; Beck, M. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Cardella, A. [Lehrstuhl für Nukleartechnik, TU Munich, Boltzmannstr. 15, 85748 Garching (Germany); Köchl, F. [Atominstitut, TU Wien, 1020 Vienna (Austria); Kocsis, G. [Wigner RCP, RMI, P.O. Box 49, H-1525 Budapest-114 (Hungary); Lang, P.T. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Macian-Juan, R. [Lehrstuhl für Nukleartechnik, TU Munich, Boltzmannstr. 15, 85748 Garching (Germany); Ploeckl, B. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Szepesi, T. [Wigner RCP, RMI, P.O. Box 49, H-1525 Budapest-114 (Hungary); Weisbart, W. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany)

    2015-10-15

    Highlights: • Operational principle of the ASDEX Upgrade Blower Gun. • Guiding tube properties for pellet guiding according to the requirements of W7-X. • Diagnostics for the characterization of the injection system. • Experimental procedure to investigate the performance of the Blower Gun. • Results concerning pellet speeds, mass loss, delivery efficiency and exit angle. - Abstract: Foreseen to perform pellet investigations in the new stellarator W7-X, the former ASDEX Upgrade Blower Gun was revised and revitalized. The systems operational characteristics have been surveyed in a test bed. The gun is designed to launch cylindrical pellets with 2 mm diameter and 2 mm length, produced from frozen deuterium D{sub 2}, hydrogen H{sub 2} or a gas mixture consisting of 50% H{sub 2} and 50% D{sub 2}. Pellets are accelerated by a short pulse of pressurized helium propellant gas to velocities in the range of 100–250 m/s. Delivery reliabilities at the launcher exit reach almost unity. The initial pellet mass is reduced to about 50% during the acceleration process. Pellet transfer to the plasma vessel was investigated by a first mock up guiding tube version. Transfer through this S-shaped stainless steel guiding tube (inner diameter 8 mm; length 6 m) containing two 1 m curvature radii was investigated for all pellet types. Tests were performed applying repetition rates from 2 Hz to 50 Hz and propellant gas pressures ranging from 0.1 to 0.6 MPa. For both H{sub 2} and D{sub 2}, low overall delivery efficiencies were observed at slow repetition rates, but stable efficiencies of about 90% above 10 Hz. About 10% of the mass is eroded while flying through the guiding tube. Pellets exit the guiding tube with an angular spread of less than 14°.

  8. Feasibility and application on steam injector for next-generation reactor

    International Nuclear Information System (INIS)

    Narabayashi, Tadashi; Ishiyama, Takenori; Miyano, Hiroshi; Nei, Hiromichi; Shioiri, Akio

    1991-01-01

    A feasibility study has been conducted on steam injector for a next generation reactor. The steam injector is a simple, compact passive device for water injection, such as Passive Core Injection System (PCIS) of Passive Containment Cooling System (PCCS), because of easy start-up without an AC power. An analysis model for a steam injector characteristics has been developed, and investigated with a visualized fundamental test for a two-stage Steam Injector System (SIS) for PCIS and a one-stage low pressure SIS for PCCS. The test results showed good agreement with the analysis results. The analysis and the test results showed the SIS could work over a very wide range of the steam pressure, and is applicable for PCIS or PCCS in the next generation reactors. (author)

  9. Modeling Dynamic Fracture of Cryogenic Pellets

    Energy Technology Data Exchange (ETDEWEB)

    Parks, Paul [General Atomics, San Diego, CA (United States)

    2016-06-30

    This work is part of an investigation with the long-range objective of predicting the size distribution function and velocity dispersion of shattered pellet fragments after a large cryogenic pellet impacts a solid surface at high velocity. The study is vitally important for the shattered pellet injection (SPI) technique, one of the leading technologies being implemented at ORNL for the mitigation of disruption damage on current tokamaks and ITER. The report contains three parts that are somewhat interwoven. In Part I we formulated a self-similar model for the expansion dynamics and velocity dispersion of the debris cloud following pellet impact against a thick (rigid) target plate. Also presented in Part I is an analytical fracture model that predicts the nominal or mean size of the fragments in the debris cloud and agrees well with known SPI data. The aim of Part II is to gain an understanding of the pellet fracturing process when a pellet is shattered inside a miter tube with a sharp bend. Because miter tubes have a thin stainless steel (SS) wall a permanent deformation (dishing) of the wall is produced at the site of the impact. A review of the literature indicates that most projectile impact on thin plates are those for which the target is deformed and the projectile is perfectly rigid. Such impacts result in “projectile embedding” where the projectile speed is reduced to zero during the interaction so that all the kinetic energy (KE) of the projectile goes into the energy stored in plastic deformation. Much of the literature deals with perforation of the target. The problem here is quite different; the softer pellet easily undergoes complete material failure causing only a small transfer of KE to stored energy of wall deformation. For the real miter tube, we derived a strain energy function for the wall deflection using a non-linear (plastic) stress-strain relation for 304 SS. Using a dishing profile identical to the linear Kirchkoff-Love profile (for lack

  10. Study on the pelletizing of sulfate residue with magnetite concentrate in grate-kiln system

    Directory of Open Access Journals (Sweden)

    Shufeng Y.

    2010-01-01

    Full Text Available The experiment on the feasibility of pelletizing with magnetite concentrate and the wasted sulfate residue was carried out, to research the performance of pellet in grate-kiln system and simulate the grate-kiln pelletizing process in the micro-pellet roasting simulation system in laboratory, and the process experiments on preheating and roasting sections were conducted. The results show that in order to obtain pellet with good performance and the magnetite concentrate should be over 20 in mass percent, the suitable pelletizing time is about 10 min and moisture is around 12.5%. Also, according to the process parameters of drying and preheating sections obtained from experiment, it will be successful to use magnetite concentrate and the wasted sulfate residue for pelletizing, which exploits a new way for the use of sulfate residue.

  11. A data mining approach to optimize pellets manufacturing process based on a decision tree algorithm.

    Science.gov (United States)

    Ronowicz, Joanna; Thommes, Markus; Kleinebudde, Peter; Krysiński, Jerzy

    2015-06-20

    The present study is focused on the thorough analysis of cause-effect relationships between pellet formulation characteristics (pellet composition as well as process parameters) and the selected quality attribute of the final product. The shape using the aspect ratio value expressed the quality of pellets. A data matrix for chemometric analysis consisted of 224 pellet formulations performed by means of eight different active pharmaceutical ingredients and several various excipients, using different extrusion/spheronization process conditions. The data set contained 14 input variables (both formulation and process variables) and one output variable (pellet aspect ratio). A tree regression algorithm consistent with the Quality by Design concept was applied to obtain deeper understanding and knowledge of formulation and process parameters affecting the final pellet sphericity. The clear interpretable set of decision rules were generated. The spehronization speed, spheronization time, number of holes and water content of extrudate have been recognized as the key factors influencing pellet aspect ratio. The most spherical pellets were achieved by using a large number of holes during extrusion, a high spheronizer speed and longer time of spheronization. The described data mining approach enhances knowledge about pelletization process and simultaneously facilitates searching for the optimal process conditions which are necessary to achieve ideal spherical pellets, resulting in good flow characteristics. This data mining approach can be taken into consideration by industrial formulation scientists to support rational decision making in the field of pellets technology. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Heavy ion fusion 2 MV injector

    International Nuclear Information System (INIS)

    Yu, S.; Eylon, S.; Henestroza, E.

    1995-04-01

    A heavy-ion-fusion driver-scale injector has been constructed and operated at Lawrence Berkeley Laboratory. The injector has produced 2.3 MV and 950 mA of K + , 15% above original design goals in energy and current. Normalized edge emittance of less than 1 π mm-mr was measured over a broad range of parameters. The head-to-tail energy flatness is less than ± 0.2% over the 1 micros pulse

  13. An introduction to photo-injector design

    International Nuclear Information System (INIS)

    Travier, C.

    1993-07-01

    A quick overview is given of the RF gun basic theory for photo-injectors and of the presently achievable technical parameters thus providing some guidelines to help the designer in his choices. Simple scaling laws and formulas for both beam dynamics and technical parameters are proposed and compared to corresponding values for existing photo-injectors. Various sophisticated schemes used to improve the performances beyond those given by a straightforward approach are reviewed. (author) 65 refs., 11 figs., 3 tabs

  14. A light ion four rod RFQ injector

    International Nuclear Information System (INIS)

    Schempp, A.; Ferch, M.; Klein, H.

    1987-01-01

    The four-rod RFQ has been developed in Frankfurt as an alternative solution for ion injectors. A 202 MHz resonator has been built with design parameters taken from the HERA injector (18keV-750keV, 20mA H - ). Properties of this structure are described and applications as light ion accelerator for particles from an EBIS ion source are discussed

  15. On the pelletizing of sulfide molybdenite concentrate

    International Nuclear Information System (INIS)

    Palant, A.A.

    2007-01-01

    Investigation results are discussed on the process of pelletizing with the use of various binders (water, syrup, sulfite-alcoholic residue and bentonite) for flotation sulfide molybdenite concentrate (∼84 % MoS 2 ) of the Mongolian deposit. It is established that with the use of syrup rather strong pellets (>300 g/p) of desired size (2-3 mm) can be obtained at a binder flowrate of 1 kg per 100 kg of concentrate. The main advantage of using syrup instead of bentonite lies in the fact that in this instance no depletion of a molybdenum calcine obtained by oxidizing roasting of raw ore takes place due to syrup complete burning out. This affects positively subsequent hydrometallurgical conversion because of decreasing molybdenum losses with waste cakes [ru

  16. ENERGY CORRECTION FOR HIGH POWER PROTON/H MINUS LINAC INJECTORS.

    Energy Technology Data Exchange (ETDEWEB)

    RAPARIA, D.; LEE, Y.Y.; WEI, J.

    2005-05-16

    High-energy proton/H minus energy (> GeV) linac injector suffer from energy jitter due to RF amplitude and phase stability. Especially in high power injectors this energy jitter result beam losses more than 1 W/m that require for hand on maintenance. Depending upon the requirements for next accelerator in the chain, this energy jitter may or may not require to be corrected. This paper will discuss the sources of this energy jitter, correction schemes with specific examples.

  17. CFD simulations of the diesel jet primary atomization from a multihole injector

    OpenAIRE

    Chasos, Charalambos

    2017-01-01

    [EN] High pressure multi-hole diesel injectors are currently used in direct-injection common-rail diesel engines for the improvement of fuel injection and air/fuel mixing, and the overall engine performance. The resulting spray injection characteristics are dictated by the injector geometry and the injection conditions, as well as the ambient conditions into which the liquid is injected. The main objective of the present study was to design a high pressure multi-hole diesel inject...

  18. Microwave proton source development for a high-current linac injector

    International Nuclear Information System (INIS)

    Sherman, J.; Bolme, G.; Geisik, C.

    1995-01-01

    Powerful CW proton linear accelerators (100-mA at 0.5--1.0 GeV) are being proposed for spallation neutron-source applications. A 75-keV, 110-mA dc proton injector using a microwave ion source is being tested for these applications. It has achieved 80-keV, 110-mA hydrogen-ion-beam operation. Video and dc beam-current toroid diagnostics are operational, and an EPICS control system is also operational on the 75-keV injector. A technical base development program has also been carried out on a 50-keV injector obtained from Chalk River Laboratories, and it includes low-energy beam transport studies, ion source lifetime tests, and proton-fraction enhancement studies. Technical base results and the present status of the 75-keV injector will be presented

  19. The latest development of EAST neutral beam injector

    International Nuclear Information System (INIS)

    Hu Chundong; Xu Yongjian

    2014-01-01

    As the first full superconducting non-circular cross section Tokomak in the world, EAST is used to explore the forefront physics and engineering issues on the construction of Tokomak fusion reactor. Neutral beam injection has been recognized as one of the most effective means for plasma heating. According to the research plan of the EAST physics experiment, a set of neutral beam injector (4∼8 MW, 10∼100 s)will be built and operational in 2014. The paper presents the latest development of EAST neutral beam injector and the latest experiment results of long pulse beam extraction and high power beam extraction are reported, those results show that all targets reach or almost reach the design targets. All these will lay a solid foundation for the achievement of plasma heating and current drive for EAST in 2014. (authors)

  20. Review of hydrogen pellet injection technology for plasma fueling applications

    International Nuclear Information System (INIS)

    Milora, S.L.

    1989-01-01

    In the past several years, steady progress has been made worldwide in the development of high-speed hydrogen pellet injectors for fueling magnetically confined plasmas. Several fueling systems based on the conventional pneumatic and centrifuge acceleration concepts have been put into practice on a wide variety of toroidal plasma confinement devices. Long-pulse fueling has been demonstrated in the parameter range 0.8--1.3 km/s, for pellets up to 6 mm in diameter, and at delivery rates up to 40 Hz. Conventional systems have demonstrated the technology to speeds approaching 2 km/s, and several more exotic accelerator concepts are under development to meet the more demanding requirements of the next generation of reactor-grade plasmas. These include a gas gun that can operate in tritium, the two-stage light gas gun, electrothermal guns, electromagnetic rail guns, and an electron-beam-driven thruster. Although these devices are in various stages of development, velocities of 3.8 km/s have already been achieved with two-stage light gas guns, and the prospects for attaining 5 km/s in the near future appear good

  1. Radiation-induced grafting of styrene on polypropylene pellets

    International Nuclear Information System (INIS)

    Souza, Camila P.; Ferreira, Henrique P.; Parra, Duclerc F.; Lugao, Ademar B.

    2009-01-01

    The changes of radiation-induced in polypropylene (PP) pellets exposed to gamma irradiation in inert atmosphere were investigated in correlation with the applied doses (10 and 50 kGy). Also, results from the grafting of styrene onto PP pellets using simultaneous irradiation at the same doses are presented. The grafting reaction was carried out using toluene as solvent, under nitrogen atmosphere and at room temperature. The properties of the irradiated and grafted PP pellets were studied using Melt Flow Index, thermal analysis (TG and DSC), and ATR-IR. The degree of grafting (DOG) for the grafted pellets was gravimetrically determined. The results showed that radiation-induced graft polymerization on pellets were successfully obtained and the influence of dose irradiated did not change the thermal properties in spite of the increase in the MFI and consequently this increase in the viscosity results an decrease the molecular mass. The MFI for grafted pellets was not achievable because the high degree of viscosity of polymer, even arising the test temperature, the polymer was not flow enough. (author)

  2. Implementation of an iron ore green pellet on-line size analyser at the QCMC pelletizing plant

    International Nuclear Information System (INIS)

    Bouajila, A.; Boivin, J.-A.; Ouellet, G.; Beaudin, S.

    1999-01-01

    This paper describes work into the design, implementation and performance evaluation of a 3D-image analysis system at the QCMC pelletizing plant. First, the measurement system is reviewed. Second, the ability of the system to achieve reliable, on-line results on a moving conveyor belt is presented and discussed. The problem of segregation caused by disk classification is particularly addressed, as it hinders full size distribution estimation from the top layer. Finally, pelletizing disk controllability is investigated. (author)

  3. Diagnostics Neutral Beam Injector at the TCV Tokamak

    International Nuclear Information System (INIS)

    Mlynar, J.; Shukaev, A.N.; Bosshard, P.; Duval, B.P.; Ivanov, A.A.; Kollegov, M.; Kolmogorov, V.V.; Llobet, X.; Pitts, R.A.; Weisen, H.

    2001-10-01

    Within this report we summarize the technical and experimental effort made on diagnostics neutral beam injector (DNBI) which was installed at tokamak TCV last year. Basic components of DNBI are reviewed, its remote control is presented in more detail. Profile and attenuation studies are referred to. First experimental results obtained with DNBI, which led to a decision to upgrade the machine, are discussed in the last section. (author)

  4. Prototype ion source for JT-60 neutral beam injectors

    International Nuclear Information System (INIS)

    Akiba, M.

    1981-01-01

    A prototype ion source for JT-60 neutral beam injectors has been fabricated and tested. Here, we review the construction of the prototype ion source and report the experimental results about the source characteristics that has been obtained at this time. The prototype ion source is now installed at the prototype unit of JT-60 neutral beam injection units and the demonstration of the performances of the ion source and the prototype unit has just started

  5. Main injector synchronous timing system

    International Nuclear Information System (INIS)

    Blokland, W.; Steimel, J.

    1998-01-01

    The Synchronous Timing System is designed to provide sub-nanosecond timing to instrumentation during the acceleration of particles in the Main Injector. Increased energy of the beam particles leads to a small but significant increase in speed, reducing the time it takes to complete a full turn of the ring by 61 nanoseconds (or more than 3 rf buckets). In contrast, the reference signal, used to trigger instrumentation and transmitted over a cable, has a constant group delay. This difference leads to a phase slip during the ramp and prevents instrumentation such as dampers from properly operating without additional measures. The Synchronous Timing System corrects for this phase slip as well as signal propagation time changes due to temperature variations. A module at the LLRF system uses a 1.2 Gbit/s G-Link chip to transmit the rf clock and digital data (e.g. the current frequency) over a single mode fiber around the ring. Fiber optic couplers at service buildings split off part of this signal for a local module which reconstructs a synchronous beam reference signal. This paper describes the background, design and expected performance of the Synchronous Timing System. copyright 1998 American Institute of Physics

  6. Main injector synchronous timing system

    International Nuclear Information System (INIS)

    Blokland, Willem; Steimel, James

    1998-01-01

    The Synchronous Timing System is designed to provide sub-nanosecond timing to instrumentation during the acceleration of particles in the Main Injector. Increased energy of the beam particles leads to a small but significant increase in speed, reducing the time it takes to complete a full turn of the ring by 61 nanoseconds (or more than 3 rf buckets). In contrast, the reference signal, used to trigger instrumentation and transmitted over a cable, has a constant group delay. This difference leads to a phase slip during the ramp and prevents instrumentation such as dampers from properly operating without additional measures. The Synchronous Timing System corrects for this phase slip as well as signal propagation time changes due to temperature variations. A module at the LLRF system uses a 1.2 Gbit/s G-Link chip to transmit the rf clock and digital data (e.g. the current frequency) over a single mode fiber around the ring. Fiber optic couplers at service buildings split off part of this signal for a local module which reconstructs a synchronous beam reference signal. This paper describes the background, design and expected performance of the Synchronous Timing System

  7. The LHC Lead Injector Chain

    CERN Document Server

    Beuret, A; Blas, A; Burkhardt, H; Carli, Christian; Chanel, M; Fowler, A; Gourber-Pace, M; Hancock, S; Hourican, M; Hill, C E; Jowett, John M; Kahle, K; Küchler, D; Lombardi, A M; Mahner, E; Manglunki, Django; Martini, M; Maury, S; Pedersen, F; Raich, U; Rossi, C; Royer, J P; Schindl, Karlheinz; Scrivens, R; Sermeus, L; Shaposhnikova, Elena; Tranquille, G; Vretenar, Maurizio; Zickler, T

    2004-01-01

    A sizeable part of the LHC physics programme foresees lead-lead collisions with a design luminosity of 1027 cm-2 s-1. This will be achieved after an upgrade of the ion injector chain comprising Linac3, LEIR, PS and SPS machines [1,2]. Each LHC ring will be filled in 10 min by almost 600 bunches, each of 7×107 lead ions. Central to the scheme is the Low Energy Ion Ring (LEIR) [3,4], which transforms long pulses from Linac3 into high-brilliance bunches by means of multi-turn injection, electron cooling and accumulation. Major limitations along the chain, including space charge, intrabeam scattering, vacuum issues and emittance preservation are highlighted. The conversion from LEAR (Low Energy Antiproton Ring) to LEIR involves new magnets and power converters, high-current electron cooling, broadband RF cavities, and a UHV vacuum system with getter (NEG) coatings to achieve a few 10-12 mbar. Major hardware changes in Linac3 and the PS are also covered. An early ion scheme with fewer bunches (but each at nominal...

  8. The light-ion injector

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    In an extensive field mapping program the magnetic fields of the main coils and various pole-gap coils of the light-ion injector (SPC1) were measured. As a further test, the measured field maps were used to calculate the excitation currents through the various coils for a specific field shape. Orbit calculations, based on the electric potential fields measured is the electrolytic tank on the 3:1 scale model of the central region, made it possible to optimise the ion-source position, improve the axial focussing of the beam and specify an approximate position for the second axial. The coils for the first magnetic channel were manufactured and field measurements with the channel in position in the pole-gap have been performed. The radio-frequency system of SPC1 consists of three main sections, namely resonators, power amplifiers and the control systems. The purpose of the rf-system is to provide the accelerating voltages of up to 70 kV peak in the 8,6 to 26 MHz frequency range, which are required to accelerate the particle beams

  9. Method for distinguishing fuel pellets

    International Nuclear Information System (INIS)

    Sagami, Masaharu; Kurihara, Kunitoshi.

    1978-01-01

    Purpose: To distinguish correctly and efficiently the kind of fuel substance enclosed in a cladding tube. Method: Elements such as manganess 55, copper 65, vanadium 51, zinc 64, scandium 45 and the like, each having a large neutron absorption cross section and discharging gamma rays of inherent bright line spectra are applied to or mixed in fuel pellets of different kinds in uranium enrichment degree, plutonium concentration, burnable poison concentration or the like. These fuel rods are irradiated with neutron beams, and energy spectra of gamma rays discharged upon this occasion are observed to carry out distinguishing of fuel pellets. (Aizawa, K.)

  10. Comparative study of durability test methods for pellets and briquettes

    Energy Technology Data Exchange (ETDEWEB)

    Temmerman, Michaeel; Rabier, Fabienne [Centre wallon de Recherches agronomiques (CRA-W), 146, chaussee de Namur, B-5030, Gembloux (Belgium); Jensen, Peter Daugbjerg [Forest and Landscape, The Royal Veterinary and Agricultural University, Rolighedsvej 23, DK-1958 Frederiksberg C (Denmark); Hartmann, Hans; Boehm, Thorsten [Technologie- und Foerderzentrum fuer Nachwachsende Rohstoffe-TFZ, Schulgasse 18, D-94315 Straubing (Germany)

    2006-11-15

    Different methods for the determination of the mechanical durability (DU) of pellets and briquettes were compared by international round robin tests including different laboratories. The DUs of five briquette and 26 pellet types were determined. For briquettes, different rotation numbers of a prototype tumbler and a calculated DU index are compared. For pellets testing, the study compares two standard methods, a tumbling device according to ASAE S 269.4, the Lignotester according to ONORM M 7135 and a second tumbling method with a prototype tumbler. For the tested methods, the repeatability, the reproducibility and the required minimum number of replications to achieve given accuracy levels were calculated. Additionally, this study evaluates the relation between DU and particle density. The results show for both pellets and briquettes, that the measured DU values and their variability are influenced by the applied method. Moreover, the variability of the results depend on the biofuel itself. For briquettes of DU above 90%, five replications lead to an accuracy of 2%, while 39 replications are needed to achieve an accuracy of 10%, when briquettes of DU below 90% are tested. For pellets, the tumbling device described by the ASAE standard allows to reach acceptable accuracy levels (1%) with a limited number of replications. Finally, for the tested pellets and briquettes no relation between DU and particle density was found. (author)

  11. Effects of feeding corn silage, pelleted, ensiled, or pelleted and ...

    African Journals Online (AJOL)

    2017-09-14

    Sep 14, 2017 ... However, lambs fed CS gained weight 21.3% faster than lambs fed AH (259 versus 213 ... ground, pelleted alfalfa more closely resembles a concentrate feed in terms of particle size. .... Vitamin E, 44 IU/g .... feed to reach their market weight versus 102.5 kg of feed for the lambs fed alfalfa haylage (P <0.01).

  12. Building giant plant for pellets; Bygger gigantanlegg for pellets

    Energy Technology Data Exchange (ETDEWEB)

    Nylund, Hilde Kari

    2008-07-01

    At Averoey outside of Kristiansund, Norway, one of the biggest pellet factories in the world is going to be built. The Norwegian companies Hafslund and Moere og Romsdal Biobrensel are together making an effort in bio energy. A brief presentation of the planned plant is provided

  13. Effects of feeding corn silage, pelleted, ensiled, or pelleted and ...

    African Journals Online (AJOL)

    Two experiments were conducted to evaluate the effects of corn silage (CS) and alfalfa (pelleted (AP), haylage (AH), or combination (APH)) on lamb growth and carcass characteristics. The objective of Experiment 1 (Exp. 1) was to compare AH to CS in lamb feedlot diets on lamb growth and carcass characteristics.

  14. Status of the ATLAS Positive-Ion Injector Project

    International Nuclear Information System (INIS)

    Pardo, R.C.; Benaroya, R.; Billquist, P.J.

    1987-01-01

    The goal of the Argonne Positive Ion Injector project is to replace the ATLAS tandem injector with a facility which will increase the beam currents presently available by a factor of 100 and to make available at ATLAS essentially all beams including uranium. The beam quality expected from the facility will be at least as good as that of the tandem based ATLAS. The project combines two relatively new technologies - the electron cyclotron resonance ion source, which provides high charge state ions at microampere currents, and RF superconductivity which has been shown to be capable of generating accelerating fields as high as 10 MV/m, resulting in an essentially new method of acceleration for low-energy heavy ions. 5 refs., 7 figs., 1 tabs

  15. Evaluation of pesticide adsorption in gas chromatographic injector and column

    Directory of Open Access Journals (Sweden)

    Gevany Paulino de Pinho

    2012-01-01

    Full Text Available Components in complex matrices can cause variations in chromatographic response during analysis of pesticides by gas chromatography. These variations are related to the competition between analytes and matrix components for adsorption sites in the chromatographic system. The capacity of the pesticides chlorpyrifos and deltamethrin to be adsorbed in the injector and chromatographic column was evaluated by constructing three isotherms and changing the column heating rate to 10 and 30 ºC min-1. By using ANCOVA to compare the slope of calibration graphs, results showed that the higher the injector temperature (310 ºC the lower the pesticide adsorption. Also, deltamethrin influenced the adsorption of chlorpyrifos on the column chromatographic.

  16. Optimization of RF Compressor in the SPARX Injector

    CERN Document Server

    Ronsivalle, Concetta; Ferrario, Massimo; Serafini, Luca; Spataro, Bruno

    2005-01-01

    The SPARX photoinjector consists in a rf gun injecting into three SLAC accelerating sections, the first one operating in the RF compressor configuration in order to achieve higher peak current. A systematic study based on PARMELA simulations has been done in order to optimize the parameters that influence the compression also in view of the application of this system as injector of the so called SPARXINO 3-5 nm FEL test facility. The results of computations show that peak currents at the injector exit up to kA level are achievable with a good control of the transverse and longitudinal emittance by means of a short SW section operating at 11424 MHz placed before the first accelerating section. Some working points in different compression regimes suitable for FEL experiments have been selected. The stability of these points and the sensitivity to various types of random errors are discussed.

  17. Real Time Monitoring of Diesel Engine Injector Waveforms for Accurate Fuel Metering and Control

    Directory of Open Access Journals (Sweden)

    Q. R. Farooqi

    2013-01-01

    Full Text Available This paper presents the development, experimentation, and validation of a reliable and robust system to monitor the injector pulse generated by an engine control module (ECM which can easily be calibrated for different engine platforms and then feedback the corresponding fueling quantity to the real-time computer in a closed-loop controller in the loop (CIL bench in order to achieve optimal fueling. This research utilizes field programmable gate arrays (FPGA and direct memory access (DMA transfer capability to achieve high speed data acquisition and delivery. This work is conducted in two stages: the first stage is to study the variability involved in the injected fueling quantity from pulse to pulse, from injector to injector, between real injector stators and inductor load cells, and over different operating conditions. Different thresholds have been used to find out the best start of injection (SOI threshold and the end of injection (EOI threshold that capture the injector “on-time” with best reliability and accuracy. Second stage involves development of a system that interprets the injector pulse into fueling quantity. The system can easily be calibrated for various platforms. Finally, the use of resulting correction table has been observed to capture the fueling quantity with highest accuracy.

  18. Use of the Keele injector for sample introduction for gas chromatographic analysis of vinclozolin in lettuces.

    Science.gov (United States)

    Shim, J H; Lee, Y S; Kim, M R; Lee, C J; Kim, I S

    2003-10-10

    We examined a Keele injector for sample introduction for gas chromatographic analysis of vinclozolin treated in lettuces. Samples in milligram quantity were introduced into a glass tube in a Keele injector at a gas chromatograph injection port. The glass tube was then crushed to allow the sample to carry onto a capillary column in a normal manner. The standard calibration curve for quantitative detection of vinclozolin was obtained by determining vinclozolin spiked in samples at variable concentrations. The calibration curve showed a linear response to vinclozolin ranging from 0.05 to 1.0 microg/g, giving a slope value of 174.8, the y-intercept value of -2.8146 and the mean r2-value of 0.9994. Limit of quantification for vinclozolin was 0.05 microg/g by this method, comparable to 0.01 microg/g by a normal injector. When samples treated previously with vinclozolin were determined by the Keele injector, vinclozolin was found to be about 30% lower as compared to a normal method, suggesting about 70% recovery of the spiked vinclozolin by the Keele injector. From these results, the Keele injector was suggested to be potential for sample introduction in gas chromatographic analysis of vinclozolin in lettuce samples.

  19. The CH section of the 17 MeV injector for MYRRHA

    International Nuclear Information System (INIS)

    Maeder, Dominik

    2015-01-01

    The newly developed beam-dynamics design for the MYRRHA injector was optimized in view of a high reliability and availability and fulfills all requirements of the nuclear reactor. The basic concept of the EUROTRANS injector was revised and further developed. Ar result of this work among others the quality of the excite beam could be distrinctly improved. In the statistical error analysis the beam dynamics have been shown as extremely robust and yields even under most pessimistic error assumptions a transmission of above 99.9 %. The new injector concept offers essential advances against the injector design presented in ''MAX Referenzdesign 012'' and is applied as new ''MAX Referenzdesign 2014''. The development history until the new reference design was a successive process with numerous iterative intermediate steps. With the altrnative design (C1) and the consolidated alternative design (C2) in this thesis also the milestones of the injector development are described. The good beam-dynamical properties of the new injector design (C3) could be confirmed in comparison calculations with TraceWin at the IN2P3 rate at CNRS. Beside the beam dynamics the required accelerator cavities were developed and optimized for a high reliability and availability too. The RF design of the CH structures is layed out for a most possible breakdown safety in the operation with low electrical field gradients far below the technical power limits and possibilities of each cavity.

  20. Intelligent Automated Nuclear Fuel Pellet Inspection System

    International Nuclear Information System (INIS)

    Keyvan, S.

    1999-01-01

    At the present time, nuclear pellet inspection is performed manually using naked eyes for judgment and decisionmaking on accepting or rejecting pellets. This current practice of pellet inspection is tedious and subject to inconsistencies and error. Furthermore, unnecessary re-fabrication of pellets is costly and the presence of low quality pellets in a fuel assembly is unacceptable. To improve the quality control in nuclear fuel fabrication plants, an automated pellet inspection system based on advanced techniques is needed. Such a system addresses the following concerns of the current manual inspection method: (1) the reliability of inspection due to typical human errors, (2) radiation exposure to the workers, and (3) speed of inspection and its economical impact. The goal of this research is to develop an automated nuclear fuel pellet inspection system which is based on pellet video (photographic) images and uses artificial intelligence techniques

  1. Design of in situ dispersible and calcium cross-linked alginate pellets as intestinal-specific drug carrier by melt pelletization technique.

    Science.gov (United States)

    Nurulaini, Harjoh; Wong, Tin Wui

    2011-06-01

    Conventional alginate pellets underwent rapid drug dissolution and loss of multiparticulate characteristics such as aggregation in acidic medium, thereby promoting oral dose dumping. This study aimed to design sustained-release dispersible alginate pellets through rapid in situ matrix dispersion and cross-linking by calcium salts during dissolution. Pellets made of alginate and calcium salts were prepared using a solvent-free melt pelletization technique that prevented reaction between processing materials during agglomeration and allowed such a reaction to occur only in dissolution phase. Drug release was remarkably retarded in acidic medium when pellets were formulated with water-soluble calcium acetate instead of acid-soluble calcium carbonate. Different from calcium salt-free and calcium carbonate-loaded matrices that aggregated or underwent gradual erosion, rapid in situ solvation of calcium acetate in pellets during dissolution resulted in burst of gas bubbles, fast pellet breakup, and dispersion. The dispersed fragments, though exhibiting a larger specific surface area for drug dissolution than intact matrix, were rapidly cross-linked by Ca(2+) from calcium acetate and had drug release retarded till a change in medium pH from 1.2 to 6.8. Being dispersible and pH-dependent in drug dissolution, these pellets are useful as multiparticulate intestinal-specific drug carrier without exhibiting dose dumping tendency of a "single-unit-like" system via pellet aggregation. Copyright © 2011 Wiley-Liss, Inc.

  2. Co-combustion of anthracite coal and wood pellets: Thermodynamic analysis, combustion efficiency, pollutant emissions and ash slagging.

    Science.gov (United States)

    Guo, Feihong; Zhong, Zhaoping

    2018-08-01

    This work presents studies on the co-combustion of anthracite coal and wood pellets in fluidized bed. Prior to the fluidized bed combustion, thermogravimetric analysis are performed to investigate the thermodynamic behavior of coal and wood pellets. The results show that the thermal decomposition of blends is divided into four stages. The co-firing of coal and wood pellets can promote the combustion reaction and reduce the emission of gaseous pollutants, such as SO 2 and NO. It is important to choose the proportion of wood pellets during co-combustion due to the low combustion efficiency caused by large pellets with poor fluidization. Wood pellets can inhibit the volatilization of trace elements, especially for Cr, Ni and V. In addition, the slagging ratio of wood pellets ash is reduced by co-firing with coal. The research on combustion of coal and wood pellets is of great significance in engineering. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Use of coffee (Coffea arabica pulp for the production of briquettes and pellets for heat generation

    Directory of Open Access Journals (Sweden)

    Robert Cubero-Abarca

    2014-10-01

    Full Text Available Coffee bean (Coffea arabica processing generates high amount of residues that are sources of environmental pollution. Therefore, an appropriate solution is needed. The objective of this study was to determine the potential of coffee pulp to produce briquettes and pellets. The study included pulp drying (using air, solar and hot air methods; the production of briquettes and pellets; the evaluation of their energy, physical and mechanical properties; and the evaluation of pellet quality using X-ray densitometry. The results showed that the pulp presented an initial moisture content of 90%, resulting in drying times of 699, 308 and 55 hours for air, solar and hot air drying, respectively, and the calorific values of the pellets and briquettes were 12,501 kJ kg-1 and 11,591 kJ kg-1, respectively. The ash content was 8.68% for the briquettes and 6.74% for the pellets. The density of the briquettes was 1,110 kg m-3, compared with 1,300 kg m-3 for the pellets. The apparent densities were 1,000 kg m-3 and 600 kg m-3 for the briquettes and pellets, respectively, and the water absorptions by the briquettes were 7.90% and 8.10% by the pellets. The maximum horizontal compression effort was 26.86 kg cm-2, measured in the pellets, compared with 4.52 kg cm-2 in the briquettes. The maximum horizontal load was 93.24 kg, measured in the briquettes, compared with 33.50 kg in the pellets. The value of the pellet durability test was 75.54%. X-ray densitometry showed that the pellet was uniform and a few cracks were observed on the pellet surface.

  4. Lithium pellet production (LiPP): A device for the production of small spheres of lithium

    Science.gov (United States)

    Fiflis, P.; Andrucyzk, D.; Roquemore, A. L.; McGuire, M.; Curreli, D.; Ruzic, D. N.

    2013-06-01

    With lithium as a fusion material gaining popularity, a method for producing lithium pellets relatively quickly has been developed for NSTX. The Lithium Pellet Production device is based on an injector with a sub-millimeter diameter orifice and relies on a jet of liquid lithium breaking apart into small spheres via the Plateau-Rayleigh instability. A prototype device is presented in this paper and for a pressure difference of ΔP = 5 Torr, spheres with diameters between 0.91 < D < 1.37 mm have been produced with an average diameter of D = 1.14 mm, which agrees with the developed theory. Successive tests performed at Princeton Plasma Physics Laboratory with Wood's metal have confirmed the dependence of sphere diameter on pressure difference as predicted.

  5. The SSRL injector beam position monitoring systems

    International Nuclear Information System (INIS)

    Lavender, W.; Baird, S.; Brennan, S.; Borland, M.; Hettel, R.; Nuhn, H.D.; Ortiz, R.; Safranek, J.; Sebek, J.; Wermelskirchen, C.; Yang, J.

    1991-01-01

    The beam position monitoring system of the SSRL injector forms a vital component of its operation. Several different types of instrumentation are used to measure the position or intensity of the electron beam in the injector. These include current toroids, fluorescent screens, Faraday cups, the 'Q' meter, a synchrotron light monitor, and electron beam position monitors. This paper focuses on the use of the electron beam position monitors to measure electron trajectories in the injector transport lines and the booster ring. The design of the beam position monitors is described in another paper to be presented at this conference. There are three different beam position monitor systems in the injector. One system consists of a set of five BPMs located on the injection transport line from the linac to the booster (known as the LTB line). There is a second system of six BPMs located on the ejection transport line (known as the BTS line). Finally, there is an array of 40 BPMs installed on the main booster ring itself. This article describes the software and processing electronics of the systems used to measure electron beam trajectories for the new SSRL injector for SPEAR

  6. Tokamak fuelling with pellets: Effect of transport phenomena on the injection requirements

    International Nuclear Information System (INIS)

    Lengyel, L.L.

    1979-01-01

    Results of calculations on pellet-plasma interaction that take into account transport phenomena inherent in tokamak plasmas are analyzed. It is shown that the results obtained by different authors on the optimum pellet penetration depth and required pellet injection frequencies, which are partly contradictory, can be explained by means of the different transport processes taken into account or neglected in the calculations concerned. (orig.)

  7. Fabrication of Cr-doped UO2 Fuel Pellet using Liquid Phase Sintering

    International Nuclear Information System (INIS)

    Kim, Dong Joo; Yang, Jae Ho; Kim, Keon Sik; Rhee, Young Woo; Kim, Jong Hun; Oh, Jang Soo; Koo, Yang Hyun

    2013-01-01

    An enhancement of the thermal conductivity of a pellet can be obtained by the addition of a higher thermal conductive material in the pellet. In addition, the resistance to the PCI can be increased through a plasticity increase of the pellet. Thermal conductivity of ceramic materials is generally lower than that of metallic materials. The thermal conductivity of uranium oxide which is a typical ceramic material is low as well. The steep temperature gradient in the fuel pellet results from the low thermal conductivity. Therefore, the thermal conductivity improvement of a nuclear fuel pellet can enhance the fuel performance in various aspects. The lower centerline temperature of a fuel pellet affects the enhancement of fuel safety as well as fuel pellet integrity during nuclear reactor operation. Besides, the nuclear reactor power can be uprated due to the higher safety margin. So, many researches to enhance the thermal conductivity of nuclear fuel pellet have been performed in various ways. To improve the thermal conductivity of UO 2 pellet, an appropriate arrangement of the high thermal conductive material in UO 2 matrix is one of the various methods. We intended to control a placement of chromium as the high thermal conductive material. The metallic chromium and chromium oxide were arranged in a grain boundary of UO 2 using a liquid phase sintering method. The liquid phase sintering of Cr-doped UO 2 pellet could be adjusted using a control of an oxygen potential in sintering atmosphere

  8. Pellet fired appliances. Market survey. 7. rev. ed.; Pelletheizungen. Marktuebersicht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-01-15

    The market survey under consideration reports on pellet central heating systems and pellet fired appliances. The main chapters of this market survey are concerned to: (1) Information on wood pellets and pellet fired appliances; (2) Information about the interpretation of the market survey; (3) Survey of all compared pellet fired appliances with respect to the nominal power; (4) Price lists of pellet fired appliances and pellet central heating systems; (5) Type sheets of the compared pellet fired appliances and pellet central heating systems. Finally, this brochure contains the addresses of the produces and distribution partners of pellet fired appliances and pellet central heating systems.

  9. Use of implantable pellets to administer low levels of methyl mercury to fish

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, B.S.; Jagoe, C.H.; Gross, T.S.

    1999-07-01

    Implantable pellets of methyl mercury chloride were tested in Nile Tilapia (oreochromis niloticus) to appraise the effectiveness of the method for chronic studies of mercury. Two dosing regimes of 15 and 1.5 grams/CH{sub 3}HgCl pellet (test 1) and 1 and 0.1 grams/pellet (tests 2--3) of methyl mercury chloride were used in three tests. Additional pellets containing only matrix were used as controls. The pellets were inserted into the peritoneal cavity along with a microchip for identification. Three methods of incision closure: sutures and two types of surgical glue, were tested. Pellets used in test one released the dose too fast, resulting in premature death of the fish. Results from tests 2 and 3 show blood mercury concentrations over time and tissue levels at necropsy consistent with dose suggestion that this is a viable method of dosing fish.

  10. A proposed injector for the LCLS linac

    International Nuclear Information System (INIS)

    Yeremian, A.D.; Bharadwaj, V.K.; Emma, P.; Miller, R.H.; Palmer, D.T.; Woodley, M.D.

    1996-11-01

    The Linac Coherent Light Source (LCLS) will use the last portion of the SLAC accelerator as a driver for a short wavelength FEL. The injector must produce 1-nC, 3-ps rms electron bunches at a repetition rate of up to 120 Hz with a normalized rms emittance of about 1 mm-mrad. The injector design takes advantage of the photocathode rf gun technology developed since its conception in the mid 1980's, in particular the S-band rf gun developed by the SLAC/BNL/UCLA collaboration, and emittance compensation techniques developed in the last decade. The injector beamline has been designed using the SUPERFISH, POISSON, PARMELA, and TRANSPORT codes in a consistent way to simulate the beam from the gun up to the entrance of the main accelerator linac where the beam energy is 150 MeV. PARMELA simulations indicate that at 150 MeV, space charge effects are negligible

  11. LTP fibre injector qualification and status

    International Nuclear Information System (INIS)

    Bogenstahl, J; Cunningham, L; Fitzsimons, E D; Hough, J; Killow, C J; Perreur-Lloyd, M; Robertson, D; Rowan, S; Ward, H

    2009-01-01

    This paper presents the current state of the LISA Technology Package (LTP) fibre injector qualification project in terms of vibration and shock tests. The fibre injector is a custom built part and therefore must undergo a full space qualification process. The mounting structure and method for sinusoidal vibration and random vibration tests as well as shock tests will be presented. Furthermore a proposal will be presented to use the fibre injector pair qualification model to build an optical prototype bench. The optical prototype bench is a full-scale model of the flight model. It will be used for development and rehearsal of all the assembly stages of the flight model and will provide an on-ground simulator for investigation as an updated engineering model.

  12. Status of the SPIRAL2 injector commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Thuillier, T., E-mail: thuillier@lpsc.in2p3.fr; Angot, J.; Jacob, J.; Lamy, T.; Sole, P. [LPSC, Université Grenoble Alpes, CNRS/IN2P3, 53 rue des Martyrs, 38026 Grenoble Cedex (France); Barué, C.; Bertrand, P.; Canet, C.; Ferdinand, R.; Flambard, J.-L.; Jardin, P.; Lemagnen, F.; Maunoury, L.; Osmond, B. [GANIL, CNRS/IN2P3, Bvd Henri Becquerel, BP 55027, 14076 Caen Cedex 5 (France); Biarrotte, J. L. [IPN Orsay, Université Paris Sud, CNRS/IN2P3, 15 rue Georges Clémenceau, 91406 Orsay Cedex (France); Denis, J.-F.; Roger, A.; Touzery, R.; Tuske, O.; Uriot, D. [Irfu, CEA Saclay, DSM/Irfu/SACM, 91191 Gif Sur Yvette (France); and others

    2016-02-15

    The SPIRAL2 injector, installed in its tunnel, is currently under commissioning at GANIL, Caen, France. The injector is composed of two low energy beam transport lines: one is dedicated to the light ion beam production, the other to the heavy ions. The first light ion beam, created by a 2.45 GHz electron cyclotron resonance ion source, has been successfully produced in December 2014. The first beam of the PHOENIX V2 18 GHz heavy ion source was analyzed on 10 July 2015. A status of the SPIRAL2 injector commissioning is given. An upgrade of the heavy ion source, named PHOENIX V3 aimed to replace the V2, is presented. The new version features a doubled plasma chamber volume and the high charge state beam intensity is expected to increase by a factor of 1.5 to 2 up to the mass ∼50. A status of its assembly is proposed.

  13. Neutral beam injector performance on the PLT and PDX tokamaks

    International Nuclear Information System (INIS)

    Schilling, G.; Ashcroft, D.L.; Eubank, H.P.; Grisham, L.R.; Kozub, T.A.; Kugel, H.W.; Rossmassler, J.; Williams, M.D.

    1981-02-01

    An overall injector system description is presented first, and this will be followed by a detailed discussion of those problems unique to multiple injector operation on the tokamaks, i.e., power transmission, conditioning, reliability, and failures

  14. Spray Modeling for Outwardly-Opening Hollow-Cone Injector

    KAUST Repository

    Sim, Jaeheon; Badra, Jihad; Elwardani, Ahmed Elsaid; Im, Hong G.

    2016-01-01

    linear instability sheet atomization (LISA) model was originally developed for pressure swirl hollow-cone injectors with moderate spray angle and toroidal ligament breakups. Therefore, it is not appropriate for the outwardly-opening injectors having wide

  15. RF Photoelectric injectors using needle cathodes

    International Nuclear Information System (INIS)

    Lewellen, J.W.; Brau, C.A.

    2003-01-01

    Photocathode RF guns, in various configurations, are the injectors of choice for both current and future applications requiring high-brightness electron beams. Many of these applications, such as single-pass free-electron lasers, require beams with high brilliance but not necessarily high charge per bunch. Field-enhanced photoelectric emission has demonstrated electron-beam current density as high as 10 10 A/m 2 , with a quantum efficiency in the UV that approaches 10% at fields on the order of 10 10 V/m. Thus, the use of even a blunt needle holds promise for increasing cathode quantum efficiency without sacrificing robustness. We present an initial study on the use of needle cathodes in photoinjectors to enhance beam brightness while reducing beam charge. Benefits include lower drive-laser power requirements, easier multibunch operation, lower emittance, and lower beam degradation due to charge-dependent effects in the postinjector accelerator. These benefits result from a combination of a smaller cathode emission area, greatly enhanced RF field strength at the cathode, and the charge scaling of detrimental postinjector linac effects, e.g., transverse wakefields and CSR

  16. RF Photoelectric injectors using needle cathodes

    Science.gov (United States)

    Lewellen, J. W.; Brau, C. A.

    2003-07-01

    Photocathode RF guns, in various configurations, are the injectors of choice for both current and future applications requiring high-brightness electron beams. Many of these applications, such as single-pass free-electron lasers, require beams with high brilliance but not necessarily high charge per bunch. Field-enhanced photoelectric emission has demonstrated electron-beam current density as high as 10 10 A/m 2, with a quantum efficiency in the UV that approaches 10% at fields on the order of 10 10 V/m. Thus, the use of even a blunt needle holds promise for increasing cathode quantum efficiency without sacrificing robustness. We present an initial study on the use of needle cathodes in photoinjectors to enhance beam brightness while reducing beam charge. Benefits include lower drive-laser power requirements, easier multibunch operation, lower emittance, and lower beam degradation due to charge-dependent effects in the postinjector accelerator. These benefits result from a combination of a smaller cathode emission area, greatly enhanced RF field strength at the cathode, and the charge scaling of detrimental postinjector linac effects, e.g., transverse wakefields and CSR.

  17. Recent progress in photo-injectors

    International Nuclear Information System (INIS)

    Ben-Zvi, I.

    1996-10-01

    In photoinjector electron guns, electrons are emitted from a photocathode by a short laser pulse and then accelerated by intense RF fields in a resonant cavity. Photoinjectors are very versatile tools. Normally we think of them in terms of the production of high electron density in 6-D phase space, for reasons such as injection to laser accelerators, generation of x-rays by Compton scattering and short wavelength FELs. Another example for the use of photo-injectors is the production of a high charge in a short time, for wake- field acceleration, two-beam accelerators and high-power, long-wavelength FELs. There are other potential uses, such as the generation of polarized electrons, compact accelerators for industrial applications and more. Photoinjectors are in operation in many electron accelerator facilities and a large number of new guns are under construction. The purpose of this work is to present some trend setting recent results that have been obtained in some of these laboratories. In particular the subjects of high density in 6-D phase space, new diagnostic tools, photocathode advances and high-charge production will be discussed

  18. Micro-injector for capillary electrophoresis.

    Science.gov (United States)

    Sáiz, Jorge; Koenka, Israel Joel; García-Ruiz, Carmen; Müller, Beat; Chwalek, Thomas; Hauser, Peter C

    2015-08-01

    A novel micro-injector for capillary electrophoresis for the handling of samples with volumes down to as little as 300 nL was designed and built in our laboratory for analyses in which the available volume is a limitation. The sample is placed into a small cavity located directly in front of the separation capillary, and the injection is then carried out automatically by controlled pressurization of the chamber with compressed air. The system also allows automated flushing of the injection chamber as well as of the capillary. In a trial with a capillary electrophoresis system with contactless conductivity detector, employing a capillary of 25 μm diameter, the results showed good stability of migration times and peak areas. To illustrate the technique, the fast separation of five inorganic cations (Na(+) , K(+) , NH4 (+) , Ca(2+) , and Mg(2+) ) was set up. This could be achieved in less than 3 min, with good limits of detection (10 μM) and linear ranges (between about 10 and 1000 μM). The system was demonstrated for the determination of the inorganic cations in porewater samples of a lake sediment core. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Nuclear fuel pellet production method and nuclear fuel pellet

    International Nuclear Information System (INIS)

    Yuda, Ryoichi; Ito, Ken-ichi; Masuda, Hiroshi.

    1993-01-01

    In a method of manufacturing nuclear fuel pellets by compression-molding UO 2 powders followed by sintering, a sintering agent having a composition of about 40 to 80 wt% of SiO 2 and the balance of Al 2 O 3 , a sintering agent at a ratio of 10 to 500 ppm based on the total amount of UO 2 and UO 2 powders are mixed, compression molded and then sintered at a sintering temperature of about 1500 of 1800degC. The UO 2 particles have an average grain size of about 20 to 60μm, most of the crystal grain boundary thereof is coated with a glassy or crystalline alumina silicate phase, and the porosity is about 1 to 4 vol%. With such a constitution, the sintering agent forms a single liquid phase eutectic mixture during sintering, to promote a surface reaction between nuclear fuel powders by a liquid phase sintering mechanism, increase their density and promote the crystal growth. Accordingly, it is possible to lower the softening temperature, improve the creep velocity of the pellets and improve the resistance against pellet-clad interaction. (T.M.)

  20. Wood pellets and work environment; Traepiller og arbejdsmiljoe

    Energy Technology Data Exchange (ETDEWEB)

    Skov, S.

    2012-07-01

    The project aim was to evaluate the working environment in the production, transport and use of wood pellets. Furthermore, obtained knowledge and guidelines should be disseminated to relevant audiences. The first aim was achieved by making dust measurements at various relevant locations and analyze the results. Several technical problems regarding the measurements occurred during the project. In general, the manual handling of pellets often is a short-term task, which limits the amount of dust that can be collected on the sampling filter. The solution to this problem could be the use of in situ monitoring equipment, however, this technic did not work well for wood dust. Dissemination is mainly done by publishing the findings and guidelines on the webpage www.fyrmedpiller.dk. The result shows that there are widespread dust problems associated with the use and handling of pellets. The result may have been expected in the wood pellet industry, which has been reluctant to support this project. Legislation on the working environment has set a threshold limit for the dust concentration in the air on max 1 mg of dust per cubic meters of air over a working day and in over shorter periods this limit may be doubled. These threshold values were exceeded in many cases. Brief overview: The production of pellets takes place in a very dusty working environment, but the specific pelletizing and bagging processes only produce limited amounts of dust. The dust problems are major in the large warehouses where the handling of the raw material for the pellets increases the dust concentration in the air to levels that by far exceeds the legal threshold values. The work is mainly carried out from the cabin of different machines e.g. loaders and bobcats. It turns out that the average dust concentration in these cabins with filters also exceeds the threshold values. The transports of wood pellets include loading, unloading and delivery of loose pellets, all situations that are critical

  1. Power from Pellets Technology and Applications

    CERN Document Server

    Döring, Stefan

    2013-01-01

    This book provides a practical description of the technology of pellet production on the basis of renewable sources as well as the utilization of pellets. The author explains what kinds of biomass are usable in addition to wood, how to produce pellets and how to use pellets to produce energy. Starting with the basics of combustion, gasification and the pelletizing process, several different technologies are described. The design, planning, construction and economic efficiency are discussed as well. The appendix gives useful advice about plant concepts, calculations, addresses, conversion tables and formulas.

  2. Beam divergence scaling in neutral beam injectors

    International Nuclear Information System (INIS)

    Holmes, A.J.T.

    1976-01-01

    One of the main considerations in the design of neutral beam injectors is to monimize the divergence of the primary ion beam and hence maximize the beam transport and minimize the input of thermal gas. Experimental measurements of the divergence of a cylindrical ion beam are presented and these measurements are used to analyze the major components of ion beam divergence, namely: space charge expansion, gas-ion scattering, emittance and optical aberrations. The implication of these divergence components in the design of a neutral beam injector system is discussed and a method of maximizing the beam current is described for a given area of source plasma

  3. The Fermilab Main Injector Technical Design Handbook

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1994-08-01

    This report contains a description of the design, cost estimate, and construction schedule of the Fermilab Main Injector (FMI) Project. The technical, cost, and schedule baselines for the FMI Project have already been established and may be found in the Fermilab Main Injector Title I Design Report, issued in August 1992. This report updates and expands upon the design and schedule for construction of all subsystem components and associated civil construction described in the Title I Design Report. The facilities described have been designed in conformance with DOE 6430.1A, "United States Department of Energy General Design Criteria."

  4. Mechanical design for TMX injector system

    International Nuclear Information System (INIS)

    Calderon, M.O.; Chen, F.F.K.; Denhoy, B.S.

    1977-01-01

    The injector system for the Tandem Mirror Experiment (TMX) contains the components required to create and maintain a high-temperature, high-density plasma. These components include a streaming-plasma gun in each of the plug tanks to form the target-plasma, 24 neutral-beam source modules for injecting neutral deuterium atoms to heat and replace losses from the plasma, and a gas box system that applies a streaming cold gas to the plasma to stabilize it. This paper discusses the mechanical design problems and solutions for this injector system

  5. Narrow electron injector for ballistic electron spectroscopy

    International Nuclear Information System (INIS)

    Kast, M.; Pacher, C.; Strasser, G.; Gornik, E.

    2001-01-01

    A three-terminal hot electron transistor is used to measure the normal energy distribution of ballistic electrons generated by an electron injector utilizing an improved injector design. A triple barrier resonant tunneling diode with a rectangular transmission function acts as a narrow (1 meV) energy filter. An asymmetric energy distribution with its maximum on the high-energy side with a full width at half maximum of ΔE inj =10 meV is derived. [copyright] 2001 American Institute of Physics

  6. 3D MHD simulations of pellet injection and disruptions in tokamak plasmas

    International Nuclear Information System (INIS)

    Strauss, H.R.; Park, W.; Belova, E.; Fu, G.Y.; Sugiyama, L.E.

    2001-01-01

    Nonlinear MHD simulation results of pellet injection show that MHD forces can accelerate large pellets, injected on the high field side of a tokamak, to the plasma center. Magnetic reconnection can produce a reverse shear q profile. Ballooning instability caused by pellets is also reduced by high field side injection. Studies are also reported of the current quench phase of disruptions, which can cause 3D halo currents and runaway electrons. (author)

  7. 3D MHD simulations of pellet injection and disruptions in tokamak plasmas

    International Nuclear Information System (INIS)

    Strauss, H.R.; Park, W.; Belova, E.; Fu, G.Y.; Sugiyama, L.E.

    1999-01-01

    Nonlinear MHD simulation results of pellet injection show that MHD forces can accelerate large pellets, injected on the high field side of a tokamak, to the plasma center. Magnetic reconnection can produce a reverse shear q profile. Ballooning instability caused by pellets is also reduced by high field side injection. Studies are also reported of the current quench phase of disruptions, which can cause 3D halo currents and runaway electrons. (author)

  8. Impact of fuel quality and burner capacity on the performance of wood pellet stove

    OpenAIRE

    Petrović-Bećirović Sanja B.; Manić Nebojša G.; Stojiljković Dragoslava D.

    2015-01-01

    Pellet stoves may play an important role in Serbia in the future when fossil fuel fired conventional heating appliances are replaced by more efficient and environmentally friendly devices. Experimental investigation was conducted in order to examine the influence of wood pellet quality, as well as burner capacity (6, 8 and 10 kW), used in the same stove configuration, on the performance of pellet stove with declared nameplate capacity of 8 kW. The results o...

  9. Wood pellets : a worldwide fuel commodity

    International Nuclear Information System (INIS)

    Melin, S.

    2005-01-01

    Aspects of the wood pellet industry were discussed in this PowerPoint presentation. Details of wood pellets specifications were presented, and the wood pellet manufacturing process was outlined. An overview of research and development activities for wood pellets was presented, and issues concerning quality control were discussed. A chart of the effective calorific value of various fuels was provided. Data for wood pellet mill production in Canada, the United States and the European Union were provided, and various markets for Canadian wood pellets were evaluated. Residential sales as well as Canadian overseas exports were reviewed. Production revenues for British Columbia and Alberta were provided. Wood pellet heat and electricity production were discussed with reference to prefabricated boilers, stoves and fireplaces. Consumption rates, greenhouse gas (GHG) emissions, and fuel ratios for wood pellets and fossil fuels were compared. Price regulating policies for electricity and fossil fuels have prevented the domestic expansion of the wood pellet industry. There are currently no incentives for advanced biomass combustion to enter British Columbia markets, and this has led to the export of wood pellets. It was concluded that climate change mitigation policies will be a driving force behind market expansion for wood pellets. tabs., figs

  10. Wood pellet milling tests in a suspension-fired power plant

    DEFF Research Database (Denmark)

    Masche, Marvin; Puig-Arnavat, Maria; Wadenbäck, Johan

    2018-01-01

    classification (i.e., the classifier cut size) are affected by the internal pellet particle size distribution obtained after pellet disintegration in hot water. Furthermore, optimal conditions for comminuting pellets were identified. The milling behavior was assessed by determining the specific grinding energy...... consumption and the differential mill pressure. The size and shape of comminuted pellets sampled from burner pipes were analyzed by dynamic image analysis and sieve analysis, respectively. The results showed that the internal pellet particle size distribution affected both the milling behavior...... similar. Mill operating changes had a negligible effect on the original elongated wood particle shape. To achieve the desired comminuted product fineness (i.e., the classifier cut size) with lower specific grinding energy consumption, power plant operators need to choose pellets with a finer internal...

  11. Carbothermal Reduction of Iron Ore in Its Concentrate-Agricultural Waste Pellets

    Directory of Open Access Journals (Sweden)

    Zhulin Liu

    2018-01-01

    Full Text Available Carbon-containing pellets were prepared with the carbonized product of agricultural wastes and iron concentrate, and an experimental study on the direct reduction was carried out. The experimental results demonstrated that carbon-containing pellets could be rapidly reduced at 1200 to 1300°C in 15 minutes, and the proper holding time at high temperature was 15 to 20 min. The degree of reduction gradually increased with temperature rising, and the appropriate temperature of reducing pellets was 1200°C. The weight loss rate and reduction degree of pellets increased with the rise of carbon proportion, and the relatively reasonable mole ratio of carbon to oxygen was 0.9. A higher content of carbon and an appropriate content of volatile matters in biomass char were beneficial to the reduction of pellets. The carbon-containing pellets could be reduced at high speeds in the air, but there was some reoxidization phenomenon.

  12. 21 CFR 870.1670 - Syringe actuator for an injector.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Syringe actuator for an injector. 870.1670 Section 870.1670 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... actuator for an injector. (a) Identification. A syringe actuator for an injector is an electrical device...

  13. Pellet injection into H-mode ITER plasma with the presence of internal transport barriers

    Science.gov (United States)

    Leekhaphan, P.; Onjun, T.

    2011-04-01

    The impacts of pellet injection into ITER type-1 ELMy H-mode plasma with the presence of internal transport barriers (ITBs) are investigated using self-consistent core-edge simulations of 1.5D BALDUR integrated predictive modeling code. In these simulations, the plasma core transport is predicted using a combination of a semi-empirical Mixed B/gB anomalous transport model, which can self-consistently predict the formation of ITBs, and the NCLASS neoclassical model. For simplicity, it is assumed that toroidal velocity for ω E× B calculation is proportional to local ion temperature. In addition, the boundary conditions are predicted using the pedestal temperature model based on magnetic and flow shear stabilization width scaling; while the density of each plasma species, including both hydrogenic and impurity species, at the boundary are assumed to be a large fraction of its line averaged density. For the pellet's behaviors in the hot plasma, the Neutral Gas Shielding (NGS) model by Milora-Foster is used. It was found that the injection of pellet could result in further improvement of fusion performance from that of the formation of ITB. However, the impact of pellet injection is quite complicated. It is also found that the pellets cannot penetrate into a deep core of the plasma. The injection of the pellet results in a formation of density peak in the region close to the plasma edge. The injection of pellet can result in an improved nuclear fusion performance depending on the properties of pellet (i.e., increase up to 5% with a speed of 1 km/s and radius of 2 mm). A sensitivity analysis is carried out to determine the impact of pellet parameters, which are: the pellet radius, the pellet velocity, and the frequency of injection. The increase in the pellet radius and frequency were found to greatly improve the performance and effectiveness of fuelling. However, changing the velocity is observed to exert small impact.

  14. Hot-melt extrusion of sugar-starch-pellets.

    Science.gov (United States)

    Yeung, Chi-Wah; Rein, Hubert

    2015-09-30

    Sugar-starch-pellets (syn. sugar spheres) are usually manufactured through fluidized bed granulation or wet extrusion techniques. This paper introduces hot-melt extrusion (HME) as an alternative method to manufacture sugar-starch-pellets. A twin-screw extruder coupled with a Leistritz Micro Pelletizer (LMP) cutting machine was utilized for the extrusion of different types (normal-, waxy-, and high-amlyose) of corn starch, blended with varying amounts of sucrose. Pellets were characterized for their physicochemical properties including crystallinity, particle size distribution, tensile strength, and swelling expansion. Furthermore, the influence of sugar content and humidity on the product was investigated. Both sucrose and water lowered the Tg of the starch system allowing a convenient extrusion process. Mechanical strength and swelling behavior could be associated with varying amylose and amylopectin. X-ray powder diffractometric (XRPD) peaks of increasing sucrose contents appeared above 30%. This signified the oversaturation of the extruded starch matrix system with sucrose. Otherwise, had the dissolved sucrose been embedded into the molten starch matrix, no crystalline peak could have been recognized. The replacement of starch with sucrose reduced the starch pellets' swelling effect, which resulted in less sectional expansion (SEI) and changed the surface appearance. Further, a nearly equal tensile strength could be detected for sugar spheres with more than 40% sucrose. This observation stands in good relation with the analyzed values of the commercial pellets. Both techniques (fluidized bed and HME) allowed a high yield of spherical pellets (less friability) for further layering processes. Thermal influence on the sugar-starch system is still an obstacle to be controlled. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Model for pneumatic pellet injection

    International Nuclear Information System (INIS)

    Hogan, J.T.; Milora, S.L.; Schuresko, D.D.

    1983-07-01

    A hydrodynamic code has been developed to model the performance of pneumatic pellet injection systems. The code describes one dimensional, unsteady compressible gas dynamics, including gas friction and heat transfer to the walls in a system with variable area. The mass, momentum, and energy equations are solved with an iterated Lax-Wendroff scheme with additional numerical viscosity. The code is described and comparisons with experimental data are presented

  16. Impacts of pellets injected from the low-field side on plasma in ITER

    International Nuclear Information System (INIS)

    Wisitsorasak, A.; Onjun, T.

    2011-01-01

    Impacts of pellets injected from the low-field side (LFS) on plasma in ITER are investigated using the 1.5D BALDUR integrated predictive modeling code. In these simulations, the pellet ablation is described using the neutral gas shielding (NGS) model. The pellet ablation model is coupled with the plasma core transport model, which is a combination of the MMM95 anomalous transport model and NCLASS neoclassical transport model. The boundary conditions are assumed to be at the top of the pedestal, in which the pedestal parameters are predicted using a pedestal model based on the theoretical-based pedestal width scaling (either magnetic and flow shear stabilization width scaling, or flow shear stabilization width scaling, or normalized poloidal pressure width scaling) and the infinite-n ballooning mode pressure gradient limit. These pedestal models depend sensitively on the density at the top of the pedestal, which can be strongly influenced by the injection of pellets. The combination of the MMM95 and NCLASS models, together with the pedestal and NGS models, is used to simulate the time evolution of the plasma current, ion and electron temperatures, and density profiles for ITER standard type-I ELMy H-mode discharges during the injection of LFS pellets. It is found that the injection of pellets results in a complicated plasma scenario, especially in the outer region of the plasma and the plasma conditions at the boundary in which the pellet has an impact on increasing the plasma edge density, but reducing the plasma edge temperature. The LFS pellet has a stronger impact on the edge as compared to the center. For fusion performance, the pellet can result in either enhancement or degradation, depending sensitively on the pellet parameters; such as the pellet size, pellet velocity, and pellet frequency. For example, when a series of deuterium pellets with a size of 0.5 cm, velocity of 1 km/s, and frequency of 2 Hz are injected into the ITER plasma from the LFS, the

  17. Determination of the effective source of particles associated with pellet injection. Application to ITER

    International Nuclear Information System (INIS)

    Nehme, H.

    2009-11-01

    The determination of the effective source of particle associated with the injection of a pellet requires a thorough description of both pellet ablation and deposited material homogenization. The goal of this report is the description of such a study. In the first part, which is devoted to ablation physics, we first analyze the relative importance of the different processes shielding the pellet against the plasma heat flux, then present an attempt for validating the calculation of the over-ablation due to the suprathermal ion tail generated by the discharge heating systems and then estimate the influence of the initial shape of the pellet on the ablation rate. In the second part, which is devoted to the description of the drift of the pellet deposited material down the magnetic field gradient, we present a critical review of the drift models available up to now, then compare the measured characteristics of deposition profiles to our own simulations, showing a good agreement. This was done for data originating from different machines. Then, we describe the several improvements brought to our model and demonstrate - which is new, that there is a correlation between the location of the maximum of matter deposition and that of integer (and/or half-integer) q-surfaces. It must be noted that the underlying process is intrinsic to our modeling and that our calculations reproduce reasonably well the observed correlation for both the LFS (Low Field Side) and HFS (High Field Side) pellet data bases of Tore Supra and DIII-D. The last part reports on the modeling of pellet injection in ITER. First, from the present design of the pellet injection system, we estimate the expected deposition depth of the pellet material (ρ/a ∼ 0.85) and the flux to be injected for pacing the ELMs (Edge Localized Mode) and maintaining the core density (between 150 and 200 Pam 3 s -1 ). Then, we present a parametric study demonstrating that it is not possible to improve significantly the fuelling

  18. A study on nozzle flow and spray characteristics of piezo injector for next generation high response injection

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jin Wook [Korea Institue of Machinery and Materials, Daejeon (Korea, Republic of); Min, Kyoung Doug [Seoul National University, Seoul (Korea, Republic of)

    2006-06-15

    Most diesel injector, which is currently used in high-pressure common rail fuel injection system of diesel engine, is driven by the solenoid coil energy for its needle movement. The main disadvantage of this solenoid-driven injector is a high power consumption, high power loss through solenoid coil and relatively fixed needle response's problem. In this study, a prototype piezo-driven injector, as a new injector mechanism driven by piezoelectric energy based on the concept of inverse piezo-electric effect, has been designed and fabricated to know the effect of piezo-driven injection processes on the diesel spray structure and internal nozzle flow. Firstly we investigated the spray characteristics in a constant volume chamber pressurized by nitrogen gas using the back diffusion light illumination method for high-speed temporal photography and also analyzed the inside nozzle flow by a fully transient simulation with cavitation model using VOF(Volume Of Fraction) method. The numerical calculation has been performed to simulate the cavitating flow of 3-dimensional real size single hole nozzle along the injection duration. Results were compared between a conventional solenoid-driven injector and piezo-driven injector, both equipped with the same micro-sac multi-hole injection nozzle. The experimental results show that the piezo-driven injector has short injection delay and a faster spray development and produces higher injection velocity than the solenoid-driven injector. And the predicted simulation results with the degree of cavitation's generation inside nozzle for faster needle response in a piezo-driven injector were reflected to spray development in agreement with the experimental spray images.

  19. A study on nozzle flow and spray characteristics of piezo injector for next generation high response injection

    International Nuclear Information System (INIS)

    Lee, Jin Wook; Min, Kyoung Doug

    2006-01-01

    Most diesel injector, which is currently used in high-pressure common rail fuel injection system of diesel engine, is driven by the solenoid coil energy for its needle movement. The main disadvantage of this solenoid-driven injector is a high power consumption, high power loss through solenoid coil and relatively fixed needle response's problem. In this study, a prototype piezo-driven injector, as a new injector mechanism driven by piezoelectric energy based on the concept of inverse piezo-electric effect, has been designed and fabricated to know the effect of piezo-driven injection processes on the diesel spray structure and internal nozzle flow. Firstly we investigated the spray characteristics in a constant volume chamber pressurized by nitrogen gas using the back diffusion light illumination method for high-speed temporal photography and also analyzed the inside nozzle flow by a fully transient simulation with cavitation model using VOF(Volume Of Fraction) method. The numerical calculation has been performed to simulate the cavitating flow of 3-dimensional real size single hole nozzle along the injection duration. Results were compared between a conventional solenoid-driven injector and piezo-driven injector, both equipped with the same micro-sac multi-hole injection nozzle. The experimental results show that the piezo-driven injector has short injection delay and a faster spray development and produces higher injection velocity than the solenoid-driven injector. And the predicted simulation results with the degree of cavitation's generation inside nozzle for faster needle response in a piezo-driven injector were reflected to spray development in agreement with the experimental spray images

  20. Applications and interactions of solid impurity pellets with reactor relevant plasma

    International Nuclear Information System (INIS)

    Deng Baiquan; Peng Lilin; Huang Jinhua; Yan Jiancheng

    2003-01-01

    Based on the kinetic two-dimensional lentil-shape ablation theory of hydrogenic pellet developed by Kuteev, the new extended algorithm for erosion speed and ablation rate calculations of the impurity pellets in reactor relevant plasma has been derived. The preliminary exploration for the feasibility of applying impurity pellet injection to the α particle diagnostics in the future ITER device has been performed. The comparisons between the numerical integral calculation results and analysis show that the lithium pellet injection possesses much more compatibilities. It might be feasible to apply this technique to both α particle diagnostics and safety factor q profile measurement in the future ITER device. (authors)

  1. Shock and vibration tests of uranium mononitride fuel pellets for a space power nuclear reactor

    Science.gov (United States)

    Adams, D. W.

    1972-01-01

    Shock and vibration tests were conducted on cylindrically shaped, depleted, uranium mononitride (UN) fuel pellets. The structural capabilities of the pellets were determined under exposure to shock and vibration loading which a nuclear reactor may encounter during launching into space. Various combinations of diametral and axial clearances between the pellets and their enclosing structures were tested. The results of these tests indicate that for present fabrication of UN pellets, a diametral clearance of 0.254 millimeter and an axial clearance of 0.025 millimeter are tolerable when subjected to launch-induced loads.

  2. A survey on fuel pellet cracking and healing phenomena in reactor operation

    International Nuclear Information System (INIS)

    Faya, S.C.S.

    1981-10-01

    In normal reactor operation, oxide fuel pellets will crack. The majority of the pellet segments will lie against the cladding. When temperature in the central region of the fuel during irradiation is raised to the plastic region, crack healing occurs. The repetition of cracking-healing-cracking sequence resulting from repeated power cycle has a significant effect on fuel relocation. The fuel pellet relocation must be known since it effects the cladding life time. The fuel pellet cracking and healing phenomeno in reactor operation are described and the pertinant method of analysis is also discussed. (Author) [pt

  3. Evaluation of friction heating in cavitating high pressure Diesel injector nozzles

    Science.gov (United States)

    Salemi, R.; Koukouvinis, P.; Strotos, G.; McDavid, R.; Wang, Lifeng; Li, Jason; Marengo, M.; Gavaises, M.

    2015-12-01

    Variation of fuel properties occurring during extreme fuel pressurisation in Diesel fuel injectors relative to those under atmospheric pressure and room temperature conditions may affect significantly fuel delivery, fuel injection temperature, injector durability and thus engine performance. Indicative results of flow simulations during the full injection event of a Diesel injector are presented. In addition to the Navier-Stokes equations, the enthalpy conservation equation is considered for predicting the fuel temperature. Cavitation is simulated using an Eulerian-Lagrangian cavitation model fully coupled with the flow equations. Compressible bubble dynamics based on the R-P equation also consider thermal effects. Variable fuel properties function of the local pressure and temperature are taken from literature and correspond to a reference so-called summer Diesel fuel. Fuel pressurisation up to 3000bar pressure is considered while various wall temperature boundary conditions are tested in order to compare their effect relative to those of the fuel heating caused during the depressurisation of the fuel as it passes through the injection orifices. The results indicate formation of strong temperature gradients inside the fuel injector while heating resulting from the extreme friction may result to local temperatures above the fuel's boiling point. Predictions indicate bulk fuel temperature increase of more than 100°C during the opening phase of the needle valve. Overall, it is concluded that such effects are significant for the injector performance and should be considered in relevant simulation tools.

  4. Energy wood. Part 2b: Wood pellets and pellet space-heating systems

    International Nuclear Information System (INIS)

    Nussbaumer, T.

    2002-01-01

    The paper gives an overview on pellet utilization including all relevant process steps: Potential and properties of saw dust as raw material, pellet production with drying and pelletizing, standardization of wood pellets, storage and handling of pellets, combustion of wood pellets in stoves and boilers and applications for residential heating. In comparison to other wood fuels, wood pellets show several advantages: Low water content and high heating value, high energy density, and homogeneous properties thus enabling stationary combustion conditions. However, quality control is needed to ensure constant properties of the pellets and to avoid the utilization of contaminated raw materials for the pellet production. Typical data of efficiencies and emissions of pellet stoves and boilers are given and a life cycle analysis (LCA) of wood pellets in comparison to log wood and wood chips is described. The LCA shows that wood pellets are advantageous thanks to relatively low emissions. Hence, the utilization of wood pellet is proposed as a complementary technology to the combustion of wood chips and log wood. Finally, typical fuel cost of wood pellets in Switzerland are given and compared with light fuel oil. (author)

  5. Displacement of cryomodule in CADS injector II

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Jiandong; Zhang, Bin; Wang, Fengfeng; Wan, Yuqin; Sun, Guozhen; Yao, Junjie; Zhang, Juihui; He, Yuan [Chinese Academy of Sciences, Lanzhou (China). Inst. of Modern Physics

    2017-06-15

    As Cryomodule can easily reduce higher power consumption and length of an accelerator and the accelerator can be operated more continuously. The Chinese academy of sciences institute of modern physics is developing an accelerator driven subcritical system (CADS) Injector II. Cryomodules are extremely complex systems, and their design optimization is strongly dependent on the accelerator application for which they are intended.

  6. Properties of high current RFQ injectors

    International Nuclear Information System (INIS)

    Schempp, A.; Goethe, J.W.

    1996-01-01

    RFQ linacs are efficient, compact low energy ion structures, which have found numerous applications. They use electrical rf focusing and can capture, bunch and transmit high current ion beams. Some recent development and new projects like a heavy ion injectors for a cyclotron, and the status of the work on high current high duty factor RFQs will be discussed. (author)

  7. Development of AMS high resolution injector system

    International Nuclear Information System (INIS)

    Bao Yiwen; Guan Xialing; Hu Yueming

    2008-01-01

    The Beijing HI-13 tandem accelerator AMS high resolution injector system was developed. The high resolution energy achromatic system consists of an electrostatic analyzer and a magnetic analyzer, which mass resolution can reach 600 and transmission is better than 80%. (authors)

  8. Acquisition system of tandem injector parameters

    International Nuclear Information System (INIS)

    Decourt, M.

    1986-01-01

    The system centralizes all the parameters belonging to the accelerator injector. The acquisition center system reinforces an original device made of cameras and video receivers. Besides giving access to all the parameters of the ion source, the new system allows, in the ''OSCILLO'' mode, to visualize in real time any channel on the oscilloscope [fr

  9. Bevalac injector final stage RF amplifier upgrades

    International Nuclear Information System (INIS)

    Howard, D.; Calvert, J.; Dwinell, R.; Lax, J.; Lindner, A.; Richter, R.; Ridgeway, W.

    1991-01-01

    With the assistance of the DOE In-house Energy Management Program, the Bevalac injector final stage RF amplifier systems have been successfully upgraded to reduce energy consumption and operating costs. This recently completed project removed the energy-inefficient plate voltage modulator circuits that were used in conjunction with the final stage RF amplifiers. Construction, design, and operating parameters are described in detail

  10. Properties of high current RFQ injectors

    Energy Technology Data Exchange (ETDEWEB)

    Schempp, A.; Goethe, J.W. [Frankfurt Univ. (Germany). Inst. fuer Angewandte Physik

    1996-12-31

    RFQ linacs are efficient, compact low energy ion structures, which have found numerous applications. They use electrical rf focusing and can capture, bunch and transmit high current ion beams. Some recent development and new projects like a heavy ion injectors for a cyclotron, and the status of the work on high current high duty factor RFQs will be discussed. (author) 2 refs.

  11. Spray analysis of the PFAMEN injector

    NARCIS (Netherlands)

    Reijnders, J.J.E.; Boot, M.D.; de Goey, L.P.H.; Bosi, M.; Postrioti, L.

    2013-01-01

    In an earlier study, a novel type of diesel fuel injector was proposed. This prototype injects fuel via porous (sintered) micro pores instead of via the conventional 6-8 holes. The micro pores are typically 10-50 micrometer in diameter, versus 120-200 micrometer in the conventional case. The

  12. Injector tip for an internal combustion engine

    Science.gov (United States)

    Shyu, Tsu Pin; Ye, Wen

    2003-05-20

    This invention relates to a the tip structure of a fuel injector as used in a internal combustion engine. Internal combustion engines using Homogeneous Charge Compression Ignition (HCCI) technology require a tip structure that directs fuel spray in a downward direction. This requirement necessitates a tip design that is capable of withstanding mechanical stresses associated with the design.

  13. Pellet-plasma interaction: Local disturbances caused by pellet ablation in tokamaks

    International Nuclear Information System (INIS)

    Lengyel, L.L.

    1989-01-01

    The local disturbance amplitudes caused by ablating pellets in tokamaks are computed in the framework of a magnetohydrodynamic model supplemented by the neutral gas plasma shielding ablation model. The model computes, for a given number of pellet particles locally deposited, the time histories of the ablatant cloud parameters, such as cloud radius, cloud length, electron density, temperature and cloud beta, at a succession of magnetic flux surfaces. The cloud radius thus determined may be fed back into the ablation model, thus adjusting the effect of the shielding cloud on the ablation rate. The model is applied to typical plasma parameter ranges of existing and planned tokamaks. The results show that the ablating pellets may cause massive local disturbances in tokamaks, depending upon the number of particles locally deposited. The peaks of these disturbances are of a spike nature, lasting only a few microseconds (Alfven time-scale). The characteristic decay time of the 'quasi-steady' disturbance values that characterize the after-spike period is of the order of several milliseconds (hydrodynamic time-scale). The peak electron density values may be as high as 10 23 to 10 25 m -3 , with the associated beta peaks exceeding unity. The 'quasi-steady' values of the electron density and the ablatant beta may be of the order of 10 22 to 10 24 m -3 and unity, respectively. Furthermore, the results show the strong dependence of the ablation rate on the dynamic characteristics of the ablatant cloud surrounding the pellet. (author). 25 refs, 6 figs, 2 tabs

  14. Processing of surrogate nuclear fuel pellets for better dimensional control with dry bag isostatic pressing

    Energy Technology Data Exchange (ETDEWEB)

    Hoggan, Rita E., E-mail: Rita.hoggan@inl.gov; Zuck, Larry D., E-mail: Larry.zuck@inl.gov; Cannon, W. Roger, E-mail: cannon@rutgers.edu; Lessing, Paul A., E-mail: p.a.l.2@hotmail.com

    2016-12-15

    A study of improved methods of processing fuel pellets was undertaken using ceria and zirconia/yttria/alumina as surrogates. Through proper granulation, elimination of fines and vertical vibration (tapping) of the parts bag prior to dry bag isostatic pressing (DBIP), reproducibility of diameter profiles among multiple pellets of ceria was improved by almost an order of magnitude. Reproducibility of sintered pellets in these studies was sufficient to allow pellets to be introduced into the cladding with a gap between the pellet and cladding on the order of 50 μm to 100 μm but not a uniform gap with tolerance of ±12 μm as is currently required. Deviation from the mean diameter along the length of multiple pellets, and deviation from roundness, decreased after sintering. This is not generally observed with dry pressed pellets. Sintered shrinkage was uniform to ±0.05% and thus, as an alternative, pellets may be machined to tolerance before sintering, thus avoiding the waste associated with post-sinter grinding. - Highlights: • Three methods of granule preparation for two different powder sources were outlined and compared using tap density curves. • A dry bag isostatic press was used to fabricate pellets and longer rods. Thus longer pellets could be fabricated by this technique. • Vertical vibrations to pack granules decreased variation in dimensions from pellet to pellet by a factor of nine. • Sintering shrinkage varied by only 0.1% along the length of a rod. Thus green machining prior to sintering could result in tight tolerances.

  15. Fuzzy control of the iron ore pellets thermal treatment on a conveying car

    Directory of Open Access Journals (Sweden)

    В’ячеслав Йосипович Лобов

    2017-07-01

    Full Text Available The purpose of this article is to solve the problem of fuzzy control of iron ore pellets thermal treatment on a conveyor roasting machine, to build an automated control system of conveyor roasting machine and perform simulation and to present the results of research. According to the structural scheme of the fuzzy control an automated control system is proposed for being modelled. This is done by using the software MATLAB. The use of atomic emission spectroscopy determines the percentage of the major elements in iron ore pellets considering the main process parameters. This article uses an automated system of fuzzy control of iron ore pellets firing on a conveyor roasting machine with the introduction of atomic emission spectroscopy of the pellets. Development and practical implementation of fuzzy control will improve their quality by taking into account the basic parameters of thermal treatment of pellets such as speed of movement of the grate trucks, gas flow rate, the height of the layer of pellets and the venting speed of the pellets layer with gas-air flow, humidity, average diameter, the basicity and the iron composition in the pellets. The expediency of the developed method of using automated fuzzy control system of iron ore pellets firing on a conveyor roasting car has been proved. The system with fuzzy controller provides a reduction on average 2 m3/h, which is 0,3% of natural gas consumption as compared to the existing systems. This provides more uniform gas permeability of the layer of pellets, which leads to filtration rate increase of the gas flow and to heat exchange intensification in the layer of pellets. It makes it possible to introduce the atomic emission spectroscopy of non-burned pellets and to increase the productivity of conveyor roasting machine by 2,5%. At the same time the resistance of technological equipment (pallets increases, due to more uniform distribution of the thermal field

  16. Triaxial Swirl Injector Element for Liquid-Fueled Engines

    Science.gov (United States)

    Muss, Jeff

    2010-01-01

    A triaxial injector is a single bi-propellant injection element located at the center of the injector body. The injector element consists of three nested, hydraulic swirl injectors. A small portion of the total fuel is injected through the central hydraulic injector, all of the oxidizer is injected through the middle concentric hydraulic swirl injector, and the balance of the fuel is injected through an outer concentric injection system. The configuration has been shown to provide good flame stabilization and the desired fuel-rich wall boundary condition. The injector design is well suited for preburner applications. Preburner injectors operate at extreme oxygen-to-fuel mass ratios, either very rich or very lean. The goal of a preburner is to create a uniform drive gas for the turbomachinery, while carefully controlling the temperature so as not to stress or damage turbine blades. The triaxial injector concept permits the lean propellant to be sandwiched between two layers of the rich propellant, while the hydraulic atomization characteristics of the swirl injectors promote interpropellant mixing and, ultimately, good combustion efficiency. This innovation is suited to a wide range of liquid oxidizer and liquid fuels, including hydrogen, methane, and kerosene. Prototype testing with the triaxial swirl injector demonstrated excellent injector and combustion chamber thermal compatibility and good combustion performance, both at levels far superior to a pintle injector. Initial testing with the prototype injector demonstrated over 96-percent combustion efficiency. The design showed excellent high -frequency combustion stability characteristics with oxygen and kerosene propellants. Unlike the more conventional pintle injector, there is not a large bluff body that must be cooled. The absence of a protruding center body enhances the thermal durability of the triaxial swirl injector. The hydraulic atomization characteristics of the innovation allow the design to be

  17. Test of a small domestic boiler using different pellets

    International Nuclear Information System (INIS)

    Dias, J.; Costa, M.; Azevedo, J.L.T.

    2004-01-01

    This paper presents results from an experimental study performed on a 13 kW th commercial domestic boiler using pellets as fuel. Four different types of pellets were used and, for each one, the boiler was tested as a function of its capacity and the fan regulation affecting excess air. Measurements were performed for boiler heat load, pellet consumption rate, flue-gas temperature and composition. Mass balances allowed the calculation of the flue-gas flow rate and associated heat losses. Losses from incomplete combustion have also been quantified. Under boiler steady-state conditions the flue-gas O 2 concentration changes with boiler load and ventilation due to the regulation scheme of the boiler. Flue-gas CO shows a minimum for values of O 2 in the flue-gases of about 13%. NO x emissions are independent of excess air for low values of nitrogen in the fuel whereas, for larger values, NO x emissions increase with the O 2 present in the combustion products. The fractional conversion of the pellet nitrogen into NO x is in line with literature data. The boiler start-up was characterised by the temperature evolution inside and above the bed showing the propagation of combustion in the bed during about 10 min. During boiler start-up, a maximum in CO emissions was observed which is associated with the maximum combustion intensity, as typified by the flue-gas O 2 concentration and temperature, regardless the pellet type. (Author)

  18. Comparative analysis of thermal behavior in hollow nuclear fuel pellets

    International Nuclear Information System (INIS)

    Santos, Beatriz M. dos; Alvim, Antonio C.M.

    2017-01-01

    The increase in energy demand in Brazil and in the world is a real problem and several solutions are being considered to mitigate it. Maximization of energy generation, within the safety standards of fuel resources already known, is one of them. In this respect, nuclear energy is a crucial technology to sustain energy demand on several countries. Performances of a solid cylindrical and an annular rod have been verified and compared; where it has been proven that the annular rod can reach a higher nominal power in relation to the solid one. In this paper, the temperature profiles of two distinct nuclear fuel pellets, one of them annular and the other in the shape of a hollow biconcave disc (like the cross section of a red blood cell), were compared to analyze the efficiency and safety of both. The finite differences method allowed the evaluation of the thermal behavior of these pellets, where one specific physical condition was analyzed, regarding convection and conduction at the lateral edges. The results show that the temperature profile of the hollow biconcave disc pellet is lower, about 70 deg C below, when compared to the temperature profile of the annular pellet, considering the same simulation parameters for both pellets. (author)

  19. Dynamic hohlraum and ICF pellet implosion experiments on Z

    International Nuclear Information System (INIS)

    Nash, T.J.; Derzon, M.S.; Chandler, G.A.

    1999-01-01

    By stabilizing an imploding z-pinch on Z (20 MA, 100 ns) with a solid current return can and a nested wire array the authors have achieved dynamic hohlraum radiation temperatures over 200 eV at a diameter of approximately 1 mm. The pinch configuration yielding this temperature is a nested tungsten wire array of 240 and 120 wires at 4 and 2 cm diameters weighing 2 and 1 mg, 1 cm long, imploding onto a 5 mm diameter, 14 mg/cc cylindrical CH foam, weighing 3 mg. They have used a single 4 cm diameter tungsten wire array to drive a 1.6 mm diameter ICF capsule mounted in a 6 mg/cc foam inside a 3 mg copper annulus at 5 mm diameter, and measured x-ray emissions indicative of the pellet implosion. Mounting the pellet in foam may have caused the hohlraum to become equator-hot. They will present results from upcoming pellet experiments in which the pellet is mounted by thread and driven by a larger diameter, 6 or 7 mm, copper annulus to improve radiation drive symmetry. They will also discuss designs for tapered foam annular targets that distort a cylindrical pinch into a quasi-sphere that will wrap around an ICF pellet to further improve drive symmetry

  20. Comparative analysis of thermal behavior in hollow nuclear fuel pellets

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Beatriz M. dos; Alvim, Antonio C.M., E-mail: bmachado@nuclear.ufrj.br, E-mail: aalvim@gmail.com [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2017-11-01

    The increase in energy demand in Brazil and in the world is a real problem and several solutions are being considered to mitigate it. Maximization of energy generation, within the safety standards of fuel resources already known, is one of them. In this respect, nuclear energy is a crucial technology to sustain energy demand on several countries. Performances of a solid cylindrical and an annular rod have been verified and compared; where it has been proven that the annular rod can reach a higher nominal power in relation to the solid one. In this paper, the temperature profiles of two distinct nuclear fuel pellets, one of them annular and the other in the shape of a hollow biconcave disc (like the cross section of a red blood cell), were compared to analyze the efficiency and safety of both. The finite differences method allowed the evaluation of the thermal behavior of these pellets, where one specific physical condition was analyzed, regarding convection and conduction at the lateral edges. The results show that the temperature profile of the hollow biconcave disc pellet is lower, about 70 deg C below, when compared to the temperature profile of the annular pellet, considering the same simulation parameters for both pellets. (author)

  1. ORNL neutral gas shielding model for pellet-plasma interactions

    International Nuclear Information System (INIS)

    Milora, S.L; Foster, C.A.

    1977-05-01

    A revised neutral molecule ablation model is derived to describe the evaporation of a solid hydrogen pellet in a tokamak plasma. The approach taken is based on the theory of Parks, Turnbull, and Foster who postulate that a cloud of molecular hydrogen surrounding the pellet shields the surface from incoming energetic electrons and, in so doing, regulates the evaporation rate. This treatment differs from an earlier model in that the hydrodynamic behavior of the molecular cloud is treated in a self-consistent manner. Numerical solutions of the fluid dynamic equations, which include the effects of strong electron heating locally in the gas, reveal that the flow of material away from the pellet is initially retarded by the heating and then rapidly accelerated and rarefied. This behavior is more pronounced for higher temperature plasmas and the net effect is that pellet lifetimes are prolonged slightly by including the heating effects. A comparison is made with the results of the recent pellet injection experiments on ORMAK and a simple injection depth scaling law is derived

  2. Investigation of pellet acceleration by an arc heated gas gun

    International Nuclear Information System (INIS)

    Andersen, S.A.; Baekmark, L.; Jensen, V.O.; Michelsen, P.; Weisberg, K.V.

    1988-10-01

    This report describes work on pellet acceleration by means of an arc heated gas gun. Preliminary results were described in Riso-M-2536 and in Riso-M-2650. This final report describes the work carried out from 1987.03.31 to 1988.09.30. An arc heated hydrogen gas source, for pneumatic acceleration of deuterium pellets to velocities above 2 km/s, was developed. Experiments were performed with an arc chamber to which different methods of hydrogen supply were possible, and to which the input of electrical power could be programmed. Results in terms of pressure transients and acceleration curves are presented. Maximum pellet velocities approaching 2 km/s were obtained. This limit is discussed in relation to the presented data. Finally this report contains a summary and a conclusion for the entire project. (author) 34 ills., 3 refs

  3. Management of high current transients in the CWDD Injector 200 kV power system

    International Nuclear Information System (INIS)

    Carwardine, J.A.; Pile, G.; Zinneman, T.E.

    1993-01-01

    The injector for the Continuous Wave Deuterium Demonstrator is designed to deliver a high current CW negative deuterium ion beam at an energy of 200 keV to a Radio Frequency Quadrupole. The injector comprises a volume ion source, triode accelerator, high-power electron traps and low-energy beam transport with a single focusing solenoid. Some 75 Joules of energy are stored in stray capacitance around the high voltage system and discharged in a few microseconds following an injector breakdown. In order to limit damage to the accelerator grids, a magnetic snubber is incorporated to absorb most of the energy. Nevertheless, large current transients flow around the system as a result of an injector breakdown; these have frequently damaged power components and caused spurious behavior in many of the supporting systems. The analytical and practical approaches taken to minimize the effects of these transients are described. Injector breakdowns were simulated using an air spark gap and measurements made using standard EMC test techniques. The power circuit was modeled using an electrical simulation code; good agreement was reached between the model and measured results

  4. Recycling process of Mn-Al doped large grain UO2 pellets

    International Nuclear Information System (INIS)

    Nam, Ik Hui; Yang, Jae Ho; Rhee, Young Woo; Kim, Dong Joo; Kim, Jong Hun; Kim, Keon Sik; Song, Kun Woo

    2010-01-01

    To reduce the fuel cycle costs and the total mass of spent light water reactor (LWR) fuels, it is necessary to extend the fuel discharged burn-up. Research on fuel pellets focuses on increasing the pellet density and grain size to increase the uranium contents and the high burnup safety margins for LWRs. KAERI are developing the large grain UO 2 pellet for the same purpose. Small amount of additives doping technology are used to increase the grain size and the high temperature deformation of UO 2 pellets. Various promising additive candidates had been developed during the last 3 years and the MnO-Al 2 O 3 doped UO 2 fuel pellet is one of the most promising candidates. In a commercial UO 2 fuel pellet manufacturing process, defective UO 2 pellets or scraps are produced and those should be reused. A common recycling method for defective UO 2 pellets or scraps is that they are oxidized in air at about 450 .deg. C to make U 3 O 8 powder and then added to UO 2 powder. In the oxidation of a UO 2 pellet, the oxygen propagates along the grain boundary. The U 3 O 8 formation on the grain boundary causes a spallation of the grains. So, size and shape of U 3 O 8 powder deeply depend on the initial grain size of UO 2 pellets. In the case of Mn-Al doped large grain pellets, the average grain size is about 45μm and about 5 times larger than a typical un-doped UO 2 pellet which has grain size of about 8∼10μm. That big difference in grain size is expected to cause a big difference in recycled U 3 O 8 powder morphology. Addition of U 3 O 8 to UO 2 leads to a drop in the pellet density, impeding a grain growth and the formation of graph- like pore segregates. Such degradation of the UO 2 pellet properties by adding the recycled U 3 O 8 powder depend on the U 3 O 8 powder properties. So, it is necessary to understand the property and its effect on the pellet of the recycled U 3 O 8 . This paper shows a preliminary result about the recycled U 3 O 8 powder which was obtained by

  5. Development of wood pellets market in South East Europe

    Directory of Open Access Journals (Sweden)

    Glavonjić Branko D.

    2015-01-01

    Full Text Available The paper presents the results of researching wood pellets market in nine countries in South East Europe and Slovakia. Objective of the research was to observe the actual situation regarding the number of producers, size of installed capacities, production volume, foreign trade flows and existing problems and obstacles which significantly limit the sustainable development of wood pellets market in the selected countries. Selection of such an objective results from the fact that according to the stated elements there are no sufficiently reliable data, wherefore this region is a huge gap in numerous reports of international and national organizations and institutions. Results of the conducted research show that in the middle of 2014, 245 producers were engaged in wood pellets production in South East Europe and Slovakia, 116 of which were located in Bulgaria and Serbia. Most of the producers of wood pellets has installed capacities of 1,000-5,000 tons annually, while only 18 factories in the entire region have the installed capacity over 30,000 tons/year. Observed collectively in all stated countries, the total installed capacities for wood pellets production were 2.2 million tons in 2013 and the realized production was 1.36 million tons. The largest part of the produced amounts of wood pellets in this region is exported. 1.06 million tons were exported from the region in 2013, which is 77.9% of the realized production. Such high export is the result of the underdevelopment of the local market (Slovenia is the only exception and the problems which exist and limit its faster development in most countries.

  6. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor refueling: Technical progress report

    International Nuclear Information System (INIS)

    Kim, K.

    1986-01-01

    A detailed experimental study successfully demonstrates the acceleration of frozen hydrogen pellets by means of a fuseless two-stage electromagnetic railgun system. This system consists of a pneumatic hydrogen pellet injector, which freezes and pneumatically pre-accelerates (with high-pressure helium as the propellant gas) cylindrical 1.6-mm-dia by 2.15-mm-long hydrogen pellets, and a 60-cm-long, 1.6-mm-dia circular-bore electromagnetic railgun. The pellet is introduced into the railgun by means of a coupling piece, and a plasma-arc armature is created from the propellant gas by means of a very unique, fuseless, arc-initiation scheme. Railgun-accelerated hydrogen pellet velocities in excess of 1.6 km/s are achieved from pneumatically accelerated injection velocities of 800 m/s. Streak-camera and current-probe data show that the plasma-arc armature moves at a velocity proportional to the railgun current, I. Insight to this I-dependence is gained through the use of streak photography and current probes for varying bore geometries and gas pressures

  7. Achromatic beam transport of High Current Injector

    International Nuclear Information System (INIS)

    Kumar, Sarvesh; Mandal, A.

    2016-01-01

    The high current injector (HCI) provides intense ion beams of high charge state using a high temperature superconducting ECR ion source. The ion beam is accelerated upto a final energy of 1.8 MeV/u due to an electrostatic potential, a radio frequency quadrupole (RFQ) and a drift tube linac (DTL). The ion beam has to be transported to superconducting LINAC which is around 50 m away from DTL. This section is termed as high energy beam transport section (HEBT) and is used to match the beam both in transverse and longitudinal phase space to the entrance of LINAC. The HEBT section is made up of four 90 deg. achromatic bends and interconnecting magnetic quadrupole triplets. Two RF bunchers have been used for longitudinal phase matching to the LINAC. The ion optical design of HEBT section has been simulated using different beam dynamics codes like TRACEWIN, GICOSY and TRACE 3D. The field computation code OPERA 3D has been utilized for hardware design of all the magnets. All the dipole and quadrupole magnets have been field mapped and their test results such as edge angles measurements, homogeneity and harmonic analysis etc. are reported. The whole design of HEBT section has been performed such that the most of the beam optical components share same hardware design and there is ample space for beam diagnostics as per geometry of the building. Many combination of achromatic bends have been simulated to transport the beam in HEBT section but finally the four 90 deg. achromatic bend configuration is found to be the best satisfying all the geometrical constraints with simplified beam tuning process in real time

  8. EFFECT OF INJECTOR OPENING PRESSURE ON PERFORMANCE AND EMISSION OF LPG - METHYL ESTER OF MAHUA OIL DUAL FUEL ENGINE

    Directory of Open Access Journals (Sweden)

    N. Kapilan

    2017-11-01

    Full Text Available One of variables, which affect the performance and emission of dual fuel engine is injection pressure. Hence in the present work, effect of Injector opening pressure on the performance of the engine was studied.  A four stroke single cylinder engine was modified to work in dual fuel mode. Three injector opening pressures (180 bar, 200 bar and 220 bar were considered for the present work. Methyl ester of mahua oil was used as pilot fuel and LPG was used as primary fuel.    From the test results, it was observed that the injector opening pressure of 200 bar results in higher brake thermal efficiency. The higher injector opening pressure results in better atomization and peneatration of methyl ester of mahua oil. The exhaust emissions such as Smoke, unburnt hydro carbon and carbon monoxide of 200 bar is lower than other pressures.

  9. Numerical Study of Flow Characteristics in a Solid Particle Incinerator for Various Design Parameters of Injectors

    Energy Technology Data Exchange (ETDEWEB)

    Son, Jin Woo; Kim, Su Ho; Sohn, Chae Hoon [Sejong Univ., Seoul (Korea, Republic of)

    2013-12-15

    The flow characteristics in a solid particle incinerator are investigated numerically for high burning rate of wastes. The studied incinerator employs both a swirl flow used in the furnace of power plants and a design concept applied to a rocket combustor. As the first step, the non-reactive flow field is analyzed in the incinerator with primary and secondary injectors through which solid fuel and air are injected. The deflection angle of a primary injector, inclination angle of a secondary injector, and gap between the two types of injectors are selected as design parameters. The swirl number is adopted for evaluating the degree of swirl flow and estimated over wide ranges of three parameters. The swirl number increases with deflection angle, but it is affected little by inclination angle. Recirculation zones are formed near the injectors, and their size affects the swirl number. The swirl number decreases with the zonal size of recirculation. From the numerical results, the design points can be found with strong swirl flow.

  10. Numerical investigation of injector geometry effects on fuel stratification in a GCI engine

    KAUST Repository

    Atef, Nour; Badra, Jihad; Jaasim, Mohammed; Im, Hong G.; Sarathy, Mani

    2017-01-01

    Injectors play an important role in direct injection (DI) gasoline compression ignition (GCI) engines by affecting the in-cylinder mixture formation and stratification, which in turn impacts combustion and emissions. In this work, the effects of two different injector geometries, a 7-hole solid-cone injector and an outwardly opening hollow-cone injector, on fuel mixture stratification in a GCI engine were investigated by computational simulations. Three fuels with similar autoignition kinetics, but with different physical properties, were studied to isolate the effect of the combustion chemistry on combustion phasing. In addition, start of injection (SOI) sweeps relevant to low-load engine operating conditions were performed. The results show that physical properties of the fuel do not have significant influence when using a hollow-cone injector. Richer mixtures were observed at all the studied SOI (−40 to −14 CAD aTDC) cases, which can be attributed to the nature of the hollow cone spray. At later SOIs (−18 and −14 CAD aTDC), the richer mixtures are accompanied by lower mean in-cylinder temperature due to the charge cooling effect, which surpasses the equivalence ratio effect. The effect of fuel physical properties on combustion phasing was evident in multi-hole injection cases, which can be attributed to the differences in mixture stratification and equivalence ratio distribution at the time of ignition.

  11. Simulation of Assembly Tolerance and Characteristics of High Pressure Common Rail Injector

    Directory of Open Access Journals (Sweden)

    Jiping Lu

    2011-12-01

    Full Text Available Fuel injector is the key part of a high-pressure common rail fuel injection system. Its manufacturing precision and assembly quality affect system's property and performance. According to the characteristics and demands of assembly of the fuel injector, an intelligent optimization algorithm is proposed to resolve the problem of assembly sequence planning. Based on geometric modeling, assembly dimension chain of the injector control chamber is established, and the relationship between assembly tolerance and volume change of control chamber is analyzed. The optimization model of the assembly is established. The impact of assembly tolerance on injector's performance is simulated according to the optimization algorithm. The simulation result shows that quantity of injection fuel changes correspondingly with the change of assembly tolerance, while injection rate and pressure do not change significantly, and the response rate of needle considerably slow. Similarly, the leakage rate of fuel in control chamber is calculated, indicating that the assembly tolerance has obvious impact on fuel leakage and its rate. The study illuminates that injector's assembly tolerance has prominent effect on injection.

  12. Numerical investigation of injector geometry effects on fuel stratification in a GCI engine

    KAUST Repository

    Atef, Nour

    2017-11-24

    Injectors play an important role in direct injection (DI) gasoline compression ignition (GCI) engines by affecting the in-cylinder mixture formation and stratification, which in turn impacts combustion and emissions. In this work, the effects of two different injector geometries, a 7-hole solid-cone injector and an outwardly opening hollow-cone injector, on fuel mixture stratification in a GCI engine were investigated by computational simulations. Three fuels with similar autoignition kinetics, but with different physical properties, were studied to isolate the effect of the combustion chemistry on combustion phasing. In addition, start of injection (SOI) sweeps relevant to low-load engine operating conditions were performed. The results show that physical properties of the fuel do not have significant influence when using a hollow-cone injector. Richer mixtures were observed at all the studied SOI (−40 to −14 CAD aTDC) cases, which can be attributed to the nature of the hollow cone spray. At later SOIs (−18 and −14 CAD aTDC), the richer mixtures are accompanied by lower mean in-cylinder temperature due to the charge cooling effect, which surpasses the equivalence ratio effect. The effect of fuel physical properties on combustion phasing was evident in multi-hole injection cases, which can be attributed to the differences in mixture stratification and equivalence ratio distribution at the time of ignition.

  13. An Experimental Study of Emission and Combustion Characteristics of Marine Diesel Engine with Fuel Injector Malfunctions

    Directory of Open Access Journals (Sweden)

    Kowalski Jerzy

    2016-01-01

    Full Text Available The presented paper shows the results of the laboratory study on the relation between chosen malfunctions of a fuel injector and composition of exhaust gas from the marine engine. The object of research is a marine 3-cylinder, four-stroke, direct injection diesel engine with an intercooler system. The engine was loaded with a generator and supercharged. The generator was electrically connected to the water resistance. The engine operated with a load between 50 kW and 250 kW at a constant speed. The engine load and speed, parameters of the turbocharger, systems of cooling, fuelling, lubricating and air exchange, were measured. Fuel injection and combustion pressures in all cylinders of the engine were also recorded. Exhaust gas composition was recorded by using a electrochemical gas analyzer. Air pressure, temperature and humidity were also recorded. Emission characteristics of the engine were calculated according to ISO 8178 standard regulations. During the study the engine operated at the technical condition recognized as „working properly” and with simulated fuel injector malfunctions. Simulation of malfunctions consisted in the increasing and decreasing of fuel injector static opening pressure, decalibration of fuel injector holes and clogging 2 neighboring of 9 fuel injector holes on one of 3 engine cylinders.

  14. Transport analysis of pellet-enhanced ICRH plasma in JET

    International Nuclear Information System (INIS)

    Hammett, G.W.; Colestock, P.L.; Granetz, R.S.; McCune, D.C.; Phillips, C.K.; Schmidt, G.L.; Smithe, D.N.; Kupschus, P.

    1989-01-01

    Performance of JET ICRH heated discharges has been significantly enhanced by using pellet fueling to produce a peaked density target for ICRH. The central T i is observed to increase by up to 80%, central T e by up to 40%, and the neutron rate by up to 400%, over their no-pellet values (which are already in the enhanced 'monster-sawtooth' regime). In this paper we describe the transport analysis of these discharges using the TRANSP code. These results indicate that the thermal diffusivities χ i and χ e are reduced by a factor of ∼2 near the plasma center where the pellets have increased the density gradient. The paper focuses on JET discharge 16211 which is documented more fully in a companion paper. (author) 6 refs., 8 figs

  15. Ultrasonic analysis of UO{sub 2} pellets

    Energy Technology Data Exchange (ETDEWEB)

    Bittencourt, Marcelo de S.Q.; Baroni, Douglas B.; Martorelli, Daniel S., E-mail: bittenc@ien.gov.br, E-mail: douglasbaroni@ien.gov.br, E-mail: daniel@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Ultrassom; Dias, Fabio C.; Silva, Jose W.S. da, E-mail: fabio@ird.gov.br, E-mail: wanderley@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Salvaguardas

    2013-07-01

    Ceramic materials have been widely used for various purposes in many different industries due to certain characteristics, such as high melting point and high resistance to corrosion. In the nuclear area, ceramics are of great importance due to the process of fabrication of fuel pellets for nuclear reactors. Generally, high accuracy destructive techniques are used to characterize nuclear materials for fuel fabrication. These techniques usually require costly equipment and facilities, as well as experienced personnel. This paper aims at presenting an analysis methodology for UO2 pellets using a non-destructive ultrasonic technique for porosity measurement. This technique differs from traditional ultrasonic techniques in the sense it uses ultrasonic pulses in frequency domain instead of time domain. Therefore, specific characteristics of the analyzed material are associated with the obtained frequency spectrum. In the present work, four fuel grade UO2 pellets were analyzed and the corresponding results evaluated. (author)

  16. A model for radial cesium transport in a fuel pellet

    International Nuclear Information System (INIS)

    Imoto, Shosuke

    1989-01-01

    In order to explain the radial redistribution of cesium in an irradiated pellet, a two-step release model is proposed. The first step involves the migration of cesium by atomic diffusion to some channels, such as grain boundaries and cracks, and the second step assumes a thermomigration down along the temperature gradient. Distribution profiles of cesium are obtained by numerical calculation with the present model assuming a constant and spatially uniform birth rate of cesium in the pellet. The result agrees well with the profile observed by micro-gamma scanning for the LWR fuel in the outer region of the pellet but diverges from it at the inner region. Discussion is made on the steady-state model hitherto generally utilized. (orig.)

  17. Application of EMILAC to pellet injection

    International Nuclear Information System (INIS)

    Iwamura, Yasuhiro; Yamasaki, Takao; Nakamura, Hirone; Hashimoto, Mitsuo; Miya, Kenzo

    1987-01-01

    A new type of electromagnetic accelerator for pellet injection is proposed. Projectile of cylinder shape is accelerated with the repulsive force generated by a combination of two coils, which are different in purpose. And the accelerator is named EMILAC (Electro-Magnetic Inductive Linear Accelerator). In this paper, we investigate the method of applying EMILAC to pellet injection, and calculate the ablation rate of pellet. (author)

  18. Modeling drying of iron ore pellets

    OpenAIRE

    Ljung, Anna-Lena

    2010-01-01

    Iron ore pellets are a highly refined product supplied to the steel making industry for use in blast furnaces or direct reduction processes. The use of pellets offers many advantages such as customer adopted products, transportability and mechanical strength yet the production is time and energy consuming. Being such, there is a natural driving force to enhance the pelletization in order to optimize production and improve quality. The aim with this thesis is to develop numerical models with w...

  19. Two-pulse acceleration for BEPCII injector linac

    International Nuclear Information System (INIS)

    Pei Shilun; Wang Shuhong; Lu Weibin

    2007-01-01

    In order to double the injection rate of positron beam from the linac to the storage ring of BEPC II, a two-pulse generation and acceleration scheme has been proposed. The two-pulse simulation by programs including LIAR, PARMELA, EGUN and TRANSPORT is described first and the method is applied in the beam dynamics studies of BEPC II linac. The experiment of two-pulse acceleration was performed in BEPC II linac and some preliminary results are obtained, which provides a good reference for further upgrading of BEPC II injector linac. (authors)

  20. IONS FOR LHC STATUS OF THE INJECTOR CHAIN

    CERN Document Server

    Manglunki, Django; Borburgh, J; Carli, C; Chanel, M; Dumas, L; Fowler, T; Gourber-Pace, M; Hancock, S; Hourican, M; Jowett, John M; Küchler, D; Mahner, E; Martini, M; Maury, S; Pasinelli, S; Raich, U; Rey, A; Royer, J-P; Scrivens, R; Sermeus, L; Tranquille, G; Vallet, J L; Vandorpe, B

    2007-01-01

    The LHC will, in addition to proton runs, be operated with Pb ions and provide collisions at energies of 5.5 TeV per nucleon pair, i.e. more than 1.1 PeV per event, to experiments. The transformation of CERN's ion injector complex (Linac3-LEIR-PS-SPS) to allow collision of ions in LHC in 2008 is well under way. The status of these modifications and the latest results of commissioning will be presented. The remaining challenges are reviewed.