Ms
Elena de la Luna
(EU)
12/10/2012, 08:30
Poster
Since ITER is expected to operate at powers close to the H-mode threshold power scaling, it is important for ITER predictions to investigate the confinement and plasma dynamics in H-modes for heating powers marginally above the H-mode threshold power (P_{L-H}). The JET experience is that such operation leads to a transient behavior of the H-mode, with transitions from Type I ELMs to Type III...
Mr
Larry R. Baylor
(USA)
12/10/2012, 08:30
Poster
Pellet pacing of edge localized modes (ELMs), which is the triggering of rapid small ELMs by pellet injection, has been proposed as a method to prevent large ELMs that can erode the ITER plasma facing components [1]. D_2 pellet injection has been used on the DIII-D tokamak to successfully demonstrate for the first time the pacing of ELMs at a 10x higher rate than natural ELMs. The...
Mr
Weiwen Xiao
(China)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
New experimental results of ELM mitigation by supersonic molecular beam injection (SMBI) are report in HL-2A and KSTAR. The experiments show that ELM frequency increase (f_ELM^SMBI/f_ELM^0~ 2-3.5) and an ELM amplitude decrease for a finite duration period during an SMBI influence time, tau_I. Pedestal density profiles were relaxed by SMBI and recovered gradually during tau_I. This indicates...
Mr
Chengyuan Chen
(China)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
For a tokamak fusion reactor, the mitigation of Edge Localized Mode (ELM) is likely a mandatory requirement to avoid excessive erosion of the divertor targets and yet exploit the benefits of high confinement mode operation [1]. It is reported that pellets could trigger ELM when injected in type-I ELMy H-mode and ELM pacing has been accomplished with small multi-pellets injection [2]. Resonant...
Mr
Stanley Kaye
(USA)
12/10/2012, 08:30
Poster
Understanding the dependence of confinement on collisionality in tokamaks is important
for the design of next-step devices, which will operate at collisionalities at least one order of magnitude lower than in present generation. A wide range of collisionality has been obtained in the National Spherical Torus Experiment (NSTX) by employing two different wall conditioning techniques one with...
Mr
Kaijun Zhao
(China)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
New meso-scale electric fluctuations (MSEFs), having two components of n=0 and m/n=6/2 potential fluctuations, are first identified in the edge plasmas of a tokamak. The MSEFs coexist and interact with the magnetic fluctuations with two components of n=0 and m/n=6/2 (magnetic islands). The MSEFs also coexist and interplay with turbulence and low frequency zonal flow. The MSEFs mainly modulate...
Mr
Min Xu
(China)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
We report the first experimental evidence that turbulent eddies mediate the particle, momentum and vorticity transport at the edge of a tokamak plasma so as to amplify the shear layer at the last closed flux surface (LCFS). We find that turbulent eddies with relative negative vorticity (opposite to B field) and positive azimuthal momentum (electron-diamagnetic drift direction) are drawn from...
Mr
Anthony Field
(UK)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Ion thermal transport in spherical tokamaks is often observed to be close to the neo-classical level, which is consistent with the suppression of anomalous transport due to ion-scale turbulence by strong NBI-driven flow shear. In order to test this conjecture a 2D BES diagnostic has been implemented on MAST to image the low-k (< 1.6 cm^-1) density turbulence. Initial investigations have...
Mr
Yang Ren
(USA)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Microturbulence is considered to be a major candidate in driving anomalous transport in fusion plasmas, and the equilibrium ExB shear generated by externally driven flow can be a powerful tool to control microturbulence in future fusion devices such as FNSF and ITER. Here we present the first observation of the change in electron-scale turbulence wavenumber spectrum (measured by a high-k...
Mr
Kenji Tanaka
(Japan)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
In LHD, an H-mode transition was achieved after ELM suppression. The main plasma of LHD is surrounded by a thick ergodic layer, of width around 30 percent of the minor radius. This ergodic layer consists of m/n=10/10 and m/n=20/22 magnetic islands. This three dimensional structure of the edge magnetic field is similar to resonant magnetic perturbations (RMP) in tokamaks, so these results may...
Ms
Natalia Kosolapova
(France)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Radial correlation reflectometry (RCR) [1] is a microwave scattering technique for measuring the properties of electron density fluctuations in tokamaks. The coherence decay of two scattering signals with growing difference of probing frequencies is studied by the diagnostic to determine the turbulence radial wave number spectrum and the turbulence correlation length.
As it was shown already...
Ms
Zheng Yan
(USA)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Understanding the physics of the L-H transition power threshold scaling dependencies on toroidal field and density [1] is critical to operating and optimizing the performance of ITER. Measurements of long-wavelength (k_perp \rho_I<1)turbulent eddy dynamics, characteristics, flows, and flow shear in the near edge region of DIIID plasmas have been obtained during an ion gyro-radius scan (varying...
Mr
George R. McKee
(USA)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Long wavelength turbulence increases dramatically in the outer regions of DIII-D plasmas with the application of radial resonant magnetic field perturbations (RMP) to suppress edge-localized modes (ELMs). Correspondingly, transport increases and global energy confinement decreases in these low collisionality RMP-ELM suppressed discharges. This process is evident through a sharp reduction in...
Mr
Jiaqi Dong
(China)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
The generation mechanisms as well as the spatial and spectral characteristics of three dimensional large-scale coherent structures (LSCSs) in the form of blobs or filaments, stretching along magnetic field lines in the edge plasmas of the HL-2A tokamak are investigated using 10-tip poloidal and 8-tip radial probe arrays toriodally separated by 2100 mm [1,2]. The LSCSs in frequency range of 15...
Mr
Yuan Huang
(China)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
H-mode operation is extremely important and has been chosen as the standard operation scenario for ITER to meet its objectives, but the physical mechanism of H-mode access has not been fully understood and the power threshold for the L- H transition remains uncertainty. L-H transition induced by pellet injection has been studied on DIII-D, in which process the intermediate phase (I-phase) is...
Mr
Christopher Holland
(USA)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
A series of carefully designed validation experiments have been conducted on DIII-D to rigorously test gyrofluid and gyrokinetic predictions of transport and turbulence stiffness in both the ion and electron channels. In the first experiment, the ratio of the volume-averaged electron temperature profile to its value at rho=0.84 was found to be essentially invariant with increased heating over...
Mr
Troy Carter
(USA)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
The edge and scrape-off-layer region of tokamaks has a direct and important impact on overall performance of these devices: e.g. because of stiffness in core transport, the pedestal pressure directly impacts fusion power in burning plasma experiments. Developing first-principles understanding of and a predictive capability for processes in the edge region is critically important to ensure the...
Mr
Zixi Liu
(China)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Stationary edge localized modes (ELM) H-mode plasmas have been achieved on Experimental Advanced Superconducting Tokamak (EAST) by Low Hybrid Wave (PLHW ~1MW at 2.45 GHz) in 2010. This kind of ELMy H-mode has been studied. Threshold power increases with plasma density, and decreases with the distance between the X-point and the divertor surface on EAST. The minimum threshold power is about 0.9...
Mr
Vladimir Vershkov
(Russian Federation)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Two approaches for plasma diffusion studies were compared: low perturbation technique of periodic puff (dn/n_e = 0.3%) and strong puff (dn/n_e < 50%). Core density perturbations can be described in the model with constant in time–constant diffusion coefficients and pinch velocities, while at the edge this model failed. Three phases were distinguished in discharges with strong gas puff....
Mr
Zhongbing Shi
(China)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Experiments with nonlocal effect have been performed by using supersonic molecular beam injection (SMBI) in the case of the low density operation on the HL-2A tokamak. The increase in central electron temperature by the perturbations can be prolonged to about 100 ms by using repetitive SMBI with density control. A nearly relation between the central temperature rise and the edge perturbation...
Mr
Baonian Wan
(Institute of Plasma Physics)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
In low density (HL-2A) and lithium wall condition (HT-7) two coherent modes are discovered of the GAM frequency range only on potential signals, i.e. at 11kHz and 18kHz, which are symmetric for their poloidal and toroidal mode number n=m=0. So we can conclude that both two coherent modes are GAMs, named LFGAM and HFGAM respectively.
The results show that the amplitudes of LFZF and HFGAM...
Mr
John Canik
(Oak Ridge National Laboratory)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
The application of lithium coatings to the plasma-facing components (PFCs) of the National Spherical Torus Experiment (NSTX) has been shown to strongly impact plasma performance, improving energy confinement and eliminating ELMs. The pedestal structure is strongly affected by lithium: in discharges with lithium coatings, the density pedestal widens, and the electron temperature (Te) gradient...
Mr
Lothar Schmitz
(USA)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Understanding the formation dynamics of core and edge transport barriers is crucial for extrapolating present tokamak performance to burning plasma regimes. We present here direct evidence of low frequency Zonal Flows (ZF) reducing electron-scale turbulence in an electron internal transport barrier (ITB) at the q=2 rational surface, and periodically suppressing ITG-scale turbulence via a...
Mr
David Smith
(USA)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Validating predictive models of pedestal turbulence is critical for ITER and next-step devices. Here, we characterize the poloidal correlation length and decorrelation time of low-k pedestal turbulence in NSTX ELM-free, MHD-quiescent H-mode plasmas, plus we identify parametric dependencies that influence pedestal turbulence quantities. Poloidal correlation lengths in the pedestal are...
Mr
Yong-Su Na
(Republic of Korea)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
Since KSTAR has obtained the H-mode in 2010 campaign, H-mode plasmas were routinely obtained with combined heating of NBI with maximum power of 1.5MW and ECRH with maximum power of ~0.3 MW and ~0.6 MW for 110 GHz and 170 GHz, respectively. The L- to H-mode power threshold and confinement properties of KSTAR H-modes are investigatged in this work. Firstly, the L- to H-mode power threshold and...
Mr
Marc Beurskens
(UK)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
After the change-over from the Carbon-Fibre Composite (CFC) wall to an ITER-like metallic wall (ILW) the baseline type I ELMy H-mode scenario has been re-established in JET with the new plasma-facing materials Be and W. A key finding for ITER is that the power required to enter H-mode has reduced with respect to that in JET with the CFC wall. In JET with the ILW the power threshold to enter...
Mr
Shigeyuki Kubota
(USA)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
The measurement of radially extended meso-scale structures such as zonal flows and streamers, as well as the underlying microinstabilities driving them, is critical for under-standing turbulence-driven transport in plasma devices [1]. In particular, the shape and evolution of the radial wavenumber spectrum indicate details of the nonlinear spectral energy transfer [2], the spreading of...
Mr
Rory Scannell
(UK)
12/10/2012, 08:30
EXC - Magnetic Confinement Experiments: Confinement
Poster
The evolution of the MAST plasma during the L-H transition has been studied in the density range 1.5-3.0x10^19 m^-3. A dithering transition phase, the duration of which depends on the plasma density, is observed before the transition to ELMy or ELM free H-mode. A range of new diagnostic data has been taken during these periods, showing a spin-up of the perpendicular He+ flow correlated with...
Mr
Martin Kocan
(Germany)
12/10/2012, 08:30
EXD - Magnetic Confinement Experiments: Plasma–material interactions; divertors; limiters; scrape-off layer (SOL)
Poster
Latest research of intermittent transport in the scrape-off layer (SOL) of the ASDEX Upgrade tokamak is presented. Near the separatrix the fluctuations of the plasma and the floating potentials, measured by various Langmuir probes (LPs), are found to be anti-correlated due to fluctuations of the electron temperature. This indicates that, in contrast to a widely used experimental practice, a...
Mr
Jun Cheng
(China)
12/10/2012, 08:30
EXD - Magnetic Confinement Experiments: Plasma–material interactions; divertors; limiters; scrape-off layer (SOL)
Poster
A quasi-period electrostatic oscillation with 2-3 kHz is observed using Langmuir probe array during slow L-H transition in edge plasma of HL-2A Tokomak. This low frequency oscillation radially propagates inwards with 0.3-0.6 km/s inside the separatrix about 3-8 mm, and it appears on potential, density, electron pressure and Reynolds stress gradients. The dPe/dr fluctuation amplitude can reach...
Mr
Hans-Stephan Bosch
(Germany)
12/10/2012, 08:30
Poster
The “fully-optimized” stellarator Wendelstein 7-X stellarator, presently under construction in Greifswald, combines a quasi-isodynamic magnetic field configuration sustained by superconducting coils with a steady-state exhaust concept, steady-state heating at high power, and a size sufficient to reach reactor-relevant nT-values. It is the mission of the project to demonstrate the reactor...
Mr
Subrata Pradhan
(India)
12/10/2012, 08:30
Poster
Steady State Superconducting Tokamak (SST-1) commissioning attempted in 2006 was unsuccessful due to leaks being observed in magnet joints and isolators in the helium and nitrogen circuits. Additionally, 80 K thermal shields remained at higher temperature and leaks were observed in vacuum vessel baking channels. After a comprehensive review, the SST-1 refurbishment has been undertaken...
Mr
Hartmut Zohm
(Germany)
12/10/2012, 08:30
Poster
With ITER construction under way, the question of possible designs for a machine after ITER is receiving renewed attention. In many fusion energy roadmaps, such a step, often called DEMO, is a machine that should bridge the gap between ITER and the first commercial Fusion Power Plant (FPP). Hence, crucial elements for many DEMO designs are e.g. net electricity production or T-selfsufficiency...
Mr
Jonathan Menard
(USA)
12/10/2012, 08:30
Poster
A Fusion Nuclear Science Facility (FNSF) could play an important role in the development of fusion energy by providing the high neutron flux and fluence environment needed to develop fusion materials and components. The spherical tokamak (ST) is a leading candidate for an FNSF due to its compact size and modular configuration. Two activities preparing the ST for possible FNSF applications have...
Mr
David Ruzic
(USA)
12/10/2012, 08:30
Poster
As we come closer to realizing fusion as a viable power source, many machines which have made significant progress in plasma heating and power find that removing heat from the divertor region has become a challenging problem. Peak heat fluxes up to 20 MWm-2 are typical these days for machines and if there is an ELM event or disruption then it can be even higher. Solid plasma facing components...
Mr
Yuji Hatano
(Japan)
12/10/2012, 08:30
Poster
Tritium (T) inventory in tungsten (W) after neutron (n) irradiation is an important safety problem because radiation defects trap hydrogen isotopes. Therefore, deuterium (D) retention in n-irradiated W has been examined in Japan/US joint project TITAN. In this project, small W disks were irradiated in High Flux Isotope Reactor, Oak Ridge National Laboratory at coolant temperature (ca. 50...
Mr
Mark Gilbert
(UK)
12/10/2012, 08:30
Poster
The high-energy, high-intensity neutron fluxes produced by the fusion plasma will have a significant life-limiting impact on reactor components in both experimental and commercial fusion devices. Not only do the neutrons bombarding the materials induce atomic displacement cascades, leading to the accumulation of structural defects, but they also initiate nuclear reactions, which cause...
Mr
Hiroo Kondo
(Japan)
12/10/2012, 08:30
Poster
Construction and initial performance tests of EVEDA (Engineering Validation and Engineering Design Activities) Lithium Test Loop (ELTL) were completed and therefore one of the major milestones in the engineering validation toward IFMIF (International Fusion Materials Irradiation Facility) was accomplished. The ELTL, which holds 2.5-ton Li, is a proto-type of a Li target facility of the IFMIF...
Mr
Ellappan Rajendrakumar
(India)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
The development of Lead-Lithium Ceramic Breeder (LLCB) blanket is being performed as the primary candidate of Indian Test Blanket Module (TBM) program towards DEMO reactor. The LLCB TBM will be tested from the first phase of ITER operation (H-H phase) in one-half of a ITER port no-2. Neutronic calculations for the above design of LLCB TBM blanket have been carried out to estimate tritium...
Mr
Giacomo Aiello
(France)
12/10/2012, 08:30
ITR - ITER Activities
Poster
This paper gives an overview of the activities carried out at CEA concerning different aspects of the module and the associated systems (TBS – Test Blanket System): system engineering and configuration management, compliance with existing regulation, conceptual design, manufacturing and assembling of subcomponents, testing programme, instrumentation needs, ancillary systems, maintenance in...
Mr
Kaiming Feng
(China)
12/10/2012, 08:30
ITR - ITER Activities
Poster
The helium-cooled/solid breeder with the pebble bed concept has been adopted in Chinese ITER test blanket modules (TBM) design. The structure dimension of HCCB TBM design is based on 1/2 ITER test port divided vertically. In order to reduce the effects of magnetic field ripple, the design was updated with reduced RAFM steel mass. The arrangement of pebble beds in the sub-module is changed from...
Mr
Jan Fikar
(Switzerland)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
In order to increase the operation temperature of the high-chromium reduced activation steels foreseen in applications of fusion reactors, ferritic steels containing 12 to 14% Cr in weight and reinforced with a dispersion of nano-oxides are being under development. The nano-oxides are incorporated into the matrix by adding Y2O3 or Fe-Y intermetallic particles to the initial steel powder, and...
Mr
Viacheslav Chernov
(Russian Federation)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
The Results of development and researches of functional properties of low activation vanadium alloys (V-Ti-Cr and V-Cr-W-Zr-C systems) being developed for the cores of nuclear fusion and fission (Gen-IV, space) power reactors are presented.
Scientific and technological problems of the investigations are related with enhancement of functional properties based on (1) special optimized thermal...
Mr
Englen Azizov
(Russian Federation)
12/10/2012, 08:30
Poster
Development of tokamak based fusion neutron sources and fusion-fission hybrids for nuclear fuel production and nuclear waste transmutation has been initiated in Russia to accelerate implementation of modern magnetic fusion technologies.
Various devices realizing intense DT fusion from 1 MW up to 100 MW have been considered and passed the pre-conceptual design level. Those include conventional,...
Mr
Terry Kammash
(USA)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
A Comprehensive analysis of the feasibility of a fusion hybrid reactor whose fusion component is the gasdynamic mirror (GDM) is presented. Since the primary role of the fusion component is to supply neutrons to a blanket laden with fertile material, it can operate at or near “breakeven” condition which is a much less stringent condition than that required for a pure fusion reactor. As a high...
Mr
Thomas Simonen
(USA)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Fusion Development will require materials capable of withstanding extensive harsh bombardment by energetic neutrons and plasma. The plasma based Gas Dynamic Trap neutron source concept is capable of testing and qualifying materials and fusion blanket sub modules for eventual deployment in fusion energy systems. In this paper we describe new results on the suitability of this source to assess...
Mr
Myung Hyun Kim
(Republic of Korea)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
In this paper, a design concept of fusion-fission hybrid reactor for the purpose of high level radioactive waste transmutation was investigated. A concept of fusion based trans-uranium isotope (TRU) burner reactor (FTBR) was based on a low power tokamak (150 MW max) and annular ring shaped TRU core with metallic fuel (TRU 60 w/o, Zr 40 w/o) and adjacent fission product (FP) zone. Composition...
Mr
Hacı Şahin
(Turkey)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
A fusion–fission (hybrid) is a combination of the fusion and fission processes. The fusion plasma is surrounded with a multi-layered cylindrical blanket made of the fertile materials (238U or 232Th) to convert them into fissile materials (239Pu or 233U) by transmutation through the capture of the high-yield fusion neutrons and neutron multiplier and coolant zone made of LiPb. A hybrid reactor...
Mr
Zhiwei Zhou
(China)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
In this paper, a thorium-uranium based fusion-fission hybrid reactor (FFHR) aiming at efficiently utilizing natural uranium and thorium resources is presented. The major objective is to study the feasibility of this new concept with multi-purposes, including energy gain，tritium breeding ratio (TBR) and 233U breeding rate. The basic logic of this concept is to use the excess neutrons generated...
Mr
Boris Kuteev
(Russian Federation)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Development of the demonstration fusion neutron source FNS-ST for the nuclear fuel production and the nuclear waste transmutation on the basis of a spherical tokamak with the MW power of deuterium and tritium fusion has reached the stage of technical requirements for conceptual design.
The concept of a FNS-ST has been proposed and developed in details (plasma current 1.5 MA, magnetic field...
Mr
Mike Kotschenreuther
(USA)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Fusion Fission Hybrids present a much less technically demanding, nearer term, application of fusion research. Pre-conceptual designs of Fission-Fusion Hybrids are based on conventional tokamaks and spherical tokamaks are presented and compared. The designs have multiple unique features, relative to other hybrid approaches. The worst of nuclear accidents- the criticality accidents – are...
Mr
Tomoaki Hino
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
It is quite important to investigate the performance of glow discharge conditionings for controls of in-vessel tritium inventory and hydrogen recycling. For this purpose, first, the deuterium retentions in tungsten (W), graphite (C) and stainless steel (SS) were measured. The retention in W was not small as expected, several times larger than that of SS, although the retention in SS was one...
Mr
Minh Quang Tran
(Switzerland)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Due to the superior thermophysical properties, tungsten (W) materials are candidates for plasma facing applications for ITER and DEMO. W-base materials are being developed on the basic idea that alloys and nano-grained materials should be more ductile than pure W and standard grain-sized materials, and that oxide or carbide dispersion strengthened materials should be more radiation resistant...
Mr
Valery Borovikov
(USA)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Radiation damage by fusion neutrons can significantly degrade material properties. In a fusion reactor, long-lasting radiation-induced defects such as vacancies, vacancy clusters, and voids introduce additional nuclear safety complication in terms of trap ites for excessive tritium retention. This is especially true in the divertor/first wall of a tokamak like ITER, where extreme thermal...
Mr
Takeo Muroga
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
The research in Japan-USA fusion cooperation program TITAN (Tritium, Irradiation, and Thermofluid for America and Nippon, from April 2007 to March 2013) is highlighted by tritium transfer in PFM exposed to tritium-plasma, effects of neutron irradiation on deuterium retention in PFM, MHD flow of Li-Pb in magnetic fields, synergistic neutron irradiation and helium injection effects for...
Mr
Eiichi Wakai
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Recent progress of small specimen test technique (SSTT) for the IFMIF (International Fusion Materials Irradiation Facility) test cell is mainly evaluated in this paper. The engineering designs and validations of high flux test module (HFTM) are performed by JAEA, Japanese Universities, and Karlsruhe Institute of Technology (KIT) in the IFMIF/EVEDA (Engineering validation and engineering design...
Mr
Jiming Chen
(China)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Development of low activation structural materials is a critical path to fusion power plant. This paper briefly reviews the strategies for structural materials development in Southwestern Institute of Physics (SWIP) and the current status of the materials under investigation.
To provide material database for the China Helium-cooled ceramic breeder TBM, several 1000kg heats of CLF-1 RAFM...
Mr
Hiroyasu Tanigawa
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Crucial issues on the path to fusion power are the development of plasma facing and breeding blanket materials which are capable of withstanding high neutron fluences and high heat fluxes. Reduced activation ferritic/martensitic (RAFM) steels are now considered to be the candidates for structural applications in the fusion demonstration reactor, DEMO, because they have a sound engineering...
Mr
Troyo Troev
(Bulgaria)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Simulations of damages in beryllium, alpha-iron and tungsten, irradiated by fusion neutrons have been performed using molecular dynamics (MD). We applied three codes MCNP5, GEANT4 and FLUKA for simulation of 14 MeV neutron interactions in beryllium, iron and tungsten lattices. The displacement cascades induced by the Primary Knocked-on Atoms (PKA), produced by the bombardment of fast neutrons...
Mr
Ulrich Fischer
(Germany)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
The availability of suitable computational methods, tools, models and data, qualified for design applications, is a pre-requisite to enable reliable nuclear design and performance analyses of future fusion devices. Various efforts are being conducted worldwide to develop and extend the capabilities of the neutronics simulation tools including the capabilities to model the problem geometry in...
Mr
Akira SAKASAI
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
The JT-60SA vacuum vessel (VV) and divertor are key components for the performance requirements. Therefore the manufacturing and development of VV and divertor are in progress by the first priority, inclusive of the superconducting magnets. The vacuum vessel has a double wall structure in high rigidity to withstand electromagnetic force at disruption and to keep high toroidal one-turn...
Mr
Srinivasan PANCHAPAKESAN
(India)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
DD/DT reaction neutron generators are used as sources of 2.5 MeV/14 MeV neutrons in laboratories for various purposes. 14 MeV neutron generators are proposed to be located at several positions in the ITER vessel for calibrating neutron/gamma diagnostic systems. Detailed knowledge of the radiation dose rates around the neutron generators is essential to obtain data on personnel exposures,...
Mr
Shunsuke Ide
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Assessment of plasma operation scenarios and possible operation spaces in JT-60SA has been carried out with emphasis on controllability with actuators, including not only heating and current drive but also fueling and pumping system. The main target of this assessment is high normalized pressure (beta_N) steady-state scenario, which requires careful control. It is confirmed that the safety...
Mr
Aashoo Sharma
(India)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Steady State Superconducting (SST-1) Magnet system comprises of sixteen superconducting Toroidal Field (TF) Magnets, nine superconducting Poloidal Field (PF) Magnets, resistive central solenoid (CS) and compensating magnets, resistive Vertical Field (VF) equilibrium magnets, resistive in-vessel feedback coils and radial control coils. The magnet system could only be partially commissioned in...
Mr
Carlos Eduardo Velasquez
(Brazil)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Three different models of Power Plant Conceptual Study (PPCS) are considered maintaining some conditions as the volume of the vacuum chamber (VC) based on the ITER parameters, in order to study the effect of the neutron flux related to the shape of each VC. Using MCNP, three surfaces were simulated: plane, cylindrical and torus. One of the geometries is made considering the intersection of...
Mr
Mikhail Gryaznevich
(UK)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
It has long been known that high temperature superconductors (HTS) could have an important role to play in the future of tokamak fusion research. Here we report on first results of the use of HTS in a tokamak magnet and on the progress in design and construction of the first fully-HTS tokamak. In the experiment, the two copper vertical field coils of the small tokamak GOLEM were replaced by...
Mr
Eugenijus Uspuras
(Lithuania)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Fusion is the energy production technology, which could potentially solve problems with growing energy demand of population in the future. Starting 2007, Lithuanian energy institute (LEI) is a member of European Fusion Development Agreement (EFDA) organization. LEI is cooperating with Max Planck Institute for Plasma Physics (IPP, Germany) in the frames of EFDA project by performing safety...
Mr
Thomas Brown
(USA)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Abstract - A fusion pilot plant study was initiated to clarify the development needs in moving from ITER to a first of a kind fusion power plant, following a path similar to the approach adopted for the commercialization of fission. The mission of the pilot plant was set to encompass component test and fusion nuclear science missions yet produce net electricity with high availability in a...
Mr
Richard Kemp
(UK)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Recent systems studies work within the Broader Approach framework has focussed on bench-marking the EU systems code PROCESS against the Japanese code TPC for conceptual DEMO designs. This paper describes benchmarking work for a onservative, pulsed DEMO and an advanced, steady-state, high-bootstrap fraction DEMO. The resulting former machine is an R_0 = 10 m, a = 2.5 m, beta_N < 2.0 device with...
Mr
Francesco Paolo Orsitto
(Italy)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
The present report deals with a Review of problems for a Steady state(SS) DEMO, related argument is treated about the models and the present status of comparison between the characteristics of DEMO pulsed versus a Steady state device.The studied SS DEMO Models ( SLIM CS , PPCS model C EU-DEMO, ARIES-RS) are analyzed from the point of view of the similarity scaling laws and critical issues for...
Mr
Hiroyasu Utoh
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Maintenance is a critical issue for fusion DEMO reactor because the design conditions and requirements of DEMO maintenance scheme are different from that of ITER remote handling. The sector transport maintenance scheme has advantages to maintain blankets and divertors without the use of sophisticated remote handling devices including sensitive devices to radiation in the reactor. SlimCS...
Mr
Nobuyuki Asakura
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Power exhaust scenario for a 3 GW class fusion reactor with the ITER-size plasma has been developed with enhancing the radiation loss from seeding impurity. Transport of plasma, impurity and neutrals was simulated self-consistently, for the first time, under the Demo divertor condition using an integrated divertor simulation code SONIC. The total heat load, q_target, was evaluated including...
Mr
Youji Someya
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
JAEA has conducted the conceptual design study of blanket for a fusion DEMO reactor SlimCS. Considering DEMO specific requirements, we place emphasis on a blanket concept with durability to severe irradiation, ease of fabrication for mass production, operation temperature of blanket materials, and maintainability using remote handling equipment. This paper present a promising concept...
Mr
Junichi Miyazawa
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Theoretical analyses on the MHD equilibrium, the neoclassical transport, and the alpha particle transport, etc., are being carried out for a helical fusion DEMO reactor named FFHR-d1, using radial profiles extrapolated from LHD. FFHR-d1 is a heliotron type DEMO reactor of which the conceptual design activity has been launched since 2010. It is possible to sustain the burning plasma without...
Mr
Andrea M. Garofalo
(USA)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
A Fusion Nuclear Science Facility based on the Advanced Tokamak concept (FNSF-AT) [1] is a key element of a fast track plan to a commercially attractive fusion DEMO. The next step forward on the path towards fusion commercialization must be a device that complements ITER in addressing the community identified science and technology gaps to DEMO, and that enables a DEMO construction decision...
Mr
Teruya Tanaka
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
Neutronics design study has been performed in a newly started conceptual design activity for a helical type DEMO reactor FFHR-d1. Features of the FFHR-d1 design are enlargement of the basic configurations of reactor components and extrapolation of plasma parameters from those of the helical type plasma experimental machine Large Helical Device (LHD) to achieve the highest feasibility. From the...
Mr
Nagato Yanagi
(Japan)
12/10/2012, 08:30
FTP - Fusion Technology and Power Plant Design
Poster
The conceptual design studies of the LHD-type helical fusion DEMO reactor, FFHR-d1, are progressing steadfastly. The LHD-type heliotron magnetic configuration equipped with the built-in helical divertors has a potential to realize low divertor heat flux in spatial average. However, the toroidal asymmetry may give more than a couple of times higher peak heat flux at some locations, as has been...
Mr
George Neilson
(USA)
12/10/2012, 08:30
SEE - Safety, Environmental and Economic Aspects of Fusion
Poster
Nations engaged in magnetic fusion R&D are now examining the needed programmes to move toward DEMO, i.e., a practical demonstration of electricity generation on a power plant scale, also satisfying a range of socio-economic goals. The path to DEMO will include major fusion nuclear facilities and their accompanying programmes to develop the various technologies needed to harness fusion energy...
Mr
Hansoo CHANG
(Republic of Korea)
12/10/2012, 08:30
SEE - Safety, Environmental and Economic Aspects of Fusion
Poster
Until the Fukushima disaster of March 2011, the recent history of nuclear power has been relatively uneventful. About 440 power reactors in 30 countries have been operating for almost 25 years without a catastrophic accident, and this relative uneventfulness and encouraging safety record led many to believe in the viability of a large-scale global nuclear expansion or renaissance....
Mr
Kozo Yamazaki
(Japan)
12/10/2012, 08:30
SEE - Safety, Environmental and Economic Aspects of Fusion
Poster
Global warming due to rapid greenhouse gas (GHG) emission is a serious environmental problem, and fusion reactors are expected as one of safe and abundant electric power generation systems to reduce GHG emission amounts. To search for economic, environment-friendly and energy-efficient fusion reactors, system studies have been done using PEC (Physics-Engineering- Cost) code taking care of...
Mr
Colin Roach
(UK)
12/10/2012, 08:30
Poster
Plasma equilibria reconstructed from the spherical tokamak MAST, have sufficient resolution to capture plasma evolution during the short period between edge-localised-modes (ELMs). Immediately after the ELM steep gradients in pressure, P, and density, n_e, form a pedestal close to the separatrix, and then expand into the core. Local gyrokinetic analysis over the ELM cycle reveals the dominant...
Mr
Tianyang Xia
(China)
12/10/2012, 08:30
THD - Magnetic Confinement Theory and Modelling: Plasma–material interactions; divertors, limiters, scrape-off layer (SOL)
Poster
In this paper we report the simulations on ELMs with 5-field peeling-ballooning model using BOUT++ code. A minimum set of three-field two-fluid equations based on the peeling-ballooning (P-B) model with non-ideal physics effects is found to simulate pedestal collapse when using the BOUT++ simulation code [PRL, Vol 105, 175005 (2010)]. Based on this 3-field model, we investigate the effects of...
Mr
Xueqiao Xu
(Lawrence Livermore National Laboratory)
12/10/2012, 08:30
THD - Magnetic Confinement Theory and Modelling: Plasma–material interactions; divertors, limiters, scrape-off layer (SOL)
Poster
This paper reports the theoretical and simulation results of a gyro-Landau-fluid (GLF) extension of the BOUT++ code which contributes to increasing the physics understanding of edge-localized-modes (ELMs). Large ELMs with low-to-intermediate-n peeling-ballooning (P-B) modes are significantly suppressed due to finite Larmor radius (FLR) effects when the ion temperature increases. However, small...
Mr
Nobuhiko Hayashi
(Japan)
12/10/2012, 08:30
Poster
The reduction of ELM energy loss by the pellet injection for ELM pacing has been studied by an integrated core / scrape-off-layer / divertor transport code TOPICS-IB with a MHD stability code and a pellet model. In the ELM pacing, ELMs with the reduced energy loss should be reliably triggered by small pellets to minimize fueling and the impact on the target pedestal plasma. It is found that...
Mr
Walter Guttenfelder
(USA)
12/10/2012, 08:30
Poster
Nonlinear simulations have progressed for multiple NSTX discharge scenarios to (i) validate with experimental turbulence and transport data, (ii) help differentiate unique instability mechanisms, and (iii) improve confidence in predictive modeling for future low aspect ratio fusion devices. First nonlinear gyrokinetic simulations of microtearing turbulence in a high-beta NSTX H-mode discharge...
Mr
Hogun Jhang
(Republic of Korea)
12/10/2012, 08:30
Poster
We study the coupling of intrinsic rotation and toroidal momentum transport to the dynamics of internal transport barriers (ITB). In particular, we (1) elucidate the role of external torque in ITB formation and ion temperature de-stiffening, (2) analyze the interplay between intrinsic rotation and ITB dynamics, and (3) characterize the heat transport in steady state ITB plasmas. First, we find...
Mr
Evgeniy Gusakov
(Russian Federation)
12/10/2012, 08:30
Poster
The complex interaction between large-scale mean flows, meso-scale zonal flows and fine-scale micro-turbulence excited due to specific profiles of plasma parameters and leading to anomalous transport is an important area of experimental and theoretical research in magnetically confined plasmas. Recent progress in massively parallelized simulations of the electron and ion gyrokinetic particle...
Mr
Frank Jenko
(Germany)
12/10/2012, 08:30
Poster
One of the key challenges for plasma theory and simulation in view of ITER is to enhance the understanding and predictive capability concerning high-performance discharges. The goal of this contribution is to shed light on central open issues by means of physically comprehensive ab initio simulations with the global gyrokinetic code GENE (including electromagnetic effects, collisions, and real...
Mr
Par Strand
(Sweden)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
In the present work the turbulent transport of main ions and impurities in tokamaks, driven by ion scale ITG/TE modes and electron scale ETG modes, is studied. Nonlinear and quasi-linear gyrokinetic simulation results obtained with the code GENE are compared with results from a computationally efficient fluid model. In particular, the transport of particles in regions of steep density...
Mr
Yusuke Kosuga
(USA)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
Predictive modelling of turbulent transport is essential to the success of ITER and DEMO. Since first principle simulations cannot yet confront the complexities of this task, some model reduction is necessary, both for utility and for understanding. Two critical issues in transport model design are: a.) the structure of mean field theory for Kubo number larger than or order of unity, b.) the...
Mr
Ihor Holod
(USA)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
Recent progress in gyrokinetic simulations of plasma microturbulence using GTC code is reported. Several topics are covered, including anomalous transport of toroidal angular momentum, simulations in real geometry, validation and verification efforts, and extension of the simulation model to include the magnetic field perturbations.
Simulations of momentum transport driven by the ion...
Mr
Johan Anderson
(USA)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
There has been overwhelming evidence that coherent structures such as vortices, streamers and zonal flows (m = n = 0, where m and n are the poloidal and toroidal modenumbers respectively) play a critical role in determining the overall transport in magnetically confined plasmas [1]. Some of these coherent structures, so called streamers, are radially elongated structures that cause...
Mr
J. Salomon Janhunen
(Aalto University School of Science)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
One of the outstanding problems of transport processes in tokamaks is the L-H transition and in general transport barrier formation, explanation of which has attracted several possible hypotheses ranging from purely neo-classical (rotational runaway) to parametric instabilities between turbulent eddies and zonal flows. Total f gyrokinetic simulation allows for the investigation of all the most...
Mr
Jian-Zhou Zhu
(China)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
Nonlinear gyrokinetic equations play a fundamental role in our understanding of fusion plasma turbulence and associated transport. Gyrokinetics can be Galerkin truncated to have the absolute statistical equilibrium solution to which the truncated system should ultimately relaxed and be used to study the turbulence and the relevant transports. Here, we systematically review several versions of...
Mr
Motoki Nakata
(Japan)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
The plasma size (rho*) and collisionality (nu*) scaling of toroidal ion temperature gradient driven turbulent transport is investigated by using a full-f global gyrokinetic code GT5D with fixed gradient (FG) and fixed source (FS) models. The FG model with an adaptive source/sink, which sustains a zero-toroidal-rotation and a constant temperature profile, is newly introduced so as to emulate...
Mr
Paul Terry
(USA)
12/10/2012, 08:30
THW - Magnetic Confinement Theory and Modelling: Wave–plasma interactions; current drive; heating; energetic particles
Poster
The regulation of ion temperature gradient (ITG) turbulence by zonal flows, which reduces turbulence levels and transport, is shown to involve enhanced energy transfer from the insta-bil¬ity to damped modes in the low wavenumber range of the instability, with zonal flows acting as a catalyst. Energy transfer is dominated by the nonlinear triplet interaction of the unstable mode, a zonal flow,...
Mr
Yanick SARAZIN
(France)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
Any means towards turbulence control would be highly beneficial to fusion reactors. Experimentally, fusion plasmas can exhibit spontaneous transitions towards high confinement regimes characterized by local reduction of turbulent transport. The resulting transport barriers exhibit complex dynamics: they can expand and/or move adiabatically, but they can also experience sudden relaxations,...
Mr
Klaus Hallatschek
(Germany)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
It is extremely appealing to externally excite geodesic acoustic modes in a tokamak, either to artificially reduce the turbulent transport provided sufficiently large amplitude is achievable, since GAMs are theoretically expected to impact the transport, or for diagnostic purposes, since the GAM frequency is dependent on the temperature and flux surface shapes. Moreover, even when not...
Mr
Chang-Bae Kim
(Republic of Korea)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
Appearance of advective flux in the turbulent plasmas driven by noise is studied numerically. The noise is assumed to be delta-correlated in time and to have anisotropic component so that a reflection symmetry is not obeyed along y direction. Numerical simulations are performed for a two-dimensional model of Hasegawa-Mima equation (HME). It is found that, under uv forcing, the induced flux...
Mr
Taik Soo Hahm
(Republic of Korea)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
KSTAR tokamak has achieved H-mode plasmas well ahead of its original schedule [1]. An interesting feature of KSTAR plasmas at the H-mode transition is an abrupt increase in its edge q value [2]. Often, this happens as the plasma becomes diverted, losing a contact with the outer limiter. Motivated by the KSTAR results, we investigate how plasma boundary shape such as x-point modifies the ExB...
Mr
Seung-Hoe Ku
(USA)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
A first principles-based understanding of the relationship between the ion temperature (Ti) at the pedestal top and that in the central core is critically needed to enable reliable predictions of fusion power efficiency in ITER. Utilizing petascale high-performance computers, the multi-scale (combined neoclassical, kinetic turbulence, and neutral physics scales), full-function (“full-f”)...
Mr
Wei Xing Wang
(USA)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
New results obtained from global gyrokinetic simulations regarding turbulence-induced plasma current and flow shear driven turbulence and transport in tokamaks are reported in this paper. i) These plasma self-generated non-inductive parallel currents can have a strong impact on the physics of plasma disruptions and overall plasma confinement. Specifically, their influence on key...
Mr
Rajaraman Ganesh
(India)
12/10/2012, 08:30
THC - Magnetic Confinement Theory and Modelling: Confinement
Poster
The use of a generalized weight-based particle simulation scheme suitable for simulating Tokamak plasmas, where the zeroth-order inhomeneity is important is presented. The scheme which is a genaralization of the perturbation schemes developed earlier for particle-in-cell (PIC) simulations, is now capable of handling the full distribution of particles. The new scheme can simulate both the...
