Dr
Guosheng Xu
(Institute of Plasma Physics, Chinese Academy of Sciences)
23/10/2018, 14:00
Poster
A highly reproducible stationary grassy ELM regime has been achieved in the EAST superconducting tokamak with water-cooled metal wall, exhibiting good energy confinement, H_98y2~1.1, strong tungsten impurity exhaust, and compatibility with low rotation, high density and fully non-inductive operations. It offers thus a highly promising operational regime in EAST, potentially applicable to...
Dr
Prashant Sharma
(ITER-India, IPR Gandhinagar)
23/10/2018, 14:00
Poster
Tungsten is a promising candidate for first-wall material in fusion reactors and its use as a plasma-facing material is being investigated in both tokamaks as well as laboratory experiments [1, 2]. In fusion environment tungsten will be exposed to neutron, helium and hydrogen isotope implantation along with the heat flux which will lead to material damage. Irradiation by charged particles such...
Dr
Jonathan Graves
(Ecole Polytechnique Federale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland)
23/10/2018, 14:00
Poster
The VENUS-LEVIS code [D. Pfefferle, *et al*, Compt. Phys. Communs. **185**, 3127 (2014)] has been optimised for full orbit and guiding centre simulations in fully 3D electromagnetic fields. Curvilinear flux coordinate systems are deployed, with analytic (Fourier) representation of the fields for accurate simulation over slowing down time scales of fast particles and heavy impurities. An...
Dr
Liang Wang
(Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP))
23/10/2018, 14:00
Poster
Managing excessively high divertor power and particle fluxes and related plasma-wall interactions (PWI) is one of the most critical issues for the steady-state operation of the EAST superconducting tokamak and future fusion devices, such as ITER and CFETR. A world record long pulse H-mode operation of 101.2 seconds with H_98=1.1 and total power injection of 0.3 GJ has been successfully...
Dr
Yawei Hou
(University of Science and Technology of China)
23/10/2018, 14:00
Poster
For burning plasmas in fusion reactors, Energetic Particles (EP) generated from plasma heating and D-T reaction can destabilize Alfven Eigenmodes (AE). Alfven eigenmodes can conversely induce transport and loss of energetic particles. It is one of the crucial issues to study the interaction between EPs and AEs for CFETR (China Fusion Engineering Test Reactor). Eigenanalysis of AEs in CFETR...
Mr
Udaya Maurya
(InIPR)
23/10/2018, 14:00
Poster
To achieve self-sustained ignited operation in a high energy Tokamak, it is important to understand and maximize the energy confinement time, which falls in the domain of transport theory. To analyze and understand dynamics of plasma in Tokamak, performing a one-dimensional transport simulation is still one of the best approaches. In our work we focus on burning plasma simulation and study the...
Dr
JYOTIRMOY PRAMANIK
(DEPT OF PHYSICS, KHARAGPUR COLLEGE)
23/10/2018, 14:00
Poster
Most of the tokamaks including ITER, a significant part of the plasma-facing component including diverters, limiters, etc is comprised with graphite material. In the fusion plasma environment, the graphite gets bombarded by hydrogen and its isotope (deuterium and tritium) ions and erode graphite to a significant extent. Since such carbon particles can retain large amounts of hydrogen, dust...
Gregorio Vlad
(ENEA, Fusion and Nuclear Safety Department, Frascati, Italy)
23/10/2018, 14:00
Poster
The results of a set of simulations of Alfvén modes driven by an energetic particle population are presented, with the specific aim of comparing energetic particle radial transport between single-n and multiple-n simulations. The hybrid reduced O($\epsilon^3_0$) MHD gyrokinetic code HMGC is used, retaining both fluid (wave-wave) and energetic particles nonlinearities. The code HMGC retains...
Dr
RYOSUKE SEKI
(National Institute for Fusion Science)
23/10/2018, 14:00
Poster
In the LHD, the fast ion confinement has been investigated by using three tangentially injected neutral beams (NBs) with 180 keV fast ions and/or two perpendicularly injected NBs with 40-80 keV fast ions. The Alfvén eigenmodes (AEs) are observed during the tangential-NB injections. The fast ion driven instabilities enhance the fast ion losses. It is important to identify the instabilities and...
Mr
Shrishail Padasalagi
(ITER-India, IPR, HBNI)
23/10/2018, 14:00
Poster
The ECE diagnostic is planned to be used for the measurements of plasma electron temperature profile with good spatial and temporal resolutions. Secondary objectives are to obtain information on non-thermal electron populations and the power loss due to ECE.
One of the major requirements of ITER like Fusion Device is to study the plasma parameter to ascertain and control the fusion...
Dr
Defeng Kong
(Institute of Plasma Physics Chinese Academy of Sciences)
23/10/2018, 14:00
Poster
A non-stationary, effective edge localized modes (ELMs) mitigation / suppression regime has been recently obtained by counter NBI heating at high collisionality on the Experimental Advanced Superconducting Tokamak (EAST). Our results show that counter NBI can significantly enhance the reversed toroidal rotation as well as the E_r×B flow shear of the pedestal. With the increased E_r×B flow...
Mr
Montu Bhuva
(Institute for Plasma Research, INDIA)
23/10/2018, 14:00
Poster
A direct current (dc) plasma source consisting of hollow cathode geometry and a constricted anode is presented. The effect of a hollow cathode geometry on radial density distribution of a magnetized plasma column has been studied in a low-pressure (approximately 1.4Pa) argon discharge. The plasma column is characterized using Langmuir probe and the radial density distribution for two different...
Mr
Umesh Kumar
(Institute for Plasma Research, Gandhinagar, Gujarat, India)
23/10/2018, 14:00
Poster
A simple toroidal device (SMT) is a toroidal device in which plasma is
confined by the application of toroidal and vertical magnetic field only
resulting in absence of a conventional effective rotational transform. Such
devices provide a simple and well diagnosable test-bed for studies related
to equilibrium, fluctuations and particle confinement for Tokamak edge.
The device BETA at the...
Dr
Pengjun Sun
(Institute of Plasma Physics, Chinese Academy of Sciences)
23/10/2018, 14:00
Poster
Understanding plasma transport in phases with significant MHD activities (especially during plasma current ramp-up/down and disruption) in tokamak plasmas is crucial for predicting and thus controlling plasma behavior for future fusion devices, e.g. ITER. Since microturbulence plays an important role in driving anomalous plasma transport, the interactions between MHD modes and microturbulence...
Ms
Juan Huang
(CnIPPCAS)
23/10/2018, 14:00
Poster
On the EAST tokamak, one hundred seconds steady state H-mode (H98y2~1.1) discharge has been achieved by RF-only (LHW+ECRH+ICRH) heating with improvement of the auxiliary heating and current drive systems on actively cooled ITER-like mono-block tungsten divertor. Towards EAST high performance advanced state-steady operation regimes, fast-ion related physical issues become crucial for achieving...
Dr
Ralf Kleiber
(Max-Planck-Institut für Plasmaphysik)
23/10/2018, 14:00
Poster
Results from a hybrid approach (CKA-EUTERPE code) which couples an MHD code
with a gyrokinetic code are presented. Although perturbative, it offers a
relatively fast way to investigate the destabilisation of Alfven modes by
fast particles. TAE saturation amplitudes and their scaling with growth rate
and collisionality were investigated in a tokamak as well as in Wendelstein
7-X.
Full...
Dr
Manoj Kumar
(Institute for Plasma Research)
23/10/2018, 14:00
Poster
Plasma imaging is an essential diagnostics system for any tokamak as it can provide vital information on various plasma parameters. These systems are ones of the first diagnostics installed and are basic not only at start-up stage but also in subsequent operations. Imaging system generally consists of at least two cameras, one of them is a high speed camera and another one is slow speed...
Mr
Prabhakar Srivastav
(Institute For Plasma Research, Bhat Gandhinagar India-382428)
23/10/2018, 14:00
Poster
Extensive measurements are carried out on micro turbulence because of their possible role in causing anomalous particle and energy transport in fusion devices [1]. Outcome from past investigations suggest that the Electron Temperature Gradient (ETG) driven turbulence is considered presently as a major source of anomalous plasma transport in fusion devices, as transport by ion scale turbulence...
Dr
Liqing Xu
23/10/2018, 14:00
EXW - Magnetic Confinement Experiments: Wave–plasma interactions; current drive; heating; energetic particles
Poster
Two types of kink modes, fishbone and long-lived mode are experimentally and numerically studied at EAST tokamak. In high β_{P} plasma, sawtooth instability was replaced by a saturated 1/1 internal kink mode which either manifests itself as a periodical burst energetic ion related fishbone or as a long-lived mode which is associated to the core safety factor at q_0~1. The present of those 1/1...
Ms
Meenakshee Sharma
(Institute for Plasma Research)
23/10/2018, 14:00
Poster
The cusp configuration reduces the plasma losses to boundary by diverging plasma to the narrow regions where the magnetic field lines intersect the wall. The efficiency of multi dipole cusp confinement depends on the plasma losses through cusp loss area, widely known as leak width. The Multi-line cusp Plasma Device (MPD) used electromagnets for plasma confinement and gives opportunity to vary...
Prof.
Didier Moreau
(CEA/DSM/IRFM)
23/10/2018, 14:00
Poster
Robust model-predictive control (MPC) algorithms based on extremely simple linear data-driven models have been recently developed for plasma kinetic control on EAST. This paper shows, for the first time, that MPC can be performed using a two-time-scale approximation, considering the kinetic plasma dynamics as a singular perturbation of a quasi-static magnetic equilibrium, which itself is...
Mrs
Himabindu Manthena
(IPR)
23/10/2018, 14:00
Poster
To solve the challenging problem of heat removal in a tokamak based fusion reactor, several advanced divertor configurations have been proposed and studied. We present here the reults of our studies of one of the more promising configurations, the X-divertor, conducted for the parameters of the Indian tokamak SST-1. Using the equilibrium code CORSICA, we develop the appropropraite magnetic...
Dr
Zhiyong Qiu
(Zhejiang University)
23/10/2018, 14:00
Poster
Gyrokinetic theory of nonlinear mode coupling as a mechanism for toroidal Alfv\'en eigenmode (TAE) saturation and thermal plasma heating in the fusion plasma related parameter regime is presented, including 1) parametric decay of TAE into lower kinetic TAE (LKTAE) and geodesic acoustic mode (GAM), and 2) enhanced TAE coupling to shear Alfv\'en wave (SAW) continuum via ion induced scattering....
Dr
Elena Belova
(PPPL)
23/10/2018, 14:00
Poster
Simulations of confinement-limiting Alfvén eigenmodes in the sub-cyclotron frequency range show a robust physical stabilizing mechanism via modest off-axis beam injection, in agreement with experimental observations from National Spherical Torus Experiment (NSTX-U). Experimental results from NSTX-U have demonstrated that neutral beam injection from the new beam sources with large tangency...
Mr
Chinmoy Mallick
(institute for Plasma Research)
23/10/2018, 14:00
Poster
Microwave discharge ion source (MDIS) is used in many applications including accelerators based neutron generators on suitable target through D_D or D_T fusion. The electromagnetic (EM) pump wave (ω_0) can propagate beyond cut off plasma density by changing its polarity and/or decomposing into different daughter waves through which it transfer its energy thus producing over dense plasma. Role...
Mr
DHARMENDRA RATHI
(INSTITUTE FOR PLASMA RESEARCH)
23/10/2018, 14:00
Poster
Proper wall conditioning has turned out to be an essential element for achieving the highest possible plasma performance in present-day fusion devices. The main issues are controlling the generation of plasma impurities, liberated by plasma-surface interactions. Superconducting fusion machines need efficient wall conditioning techniques for routine operation in between shots in the presence of...
Dr
Annika Ekedahl
(CEA, IRFM)
23/10/2018, 14:00
Poster
Recent long pulse experiments in EAST have resulted in a new world record of 100 s long H-mode discharge, sustained by the radiofrequency (RF) systems, predominantly Lower Hybrid Current Drive (LHCD). In parallel, experiments in HL-2A have demonstrated successful LH wave coupling in H-mode plasmas with an ITER-relevant passive-active multijunction (PAM) LHCD launcher. These two achievements,...
Mr
Satadal Das
(Institute For Plasma Research)
23/10/2018, 14:00
Poster
The cross-field transport of electrons/ions across magnetic field is fundamentally important as it determinines the characteristics of plasma wetted area in the scrape of layer region and particle confinement in magnetically confined plasma devices. The electrically biased objects in the edge region inside tokamaks as well as in Linear plasma devices are known to influence the dynamics of...
Prof.
Leopoldo Soto
(Chilean Nuclear Energy Commission)
23/10/2018, 14:00
Poster
In a dense plasma focus (DPF) the plasma is compressed into a hot-warm dense pinch. Since, 50 years ago and during the first three decades the dense plasma focus (DPF) was studied as a possible device to produce dense transient plasmas for fusion research. The trend was to produce bigger devices over MJ stored energy and MA current through the plasma pinch, in order to increase the efficiency...
Dr
Pablo Garcia-Martinez
(CONICET - Centro Atomico Bariloche)
23/10/2018, 14:00
Poster
The interaction of energetic particles with MHD modes of different
types is a major concern for the next generation of experiments
involving burning plasmas. This issue arises in different contexts such as particle redistribution due to current driven instabilities (involving or not magnetic reconnection), activation of Alfven eigenmodes (AE) due to wave-particle interaction or loss of...
Dr
Alessandro Biancalani
(Max-Planck-Institut für Plasmaphysik)
23/10/2018, 14:00
Poster
It is getting increasingly clear that many tokamak plasma phenomena which have traditionally been investigated separately, are actually intrinsically linked. One outstanding example along these lines - which is investigated in the present contribution - is the the interaction between Alfven modes (AM), turbulence, and zonal structures (ZS), like zonal flows and geodesic acoustic modes....
Dr
Hongda He
(Southwestern institute of physics)
23/10/2018, 14:00
Poster
The toroidicity-induced Alfven eigenmode (TAE) excited by energetic ions was first simulated by using GTC code based on HL-2A experimental configuration. The simulation results show that the fraction of energetic (fast) ions in HL-2A experiments is about 3%. The TAE eigenmode frequency is around 211 kHz and is inversely proportional to the square root of electron density, which is...
Ms
Jiraporn Promping
(Thailand Institute of Nuclear Technology)
23/10/2018, 14:00
Poster
Self-consistent simulations of plasma in a proposed tokamak design of Thailand Tokamak. (major radius = 65 cm, minor radius = 20 cm, plasma current = 100 kA, toroidal magnetic field = 1.5 T) are carried out using the 1.5D BALDUR integrated predictive modeling code. The simulations are used to investigate plasma transport with on and off axis positions of ion cyclotron resonance heating (ICRH)...
Dr
Yurii V. Yakovenko
(Kyiv Institute for Nuclear Research, Kyiv, Ukraine)
23/10/2018, 14:00
Poster
Results of simulations of the sawtooth-induced redistribution of fast ions in JET and ITER with the code OFSEF are presented. The dependence of the redistribution on the particle parameters (energy and pitch angle) is studied. The redistribution of the trapped and marginally passing particles is found to exhibit barrier-like behaviour at the separatrix between the trapped and passing...
Dr
Hao WANG
(National Institute for Fusion Science)
23/10/2018, 14:00
Poster
Energetic particle driven geodesic acoustic modes (EGAMs) in the Large Helical Device (LHD) plasmas are investigated using MEGA code. MEGA is a hybrid simulation code for energetic particles (EPs) interacting with a magnetohydrodynamic (MHD) fluid. In the present work, both the conventional and extended models of MEGA are employed. In the conventional model, only the EPs are described by the...
Mr
Antti Snicker
(Aalto University)
23/10/2018, 14:00
Poster
This contribution aims to broaden the understanding of the interplay between the internal and
external 3D perturbations on the fast ions in tokamak plasmas. At first, we used simulations
using the ASCOT suite of codes to analyze an ASDEX Upgrade discharge showing clear sign
of the interplay between a (3,2) neoclassical tearing mode (NTM) and external RMP coils on
the fast ion loss detector...
Dr
David Zarzoso
(CNRS)
23/10/2018, 14:00
Poster
Energetic particles naturally exist in a tokamak due to either fusion reactions or external heating such as ICRH or NBI. These energetic particles need to be well-confined in order to transfer their energy to thermal particles and achieve this way a regime with self-sustained fusion reactions. However, energetic particles excite modes that tend to de-confine the particles themselves. This is...
Dr
Ling Zhang
(CnIPPCAS)
23/10/2018, 14:00
Poster
In EAST tokamak, H-mode discharges have been obtained without a basic change at various heating conditions after installation of tungsten monoblocks at upper divertor. Recently, a reproducible long pulse H-mode operation with sufficient tungsten suppression has succeeded for both electron cyclotron resonance and lower-hybrid wave heated discharges and various experimental approaches are also...
488.
Verification and Validation of Integrated Simulation of Energetic Particles in Toroidal Plasmas
Zhihong Lin
(UC Irvine)
23/10/2018, 14:00
Poster
Energetic particle (EP) pressure gradients in fusion plasmas can readily excite mesoscale EP instabilities such as the Alfven eigenmodes (AEs) and energetic particle modes that drive large EP transport, which can degrade overall plasma confinement and threaten the machine’s integrity. EP could strongly influence thermal plasma dynamics including the microturbulence and macroscopic...
