Dr
Theresa Wilks
(UsMIT)
25/10/2018, 14:00
Poster
Analysis of pedestal characteristics for Quiescent H-mode (QH) and I-mode plasmas from recent experiments on DIII-D and C-Mod exhibit a growing understanding of the access requirements necessary to obtain edge fluctuations or MHD that drive edge particle transport needed to remain ELM-free. In DIII-D QH-mode plasmas, critical values of ExB shear are required in experiment in order to suppress...
Dr
Michael Bongard
(University of Wisconsin-Madison)
25/10/2018, 14:00
Poster
Robust non-solenoidal startup methods may simplify the cost and complexity of next-step burning plasma devices, and especially STs, by removing the need for a solenoid. Experiments on the $A\sim1$ Pegasus ST are advancing the physics and technology basis of Local Helicity Injection (LHI). LHI creates high-$I_p$ tokamak plasmas without a solenoid by injecting helicity with small current sources...
Dr
Silvana Nowak
(IFP - CNR , Milano, Italy)
25/10/2018, 14:00
Poster
Stability of JET baseline and hybrid scenarios from previous and present experimental campaign is investigated in the framework of the JET1 task on MHD analysis and modeling in support of scenario development. Modeling of Neoclassical Tearing Modes (NTMs) onset and their effect on heavy impurity transport is performed via the European Transport Simulator (ETS), encompassing an NTM module and...
Ms
AMRITA BHATTACHARYA
(INDIAN INSTITUTE OF TECHNOLOGY KANPUR)
25/10/2018, 14:00
Poster
The radial impurity transport equation describes the distribution of impurity ion species with different charge states perpendicular to magnetic surfaces of tokamak plasma. The impurity transport equation for each ion with ionization state Z is a second order, coupled, parabolic partial differential equation described in terms of number densities of charge states Z, Z-1 and Z+1. A...
Dr
Michael Cole
(Princeton Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
Whole-volume gyrokinetic simulations of stellarators are necessary to address a number of important physics and engineering issues, including energetic particle confinement op- timisation and turbulent transport prediction. In recent work, a whole-volume stellarator version of the global gyrokinetic Particle-In-Cell (PIC) code XGC[1] is under development. A 3D interpolation of equilibrium...
Dr
Michio Okabayashi
(Princeton Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
M. Okabayashi
Princeton Plasma Physics Laboratory, PO Box 451, Princeton, NJ 08543-0451, USA
mokabaya@pppl.gov
DIII-D experiments on control of locked tearing modes are in good qualitative
agreement with predictions of a non-linear reduced MHD code (AEOLUS-IT) [1].
Robust avoidance of locked tearing modes that may cause disruptions is a prerequisite
for successful ITER...
Mr
Houyang Guo
(General Atomics)
25/10/2018, 14:00
Poster
A Small Angle Slot (SAS) divertor has been installed on the DIII-D tokamak to further evaluate the role of divertor closure in achieving efficient heat dispersal for steady-state tokamaks. Initial experiments have shown a significant reduction of the electron temperature (T_e) across the divertor target and access to dissipative divertor operation at lower H-mode operational densities while...
Prof.
Cary Forest
(University of Wisconsin-Madison)
25/10/2018, 14:00
Poster
Abstract: We report an overview of theoretical and experimental work at the University of Wisconsin leading to a fusion neutron source based on the Gas Dynamic Trap concept. The design considers the implications of several recent physics and technological advances and uses (1) off-the-shelf MRI magnets for an inexpensive central cell, (2) state-of-the-art small and planar high field REBCO...
Dr
John deGrassie
(General Atomics)
25/10/2018, 14:00
Poster
Scaling of intrinsic rotation in DIII-D H-mode plasmas demonstrates a strong correlation with the ion temperature (Ti) and stored plasma thermal energy, indicating a coupling between the turbulent intrinsic momentum flux and the turbulent energy flux [1]. The empirical scaling [1] of intrinsic rotation with plasma stored energy has been recently explored by novel experiments on DIII-D that...
Dr
Steven Sabbagh
(Columbia University)
25/10/2018, 14:00
Poster
Disruption prediction and avoidance is a critical need for next-step tokamaks such as ITER, as disruptions can place significant thermal heat loads and electromagnetic forces on the device and can potentially lead to damage from runaway electrons. Meeting these challenging goals with the high reliability required for ITER and future tokamaks requires multiple approaches, including an...
Mr
B.A. Grierson
(Princeton Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
A novel capability has been added to the DIII-D neutral beam injection system, enabling in-shot variation of beam energy and current for the first time [1]. This new capability is now being explored as a tool for integrated control and optimization of equilibrium profiles and Alfvén eigenmode (AE) activity. The capability provides an alternative to the typically used pulse-width-modulation...
Dr
Nirmal Kumar Bisai
(Institute for Plasma Research, Bhat, Gandhinagar-382428, India)
25/10/2018, 14:00
Poster
High Z Impurity seeding/puffing is an important topic as it is capable to provide radiative improvement of confinement and disruption mitigation in future tokamaks. Here, in this work, numerically and experimentally, we investigate the effect of low density 1% Ne gas (Z = 10, A = 20) seeding and also massive gas puffing. Two dimensional electrostatic interchange turbulence simulation has been...
Dr
Ahmed Diallo
(PPPL)
25/10/2018, 14:00
Poster
Investigations of pedestal evolution between edge-localized-modes (ELMs) in DIII-D provide strong evidence that coupling of modes located near rational surfaces close to the separatrix leads to the onset of an ELM. While the peeling ballooning model is the leading candidate for the ELM phenomenology, the triggering mechanism is not yet understood and remains one of the most outstanding...
Dr
Tobias Görler
(DeMPIPGarc)
25/10/2018, 14:00
Poster
Although remarkable progress in ab initio nonlinear gyrokinetic plasma core turbulence studies has been seen in the last decade, some important open issues remain – e.g., in view of high performance discharges where magnetic fluctuations tend to reduce the turbulence levels and where the presence of fast ions may provide further significant stabilization enhancements. This effect was shown to...
Dr
Edward Hinson
(University of Wisconsin-Madison)
25/10/2018, 14:00
Poster
It is shown for the first time that global exhaust of helium, measured by effective helium particle confinement time (𝛕p,He), is improved during edge localized mode (ELM) suppression by resonant magnetic field perturbations (RMP) in high confinement (H-mode) ITER-shaped tokamak plasmas at DIII-D. An up to 40% reduction of 𝛕p,He during RMP-ELM suppression compared to ELMy H-mode discharges...
Nathaniel Ferraro
(Princeton Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
Results from the 2016 NSTX-U campaign and the subsequent recovery effort have led to significant new insights regarding error fields in the NSTX-U experiment in particular, and in spherical tokamak configurations in general. During the experimental campaign, many L-mode discharges were found to be locked from the q=2 surface outward, indicating the presence of error fields. At the conclusion...
Dr
Jayson Barr
(General Atomics)
25/10/2018, 14:00
Poster
Recent experiments on DIII-D and EAST are developing the techniques and scientific understanding that ITER and future devices will need for safe, low-disruptivity shutdown. ITER needs options for reliable termination both in normal operation as well as in response to an off-normal event, where speed to soft landing is paramount. A large survey of ramp-down techniques in a variety of DIII-D...
Dr
Bart Van Compernolle
(University of California, Los Angeles)
25/10/2018, 14:00
Poster
Recent work on ICRF physics at the Large Plasma Device (LAPD) at UCLA has focused on deleterious near-field antenna effects, such as RF rectification, sputtering, convective cells and power lost to the plasma edge. Plasma parameters in LAPD are similar to the scrape-off layer of current fusion devices. The machine has a 17 m long, 60 cm diameter magnetized plasma column with typical plasma...
Dr
Alberto Loarte
(ITER Organization)
25/10/2018, 14:00
Poster
RMP ELM suppression experiments at ITER-like conditions (shape, collisionality, RMP spectrum) in DIII-D show little splitting of the heat flux to the divertor targets, despite robust splitting in the particle flux. This lack of divertor heat flux splitting is a potentially important result for ITER because splitting of the divertor heat flux into multiple lobes displaced from the primary...
Prof.
Zhihong Lin
(UsUCALIrv)
25/10/2018, 14:00
Poster
Experimental progress by TAE Technologies has led to successful suppression of MHD instabilities in field-reversed configuration (FRC) plasmas using C-2U and C-2W devices. Resultant particle and energy confinement times are on the order of several milliseconds, governed by micro-turbulence driven transport processes. Understanding these mechanisms is essential towards improved confinement and...
Dr
Daniel López-Bruna
(EsLNF)
25/10/2018, 14:00
Poster
In toroidal magnetic confinement fusion research, one-dimensional (1D) transport models rely on one radial coordinate that labels nested toroidal flux surfaces. The presence of magnetic islands in the magnetic geometry does not impede making 1D transport calculations if the island regions are excluded and then, if necessary, treated separately. In this work we show a simple way to modify the...
Dr
Mario Podesta
(Princeton Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
Global Alfvén eigenmodes (GAE) have been extensively studied on NSTX and with analytic and numerical modeling. Multiple GAE with a range of toroidal mode numbers are commonly observed in NSTX plasmas heated with neutral beams. Recently, analytic and numerical modeling has been used to very successfully model the suppression of GAE experimentally observed with the injection of high pitch (V||/V...
Ms
Emi Narita
(National Institutes for Quantum and Radiological Science and Technology)
25/10/2018, 14:00
Poster
A novel quasilinear particle transport model is constructed by joint analyses with gyrokinetic calculations and JT-60U experimental data. The new model deals with the diagonal (diffusion) and off-diagonal (pinch) transport mechanisms individually. Besides the decomposition, realistic particle sources from neutral-beam fueling are taken into account, which have not been discussed in earlier...
Dr
Max Austin
(UsIFS)
25/10/2018, 14:00
Poster
Discharges with negative triangularity (-delta) shape have been created in DIII-D with H-mode-like confinement (H98y2 = 1.2) and high normalized beta (beta_N = 2.6) with L-mode-like edge pressure profiles and no ELMs. These inner-wall-limited plasmas with delta = -0.4 had the same global performance as a positive triangularity (delta = +0.4) ELMing H-mode discharge with the same I_p,...
Dr
Thomas W. Petrie
(General Atomics)
25/10/2018, 14:00
Poster
Enhanced radiation has been used to reduce divertor heat flux in high power, high performance (AT) double null divertor (DND) and near-DND plasmas in DIII-D, while at the same time maintaining acceptable energy confinement and particle control. Effective radiating mantle operation in high power AT plasma depended strongly on the location of electron cyclotron (EC) heating deposition, on...
Dr
Kathreen Thome
(Oak Ridge Associated Universities)
25/10/2018, 14:00
Poster
Three high-frequency modes observed in the DIII-D tokamak have been identified as energetic particle instabilities driven unstable by anisotropic fast ions and runaway electrons. These modes could serve as control tools of the energetic particle distribution in fusion-relevant plasmas. (1) Whistler waves with w>>wci, excited by multi-MeV runaway electrons in a low-density (ne~1019 m-3) plasma,...
Dr
Nicholas Eidietis
(General Atomics)
25/10/2018, 14:00
Poster
A finite-state off-normal and fault response (ONFR) system is presented that provides the required supervisory logic for robust disruption avoidance and machine protection in tokamaks. Robust event handling is critical for ITER and future large tokamaks, where plasma parameters will necessarily approach stability limits and many systems will operate near their engineering limits. The ONFR...
Dr
Jeffrey Herfindal
(Oak Ridge National Laboratory)
25/10/2018, 14:00
Poster
Experiments on DIII-D have injected multiple shattered pellets at different toroidal locations for the first time, as is planned for the ITER disruption mitigation system. Systematically varying the relative timing of the two pellets suggests that simultaneously injected pellets may impact the assimilation of each other, altering the resulting disruption characteristics compared to that due to...
Dr
Tyler Abrams
(General Atomics)
25/10/2018, 14:00
Poster
Measured intra-ELM (during ELMs) tungsten erosion profiles in the DIII-D divertor, acquired via W-I spectroscopy with high temporal and spatial resolution, are consistent with OEDGE+SDTrim.SP modeling including measured ion saturation currents and ion impact energies. If pedestal temperature rather than divertor conditions are used as input, quantitative agreement is observed, for the first...
Dr
Doohyun Kim
(Princeton Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
The effects of sawtooth on fast ion transport have been studied in reproducible, 2 seconds long sawtoothing L-mode discharges during the 2016 experimental campaign on National Spherical Torus Experiment Upgrade (NSTX-U). Experimental observations through Solid State Neutral Particle Analyzer (SSNPA) and Fast-Ion D-alpha (FIDA) diagnostics show that passing particles within the measured energy...
Dr
Boonyarit Chatthong
(Department of Physics, Faculty of Science, Prince of Songkla University)
25/10/2018, 14:00
Poster
This work uses CRONOS integrated predictive modelling code to simulate ion and electron temperatures of plasma scenarios based on a future Thailand tokamak. This small tokamak is planned to be installed at Thailand Institute of Nuclear Technology (TINT), under the collaboration of the Center for Plasma and Nuclear Fusion Technology (CPaF). The plasma transport includes both neoclassical, via...
Dr
Masanori Nunami
(National Institute for Fusion Science)
25/10/2018, 14:00
Poster
The first comprehensive analyses of kinetic simulations for anomalous and neoclassical transport of steady state multi-ion-species plasmas including impurity ions in helical systems are performed by gyrokinetic and drift-kinetic approaches.
To design the fusion reactors, the transport phenomena of plasma particles and heat need to be quantitatively predicted, and numerical simulation...
Dr
Robert Granetz
(MIT)
25/10/2018, 14:00
Poster
We find that disruption prediction using machine learning (ML), trained on
large databases containing only plasma parameters that are available in
real time on C-Mod, DIII-D, and EAST, differ substantially in performance
among the three machines, implying that a universal real time disruption
warning algorithm may be problematic. This could have important
implications for disruption...
Dr
Ezekial Unterberg
(Oak Ridge National Laboratory)
25/10/2018, 14:00
Poster
DIII-D carried out experiments using novel, isotopic tungsten (W) tracer sources in the outer divertor and has characterized how the W leakage from this region depends on botz the exact source location and ELM behavior. The W sources are toroidally-symmetric and poloidally-localized to two regions: (1) the outer strike point (OSP), a natural-W source; and (2) the far-target, i.e., 3-5 heat...
Dr
Orso Meneghini
(General Atomics)
25/10/2018, 14:00
Poster
An integrated modeling workflow capable of finding the steady-state solution with self-consistent core transport, pedestal structure, current profile, and plasma equilibrium physics has been developed, validated against several DIII-D discharges, and used to perform predictions for a 15 MA D-T ITER baseline scenario. Key features of the proposed core-pedestal coupled workflow are its ability...
Dr
Lei Qi
(National Fusion Research Institute of South Korea)
25/10/2018, 14:00
Poster
One of the long lived conundrums in ohmically heated plasmas is that the energy confinement time τ_E shows a transition from a linear regime proportional to the density (LOC) to a saturation regime (SOC) weakly dependent on the density. In the viewpoint of the first principle nonlinear global gyrokinetic simulations, we here present an investigation of LOC to SOC transition for the first time....
Mr
Giuseppe Telesca
(IPPILM Poland)
25/10/2018, 14:00
Poster
This paper is focused on the simulation of JET ELMy H-mode pulses pertaining to the baseline scenario with medium-high electron density, n_e, and auxiliary power, P_aux, in excess of 30 MW. The auxiliary heating is provided mostly by NBI, while ICRF heating does not exceed 5 MW. We have considered two pulses (Ip=3 MA, Bt= 2.8 T) at n_e = 6.5-7x10^19 m^-3 which show very high neutron rates and...
Seung Gyou Baek
(MIT PSFC)
25/10/2018, 14:00
Poster
Efficient lower hybrid current drive (LHCD) at high plasma density has been demonstrated on Alcator C-Mod for the first time with the reduction in the Greenwald fraction by raising the plasma current.
In order to attain, steady-state advanced tokamak operation, efficient off-axis current drive is required. LHCD is highly desirable because it has the highest efficiency of all technologies...
Morgan Shafer
(Oak Ridge National Laboratory)
25/10/2018, 14:00
Poster
Experimental evidence of the formation of multiple helicity island chains during the mode locking phase preceding plasma disruption is providing a clear picture for the understanding of locked-mode triggered disruptions. This emerging picture uses measurements from a new dual soft x-ray (SXR) tangential imaging system that measures localized internal perturbations in combination with local...
Mr
Anthony Leonard
(General Atomics)
25/10/2018, 14:00
Poster
A comparison of experiment and modeling of detached divertor plasmas in DIII-D is examined in the context of parallel energy transport due to electron conduction and plasma convection in order to validate and improve models used for divertor design. Power balance analysis is carried out to determine parallel heat flux and energy dissipation as a function of distance from the divertor target....
Dr
Siriyaporn Sangaroon
(Mahasarakham University)
25/10/2018, 14:00
Poster
A small tokamak is planned to be installed in Thailand at Thailand Institute of Nuclear Technology (TINT), Ongkarak campus in Nakorn Nayok, under the collaboration of the Center for Plasma and Nuclear Fusion Technology (CPaF). One of the great challenges subject in operating this tokamak is to gain better understanding of the impurities behavior because the impurities are responsible for the...
Prof.
Saskia Mordijck
(The College of William and Mary)
25/10/2018, 14:00
Poster
Exploration of particle transport behavior in multiple devices shows the importance of turbulence in determining particle confinement and the density profile. Behavior on CMOD indicates that as plasma parameters approach ITER, the pedestal and SOL become increasingly opaque. H-mode experiments with density pedestals approaching $4 \times 10^{20}$ $m^{-3}$, heated with the maximum auxiliary...
Dr
Zhanhui Wang
(Southwestern Institute of Physics)
25/10/2018, 14:00
Poster
Plasma fueling with higher efficiency and deeper injection is crucial to enable fusion power performance requirements at high density for next generation devices such as ITER. Compared to pellet injection fueling method, it penetrates shallower for the fueling methods of supersonic molecular beam injection (SMBI) and gas puffing (GP). SMBI is one method of deuterium gas jet injection. Fast...
Prof.
Eugenio Schuster
(Lehigh University)
25/10/2018, 14:00
Poster
Recent and ongoing experiments on DIII-D demonstrate the potential of model-based real-time optimization for the realization of advanced steady-state scenarios by tightly regulating the $q$ profile and $\beta_N$ (or the plasma energy $W$) simultaneously. A primary goal for the DIII-D research program over the next five years is to develop the physics basis for a high $q$ ($q_{\text{min}}>2$),...
Dr
Simon Pinches
(ITER Organization)
25/10/2018, 14:00
Poster
The ITER Integrated Modelling & Analysis Suite (IMAS) is the software infrastructure that is being developed using expertise from across the research facilities within the ITER Members to meet the needs of the ITER Integrated Modelling Programme. It builds around a standardised representation of data described by a Data Dictionary that is both machine independent and extensible. Machine...
Dr
Adam McLean
(Lawrence Livermore National Laboratory)
25/10/2018, 14:00
Poster
Experimental observations of extreme ultraviolet resonance emissions in the divertor of DIII-D are used to quantitatively account for radiated power from molecular, atomic and ionized plasma constituents through the transition to detachment. Deuterium emission is found to be the primary emitter near the target scrape-off layer regions while the main impurity in DIII-D, carbon, is found to...
Dr
B.A. Grierson
(Princeton Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
Recent experiments in the DIII-D tokamak obtained low torque MHD-free H-mode discharges approaching ITER baseline conditions revealing mid-radius rotation profile hollowing associated with turbulent transport. This indicates that hollowing of toroidal rotation profiles that occurs prior to onset of large-scale MHD observed in low torque ITER Baseline conditions is not due to pre-existing MHD...
Dr
Luis F. Delgado-Aparicio
(Princeton Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
The computation of rotation-induced electrostatic potentials is currently being used to study the associated two-dimensional distribution of impurity density asymmetries in NSTX and NSTX-U plasmas. The main effect of toroidal rotation on heavy impurities is their radial displacement to the outer plasma, which result in a non-uniform distribution around a magnetic flux-surface. Due to the...
Prof.
Paul Terry
(University of Wisconsin-Madison)
25/10/2018, 14:00
Poster
An analytic saturation theory for toroidal ion temperature gradient turbulence is derived
from a well-known fluid model, providing the saturated levels of the unstable fluctuation, a
nearly conjugate stable mode, and the zonal flow, along with their dependencies on the
model parameters. The theory utilizes the eigenmode decomposition of the dynamical
equations, applies statistical closure,...
Dr
Weixing Wang Wang
(Princeton University Plasma Physics Laboratory)
25/10/2018, 14:00
Poster
Plasma self-generated current (e.g., the bootstrap current) contributes to the generation of poloidal magnetic field for plasma confinement in tokamaks, and also strongly affects key MHD instabilities. It is found that plasma turbulence may strongly influence self-driven current generation. This could have a radical impact on various aspects of tokamak physics. Our simulation study employs a...
Prof.
Hiroyuki Yamaguchi
(National Institute for Fusion Science, National Institutes of Natural Science)
25/10/2018, 14:00
Poster
Electrostatic potential $\Phi_{\rm NBI}$ generated by the neutral-beam-injection (NBI) to the plasma, and its effect on the neoclassical transport of carbon impurity ions in the Large Helical Device (LHD) are investigated for the first time by means of the global drift-kinetic simulations. The ripple-trapped beam ions of the perpendicular NBI (40keV) have been found to generate $\Phi_{\rm...
Mr
Debraj Mandal
(Institute for Plasma Research)
25/10/2018, 14:00
Poster
The physics of particle and energy transport in collision-less plasmas presents substantial challenge because of largely linear threshold based plasma turbulence are replaced by their nonlinear counterparts capable of operating at smaller amplitudes. An outstanding property for collision-less plasmas is the essential nonlinear character of coherent structures supported by them at small...
387.
The Effect of RMP ELM Control for ITER on Pedestal Pressure Compared to EPED No-RMP Predictions
Dr
Max Fenstermacher
(Lawrence Livermore National Lab)
25/10/2018, 14:00
Poster
The ITER baseline and alternate scenarios use 3D Resonant Magnetic Perturbation (RMP) fields to control ELMs, and therefore ITER operating scenario (IOS) analysis needs to include the effect of the 3D fields on the pedestal pressure and overall device performance. In IOS analysis, the pedestal pressure, for a given pedestal density, will be predicted with the EPED code. Neural net...
Dr
Florian M. Laggner
(Princeton University)
25/10/2018, 14:00
Poster
For wide ranges of operational parameters and in machines with different wall materials, the inter-ELM pedestal profile evolution was robustly linked to characteristic fluctuations, indicating that universal instabilities dominate the pedestal structure and its dynamics in between edge localized modes (ELMs). The presented results substantially advance the comprehension of the underlying...
Prof.
Lu Wang
(International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics, State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology)
25/10/2018, 14:00
Poster
We present new results in the theory of turbulence driven intrinsic rotation and current. Both the intrinsic rotation and the intrinsic current driven by micro-turbulence are important for ITER. The former is critical for ITER due to its important role in suppressing MHD instabilities, since neutral beam injection may not provide enough external rotation drive in ITER. The latter is important...
Dr
Choong-Seock Chang
(Princeton Plasma Physics Laboratory and KAIST)
25/10/2018, 14:00
Poster
First-principles-based multiscale neoclassical-and-turbulent understanding of the impurity transport and its effect on the main plasma confinement is one of the most important subjects in magnetic fusion research. Seeding of impurity particles was found to improve the plasma confinement in the so-called “RI-mode” of operation [Weynants et al., Nucl. Fusion 39 (1999)]. More recently tungsten...
Dr
Par Strand
(Space, Earth and Environment, Chalmers University of Technology, SE-41296, Göteborg. Sweden)
25/10/2018, 14:00
Poster
The European Transport Simulator (ETS) [1] has been developed under the EUROfusion Integrated Modelling (EU-IM) effort [2] to meet the requirements for scenario development of burning plasmas. The ETS focuses both on interpretive and predictive modelling and is now being deployed for broader exploitation, e.g. on the JET computing infrastructure for close integration and use in support of JET...
Mr
Stefan Buller
(Chalmers University of Technology)
25/10/2018, 14:00
Poster
Highly charged impurities both dilute plasmas and lead to radiation losses, and thus cannot be allowed to accumulate in the core of a magnetic confinement fusion reactor. For stellarators, the outlook has been particularly pessimistic, as early theories predicted that impurities would unavoidably be transported inwards in the core.
However, recent theoretical work has shown that strong...
Dr
Guoqiang Li
(Institute of Plasma Physica, CAS)
25/10/2018, 14:00
Poster
In the past two years, two major scenarios were developed on the EAST tokamak, the long pulse steady state scenario and the high $\beta_N$ scenario. For the steady state scenario, 100 s long pulse discharge was achieved with only radio frequency heating and current drive (CD) and it has improved confinement with H98~1.1. For the high $\beta_N$ scenario, the $\beta_N$ ~2.0 was sustained for ~2...
Dr
Julio Martinell
(Nuclear Sciences Institute, National Autonomous University of Mexico)
25/10/2018, 14:00
Poster
Electrostatic drift waves produce transport by the E X B motion of a particle guiding center (GC) which can be studied from a Hamiltonian description where the electrostatic potential plays the role of the Hamiltonian. Here, the fluctuating potential is considered to be an infinite spectrum of waves, characteristic of weak turbulence, in two-dimensions. This is studied using a map that...
