Heavy impurity transport in tokamaks subject to plasma rotation, NTV and the influence of saturated ideal MHD perturbations

2021 ◽  
Author(s):  
Eduardo Lascas Neto ◽  
Jonathan P Graves ◽  
Madhusudan Raghunathan ◽  
Cristian Sommariva ◽  
David Pfefferlé
Keyword(s):  
Magnetic Fields ◽  
Electric Field ◽  
High Performance ◽  
Plasma Rotation ◽  
Impurity Transport ◽  
Heavy Impurity ◽  
Outward Transport ◽  
Ideal Mhd ◽  
Plasma Configuration

Abstract Strongly peaked tungsten accumulation is a common feature of high performance plasma scenarios in JET with the ITER-like wall, particularly during MHD activity induced by m⁄n = 1⁄1 continuous modes. This study investigates the effect of 1⁄1 long living internal kink modes on heavy impurity transport in the presence of strong flows and NTV ambipolar electric field. A novel formulation which includes these effects is presented and applied in the VENUS-LEVIS code in order to follow tungsten ions in a saturated JET-like 1⁄1 internal kinked toroidally rotating plasma configuration. The synergy between 3D magnetic fields, strong flows and NTV is seen to cause tungsten accumulation in contrast to what is observed in similar axisymmetric configurations. Rapid inward transport of impurities in JET plasmas following the triggering of continuous 1⁄1 modes is explained by the work presented here, and we use the same theory to postulate why outward transport can occur in kinked ASDEX-U plasmas.

On the influence of a radial electric field on ripple-induced stochastic diffusion in tokamaks

2005 ◽  
Vol 71 (1) ◽  
pp. 81-96
Author(s):  
S. ASSAS ◽  
L.-G. ERIKSSON
Keyword(s):  
Electric Field ◽  
High Performance ◽  
Radial Electric Field ◽  
Diffusion Path ◽  
Real Space ◽  
Stochastic Motion ◽  
Stochastic Diffusion ◽  
Plasma Rotation ◽  
Transport Barriers ◽  
The Impact

Strong plasma rotation is an important feature in many high-performance fusion plasmas, especially in plasmas with internal transport barriers (ITBs). An analysis of the impact of plasma rotation, or more specifically of a radial electric field, on the ripple-induced stochastic diffusion of energetic ions is presented. In particular, the influence of a radial electric field on the threshold for stochastic motion and on the diffusion path in real space is investigated.

Photodiodes based on MAPbBr3/Bi3+ doped MAPbCl3 single crystals heterojunction for X-ray detection

CrystEngComm ◽  
2021 ◽  
Author(s):  
Yuzhu Pan ◽  
Xin Wang ◽  
Jingda Zhao ◽  
Yubing Xu ◽  
Yuwei Li ◽  
...  
Keyword(s):  
Electric Field ◽  
Single Crystals ◽  
External Electric Field ◽  
High Performance ◽  
X Ray

Perovskites single crystals (PSCs) could be used to made high performance photoelectric detectors due to its superior optoelectronic characteristics. Generally, external electric field need to be applied in the PSCs-based...

scholarly journals Magnetic properties of (Bi1−xLax)(Fe,Co)O3 films fabricated by a pulsed DC reactive sputtering and demonstration of magnetization reversal by electric field

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Munusamy Kuppan ◽  
Daichi Yamamoto ◽  
Genta Egawa ◽  
Sivaperuman Kalainathan ◽  
Satoru Yoshimura
Keyword(s):  
Electric Field ◽  
Magnetization Reversal ◽  
High Performance ◽  
Magnetic Domain ◽  
Magnetic Film ◽  
Film Plane ◽  
Force Microscopy ◽  
Domain Structures ◽  
Pulsed Dc ◽  
Submicron Scale

Abstract(Bi1−xLax)(Fe,Co)O3 multiferroic magnetic film were fabricated using pulsed DC (direct current) sputtering technique and demonstrated magnetization reversal by applied electric field. The fabricated (Bi0.41La0.59)(Fe0.75Co0.25)O3 films exhibited hysteresis curves of both ferromagnetic and ferroelectric behavior. The saturated magnetization (Ms) of the multiferroic film was about 70 emu/cm3. The squareness (S) (= remanent magnetization (Mr)/Ms) and coercivity (Hc) of perpendicular to film plane are 0.64 and 4.2 kOe which are larger compared with films in parallel to film plane of 0.5 and 2.5 kOe. The electric and magnetic domain structures of the (Bi0.41La0.59)(Fe0.75Co0.25)O3 film analyzed by electric force microscopy (EFM) and magnetic force microscopy (MFM) were clearly induced with submicron scale by applying a local electric field. This magnetization reversal indicates the future realization of high performance magnetic device with low power consumption.

scholarly journals Can Multi-threaded Flux Tubes in Coronal Arcades Support a Magnetohydrodynamic Avalanche?

Solar Physics ◽  
2021 ◽  
Vol 296 (8) ◽  
Author(s):  
J. Threlfall ◽  
J. Reid ◽  
A. W. Hood
Keyword(s):  
Magnetic Fields ◽  
Three Dimensional ◽  
Coronal Loops ◽  
Flux Tubes ◽  
Single Thread ◽  
Mhd Instabilities ◽  
Mhd Instability ◽  
Mhd Simulations ◽  
Ideal Mhd ◽  
Model Geometry

AbstractMagnetohydrodynamic (MHD) instabilities allow energy to be released from stressed magnetic fields, commonly modelled in cylindrical flux tubes linking parallel planes, but, more recently, also in curved arcades containing flux tubes with both footpoints in the same photospheric plane. Uncurved cylindrical flux tubes containing multiple individual threads have been shown to be capable of sustaining an MHD avalanche, whereby a single unstable thread can destabilise many. We examine the properties of multi-threaded coronal loops, wherein each thread is created by photospheric driving in a realistic, curved coronal arcade structure (with both footpoints of each thread in the same plane). We use three-dimensional MHD simulations to study the evolution of single- and multi-threaded coronal loops, which become unstable and reconnect, while varying the driving velocity of individual threads. Experiments containing a single thread destabilise in a manner indicative of an ideal MHD instability and consistent with previous examples in the literature. The introduction of additional threads modifies this picture, with aspects of the model geometry and relative driving speeds of individual threads affecting the ability of any thread to destabilise others. In both single- and multi-threaded cases, continuous driving of the remnants of disrupted threads produces secondary, aperiodic bursts of energetic release.

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