Transcript Collisionless Reconnection

Plasma Studies at DUT
Xiaogang Wang
Center for Plasma Science & Technology
Department of Physics
College of Advanced Science & Technology
Dalian University of Technology
May 2006, Dalian, China
OUTLINE
•
•
•
•
Overview
Plasma Theory & Simulation Team
Fusion Related Research
Brief Summary
Overview
• Plasma Physics Program at Department of
Physics
– Faculty
• > 20 with 2 Chair Professors and 3 Outstanding
Young Career Awardees
– Graduate Program since 1982
• Enrollment: 25 students
• Graduate > 10 PhDs annually
– Undergraduate Program since 1998
• Enrollment: 30/60 alternatively
Overview
• University Center for Plasma Science &
Technology
– State Key Disciplinary (2 Nationwide)
– 40+ faculty and 200+ graduate students
– Plasma branch and theory & simulation arm of
State Key Lab of Materials Modification by
Beams
– Research labs over the university (School of
Environment Science, School of Chemical
Technology, School of Life Science, School of
Electronics & Info Technology)
Overview
• College of Advanced Science &
Technology (CAST)
– Fusion Energy & Plasma Physics
– Space Plasma Physics
– Computational Physics &
Applications
Overview
• Research activities
– MCF Plasma Physics
– Space Plasma Physics (DSP-Cluster)
– Plasma Proceedings (Plasma-Wall
Interactions)
– Atmospheric Pressure Plasma Glow
Discharge
– Plasma Sources
– Beam Physics (Low Power, High Current
Beams)
– Other Industry Applications
Plasma Theory & Simulation
• University supported research
team for Basic Plasma Physics
• A Faculty of 5 and 40+ graduate
students
• ~ RMB 1M annual research budget
• Associated with SWIP, USTC, ZJU,
HIT, PKU, NPU
Fusion Related Research
• Fast magnetic reconnection
– Hall MHD reconnection
– Unmagnetized ions and agnetized
electrons
– Length scale of ion inertial length di
Fusion Related Research
• Sawtooth crashes in Tokamaks
– Wang et al, PRL 70, 1627 (1993): in
sawtooth crashes (m=1 king-tearing mode)
V  B 4 dJ  Pe J  B
E
 2


c
w pe dt
ne
nec
– Reconnection ribbon width scaled by
D=VA/Wi=di
– Reconnection ribbon length
rsq0=rswA/Wi=(dirs)1/2
Fusion Related Research
Sawtooth crashes in Tokamaks
Wang et al, PRL 70, 1627
(1993):
Sawtooth crashes in Tokamaks
In Wang et al, PRL 70, 1627
(1993):
Fusion Related Research
• Mode-locking due to error field
– Previous work in resistive tearing
regime
– Current research:
• Neoclassical effects?
• Error field on double-tearing modes?
• Toroidal rotations?
Fusion Related Research
• Resistive wall modes (RWM)
– Rotating wall to stabilize RWM
– Differential rotation of plasmas
– Wesson, Phys. Plasma 5, 3816(1998):
• The plasma rotation would generate another type
of RMW Vrotation > sqr(2)VA
– Further studies:
• Compressibility: Vrotation > cs
– Our research (linear, numerical): S. Y. Cui
tomorrow afternoon
J. A. Wesson, Phys. Plasma 5, 3816 (1998)
Brief Summary
• A strong plasma program DLUT a
wide spectrum
• A strong education basis also
• Fusion studies are picking up
• Collaborations needed