Local Three-Dimensional MHD Simulations of the Parker Instability in Differentially Rotating Disks

1998 ◽  
pp. 321-324
Author(s):  
T. Matsuzaki ◽  
R. Matsumoto ◽  
T. Tajima ◽  
K. Shibata
Keyword(s):  
Three Dimensional ◽  
Rotating Disks ◽  
Mhd Simulations

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.

Three-dimensional MHD simulations of X-ray emitting subcluster plasmas in cluster of galaxies

2005 ◽  
Vol 36 (4) ◽  
pp. 636-642 ◽  
Author(s):  
N. Asai ◽  
N. Fukuda ◽  
R. Matsumoto
Keyword(s):  
Three Dimensional ◽  
X Ray ◽  
Cluster Of Galaxies ◽  
Mhd Simulations

scholarly journals Three-Dimensional MHD Simulations of a Subcluster Plasma Moving in Turbulent ICM

2006 ◽  
Vol 2 (S235) ◽  
pp. 189-189
Author(s):  
N. Asai ◽  
N. Fukuda ◽  
R. Matsumoto
Keyword(s):  
Heat Conduction ◽  
Magnetic Fields ◽  
Three Dimensional ◽  
Cold Fronts ◽  
Mhd Simulations ◽  
Anisotropic Heat Conduction ◽  
Magnetohydrodynamic Simulations

AbstractWe carried out 3D magnetohydrodynamic simulations of a subcluster moving in turbulent ICM by including anisotropic heat conduction. Since magnetic fields stretched along the subcluster surface suppress the heat conduction across the front, cold fronts are formed and sustained.

VIBRATION OF CIRCULAR BLADED DISK WITH IMPERFECTIONS

2011 ◽  
Vol 21 (10) ◽  
pp. 2893-2904 ◽  
Author(s):  
LADISLAV PŮST ◽  
LUDĚK PEŠEK
Keyword(s):  
Dynamic Properties ◽  
Single Point ◽  
Three Dimensional ◽  
Rotating Disk ◽  
Fe Model ◽  
Rotating Disks ◽  
Response Curves ◽  
State Response ◽  
Bladed Disk ◽  
Linear Damping

The steady state response of a model of circular bladed disk with imperfection is investigated. Disk imperfection results from additional two groups of damping heads fixed on opposite ends of one diameter. These damping heads are introduced into the computing model as additional point mass, damping and stiffness. Such type of imperfection causes the bifurcation of double eigenfrequencies into pairs of close eigenfrequencies. The effect of imperfection is examined both numerically on three-dimensional nonrotating FE-model and analytically on a simplified split 2DOF model of rotating disk excited by single point harmonic force. Nonlinear friction connection is analyzed and equivalent linear damping coefficient is derived and used in the calculation procedure. It is shown that nonproportional distribution of damping strongly influences the high of resonance peaks. Some examples of response curves illustrate the dynamic properties of stationary and rotating disks with mass-damping-stiffness imperfection.

Flow of a fourth grade fluid between rotating disks

2020 ◽  
Vol 34 (10) ◽  
pp. 2050091
Author(s):  
A. M. Siddiqui ◽  
Ayesha Sohail ◽  
Khush Bakhat Akram ◽  
Qurat-ul-Ain Azim
Keyword(s):  
Nonlinear Models ◽  
Fluid Model ◽  
Three Dimensional ◽  
Fourth Grade ◽  
Perturbation Approach ◽  
Rotating Disks ◽  
Highly Nonlinear ◽  
Rotating Surface ◽  
Grade Fluid ◽  
Fourth Grade Fluid

Flow of fluids between rotating surface is encountered in many industrial, manufacturing, mixing and biological processes. These fluids are complex, exhibit various rheological characteristics, and thus follow highly nonlinear models. In this paper, we have used fourth grade fluid model to represent fluids involved in such processes. The steady flow between two coaxial rotating disks is modeled. The resulting highly nonlinear equations are solved using perturbation approach. The velocity field in three-dimensional cylindrical coordinate system is reported. The results are then simulated to present a visual understanding of the flow.

Interpretation of vega observations at comet halley applying three-dimensional MHD simulations

2000 ◽  
Vol 25 (1-2) ◽  
pp. 153-156 ◽  
Author(s):  
M. Tátrallyay ◽  
M.I. Verigin ◽  
K. Szegö ◽  
T.I. Gombosi ◽  
K.C. Hansen ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Mhd Simulations ◽  
Comet Halley
Sign in / Sign up

Export Citation Format

Share Document