scholarly journals Optimized loading for particle-in-cell gyrokinetic simulations

2004 ◽  
Vol 82 (8) ◽  
pp. 609-622
Author(s):  
J L.V Lewandowski
Keyword(s):  
Configuration Space ◽  
Electrostatic Potential ◽  
Good Accuracy ◽  
Particle Loading ◽  
Random Loading ◽  
Conservation Of Energy ◽  
Particle In Cell ◽  
Long Wavelength ◽  
Gyrokinetic Simulations ◽  
52.35 Py

The problem of particle loading in particle-in-cell gyrokinetic simulations is addressed using a quadratic optimization algorithm. Optimized loading in configuration space dramatically reduces the short-wavelength modes in the electrostatic potential that are partly responsible for the nonconservation of total energy; further, the long-wavelength modes are resolved with good accuracy. As a result, the conservation of energy for the optimized loading is much better that the conservation of energy for the random loading. The method is valid for any geometry and can be coupled to optimization algorithms in velocity space. PACS Nos.: 52.35.Py, 52.30.Jb, 52.55.Fa

scholarly journals Nonlinear δ f particle in cell gyrokinetic simulations of the microtearing mode

2020 ◽  
Vol 27 (4) ◽  
pp. 042309 ◽  
Author(s):  
J. Chowdhury ◽  
Yang Chen ◽  
Scott E. Parker
Keyword(s):  
Particle In Cell ◽  
Gyrokinetic Simulations

An explicit large time step particle-in-cell scheme for nonlinear gyrokinetic simulations in the electromagnetic regime

2016 ◽  
Vol 23 (3) ◽  
pp. 032501 ◽  
Author(s):  
R. Kleiber ◽  
R. Hatzky ◽  
A. Könies ◽  
A. Mishchenko ◽  
E. Sonnendrücker
Keyword(s):  
Large Time ◽  
Time Step ◽  
Particle In Cell ◽  
Large Time Step ◽  
Gyrokinetic Simulations

scholarly journals Global gyrokinetic simulations of ITG turbulence in the magnetic configuration space of the Wendelstein 7-X stellarator

2020 ◽  
Vol 62 (10) ◽  
pp. 105005
Author(s):  
A Bañón Navarro ◽  
G Merlo ◽  
G G Plunk ◽  
P Xanthopoulos ◽  
A von Stechow ◽  
...  
Keyword(s):  
Configuration Space ◽  
Magnetic Configuration ◽  
Gyrokinetic Simulations

Particle-in-cell δf gyrokinetic simulations of the microtearing mode

2016 ◽  
Vol 23 (1) ◽  
pp. 012513 ◽  
Author(s):  
J. Chowdhury ◽  
Yang Chen ◽  
Weigang Wan ◽  
Scott E. Parker ◽  
W. Guttenfelder ◽  
...  
Keyword(s):  
Particle In Cell ◽  
Gyrokinetic Simulations

Numerical loading of a Maxwellian probability distribution function

2003 ◽  
Vol 81 (8) ◽  
pp. 989-996 ◽  
Author(s):  
J L.V Lewandowski
Keyword(s):  
Distribution Function ◽  
Probability Distribution ◽  
Nonlinear Equations ◽  
Probability Distribution Function ◽  
Low Noise ◽  
Electron Dynamics ◽  
Renormalization Procedure ◽  
Particle In Cell ◽  
Velocity Moments ◽  
52.35 Py

A renormalization procedure for the numerical loading of a Maxwellian probability distribution function (PDF) is formulated. The procedure, which involves the solution of three coupled nonlinear equations, yields a numerically loaded PDF with improved properties for higher velocity moments. This method is particularly useful for low-noise particle-in-cell simulations with electron dynamics. PACS Nos.: 52.35.Py, 52.30.Jb, 52.55.Fa

scholarly journals Gyrokinetic simulations on many- and multi-core architectures with the global electromagnetic Particle-In-Cell Code ORB5

2020 ◽  
pp. 107208 ◽  
Author(s):  
Noé Ohana ◽  
Claudio Gheller ◽  
Emmanuel Lanti ◽  
Andreas Jocksch ◽  
Stephan Brunner ◽  
...  
Keyword(s):  
Particle In Cell ◽  
Gyrokinetic Simulations

Acceleration of cold ions at separatrices of symmetric collisionless magnetic reconnection

2020 ◽  
Author(s):  
Evgeny Gordeev ◽  
Andrey Divin ◽  
Ivan Zaitsev ◽  
Vladimir Semenov ◽  
Yuri Khotyaintsev ◽  
...  
Keyword(s):  
Electric Field ◽  
Magnetic Reconnection ◽  
Electric Fields ◽  
Electrostatic Potential ◽  
Potential Drop ◽  
Local Electron ◽  
One Dimensional ◽  
Particle In Cell ◽  
Background Population ◽  
Cold Ions

<p>Separatrices of magnetic reconnection host intense perpendicular Hall electric fields produced by decoupling of ion and electron components and associated with the in-plane electrostatic potential drop between inflow and outflow regions. The width of these structures is several local electron inertial lengths, which is small enough to demagnetize ions as they cross the layer. We investigate temperature dependence of ion acceleration at separatrices by means of 2D Particle-in-Cell (PIC) simulations of magnetic reconnection with only cold or hot ion background population. The separatrix Hall electric field is balanced by the inertia term in cold background simulations, the effect indicative of the quasi-steady local perpendicular acceleration. The electric field introduces a cross-field beam of unmagnetized particles which makes the temperature strongly non-gyrotropic and susceptible to sub-ion scale instabilities. This acceleration mechanism nearly vanishes for hot ion background simulations. Particle-in-cell simulations are complemented by one-dimensional test particle calculations, which show that the hot ion particles experience scattering in energies after crossing the accelerating layer, whereas cold ions are uniformly energized up to the energies comparable to the electrostatic potential drop between the inflow and outflow regions.</p>

scholarly journals Numerics and computation in gyrokinetic simulations of electromagnetic turbulence with global particle-in-cell codes

2021 ◽  
Vol 63 (8) ◽  
pp. 084007
Author(s):  
A Mishchenko ◽  
A Biancalani ◽  
A Bottino ◽  
T Hayward-Schneider ◽  
Ph Lauber ◽  
...  
Keyword(s):  
Particle In Cell ◽  
Gyrokinetic Simulations

Redox Reactions in Lipid Membranes as a Model for Primordial Energy-Conserving Systems

1997 ◽  
Vol 161 ◽  
pp. 437-442
Author(s):  
Salvatore Di Bernardo ◽  
Romana Fato ◽  
Giorgio Lenaz
Keyword(s):  
Experimental Evidence ◽  
Lipid Membranes ◽  
Energy Supply ◽  
Redox Reactions ◽  
Living Systems ◽  
Asymmetric Distribution ◽  
Conservation Of Energy ◽  
Asymmetrical Distribution ◽  
Energy Conserving ◽  
Living Organisms

AbstractOne of the peculiar aspects of living systems is the production and conservation of energy. This aspect is provided by specialized organelles, such as the mitochondria and chloroplasts, in developed living organisms. In primordial systems lacking specialized enzymatic complexes the energy supply was probably bound to the generation and maintenance of an asymmetric distribution of charged molecules in compartmentalized systems. On the basis of experimental evidence, we suggest that lipophilic quinones were involved in the generation of this asymmetrical distribution of charges through vectorial redox reactions across lipid membranes.

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