Numerical simulations of sawteeth in tokamaks

Numerical Simulations of Sawteeth in Tokamaks

Numerical simulations of sawteeth in tokamaks have been carried out using reduced magnetohydrodynamics and a simple transport model. The electron temperature is evolved self-consistently, including Ohmic heating and a highly anisotropic thermal diffusivity. The sawtooth period and collapse time found in the simulations for Lundquist numbers S below 10 compare favourably with experimental result...

TOkamaks and NUmerical Simulations

TOkamaks and NUmerical Simulations

Stabilization of sawteeth in tokamaks with toroidal flows

Sheared toroidal flows with a magnitude of the order of the sound speed are shown to stabilize sawteeth in tokamaks. In the absence of flows, tokamak equilibria in which the central safety factor q is less than unity are unstable to resistive tearing modes ~resistive internal kink modes! with toroidal mode number n51. As the ratio b of the plasma pressure to the magnetic field pressure increase...

NUMERICAL SIMULATIONS OF THE PHASE TRANSITIONS IN CLUSTERS

We have studied the phase transitions in atomic clusters by molecular dynamics simulation, assuming Lennard-Jones interatomic pair potential. Calculations are performed by DAP parallel computer. The results are analyzed by simulating their orientational distribution plots (dot-plot), and neutron diffraction patterns. It is shown that all the main features of the bulk phase transitions are e...