Self-consistent modeling of radio-frequency plasma generation in stellarators
- National Academy of Sciences of Ukraine, National Science Center Kharkov Institute of Physics and Technology (Ukraine)
A self-consistent model of radio-frequency (RF) plasma generation in stellarators in the ion cyclotron frequency range is described. The model includes equations for the particle and energy balance and boundary conditions for Maxwell’s equations. The equation of charged particle balance takes into account the influx of particles due to ionization and their loss via diffusion and convection. The equation of electron energy balance takes into account the RF heating power source, as well as energy losses due to the excitation and electron-impact ionization of gas atoms, energy exchange via Coulomb collisions, and plasma heat conduction. The deposited RF power is calculated by solving the boundary problem for Maxwell’s equations. When describing the dissipation of the energy of the RF field, collisional absorption and Landau damping are taken into account. At each time step, Maxwell’s equations are solved for the current profiles of the plasma density and plasma temperature. The calculations are performed for a cylindrical plasma. The plasma is assumed to be axisymmetric and homogeneous along the plasma column. The system of balance equations is solved using the Crank-Nicholson scheme. Maxwell’s equations are solved in a one-dimensional approximation by using the Fourier transformation along the azimuthal and longitudinal coordinates. Results of simulations of RF plasma generation in the Uragan-2M stellarator by using a frame antenna operating at frequencies lower than the ion cyclotron frequency are presented. The calculations show that the slow wave generated by the antenna is efficiently absorbed at the periphery of the plasma column, due to which only a small fraction of the input power reaches the confinement region. As a result, the temperature on the axis of the plasma column remains low, whereas at the periphery it is substantially higher. This leads to strong absorption of the RF field at the periphery via the Landau mechanism.
- OSTI ID:
- 22216068
- Journal Information:
- Plasma Physics Reports, Vol. 39, Issue 11; Other Information: Copyright (c) 2013 Pleiades Publishing, Ltd.; http://www.springer-ny.com; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-780X
- Country of Publication:
- United States
- Language:
- English
Similar Records
RF Plasma Production in Uragan-2M Torsatron
Self-contained solution to the spatially inhomogeneous electron Boltzmann equation in a cylindrical plasma positive column
Related Subjects
ABSORPTION
ANTENNAS
AXIAL SYMMETRY
CONVECTION
CYCLOTRON FREQUENCY
CYLINDRICAL CONFIGURATION
ELECTRON TEMPERATURE
ELECTRONS
ENERGY BALANCE
ENERGY LOSSES
EQUATIONS
FOURIER TRANSFORMATION
ION TEMPERATURE
LANDAU DAMPING
ONE-DIMENSIONAL CALCULATIONS
PLASMA DENSITY
RADIOWAVE RADIATION
SIMULATION
STELLARATORS
THERMAL CONDUCTION