Monte Carlo simulation study of the ICRF minority heating in the large helical device
Abstract
A Monte Carlo simulation code is developed for the ICRF (ion cyclotron range of frequencies) heating in helical systems, which takes into account finite beta effects, complicated orbits of high energetic particles, Coulomb collisions, and interactions between the particles and the applied waves. The code is used to investigate the ICRF minority heating in the Large Helical Device. The configuration of the magnetic fields changes significantly due to finite beta effects in the Large Helical Device. The resonance layer position is found to be crucial to the heating efficiency as the plasma beta increases. When the strength of the resonance magnetic field is set to the value at the magnetic axis, the higher heat efficiency is obtained and no clear difference of the heat efficiency due to the finite beta effects is found at the high ICRF wave power region. However the radial profile of the transferred power to majority ions and electrons from minority ions changes by the deformation of the trapped particle orbits due to the finite beta effects. The heat efficiency is improved if the radial electric field, E(r), is positive (E(r) is directed radially outward) and it is also improved by supplying He-3 minority ions rather than proton minority ions.
- Publication:
-
Unknown
- Pub Date:
- October 1993
- Bibcode:
- 1993mcss.rept.....M
- Keywords:
-
- Collisional Plasmas;
- Computerized Simulation;
- Coulomb Collisions;
- Cyclotron Resonance Devices;
- Electron Cyclotron Heating;
- Helical Flow;
- Ion Cyclotron Radiation;
- Minority Carriers;
- Monte Carlo Method;
- Radio Frequency Heating;
- Trapped Particles;
- Cyclotron Frequency;
- Cyclotron Resonance;
- Elastic Deformation;
- Electric Fields;
- Electrons;
- Helium Isotopes;
- Ions;
- Magnetic Fields;
- Protons;
- Plasma Physics