In tokamak experiments, various MHD instabilities usually co-exist and interact with fast particles. It can cause significant particle transport loss, pose damage to the first wall, leading discharge quench in tokamak. Therefore, understanding physical mechanism of caused by is a crucial but urgently solved issue for steady-state long pulse operation future reactor-graded devices. Based on expe...

We present the results of fast time scale plasma control simulations for the proposed Korea Superconducting Tokamak Advanced Research (KSTAR) tokamak. Here, the fast plasma control includes stabilization of the vertical instability and rapid radial position control. As a simulation tool, we use the tokamak simulation code (TSC). We evaluate the power supply requirements for both the vertical an...

Light reflections are one of the main and often underestimated issues of plasma emissivity reconstruction in visible light spectral range. Metallic and other specular components of tokamak generate systematic errors in the optical measurements that could lead to wrong interpretation of data. Our analysis is performed at data from the tokamak COMPASS. It is a D-shaped tokamak with specular metal...

In the present study, a series of experiments were performed to study collisions runaway electrons in Damavand tokamak by imaging hard x-ray radiations, as one secondary effects these electrons, using radiochromic films. For experiments, GAFCHROMIC™EBT2 dosimetry films selected due their high resolution capability. These instruments installed two strip and screen structures for one- two-dimensi...

Electron cyclotron resonance heating (ECRH), as a highly efficient and controllable heating tool, has been widely used in tokamak magnetic confinement devices [1]. Usually, the EC power can be injected as narrow Gaussian beams, which gives rise to highly localized power deposition. Consequently, ECRH and electron cyclotron current drive (ECCD) have been expolied to an ideal candidate for local ...

Tokamak is a promising device for using nuclear fusion energy, and the triggering of power supply has characteristics extreme asymmetry drastic instantaneous change, which bring spectrum-rich harmonics to DC side supply, threatening operational safety device. Although harmonic analysis method already exists, however, it still problem cumbersome inaccurate calculation when oriented systems with ...

Highly relativistic runaway electrons are of great concern in the area of fusion energy research, since their presence in tokamak plasmas have the potential to hinder the successful and stable operation of the device, and potentially cause severe structural damage. In this thesis, runaway electron generation dynamics is investigated using the newly developed efficient computational tool CODE. A...