Conveners
H&CD session
- Eva Belonohy (EUROfusion Consortium, Institute of Plasma Physics of the Czech Academy of Sciences)
H&CD session
- Eva Belonohy (EUROfusion Consortium, Institute of Plasma Physics of the Czech Academy of Sciences)
H&CD session
- damian king (UKAEA)
H&CD session
- damian king (UKAEA)
Reaching the milestone of > 1GJ of heating energy was an important demonstration of the physical and technical capabilities of the W7-X stellarator. This milestone was achieved using exclusively ECRH power, which was also a challenge for the ECRH system itself and the handling of ECRH-specific loads on the components in the vessel. This is especially true for high density operation and not...
The objective of WEST experiments is to master long-pulse operation (1000 s) while exposing actively cooled ITER-like tungsten divertor to power fluxes up to 10 MW/m2. To increase the margins to reach H-Mode regime and to control W-impurities in the plasma core, the WEST ECRH system is under major upgrade with the objective to reach the capabilities of injecting 3 MW during up to 1000 s at a...
After the successful integration of passive active multijunction (PAM) launcher in ADITYA-U tokamak, the lower hybrid current drive (LHCD) experiments with PAM launcher is conducted in ADITYA-U tokamak. The PAM launcher, designed to launch up to 250kW of rf power at 3.7 GHz, for one second, was successfully installed on radial port#5 of the tokamak. It was validated for UHV compatibility (10-9...
Lower hybrid current drive (LHCD) has proven to be one of the most efficient methods to sustain long pulse plasma operation in tokamak. In order to sustain good LHW (lower hybrid wave) -plasma coupling required for long pulse plasma, it is the first time that the coupling feedback control is designed and realized in EAST through PID (Proportion Integration Differentiation) method by choosing...
Abstract:
The objective of WEST experiments is to master long-pulse operation (1000 s) while exposing the actively cooled ITER-grade tungsten divertor to power fluxes up to 10 MW/m2. The reliability and performance of the Lower Hybrid Current Drive (LHCD) system are critical for the success of long pulse operation on WEST as it allows to drive significant non-inductive current in the...
The experiments on plasma initiation performed in EAST with the electron cyclotron wave (ECW) pre-ionization and assisted start-up have demonstrated that ITER can produce plasma initiation in a low toroidal electric field (<0.3V/m). The parameter domain of breakdown is significantly extended towards higher prefill gas pressure. The effect of ECW injection timing, power, toroidal injection...
Neutral Beam Injection (NBI) requires high particle energies if one of its aims is to contribute to current drive in large fusion tokamaks. For example, 1 MeV D is foreseen for the ITER NBI. At such energies, the NBI must be based on a source of negative hydrogen ions (N-NBI) due to their higher neutralization efficiency of up to 60% in a gas neutralizer. Negative hydrogen ions are produced on...
While Neutral Beam Injection (NBI) with beam energies in excess of about 100 keV/amu (e.g. on ITER, JT-60SA, DTT) requires sources for negative ions (“N-NBI”), positive-ion-based (“P-NBI”) systems have attracted renewed interest for smaller long-pulse fusion devices such as volumetric neutron sources (VNS). In these devices, like for instance the tokamak-based VNS currently studied by...
Tokamak-based fusion neutron sources (FNS) can effectively address the fuel problems of nuclear energy and future fusion power plants operation [1]. FNS primary mission is testing technological systems being exposed to intense neutron flux and evaluation of relevant effects in materials and structural components designed for future nuclear reactors, fusion-fission and pure thermonuclear...
Neutral beam injector is one of the essential devices for KSTAR long pulse operation. It contributes to sustain the non-inductive plasma current in long pulse tokamak operation as well as to obtain the high ion temperature operation mode in KSTAR. In a viewpoint of long pulse superconducting tokamak, it has been playing a very challenging pioneering work for future tokamak reactor since its...
It has been observed that lost fast ions in NBI plasma will hit the first wall of the device to affect the long pulse steady-state operation. The fast-ion loss mechanisms include prompt loss, ripple loss and resonant loss due to MHD instabilities[1]. Also, MHD instabilities are closely related to fast-ion beta βf [2-3]. In our research, we focused on the simulation and experimental...
Ion cyclotron resonance heating (ICRH) has been a dependable tool for sturdy and long pulse plasma heating with high RF power of several megawatts. However, low ICRH antenna coupling efficiency, high temperature of antenna limiter and Faraday Screen (FS) and MHD instabilities have limited high-power and long-pulse operation of the system. To increase ICRH antenna coupling efficiency and...
