A simple and direct theoretical method has been proposed to investigate the so- called ion-banana-orbit-width （IBW） effect on the bootstrap current in the region of magnetic islands generated by the neoclassical tea...A simple and direct theoretical method has been proposed to investigate the so- called ion-banana-orbit-width （IBW） effect on the bootstrap current in the region of magnetic islands generated by the neoclassical tearing mode （NTM）. The result shows that, when the IBW approaches the island width, the （ion） bootstrap current can be partly restored inside the island while the pressure profile is flattened. This can lead to the reduction of the bootstrap current drive on the NTM. The strength of the IBW effect on the NTM is related to the safety factor and the inverse aspect ratio on the rational surface.展开更多
In the previous analytical description of the neoclassical polarization current effect on the neoclassical tearing modes （NTMs）, it is usually assumed that the magnetic island is much larger than the finite-ion-bana...In the previous analytical description of the neoclassical polarization current effect on the neoclassical tearing modes （NTMs）, it is usually assumed that the magnetic island is much larger than the finite-ion-banana-width （FBW）. This assumption is questionable when the experimentally observed seed island width of the NTMs is comparable to the FBW. We introduce a simple and direct theoretical method to investigate the FBW effect on the neoclassical polarization contribution to the NTM evolution in collisional plasmas. The results show that, the FBW effect can strongly modify the neoclassical polarization current profile near the island separatrix, and thus weaken its probably stabilizing effect on the NTMs.展开更多
基金supported by the National Magnetic Confinement Fusion Science Program of China(Nos.2011GB105002 and 2010GB106006)National Natural Science Foundation of China(No.11175057)
文摘A simple and direct theoretical method has been proposed to investigate the so- called ion-banana-orbit-width （IBW） effect on the bootstrap current in the region of magnetic islands generated by the neoclassical tearing mode （NTM）. The result shows that, when the IBW approaches the island width, the （ion） bootstrap current can be partly restored inside the island while the pressure profile is flattened. This can lead to the reduction of the bootstrap current drive on the NTM. The strength of the IBW effect on the NTM is related to the safety factor and the inverse aspect ratio on the rational surface.
基金supported by the National Magnetic Confinement Fusion Science Program of China (Nos.2011GB105002,2014GB107001 and 2014GB124004)National Natural Science Foundation of China(Nos.11175057 and 11275061)
文摘In the previous analytical description of the neoclassical polarization current effect on the neoclassical tearing modes （NTMs）, it is usually assumed that the magnetic island is much larger than the finite-ion-banana-width （FBW）. This assumption is questionable when the experimentally observed seed island width of the NTMs is comparable to the FBW. We introduce a simple and direct theoretical method to investigate the FBW effect on the neoclassical polarization contribution to the NTM evolution in collisional plasmas. The results show that, the FBW effect can strongly modify the neoclassical polarization current profile near the island separatrix, and thus weaken its probably stabilizing effect on the NTMs.
