| Автор | F. Alladio |
| Автор | P. Micozzi |
| Дата выпуска | 1997-12-01 |
| dc.description | Magnetic measurements alone on spherical tori should allow a very good separation of the poloidal beta beta <sub>p</sub>, from the internal self-inductance l<sub>i</sub>/2 and should even permit an accurate estimate of the current density j<sub>phi </sub> profile. However, the reduced space allowed for magnetic sensors near the central conductor in a spherical tokamak, and the possibility of producing flux core spheromak configurations without a central conductor, could imply that magnetic probes are not present in the cavity of the spherical torus. The fluxes and fields of a variety of calculated spherical torus configurations, all endowed with a single or double null separatrix, are analysed in terms of spherical multipolar moments obtained from simulated magnetic measurements located only upon a sphere surrounding the spherical plasma. The solution to the problem of the absence of magnetic measurements in the cavity of the spherical torus is to fix from non-magnetic measurements (e.g., spectroscopy) the plasma inboard boundary r<sub>in</sub> on the equatorial plane. This constraint is added to the constraints of matching the spherical multipolar expansion in an iterative solution of the Grad-Shafranov equation, on the basis of a spherical geometry. The convergence of the spherical reconstructive equilibrium code is extremely fast and gives an error on the total plasma current I<sub>p</sub> of less than 1% at an aspect ratio A=1.2, an error on the position of the plasma boundary of less than 2% of the radius of the plasma sphere, an error on beta <sub>p</sub> of at most 15% and, finally, the j<sub>phi </sub> profile is extremely well reconstructed in peaked, flat and even hollow cases. The effect of an uncertainty +or- delta r<sub>in</sub> upon the spectroscopic identification of the plasma inboard boundary on the equatorial plane r<sub>in</sub> is assessed |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | Reconstruction of spherical torus equilibria in absence of magnetic measurements in the central cavity |
| Тип | paper |
| DOI | 10.1088/0029-5515/37/12/I08 |
| Electronic ISSN | 1741-4326 |
| Print ISSN | 0029-5515 |
| Журнал | Nuclear Fusion |
| Том | 37 |
| Первая страница | 1759 |
| Последняя страница | 1774 |
| Аффилиация | F. Alladio; Centro Ricerche Energia Frascati, ENEA, Rome, Italy |
| Аффилиация | P. Micozzi; Centro Ricerche Energia Frascati, ENEA, Rome, Italy |
| Выпуск | 12 |
