During the tokamak operation, variation of the stored energy can cause internal perturbations of the plasma. These perturbations may develop into large-scale vertical movement of the whole column for the vertically el...During the tokamak operation, variation of the stored energy can cause internal perturbations of the plasma. These perturbations may develop into large-scale vertical movement of the whole column for the vertically elon- gated tokamak, eventually generating the hot vertical displacement event (VIDE,). It will cause considerable damage to the machine. In this work, the hot VDE process due to stored energy perturbations is investigated by a mature non-linear time-evolution code DINA. The influence on the vertical instability, the displacement direction and the electromagnetic loads on in-vessel components during the hot VDE are analyzed. It is shown that a larger perturbation leads to faster development of the vertical instability. Meanwhile the variation of the Shafranov shift, due to the energy change, is related to the VDE direction. The vertical electromagnetic force on the vacuum vessel and the halo current flowing in the divertor baffle become larger in the case of VDE moving towards the X point.展开更多
We point out that a suitable scale of time for the Schrödinger perturbation process is a closed line having rather a circular and not a conventional straight-linear character. A circular nature of the scale c...We point out that a suitable scale of time for the Schrödinger perturbation process is a closed line having rather a circular and not a conventional straight-linear character. A circular nature of the scale concerns especially the time associated with a particular order N of the perturbation energy which provides us with a full number of the perturbation terms predicted by Huby and Tong. On the other hand, a change of the order N—connected with an increased number of the special time points considered on the scale—requires a progressive character of time. A classification of the perturbation terms is done with the aid of the time-point contractions present on a scale characteristic for each N. This selection of terms can be simplified by a partition procedure of the integer numbers representing N-1. The detailed calculations are performed for the perturbation energy of orders N=7 and N=8 .展开更多
In this article, the risk process perturbed by diffusion under interest force is considered, the continuity and twice continuous differentiability for Фδ(u,w) are discussed,the Feller expression and the integro-di...In this article, the risk process perturbed by diffusion under interest force is considered, the continuity and twice continuous differentiability for Фδ(u,w) are discussed,the Feller expression and the integro-differential equation satisfied by Фδ (u ,w) are derived. Finally, the decomposition of Фδ(u,w) is discussed, and some properties of each decomposed part of Фδ(u,w) are obtained. The results can be reduced to some ones in Gerber and Landry's,Tsai and Willmot's, and Wang's works by letting parameter δ and (or) a be zero.展开更多
基金Supported by the Chinese ITER Plan Project Foundation under Grant Nos 2013GB113001 and 2015GB105001the National Natural Science Foundation of China under Grant No 11575056
文摘During the tokamak operation, variation of the stored energy can cause internal perturbations of the plasma. These perturbations may develop into large-scale vertical movement of the whole column for the vertically elon- gated tokamak, eventually generating the hot vertical displacement event (VIDE,). It will cause considerable damage to the machine. In this work, the hot VDE process due to stored energy perturbations is investigated by a mature non-linear time-evolution code DINA. The influence on the vertical instability, the displacement direction and the electromagnetic loads on in-vessel components during the hot VDE are analyzed. It is shown that a larger perturbation leads to faster development of the vertical instability. Meanwhile the variation of the Shafranov shift, due to the energy change, is related to the VDE direction. The vertical electromagnetic force on the vacuum vessel and the halo current flowing in the divertor baffle become larger in the case of VDE moving towards the X point.
文摘We point out that a suitable scale of time for the Schrödinger perturbation process is a closed line having rather a circular and not a conventional straight-linear character. A circular nature of the scale concerns especially the time associated with a particular order N of the perturbation energy which provides us with a full number of the perturbation terms predicted by Huby and Tong. On the other hand, a change of the order N—connected with an increased number of the special time points considered on the scale—requires a progressive character of time. A classification of the perturbation terms is done with the aid of the time-point contractions present on a scale characteristic for each N. This selection of terms can be simplified by a partition procedure of the integer numbers representing N-1. The detailed calculations are performed for the perturbation energy of orders N=7 and N=8 .
文摘In this article, the risk process perturbed by diffusion under interest force is considered, the continuity and twice continuous differentiability for Фδ(u,w) are discussed,the Feller expression and the integro-differential equation satisfied by Фδ (u ,w) are derived. Finally, the decomposition of Фδ(u,w) is discussed, and some properties of each decomposed part of Фδ(u,w) are obtained. The results can be reduced to some ones in Gerber and Landry's,Tsai and Willmot's, and Wang's works by letting parameter δ and (or) a be zero.