Construction of substantially different solutions of an inverse problem for a toroidal plasma equilibrium equation
Tóm tắt
The paper is devoted to the reconstruction of the current density in toroidal plasma, using experimentally measured data. The toroidal current density is characterized by two functions in the right-hand side of the Grad-Shafranov equation which, together with the poloidal flux, is to be deter-mined. The question about the uniqueness of the solution of the inverse problem was usually not addressed in the numerical methods developed over the past few decades. However, the theoretical study of this question for simplified models showed the possibility of the existence of substantially different solutions. For a correct understanding of the physical properties of a pulse it is necessary to analyze all possible solutions of the inverse problem in its physically correct formulation. This formulation is presented in the paper. A new numerical method for determining all substantially different solutions of the inverse problem is proposed. Examples of the existence of such solutions are constructed for plasma parameters which are close to experimental.
Tài liệu tham khảo
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