The Numerical Simulation Of Compact Toroids Acceleration With The Radiation Hydrodynamics Model

The compact toroids (CT) have a wide range of use, such as: as a pulse x-ray source or a fusion driver etc. The research of CT acceleration is the foundation of the CT application studies.The radiation hydrodynamics(RHD) model which established by derivating the loop equation of acceleration current and introducing the RHD equations is used to calculate the CT acceleration in this paper. The expressions of state, coupling terms, diffusion terms are given. The Runge-Kutta method is used to calculate the acceleration current. On the base of Lagrange coordinate, the set of RHD equations is solved by implicit iterative algorithm and the technique dealing with the boundary condition is described. The split tricks are used to avoid much coupling in treating with the set due to the numerous equations. Two-dimensional code has been developed and the computing results of accelerating the CT in a straight coaxial gun are carried out. Those results which include CT kinetic energy, CT speed, radiated energy loss, the temperatures of electrons, ions and radiation field will provide an initial data for further studies of the CT application.Under the condition of LTE approximation, the calculation methods of mean ionization state and radiative opacities are presented due to the requirements of dealing with the set of RHD equations. By comparing the results of Al and Cu plasma opacity which calculated for testifying the method on computing the radiative opacity with that of SESAME Library, good agreements have been found. In order for the mean ionization states and radiative opacities of Ar to be conveniently used in the simulation of RHD equations, the calculated data are fitting to be the function of electron temperatures and densities.The factors related to acceleration efficiency are discussed with the whole acceleration model owing to the needs of providing the best initial condition for RHD model. CT mass, the length of accelerator, the radius proportion of coaxial gun, the acceleration capacitance are included in those factors. On one hand, the contrast and the initial parameters of the more accurate model are provided, one the other hand, the references of designing the accelerator are supplied by the whole acceleration model results.