This paper generalizes the single-shell Kidder＇s self-similar solution to the double-shell one with a discontinuity in density across the interface. An isentropic implosion model is constructed to study the Rayleigh-...This paper generalizes the single-shell Kidder＇s self-similar solution to the double-shell one with a discontinuity in density across the interface. An isentropic implosion model is constructed to study the Rayleigh-Taylor instability for the implosion compression. A Godunov-type method in the Lagrangian coordinates is used to compute the one-dimensional Euler equation with the initial and boundary conditions for the double-shell Kidder＇s self-similar solution in spherical geometry. Numerical results are obtained to validate the double-shell implosion model. By programming and using the linear perturbation codes, a linear stability analysis on the Rayleigh-Taylor instability for the double-shell isentropic implosion model is performed. It is found that, when the initial perturbation is concentrated much closer to the interface of the two shells, or when the spherical wave number becomes much smaller, the modal radius of the interface grows much faster, i.e., more unstable. In addition, from the spatial point of view for the compressibility effect on the perturbation evolution, the compressibility of the outer shell has a destabilization effect on the Rayleigh-Taylor instability, while the compressibility of the inner shell has a stabilization effect.展开更多
The double-cone ignition scheme is a promising novel ignition method,which is expected to greatly save the driver energy and enhance the robustness of the implosion process.In this paper,ablation of the inner surface ...The double-cone ignition scheme is a promising novel ignition method,which is expected to greatly save the driver energy and enhance the robustness of the implosion process.In this paper,ablation of the inner surface of the cone by the hard X-ray from coronal Au plasma is studied via radiation hydrodynamics simulations.It is found that the X-ray ablation of the inner wall will form strong pre-plasma,which will significantly affect the implosion process and cause the Au plasma to mix with the fuel,leading to ignition failure.The radiation and pre-ablation intensities in the system are estimated,and the evolutions of areal density,ion temperature and the distribution of Au ions are analysed.In addition,the mixing of Au in CH at collision is quantified.Then,a scheme to reduce the X-ray pre-ablation by replacing the gold cone with a tungsten cone is proposed,showing that it is effective in reducing high-Z mixing and improving collision results.展开更多
基金Project supported by the NSAF Joint Fund set up by the National Natural Science Foundation of China and the Chinese Academy of Engineering Physics (CAEP)(Nos. 10676005, 10676004, and10676120)the National Natural Science Foundation of China (No. 10702011)+1 种基金the Natural Science Foundation of CAEP (No. 2007B09001)the Scientific Research Foundation for Returned Overseas Chinese Scholars of Ministry of Education of China
文摘This paper generalizes the single-shell Kidder＇s self-similar solution to the double-shell one with a discontinuity in density across the interface. An isentropic implosion model is constructed to study the Rayleigh-Taylor instability for the implosion compression. A Godunov-type method in the Lagrangian coordinates is used to compute the one-dimensional Euler equation with the initial and boundary conditions for the double-shell Kidder＇s self-similar solution in spherical geometry. Numerical results are obtained to validate the double-shell implosion model. By programming and using the linear perturbation codes, a linear stability analysis on the Rayleigh-Taylor instability for the double-shell isentropic implosion model is performed. It is found that, when the initial perturbation is concentrated much closer to the interface of the two shells, or when the spherical wave number becomes much smaller, the modal radius of the interface grows much faster, i.e., more unstable. In addition, from the spatial point of view for the compressibility effect on the perturbation evolution, the compressibility of the outer shell has a destabilization effect on the Rayleigh-Taylor instability, while the compressibility of the inner shell has a stabilization effect.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA25050200 and XDA25010100)the National Natural Science Foundation of China(Grant Nos.12175309,12475252,12275356 and 12075317)the Defense Industrial Technology Development Program(Grant No.CKYS2023212807).
文摘The double-cone ignition scheme is a promising novel ignition method,which is expected to greatly save the driver energy and enhance the robustness of the implosion process.In this paper,ablation of the inner surface of the cone by the hard X-ray from coronal Au plasma is studied via radiation hydrodynamics simulations.It is found that the X-ray ablation of the inner wall will form strong pre-plasma,which will significantly affect the implosion process and cause the Au plasma to mix with the fuel,leading to ignition failure.The radiation and pre-ablation intensities in the system are estimated,and the evolutions of areal density,ion temperature and the distribution of Au ions are analysed.In addition,the mixing of Au in CH at collision is quantified.Then,a scheme to reduce the X-ray pre-ablation by replacing the gold cone with a tungsten cone is proposed,showing that it is effective in reducing high-Z mixing and improving collision results.
