Pseudo-three-dimensional simulation on stability of thin shell target implosion

Pseudo-three-dimensional simulation method has been developed to analyze implosion stability of thin shell target in inertial confinement fusion. Nonlinear motion of a thin spherical surface driven by the pressure simulates the implosion of a shell target filled with fuel gas. The simulation shows that acceleration and deceleration of the shell give rise to the Rayleigh–Taylor instability and the instability prevents the target from being compressed uniformly. The results of the simulation show how the maximum volume compression ratio and breakup time of the target depend upon the initial perturbation amplitude. The new simulation scheme has also been applied to another shape of closed surfaces. The implosion phenomenon of the surface of torus is shown as an example. The toroidal target implosion is found to be more stable against the Rayleigh–Taylor instability than that of spherical targets.