We perform 2D ignition capsule implosion simulation by a 2D multi-group radiation diffusion hydrodynamic code LARED-S which simultaneously simulates radiation drive asymmetry and outer surface roughness. Implosion flow field shows large-amplitude spikes and bubbles as well as a significant low-mode shell areal density asymmetry. Amplitudes of modes generated by mode coupling are in good agreement with analytic mode coupling equation until perturbation amplitude of fundamental mode L24 is greater than nonlinear saturation amplitude. In deceleration phase, perturbation growth is in strong nonlinear phase, and strong mode coupling effects broaden mode distribution. High-density spikes are bent by vortex flow. Mode coupling degrades greatly implosion performance, leading to ignition failure. Further simulations of mode coupling between low-mode drive asymmetry and capsule surface roughness is critical for understanding influences of hydrodynamic instabilities on ignition capsule implosion.

High-foot high-adiabat implosion simulations of ICF ignition capsules are performed with one-dimensional multi-group radiation transport hydrodynamic code RDMG and two-dimensional few-group radiation diffusion hydrodynamic code LARED-S. Compared with low-adiabat implosion, high-foot implosions improve significantly stability of ablation front and ablator-fuel interface by increasing radiation drive temperature of the foot, leading to great reduction of hydrodynamic instability growth and hot-spot mix. Meanwhile, high-foot implosion decrease DT fuel compression. Final compression density and areal density of the main fuel at stagnation are decreased, causing lower neutron yield. A better stability of high-foot high-adiabat implosion is obtained at cost of reducing DT fuel compression.

We introduce an ignition hohlraum 2D-simulation design method with 2D code.A design sequence,in which X-rays drive tempetature is tuned before P² asymmetry,is put forward.Details in designing laser power is studied.It indicates that control of P² asymmetry during trough pulse limits the maximum of filling gas density and expansion of capsule ablator can be restrained by longer drive pulse.An ignition hohlraum 2D-simulation design is given.

In order to untangle serious distortion in a hohlraum for ICF (Inertial Confinement Fusion),a nine-point rezone strategy is developed.The scheme is approximate to an elliptic or a parabolic equation,and preserves spherical symmetry.The scheme includes several forms of the nine-point rezone scheme according to different requirement in practical problems.The ALE (Arbitrary Lagrangian-Eulerian) method is used in code LARED-H. Suitable results for a hohlraum is illustrated.

For Rayleigh-Taylor instability experiments diagnosed by backlight X-ray image on a moderate power laser facility, several kinds of backlighter materials and thier X-ray spectra have been studied theoretically. The simulated results show that it is possible to produce about 2 kev X-ray backlight using a several hundred Jaules 2ω₀ laser.

The paper presents the main processes of physics and the outline of the computational program related laser X-ray conversion, gives the typical pictures and numerical results. Based on numerical simulations, the laws of some important properies of physics are obtained, the results estimated by the scaling lasw are in comparison with the measurement values, they are coincident each other on quantitative tendency and quantitative results.