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The numerical results for cryogenic direct drive targets of megajoule facilities with radiation in the second and third harmonics of a Nd laser are presented. The calculations were performed with the 1D radiation hydrodynamics code ERA with the laser light absorption model that takes into account stimulated Brillouin scattering (SBS), generation of fast electrons in the processes of two-plasmon decay (TPD), and stimulated Raman scattering (SRS). The verification of the developed models was carried out on the basis of the comparison with experiments performed at the OMEGA and NIF facilities. The ignition margin (WQ) of nonuniform fusion targets with an allowance for energy losses due to radiation transfer and heat conduction from the hot spot was the objective of the target optimization. The calculations showed that SBS and target heating by fast electrons generated in TPD and SRS fatally reduce WQ of targets with a CH ablator for the megajoule laser with wavelength λ = 0.53 µm. The possibilities of decreasing these effects by replacing a CH ablator with a glass ablator and reducing the laser intensity upon increasing the target aspect ratio are considered. However, in both cases, WQ remains substantially below unity for the laser with wavelength λ = 0.53 µm. The ignition margin increases by a factor of ∼2 upon transition from the second to the third harmonic of a Nd laser. A glass ablator almost eliminates fast electrons in calculation with the laser wavelength λ = 0.35 µm. In this case, if SBS is reduced by a factor of 3–4 via shifting the laser emission lines in the neighboring channels by Δμ ≈ 10–20 A, the ignition margin WQ ∼ 2 and a fusion energy yield of ∼50 MJ are obtained in the 1D calculation for a laser energy of ∼2 MJ and the third harmonic of a Nd laser.

1D ERA code allows to simulate the kinetic of ionization and nonequilibrium radiation transfer in line and continua. This code is expanded to account the processes of ions ionization and excitation in the field of laser radiation. For the descriptions of the processes the wave equation is solved. The results of calculations of X-ray yield at the irradiation of Al plate by picosecond laser pulse at intensity of 1016−1017 W/cm2 are presented.

The results of 1D-ERA and 2D-TICR, 2D-OMEGA codes calculations of compression and burn of indirect-driven targets for the thermonuclear ignition and Hybrid Nuclear-Fusion Reactor are presented.

The results of the ICF indirect‐driven targets optimization performed by ZARYA/ERA code for a better insight into the requirements imposed on both target designs and hohlraum drive temperature to gain the ignition with laser of minimum power are presented. Two modification of cryogenic shell targets for hohlraum drive temperatures in the range of 0.25–0.38 keV are proposed for the ignition. The 500 TW lasers are needed to perform such investigations.

The results of the computation analysis of the turbulent mixing in the direct and indirect‐driven shell targets are presented. The simulation were carried out by TURLINA‐code based on phenomenological mixing model. The effects of the mixing are studied numerically for the SOKOL‐laser experiments and for the indirect‐driven targets. The comparison of the TURLINA‐code simulations with the SOKOL experimental X‐ray picture gives the evidence for reduction of turbulent mixing at the ablation front in experiments with shell targets. The estimates of the initial roughness and the effect of ablation‐stabilization influence on the turbulent mixing and neutron yield from DT‐filled glass microballoon are carried out. The allowable compression asymmetry for thermonuclear ignition is discussed.

A mathematical model and an implicit method of numerical modelling are described for the physical processes in micro-targets, irradiated by a laser pulse. The efficiency of the method is illustrated by the computation of model problems.