Reliable simulations of laser–target interaction on the macroscopic scale are burdened by the fact that the energy transport is very often non-local. This means that the mean-free-path of the transported species is larger than the local gradient scale lengths and transport can be no longer considered diffusive. Kinetic simulations are not a feasible option due to tremendous computational demands, limited validity of the collisional operators and inaccurate treatment of thermal radiation. This is the point where hydrodynamic codes with non-local radiation and electron heat transport based on first principles emerge. The simulation code PETE (Plasma Euler and Transport Equations) combines both of them with a laser absorption method based on the Helmholtz equation and a radiation diffusion scheme presented in this article. In the case of modelling ablation processes it can be observed that both, thermal and radiative, transport processes are strongly non-local for laser intensities of 1013 W/cm2 and above. In this paper simulations for various laser intensities and different ablator materials are presented, where the non-local and diffusive treatments of radiation transport are compared. Significant discrepancies are observed, supporting importance of non-local transport for inertial confinement fusion related studies as well as for pre-pulse generated plasma in ultra-high intensity laser–target interaction.

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The research of burnable absorber (BA) is a very important issue, due to BA influence on regulation and control of reactivity in the reactor. Burnable absorbers compensate initial excess reactivity in the reactor and thus allow longer fuel cycle with higher fuel enrichment. This paper deals with the depletion calculation of Evolutionary Power Reactor (EPR) nuclear fuel with different types of BA, and with optimization of the BA. The main objective of this paper is to calculate burnable absorber composed of 2 elements. The distribution of BA in the fuel is here assumed uniform. Based on depletion calculation, elements are divided into two groups, fast and slow BAs. Several combinations of two BA elements are then calculated based on this division. The evaluation of each BA combination is made, and the most appropriate one is selected.

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