Study on Compression of ICF Fuel in Rocket Model

Abstract

Compression of Inertial Confinement Fusion (ICF) fuel as required by Lawson Criterion has been of immense value in ICF studies. In this work, the order of compression has been studied on Rocket Model because a high-order reaction force responsible for compression may be seen to act as a rocket motion. It has been seen that the order of compression of lighter fuel such as D-T may be more effective if irradiated by high power Nd laser. The shocks produced as the reaction (Rocket effect) to the surface ablation generated by pulsed laser beams, compress the fuel which is estimated to be effective when the ratio of initial mass to the accelerated one is of the order of 5. The maximum achievable compression by a single strong shock is not more than 4 for a monatomic gas. For weak coalescing shocks to achieve adiabatic compression, the ablation efficiency is found to be maximum when target velocity equals nearly twice the ablation velocity. In such a case, the implosion efficiency of Rocket Model is found to be about 67 percent; neglecting heat loss.