Rayleigh-Taylor instability on high gain target for heavy ion beam fusion
A numerical analysis has been performed on the stability of targets designed to produce fusion energy gains close to 100, when irradiated with an appropriate heavy ion beam. To attain this, a high-Z radiation screen is necessary, in order to screen the D-T fuel from the radiation emitted by the surrounding hot material. Since the opacity of high-Z material is only weakly density dependent, it has been possible to consider only targets with shields made of lead at the density of a solid or at the density of the adjacent external material. The behaviour of both these kinds of targets had been studied by introducing a small spatial non-uniformity on the external surface of the lead shielding. Targets with low-density shields have also been tested with a beam intensity perturbation. Since density gradients are very sharp and ablation is practically absent, these implosions have been found to be Rayleigh-Taylor unstable. The evolution has been followed in the non-linear regime, since the full hydrodynamical-radiative model with a non-linear heavy ion energy deposition and mesh correction was used.
Bibliographic Reference: Report: RT/NUCL/90/36 EN (1991) 20 pp.
Availability: Available from Servizio Studi e Documentazione, ENEA, Centro Ricerche Energia Frascati, C.P. 65-00044 Frascati, Roma (IT)
Record Number: 199210218 / Last updated on: 1994-12-02
Original language: en
Available languages: en