Showing papers by "Stefano Atzeni published in 1984"
TL;DR: In this paper, an initial transient phase and the self-heating stage, burn in propagated mainly by α-particle transport, while the burning region is cooled at comparable rates by heat conduction and hydrodynamic expansion.
Abstract: Ignition of initially isobaric D-T plasmas, triggered by a hot spot, surrounded by denser, cold fuel, is studied both analytically and numerically. It the conditions for self-heating of the not spot are met, then a burn wave propagates, at first through deflagration driven by α-particles, and eventually through detonation. After an initial transient phase and the self-heating stage, burn in propagated mainly by α-particle transport, while the burning region is cooled at comparable rates by heat conduction and hydrodynamic expansion. The whole process is described by means of three dimensionless quantities (related to α-particle production, thermal conductivity and α-particle transport, respectively), and, as suggested by ID numerical results, an ignition criterion is given in terms of two of them. Examples of applications show, its usefulness in target design. A condition for burn propagation is also derived.
42 citations
TL;DR: In this paper, a simple model is used to evaluate the reactor potentiality of direct-drive laser fusion shell targets, irradiated by unshaped laser pulses of an energy lower than a few mega-joules.
Abstract: A simple model is used to evaluate the reactor potentiality of direct-drive laser fusion shell targets, irradiated by unshaped laser pulses of an energy lower than a few mega-joules. For single-shell targets a narrow design window in the relevant parameter space exists, which allows for a gain G > 200. Long wavelengths (λ > 2 µm), small aspect ratios (ADT < 30) and small D-T masses (MDT < 3 mg) are excluded. For double-shell targets these constraints are somewhat relaxed; the relevant results agree with preliminary 1-D simulations.
3 citations