Cryogenic Targets of Shock Ignition: Modeling of Diffusive Filling with a Hydrogen Fuel

• Published in: Physics of atomic nuclei 2022-12, Vol.85 (Suppl 1), p.S90-S100
• Main Authors: Aleksandrova, I. V., Koresheva, E. R.
• Format: Article
• Language: English
• Subjects: Analysis; Aspect ratio; Deuterium; Fusion reactors; Gaseous fuels; Hydrogen; Hydrogen as fuel; Hydrogen fuels; Ignition; Inertial confinement fusion; Inertial fusion (reactor); Laser-plasma interactions; Liquid fuels; Mass production; Modelling; Moving targets; Nuclear energy; Particle and Nuclear Physics; Pellet fusion; Physics; Physics and Astronomy; Research projects; Tritium
• ISSN: 1063-7788; 1562-692X
• DOI: 10.1134/S1063778822130026

Currently, within the International Atomic Energy Agency (IAEA), the coordination research project “Pathways to Energy from Inertial Fusion: Materials Research and Technology Development” has been started [1]. The Lebedev Physical Institute takes part in this project under contract no. 24154. The aim of the research is to develop technologies for mass production of cryogenic fuel targets of shock ignition having a low initial aspect ratio. These targets are assumed to be more hydrodynamically stable during the implosion [2, 3]. A key aspect of the research is the creation of methods and technologies that are functional in a high-repetition mode [1]. For this purpose, the Lebedev Physical Institute proposes to use a unique free-standing target (FST) method [4, 5], which works with free-standing and line-moving targets. This makes it possible to economically produce a required number of cryogenic targets and inject them at the required rate into the focus of a powerful laser facility or an inertial confinement fusion reactor. The preparatory stage before the formation of any targets is their filling with a fuel, which is deuterium (D 2 ) or deuterium–tritium mixture (D–T). In world practice, it is customary to carry out the filling stage either by diffusion of gaseous fuel through the target shell wall or by injecting liquid fuel through a thin capillary (several tens of microns) built into the shell wall. This work, for the first time, presents the results of modeling the project targets filling up to pressures of 1250 atm at 300 K for various materials of the target shell. The issues of implementation of an optimal filling procedure on the basis of a ramp filling regime with a constant pressure are discussed. It is based on a ramp filling regime with a constant pressure gradient, which allows one to avoid mechanical destruction of the targets during the entire filling cycle.