This chapter is devoted to hydrodynamic instabilities. Internal confinement fusion (ICF) capsule implosions are inherently unstable. In particular, the Rayleigh-Taylor instability (RTI) developing at the beam accelerated capsule outer surface tends to destroy the imploding shell, while the deceleration-phase RTI occurring at the inner surface of the stagnating capsule hinders the formation of a central hot spot. Control of this instability is a major challenge facing ICF. Richtmyer-Meshkov (RMI) and Kelvin-Helmholtz (KHI) instabilities also occur in ICF. Starting from basic theory, the instability linear theory is developed in much detail, including the stabilizing effect of ablation on RTI (ablative stabilization). The resulting dispersion relation is then applied to actual ICF implosions, deriving the admissible levels of non-uniformity in capsule make and implosion drive. The nonlinear growth of bubbles and spikes, including turbulent mixing are also described.
Keywords: internal confinement fusion, Rayleigh-Taylor instability, Richtmyer-Meshkov instability, Kelvin-Helmholtz instability, instability linear theory, instability dispersion relation, deceleration-phase RTI, ablative stabilization, bubbles and spikes, turbulent mixing
Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.
If you think you should have access to this title, please contact your librarian.