70th Annual Meeting of the APS Division of Fluid Dynamics (November 19, 2017 — November 21, 2017)

V0087: Implosion driven turbulence in a spherical mixing layer

Authors

• Ismael Boureima, University of North Carolina at Charlotte
• Praveen Ramaprabhu, University of North Carolina at Charlotte

DOI: https://doi.org/10.1103/APS.DFD.2017.GFM.V0087

This video describes shock-driven turbulent mixing in the context of a spherical implosion. The simulations are intended as an idealization of the conditions that exist in Inertial Confinement Fusion (ICF). In such applications, the interface between the fuel and the outer shell material is susceptible to the Richtmyer-Meshkov instability and turbulent mixing which can jeopardize the fusion process. We describe the behavior of a multimode interface that degenerates in to a turbulent mixing layer when subjected to a spherical implosion. Results are presented from 3D numerical simulations performed using the astrophysical FLASH [1] code, while the underlying problem description is adopted from Youngs and Williams [2]. During the implosion, perturbations at the interface are subjected to growth due to the Richtmyer-Meshkov instability, the Rayleigh-Taylor instability, as well as Bell-Plesset effects.

 

[1] Fryxell, B., Olson, K., Ricker, P., Timmes, F X., Zingale, M., Lamb, D. Q., Macneice, P., Rosner, R., Truran, J. W., and Tufo, H., 2000, “Flash: An Adaptive Mesh Hydrodynamics Code for Modeling Astrophysical Thermonuclear Flashes,” Astrophys J. Suppl. Ser., 131(1), pp.273–334.

[2] Youngs, D. L., and Williams, R. J. R., 2008, “Turbulent Mixing in Spherical Implosions,” Int. J. Num. Meth. Fluids, 56(8), pp. 1597–1603