Direct numerical simulations of type Ia supernovae flames II: The Rayleigh-Taylor instability

Journal Article · Mon Jan 12 00:00:00 EST 2004 · Astrophysical Journal

DOI:https://doi.org/10.1086/420841· OSTI ID:841916

Bell, J B; Day, M S; Rendleman, C A; Woosley, S E; Zingale, M

A Type Ia supernova explosion likely begins as a nuclear runaway near the center of a carbon-oxygen white dwarf. The outward propagating flame is unstable to the Landau-Darrieus, Rayleigh-Taylor, and Kelvin-Helmholtz instabilities, which serve to accelerate it to a large fraction of the speed of sound. We investigate the Rayleigh-Taylor unstable flame at the transition from the flamelet regime to the distributed-burning regime, around densities of 10e7 gm/cc, through detailed, fully resolved simulations. A low Mach number, adaptive mesh hydrodynamics code is used to achieve the necessary resolution and long time scales. As the density is varied, we see a fundamental change in the character of the burning--at the low end of the density range the Rayleigh-Taylor instability dominates the burning, whereas at the high end the burning suppresses the instability. In all cases, significant acceleration of the flame is observed, limited only by the size of the domain we are able to study. We discuss the implications of these results on the potential for a deflagration to detonation transition.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Director. Office of Science. Office of Computational and Technology Research. Mathematics Information and Computational Sciences Division, Supernova Science Center/UCSC Contract DE-FC02-01ER41176 and DE-AC05-00OR22725; National Aeronautics and Space Administration Award NAG5-12036, National Science Foundation MRI Grant AST-0079757 (US)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 841916
• Report Number(s): LBNL-54300; R&D Project: K11001; TRN: US0503009
• Journal Information: Astrophysical Journal, Vol. 608, Issue pt.1; Other Information: Submitted to Astrophysical Journal; Volume 608, Part 1; Journal Publication Date: 06/20/2004; PBD: 12 Jan 2004
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCELERATION
EXPLOSIONS
FLAMES
HYDRODYNAMICS
INSTABILITY
MACH NUMBER
RAYLEIGH-TAYLOR INSTABILITY
RESOLUTION
SUPERNOVAE
VELOCITY
SUPERNOVAE: GENERAL WHITE DWARFS HYDRODYNAMICS NUCLEAR REACTIONS NUCLEOSYNTHESIS ABUNDANCES CONDUCTION METHODS: NU MERICAL