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Small-scale Interaction of Turbulence with Thermonuclear Flames in Type Ia Supernovae

J. C. Niemeyer·W. K. Bushe·G. R. Ruetsch
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Abstract

Microscopic turbulence-flame interactions of thermonuclear fusion flames occuring in Type Ia Supernovae were studied by means of incompressible direct numerical simulations with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its Prandtl number, Pr << 1, and laminar flame speed, S_L. We find that if S_L ~ u', where u' is the rms amplitude of turbulent velocity fluctuations, the local flame propagation speed does not significantly deviate from S_L even in the presence of velocity fluctuations on scales below the laminar flame thickness. This result is interpreted in the context of subgrid-scale modeling of supernova explosions and the mechanism for deflagration-detonation-transitions.

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J. C. Niemeyer, W. K. Bushe, G. R. Ruetsch. 1999-05-07. Small-scale Interaction of Turbulence with Thermonuclear Flames in Type Ia Supernovae. https://doi.org/10.1086/307813

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