TYPE Ia SUPERNOVAE: CALCULATIONS OF TURBULENT FLAMES USING THE LINEAR EDDY MODEL
Abstract
The nature of carbon burning flames in Type Ia supernovae is explored as they interact with Kolmogorov turbulence. Onedimensional calculations using the Linear Eddy Model of Kerstein elucidate three regimes of turbulent burning. In the simplest case, largescale turbulence folds and deforms thin laminar flamelets to produce a flame brush with a total burning rate given approximately by the speed of turbulent fluctuations on the integral scale, U{sub L} , This is the regime where the supernova explosion begins and where most of its predetonation burning occurs. As the density declines, turbulence starts to tear the individual flamelets, making broader structures that move faster. For a brief time, these turbulent flamelets are still narrow compared to their spacing and the concept of a flame brush moving with an overall speed of U{sub L} remains valid. However, the typical width of the individual flamelets, which is given by the condition that their turnover time equals their burning time, continues to increase as the density declines. Eventually, mixed regions almost as large as the integral scale itself are transiently formed. At that point, a transition to detonation can occur. The conditions for such a transition are explored numerically and it is estimatedmore »
 Authors:

 Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
 Combustion Research Facility, Sandia National Laboratory, Livermore, CA 94551 (United States)
 Center for Computational Science and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)
 Publication Date:
 OSTI Identifier:
 21367447
 Resource Type:
 Journal Article
 Journal Name:
 Astrophysical Journal
 Additional Journal Information:
 Journal Volume: 704; Journal Issue: 1; Other Information: DOI: 10.1088/0004637X/704/1/255; Journal ID: ISSN 0004637X
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CARBON BURNING; EXPLOSIONS; FLAMES; HYDRODYNAMICS; INTEGRALS; ONEDIMENSIONAL CALCULATIONS; SHOCK WAVES; SUPERNOVAE; TURBULENCE; VELOCITY; BINARY STARS; ERUPTIVE VARIABLE STARS; FLUID MECHANICS; MECHANICS; STAR BURNING; STARS; VARIABLE STARS
Citation Formats
Woosley, S E, Kerstein, A R, Sankaran, V, Aspden, A J, and Roepke, F. K., Email: woosley@ucolick.or, Email: arkerst@sandia.go, Email: AJAspden@lbl.go, Email: fritz@mpaGarching.mpg.d. TYPE Ia SUPERNOVAE: CALCULATIONS OF TURBULENT FLAMES USING THE LINEAR EDDY MODEL. United States: N. p., 2009.
Web. doi:10.1088/0004637X/704/1/255.
Woosley, S E, Kerstein, A R, Sankaran, V, Aspden, A J, & Roepke, F. K., Email: woosley@ucolick.or, Email: arkerst@sandia.go, Email: AJAspden@lbl.go, Email: fritz@mpaGarching.mpg.d. TYPE Ia SUPERNOVAE: CALCULATIONS OF TURBULENT FLAMES USING THE LINEAR EDDY MODEL. United States. https://doi.org/10.1088/0004637X/704/1/255
Woosley, S E, Kerstein, A R, Sankaran, V, Aspden, A J, and Roepke, F. K., Email: woosley@ucolick.or, Email: arkerst@sandia.go, Email: AJAspden@lbl.go, Email: fritz@mpaGarching.mpg.d. Sat .
"TYPE Ia SUPERNOVAE: CALCULATIONS OF TURBULENT FLAMES USING THE LINEAR EDDY MODEL". United States. https://doi.org/10.1088/0004637X/704/1/255.
@article{osti_21367447,
title = {TYPE Ia SUPERNOVAE: CALCULATIONS OF TURBULENT FLAMES USING THE LINEAR EDDY MODEL},
author = {Woosley, S E and Kerstein, A R and Sankaran, V and Aspden, A J and Roepke, F. K., Email: woosley@ucolick.or, Email: arkerst@sandia.go, Email: AJAspden@lbl.go, Email: fritz@mpaGarching.mpg.d},
abstractNote = {The nature of carbon burning flames in Type Ia supernovae is explored as they interact with Kolmogorov turbulence. Onedimensional calculations using the Linear Eddy Model of Kerstein elucidate three regimes of turbulent burning. In the simplest case, largescale turbulence folds and deforms thin laminar flamelets to produce a flame brush with a total burning rate given approximately by the speed of turbulent fluctuations on the integral scale, U{sub L} , This is the regime where the supernova explosion begins and where most of its predetonation burning occurs. As the density declines, turbulence starts to tear the individual flamelets, making broader structures that move faster. For a brief time, these turbulent flamelets are still narrow compared to their spacing and the concept of a flame brush moving with an overall speed of U{sub L} remains valid. However, the typical width of the individual flamelets, which is given by the condition that their turnover time equals their burning time, continues to increase as the density declines. Eventually, mixed regions almost as large as the integral scale itself are transiently formed. At that point, a transition to detonation can occur. The conditions for such a transition are explored numerically and it is estimated that the transition will occur for densities near 1 x 10{sup 7} g cm{sup 3}, provided the turbulent speed on the integral scale exceeds about 20% sonic. An example calculation shows the details of a detonation actually developing.},
doi = {10.1088/0004637X/704/1/255},
url = {https://www.osti.gov/biblio/21367447},
journal = {Astrophysical Journal},
issn = {0004637X},
number = 1,
volume = 704,
place = {United States},
year = {2009},
month = {10}
}