Low Mach Number Modeling of Type Ia Supernovae. II. EnergyEvolution
Abstract
The convective period leading up to a Type Ia supernova (SNIa) explosion is characterized by very low Mach number flows, requiringhydrodynamical methods wellsuited to longtime integration. We continuethe development of the low Mach number equation set for stellar scaleflows by incorporating the effects of heat release due to externalsources. Low Mach number hydrodynamics equations with a timedependentbackground state are derived, and a numerical method based on theapproximate projection formalism is presented. We demonstrate throughvalidation with a fully compressible hydrodynamics code that this lowMach number model accurately captures the expansion of the stellaratmosphere as well as the local dynamics due to external heat sources.This algorithm provides the basis for an efficient simulation tool forstudying the ignition of SNe Ia.
 Authors:
 Publication Date:
 Research Org.:
 Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
 Sponsoring Org.:
 USDOE Director. Office of Science. Advanced ScientificComputing Research
 OSTI Identifier:
 920061
 Report Number(s):
 LBNL58673Pt.II
Journal ID: ISSN 0004637X; ASJOAB; R&D Project: K11001; BnR: KJ0101010; TRN: US200822%%707
 DOE Contract Number:
 DEAC0205CH11231
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 649; Journal Issue: 2pt1; Related Information: Journal Publication Date: 10/02/2006
 Country of Publication:
 United States
 Language:
 English
 Subject:
 99 GENERAL AND MISCELLANEOUS; ALGORITHMS; EXPLOSIONS; HEAT SOURCES; HYDRODYNAMICS; IGNITION; MACH NUMBER; SIMULATION; STELLAR ATMOSPHERES; SUPERNOVAE; VALIDATION; supernovae: general white dwarfs hydrodynamics convectionmethods:numerical
Citation Formats
Almgren, Ann S., Bell, John B., Rendleman, Charles A., and Zingale,Mike. Low Mach Number Modeling of Type Ia Supernovae. II. EnergyEvolution. United States: N. p., 2006.
Web.
Almgren, Ann S., Bell, John B., Rendleman, Charles A., & Zingale,Mike. Low Mach Number Modeling of Type Ia Supernovae. II. EnergyEvolution. United States.
Almgren, Ann S., Bell, John B., Rendleman, Charles A., and Zingale,Mike. Tue .
"Low Mach Number Modeling of Type Ia Supernovae. II. EnergyEvolution". United States.
doi:. https://www.osti.gov/servlets/purl/920061.
@article{osti_920061,
title = {Low Mach Number Modeling of Type Ia Supernovae. II. EnergyEvolution},
author = {Almgren, Ann S. and Bell, John B. and Rendleman, Charles A. and Zingale,Mike},
abstractNote = {The convective period leading up to a Type Ia supernova (SNIa) explosion is characterized by very low Mach number flows, requiringhydrodynamical methods wellsuited to longtime integration. We continuethe development of the low Mach number equation set for stellar scaleflows by incorporating the effects of heat release due to externalsources. Low Mach number hydrodynamics equations with a timedependentbackground state are derived, and a numerical method based on theapproximate projection formalism is presented. We demonstrate throughvalidation with a fully compressible hydrodynamics code that this lowMach number model accurately captures the expansion of the stellaratmosphere as well as the local dynamics due to external heat sources.This algorithm provides the basis for an efficient simulation tool forstudying the ignition of SNe Ia.},
doi = {},
journal = {Astrophysical Journal},
number = 2pt1,
volume = 649,
place = {United States},
year = {Tue Mar 28 00:00:00 EST 2006},
month = {Tue Mar 28 00:00:00 EST 2006}
}

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