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Related papers: Distributed Flames in Type Ia Supernovae

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We review the astrophysical modeling of type Ia supernova explosions and describe numerical methods to implement numerical simulations of these events. Some results of such simulations are discussed.

Astrophysics · Physics 2007-05-23 F. K. Roepke , W. Hillebrandt

Although the evolution of premixed flames in turbulence has been frequently studied, it is not well understood how small flames interact with large-scale turbulent flow motion. Since this question is of practical importance for the…

Fluid Dynamics · Physics 2020-02-04 Tobias Falkenstein , Seongwon Kang , Heinz Pitsch

The scaling of turbulent premixed flames is typically described by correlations derived for unity-Lewis-number fuels. However, their validity for hydrogen (H$_{2}$) remains uncertain due to the thermodiffusive effects associated with its…

Large-eddy simulations (LES) of a planar turbulent lean hydrogen-air jet flame at Re = 11000 are performed using a tabulated flamelet model based on mixture-averaged diffusion that incorporates detailed transport, including differential and…

Large-scale three-dimensional numerical simulations of the deflagration stage of a thermonuclear supernova explosion show the formation and evolution of a highly convoluted turbulent flame in a gravitational field of an expanding…

Astrophysics · Physics 2009-11-07 V. N. Gamezo , A. M. Khokhlov , E. S. Oran , A. Y. Chtchelkanova , R. O. Rosenberg

Thermal-diffusional pulsation behaviors in planar as well as outwardly and inwardly propagating white dwarf carbon flames are systematically studied. In the 1D numerical simulation, the asymptotic degenerate equation of state and simplified…

High Energy Astrophysical Phenomena · Physics 2017-05-31 Guangzheng Xing , Yibo Zhao , Mikhail Modestov , Cheng Zhou , Yang Gao , Chung K. Law

Preferential diffusion plays a critical role in the evolution of lean premixed hydrogen flames, influencing flame surface corrugation and overall flame behavior. Simulating such flames with tabulated chemistry (TC) methods remains…

The structure of the deflagration burning front in type Ia supernovae is considered. The parameters of the flame are obtained: its normal velocity and thickness. The results are in good agreement with the previous works of different…

High Energy Astrophysical Phenomena · Physics 2015-03-20 S. I. Glazyrin , S. I. Blinnikov , A. D. Dolgov

A space-filling, low blockage fractal grid is used as a novel turbulence generator in a premixed turbulent combustion experiment. In contrast to the power law decay of a standard turbulence grid, the downstream turbulence intensity of the…

Deflagration-to-detonation transition (DDT) can occur in environments ranging from experimental and industrial systems to astrophysical thermonuclear (type Ia) supernovae explosions. Substantial progress has been made in explaining the…

High Energy Astrophysical Phenomena · Physics 2011-08-01 Alexei Y. Poludnenko , Thomas A. Gardiner , Elaine S. Oran

Given the need to develop zero-carbon combustors for power and aircraft engine applications, $S_d$ of a turbulent premixed flame, especially for H$_2$-air, is of immediate interest. The present study investigates 3D DNS cases of premixed…

We analyze the statistical properties of the turbulent velocity field in the deflagration model for Type Ia supernovae. In particular, we consider the question of whether turbulence is isotropic and consistent with the Kolmogorov theory at…

Solar and Stellar Astrophysics · Physics 2011-02-11 F. Ciaraldi-Schoolmann , W. Schmidt , J. C. Niemeyer , F. K. Roepke , W. Hillebrandt

We study the nucleation and growth of flame fronts in slow combustion. This is modeled by a set of reaction-diffusion equations for the temperature field, coupled to a background of reactants and augmented by a term describing random…

Statistical Mechanics · Physics 2015-06-25 Mikko Karttunen , Nikolas Provatas , Tapio Ala-Nissila , Martin Grant

The burning regimes encountered by laminar deflagrations and ZND detonations propagating through helium-rich compositions in the presence of buoyancy-driven turbulence are analyzed. Particular attention is given to models of X-ray bursts…

Astrophysics · Physics 2009-10-31 F. X. Timmes , J. C. Niemeyer

Gibson scaling and related properties of flame-surface geometry in turbulent premixed combustion are demonstrated using a novel computational model, Deterministic Turbulent Mixing (DTM). In DTM, turbulent advection is represented by a…

Astrophysics · Physics 2007-05-23 J. C. Niemeyer , A. R. Kerstein

Implementing multicomponent diffusion models in numerical combustion studies is computationally expensive; to reduce cost, numerical simulations commonly use mixture-averaged diffusion treatments or simpler models. However, the accuracy and…

Fluid Dynamics · Physics 2020-10-19 Aaron J. Fillo , Jason Schlup , Guillaume Blanquart , Kyle E. Niemeyer

Propagation of premixed flames having thick reaction zones in rapidly-varying, small-scale, zero-mean, spatio-temporal periodic flows is considered. Techniques of large activation energy asymptotics and homogenization theory are used to…

Fluid Dynamics · Physics 2024-07-01 Prabakaran Rajamanickam , Joel Daou

We continue to investigate two-dimensional laterally propagating flames in type I X-ray bursts using fully compressible hydrodynamics simulations. In the current study we relax previous approximations where we artificially boosted the…

High Energy Astrophysical Phenomena · Physics 2021-05-12 A. Harpole , N. M. Ford , K. Eiden , M. Zingale , D. E. Willcox , Y. Cavecchi , M. P. Katz

In this paper we investigate the acceleration of the expansion of premixed spherical flames and evolution of the cellular patterns on their surfaces. An asymptotic model is used for the simulations and a spectral numerical algorithm is…

Fluid Dynamics · Physics 2017-02-01 V. Karlin , G. Sivashinsky

Supersonic combustion plays a vital role in various applications, including scramjets, dual-mode ramjets, and pulse detonation engines. However, the flame characteristics can vary significantly, depending on the application. To model…

Fluid Dynamics · Physics 2023-06-21 Xu Zhu , Jian An , Nana Wang , Jian Zhang , Zhuyin Ren
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