Turbulence topology evolution in weakly turbulent premixed flames
نویسندگان
چکیده
In turbulent premixed flames, not only the isotropy of velocity fluctuations is altered by thermal expansion effect but also dissipative structure flow field and topology are deeply influenced flame. Considering joint probability density function second third invariants gradient tensor (VGT)—or its traceless counterpart—is a classical way to deduce flows at these smallest scales. These quantities analyzed considering direct numerical simulation databases flame kernel growth in homogeneous isotropic turbulence. Two conditions turbulence–combustion interaction considered, which correspond two distinct values Bray number. The analysis VGT shows that propagating associated variations significantly modify turbulence topology. To understand this behavior as interacts with front, Lagrangian dynamics studied conditional mean rate change vectors. Special emphasis thus placed on evolution equations invariants. best authors' knowledge, first time such budgets scrutinized under combustion conditions. pressure Hessian contribution invariant transport shown be one leading-order terms evolution, making it critically important structure.
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ژورنال
عنوان ژورنال: Physics of Fluids
سال: 2021
ISSN: ['1527-2435', '1089-7666', '1070-6631']
DOI: https://doi.org/10.1063/5.0039330