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arXiv · 2202.06719

Turbulent flame speed based on the mass flow rate: theory and DNS

Swetaprovo Chaudhuri·Bruno Savard
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Abstract

Starting with an integral formulation of mass flow rate through an ensemble of isotherms constituting a statistically planar, turbulent premixed flame, a scaling for the corresponding turbulent flame speed is derived without invoking Damk{\"o}hler's hypotheses. Major approximations and interim results are validated using a large Karlovitz number, unity Lewis number, Direct Numerical Simulation (DNS) dataset of n-heptane/air mixture, computed with reduced chemistry. A new length scale quantifying the fluctuation distance of the isotherms within the premixed flame structure is introduced.

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Swetaprovo Chaudhuri, Bruno Savard. 2022-02-14. Turbulent flame speed based on the mass flow rate: theory and DNS. https://arxiv.org/abs/2202.06719

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