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Title: Self-turbulization in cellularly unstable laminar flames
It has been suggested that a cellularly unstable laminar flame, which is freely propagating in unbounded space, can accelerate and evolve into a turbulent flame with the neighbouring flow exhibiting the basic characteristics of turbulence. Famously known as self-turbulization , this conceptual transition in the flow regime, which arises from local interactions between the propagating wrinkled flamefront and the flow, is critical in extreme events such as the deflagration-to-detonation transition (DDT) leading to supernova explosions. Recognizing that such a transition in the flow regime has not been conclusively demonstrated through experiments, in this work, we present experimental measurements of flow characteristics of flame-generated ‘turbulence’ for expanding cellular laminar flames. The energy spectra of such ‘turbulence’ at different stages of cellular instability are analysed. A subsequent scaling analysis points out that the observed energy spectra are driven by the fractal topology of the cellularly unstable flamefront.  more » « less
Award ID(s):
1827287
PAR ID:
10272377
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Fluid Mechanics
Volume:
917
ISSN:
0022-1120
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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