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Updated: Nov 12, 2025
10:29
Experimental Methodology for Estimation of Local Heat Fluxes and Burning Rates in Steady Laminar Boundary Layer Diffusion Flames
Published on: June 1, 2016
12.1K
Complex network analysis of the gravity effect on premixed flames propagating in a Hele-Shaw cell
Yuji Nomi1, Hiroshi Gotoda, Shuya Kandani
1Department of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika, Tokyo 125-8585, Japan.
Physical Review. E
|March 19, 2021
Summary
Gravity significantly increases flame front randomness in Hele-Shaw cells, especially with negative Rayleigh numbers. Complex network analysis reveals this chaos is driven by Rayleigh-Taylor instability and large-scale wrinkles.
Area of Science:
- Physics
- Fluid Dynamics
- Complex Systems
Background:
- Flame front dynamics are crucial in combustion and fluid instabilities.
- Hele-Shaw cells provide a controlled environment to study 2D fluid phenomena.
- Complex network theory offers novel methods for analyzing dynamic systems.
Purpose of the Study:
- To investigate the influence of gravity on spatiotemporal flame front dynamics.
- To quantify the randomness and chaos in flame propagation using network analysis.
- To understand the role of Rayleigh-Taylor instability in flame front behavior.
Main Methods:
- Utilizing a Hele-Shaw cell to simulate flame propagation.
- Applying complex network analysis, including flame front and transition network entropies.
- Varying gravitational levels and analyzing the normalized Rayleigh number (Ra).
Main Results:
- Flame front randomness increases with gravity for negative Ra.
- Two network entropies clearly identify increased randomness.
- Rayleigh-Taylor instability drives large-scale wrinkles, leading to chaos at Ra<0.
Conclusions:
- Gravity significantly impacts flame front dynamics in Hele-Shaw cells.
- Complex network metrics effectively capture the increase in randomness.
- The study highlights the link between instability, chaos, and flame front behavior.
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