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arXiv · 2201.01585

Vortex Interaction in Triple Flickering Buoyant Diffusion Flames

Tao Yang·Yicheng Chi·Peng Zhang
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Abstract

Triple flickering buoyant diffusion flames as a nonlinear dynamical system of coupled oscillators were computationally investigated. The four distinct dynamical modes (in-phase, death, rotation, and partial in-phase) observed in the previous candle-flame experiments were computationally reproduced for jet diffusion flames of methane. The four modes were interpreted from the perspective of vortex interaction and particularly of vorticity reconnection and vortex-induced flow. Specifically, the in-phase mode is caused by the periodic shedding of the trefoil vortex formed by the reconnection of three toroidal vortices; the death mode is due to the suppression of vortex shedding at small Reynolds numbers; the rotation mode appears as three toroidal vortices alternatively shed off with a constant phase difference; the partial in-phase model is caused by the vorticity reconnection of two toroidal vortices leaving another one shedding off in anti-phase.

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Tao Yang, Yicheng Chi, Peng Zhang. 2022-01-05. Vortex Interaction in Triple Flickering Buoyant Diffusion Flames. https://doi.org/10.1016/j.proci.2022.07.011

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