Title: Flickering Buoyant Diffusion Flames in Weakly Rotatory Flows

Time: 2022-11-10            10：00~11：30

Venue: Institute for Energy Research, 1517 + Tencent Meeting (182-322-583)

Organizer: Institute for Energy Research

Abstract:

Flickering buoyant diffusion methane flames in weakly rotatory flows were computationally and theoretically investigated. The prominent computational finding is that the flicker frequency nonlinearly increases with the rotational intensity number R (up to 0.24), which measures the relative importance of the rotational speed compared with the methane jet speed. This finding is consistent with the previous experimental observations that flame flicker is enhanced by rotatory flows within a certain extent. Based on the vortex-dynamical understanding of flickering flames that the flame flicker is caused by the periodic shedding of buoyancy-induced toroidal vortices, we formulated a scaling theory for flickering buoyant diffusion flames in weakly rotatory flows. In physics, the externally rotatory flow enhances the radial pressure gradient around the flame, and the significant baroclinic effect contributes an additional source for the growth of toroidal vortices so that their periodic shedding is faster.