Laminar jet methane/air diffusion flame shapes and radiation of low air velocity coflow in microgravity

In this study, a set of experiments were carried out in micro- and normal gravities to study the flame shape and oscillation of co-flow laminar diffusion ethylene and propane flames. The experimental results show that in microgravity, the flame length and width are larger than those under normal gravity, and the ratio of flame length to width is lower than that in normal gravity. The flame length and width decrease seriously with the increasing co-flow air velocity in microgravity, while they are almost unaffected by the co-flow air velocity in normal gravity. The flame oscillation is not experimentally noticeable in microgravity. In normal gravity, it is found that the flame oscillation frequency increases linearly with the volume flow rate of co-flow air. The flame oscillation is fully suppressed when the air co-flow velocity exceeds the critical velocity. And, the critical air co-flow velocity increases with the initial fuel flow velocity.

Shape and Oscillation of Ethylene and Propane Laminar Diffusion Flames in Micro- and Normal Gravities

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Z. Dai

Papers

Shapes of soot-free laminar coflowing jet diffusion flames