A method of flame stabilization using thermo-acoustic self-excited sound oscillation is demonstrated and the flame stabilization mechanism is investigated by a simplified standing acoustic fields generated by two loud speakers and a resonance tube. V-shaped flame which is formed in low flow velocity fields is employed for the mechanism investigation. The minimum sound pressures for flame stabilization are determined experimentally with fuel lean and rich flames. The temperature is measured by thin filament pyrometry which gives correlated color temperature of distribution along the flame glowing SiC fibers. As a result, it is found that the outer edge of the fuel rich V-shaped flame moves to the upstream by applying the acoustic field and the flame is stabilized without any flame holder. The fuel lean flame does not deform significantly and extinguishes by sound. In the fuel rich condition, the temperature of the diffusion flame near the outer edge is found to increase by sound. Considering above, the partial premixed structure of the outer edge plays an essential role on this flame holding.
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