雾化气流脉动下乙醇喷雾旋流火焰特性

针对雾化气流脉动条件下乙醇喷雾旋流非稳态燃烧问题,开展了不同雾化流量下乙醇喷雾旋流火焰对雾化气流脉动响应特性的实验研究,揭示了不同脉动频率和脉宽时长下火焰长度和抬升高度的响应特性,获得了乙醇喷雾燃烧在雾化气流脉动条件下的火焰结构、温度分布等动态规律.结果表明:随着雾化流量增加,旋流火焰由附着演化为抬升;此外,雾化气流脉...

Characteristics of ethanol spray flame under flow pulsation in swirl burner

The unsteady combustion behaviors of an ethanol spray flame perturbed by pulsations of different atomizing gaseous flows were investigated experimentally.By varying the atomizing gas flow rate，the responses of flame length and lift-off height to different pulsation frequencies and durations，as well as the flame structure and temperature distribution under flow pulsations，were examined.The results showed that the spray flame changed from attachment to lift-off as the atomizing flow-rate increased.The atomizing process of liquid ethanol was significantly affected by the flow pulsation，resulting in oscillations of flame length and lift-off height at the same frequency.Under the same atomizing flow rate，the average flame length of attached flame and lifting height of lift-off flame increased.The droplet velocity，size and spatial distribution dominating the mixing of ethanol spray and oxidant were directly affected by flow pulsation，resulting in an enhancement of heat-release，while the effect of pulsating frequency was less significant.