不同湍流状态对乙醇蒸气近爆炸下限火焰传播过程的影响

Effect of Turbulence on Flame Propagation Process of Ethanol Vapor Approached Lower Explosion Limit

利用FRTA爆炸极限测试仪和高速摄影仪,研究了湍流对乙醇蒸气火焰传播过程的影响.采用控制测试容器内搅拌子的转速获得不同湍流强度的方法,试验研究了乙醇蒸气在不同湍流强度下的火焰传播速度.研究结果表明:球形火焰前锋阵面在宏观静止状态时较为平滑,在湍流作用下球形火焰前锋的褶皱加强,火焰形状逐渐变为椭球形,火焰传播速度也随着湍流的增强而逐渐增大.当转速为0rad/s时,火焰传播的速度为1.3m/s,当转速为400rad/s时,火焰传播速度达到2.3m/s.

The effect of turbulence on the flame propagation process of ethanol vapor was studied by FRTA explosion limit tester and high speed photometer. In order to obtain different turbulence intensity, the speed of stir unit into FRTA was controlled. The flame propagation speed of ethanol vapor with different turbulence intensity was experiential studied. The results show that spherical flame forward front was smooth in till state. The spherical flame front produced wrinkles when turbulence appeared and flame shape to become ellipse shape. The flame propagation speed increased with the enhancement of turbulence intensity. When the rotate speed of stir unit into FRTA was 0 tad/s, the flame propagation speed was 1. 3m/s. When the rotate speed was 400 tad/s, the speed of the flame propagation was 2. 3 m/s.