障碍物结构对预混火焰压力发展的影响

本文针对不同的可燃气混合物,研究了由于障碍物引起的火焰加速而导致的管内压力上升现象。在实验中,使用了三种不同形状的障碍物,同时改变障碍物的间距W和阻塞比BR。结果表明,障碍物的存在对管内压力的影响是十分巨大的,即使是较小的阻塞面积,也能导致压力大幅度上升。在障碍物阻塞比BR=0.5、障碍物间距约等于管道内径(W/D≈1)时,管内的峰值压力达到最大值。本实验所用的三种障碍物产生的管内峰值压力并不相同,以园环型的障碍物产生的压力最高,这说明,存在某一种最优化的障碍物,在相同的阻塞比条件下,该障碍物能最大地提高管内的峰值压力。

INFLUENCE OF OBSTACLE CONFIGURATIONS ON OVERPRESSURE DEVELOPMENT IN PREMIXED FLAME

An investigation of overpressure development due to flame acceleration induced by obstacles has been studied with various gas mixtures. The experiments have been carried out with three different shapes of obstacles by changing their spaces W and blockage ratio BR. It was observed that the obstacle plays a dramatic role on the overpressure development in the tube, even relatively small blockage area leading to a high increase in the overpressure . The peak overpressure reaches the top value when the blockage ratio is about 0.5 and the space of obstruction corresponds to the inner diameter of tube. The peak overpressures produced by three obstacles are different from to another, where the overpressure induced by orifice is head and shoulders. Thus it can be referred that there exists an optimum obstacle under which the maximum peak overpressure may be obtained.