20L近球形容器中微米级铝粉的爆炸特性

采用20 L近球形粉尘爆炸实验系统，探究微米级铝粉在不同点火延迟时间、粉尘粒径及粉尘浓度下的爆炸特性规律。结果表明:当点火延迟时间在20~120 ms范围内，铝粉最大爆炸压力和最大爆炸压力上升速率先增大后减小，随铝粉粒径增大，最佳点火延迟时间增大；在任一点火延迟时间下，粒径大于8.12 μm的铝粉最大爆炸压力随粉尘粒径的减小呈增大的变化趋势；粒径大于8.12 μm的铝粉，在80~440 g/m3粉尘浓度范围内，铝粉最大爆炸压力和最大爆炸压力上升速率先增大后减小，且铝粉粒径越小，对应的最猛烈爆炸粉尘浓度越低。

Explosion characteristics of micro-sized aluminum dust in 20 L spherical vessel

In order to investigate explosion characteristics of micro-sized aluminum dust, a series of experiments were carried out to reveal the influences of ignition delay time, dust particle size and dust concentration on explosion parameters of aluminum dust using a 20 L nearly spherical dust explosion experimental system. The results show that:when the ignition delay time was within 20-120 ms, the maximum explosion pressure and maximum rate of pressure rise of aluminum dust initially increased but then decreased, the optimum ignition delay time increased with increasing particle size. The maximum explosion pressure of aluminum dust with particle size greater than 8.12 μm increased with decreasing particle size. Moreover, when the particle size is greater than 8.12 μm and the dust concentration range is 80-440 g/m3, the maximum explosion pressure and pressure rise rate of aluminum dust increased at beginning and then decreased, in addition, the smaller the dust particle size, the lower the dust concentration corresponding to the most violent explosion.