点火延迟时间对粉尘最大爆炸压力测定影响的研究

根据粉尘云形成时颗粒分散及沉降的时间效应,指出目前国际通行的球型爆炸装置采用固定点火延迟时间测定粉尘最大爆炸压力的方法具有不确定性,并以煤粉为介质在20 L标准爆炸球装置上进行系列爆炸实验,研究装置点火延迟时间对粉尘爆炸压力的影响。结果表明:点火延迟时间对粉尘爆炸压力测定有十分显著的影响,不同粒径粉尘的最大爆炸压力有不同点火延迟时间,目前仅以气相湍流度所确定的固定点火延迟时间下,所测粉尘最大爆炸压力可能严重偏离实际。

Effect of Ignition Delay Time on Measurement of Maximum Explosion Pressure of Dusts

Based on the variations of particle dispersion and sedimentation with time during the dust cloud formation,the paper points out that the internationally accepted method that uses fixed ignition delay time to measure the maximum dust explosion pressure through a spherical vessel,is of uncertainty.To investigate the effect of ignition delay time on the measurement of dust explosion pressure,a series of explosion experiments were carried out in a 20 liter spherical vessel with coal dust.The results show that the ignition delay time has a significant effect on the measured values of explosion pressure and,to obtain the maximum explosion pressure of the coal dusts with different average diameters,different ignition delay time is required.Under the fixed ignition delay time internationally accepted in dust explosion experiment,the measured maximum explosion pressure may largely deviate from the actual values.