为分析不同粉尘因密度的差异对20 L球形爆炸装置球罐内粉尘分散过程流场变量变化和点火延迟时间的影响,利用CFD数值模拟的方法,研究了3种不同密度的粉尘在球罐分散过程中湍流动能、流场速度、粉尘浓度3种流场变量在球心处的变化规律.研究结果表明:在其他条件一致的情况下,粉尘密度越小,湍流动能的峰值越小,粉尘云浓度和流场速度的峰值则越大;粉尘密度对湍流动能的增值速率没有影响,而粉尘密度越小,流场速度和粉尘浓度的增值速率越快,粉尘浓度衰减至稳定值的时间也越短.表明粉尘密度越小,点火延迟时间也越小,因此,建议铝粉点火延迟时间在50~60 ms之间,锆粉和锌粉在60~80 ms之间.%In order to analyze the influence of different dust density on the variation of the flow field variables and the ignition delay time during the dust dispersion process in the spherical tank of 20 L spherical explosive device , the CFD numerical simulation method was adopted to study the variation laws of three flow field variables including the turbulence kinetic ener -gy, flow field velocity and dust concentration at the center of the spherical tank for three types of dust with different density during the dispersion process in the spherical tank .The results showed that when the other conditions were the same , the smaller the dust density , the smaller the peak value of the turbulent kinetic energy , the greater the peak values of the dust cloud concentration and the flow field velocity .The dust density had no effect on the increasing rate of the turbulence kinetic energy , while the smaller the dust density , the larger the increasing rate of the flow field velocity and dust concentration , and the shorter the time that the dust concentration decreased to the stable value .It showed that the smaller the dust density , the smaller the ignition delay time , so the ignition delay time of aluminum dust was recommended between 50-60 ms, and those of zirconium dust and zinc dust were recommended between 60-80 ms.
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