高温熔融铝液柱遇水蒸汽爆炸的压力及固体产物分布实验研究

Experimental study on steam explosion pressure and solid product distribution of high-temperature molten aluminum liquid column in contact with cooling water

为揭示高温熔融铝液柱遇水作用后的蒸汽爆炸压力及固体产物分布特性,开展了不同温度和下落高度条件下的熔融铝液柱与水相互作用的实验研究。通过对爆炸后固体产物粒径的统计分析,获得了不同条件下的产物粒径分布图。将熔融铝与水相互作用分为未爆炸、局部爆炸和完全爆炸3种类型。当熔融铝质量为200g时,发生完全爆炸的超压在100kPa~200kPa之间,而局部爆炸的超压在30kPa~60kPa之间。基于Kelvin-Helmholtz不稳定性的临界波长和临界韦伯数理论对维持熔融液滴稳定状态的最小直径进行计算,发现液柱的温度与下落高度对碎化过程有明显的影响作用。通过对熔融铝液柱与水相互作用现象、产物及压力峰值的分析,发现熔融铝温度、铝液柱的下落高度对过程中发生碎化及爆炸的结果有显著影响,当铝液温度大于1500℃或下落高度大于90cm时,熔融铝液柱发生碎化和蒸汽爆炸的概率会显著增加。随着碎化及爆炸程度的加剧,金属产物的直径也呈变小趋势,当温度高于1500℃时,粉末状的产物明显增多。

In order to reveal the explosion intensity and characteristics of solid product distribution,the interaction between high-temperature molten aluminum column and water is studied.The effects of temperature and falling height of molten aluminum column on the fragmentation and steam explosion of molten aluminum in contact with cooling water are analyzed.The distribution diagram of product particle size is obtained by analyzing the particle size of products under different experimental conditions.The interaction between molten aluminum and water can be divided into three types:unexploded,local explosion and complete explosion.When the mass of molten aluminum is 200g,the peak overpressure of complete explosion is in the range of 100kPa-200kPa,while the peak overpressure of local explosion is in the range of 30kPa-60kPa.The fragmentation mechanism of interaction between molten aluminum and water is discussed based upon the critical wavelength of Kelvin-Helmholtz instability and the theory of critical Weber number.According to the phenomenon,product and overpressure peak of interaction between molten aluminum column and water,it is found that the temperature and falling height of molten aluminum column have a significant impact on the fragmentation and explosion in the process.When the temperature of molten aluminum is larger than 1500℃or the falling height is higher than 90cm,the probability of fragmentation and steam explosion of molten aluminum column increase significantly.With an increase in the explosion intensity of fragmentation,the diameter of solid products decreases,and the proportion of powder and fine granular products increase significantly when the temperature of molten aluminum is larger than 1500℃.