新型微乳化柴油抛撒和云雾爆炸实验及其抑爆性能评估

为掌握新型微乳化柴油的抑爆性能和机理,开展了-10#柴油、普通微乳化柴油和新型微乳化柴油抛撒和云雾爆炸实验。采用灰色关联分析法,对柴油样品云雾爆炸火球的表面最高温度时的平均温度、高温(高于1 273.15 K)持续时间、火球最大截面积、火球辐射度等特征参数进行定量计算并评估其爆炸威力,又运用液体燃料抛撒和成像系统,研究柴油样品在激波及其高速气流作用下的抛撒雾化现象及其抑爆机理。结果表明:新型微乳化柴油的抛撒云雾径向扩展半径和云雾爆炸火球特征参数均明显小于-10#柴油、普通微乳化柴油,如在含水质量分数为5%的乳化柴油中分别添加质量分数为0.2%和0.4%的高分子聚合物防雾剂,形成的新型微乳化柴油的火球表面最高平均温度比-10#柴油分别低296.90和336.90 K,高温持续时间比-10#柴油分别少94和234 ms;火球最大截面积也分别只有-10#柴油的60.10%、53.53%;新型微乳化柴油的爆炸威力最小,抑爆性能最好,其次是普通微乳化柴油和-10#柴油;微乳化柴油的水分质量分数在15%以下时,多增加10%的水与添加0.2%防雾剂的抑爆效果相当;新型微乳化柴油抑爆性能较好的主要原因是柴油中添加防雾剂使其液滴黏弹性增大,在高速气流剪切作用不易破碎、雾化,液滴分散效果差。

Experimental study of dispersal and cloud explosion of a new micro-emulsified diesel fuel and its explosion suppression performance assessment

To find out about the explosion suppression performance and mechanism of a new microemulsified diesel fuel,we carried out experiments on the dispersal and cloud explosion of.10#diesel fuel,ordinary micro-emulsified diesel fuel and new micro-emulsified diesel fuel.We calculated the average temperature at the maximum surface temperature,the high temperature duration(longer than 1 273.15 K),the maximum cross-sectional area and the radiant emittance of the cloud explosion fireballs of diesel fuel samples and evaluated them using the grey correlation analysis method and studied the dispersal atomization phenomena and explosion suppression mechanisms of the diesel fuel samples under the shock wave and high-speed airflow using the liquid fuel dispersal and imaging system.The results showed that the cloud radial expansion radius and the characteristic parameters of the explosion fireball of the new microemulsified diesel fuel were obviously lower than those of.10#diesel fuel and ordinary micro-emulsified diesel fuel.For example,the maximum surface mean temperatures of the fireballs of the new microemulsified diesel fuel samples made up by mixing 0.2%or 0.4%high polymer antifogging agents into the fuel containing 5%water were 296.90 and 336.90 K lower than those of.10#diesel fuel.Their high temperature duration is shorter by 94 and 234 ms respectively.The maximum cross-sectional areas of their fireballs were only 60.10%and 53.53%that of.10#diesel fuel respectively.The explosion power of the new micro-emulsified diesel fuel was the lowest and the explosion suppression performance was the best,followed by ordinary micro-emulsified diesel fuel and.10#diesel fuel.When the water mass fraction of the micro-emulsified diesel fuel was less than 15%,the explosion suppression effect of the micro-emulsified diesel fuel with an addition of 10%water was equivalent to that with an addition of 0.2%antifogging agents.The key for this better explosion suppression performance was that the viscosity and elasticity of the droplets increased due to the addition of antifogging agents to the diesel fuel,and that the droplets were not apt to be broken and atomized under the shearing action of high-speed airflow,and the dispersion of the droplets was not effective.