燃料浓度对可燃气云爆炸影响的实验研究与数值模拟

以0．02mm厚度的聚乙烯薄膜为约束物，进行了半径0．5m的半球形乙炔／空气气云爆炸实验。结果表明，在100mJ弱点火条件下，乙炔的爆炸界限(乙炔的质量分数)由1．5％～82．2％缩小到5．3％～17．8％，乙炔的最危险质量分数为13．3％。建立了描述可燃气云爆炸的数学模型，并采用SIMPLE算法对模型进行求解，得到了不同燃料质量分数的爆炸超压分布。计算结果与实验值相比较，最大相对偏差为10．11％。对甲烷／空气、乙烯／空气、乙炔／空气等气云爆炸威力进行了预测，当处于最危险质量分数时，大体积的3种气云爆炸均可造成建筑物的损坏，而随着质量分数偏离最危险质量分数，破坏能力随之降低。

EXPERIMENTAL AND SIMULATION STUDY OF THE EFFECT OF FUEL CONCENTRATION ON FLAMMABLE VAPOR CLOUD EXPLOSION

Taking 0.02 mm polyethylene film as the confinement, experiments on explosion of hemispheric ethyne/air cloud of (0.5m) radius were conducted. The results showed that explosion range of ethyne shrunk to 5.7%-17.6% from 1.5%-82.2% when weak ignition was used and the most dangerous mass fraction was (13.3%). A mathematics model of flammable vapor explosion was established and SIMPLE algorithm was used to solve the model. The overpressure distribution of different fuel mass fractions was obtained. Compared with experimental data, the maximum relative deviation based on calculated value was (10.11%). In addition, the explosion power of methane/air, ethane/air and ethyne/air were forecasted. Buildings can be damaged in the explosions of all these three kinds of larger volume clouds when the most dangerous mass fraction was adopted. However, the explosion power will decrease gradually as fuel mass fraction deviates from the most dangerous mass fraction.