【摘要】 为研究无约束条件下甲烷（CH₄）/空气（air）预混气体的燃爆特性，以乳胶气球为反应容器开展了甲烷爆炸实验，结合Chemkin模拟和改进的比色测温技术，研究了不同当量比下甲烷/空气预混气体的火焰传播速度、爆炸超压及温度场分布等特征以及静置时间对预混气体燃爆特性的影响。实验结果表明：甲烷/空气预混气体的爆炸火焰传播速度呈振荡分布，当量比为0.83、1.06、1.30和1.55时的平均火焰传播速度分别为1.554m·s^-1、2.122m·s^-1、1.892m·s^-1和1.428m·s^-1;峰值超压随当量比的增加呈先增大后减小的趋势，当量比为1.06时基元反应CH₃·+O₂?O·+CH₃O·的敏感性系数最大，从而加速了生成二氧化碳（CO₂）的链反应，使得燃烧化学反应最彻底，峰值超压值最大；静置时间对火焰传播速度和爆炸峰值压力影响显著，最佳静置时间为6min;随着当量比的增大，爆炸火焰的平均温度呈现先增大后减小的趋势，当量比为1.06时，平均温度达到最大值2263K。更多还原

【Abstract】 In order to study the deflagration characteristics of premixed methane/air under the unconstrained condition, the gas explosion tests were carried out with latex balloons as the reaction vessels, and the flame propagation velocity, explosion overpressure, and temperature field distribution of methane/air premixed gas with different equivalent ratios and standing time was studied by combining the Chemkin simulation and the improved two-colour pyrometer. The experimental results show that the flame propagation velocity oscillated before the balloon was ruptured, and the average flame propagation velocity of the four equivalent ratios of 0.83, 1.06, 1.30 and 1.55 are 1.554m·s^-1, 2.122m·s^-1, 1.892m·s^-1 and 1.428m·s^-1, respectively. When the equivalent ratio is 1.06, the elementary reaction of CH₃·+O₂?O·+CH₃O· has the largest sensitivity coefficient, which promotes the chain reaction of CO₂ formation, and the chemical reaction is the most radical, and the peak overpressure value is the largest. The standing time has a significant effect on flame propagation velocity and peak explosion pressure, and these parameters reach the maximum values when the standing time is set as 6min. With the increase of the equivalent ratio, the average flame temperature of premixed methane/air increases at first and then decreases, and the maximum value of is 2263K when the equivalent ratio is 1.06.更多还原