气相爆炸防控始终是工业生产安全领域研究的重要课题之一，尤其多组分可燃气体爆炸涉及更为复杂的物理化学作用机制，研究其致灾成因和对应的预防与控制措施尤为重要。密闭容器内多元组分气体的爆炸与传播特性研究是这一工作的基础，可为其提供重要的理论支撑。本文以氢气、一氧化碳和甲烷为研究对象，以实验测试、理论分析和数值模拟为研究手段。主要开展三部分研究内容：首先，获取不同体积配比和添加量的氢气/一氧化碳组分影响甲烷爆炸的压力特征参数分布，掌握其影响规律；其次，揭示氢气/一氧化碳组分对甲烷爆炸传播特征的影响规律，如爆炸火焰的发展演化，冲击波与火焰阵面的耦合作用等；最后，通过基元反应动力学进程分析结合宏观爆炸特性，建立氢气/一氧化碳组分影响甲烷爆炸宏观特征与微观反应进程的内在关联。 实验中以同步进行的压力-高速摄影测试为主要手段，获取了20L爆炸罐与爆炸管道内氢气/一氧化碳影响甲烷的压力特征和火焰传播规律，运用基于“Canny”算子的边缘检测程序识别并提取了火焰锋面参数，定义了爆炸初期火焰的线性传播速度。基于爆炸进程中的热-动力学发展过程，以理论模型计算了氢气/一氧化碳影响下甲烷的气相燃爆指数、层流燃烧速度和爆炸热损失量等特性参数。利用化学反应动力学计算软件CHEMKIN Pro，以GRI-Mech 3.0详细反应机理为基础，在零维均质反应器内解析了氢气/一氧化碳影响甲烷爆炸的基元反应动力学进程，得到了混合体系主要组分和关键中间产物的含量、生成率和敏感性等动力学参数变化规律。 通过爆炸特性参数测试实验，得到了氢气/一氧化碳影响甲烷爆炸超压特性的宏观规律。60%添加量以内时，氢气/一氧化碳组分提升了7%甲烷的层流燃烧速度值，增大了体系的燃料-空气比，使混合体系的爆炸压力逐步升高至最大值，燃爆时间参数缩短至最小，燃爆指数大幅度增加；添加量的继续增大加剧了体系贫氧程度，减小了其层流燃烧速度，相应特征参数同步减小。氢气/一氧化碳对9.5%和12%甲烷的爆炸特征参数影响规律与之相似，它们的添加改变了混合体系的层流燃烧速度，继而引发宏观爆炸特性参数的变化。同等添加量下，氢气/一氧化碳组分中氢气占比越高，其对甲烷爆炸的影响越大，而一氧化碳随添加量的增大对甲烷爆炸呈现出先阻尼后促进的阶段性双重作用特征。 混合体系接近爆炸上限时，浮力作用改变了火焰传播形态，基于理想球形火焰理论的层流燃烧速度模型计算结果会出现较大误差。无量纲因子理查逊指数Ri和达姆科勒指数Da可以量化表征爆炸过程中的上浮火焰行为特征。理查逊指数大于临界值0.1时；或达姆科勒指数大于1且层流燃烧速度大于火焰上浮速率时，爆炸火焰的发展主要受到已燃区域和未燃区域的密度差引起的浮力作用。此外，体系层流燃烧速度与火焰上浮速率比值的大小决定了火焰上浮过程中的形态特征。 通过爆炸传播特征实验，获取了氢气/一氧化碳对甲烷爆炸传播特性的影响规律。在0~60%添加量范围内，氢气/一氧化碳组分促进了7%甲烷爆炸火焰传播，使其火焰锋面速度逐步增大至峰值。同等添加量下，氢气/一氧化碳气体中H2占比越高则混合体系火焰锋面速度越大。由于实验管道内爆炸传播过程中的热损失变化，一氧化碳添加后并未表现出先阻尼而后促进的阶段性特征。40%添加量以内，H2占比大于50%的氢气/一氧化碳组分提升了9.5%甲烷的火焰锋面速度；H2占比小于50%时，火焰锋面在距点火中心13.4cm~24.4cm处有小幅度提升，而在距33.8cm~44.8cm时有所减小。氢气/一氧化碳气体加剧了12%甲烷的贫氧程度，大幅减小了爆炸火焰传播速度且伴随有波动现象。 氢气/一氧化碳影响甲烷爆炸的反应动力学分析结果表明，其对甲烷爆炸的促进作用取决于关键自由基O、H和OH的生成率，从而通过OH + CH4 ⇌ CH3 +H2O，H + CH4 ⇌ CH3 + H2 和O + CH4 ⇌ OH + CH3等基元反应使甲烷脱氢，加剧了支链反应的发展。氢气/一氧化碳的添加对甲烷爆炸关键自由基的影响主要通过O + H2 ⇌ H + OH，H + O2 ⇌ O +OH，OH+ H2 ⇌ H + H2O和OH + CO ⇌ H + CO2等基元反应实现。整体而言，H2占比高的氢气/一氧化碳组分对三种关键自由基的含量变化影响更为显著。

The prevention and mitigation of gases explosion have always been the important topics in the field of industrial safety. The multi-component combustible gas explosion involves more complicated physical and chemical mechanisms, so it is particularly important to study its causes of disasters and the corresponding mitigation and control measures. The study of the explosion characteristics and propagation characteristics of multi-element combustible components in a sealed vessel is the basis of this work and can provide important theoretical support. In this paper, the combustible gases H2, CO and CH4 were taken as research medias. Experimental tests, theoretical analysis and numerical simulation were employed as the main methods. The main research objectives are as follows, firstly, obtaining the pressure parameters of CH4-Air explosion with the addition of H2/CO under different volume ratios and amount. Secondly, revealing the explosion propagation characteristics of CH4-Air with H2/CO addition, such as the evolution of explosion flame front and the coupling mechanism of shock wave and flame front, etc. Thirdly, establishing the intrinsic correlation of macro-to-micro characteristics by relating the elementary reaction kinetics processes and the explosion characteristics. In the experiments, the synchronized pressure/high speed photography test technology was used to obtain the pressure and flame characteristics in the 20L spherical vessel and explosion propagation tube. An image edge processing method based on the ‘improved-Canny’ model was employed to identify and to extract the flame characteristic parameters. The initial linear flame speed was defined. The parameters of gas explosion index, laminar burning velocity and heat loss under various working conditions were obtained by theoretical model on basis of the thermal-dynamic model. In aspect of numerical simulation, the CFD code of CHEMKIN Pro was used to analyze the kinetics process in a zero-dimensional homogenization reactor, basing on the scheme of GRI-Mech 3.0. The contents, production rates and sensitive coefficients of the main components and key intermediates in the reaction of the system were obtained. Within the 60% addition of H2/CO mixtures，the laminar burning velocity of 7% methane was increased, so was the fuel-air ratio of the system, rising the explosion pressure parameters to the maximum value. The explosion time parameters were gradually shortened to the minimum, and the deflagration index was greatly increased. The increment amount increased the system's oxygen-lean level, reduced the laminar burning velocity, and the corresponding characteristic parameters were simultaneously weakened. The effects of H2/CO on the explosion characteristic parameters of 9.5% and 12% methane were similar. The addition of H2/CO mixtures changes the physicochemical characteristics of the mixed system and the laminar burning velocities, which in turn causes the change of macroscopic explosion characteristics. For the same amount of H2/CO mixtures, the higher hydrogen component contributes more to the methane explosion promotion effect. The increasing amount of carbon monoxide exhibits a dual effect on the methane explosion. There is an application limitation for the laminar flame velocity model based on the ideal spherical flame propagation theory. The flame propagation process changes due to the buoyancy effect when the hybrid system approaches the upper flammable limit. At this condition, the calculated result would have a large error. The dimensionless factor Richardson number and the Damköhler number can be used to quantify the behavior of the floating flame during the explosion. When the Richardson number is greater than the critical value of 0.1, the development of the explosion flame is mainly affected by the buoyancy caused by the density difference between the burned zone and the unburned zone. At this time, the Damköhler number of the mixed system is greater than 1, and the laminar burning velocity is bigger than flame rising speed. Moreover, there is a close relationship between the ratio of these two parameters and the rising flame morphology characteristics. The experimental study on the characteristics of explosion propagation was conducted, and the influences of H2/CO mixtures on the explosion propagation characteristics of methane were obtained. The H2/CO mixtures promoted the 7% methane explosion flame propagation in the range of 0 to 60% of the addition amount, and the flame front velocity was gradually increased to the peak value. Under the same addition amount, the higher the H2 ratio in the H2/CO mixtures, the higher the flame front velocity of the mixed system. Due to the change of heat loss during the explosion propagation in the experimental pipeline, the CO did not exhibit the dual effects of damping/promoting. Within 40% of the addition, the H2/CO mixtures with H2 ratio greater than 50% increased the flame front velocity of 9.5% methane. For that of the H2 ratio less than 50%, the flame front velocity in the second window was slightly increased, while that in the third window was slowed down. The H2/CO mixtures exacerbated the oxygen depletion of 12% methane, resulting in a greatly reducing rate of flame propagation. The detailed kinetic simulation results show that the explosion promoting effects of H2/CO mixtures on methane explosion were derived from the increasing production rates on key free radicals of O, H and OH. Thus, the dehydrogenation reaction of methane occurs through steps of OH + CH4 ⇌ CH3 + H2O, H + CH4 ⇌ CH3 + H2 and O + CH4 ⇌ OH + CH3. These reactions exacerbate the chain-branching processes. Overall, the effects of H2/CO mixtures on methane explosion were mainly through the steps of O + H2 ⇌ H + OH, H + O2 ⇌ O +OH, OH+ H2 ⇌ H + H2O and OH + CO ⇌ H + CO2. The H2/CO mixture with a higher H2 ratio has a more significant effect on the content of three key free radicals.