【摘要】 根据气固两相局部非热平衡假设,建立了混合气在惰性多孔介质中预混合燃烧的一维数学模型,研究了不同情况下甲烷-空气的预混合气在多孔介质中燃烧时的温度分布和燃烧速率,并与自由空间中相应的值进行比较.结果表明,多孔介质的存在可以扩展混合气的燃烧极限,明显改善了燃烧室的换热性能,强化了对新鲜混合气的预热,降低了热量损失;在多孔介质中混合气的燃烧温度和燃烧室的温度明显升高,反应区厚度和燃烧速率显著增大.数值结果与其他研究者的实验结果是一致的.更多还原

【Abstract】 One-dimensional mathematical model for the premixed combustion of the mixed gases in inert porous media has been developed based on the hypothesis of local thermal non-equilibrium between the solid and the gas phases by solving separate energy equations for these two phases. The temperature distributions and the burning speed in the porous media are examined in different cases and compared to those in free flame. The results show that the existence of the porous media intends to expand combustible limit of the premixed gases, obviously improves heat transfer in the chamber, enhances preheating to fresh mixture and reduces heat loss. The combustion temperature and the temperature of the chamber are increased evidently in the porous media and the thickness of combustion zone and the burning speed are also increased. The numerical results agree well with the experimental observation of previous researchers.更多还原