Several typical turbulent methane-air jet flames used in the research of turbulent combustion are simulated by the PaSR model with a reduced detailed chemical kinetics. Modeled results are validated by a group of corresponding authoritative experimental data. The mean distributions of the temperature, velocity and species concentration are compared. Different time scales of flow and combustion in these reacting systems, as well as the relation between mixing and combustion process are also investigated. The computational results indicate that the PaSR model can satisfactorily predict the changes in flow field and species concentrations during the course of a reaction. It is found that the local mixing progress play a dominant role on combustion process and flame structure near the flame surface, where the time scale of flow is comparable to it of combustion. The analysis based on PaSR model is consistent well with the flame/vortex interaction spectral diagram in the turbulent flame theory.%采用PaSR湍流燃烧模型对湍流燃烧研究中典型的甲烷湍流射流火焰进行了数值模拟.计算采用简化的化学反应机理,并将计算得到的平均温度场、速度场和各组分的分布与相应的权威实验数据进行了对比.对反应系统中流动和燃烧的不同时间尺度以及二者之间的关系作了探讨.计算结果表明,PaSR模型能够很好地模拟燃烧过程中流场和组分的变化.在火焰面附近,由于流动时间尺度与燃烧的时间尺度量级相当,局部混合作用在决定燃烧过程和火焰结构中发挥重要作用.基于PaSR模型的时间尺度分析与湍流火焰理论中火焰/涡旋相互作用的图谱是一致的.
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