Massey James C, Langella Ivan, Swaminathan Nedunchezhian
Department of Engineering, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ UK.
Flow Turbul Combust. 2018;101(4):973-992. doi: 10.1007/s10494-018-9948-9. Epub 2018 Aug 15.
Large Eddy Simulations of an unconfined turbulent lean premixed flame, which is stabilised behind a bluff body, are conducted using unstrained flamelets as the sub-grid scale combustion closure. The statistics from the simulations are compared with the corresponding data obtained from the experiment and it is demonstrated that the experimental observations are well captured. The relative positioning of the shear layers and the flame brush are analysed to understand the radial variations of the turbulent kinetic energy at various streamwise locations. These results are also compared to confined bluff body stabilised flames, to shed light on the relative role of incoming and shear driven turbulence on the behaviour of the flame brush and the turbulent kinetic energy variation across it.
使用无应变小火焰作为亚网格尺度燃烧封闭模型,对钝体后方稳定的无约束湍流贫预混火焰进行了大涡模拟。将模拟得到的统计数据与实验获得的相应数据进行比较,结果表明实验观测结果得到了很好的捕捉。分析了剪切层和火焰刷的相对位置,以了解不同流向位置处湍动能的径向变化。这些结果还与受限钝体稳定火焰进行了比较,以阐明来流湍流和剪切驱动湍流对火焰刷行为以及火焰刷上湍动能变化的相对作用。