预混湍流3D火焰面密度和燃料消耗率的估计

Experimental Study on Turbulent Premixed Flames of Syngas Oxyfuel Mixtures at High Pressure With OH-PLIF

利用平面激光诱导荧光(OH-PLIF)技术测量了CH_4/air预混湍流火焰前锋面结构,通过图片处理得到了测量平面上的二维火焰面密度。基于不同的假设建立了三种不同模型,利用二维探测得到的火焰面信息来估计三维火焰面密度在测量面上的值,通过积分三维火焰面密度估计值得到燃烧系统的燃料消耗率。结果表明,预混湍流火焰前锋面为凹凸的褶皱结构,平面测量的二维火焰面密度明显低估了真实的火焰面密度,利用模型估计得到的3D火焰面密度对2D值有明显的改善。燃烧系统的燃料消耗率可以用来评估模型的可靠性,结果表明模型的误差都在40%以内。

Turbulent flame front structureof CH4/air flames were detected using OH-PLIF. 2D Flame surface density （FSD） on the measurement plane was obtained by image processing. Three different models were proposed to estimate 3D FSD value on the measurement plane from the characteristics of 2D images with different assumptions. Moreover, the global fuel consumption rate can be obtained by integrating the 3D FSD within the flame domain. Results show that turbulent flame front are the wrinkled front with convex and concave structures. 2D FSD calculated from planar images underestimate the true value while it can be advanced to 3D FSD by the proposed models. Global fuel consumption rate can be used to evaluated the reliability of the models and results show that the error is within 40% for all models.