旋流非预混燃烧火焰流动特性的实验研究

利用粒子图像速度场测量技术(PIV)对不同工况下的旋流非预混燃烧流场进行了测量,考察不同燃空速度比下旋流火焰的流动特性.结果表明,轴向截面上径向平均速度流场以燃烧器轴线呈中心对称,轴向平均速度、轴向脉动速度和径向脉动速度沿燃烧器轴线成对称分布,且轴向平均速度和轴向脉动速度的最大值出现在轴线处.随燃空速度比的增大,轴向平均速度和脉动速度增大,随着与燃烧器表面的距离增加,流场截面上轴向平均速度和脉动速度差异不断减小.

EXPERIMENTAL STUDY ON FLOW STRUCTURES OF NON-PREMIXED SWIRLING FLAMES

Experiments are performed to investigate the characteristic modes and structures of nonpremixed swirling flames.With PIV technique,the velocity distributions of the non-premixed swirling flames with difierent fuel jet to annular air flow velocity ratios are observed.The results show that the radial profiles of mean radial velocity are centro-symmetric along the axis of burner.The distributions of axial mean velocity,axial root-mean-squared fluctuating velocity(rms)and radial root-mean-squared fluctuating velocity are symmetrical along the axis of burner,and the maximums of axial mean and rms velocity are at the center of axial sections.With an increase of the fuel to air velocity ratio.axial mean and tins velocity add.By adding the distance between axial section and the surface of burner,the ditierences of the radial profiles of axial mean and rms velocity reduces continuously.