Development of Time-series Laser Imaging Techniques of Lean Premixed Flame in a Cylindrical Tube with Swirling Flow and Investigation of Flame Propagation Characteristics

在这项研究中，我们开发了同时显示技术的贫油预混火焰和流场在圆柱玻璃的高速PIV测量。为了研究预混器内的非稳态火焰行为，本文研究了旋流预混燃烧器内火焰传播的特性。采用两种不同的混合气体供给方式，研究了火焰传播特性。在带旋流的闭式旋流器预混器中，火焰的尖端被高度拉伸并被熄灭，火焰进一步向上传播被阻止。在中心开式旋流器的预混器中，证实了火焰被旋流器中心孔冲击流产生的轴向高速区压回预混器下游。

In this study, we developed simultaneous visualizing techniques of lean premixed flame and flow fields in a cylinder glass by high-speed PIV measurement. We present characteristics of flame propagation in a premixed burner with swirling flow in order to investigate unsteady flame behavior in the premixer. Two kinds of mixture gas supply techniques were used in order to investigate the characteristics of flame propagation. In the premixer of the closed center swirler with swirling flow, the tip of the flame was highly stretched and received flame extinction and the flame propagation further upward was prevented. In the premixer of the open center swirler, it was confirmed that flame was pressed back to downstream of the premixer by the axial high velocity region generated by impingement flow from center hole of the swirler.