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分别采用粒子速度影像(PIV)技术和数值模拟方法研究低旋流燃烧器出口下游冷态流场,分析旋流器安装角对低旋流流动结构的影响.结果表明:旋流器安装角与流场中产生回流区时的临界旋流数无关,高旋流与低旋流的分界点约为0.47;安装角较大的旋流器下游流场的发散角和低速区较大;随着轴向距离增大,中心轴线上无量纲轴向速度衰减很快,并且两个旋流器的衰减速率基本相当,左右有两个峰值,安装角较大的旋流器两个峰值衰减速率较大并且峰值之间的距离增大幅度较大;径向速度随着中心射流流速的增大而增大,安装角较大旋流器的径向速度较小;旋流器安装角为40°时后方的流场具有较高的湍动能,火焰传播速度更高.
The effects of cyclone installation angle on the structure of low-swirling flow were analyzed by means of particle velocity imaging (PIV) and numerical simulation respectively. The results show that the installation angle of cyclone The critical swirl number in the flow field is independent of the critical swirl number. The demarcation point between the high swirl flow and the low swirl flow is about 0.47. The divergence angle and low velocity zone of the flow field downstream of the swirler with larger installation angle are larger. The axial distance increases, the dimensionless axial velocity decays rapidly on the central axis, and the decay rates of the two cyclones are basically the same with two peaks on the left and right. The two peak decay rates of the cyclone with larger installation angle And the distance between the peaks increases greatly. The radial velocity increases with the increase of the center jet velocity. The larger the installation angle, the smaller the radial velocity of the cyclone. The cyclone mounting angle is 40 ° When the rear flow field has a high turbulent kinetic energy, flame propagation speed higher.