文氏管长度对双级涡流器出口流场影响的试验研究

采用粒子图像测速仪（Particle image velocimetry, PIV）测量双级涡流器出口流场，改变文氏管长度，探讨文氏管长度对双级涡流器出口流场的影响，揭示了涡流器下游流场特征，获得了沿轴向不同位置的轴向速度和径向速度分布规律。研究表明：随着文氏管长度的增加，涡心发生径向位移，上下涡心的中心距离从22.2 mm增加到了29.2 mm，中心回流区的面积增加，轴向速度和径向速度分布特征有利于燃烧组织。

Experimental Investigation on Effect of Venturi Length on Outlet Flow Field of Double-Stage Swirler

The outlet flow fields of the double-stage swirler with different Venturi length are measured with particle image velocimetry (PIV) and the effect of Venturi length on outlet flow fields is investigated and discussed. The downstream flow field characteristics of swirler are displayed, and the distributions of axial velocity and radial velocity are gained. The results indicated that the radial movement of Vortex core away from center line results in the increase of radial distance from 22.2 mm, to 29.2 mm, and the area of central circulation zone becomes larger with the increase of Venturi length. The characteristics of axial velocity and radial velocity are in favour of combustion organization.