Reverse-flow combustor is widely used for small engines to overcome high speed shaft whirling problem and to provide a low frontal area. An experimental investigation was carried out to research the flow field characteristics of a reverse-flow combustor in this paper. Different aerodynamic conditions were studied using PIV to reveal the characteristics of both the nonreacting and reacting flow fields. The structure of the nonreacting flow field in the central section shows similarity as the total pressure loss coefficient increases. The penetrating depth, jet angle, recirculation zone position, and the flow streamlines are similar, while the velocity value of the flow field increases. The structure of the reacting flow field on the central section is different from that of nonreacting flow field, but the variation trend of the reacting flow field under different pressure loss coefficient is similar to that of the nonreacting flow field. By examining the nonreacting and reacting flow fields under the same total pressure loss conditions, marked differences were observed in the primary zone close to the swirler outlet. The relative motion between fuel injection, airflow, and combustion affects the flow field in this zone. The velocity with combustion is faster than that of the nonreacting flow because of the increased temperature and heat release.

中文翻译：

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逆流燃烧器流动特性的实验研究

逆流燃烧器广泛用于小型发动机，以克服高速轴涡动问题并提供低正面面积。本文对逆流燃烧器的流场特性进行了实验研究。使用 PIV 研究了不同的空气动力学条件，以揭示非反应流场和反应流场的特征。随着总压损系数的增加，中段非反应流场的结构呈现出相似性。穿透深度、射流角度、回流区位置、流线相似，流场速度值增大。中段反应流场结构与非反应流场结构不同，但反应流场在不同压力损失系数下的变化趋势与非反应流场的变化趋势相似。通过检查相同总压力损失条件下的非反应流场和反应流场，在靠近旋流器出口的主要区域观察到显着差异。燃油喷射、气流和燃烧之间的相对运动影响该区域的流场。由于温度和热量释放的增加，燃烧的速度比非反应流的速度快。燃油喷射、气流和燃烧之间的相对运动影响该区域的流场。由于温度和热量释放的增加，燃烧的速度比非反应流的速度快。燃油喷射、气流和燃烧之间的相对运动影响该区域的流场。由于温度和热量释放的增加，燃烧的速度比非反应流的速度快。