The effects of a stabilizer and the annular co-flow air speed on turbulent nonpremixed methane flames stabilized downstream of a conical bluff body were investigated. Four bluff body variants were designed by changing the outer diameter of a conically shaped object. The co-flow velocity was varied from zero to 7.4 m/s, while the fuel velocity was kept constant at 15 m/s. Radial distributions of temperature and velocity were measured in detail in the recirculation zone at vertical locations of 0.5D, 1D and 1.5D. Measurements also included the CO₂, CO, NO_x and O₂ emissions at points downstream of the recirculation region. Flames were visualized under 20 different conditions, revealing various modes of combustion. The results evidenced that not only the co-flow velocity but also the bluff body diameter play important roles in the structure of the recirculation zone and, hence, the flame behavior.

研究了稳定器和环形同向气流速度对锥形钝体下游稳定的湍流非预混甲烷火焰的影响。通过改变圆锥形物体的外径，设计了四个钝体变形。并流速度从零变化到7.4 m / s，而燃料速度保持恒定在15 m / s。在0.5的垂直位置进行了详细的测定在回流区的温度和速度的径向分布d，1 d和1.5 d。测量还包括CO ₂，CO，NO _x和O ₂再循环区域下游点的排放。火焰在20种不同条件下可视化，揭示了各种燃烧模式。结果表明，不仅同流速度而且钝体直径在再循环区的结构中以及因此在火焰行为中都起着重要的作用。