The effect of canyon cross wind yaw angle on airflow and flame characteristics of ethanol pool fires in a tunnel was investigated. The fire source location and canyon cross wind speed were studied as factors. The wind yaw angle was ranged in 45°–135° with an interval of 15°. The results showed that the flow field in the tunnel presented three different conditions with the boundaries of wind yaw angles 60° and 90°. The mass burning rate and flame tilt characteristics were affected by the flow field near the fire source. The mass burning rate decreased with the increasing wind yaw angle when the wind yaw angle was in 45°–90°, but remained steady when the angle was in 90°–135°. Additionally, a normalized mass burning rate model considering normalized distance to the upstream portal and the wind yaw angle was developed. The flame close to the upstream portal wiggled, rotated and oscillated irregularly due to the influence of turbulence induced by the external canyon cross wind. This made mean flame length and flame tilt angle in turbulence zone different from those in other zones. A prediction correlation between the flame tilt angle and the canyon cross wind speed and yaw angle was established.

研究了峡谷横风偏航角对隧道内乙醇池火灾的气流和火焰特性的影响。研究了火源的位置和峡谷的横风速。风偏角范围为45°–135°，间隔为15°。结果表明，隧道内的流场呈现出三种不同的情况，风偏角分别为60°和90°。燃烧速率和火焰倾斜特性受火源附近流场的影响。当风偏角在45°–90°时，质量燃烧率随风偏角的增加而降低，但在90°–135°时，质量燃烧率保持稳定。另外，建立了考虑到上游入口的归一化距离和偏航角的归一化质量燃烧速率模型。由于外部峡谷侧风引起的湍流的影响，靠近上游入口的火焰不规则地摆动，旋转和振荡。这使得湍流区域中的平均火焰长度和火焰倾斜角不同于其他区域。建立了火焰倾斜角与峡谷横风速和偏航角之间的预测相关性。