The influence of cross flow combined with leeward obstacle on flame length and thermal radiation of buoyant flame: An experimental study
摘要
When a fire breaks out, the flame will release a lot of heat and harm people and property. Generally, the surrounding area is not empty, and the flame combustion is often affected by terrain or other obstacles which will affects the morphology and thermal transfer of the flame. This work investigates the influence of the leeward obstacle on flame length and thermal radiation of buoyant flame under cross flow. The distance between the obstacle and the burner center ranges from 0.15 to 0.45 m and the cross flow velocity ranges from 0 to 1.56 m s−1. Experimental results show that the flame length decreases as the obstacle approaches the burner which are contributed to the vortexes according to the results of Fire Dynamics Simulator. The obstacle has a shielding effect on the flame radiation behind the obstacle, and the shielding effect decreases with the increase of the downstream distance. At the same downstream position, the shielding effect is weakened as the obstacle approaches the burner. Scaling analysis and general models of flame length and dimensionless flame radiant heat flux are proposed respectively.