摘要：A series of experiments were carried out in an arched tunnel (50 m long, 2 m wide, 2.3 m high). Under the influence of aspect ratios (1, 2 and 3) of oil pool and pool orientation relative to sidewall, the flame length and temperature distribution under the arched ceiling was studied. Oil pools with 3 aspect ratios were placed in the center as a control group. Results show that the pool orientation relative to sidewall is a decisive factor affecting the fire behavior. The heat release rate decreases with the aspect ratio increases. According to the physical meaning of flame extending along arched ceiling, the heat release rate is modified and prediction formula of transverse flame length under arched ceiling is obtained. The transverse temperature decay rate of different sections is different because of buoyant force. By modifying the transverse travelling distance, the prediction formula of the transverse temperature distribution is obtained, and the prediction error is within ±15%.
