To analyze the influence of a curved ceiling and fire location on the combustion characteristics in a utility tunnel, the burning rate and temperature profile produced by a pool fire beneath a curved ceiling were investigated experimentally and theoretically. The results showed that oxygen supply and heat feedback from the surrounding form a competitive mechanism, determining the evolution of the burning rate. A qualitative analysis was performed to elucidate this competitive mechanism. With the fire source moving close to the sidewall, the positive influence from the heat feedback is is gradually compensated for by the negative influence from oxygen supply limitation. Moreover, it was inferred that the magnitude of decline of the burning rate near the wall has a positive correlation with heat release rate of the fire source. A characteristic inclined angle was defined to replace the changing angle of the curved ceiling along the ceiling jet path. Based on the definition of the characteristic ‘inclined angle’ concept, the relationship between the temperature profile beneath the curved ceiling centerline, tunnel height and horizontal position from fire source was unified by an empirical model. The maximum temperature delay beneath the curved ceiling centerline produced by the pool fire was analyzed by radial flow and one-dimensional flow. The proposed models for radial flow and one-dimensional flow were validated and could effectively predict the maximum temperature delay, which can be applied in utility tunnel’s fire protection engineering.

为了分析弧形天花板和火源位置对综合管廊燃烧特性的影响，从实验和理论上研究了弧形天花板下池火产生的燃烧速率和温度分布。结果表明，供氧和来自周围的热反馈形成竞争机制，决定了燃烧速率的演变。进行定性分析以阐明这种竞争机制。随着火源靠近侧壁，热反馈的积极影响逐渐被供氧限制的消极影响所抵消。此外，推断近壁燃烧速率的下降幅度与火源的热释放速率呈正相关。定义了一个特征倾斜角来代替弯曲天花板沿天花板喷射路径的变化角度。基于特征“倾斜角”概念的定义，通过经验模型统一了弯曲天花板中心线下方的温度剖面、隧道高度和火源水平位置之间的关系。通过径向流和一维流分析了池火产生的弯曲天花板中心线下方的最大温度延迟。所提出的径向流和一维流模型经过验证，可以有效预测最大温度延迟，可应用于综合管廊消防工程。基于特征“倾斜角”概念的定义，通过经验模型统一了弯曲天花板中心线下方的温度剖面、隧道高度和火源水平位置之间的关系。通过径向流和一维流分析了池火产生的弯曲天花板中心线下方的最大温度延迟。所提出的径向流和一维流模型经过验证，可以有效预测最大温度延迟，可应用于综合管廊消防工程。基于特征“倾斜角”概念的定义，通过经验模型统一了弯曲天花板中心线下方的温度剖面、隧道高度和火源水平位置之间的关系。通过径向流和一维流分析了池火产生的弯曲天花板中心线下方的最大温度延迟。所提出的径向流和一维流模型经过验证，可以有效预测最大温度延迟，可应用于综合管廊消防工程。通过径向流和一维流分析了池火产生的弯曲天花板中心线下方的最大温度延迟。所提出的径向流和一维流模型经过验证，可以有效预测最大温度延迟，可应用于综合管廊消防工程。通过径向流和一维流分析了池火产生的弯曲天花板中心线下方的最大温度延迟。所提出的径向流和一维流模型经过验证，可以有效预测最大温度延迟，可应用于综合管廊消防工程。