综合管廊电缆桥架火灾的温度场分布特性研究

针对综合管廊电缆火灾的危害性，建立了截面尺寸为1:1的综合管廊模型，重点研究电缆桥架火灾造成的受限空间温度场分布。结果表明：烟气的沉降作用可将垂直温度场划分为顶棚射流层、中间热烟气过渡层和底部冷空气层；封堵端口会加快顶棚烟气温度的纵向衰减速度，并分别提出了封堵侧和贯通侧的温度衰减预测模型；对于火源功率较小的电缆桥架火灾，火源功率与顶棚最大温升满足线性关系；通过建立顶棚最大温升预测模型，发现实验值与预测值之间的误差大多维持在30%以内，其中最小的预测误差为14.73%，模型的整体预测效果较好。

Study on temperature field distribution of cable tray fire in utility tunnel

Aiming at the harmfulness of cable fire in utility tunnel, a utility tunnel model with a section size of 1:1 was established. The temperature field distribution in confined space caused by cable tray fire was mainly studied. The results show that the vertical temperature field caused by smoke deposition can be divided into three layers, namely the ceiling jet layer, intermediate hot smoke transition layer and the bottom layer of cold air, respectively. Sealing the portal would accelerate the decay rate of ceiling longitudinal smoke temperature, and the temperature attenuation models of sealing side and through side are given. For the cable tray fire with low fire power, the relationship between the power of fire source and the maximum excess ceiling temperature is linear. Through the establishment of the prediction model of the maximum excess ceiling temperature, it was found that the error between the experimental value and the predicted value are mostly within 30 %, and the minimum prediction error is 14.73 %. The overall prediction effect of the model is good.