寒区隧道消防管道温度场三维分析

3D analysis of temperature field of tunnel fire pipeline in cold area

为避免寒区隧道的消防系统由于水源与管道内水在低温下冻结而失效,基于有限元分析,对寒区隧道温度在空间与时间上的分布进行预测。采用无线传感器对背景工程隧道洞外、洞口、洞中段、洞尾的温度变化进行实时监测,作为后续模拟的边界条件。对50 m断面处隧道温度场进行了二维模拟,发现消防管道的温度在第1年即稳定。三维分析中考虑1 a的分析期,得出温度分布。根据三维模型的计算,最低温度出现时,隧道深度约700 m位置为正、负温的交界点,深度小于700 m时温度为负温。

In order to avoid the failure of tunnel fire control system in cold area due to freezing of water source and water in pipeline at low temperature,based on the finite element analysis,temperature distribution in space and time in tunnels in cold regions was predicted.Real-time monitoring of temperature changes outside the tunnel,at the entrance of tunnel,in the middle of tunnel and at the end of tunnel in background engineering was carried out by wire less sensor to put boundary conditions for subsequent simulation.The temperature field of tunnel at 50 m section was simulated in two dimensions.It is found that the temperature of fire pipeline is stable in the first year.The temperature distribution was obtained considering one-year analysis period in 3D analysis.Based on the calculation of 3D model,when the temperature reaches the lowest level,depth of the junction point of the positive and negative temperature of the tunnel is about 700 m.The negative temperature appears at the location of the tunnel when the depth is less than 700 m.