隧道运营期内部空气温度的预测分析

运营隧道内空气温度的合理预测有助于改善隧道内部环境。为了准确预测分析运营隧道内气温，引入传热第三类边界条件，耦合隧道径向及轴向二维轴对称的围岩温度导热方程与洞内气流温度方程，推导出隧道空气温度和内壁面温度的分析解，该分析解法与文献报道数值解法计算得到的巷道内气温差值在０．５℃以内。以武汉长江隧道为例，对运营隧道内的空气温度进行计算分析。结果表明：洞内气温的计算结果与实测数据的差值大多在１℃以内，且温度变化趋势一致，进一步验证了本文分析解的正确性；随着风速的增加，出口气温不断降低且降幅逐渐减小，即降温效果已逐渐不明显，表明运营隧道内的风速控制需综合考虑降温效果和动力消耗。

Prediction and Analysis of Internal Air Temperature during Operation Period of Tunnel

The rational prediction of the air temperature in a running tunnel can help improving the tunnel environment. An axisymmetric two dimensional heat conduction model of the surrounding rock combining radial and axial heat flow is derived and an air/surrounding rock heat exchange model is given. And then the two models are coupled by introducing the third type boundary conditions. The analytical solutions of the surrounding rock temperature and air temperature in tunnels are further deduced. The temperature difference in the roadway calculated by the analytical solution and the numerical solution reported in the literature is within 0.5 ℃. The Wuhan Yangtze River Tunnel is taken as an example to calculate and analyze the air temperature in the tunnel. The results show that: (1) The difference between the calculation results of the temperature in the tunnel and the measured data is mostly within 1 ℃, and the temperature variation trend is consistent, which verifies the correctness of the analytical solution recommended. (2) With the increase of the wind speed, the outlet temperature keeps decreasing and the decrease gradually decreases, i.e. the cooling effect has gradually become insignificant, which indicates that the wind speed control in the running tunnel needs to consider both the cooling effect and power consumption.