Study on the Temperature Prediction Formula and Application in Urban Utility Tunnels
(1. School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031; 2. Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, Southwest Jiaotong University, Chengdu 610031; 3. Nagqu Shuanggao Green Building Research Co., Ltd., Nagqu 854000; 4. Central Southern China Electric Power Design Institute Co., Ltd., China Power Engineering Consulting Group, Wuhan 430061; 5. Tibet Jinchen Engineering Project Management Consulting Co., Ltd., Lhasa 850030)
Abstract：
The temperature inside urban utility tunnels is a critical factor affecting their safe operation. To address the challenges of predicting tunnel interior temperature, a temperature prediction formula for utility tunnels is developed based on heat transfer theory. Firstly, the thermal equilibrium equation of the tunnel interior is derived by analyzing the heat transfer process between the tunnel and the surrounding soil. Secondly, a parameterized prediction formula for tunnel interior temperature is established by introducing a fitting formula for the temperature difference between the tunnel air and wall surfaces. Finally, the results of the prediction formula are compared with measured data and numerical simulation results.The study results demonstrate that the proposed temperature prediction formula has reasonable accuracy. Compared to measured data, the average error for air temperature is 1.57%, and for wall surface temperature, it is 12.14%. When compared with numerical simulation results, the temperature difference remains within 1.8°C.The formula is applied to analyze the temperature of a utility tunnel in Chengdu. Results indicate no risk of condensation from August to November, as the atmospheric temperature is lower than the wall surface temperature, requiring only basic ventilation. However, during February to May, condensation risk is high due to atmospheric temperatures exceeding wall surface temperatures. In this period, in addition to basic ventilation, an increased airflow rate is necessary to mitigate condensation.
PENG Zi1,
2 WEN Meng3 CHEN Yuan4 DENG Yu5 GUO Chun1,
2
.Study on the Temperature Prediction Formula and Application in Urban Utility Tunnels[J] MODERN TUNNELLING TECHNOLOGY, 2024,V61(6): 74-81
2024, Vol. 61 