Study on effects of the train-induced airflow on the temperature field of high-speed railway tunnels in cold regions. (1st June 2023)

• Record Type: Journal Article
• Authors: Wei, Yong; Sun, Keguo; Zhong, Xingyu; Jia, Jinglong; Huang, Qian; Qin, Jinhang; Xiong, Zhi
• Is Part Of: Thermal science and engineering progress. Volume 41(2023)
• Publication Date: 2023-06-01
• Subjects: Cold region tunnels -- High-speed trains -- Train-induced airflow -- Temperature field; Heat engineering -- Periodicals; Heat engineering; Thermodynamics; Periodicals; 621.402
• DOI: 10.1016/j.tsep.2023.101837
• Languages: English
• ISSNs: 2451-9049

Abstract

Highlights: In winter, the temperature distribution of high-speed railway tunnels in cold regions will vary due to the train-induced airflow, whose effects are mostly unfavorable but sometimes favorable. The duration of the effect of the train-induced airflow is about 16 min. The relationship between the impacts of the train-induced airflow and train speed, travel interval time, and ambient temperature is as follows: (1) The effects of the train-induced airflow on the tunnel temperature field are positively correlated with the train speed. (2) The effects of the train-induced airflow are negatively correlated with the time interval of train travel. (3) The effect of airflow becomes more significant when the ambient temperature decreases. Abstract: High-speed railway tunnels in cold regions often suffer severe frost damage in winter. In these tunnels, the train-induced airflow is generally regarded as an important factor exacerbating frost damage. Thus, the CFD methods were used in this paper to investigate the effects of the train-induced airflow on the temperature field of tunnels in cold regions. In this simulation, the behavior of the train passing through the tunnel was simulated using a dynamic mesh technique. The results show that the effects of the train-induced airflow will last for about 16 min when one train passes through the tunnel at 350 km/h. High-speed trains carry large amounts of low-temperature air into the tunnel, resulting in lower tunnel air temperatures and enhancing convective heat transfer between the air and the structure. The effects of the train-induced airflow are proportional to the train's speed. The minimum air temperature of the monitored cross-section at 350 km/h is 12.6% lower than that at 250 km/h. The effects of the train-induced airflow are negatively correlated with the interval between two trains passing through the tunnel. For every 5 min of interval time reduction, the local lowest air temperature drops by 0.55 ℃ and the heat dissipation rate of the structure increases by 12.3%. The lower the ambient temperature, the more significant the temperature drop caused by the train-induced airflow. However, the train-induced airflow can be a beneficial factor during the high temperature hours of the day.