Research on the length of the anti-freezing layer of cold-region tunnels under the influence of train-induced wind
Yan Gao, Yunfei Ding, Yan Feng, Jingjing Xia, Xuezhi Tian, Jiying Geng, Ben‐Guo He
Abstract
The difference between the temperature in a high-speed railway tunnel and that outside the tunnel narrows because of the train-induced wind, and the temperature field in the tunnel differs greatly from that in an ordinary tunnel. Negative temperature distribution occurs in the middle section of a tunnel when traffic density is high, which is detrimental to the anti-freezing design of tunnels in cold regions. A heat transfer model under the effect of train-induced wind was constructed to investigate the influences of different train speeds and intervals between trains on the length of the anti-freezing layer. A model test system was constructed to test anti-freezing systems of cold-region tunnels. The results show that train-induced wind greatly affects the length of the anti-freezing layer of cold-regions tunnels. For every 50 km/h increase in train speed, the average length of the anti-freezing layer increases by 90 m. For every 5 min decrease in the interval between two trains, the average length of the anti-freezing layer increases by 78.2 m. Therefore, the influence of the operating conditions of trains should be taken into account in the anti-freezing design for cold-region tunnels. Air curtains blowing out hot air can effectively prevent freeze damage in cold-region tunnels when trains areoperating.