Ceiling temperature distribution and decay in tunnel fires: Effect of longitudinal velocity, bifurcated shaft exhaust and fire location
This paper establishes a model tunnel to investigate the impact of longitudinal velocity (u), bifurcated shaft exhaust velocity (BSEV) and fire location on ceiling temperature and decay. The experimental results show that a longitudinal velocity of 0.6 m/s can control the upstream high temperature w...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2023-01-01
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| Series: | Case Studies in Thermal Engineering |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2214157X22008887 |
| _version_ | 1797956210979241984 |
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| author | Liangliang Tao Yanhua Zeng Guichang Yang Dongxu Zhao Jie Li Xiaokang Fu |
| author_facet | Liangliang Tao Yanhua Zeng Guichang Yang Dongxu Zhao Jie Li Xiaokang Fu |
| author_sort | Liangliang Tao |
| collection | DOAJ |
| description | This paper establishes a model tunnel to investigate the impact of longitudinal velocity (u), bifurcated shaft exhaust velocity (BSEV) and fire location on ceiling temperature and decay. The experimental results show that a longitudinal velocity of 0.6 m/s can control the upstream high temperature within 2.5 m when the distance between fire and shaft (D) is 1.0 m, and further increase in longitudinal velocity has little effect on upstream temperature distribution. Downstream temperature profile should be divided into two cases according to the magnitude of longitudinal velocity: the difference between the temperature decay model in low-speed region (u ≤ 0.5 m/s) and that in the high-speed region (u > 0.5 m/s) is particularly obvious with D at 1.0 m, and the downstream temperature decay rate in the low-speed region is the slowest compared to all the working conditions in this paper. For D more than 1.0 m, the range of high temperature distribution increases with D for certain longitudinal velocities (0.6-0.7 m/s); however, at particularly large longitudinal velocity (0.8 m/s), D has almost no effect on the upstream temperature distribution. The effect of longitudinal velocity on upstream temperature is stronger than that of BSEV. The downstream ceiling temperature decay model is little affected by longitudinal velocity and BSEV with D more than 1.0 m. The temperature decay rate first decreases, then increases, and finally decreases again as the D increases. Existing temperature attenuation models cannot predict the temperature profile in longitudinally ventilated tunnels with BSEV, but the temperature decay model considering fire location proposed in this paper can provide a reference value for tunnels with synergistic ventilation of longitudinal ventilation and BSEV. |
| first_indexed | 2024-04-10T23:46:30Z |
| format | Article |
| id | doaj.art-fa006fb6f4a2405793b9a3359c8f529d |
| institution | Directory Open Access Journal |
| issn | 2214-157X |
| language | English |
| last_indexed | 2024-04-10T23:46:30Z |
| publishDate | 2023-01-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Case Studies in Thermal Engineering |
| spelling | doaj.art-fa006fb6f4a2405793b9a3359c8f529d2023-01-11T04:29:19ZengElsevierCase Studies in Thermal Engineering2214-157X2023-01-0141102651Ceiling temperature distribution and decay in tunnel fires: Effect of longitudinal velocity, bifurcated shaft exhaust and fire locationLiangliang Tao0Yanhua Zeng1Guichang Yang2Dongxu Zhao3Jie Li4Xiaokang Fu5School of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 610031, ChinaSchool of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 610031, China; Corresponding author.School of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 610031, ChinaSchool of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 610031, ChinaSchool of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 610031, China; Corresponding author.Shanxi Jingxing Expressway Co., Ltd., Lvliang, Shanxi, 033500, ChinaThis paper establishes a model tunnel to investigate the impact of longitudinal velocity (u), bifurcated shaft exhaust velocity (BSEV) and fire location on ceiling temperature and decay. The experimental results show that a longitudinal velocity of 0.6 m/s can control the upstream high temperature within 2.5 m when the distance between fire and shaft (D) is 1.0 m, and further increase in longitudinal velocity has little effect on upstream temperature distribution. Downstream temperature profile should be divided into two cases according to the magnitude of longitudinal velocity: the difference between the temperature decay model in low-speed region (u ≤ 0.5 m/s) and that in the high-speed region (u > 0.5 m/s) is particularly obvious with D at 1.0 m, and the downstream temperature decay rate in the low-speed region is the slowest compared to all the working conditions in this paper. For D more than 1.0 m, the range of high temperature distribution increases with D for certain longitudinal velocities (0.6-0.7 m/s); however, at particularly large longitudinal velocity (0.8 m/s), D has almost no effect on the upstream temperature distribution. The effect of longitudinal velocity on upstream temperature is stronger than that of BSEV. The downstream ceiling temperature decay model is little affected by longitudinal velocity and BSEV with D more than 1.0 m. The temperature decay rate first decreases, then increases, and finally decreases again as the D increases. Existing temperature attenuation models cannot predict the temperature profile in longitudinally ventilated tunnels with BSEV, but the temperature decay model considering fire location proposed in this paper can provide a reference value for tunnels with synergistic ventilation of longitudinal ventilation and BSEV.http://www.sciencedirect.com/science/article/pii/S2214157X22008887Tunnel fireFire locationBifurcated shaftLongitudinal velocityTemperature distributionTemperature decay |
| spellingShingle | Liangliang Tao Yanhua Zeng Guichang Yang Dongxu Zhao Jie Li Xiaokang Fu Ceiling temperature distribution and decay in tunnel fires: Effect of longitudinal velocity, bifurcated shaft exhaust and fire location Case Studies in Thermal Engineering Tunnel fire Fire location Bifurcated shaft Longitudinal velocity Temperature distribution Temperature decay |
| title | Ceiling temperature distribution and decay in tunnel fires: Effect of longitudinal velocity, bifurcated shaft exhaust and fire location |
| title_full | Ceiling temperature distribution and decay in tunnel fires: Effect of longitudinal velocity, bifurcated shaft exhaust and fire location |
| title_fullStr | Ceiling temperature distribution and decay in tunnel fires: Effect of longitudinal velocity, bifurcated shaft exhaust and fire location |
| title_full_unstemmed | Ceiling temperature distribution and decay in tunnel fires: Effect of longitudinal velocity, bifurcated shaft exhaust and fire location |
| title_short | Ceiling temperature distribution and decay in tunnel fires: Effect of longitudinal velocity, bifurcated shaft exhaust and fire location |
| title_sort | ceiling temperature distribution and decay in tunnel fires effect of longitudinal velocity bifurcated shaft exhaust and fire location |
| topic | Tunnel fire Fire location Bifurcated shaft Longitudinal velocity Temperature distribution Temperature decay |
| url | http://www.sciencedirect.com/science/article/pii/S2214157X22008887 |
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