LI Tian, DAI Zhi-yuan, ZHANG Ji-ye, ZHANG Wei-hua. Theoretical model and calculation of static leakage for train air tightness[J]. Journal of Traffic and Transportation Engineering, 2020, 20(1): 150-158. doi: 10.19818/j.cnki.1671-1637.2020.01.012
Citation: LI Tian, DAI Zhi-yuan, ZHANG Ji-ye, ZHANG Wei-hua. Theoretical model and calculation of static leakage for train air tightness[J]. Journal of Traffic and Transportation Engineering, 2020, 20(1): 150-158. doi: 10.19818/j.cnki.1671-1637.2020.01.012

Theoretical model and calculation of static leakage for train air tightness

doi: 10.19818/j.cnki.1671-1637.2020.01.012
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  • Author Bio:

    LI Tian(1984-), male, associate professor, PhD, litian2008@home.swjtu.edu.cn

  • Received Date: 2019-08-01
  • Publish Date: 2020-02-25
  • Based on the one-dimensional isentropic flow theory, the state equations of static leakage for the train air tightness were derived. The calculation formulas for the leakage time of pressure drop and the total leakage time were obtained considering the flow coefficient of leakage hole. The dynamic process of static leakage for the train air tightness was numerically simulated. The effects of slenderness ratio of leakage hole and the initial air pressure inside the car body on the train air tightness were studied when the slenderness ratios are 1∶1, 1∶4, 1∶8, and 1∶16, and the initial air pressures inside the car body are 6, 5, 4, and 3 kPa, respectively. Analysis result shows that the pressure drop times calculated by the numerical simulation and the theoretical formula are 20.25, 20.23 s, respectively, when the air pressure inside the car body drops from 3.0 kPa to 0.8 kPa, and the relative errors between them and the experimental results are 1.41% and 1.51%, respectively. When the slenderness ratios of leakage hole are 1∶8 and 1∶16, the time history curves of air pressure drop inside the car body are basically the same, and the air flow rate of leakage hole remains unchanged. During the leakage process, the air flow velocity of leakage hole shows the distribution characteristics of large in the middle and small around. This is caused by the viscous effect of leakage hole wall surface. According to the central velocity and mass flow rate at the outlet section, the flow coefficient of leakage hole is 0.71. The effect of initial air pressure inside the car body on the same specified pressure drop time is less than 1%. If the pressure drop range is the same, the pressure drop time decreases with the increase of initial air pressure, the time for the pressure to drop from 4 kPa to 1 kPa is 24.18 s, and the time for the pressure to drop from 5 kPa to 2 kPa is 19.80 s. The maximum relative error between the results of numerical simulation and the theoretical calculation is 1.22%, indicating that the theoretical model and numerical simulation calculation method can be applied to calculate the leakage area or the air tightness of train.

     

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  • [1]
    WANG Qian-xuan, HU Zhe-long, LIANG Xi-feng, et al. Relationship among internal pressure, body air tightness and external pressure of rail vehicle[J]. Journal of Traffic and Transportation Engineering, 2018, 18(4): 103-111. (in Chinese). doi: 10.3969/j.issn.1671-1637.2018.04.011
    [2]
    XU Wei. Study on air tightness and human safety standards of high-speed trains[J]. Rolling Stock, 1995, 33(10): 32-34. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-TDCL510.008.htm
    [3]
    ZHANG Guang-peng, LEI Bo, LI Qiong. Influence of maglev train sealing characters on the tunnel cross-section area[J]. Journal of the China Railway Society, 2005, 27(2): 126-129. (in Chinese). doi: 10.3321/j.issn:1001-8360.2005.02.023
    [4]
    QIAN Li-xin. Summary of the technical development of high-speed train with the speed of 350 km·h-1 in the world[J]. China Railway Science, 2007, 28(4): 66-72. (in Chinese). doi: 10.3321/j.issn:1001-4632.2007.04.013
    [5]
    WANG Qian-xuan, LIANG Xi-feng, REN Xin. Experimental research on simulation of interior pressure of train passing through tunnel at high speed[J]. Journal of Central South University (Science and Technology), 2014, 45(5): 1699-1704. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-ZNGD201405044.htm
    [6]
    WANG Yue-xin, ZHANG She, ZHONG Shi-hang. Transient pressure field and comfort standards for high-speed trains passing through tunnels[J]. Railway Engineering, 1994(1): 10-12. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-TDJZ401.004.htm
    [7]
    SU Xiao-feng, CHENG Jian-feng, HAN Zeng-sheng. Survey on research of air tightness of high-speed trains[J]. Rolling Stock, 2004, 42(5): 16-19. (in Chinese). doi: 10.3969/j.issn.1002-7602.2004.05.005
    [8]
    JO Y D, AHN B J. Analysis of hazard areas associated with high-pressure natural-gas pipelines[J]. Journal of Loss Prevention in the Process Industries, 2002, 15(3): 179-188. doi: 10.1016/S0950-4230(02)00007-4
    [9]
    OKE A, MAHGEREFTEH H, ECONOMOU I, et al. A transient outflow model for pipeline puncture[J]. Chemical Engineering Science, 2003, 58(20): 4591-4604. doi: 10.1016/S0009-2509(03)00338-5
    [10]
    YAN Bing, DONG Da-wei, HUA Chun-rong, et al. A new diagnosis method of individual cylinder gas leakage by phase analysis of crankshaft torsional vibration[J]. Journal of the China Railway Society, 2003, 25(5): 19-23. (in Chinese). doi: 10.3321/j.issn:1001-8360.2003.05.004
    [11]
    ZHANG Jin-jin, MA Chao-yong, BAI Guo, et al. Differential pressure method applying on air tightness for brake master cylinder of automobile[J]. Machinery Design and Manufacture, 2007(5): 116-118. (in Chinese). doi: 10.3969/j.issn.1001-3997.2007.05.049
    [12]
    LI Yu-jie, MEI Yuan-gui. Primary discussion about pressure tightness of electric multiple units[J]. Railway Locomotive and Car, 2009, 29(2): 31-35. (in Chinese). doi: 10.3969/j.issn.1008-7842.2009.02.008
    [13]
    LI Guo-qing, LI Ming, GUO Wei, et al. Leading car air tightness assessment of high-speed inspection train[J]. Electric Drive for Locomotives, 2012(3): 45-48. (in Chinese). doi: 10.3969/j.issn.1000-128X.2012.03.013
    [14]
    KWON H B, YUN S H, NAM S W. Numerical simulation of pressure change inside cabin of a train passing through a tunnel[J]. Journal of Computational Fluids Engineering, 2012, 17(1): 23-28. doi: 10.6112/kscfe.2012.17.1.023
    [15]
    KWON H B. A study on the minimum cross-sectional area of high-speed railway tunnel satisfying passenger ear discomfort criteria[J]. Journal of Computational Fluids Engineering, 2015, 20(3): 62-69. doi: 10.6112/kscfe.2015.20.3.62
    [16]
    LIU Dong-xue, JIANG Ya-nan, YANG Ming-zhi. Study on tunnel aerodynamic of subway train during acceleration[J]. Journal of Railway Science and Engineering, 2018, 15(1): 178-187. (in Chinese). doi: 10.3969/j.issn.1672-7029.2018.01.025
    [17]
    SHAO Huan-xia, MEI Yuan-gui, ZHOU Chao-hui. Study on numerical simulation of pressure changes inside high-speed air-conditioned train passing through tunnels[J]. Railway Locomotive and Car, 2006, 26(1): 31-33. (in Chinese). doi: 10.3969/j.issn.1008-7842.2006.01.009
    [18]
    MEI Yuan-gui, SUN Jian-cheng, XU Jian-lin, et al. Crossing pressure wave characteristics of high-speed trains in tunne[J]. Journal of Traffic and Transportation Engineering, 2015, 15(5): 34-43. (in Chinese). doi: 10.3969/j.issn.1671-1637.2015.05.005
    [19]
    ZHANG Guang-peng, LEI Bo. The thermal dynamics model for calculating the interior pressure of high-speed trains[J]. Journal of the China Railway Society, 2006, 28(1): 35-38. (in Chinese). doi: 10.3321/j.issn:1001-8360.2006.01.008
    [20]
    XU Liang-zhong, LIANG Xi-feng, LIU Tang-hong, et al. Pressure variation test inside full-scale high-speed train running in open area[J]. Journal of Central South University (Science and Technology), 2014, 45(8): 2878-2884. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-ZNGD201408047.htm
    [21]
    SUN Zhen-xu, YANG Guo-wei, ZHU Lan. Study on the critical diameter of the subway tunnel based on the pressure variation[J]. Science China Technological Sciences, 2014, 57(10): 2037-2043. doi: 10.1007/s11431-014-5664-4
    [22]
    CHEN Chun-jun, NIE Xi-cheng, TANG Meng. Transfer function model of the air pressure inside CRH2 EMU under outside air pressure[J]. China Railway Science, 2013, 34(4): 84-88. (in Chinese). doi: 10.3969/j.issn.1001-4632.2013.04.14
    [23]
    ZHANG Fang-tao, LI Wen-biao, LI Bing. Technical discussion of the EMU air tightness[J]. Railway Locomotive and Car, 2015, 35(6): 44-46. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-TDJC201506013.htm
    [24]
    PENG Guang-zheng, JI Chun-hua, GE Nan. Current status and future development of air tightness detection technique[J]. Machine Tool and Hydraulics, 2008, 36(11): 172-174. (in Chinese). doi: 10.3969/j.issn.1001-3881.2008.11.059
    [25]
    LI Wen-xia, XU Shi-dong. Air tightness technology and standard of high-speed multiple unit and passenger car[J]. Railway Quality Control, 2013, 41(5): 10-12. (in Chinese). doi: 10.3969/j.issn.1006-9178.2013.05.004
    [26]
    WANG Yue-ming. Problem about the railway coach airproof[J]. Railway Locomotive and Car, 2000, 20(4): 4-7. (in Chinese). doi: 10.3969/j.issn.1008-7842.2000.04.002
    [27]
    LIU He-ping, LIU Ran, LIU Dian-hai, et al. Application of ultrasonic leak detection on the air tightness testing of high speed EMU[J]. Machinery Design and Manufacture, 2016(11): 59-62. (in Chinese). doi: 10.3969/j.issn.1001-3997.2016.11.015
    [28]
    ZHOU Jun-chao, HE Zhu-lin, HAN Long. Research and implementation on the control system for high-speed train air tightness[J]. Techniques of Automation and Applications, 2015, 34(6): 64-66. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-ZDHJ201506015.htm
    [29]
    YIN Fa-wei, CHEN Xing-gang, GAO Xing-hua. Research of EMU tightness test device[J]. Rolling Stock, 2014, 52(7): 35-36. (in Chinese). doi: 10.3969/j.issn.1002-7602.2014.07.015
    [30]
    LI Tian, HEMIDA H, ZHANG Ji-ye, et al. Comparisons of shear stress transport and detached eddy simulations of the flow around trains[J]. Journal of Fluids Engineering, 2018, 140(11): 111108-1-12. doi: 10.1115/1.4040672
    [31]
    LI Tian, QIN Deng, ZHANG Ji-ye. Effect of RANS turbulence model on aerodynamic behavior of trains in crosswind[J]. Chinese Journal of Mechanical Engineering, 2019, 32: 85. doi: 10.1186/s10033-019-0402-2
    [32]
    LI Tian, ZHANG Ji-ye, MOHAMMAD R, et al. On the Reynolds-averaged Navier-Stokes modelling of the flow around a simplified train in crosswinds[J]. Journal of Applied Fluid Mechanics, 2019, 12(2): 551-563.

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