• Title/Summary/Keyword: Micro pressure wave(MPW)

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A study on the characteristics for aerodynamics at high speed in railway tunnels - focused on the micro pressure wave (고속주행시 철도터널내 공기압 특성에 관한 기초연구 - 미기압(MPW)을 중심으로)

  • Kim, Hyo-Gyu;Choi, Pan-Gyu;Yoo, Ji-Oh
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.16 no.2
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    • pp.249-260
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    • 2014
  • When a train enters the tunnel at high speed, the pressure wave occurs. When this pressure wave reaches at the exit of tunnel, some are either emitted to the outside or reflected in tunnel by the form of expansion wave. The wave emitted to the outside forms the impulsive pressure wave. This wave is called 'Micro Pressure Wave'. The micro pressure wave generates noise and vibration around a exit portal of tunnel. When it becomes worse, it causes anxiety for residents and damage to windows. Thus, it requires a counterplan and prediction about the micro pressure wave for high speed railway construction. In this paper, the effects of train head nose and tunnel portal shape were investigated by model test, measurement for the micro pressure wave at the operating tunnel as well as numerical analysis for the gradient of pressure wave in the tunnel. As results, a method for predicting the intensity of the micro pressure wave is suggested and then the intensity of the micro pressure wave is analyzed by the tunnel length and the cross-sectional area.