The aerodynamic shape design of train head should consider all kinds of factors because the relation between reducing aerodynamic drag and air pressure pulse may be conflictive and uniform.

减小列车空气阻力和降低列车交会压力波，既矛盾又统一，列车气动头部外形设计需要综合考虑各种因素。

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The recuperators have high air resistance , low air preheating temperature and high fan pressure head , and fan has much noise to environment and are apt to break down with vibration .

此换热器空气阻力大，空气预热温度不高，风机压头高，环境噪声大，风机振动大、易损坏。

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Inspection air pressure test(with water head) for No1. water ballast tank(No15 block).

No1压载水舱（No.15分段）气压试验（压头试验）检查。

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