underground railway train

基本解释

The train went through an underground railway.
火车穿过一段地下铁道。
Establishing a CFD physical model based on the mathematical model of developing process of fire and smoke in underground railway, numerically simulates the train fire in island station without shield.
以地铁火灾与烟气发展过程的数学模型为基础，建立CFD模拟的物理模型，对岛式无屏蔽门的地铁车站列车火灾进行了数值模拟。

At any rate, the sheikh can console himself with the knowledge that the metro will be the world's biggest computer-operated train system, and its Union Station will have the world's biggest underground railway concourse.
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Yet it is just the highest profile in a string of big-ticket projects — including a concert hall in Hamburg, railway tunnels in Munich and Leipzig, a subway line in Cologne and a Stuttgart underground train station — that have been plagued by huge cost overruns and delays.
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