香港某高架车站室内热环境的CFD研究

Thermal Comfort Improvement Study for an Elevated Station in Hong Kong

为减少对周围环境的干扰，香港某高架车站使用隔音屏障完全封闭月台与轨道，使得该车站成为隧道形构造。尽管车站的月台以及连接月台的行人天桥都安装了机械通风及空调系统，但由于该车站的特殊构造，月台以及行人天桥的环境温度较一般情况为高，特别是在夏季。通过实地考察发现，造成高温的原因是列车运行引起的活塞效应以及列车的冷凝装置排出的高温废气。行人天桥内透过玻璃幕墙的太阳辐射、空调系统的老化以及布置方式也是造成温度较高的原因。针对上述问题，结合车站的实际情况，本文提出了一系列的改进措施，并使用计算流体力学（CFD）进行计算模拟，以评估改进措施的效果。

To mitigate noise pollution from railway, an elevated station in Hong Kong were totally enclosed by the noise barrier such that the station is tunnel-shaped. Although mechanical ventilation system is provided for the platform level and the footbridge linking platforms, higher temperature is recorded, especially in summer. Through site inspection, it was found that the main reason is the piston effect of train movement. Besides, the exhausted air from condensing units of trains was found to be another heat source of platform level. For the footbridge, high intensity of solar radiation penetrated the glazing cause the rise of temperature. The deterioration of the MVAC system and direction of the air diffusers also contribute to the temperature rise. In respect to the findings, improvement measures were proposed in this paper. Computational Fluid Dynamics （CFD） simulations were conducted to access the performance of proposed measures.