地下车站排热通风系统困境及其原因探讨
Discussion on predicament and causes of heat rejection and ventilation systems in subway stations
摘要：
对列车空调冷凝器运行热环境的控制能力是衡量地铁车站轨区排热系统性能的重要指标，然而现有排热通风系统客观上存在排热效果不佳、能耗高、风道调试难和施工周期长，以及安全隐患等问题。本文通过对不同车站排热系统的运行状态实测和调研发现，排热系统控温效果不明显、风口风量分布不均，且不同地铁环境中设置排热系统的必要性有差异。进一步对排风口现状典型风量和目标风量下的热环境和排热效率进行了CFD计算和对比分析，结果显示：排热风口风量分布不均是影响排热系统性能的主要原因；当每台冷凝器对应排风量达到2.5 m3/s时，排热效率超过55%、热风比达到16.7 J/m3，系统控制轨区热环境的能力显著提高。
Abstract：
The ability to control the operating thermal environment of the condensers of train air conditioning units is an important indicator to measure the performance of the heat rejection system in the rail area of subway stations, but the existing heat rejection and ventilation system objectively has problems such as poor heat rejection effect, high energy consumption, difficult air duct commissioning, long construction period, and potential safety hazards. Through the actual measurement and investigation of the operating status of the heat rejection system of different stations, it is found that the temperature control effect of the heat rejection system is not obvious, the air volume distribution is uneven, and the necessity of setting up the heat rejection system in different subway environments is different. Furthermore, CFD calculation and comparative analysis of the thermal environment and heat exhaust efficiency under the typical air volume and target air volume of the exhaust air outlets are further carried out, and the results show that the uneven distribution of the air volume of the exhaust air outlets is the main reason affecting the performance of the heat rejection system. When the corresponding exhaust air volume of each condenser reaches 2.5 m3/s, the heat exhaust efficiency exceeds 55% and the heat-air volume ratio reaches 16.7 J/m3, and the systems ability to control the thermal environment of the rail area is significantly improved.
Keywords:subway;heatrejectionsystem;heatexhaustefficiency;heat-airvolumeratio;overtrackexhaustduct;trainairconditioningunit;on-sitemeasurement