极寒地区地下储能库巷道施工通风模拟研究

Study on ventilation simulation of underground energy storage tunnel construction in extreme cold region

摘要

基于某极寒地区大型地下储能洞库工程，对巷道掘进过程的污染物和温度场进行了数值模拟研究。通过对长距离巷道建立了三维数值模型，采用CFD方法对其三维流场及温度场进行了仿真计算，并对数值模拟的合理性进行了验证。据此进一步模拟了不同通风方式下巷道内的风场、CO迁移和分布规律，分析了机械通风对巷道温度场的影响规律，模拟结果表明极寒地区巷道施工通风需综合考虑掌子面附近的污染物场及外界冷空气迁移的影响。压入式通风污染物排出路径较长，污染物浓度达标时间较长，采用排烟窗口排烟污染物达标时间更长，但主巷道内不受洞外冷气的影响，主巷口散烟会在巷道口存在一段稳定的冷热对流交换区。混合式通风污染物可以有效排出，但抽出式风机产生的负压会加速洞外冷空气的灌入，应注意抽送风量的平衡及洞口保温，从而减小冷空气对巷道温度场的影响。

Abstract

Based on a large underground storage tunnel project in a extreme cold area, the numerical simulation of pollutants and temperature field during tunnel excavation is carried out. The three-dimensional numerical model of long tunnel excavated is established, and the three-dimensional flow field and temperature field are simulated by CFD method, and the rationality of the numerical simulation is verified. Accordingly, the wind field and CO migration and distribution rule in the tunnel under different ventilation modes are further simulated, and the influence rule of mechanical ventilation on the temperature field of the tunnel is analyzed. The simulation result show that the pollutant field near the working surface and the influence of external cold air migration should be considered at the same time in tunnel excavation in extreme cold regions. The compressed ventilation has a long discharge path and a longer time for pollutant concentration to reach the standard, and the smoke exhaust window takes a longer time for pollutant concentration to reach the standard. However, the main roadway is not affected by the cold air outside the tunnel, and the loose smoke at the entrance of the main alley will have a stable cooling and heat convection exchange area at the entrance of the roadway.The pollutants can be effectively discharged by using mixed ventilation, however, the negative pressure generated by the extraction fan will accelerate the injection of cold air outside the tunnel. Attention should be paid to the balance of the pumping air volume and the insulation of the entrance, so as to reduce the influence of cold air on the temperature field of the tunnel.

关键词

极寒地区 / 长距离巷道 / CFD模拟 / 压入式通风 / 混合式通风 / CO浓度场 / 温度场

Key words

extreme cold regions / long tunnel excavated / CFD simulation / compressed ventilation / mixed ventilation / CO concentration field / temperature field

Author summay

魏 杰(1992—), 男, 工程师, 硕士, 研究方向为水工水力学及流体力学。E-mail: [e-mail]

基金资助

水能资源利用关键技术湖南省重点实验室开放研究基金项目(PKLHD201804)