高速公路隧道合流段夹角对通风特性影响的数值模拟研究

Numerical Simulation Study on the Influence of Intersection Angle of Confluence Section on Ventilation Characteristics of Freeway Tunnel

文章采用计算流体力学模拟软件(Fluent)对华坪至丽江高速公路彪水岩地下立交隧道合流部进行模拟,综合考虑在流场、风速、风量、风压等多个因素下不同合流夹角对合流隧道通风特性影响研究。研究表明:随着合流夹角的增加,扩大断面段风速、出口风量减小,而入口静压则增大;压损系数越大,气流越不顺畅。合流部局部流段附近均有“回流”和“涡旋”的现象,应设计相应的机械通风设施予以排除;隧道合流部夹角为10°最合理,与工程实际采用方案相同。研究成果可为其优化通风适用性及舒适性进一步分析提供参考数据。

In this paper,computational fluid dynamics(CFD)simulation software(Fluent)is used to simulate the confluence part of Biaoshuiyan underground interchange tunnel on Huaping-Lijiang expressway.The influence of different confluence angles on the ventilation characteristics of the confluence tunnel is studied comprehensively considering the flow field,wind speed,air volume,wind pressure and other factors.The results show that:with the increase of confluence angle,the wind speed and outlet air volume of enlarged section decrease while the inlet static pressure increases;the greater the pressure loss coefficient,the less smooth the airflow.The phenomenon of“backflow”and“vortex”near the local flow section of the confluence should be eliminated by designing corresponding mechanical ventilation facilities;the angle of 10°in the confluence part of tunnel is the most reasonable,which is the same as that of the actual project scheme.The research results can be used as reference data for further optimization of ventilation applicability and comfort analysis.