论文部分内容阅读
为了给减弱公路隧道洞口废气窜流提供洞口土建结构设计方案,对洞口废气窜流影响的显著性因素进行了探讨,从洞口纵向错开不同距离、洞外设置不同位置及高度的挡壁等结构因素出发,借助计算流体动力学技术,进行了多因素异水平混合型数值模拟正交试验,探讨了不利自然风条件下洞外不同组合结构因素对洞口废气窜流的影响规律。结果表明:不同结构因素组合对废气窜流改善效果明显不同,洞口纵向错开改善窜流效果最为明显;在隧道出口侧设置有挡壁的所有组合结构均能较好地改善出口废气窜流,其中最有效的是同时在出口侧、中侧、入口侧设置与洞口等高的挡壁;仅在洞外中侧设置中间挡壁,其高度约为洞口高度的2倍时,可以有效改善废气窜流,其他情况下采用高挡壁结构的改善效果不佳;若同时在两隧道中侧与入口隧道侧设置挡壁则废气窜流改善效果差;若仅在入口隧道侧设置长挡壁,则加剧废气窜流。
In order to provide the tunnel civil engineering structure design scheme to reduce the channeling of exhaust gas in the tunnel entrance of tunnel, the significant factors that affect the channeling effect of exhaust gas in the tunnel are discussed. The structural factors such as the wall with different positions and heights Based on computational fluid dynamics (CFD), a multi-factor and hetero-level hybrid numerical simulation orthogonal experiment was carried out to study the influence of different combinations of structural factors on the cross-flow of the tunnel inlet under adverse natural wind conditions. The results show that the combination of different structural factors has significantly different effects on the improvement of the flue gas crossover, and the effect of channeling is most obvious when the openings are staggered longitudinally. All the composite structures with the baffles provided on the exit side of the tunnel can better improve the outlet gas cross-flow, The most effective way is to set the wall with the same height as the hole at the exit side, middle side and entrance side. Only when the middle wall is provided at the middle of the hole, the height is about twice of the height of the hole, Flow, other cases, the use of high retaining wall structure to improve the effect of poor; if at the same time in both sides of the tunnel and the entrance side of the tunnel to set the wall to improve the effect of poor gas channeling; if only the entrance side of the tunnel set long wall, Exacerbating the gas channeling.