双洞毗邻隧道洞口污染物窜流的数值模拟研究

发布时间：2018-03-29 07:03

本文选题：双洞毗邻隧道　切入点：污染物扩散　出处：《西南交通大学》2016年硕士论文

【摘要】：随着高速公路不断向山区发展,隧道及隧道群的建设已经成为需要重点攻关的工程项目。另外,为了更好地利用车辆行驶产生的交通风,双洞的单向隧道已经成为常见的隧道形式,而纵向通风也成为最常采用的隧道通风方式。对于上下游间距较近的双洞毗邻隧道,排风隧道排出的污染物会对洞外环境产生污染,同时也窜流进入进风隧道产生“二次污染”。窜流问题的存在会使得窜流的隧道通风效率降低,通风效果达不到预期效果。论文先就洞口污染物扩散问题,对国内外研究现状作出综述,了解到数值模拟方法在该领域的普遍性,也发现目前大多数研究都是洞口扩散、单洞毗邻隧道窜流以及双洞横向窜流,而在双洞毗邻隧道的窜流问题上缺乏研究。本文从试验数据出发,在对数值模拟方法进行验证后,确定了采用FLUENT软件对问题进行模拟研究的研究方法。针对纵向通风下的双洞毗邻隧道,本文制定了洞口窜流评价方案,并从贴附射流的角度,分析洞口排出的污染物的扩散特征。本文先是在四段隧道通风风速相等的前提下,模拟了通风风速、隧道间距、环境风等主要因素对洞口窜流的影响规律,得出结论,在无环境风影响时,洞口窜流与通风风速大小无关,只与隧道间距有关,而有环境风时,环境风风速和风向都对窜流产生影响。然后模拟了单一排风风速和进风风速对窜流的影响,以及一些特殊工况下的洞口窜流规律。继续探讨了改善洞口窜流的措施,指出目前常见的加筑隔墙和修建明洞两种方案并不适用于双洞毗邻隧道,在此基础上提出在明洞顶设排风天窗这一可行的方案并验证了其可行性。
[Abstract]:With the continuous development of highways into mountainous areas, the construction of tunnels and tunnel groups has become a key project that needs to be tackled. In addition, in order to make better use of the traffic wind generated by the driving of vehicles, Two-hole one-way tunnel has become a common form of tunnel, and longitudinal ventilation has become the most commonly used tunnel ventilation mode. For the adjacent tunnel adjacent to the upstream and downstream two holes, the pollutants emitted from the exhaust tunnel will pollute the environment outside the tunnel. At the same time, there is "secondary pollution" caused by the channeling flow into the inlet tunnel. The existence of the channeling problem will reduce the ventilation efficiency of the tunnel with channeling flow, and the ventilation effect will not reach the expected effect. In this paper, first of all, the problem of pollutant diffusion at the entrance of the tunnel is discussed. This paper summarizes the present research situation at home and abroad, and finds out the universality of numerical simulation methods in this field. It is also found that most of the current researches are on the diffusion of holes, the channeling flow in the tunnel adjacent to a single hole and the transverse channeling in two holes. However, there is a lack of research on the problem of channeling in a tunnel adjacent to a double-hole. Based on the experimental data, the numerical simulation method is verified in this paper. The research method of simulating the problem by using FLUENT software is determined. Aiming at the tunnel adjacent to double holes under longitudinal ventilation, the evaluation scheme of channeling flow at the entrance of the tunnel is established, and from the point of view of the attached jet, Based on the analysis of the diffusive characteristics of pollutants discharged from the tunnel entrance, this paper first simulates the influence of the main factors, such as ventilation velocity, tunnel spacing and environmental wind, on the channeling flow of the tunnel under the premise of equal ventilation wind speed in the four sections of the tunnel, and draws a conclusion. When there is no influence of ambient wind, the channeling flow of the tunnel is independent of the wind speed of ventilation, and it is only related to the distance between tunnels, and when there is ambient wind, The influence of single exhaust wind speed and inlet wind speed on the channeling flow is simulated, as well as the channeling law of the tunnel under some special working conditions. The measures to improve the channeling flow are discussed. It is pointed out that the two schemes of adding partition wall and building open hole are not suitable for the tunnel adjacent to the double hole at present. On the basis of this, the feasible scheme of setting ventilation skylight on the roof of the tunnel is put forward and its feasibility is verified.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U453.5

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