蝶形防风网尾流区流场特性的数值模拟

发布时间：2018-10-14 10:42

【摘要】：防风网抑尘工程技术是治理大型露天料堆场二次扬尘的有效措施,其主要是由具有一定开孔率的金属网板或者编织、粘接、挤压成型的非金属网片,悬挂防风网片并起支撑作用的钢构架,地面混凝土基础组成,该技术的核心部件为防风网,而防风网尾流区的流场特性直接影响着防风网的抑尘效果。本文以当前防风网抑尘工程建设常用的蝶形防风网为研究对象,采用Fluent软件为模拟工具,进行开孔率和底部间隙对蝶形网尾流区内流场特性影响的数值模拟,并且通过与实验数据的对比来验证本文数值模型的合理性与正确性。其次,在数值模型验证正确性的基础上,开展开孔率、开孔直径、开孔形式、孔的分布情况及底部间隙对蝶形防风网尾流区内流场特性影响的数值模拟。得出了如下的结论： (1)通过模拟结果与实验数据的对比验证了本文所建立的数值模型是正确的,可以作为进行蝶形防风网相关内容研究的有效手段； (2)针对圆孔直径为6mm的蝶形防风网,开孔率Φ=0.301时庇护效果最好,减风率为65.33%； (3)针对开孔率Φ=0.301的蝶形防风网,圆孔直径D=9mm时庇护效果最好,减风率为69.274%； (4)针对开孔率Φ=0.301且开孔截面积相同的蝶形防风网,圆形开孔庇护效果最好,减风率为69.274%； (5)开孔率Φ=0.301,圆孔直径为D=6mm的蝶形防风网,以中间平板为基准将网板分为上下对称的两部分,上部Φ=0.25下部Φ=0.35时庇护效果最好,减风率为71.35%；均匀布孔时减风率为69.27%,两者差距非常小,但考虑到现实加工的难易程度和加工成本,均匀布孔的蝶形防风网应为工程首选； (6)开孔率Φ=0.273,圆孔直径D=6mm且均匀分布的蝶形网,底部间隙在0-0.025H时蝶形防风网的庇护效果最好,减风率都在60%以上。
[Abstract]:The anti-dust engineering technology of windproof net is an effective measure to control the secondary hoisting dust in large open-air storage yard. It is mainly made up of metal mesh plate with a certain opening rate or non-metal mesh that is woven, bonded and extruded. The main component of this technology is windproof net, which is composed of steel frame and ground concrete foundation. The characteristics of flow field in wake zone of windproof net have direct influence on the dust suppression effect of windproof net. In this paper, using the Fluent software as the simulation tool, the numerical simulation of the influence of the opening rate and the bottom clearance on the flow field characteristics in the wake zone of the butterfly mesh is carried out, which is commonly used in the construction of the current wind screen dust suppression engineering as the object of study, and the Fluent software is used as the simulation tool. The rationality and correctness of the numerical model are verified by comparing with the experimental data. Secondly, on the basis of the correctness of the numerical model, numerical simulation is carried out on the influence of the opening rate, the diameter of the hole, the form of the hole, the distribution of the hole and the bottom clearance on the characteristics of the flow field in the wake zone of the butterfly windbreakers. The conclusions are as follows: (1) by comparing the simulation results with the experimental data, the numerical model established in this paper is proved to be correct and can be used as an effective means to study the relevant contents of the butterfly windbreak network; (2) for butterfly wind-proof mesh with round hole diameter of 6mm, the opening rate 桅 = 0.301 is the best, and the wind reducing rate is 65.33.The (3) for the butterfly windproof net with opening rate 桅 = 0.301, the sheltering effect is the best when the diameter of circular hole is D=9mm, and the wind reducing rate is 69.274; (4) for the butterfly wind-proof net with opening ratio 桅 = 0.301 and the same cross section area, the circular aperture has the best shelter effect, and the wind reducing rate is 69.274.The (5) the butterfly wind mesh with opening rate 桅 = 0.301 and the diameter of the circular hole D=6mm, is the best, and the diameter of the circular hole is D=6mm, the diameter of the circular hole is D=6mm. On the basis of the intermediate plate, the mesh plate is divided into two parts: the upper section 桅 = 0.25, the lower 桅 = 0.35, the sheltering effect is the best, the wind reducing rate is 71.35, and the air reducing rate is 69.27 when the holes are evenly arranged, the difference between them is very small. However, considering the difficulty and cost of machining in reality, the butterfly windproof mesh with uniform hole placement should be the first choice for engineering; (6) the opening ratio 桅 = 0.273, the diameter of circular hole D=6mm, and the evenly distributed butterfly mesh, When the bottom gap is 0-0.025H, the sheltering effect of butterfly windproof net is the best, and the wind reduction rate is above 60%.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：X964

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