潮汐河工模型三角块梅花形加糙试验研究及其应用 （徐华）
【作者】徐华 【导师】夏益民; 夏云峰
【作者基本信息】南京水利科学研究院，水力学及河流动力学，2006年，硕士
【中文摘要】 变态河工模型中，原型和模型之间要求满足阻力相似。根据变态模型阻力相似要求，变态模型一般需要人工加糙。变态潮汐河工模型中，由于潮汐河道中涨落潮糙率的差异，要求模型加糙糙率也不同。以往加糙体如石子、十字板和条杆形物体等均不能满足这个要求，而三角块加糙体可以满足这一要求。 论文对用于河工模型的常见人工加糙方法进行了总结，列出了各种加糙方法的计算过程；分析了天然河道阻力的影响因素，列出了计算天然河道糙率的三个常用方法。本次水槽试验三角块加糙体平面形状一定，论文从理论上分析了三角块梅花形加糙糙率的主要影响因素：三角块厚度Δ、布置横距L、布置纵向p、水深h和粘贴方向(假定顶点迎流为正向，底边迎流为反向)。通过水槽均匀流试验，计算得出了不同粘贴方向、不同三角块厚度、不同布置间距和不同水深条件下若干种粘贴方案加糙糙率大小。 在横距L等于纵距P的情况下，根据试验成果，论文分别拟合了三角块正向、反向梅花形粘贴的糙率计算公式，并将公式计算值与试验实测计算值进行了对比分析，得出两者偏差在10％以内，公式具有较好的精度。 另外，论文也对横距L不等于纵距P(L、P范围在10cm～20cm内)的粘贴方式进行了试验研...更多究，并用横距L等于纵距P的糙率计算公式分别计算了加糙糙率值，其中间距用算术平均值(LP)1／2代入计算。计算结果表明：该种情况下，正反向粘贴糙率计算值与实测值偏差均在10％以内。 最后，将三角块梅花形加糙研究成果应用于长江河口段大模型。模型潮位和流速验证试验表明：模型潮位、流速与天然基本一致，模型较好地复演了天然河道水流运动规律，三角块梅花形加糙研究成果可靠。 还原
【英文摘要】 Resistance similarity between prototype and model must be satisfied in the distorted river model. According to this need, the distorted model generally needs artifical roughness. Because roughness during the time of rising tide is different from that during the time of ebbing tide in the tidal river, roughness is also variable in different water direction. Previously roughness blocks such as gravels, cross plates and bar objects can not meet this need, however, triangle blocks can do this just right.Research achievements related to model roughness were presented first, and calculating processes of all kinds of roughness methods were listed. This paper also analyzed influencing factors on resistance and summarized three common methods for computing roughness of the natural river. The plane shape of triangle block was given in this test, then theoretically the main influencing factors on roughness of quincunx-pasted triangle blocks were as following: thickness (Δ), lateral distance (L), ...更多portrait distance (P), water depth (h) and pasted direction (forward: vertex meeting current; backward: bottom meeting current).Based on uniform flow experiments in the flume, roughness of all kinds of combined influencing factors was obtained. When L was equal to P, based on the experiment data, semi-empirical and semi-theoretical forward formula and backward formula were deduced for computing roughness, and comparing computing values with experiment values, error range is within 10%. It indicates that the formulas have good accuracy. When L was not equal to P, the paper also compared computing values with experiment values, and error range is within 10%.The research of this paper on Quincunx-pasted triangle blocks was applied to the model of the estuary reach of the Yangtze River from Jiangyin to Wusongkou. The verification test of tidal level and velocity indicated that tidal level and velocity between prototype and model were basically identical, and the model preferably simulated water movement. Above all, the research of quincunx-pasted triangle blocks is reliable. 还原
【中文关键词】 潮汐河工模型; 阻力相似; 三角块梅花形加糙; 正反向粘贴
【英文关键词】 tidal river model; resistance similarity; Quincunx-pasted triangle blocks roughness; forward or backward pasted
