潮汐河工模型三角块梅花形加糙试验研究及其应用

Research on roughness of quincunx-pasted triangle blocks and its application in tidal river model

通过水槽均匀流试验,研究了三角块不同粘贴方向、厚度、布置间距和水深条件下若干种粘贴方案加糙糙率.根据试验结果,推导了三角块正向、反向梅花形粘贴糙率计算式,计算值与实测值偏差在10%以内.将三角块梅花形加糙研究成果应用于长江河口段模型,模型潮位和流速均与实测值基本一致,模型能较好地复演天然水流运动规律.

Previously roughness blocks such as gravels, cross plates and bar objects could not meet the need of roughness, however, triangle blocks can do it ideally. The main influencing factors on roughness of quincunxpasted triangle blocks are as following： thickness, lateral distance, portrait distance, water depth and pasted direction （forward： vertex meeting current; backward： bottom meeting current）. Based on uniform water experiments in the flume, roughness of all kinds of pasted schemes is obtained. Based on the experiment result, when L is equal to P, semi-empirical and semi-theoretical forward formula and backward formula are deduced for computing roughness, and comparing computing values with experiment values, error range is within 10%. It indicates that the formulas have good accuracy. The research in this paper on Quincunx-pasted triangle blocks is applied to the model of the estuary reach of the Yangtze River from Jiangyin to Wusongkou. The verification test of tidal level and velocity indicates that tidal level and velocity in both prototype and model are basically identical, and the model can simulate water flow better.