【摘要】 准确预报群汊河道中污染物扩散范围与混合过程，可为工业和市政排放工程的设计、取水口保护区范围的确定、水资源保护等提供科学依据。选取存在3～5个分汊岛的群汊河道，开展不同上游流量和排污位置工况的3种典型群汊河道污染物输移物理模型试验，在群汊段各汊道布置污染物浓度测量断面。选取代表断面并计算污染物混合偏差程度值，分析不同上游流量和排污位置条件下，污染物浓度分布在群汊段沿程变化情况。计算群汊河道出口汇流断面的污染物混合偏差程度值，分析上游流量和排污位置对出口汇流断面浓度分布的影响。结果表明，在相同流量、同一排污位置条件下，断面混合偏差程度值沿程减小；在同一排污位置条件下，随着分汊岛数量的增多，群汊段出口汇流断面混合偏差程度值越小。更多还原

【Abstract】 The accurate prediction of pollutant diffusion range and mixing process in the multi-anabranch river can provide scientific basis for the design of industrial and municipal discharge projects, the determination of the scope of water intake protection area, and the protection of water resources. The physical model test of pollutant transport in three typical multi-anabranch rivers with 3～5 braid bars is carried out under different upstream flow and sewage discharge location conditions, and pollutant concentration measurement sections are arranged in each branch of the multi-anabranch reach. Representative sections are selected and the degree of pollutant mixing deviation is calculated, and the variation of pollutant concentration distribution along the multi-anabranch reach is analyzed under different upstream flow and blowdown position conditions. The pollutant mixing deviation value of the outlet confluence section of the multi-anabranch river is calculated, and the influence of the upstream flow and blowdown position on the concentration distribution of the outlet confluence section is analyzed. The results show that under the condition of the same flow rate and the same blowdown position, the degree of cross section mixing deviation decreases along the way. With the increase of the number of braid bars, the mixing deviation degree of the outlet confluence section of the multi-anabranch reach is smaller under the condition of the same blowdown position.更多还原