基于起动相似选沙的模型沙波相似性的初步试验研究  

Preliminary Study on Sand Wave Similarity Constrained by the Similarity Criterion of Incipient Motion

作　　者：陈立[1] 徐敏[1] 黄杰[1] 何俊[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《四川大学学报（工程科学版）》2016年第3期35-40,共6页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(11472199)

摘　　要：沙波普遍存在于天然河道中,动床模型中沙波运动的相似性是水流运动、泥沙输移及河床冲淤相似的基础。针对动床模型中沙波相似性问题,采用水槽试验的方法,设计满足几何、水流运动、起动相似的沙波试验,分析了沙波波高、沙波组成的相似性。结果表明,对于几何正态模型,在模型沙与原型沙重率相同的情况下,沙波波高基本满足几何相似,平均偏差约在9.2%左右;沙波波高随水流强度的变化规律是相似的,U/U_c=2.0时开始出现沙波,沙波随着水流强度的增大而逐渐增大,当U/U_c接近2.6时,沙波达到最大波高;沙波相同部位的颗粒组成也是相似的。即原型沙与模型沙在重率、形状相同的条件下,考虑起动相似的正态模型沙波是相似的。For movable bed model, sand wave movement similarity is the basis of the similarity of flow, sediment transportation and river bed evolution. Based on flume experiment, which meets the similarity of geometric,flow and incipient motion,similarities of sand wave height and its composition were analyzed. The results showed that for the normal model with the same weight ration of prototype sand and model sand,sand wave height is largely in line with geometric similarity and the average deviation is only about 9.2%. Sand wave height varies with flow intensity. Sand wave emerges when U/Uc is 2.0 and extends with the increase of flow intensity. Sand waves reach their maximum height when U/Uo is 2.6. Finally, particle composition in the same part of different sand waves is similar. In conclusion, with the same density and shape, natural sand wave and model sand wave correspond to the similarity law in a normal mold when incipient motion is taken into consideration.

关 键 词：沙波相似性 波高 水流强度 颗粒组成 

分 类 号：TV142[水利工程—水力学及河流动力学]