动床模型泥沙运动相似问题

Similarity of Sediment Movement of Movable-bed Model

根据阻力相似要求,导出泥沙运动相似比尺,如床沙起动粒径比尺,悬沙粒径比尺,推移质输沙率比尺和悬移质含沙量比尺等。使得用起动流速和起动拖曳力来演绎的上述比尺异途同归,得到统一。指出阻力相似是泥沙运动相似的必要条件,动床模型因加减糙困难,阻力相似与弗氏数相似一般难以同时满足,弗氏数相似适当偏离是不可避免的。

Based on the requirement of resistance similarity,similarity scales of sediment movement were derived and unified,such as those of bed material size,suspended material size,rate of transport of bed load and concentration of suspended load.It's shown that resistance similarity is the requisition of sediment movement similarity.And it's difficult to reach similarities of resistance and Froude number at the same time,as the hardness of roughening on the movable bed.Therefore,slight deviation of Froude number similarity is proper.