Analysis of scour and siltation in storm conduit based on flush index
Although the single-factor indicators such as flow velocity,Reynolds number,and depth ratio are related to the flush and silt volume of the storm conduit,the single-factor indicators are not enough to comprehensively judge the flush and siltation of the storm conduit.In this study,the concept of flush index is proposed on the basis of pick-up velocity and braking velocity.Com-bined with the flush and silt volume simulation under different working conditions of continuous and non-constant flow,gray relational analysis between flush volume and the four factors,which are flow velocity,Reynolds number,depth ratio and flush index,is made.The correlation degree is as follows:flush index>Reynolds number>depth ratio>flow velocity.According to the re-sults of the constant flow model experiments under different working conditions,the correlation degree is as follows:flush index>>flow velocity>Reynolds number>depth ratio.It can be considered that under the condition of continuous and discontinuous flow,there is a significant strong correlation between the flush volume and the flush index,and the flush index can replace the specific flush volume calculation to achieve a reasonable judgment of the degree and trend of the flushing.