含沙高速水流掺气特性和掺气抗磨作用

Characteristics of Aeration in High velocity Sediment Flow and the Effect of That on Abrasion Resistance of Boundary Material

n the basis of model tests and prototype observation,83 sets of aeration data are analyzed. Then, a series of formulae for estimating the air entraining capacity of the flow over the ramp and the protected length below the ramp are proposed,Because Reynolds number and sediment concentration as well as Froude number and geometry parameters are all taken int consideration,these fourmulae may be used for hydraulic design of outlet structures of any scale,The experimental study on the effect of aeration on abrasion resistance of material in sediment flow has been done by the help of a special circulating system with high velocity,and 35 sets of data have been observed. Based on the regression analysis for these data,a formula for predicting the abrasive wear caused by sediment flow is given. It shows that the abrasion rate is related to the flow velocity , the sediment content,the strength of material and the air concentration. The thicker the air concentration,the lighter the abrasion.