Abstract:In order to investigate the improvement effect of the arrangement parameters of oblique sillsat the bend flow in the spillway, indoor hydraulic model experiments were carried out. Improvement effect of water flow in the bend of each scheme were analyzed and compared. The results show that the arrangement of oblique sills can improve the bend flow condition, and improve the evenness of water surface meanwhile reduce the water surface difference in cross-sections. Furthermore, in the condition that the number of permeable oblique sills is higher withlarger sillheight and lower discharge, the water level at the convex bank is higher than that at the concave bank where maximum water surface difference appear. The regression analysis method was used to establish the prediction model of the improvement effect of the water surface in the bend considering the parameters of the permeable oblique sill, including the sill height, sill number and permeability rate, which can be used as a reference for engineering design.