This study analyzed the characteristics of scour holes located downstream of cross vanes. A numerical model was developed and used to simulate the flows and bed changes of cross vanes in straight channels. The morphologies and sizes of scour holes located downstream of cross vanes were examined. The results revealed that the chambers of the investigated cross vanes were a key factor affecting the morphologies of the investigated scour holes,which were classified on the basis of the ratios of the cross-vane arc length (L), scour length (l m), and channel width(B). When L/B decreased from 2.3 to 1.4, the position of the maximum scour depth gradually shifted from the inside to the outside of the cross vanes, eventually resulting in scour morphology that resembled the morphology of a conventional cross vane; in this scenario l m/B also decreased from 2.5 to 1.6.
Key Words: Cross vane, Numerical simulation, Scour holes