Experimental Study of Energy Loss in a Stepped Spillway Equipped with Inclined Steps in the Nappe and Skimming Flow Regimes

Scrutinizing the considerable flow energy in a spillway plays a significant role in maintaining downstream dam safety, and due to this fact, the dimension of the stilling basin will be enormously reduced, and from an economical point-of-view, construction costs will dramatically reduce. This phenomenon may even result in the removal of the stilling basin. A stepped spillway is one of the best structures for this purpose. In this experimental study, steps in the stepped spillway are equipped with inclined steps with various slopes, to find out how they influence their relative energy loss. Results illustrate that using inclined steps, considerably affect both the nappe and skimming flows; however, the energy loss in nappe flows is greater than that in skimming flows. Analyzing the results of experimental tests side-by-side with the results obtained from other researchers makes clear that the method used in the current investigation is more efficient than previous ones.