137. Energy Loss at a Drop Structure with a Step at the Base

The flow over a drop structure placed in a rectangular channel was investigated through an experimental program. It was noted that the downstream depth of flow was crucial to the formulation of the problem. Two procedures were developed for the estimation of the downstream depth. The first procedure was physically based with an empirical component for the estimation of the depth of the pool formed at the base of the drop. The second was a purely empirical procedure, which resulted in an equation for the direct estimation of the downstream depth. The parameters of the equation were determined by least-squares techniques. Both procedures resulted in reasonably accurate estimates of the downstream depth. The energy loss at the drop was then calculated and compared with the results of previous studies. The investigations were repeated with a single step placed at the base of the drop. It was observed that the step significantly increased the energy loss at the drop.