Forced hydraulic jump on non-protruding rough beds

Abstract

Baffle blocks and sills are commonly used to stabilize the location of a hydraulic jump and shorten its length. However, corrugations or prismatic roughness elements may be effective alternatives to them. In the present study, experiments were performed to determine the effects of corrugations and prismatic roughness elements on fundamental characteristics of jump such as length, tailwater depth, and energy dissipation capacity. Corrugations were placed to cover the entire length of the basin. Prismatic roughness elements were placed in two different arrangements as strip and staggered. The results showed that the length of jump was reduced about 35% by corrugations, 40% by strip roughness, and 35%–55% by staggered roughness. The tailwater depth reduction was 20% for corrugations, 5%–13% for strip roughness, and 7%–15% for the staggered roughness compared to classical jump. The roughness elements induce 3%–10% more energy dissipation than that of classical jump.