synergistic Effects of Bed Macroroughness and Positive Inclination on the Morpho dynamics and Energy Dissipation of Hydraulic JumpsAmin

10.22034/cpj.2026.585612.1448

Articles in Press, Accepted Manuscript
Available Online from 10 June 2026

Document Type : Review Article

Authors

1 civil department , isalmic azad university , sepidan , iran

2 MSC of Civil engineering , Sep. C., Islamic Azad University, Sep, Iran

Abstract
Hydraulic jumps are a critical phenomenon in fluid mechanics, widely utilized in hydraulic engineering structures such as energy dissipation basins. These structures — including relaxation ponds located downstream of spillways, steep channels, and control valves — rely on the energy-dissipating characteristics of hydraulic jumps to manage and reduce the destructive force of fast-moving water before it continues downstream. To better understand the behavior and effectiveness of hydraulic jumps under various conditions, a series of controlled laboratory experiments were carried out. A total of 60 experimental runs were performed using a rectangular flume measuring 35 centimeters in width. The inlet Froude numbers tested ranged from 4 to 12, covering a broad spectrum of supercritical flow conditions. Throughout the study, two distinct types of bed roughness were examined — sharp corner roughness and diamond (rhombus) shaped roughness elements — both installed on the channel floor. In addition to roughness type, the longitudinal slope of the flume bed was systematically varied between 0% and 0.3% to assess its influence on jump characteristics. During each experimental run, several key hydraulic parameters were precisely recorded, including discharge rate, sequent depth ratio, jump length, water surface profile, flow depth upstream and downstream of the jump, and water head measurements at the weir crest. The findings of the study revealed meaningful differences in hydraulic jump behavior depending on the roughness configuration. Specifically, the presence of sharp corner roughness elements led to a notable reduction in the ratio of jump length to sequent depth — approximately 35.5% lower compared to a smooth bed. Furthermore, the sequent depth ratio increased by an average of 6.5% for sharp corner roughness. In contrast, diamond-shaped roughness showed a more modest influence, producing only a 1.2% average reduction in the jump length-to-sequent depth ratio

Keywords

Subjects
  • Receive Date 08 June 2026
  • Accept Date 10 June 2026
  • First Publish Date 10 June 2026
  • Publish Date 10 June 2026