An Experimental Analysis of the Impact of the Transverse Distance of Cubic Obstacles on the Hydraulic Characteristics of Transverse Waves in Staggered Arrangements

Document Type : Research Article

Authors

Department of Water Structures, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran

Abstract

Transverse waves are formed by obstacles such as vegetation, bridge piers, and docks in the flow path. the present study investigated the effect of the transversal distance of cubic obstacles on the hydraulic characterization of transverse waves with four-wave modes in resonance. The obstacles were arranged staggered at two transversal distances and a constant longitudinal distance. All experiments were performed in a flume with a length of 16 m, a width of 1.25 m, and a height of 0.6 m. The flow discharge was varied between 30 and 38 lit/s in the experiments. The results showed that the flow regime was turbulent and sub-critical in experiments. In resonance, the Obstacle Reynolds Number and Froude Number were within the range of 2319<Re<5627 and 0.055<Fr<0.210 respectively. In resonance, the relative amplitude of the wave increases by increasing the transversal distance of obstacles (decreasing the density of obstacles), and the highest relative amplitude of 33% was obtained for T/D=9.6, wave mode IV, and Q=30 lit/s. With the increase in discharge, the relative amplitude of the wave in each transversal distance and all four wave modes decreased.

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References

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Amirkabir Journal of Civil Engineering
Volume 56, Issue 5
2024
Pages 551-568

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