Irrigation Sciences and Engineering

Irrigation Sciences and Engineering

the Impact of Long Tree Canopy on Changes in the Force of Solitary Breaking and Non-breaking Coastal waves

Document Type : Research Paper

Authors
parisa Azinfar 1
Manoochehr Fathi Moghadam 2
Javad Ahadiyan 3
1 Ph.D. of Hydraulic Structures, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Iran.
2 Professor of Hydraulic, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Iran.
3 Professor of Hydraulic Structures, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Iran; and Center of Excellence of the Irrigation and Drainage Networks Improvement and Maintenance, Ahvaz 61357-43311, Iran.
10.22055/jise.2021.32311.1904
Abstract
Coastal vegetation belts, depending on their capacity, can play a significant role in reducing coastal hazards or restoring the coast by attenuating waves, trapping and accumulating sediments, and rehabilitating the soil. Therefore, the role of coastal vegetation in modifying coastal characteristics and reducing the severity of damage through wave damping is of great importance. This study aims to investigate the effects of density, width of tall tree vegetation, and wave propagation velocity, as well as to determine the significance of these factors on the changes in the destructive force of breaking and non-breaking waves. To model tree trunks, non-flexible wooden stems with a diameter of 1 cm and a height of 30 cm were used. These cylindrical stems were installed on the beach section of the flume, and the force exerted on the obstacles by the waves was recorded using a direct measurement method with an electronic load cell installed beneath the movable section of the flume. The experiments were conducted with a fixed parallel arrangement, varying spacings of 5×5 and 10×10 cm, different vegetation widths of 10, 20, and 40 cm, and a constant bed slope of zero. Considering 40 different wave heights and control tests without vegetation, a total of 280 different conditions were examined. According to the experimental data, for a fixed vegetation width, the highest increase in force absorption occurred at a density of 5×5, which was 1.81 times greater than that at a density of 10×10. Finally, based on the experimental data, an empirical relationship between the drag coefficient and the Reynolds number was proposed.
Keywords
Breaking and Non-Breaking Waves
Coastal Protections
Wave Damping
Destructive Force of Waves
Subjects

 

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Irrigation Sciences and Engineering
Volume 49, Issue 1
Spring 2026
Pages 1-21

  • Receive Date 25 April 2020
  • Revise Date 20 December 2020
  • Accept Date 03 January 2021
  • Publish Date 05 May 2026