16 Feb 2022

Walter Marine and Atlantic Reefmaker Wave Attenuator: Wave Transmission Testing Results

Abstract: As part of a testing service agreement with Walter Marine and Atlantic Reefmaker, a 1:5.2 physical model of the Reefmaker Wave Attenuator was constructed and tested by the US Army Engineer Research and Development Center to evaluate its influence on wave attenuation. The tested prototype wave periods ranged from 2.5 to 8 sec with prototype wave heights between 1 ft and 6.5 ft. The Reefmaker Wave Attenuator included orthogonal and square designs and was tested under a variety of configurations including a suspended configuration, a bed-mounted configuration, and a rotated configuration. Testing demonstrated that depending on configurations and wavelength, the wave transmission coefficients ranged from 0.29 to 0.70. The most improvement, however, was demonstrated when testing the square unit designs with transmission coefficients, kt, below 0.51. The smallest kt of 0.29 occurred during square unit testing, which consisted of eight bed-mounted, square Ecosystem disks plus a base unit (24.05 in. freeboard) and with a wave period of 3.0 sec and height of 0.84 ft. Of all 134 tests performed, including the suspended case, the average transmission through the structure was 58%.

29 Jun 2021

Rough River Outlet Works Physical Model Study

Abstract: The US Army Corps of Engineers, Louisville District, requested the support and assistance of the US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory (CHL), in the evaluation of the hydraulic performance of the replacement Outlet Works for Rough River Dam. To support the design effort, CHL constructed a 1:25.85 scale physical model. The proposed features of the model in the domain are the curved approach channel, intake structure, transition, curved conduit, stilling basin, concrete apron, and retreat channel. Tests performed to evaluate the hydraulic performance illuminated a few design concerns. To address these issues, several key design changes were made. These included the retreat channel slope, end sill design, and transition design.