Author(s): Chen Jie; Jiang Changbo; You Tao; Liu Huying
Linked Author(s):
Keywords: Submerged breakwater; Wave energy spectrum; Turbulence intensity; Power spectrum of turbulent flow velocity
Abstract: Submerged breakwaters have become increasingly popular due to their multiple functions, which are to protect shoreline or harbor and to prevent beach erosion in the coastal zones. In this paper trapezoidal submerged breakwater in the coastal zones was modeled using a wave flume. Based on the experimental data collected, characteristics of changing wave profile, energy spectrum, statistic and spectrum parameters of regular waves and flow were calculated and analyzed, including 3D instantaneous velocities, turbulence intensity, Reynolds stress, turbulent kinetic and power spectrum of turbulent flow velocity. The result shows that the wave profile becomes strongly asymmetry and wave energy in lower harmonic is transferred into higher harmonic. At the back of submerged breakwater the wave energy rapidly decreases. The fluid motion near the bed is turbulent and the pulsating velocity shows that the turbulence intensity near the bed is larger than the turbulence intensity far away from the bed. The higher harmonics generate and intensify near the bottom or when the water depth decreases. Especially on the top of submerged breakwater, the turbulence intensity, Reynolds stress and turbulent kinetic energy become extraordinarily strong.
Year: 2009