• Title/Summary/Keyword: transmitted waves via a porous wave breaker

Search Result 1, Processing Time 0.015 seconds

The Effect of Skewness of Nonlinear Waves on the Transmission Rate through a Porous Wave Breaker (파형의 왜도가 투과성 방파제 투과율에 미치는 영향)

  • Cho, Yong Jun;Kang, Yoon Koo
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.29 no.6
    • /
    • pp.369-381
    • /
    • 2017
  • It has been presumed that highly nonlinear skewed waves frequently observed in a surf zone could significantly influence the transmission behaviour via a porous wave breaker due to its larger inertia force than its nonlinear counterparts of zero skewness [Cnoidal waves]. In this study, in order to confirm this perception, a numerical simulation has been implemented for 6 waves the skewness of that range from 1.02 to 1.032. A numerical simulation are based on the Tool Box called as the ihFoam that has its roots on the OpenFoam. Skewed waves are guided by the shoal of 1:30 slope, and the flow in the porous media are analyzed by adding the additional damping term into the RANS (Reynolds Averaged Navier-Stokes equation). Numerical results show that the highly nonlinear skewed waves are of higher transmitted ratio than its counterparts due to its stronger inertia force. In this study, in order to see whether or not the damping at the porous structure has an effect on the wave celerity, we also derived the dispersive relationships of Nonlinear Shallow Water Eq. [NSW] with damping at the porous structure being accounted. The newly derived dispersive relationships shows that the phase lag between the damping friction and the free surface elevation due to waves significantly influence the wave celerity.