Breaker Types and Wave Reflection Coefficient: Laboratory Relationships


  • Tsuguo Sunamura
  • Sei-Ichi Okazaki


Surf similarity parameter, breaking waves, impermeable plane beaches


Re-analyses of the existing reflection data obtained from regular wave experiments on a smooth, impermeable, uniformly inclined beach lead to the following empirical relation:

Kr = 0.84[1 - exp(- 12.8 tan β] tan h (0.11ξ02.4)

where Kr is the wave reflection coefficient, β is the beach slope angle, and ξ0 is the surf similarity parameter. The breaker type is linked with this equation through the value of ξ0. The reflection coefficient increases as the breaker type changes from spilling to collapsing through plunging, and it becomes constant for surging breakers. It is found that reflection coefficients of collapsing and surging breakers are strongly affected by the beach slope.