St. Grilli et al., BREAKING CRITERION AND CHARACTERISTICS FOR SOLITARY WAVES ON SLOPES, Journal of waterway, port, coastal, and ocean engineering, 123(3), 1997, pp. 102-112
Shoaling and breaking of solitary waves is computed on slopes from 1:1
00 to 1:8 using an experimentally validated fully nonlinear wave model
based on potential how equations. Characteristics of waves are comput
ed at and beyond the breaking point, and geometric self-similarities o
f breakers are discussed as a function of wave height and bottom slope
. No wave breaks for slopes steeper than 12 degrees. A breaking criter
ion is derived for milder slopes, based on values of a nondimensional
slope parameter S-o. This criterion predicts both whether waves will b
reak or not and which type of breaking will occur (spilling, plunging,
or surging). Empirical expressions for the breaking index and for the
depth and celerity at breaking are derived based on computations. All
results agree well with laboratory experiments. The nonlinear shallow
water equations fail to predict these results with sufficient accurac
y at the breaking point. Prebreaking shoaling rates follow a more comp
lex path than previously realized. Postbreaking behaviors exhibit a ra
pid (nondissipative) decay, also observed in experiments, associated w
ith a transfer of potential energy into kinetic energy. Wave celerity
decreases in this zone of rapid decay.