Wave Decaying Due to Breaking

Wave Characteristics in the Surf Zone

“…2 which shows the relative change in wave height H/H versus the distance from the breaking point measured in units of h. . Horikawa & Kuo (1966) and by Nakamura et al (1966) on a similar slope (1 in 30 against ours 1 in 34) though the above mentioned conjecture implies that the effect of the slope is insignificant. It is worth noticing that the wide range of wave parameters in Fig.…”

Wave height variation across beaches of arbitrary profile

“…Specifically, wave height and its spatial gradients generate or have direct impact on sediment mobilization and suspension, littoral currents in both the alongshore and onshore/offshore directions, waveinduced set-down/set-up in the mean water level, and forces on coastal structures. While the "0.78" criterion (ratio of breaker height to water depth equals 0.78) appears to provide a reasonable prediction of incipient breaking on mildly sloping beaches, data show that this criterion does not hold farther into the surf zone [Horikawa and Kuo, 1966;Nakamura et al, 1966;Street and Camfield, 1966;Divoky et al, 1970]. In fact, these data show that such a similarity model is especially inappropriate on mild slopes, just where many coastal scientists assume that it is most valid.…”

Breaking Wave Setup and Decay on Gentle Slopes

“…The transformation of a breaking wave over a slope is a problem of obvious concern in the design and planning of coastal facilities A number of investigators have considered this topic, including Freeman and LeMe'haute' (1964), Horikawa and Kuo (1966), LeMehaute* (1962), Divoky, LeMehaute", and Lin (1970), Nakamura, Shiraishi, and Sasaki (1966), and Street and Camfield (1966) The present contribution considers an essential aspect neglected m previous studies, the phenomenon of "wave set-up " Set-up, while negligible seaward of the breaking point, becomes dominant with respect to still-water depth as the shore is approached It is apparent, then that any analysis of breaking wave height transformation should account for the set-up Experimental investigations of set-up have been made by Saville (1961) and by Bowen, Inman, and Simmons (1968) with the result that the maximum elevation may be a significant fraction (~ 50%) of the breaking wave height Additionally, measurements obtained during the Mono Lake explosion-wave tests indicated a set-up value equalling the maximum height of the superposed dispersive wave train (Van Dorn, et al, 1968) Hwang (1970 also investigated dispersive wave trains and found a fluctuating set-up of roughly half the peak wave height Wave set-up has been investigated extensively in a series of papers by 61,62,64) from an analytical approach The difficulty m applying their results to the Tetra Tech, Inc , Pasadena, California surf zone, arises from the problem of finding an adequate description of the waves after breaking Bowen, Inman, and Simmons (1968) assumed that the wave height remains a constant fraction of mean water depth after breaking and found, from a momentum balance, a linear set-up variation…”