Laboratory experiments of surf zone dynamics under on- and offshore wind conditions

摘要

This paper presents detailed laboratory experiments investigating the effect onshore and offshore wind conditions have on nearshore wave dynamics, including extreme winds. The experiments were performed using monochromatic waves and a linearly sloping bed. The results show that offshore wind conditions delay wave breaking and promote steep breakers, while onshore wind conditions extend the surf zone and flatten the waves. Firstly, linear and cnoidal wave models were used in standard formulations to predict the cross-shore wave evolution under no-wind conditions. Secondly, wind effect was added to account for wind-induced modifications of breaker height and energy balance. Despite experimental limitations, the overall satisfactory agreement between theory and observations suggests that such an approach can be used to describe the wind effect in wave nearshore models.