{'fraction_non_alphanumeric': 0.020646669263731984, 'fraction_numerical': 0.006622516556291391, 'mean_word_length': 5.014051522248243, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Wind wave evolution in fin

This paper presents recent research aimed at developing a detailed predictive capability for wind generated ocean waves in shallow coastal waters. The detailed evolution of the directional spectrum, and measurements of the source terms responsible for this evolution are presented. Introduction Wind generated ocean waves are important for a number of reasons. From an engineering viewpoint, they represent the major loading on coastal and offshore structures. From the environmental context, they have a governing role in the stability of coastlines and the flooding of near-coastal regions during storm condition. Wind generated waves also largely govern the aerodynamic roughness of the ocean surface and hence play a major role in determining the fluxes of heat, energy, momentum and possibly carbon dioxide across the ocean surface. Thus accurate prediction of ocean wave conditions may also be a key variable in predicting long-term climate. The study of gravity waves has been a fertile area of fluid mechanics for many centuries. Our abilities to predict the generation and evolution of ocean waves on a global or regional scale only started to develop in the 1950s (Gelci et al, 1956 [4]). The sophistication of such models has increased as both computing power grew and our understanding of the, often complex, nonlinear processes governing wind-wave evolution increased. This development has culminated in the introduction of 3 Generation spectral models, capable of predicting wave fields on either a global of regional scale (WAMDI, 1988 [10]). Despite the significant developments which have occurred in this area, the resulting models have largely been confined to areas of deep water, where the influences of finite depth can be ignored. Although deep-water regions include the vast majority of the world’s oceans, it is in the relatively small shallow coastal regions where the bulk of human activity is concentrated. Until recently, both the form of wind generated waves in shallow coastal regions and the mechanisms responsible for their evolution have been poorly understood. This paper describes a number of integrated field research projects aimed at addressing this lack of knowledge. Governing Equations For the simplifying case of a constant water depth, the evolution of the directional wave spectrum can be described by the energy balance equation F F Stot t ∂ + ⋅∇ = ∂ Cg (1) where F is the directional wave spectrum, t is time, Cg is the group velocity and Stot is a source term which represents all proc of th