Directional spread parameter at intermediate water depth

The characteristics of directional spread parameters at intermediate water depth are investigated based on a cosine power '2s' directional spreading m odel. This is based on wave measurements carried out using a Datawell direc tional waverider buoy in 23 m water depth. An empirical equation for the fr equency dependent directional spreading parameter is presented. Directional spreading function estimated based on the Maximum Entropy Method is compar ed with those obtained using a cosine power '2s' parameter model. A set of empirical equations relating the directional spreading parameter correspond ing to the peak of wave spectrum to other wave parameters like significant wave height and period are obtained. It shows that the wave directional spr eading at peak wave frequency can be related to the non-linearity parameter , which allows estimation of directional spreading without reference to win d information. (C) 2000 Elsevier Science Ltd. All rights reserved.