7/17/2019 Ewans

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If kpd>0.5 none of the commonly applied design wave solutions provide a good descriptionof the kinematics. This includes a very high-order regular or steady wave solution based onan equivalent !"T#$ a linear random wave model based on a focused %ew&ave event withspeci'ed !()* or +()* and including &heeler stretching$ and a second-order correction tothe latter based upon the iterative application of the solution proposed by ,harma ean/1/#. The preferred approach entirely depends upon what aspect of the velocity 'eld is

most important. If it is the near-bed velocities" a high-order regular wave theory is probablypreferable in that it typically provides the smallest over-prediction. If" however" the near-surface kinematics are more important" a second-order model should be applied" but withgreat care e2ercised in terms of the truncation of the wave spectrum